Search results for: moving shock wave

Authors: Valentina Dolmova

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What consumers choose to buy and who voters select on election days are two questions that have captivated the interest of both academics and practitioners for many decades. The importance of understanding what influences the behavior of those groups and whether or not we can predict or control it fuels a steady stream of research in a range of fields. By looking only at the past 40 years, more than 70 thousand scientific papers have been published in each field – consumer behavior and political psychology, respectively. From marketing, economics, and the science of persuasion to political and cognitive psychology - we have all remained heavily engaged. The ever-evolving technology, inevitable socio-cultural shifts, global economic conditions, and much more play an important role in choice-equations regardless of context. On one hand, this makes the research efforts always relevant and needed. On the other, the relatively low number of cross-field collaborations, which seem to be picking up only in more in recent years, makes the existing findings isolated into framed bubbles. By performing systematic research across both areas of psychology and building a parallel between theories and factors of influence, however, we find that there is not only a definitive common ground between the behaviors of consumers and voters but that we are moving towards a global model of choice. This means that the lines between contexts are fading which has a direct implication on what we should focus on when predicting or navigating buyers and voters’ behavior. Internal and external factors in four main categories determine the choices we make as consumers and as voters. Together, personal, psychological, social, and cultural create a holistic framework through which all stimuli in relation to a particular product or a political party get filtered. The analogy “consumer-voter” solidifies further. Leading academics suggest that this fundamental parallel is the key to managing successfully political and consumer brands alike. However, we distinguish additional four key stimuli that relate to those factor categories (1/ opportunity costs; 2/the memory of the past; 3/recognisable figures/faces and 4/conflict) arguing that the level of expertise a person has determines the prevalence of factors or specific stimuli. Our efforts take into account global trends such as the establishment of “celebrity politics” and the image of “ethically concerned consumer brands” which bridge the gap between contexts to an even greater extent. Scientists and practitioners are pushed to accept the transformative nature of both fields in social psychology. Existing blind spots as well as the limited number of research conducted outside the American and European societies open up space for more collaborative efforts in this highly demanding and lucrative field. A mixed method of research tests three main hypotheses, the first two of which are focused on the level of irrelevance of context when comparing voting or consumer behavior – both from the factors and stimuli lenses, the third on determining whether or not the level of expertise in any field skews the weight of what prism we are more likely to choose when evaluating options.

Keywords: buyers’ behaviour, decision-making, voters’ behaviour, social psychology

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Authors: Noorh Albadi, Salha Khayyat

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People's moods and well-being are affected by their environment. The built environment impacts one's level of activity and health. In order to enhance users' physical health, sustainable design strategies have been developed for the physical environment to improve users' health. This study aimed to determine whether adult resorts in Saudi Arabia meet standards that ensure physical wellness to identify the needed requirements. It will be significant to the Ministry of Tourism, Sports, developers, and designers. Physical activity affects human health physically and mentally. In Saudi Arabia, the percentage of people who practiced sports in the Kingdom in 2019 was 20.04% - males and females older than 15. On the other hand, there is a lack of physical activity in Saudi Arabia; 90% of the Kingdom's population spends more than two hours sitting down without moving, which puts them at risk of contracting a non-communicable disease. The lack of physical activity and movement led to an increase in the rate of obesity among Saudis by 59% in 2020 and consequently could cause chronic diseases or death. The literature generally endorses that leading an active lifestyle improves physical health and affects mental health. Therefore, the United Nations has set 17 sustainable development goals (SDGs) to ensure healthy lives and promote well-being for all ages. One of SDG3's targets is reducing mortality, which can be achieved by raising physical activity. In order to support sustainable design, many rating systems and strategies have been developed, such as WELL building, Leadership in Energy and Environmental Design, (LEED), Active design strategies, and RIPA plan of work. The survey was used to gather qualitative and quantitative information. It was designed based on the Active Design and WELL building theories targeting beach resorts visitors, professional and beginner athletes, and non-athletics to ask them about the beach resorts they visited in the Kingdom and whether they met the criteria of sports resorts and healthy and active design theories, in addition to gathering information about the preferences of physical activities in the Saudi society in terms of the type of activities that young people prefer, where they prefer to engage in and under any thermal and light conditions. The final section asks about the design of residential units in beach sports resorts, the data collected from 127 participants. Findings revealed that participants prefer outdoor activities in moderate weather and sunlight or the evening with moderate and sufficient lighting and that no beach sports resorts in the country are constructed to support sustainable design criteria for physical activity. Participants agreed that several measures that lessen tension at beach resorts and enhance movement and activity are needed by Saudi society. The study recommends designing resorts that meet the sustainable design criteria regarding physical activity in Saudi Arabia to increase physical activity to achieve psychological and physical benefits and avoid psychological and physical diseases related to physical inactivity.

Keywords: sustainable design, SDGs, active design strategies, well building, beach resort design

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Authors: Anna Marie Fisker, Daniele Sepe, Mette Bøgh Jensen, Daniela Rimei

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In the space of just a few years, the European policy framework on cultural heritage has been completely overhauled, moving towards a people-centred and holistic approach, and eliminating the divisions between the tangible, intangible and digital dimensions. The European Union regards cultural heritage as a potential shared resource, highlighting that all stakeholders share responsibility for its transmission to future generations. This new framework will potentially change the way in which cultural institutions manage, protect and provide access to their heritage. It will change the way in which citizens and communities engage with their cultural heritage and naturally influence the way that professionals deal with it. Participating in the creation of cultural heritage awareness can lead to an increased perception of its value, be it economic, social, environmental or cultural. It can also strengthen our personal identity, sense of belonging and community citizenship. Open Atelier, a Creative Europe project, is based on this foundation, with the goal through co-creation to develop the use, understanding and engagement with our cultural heritage. The project aim to transform selected parts of the heritage into an “experience lab” – an interactive, co-creative, dynamic and participatory space, where cultural heritage is the point of departure for new interactions and experiences between the audience and the museum and its professionals. Through a workshop-based approach built on interdisciplinary collaboration and co-creative processes, Open Atelier has started to design, develop, test, and evaluate a set of Experiences. The first collaborative initiative was set out in the discourse and knowledge of a highly creative period in Denmark where a specific group of Scandinavian artists, the Skagen Painters, gathered in the village of Skagen, the northernmost part of Denmark from the late 1870s until the turn of the century. The Art Museums of Skagen have a large collection of photos from the period, that has never been the subject of more thorough research. The photos display a variation of many different subjects: community, family photos, reproductions of art works, costume parties, family gatherings etc., and carry with them the energies of those peoples’ work and life and evoke instances of communication with the past. This paper is about how we in Open Atelier connect these special stories, this legacy, with another place, in another time, in another context and with another audience. The first Open Atelier Experience – the performance “Around the Lighthouse” – was an initiative resulted from the collaboration between AMAT, an Italian creative organisation, and the Art Museums of Skagen. A group of Italian artists developed a co-creative investigation and reinterpretation of a selection of these historical photos. A poetic journey through videos and voices, aimed at exploring new perspectives on the museum and its heritage. An experiment on how to create new ways to actively engage audiences in the way cultural heritage is explored, interpreted, mediated, presented, and used to examine contemporary issues. This article is about this experiment and its findings, and how different views and methodologies can be adopted to discuss the cultural heritage in museums around Europe and their connection to the community.

Keywords: cultural heritage, community, innovation, museums

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Authors: Adine Gericke, Jiri Militky, Mohanapriya Venkataraman

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Mohair, obtained from the Angora goat, is a luxury fiber and recognized as one of the best quality natural fibers. Expansion of the use of mohair into technical and functional textile products necessitates the need for a better understanding of how the use of mohair in fabrics will impact on its thermo-physiological comfort related properties. Despite its popularity, very little information is available on the quantification of the thermal and moisture management properties of mohair fabrics. This study investigated the effect of fibrous matter composition and fabric structural parameters on conductive and convective heat transfers to attain more information on the thermal comfort properties of mohair fabrics. Dry heat transfer through textiles may involve conduction through the fibrous phase, radiation through fabric interstices and convection of air within the structure. Factors that play a major role in heat transfer by conduction are fabric areal density (g/m2) and derived quantities such as cover factor and porosity. Convective heat transfer through fabrics is found in environmental conditions where there is wind-flow or the object is moving (e.g. running or walking). The thermal comfort properties of mohair fibers were objectively evaluated firstly in comparison with other textile fibers and secondly in a variety of fabric structures. Two sample sets were developed for this purpose, with fibre content, yarn structure and fabric design as main variables. SEM and microscopic images were obtained to closely examine the physical structures of the fibers and fabrics. Thermal comfort properties such as thermal resistance and thermal conductivity, as well as fabric thickness, were measured on the well-known Alambeta test instrument. Clothing insulation (clo) was calculated from the above. The thermal properties of fabrics under heat convection was evaluated using a laboratory model device developed at the Technical University of Liberec (referred to as the TP2-instrument). The effects of the different variables on fabric thermal comfort properties were analyzed statistically using TIBCO Statistica Software. The results showed that fabric structural properties, specifically sample thickness, played a significant role in determining the thermal comfort properties of the fabrics tested. It was found that regarding thermal resistance related to conductive heat flow, the effect of fiber type was not always statistically significant, probably as a result of the amount of trapped air within the fabric structure. The very low thermal conductivity of air, compared to that of the fibers, had a significant influence on the total conductivity and thermal resistance of the samples. This was confirmed by the high correlation of these factors with sample thickness. Regarding convective heat flow, the most important factor influencing the ability of the fabric to allow dry heat to move through the structure, was again fabric thickness. However, it would be wrong to totally disregard the effect of fiber composition on the thermal resistance of textile fabrics. In this study, the samples containing mohair or mohair/wool were consistently thicker than the others even though weaving parameters were kept constant. This can be ascribed to the physical properties of the mohair fibers that renders it exceptionally well towards trapping air among fibers (in a yarn) as well as among yarns (inside a fabric structure). The thicker structures trap more air to provide higher thermal insulation, but also prevent the free flow of air that allow thermal convection.

Keywords: mohair fabrics, convective heat transfer, thermal comfort properties, thermal resistance

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Authors: Chao-Yang Huang, Rwey-Hua Cherng, Chung-Lin Fu, Yuan-Lung Lo

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Solar energy is one of the replaceable choices to reduce the CO2 emission produced by conventional power plants in the modern society. As an island which is frequently visited by strong typhoons and earthquakes, it is an urgent issue for Taiwan to make an effort in revising the local regulations to strengthen the safety design of photovoltaic systems. Currently, the Taiwanese code for wind resistant design of structures does not have a clear explanation on photovoltaic systems, especially when the systems are arranged in arrayed format. Furthermore, when the arrayed photovoltaic system is mounted on the rooftop, the approaching flow is significantly altered by the building and led to different pressure pattern in the different area of the photovoltaic system. In this study, L-shape arrayed photovoltaic system is mounted on the ground of the wind tunnel and then mounted on the building rooftop. The system is consisted of 60 PV models. Each panel model is equivalent to a full size of 3.0 m in depth and 10.0 m in length. Six pressure taps are installed on the upper surface of the panel model and the other six are on the bottom surface to measure the net pressures. Wind attack angle is varied from 0° to 360° in a 10° interval for the worst concern due to wind direction. The sampling rate of the pressure scanning system is set as high enough to precisely estimate the peak pressure and at least 20 samples are recorded for good ensemble average stability. Each sample is equivalent to 10-minute time length in full scale. All the scale factors, including timescale, length scale, and velocity scale, are properly verified by similarity rules in low wind speed wind tunnel environment. The purpose of L-shape arrayed system is for the understanding the pressure characteristics at the corner area. Extreme value analysis is applied to obtain the design pressure coefficient for each net pressure. The commonly utilized Cook-and-Mayne coefficient, 78%, is set to the target non-exceedance probability for design pressure coefficients under Gumbel distribution. Best linear unbiased estimator method is utilized for the Gumbel parameter identification. Careful time moving averaging method is also concerned in data processing. Results show that when the arrayed photovoltaic system is mounted on the ground, the first row of the panels reveals stronger positive pressure than that mounted on the rooftop. Due to the flow separation occurring at the building edge, the first row of the panels on the rooftop is most in negative pressures; the last row, on the other hand, shows positive pressures because of the flow reattachment. Different areas also have different pressure patterns, which corresponds well to the regulations in ASCE7-16 describing the area division for design values. Several minor observations are found according to parametric studies, such as rooftop edge effect, parapet effect, building aspect effect, row interval effect, and so on. General comments are then made for the proposal of regulation revision in Taiwanese code.

Keywords: aerodynamic force coefficient, ground-mounted, roof-mounted, wind tunnel test, photovoltaic

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Authors: B. Sudhakara Reddy

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This study provides a snapshot of the sustainability of selected Indian cities by employing 70 indicators in four dimensions to develop an overall city sustainability index. In recent years, the concept of ‘urban sustainability’ has become prominent due to its complexity. Urban areas propel growth and at the same time poses a lot of ecological, social and infrastructural problems and risks. In case of developing countries, the high population density of and the continuous in-migration run the highest risk in natural and man-made disasters. These issues combined with the inability of policy makers in providing basic services makes the cities unsustainable. To assess whether any given policy is moving towards or against urban sustainability it is necessary to consider the relationships among its various dimensions. Hence, in recent years, while preparing the sustainability index, an integral approach involving indicators of different dimensions such as ‘economic’, ‘environmental’ and 'social' is being used. It is also important for urban planners, social analysts and other related institutions to identify and understand the relationships in this complex system. The objective of the paper is to develop a city performance index (CPI) to measure and evaluate the urban regions in terms of sustainable performances. The objectives include: i) Objective assessment of a city’s performance, ii) setting achievable goals iii) prioritise relevant indicators for improvement, iv) learning from leaders, iv) assessment of the effectiveness of programmes that results in achieving high indicator values, v) Strengthening of stakeholder participation. Using the benchmark approach, a conceptual framework is developed for evaluating 25 Indian cities. We develop City Sustainability index (CSI) in order to rank cities according to their level of sustainability. The CSI is composed of four dimensions: Economic, Environment, Social, and Institutional. Each dimension is further composed of multiple indicators: (1) Economic that considers growth, access to electricity, and telephone availability; (2) environmental that includes waste water treatment, carbon emissions, (3) social that includes, equity, infant mortality, and 4) institutional that includes, voting share of population, urban regeneration policies. The CSI, consisting of four dimensions disaggregate into 12 categories and ultimately into 70 indicators. The data are obtained from public and non-governmental organizations, and also from city officials and experts. By ranking a sample of diverse cities on a set of specific dimensions the study can serve as a baseline of current conditions and a marker for referencing future results. The benchmarks and indices presented in the study provide a unique resource for the government and the city authorities to learn about the positive and negative attributes of a city and prepare plans for a sustainable urban development. As a result of our conceptual framework, the set of criteria we suggest is somewhat different to any already in the literature. The scope of our analysis is intended to be broad. Although illustrated with specific examples, it should be apparent that the principles identified are relevant to any monitoring that is used to inform decisions involving decision variables. These indicators are policy-relevant and, hence they are useful tool for decision-makers and researchers.

Keywords: benchmark, city, indicator, performance, sustainability

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Authors: Yildiz Stella Dak, Jale Tezcan

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Ground motion models that relate a strong motion parameter of interest to a set of predictive seismological variables describing the earthquake source, the propagation path of the seismic wave, and the local site conditions constitute a critical component of seismic hazard analyses. When a sufficient number of strong motion records are available, ground motion relations are developed using statistical analysis of the recorded ground motion data. In regions lacking a sufficient number of recordings, a synthetic database is developed using stochastic, theoretical or hybrid approaches. Regardless of the manner the database was developed, ground motion relations are developed using regression analysis. Development of a ground motion relation is a challenging process which inevitably requires the modeler to make subjective decisions regarding the inclusion criteria of the recordings, the functional form of the model and the set of seismological variables to be included in the model. Because these decisions are critically important to the validity and the applicability of the model, there is a continuous interest on procedures that will facilitate the development of ground motion models. This paper proposes the use of the Least Absolute Shrinkage and Selection Operator (LASSO) in selecting the set predictive seismological variables to be used in developing a ground motion relation. The LASSO can be described as a penalized regression technique with a built-in capability of variable selection. Similar to the ridge regression, the LASSO is based on the idea of shrinking the regression coefficients to reduce the variance of the model. Unlike ridge regression, where the coefficients are shrunk but never set equal to zero, the LASSO sets some of the coefficients exactly to zero, effectively performing variable selection. Given a set of candidate input variables and the output variable of interest, LASSO allows ranking the input variables in terms of their relative importance, thereby facilitating the selection of the set of variables to be included in the model. Because the risk of overfitting increases as the ratio of the number of predictors to the number of recordings increases, selection of a compact set of variables is important in cases where a small number of recordings are available. In addition, identification of a small set of variables can improve the interpretability of the resulting model, especially when there is a large number of candidate predictors. A practical application of the proposed approach is presented, using more than 600 recordings from the National Geospatial-Intelligence Agency (NGA) database, where the effect of a set of seismological predictors on the 5% damped maximum direction spectral acceleration is investigated. The set of candidate predictors considered are Magnitude, Rrup, Vs30. Using LASSO, the relative importance of the candidate predictors has been ranked. Regression models with increasing levels of complexity were constructed using one, two, three, and four best predictors, and the models’ ability to explain the observed variance in the target variable have been compared. The bias-variance trade-off in the context of model selection is discussed.

Keywords: ground motion modeling, least absolute shrinkage and selection operator, penalized regression, variable selection

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Authors: Shereen Yehia El Ezabi

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The transition from the advanced to the superior level of Arabic proficiency is widely known to pose considerable challenges for English speaking students of Arabic as a Foreign Language (AFL). Apart from the increasing complexity of the grammar at this juncture, together with the sprawling vocabulary, to name but two of those challenges, there is also the somewhat less studied hurdle along the way to superior level proficiency, namely, the seeming opacity of many aspects of Arab/ic culture to such learners. This presentation tackles one specific dimension of such issues: religious references in literary texts. It illustrates how carefully constructed translation activities may be used to expand and deepen students’ understanding and use of them. This is shown to be vital for making the leap to the desired competency, given that such elements, as reflected in customs, traditions, institutions, worldviews, and formulaic expressions lie at the very core of Arabic culture and, as such, pervade all modes and levels of Arabic discourse. A short story from the collection “Stories from Our Alley”, by preeminent novelist Naguib Mahfouz is selected for use in this context, being particularly replete with such religious references, of which religious expressions will form the focus of the presentation. As a miniature literary work, it provides an organic whole, so to speak, within which to explore with the class the most precise denotation, as well as the subtlest connotation of each expression in an effort to reach the ‘best’ English rendering. The term ‘best’ refers to approximating the meaning in its full complexity from the source text, in this case Arabic, to the target text, English, according to the concept of equivalence in translation theory. The presentation will show how such a process generates the sort of thorough discussion and close text analysis which allows students to gain valuable insight into this central idiom of Arabic. A variety of translation methods will be highlighted, gleaned from the presenter’s extensive work with advanced/superior students in the Center for Arabic Study Abroad (CASA) program at the American University in Cairo. These begin with the literal rendering of expressions, with the purpose of reinforcing vocabulary learning and practicing the rules of derivational morphology as they form each word, since the larger context remains that of an AFL class, as opposed to a translation skills program. However, departures from the literal approach are subsequently explored by degrees, moving along the spectrum of functional and pragmatic freer translations in order to transmit the ‘real’ meaning in readable English to the target audience- no matter how culture/religion specific the expression- while remaining faithful to the original. Samples from students’ work pre and post discussion will be shared, demonstrating how class consensus is formed as to the final English rendering, proposed as the closest match to the Arabic, and shown to be the result of the above activities. Finally, a few examples of translation work which students have gone on to publish will be shared to corroborate the effectiveness of this teaching practice.

Keywords: superior level proficiency in Arabic as a foreign language, teaching Arabic as a foreign language, teaching idiomatic expressions, translation in foreign language teaching

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Authors: Muccifora S., Rinallo C., Bellani L.

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Calcium (Ca²+) is an element essential to the plant being involved in plant growth and development. At high concentrations, it is toxic and can influence every stage, process and cellular activity of plant life. Given its toxicity, cells implement mechanisms to compartmentalize calcium in a vacuole, endoplasmic reticulum, mitochondria, plastids and cell wall. One of the most effective mechanisms to reduce the excess of calcium, thus avoiding cellular damage, is its complexation with oxalic acid to form calcium oxalate crystals that are no longer osmotically or physiologically active. However, the sequestered calcium can be mobilized when the plant needs it. Calcium crystals can be accumulated in the vacuole of specialized sink-cells called idioblasts, with different crystalline forms (druse, raphyde and styloid) of diverse physiological meanings. Actinidia deliciosa cv. Hayward presents raphydes and styloid localized in idioblasts in cells of photosynthetic and non-photosynthetic tissues. The purpose of this work was to understand if there is a relationship between the age of Actinidia leaves and the presence, distribution, dimension and shape of oxalate crystals by means of light, fluorescent, polarized and transmission electron microscopy. Three vines from female plants were chosen at the beginning of the season and used throughout the study. The leaves with petioles were collected at various stages of development from the bottom to the shoot of the plants monthly from April to July. The samples were taken in corresponding areas of the central and lateral parts of the leaves and of the basal portion of the petiole. The results showed that in the leaves, the number of raphyde idioblasts decreased with the progress of the growing season, while the styloid idioblasts increased progressively, becoming very numerous in the upper nodes of July. In June and in July samples, in the vacuoles of the highest nodes, a portion regular in shape strongly stained with rubeanic acid was present. Moreover, the chlortetracycline (CTC) staining for localization of free calcium marked the wall of the idioblasts and the wall of the cells near vascular bundles. In April petiole samples, moving towards the youngest nodes, the raphydes idioblast decreased in number and in the length of the single raphydes. Besides, crystals stained with rubeanic acid appeared in the vacuoles of some cells. In June samples, numerous raphyde idioblasts oriented parallel to vascular bundles were evident. Under the electron microscope, numerous idioblasts presented not homogeneous electrondense aggregates of material, in which a few crystals (styloids) in the form of regular holes were scattered. In July samples, an increase in the number of styloid idioblasts in the youngest nodes and little masses stained with CTC near styloids were observed. Peculiar cells stained with rubeanic acid were detected and hypothesized to be involved in the formation of the idioblasts. In conclusion, in Actinidia leaves and petioles, it seems to confirm the hypothesis that the formation of styloid idioblasts can be correlated to increasing calcium levels in growing tissues.

Keywords: calcium oxalate crystals, actinidia deliciosa, light and electron microscopy, idioblasts

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Authors: Lina E. Homman, Alexis C. Edwards, Seung Bin Cho, Danielle M. Dick, Kenneth S. Kendler

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Research supports an association between alcohol problems and internalising symptoms, but the understanding of how the two phenotypes relate to each other is poor. It has been hypothesized that the relationship between the phenotypes is causal; however investigations in regards to direction are inconsistent. Clarity of the relationship between the two phenotypes may be provided by investigating the phenotypes developmental inter-relationships longitudinally. The objective of the study was to investigate a) changes in alcohol problems and internalising symptoms in college students across time and b) the direction of effect of growth between alcohol problems and internalising symptoms from late adolescent to emerging adulthood c) possible gender differences. The present study adds to the knowledge of comorbidity of alcohol problems and internalising symptoms by examining a longitudinal sample of college students and by examining the simultaneous development of the symptoms. A sample of college students is of particular interest as symptoms of both phenotypes often have their onset around this age. A longitudinal sample of college students from a large, urban, public university in the United States was used. Data was collected over a time period of 2 years at 3 time points. Latent growth models were applied to examine growth trajectories. Parallel process growth models were used to assess whether initial level and rate of change of one symptom affected the initial level and rate of change of the second symptom. Possible effects of gender and ethnicity were investigated. Alcohol problems significantly increased over time, whereas internalizing symptoms remained relatively stable. The two phenotypes were significantly correlated in each wave, correlations were stronger among males. Initial level of alcohol problems was significantly positively correlated with initial level of internalising symptoms. Rate of change of alcohol problems positively predicted rate of change of internalising symptoms for females but not for males. Rate of change of internalising symptoms did not predict rate of change of alcohol problems for either gender. Participants of Black and Asian ethnicities indicated significantly lower levels of alcohol problems and a lower increase of internalising symptoms across time, compared to White participants. Participants of Black ethnicity also reported significantly lower levels of internalising symptoms compared to White participants. The present findings provide additional support for a positive relationship between alcohol problems and internalising symptoms in youth. Our findings indicated that both internalising symptoms and alcohol problems increased throughout the sample and that the phenotypes were correlated. The findings mainly implied a bi-directional relationship between the phenotypes in terms of significant associations between initial levels as well as rate of change. No direction of causality was indicated in males but significant results were found in females where alcohol problems acted as the main driver for the comorbidity of alcohol problems and internalising symptoms; alcohol may have more detrimental effects in females than in males. Importantly, our study examined a population-based longitudinal sample of college students, revealing that the observed relationships are not limited to individuals with clinically diagnosed mental health or substance use problems.

Keywords: alcohol, comorbidity, internalising symptoms, longitudinal modelling

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Authors: A. Abdouni, C. Thieulin, M. Djaghloul, R. Vargiolu, H. Zahouani

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A decline in the main sensory modalities (vision, hearing, taste, and smell) is well reported to occur with advancing age, it is expected a similar change to occur with touch sensation and perception. In this study, we have focused on the touch sensations highlighting ageing and gender influences with in vivo systems. The touch process can be divided into two main phases: The first phase is the first contact between the finger and the object, during this contact, an adhesive force has been created which is the needed force to permit an initial movement of the finger. In the second phase, the finger mechanical properties with their surface topography play an important role in the obtained sensation. In order to understand the age and gender effects on the touch sense, we develop different ideas and systems for each phase. To better characterize the contact, the mechanical properties and the surface topography of human finger, in vivo studies on the pulp of 40 subjects (20 of each gender) of four age groups of 26±3, 35+-3, 45+-2 and 58±6 have been performed. To understand the first touch phase a classical indentation system has been adapted to measure the finger contact properties. The normal force load, the indentation speed, the contact time, the penetration depth and the indenter geometry have been optimized. The penetration depth of a glass indenter is recorded as a function of the applied normal force. Main assessed parameter is the adhesive force F_ad. For the second phase, first, an innovative approach is proposed to characterize the dynamic finger mechanical properties. A contactless indentation test inspired from the techniques used in ophthalmology has been used. The test principle is to blow an air blast to the finger and measure the caused deformation by a linear laser. The advantage of this test is the real observation of the skin free return without any outside influence. Main obtained parameters are the wave propagation speed and the Young's modulus E. Second, negative silicon replicas of subject’s fingerprint have been analyzed by a probe laser defocusing. A laser diode transmits a light beam on the surface to be measured, and the reflected signal is returned to a set of four photodiodes. This technology allows reconstructing three-dimensional images. In order to study the age and gender effects on the roughness properties, a multi-scale characterization of roughness has been realized by applying continuous wavelet transform. After determining the decomposition of the surface, the method consists of quantifying the arithmetic mean of surface topographic at each scale SMA. Significant differences of the main parameters are shown with ageing and gender. The comparison between men and women groups reveals that the adhesive force is higher for women. The results of mechanical properties show a Young’s modulus higher for women and also increasing with age. The roughness analysis shows a significant difference in function of age and gender.

Keywords: ageing, finger, gender, touch

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Authors: Leigha C. Crout

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This paper will investigate the categorical disregard of the People’s Republic of China (PRC) in establishing and maintaining a baseline standard of civil guarantees for economic migrant women and their dependents. In light of the relative forward strides in terms of policy facilitating the ascension of female workers in China, this oft-invisible subgroup of women remains neglected from the modern-day “iron rice bowl” of the self-identified communist state. This study is being undertaken to rectify the absence of data on this subject and provide a baseline for future studies on the matter, as the human rights of migrants has become an established facet of transnational dialogue and debate. The basic methodology of this research will consist of the evaluation of China’s compliance with its own national guidelines, and the eight international human rights law treaties it has ratified. Data will be extracted and cross-checked from a number of relevant sources to monitor the extent of compliance, including but by no means limited to the United Nations Human Rights Council (UNHRC) Universal Periodic Review (UPR) reports and responses, submissions and responses of international human rights treaty bodies, local and international nongovernmental organizations (NGOs) and their annual reports, and articles and commentaries authored by specialists on the modern state and implementation of Chinese law. Together, these data will illuminate the vast network of compliance that has forced many migrant women to work within situations of extreme economic precarity. The structure will proceed as follows: first, an outline of the current status of migrant workers and the enforcement of stipulated protections will be provided; next, the analysis of the oft-debated regulations directing and the outline of mandatory services guaranteed to external and internal migrants; and finally, a conclusion incorporating various recommendations to improve transparency and gradually decrease the amount of migrant work turned forced labor that typifies the economic migrant experience, especially in the case of women. The internal and international migrant workers in China are bound by different and uncomplimentary systems. The first, which governs Chinese citizens moving to different regions or provinces to find more sustainable employment (internal migrants), is called the hukou (or huji) residency system. This law enforces strict regulation of the movement of peoples, while ensuring that residents of urban areas receive preferential benefits to those received by their so-called “agricultural” resident counterparts. Given the overwhelming presence of the Communist Party of China throughout the vast state, the management of internal migrants and the disregard for foreign domestic workers is, at minimum, a surprising oversight. This paper endeavors to provide a much-needed foundation for future commentary and discussion on the treatment of female migrant workers and their families in the People’s Republic of China.

Keywords: female migrant worker’s rights, the People’s Republic of China, forced labor, Hukou residency system

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Authors: Mohammad Karimi Moridani, Mohammad Abdi Zadeh, Zahra Shahiazar Mazraeh

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In recent years, the use of intelligent systems in biomedical engineering has increased dramatically, especially in the diagnosis of various diseases. Also, due to the relatively simple recording of the electrocardiogram signal (ECG), this signal is a good tool to show the function of the heart and diseases associated with it. The aim of this paper is to design an intelligent system for automatically detecting a normal electrocardiogram signal from abnormal one. Using this diagnostic system, it is possible to identify a person's heart condition in a very short time and with high accuracy. The data used in this article are from the Physionet database, available in 2016 for use by researchers to provide the best method for detecting normal signals from abnormalities. Data is of both genders and the data recording time varies between several seconds to several minutes. All data is also labeled normal or abnormal. Due to the low positional accuracy and ECG signal time limit and the similarity of the signal in some diseases with the normal signal, the heart rate variability (HRV) signal was used. Measuring and analyzing the heart rate variability with time to evaluate the activity of the heart and differentiating different types of heart failure from one another is of interest to the experts. In the preprocessing stage, after noise cancelation by the adaptive Kalman filter and extracting the R wave by the Pan and Tampkinz algorithm, R-R intervals were extracted and the HRV signal was generated. In the process of processing this paper, a new idea was presented that, in addition to using the statistical characteristics of the signal to create a return map and extraction of nonlinear characteristics of the HRV signal due to the nonlinear nature of the signal. Finally, the artificial neural networks widely used in the field of ECG signal processing as well as distinctive features were used to classify the normal signals from abnormal ones. To evaluate the efficiency of proposed classifiers in this paper, the area under curve ROC was used. The results of the simulation in the MATLAB environment showed that the AUC of the MLP and SVM neural network was 0.893 and 0.947, respectively. As well as, the results of the proposed algorithm in this paper indicated that the more use of nonlinear characteristics in normal signal classification of the patient showed better performance. Today, research is aimed at quantitatively analyzing the linear and non-linear or descriptive and random nature of the heart rate variability signal, because it has been shown that the amount of these properties can be used to indicate the health status of the individual's heart. The study of nonlinear behavior and dynamics of the heart's neural control system in the short and long-term provides new information on how the cardiovascular system functions, and has led to the development of research in this field. Given that the ECG signal contains important information and is one of the common tools used by physicians to diagnose heart disease, but due to the limited accuracy of time and the fact that some information about this signal is hidden from the viewpoint of physicians, the design of the intelligent system proposed in this paper can help physicians with greater speed and accuracy in the diagnosis of normal and patient individuals and can be used as a complementary system in the treatment centers.

Keywords: neart rate variability, signal processing, linear and non-linear features, classification methods, ROC Curve

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Authors: Ines Oliveira, Ana Reis

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Magnetic Pulse Welding (MPW) is a cold solid-state welding process, accomplished by the electromagnetically driven, high-speed and low-angle impact between two metallic surfaces. It has the same working principle of Explosive Welding (EXW), i.e. is based on the collision of two parts at high impact speed, in this case, propelled by electromagnetic force. Under proper conditions, i.e., flyer velocity and collision point angle, a permanent metallurgical bond can be achieved between widely dissimilar metals. MPW has been considered a promising alternative to the conventional welding processes and advantageous when compared to other impact processes. Nevertheless, MPW current applications are mostly academic. Despite the existing knowledge, the lack of consensus regarding several aspects of the process calls for further investigation. As a result, the mechanical resistance, morphology and structure of the weld interface in MPW of Al/Cu dissimilar pair were investigated. The effect of process parameters, namely gap, standoff distance and energy, were studied. It was shown that welding only takes place if the process parameters are within an optimal range. Additionally, the formation of intermetallic phases cannot be completely avoided in the weld of Al/Cu dissimilar pair by MPW. Depending on the process parameters, the intermetallic compounds can appear as continuous layer or small pockets. The thickness and the composition of the intermetallic layer depend on the processing parameters. Different intermetallic phases can be identified, meaning that different temperature-time regimes can occur during the process. It is also found that lower pulse energies are preferred. The relationship between energy increase and melting is possibly related to multiple sources of heating. Higher values of pulse energy are associated with higher induced currents in the part, meaning that more Joule heating will be generated. In addition, more energy means higher flyer velocity, the air existing in the gap between the parts to be welded is expelled, and this aerodynamic drag (fluid friction) is proportional to the square of the velocity, further contributing to the generation of heat. As the kinetic energy also increases with the square of velocity, the dissipation of this energy through plastic work and jet generation will also contribute to an increase in temperature. To reduce intermetallic phases, porosity, and melt pockets, pulse energy should be minimized. The bond formation is affected not only by the gap, standoff distance, and energy but also by the mandrel’s surface conditions. No correlation was clearly identified between surface roughness/scratch orientation and joint strength. Nevertheless, the aspect of the interface (thickness of the intermetallic layer, porosity, presence of macro/microcracks) is clearly affected by the surface topology. Welding was not established on oil contaminated surfaces, meaning that the jet action is not enough to completely clean the surface.

Keywords: bonding mechanisms, impact welding, intermetallic compounds, magnetic pulse welding, wave formation

Procedia PDF Downloads 187

Authors: Sharon Harel, Rachel Kizony, Yoram Feldman, Gabi Zeilig, Mordechai Shani

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Multiple Sclerosis (MS) is a neurological disease that may cause restriction in participation in daily activities of young adults. Main symptoms include fatigue, weakness and cognitive decline. The appearance of symptoms, their severity and deterioration rate, change between patients. The challenge of health services is to provide long-term rehabilitation services to people with MS. The objective of this presentation is to describe a course of tele-rehabilitation service of a woman with MS. Methods; R is a 48 years-old woman, diagnosed with MS when she was 22. She started to suffer from weakness of her non-dominant left upper extremity about ten years after the diagnosis. She was referred to the tele-rehabilitation service by her rehabilitation team, 16 years after diagnosis. Her goals were to improve ability to use her affected upper extremity in daily activities. On admission her score in the Mini-Mental State Exam was 30/30. Her Fugl-Meyer Assessment (FMA) score of the left upper extremity was 48/60, indicating mild weakness and she had a limitation of her shoulder abduction (90 degrees). In addition, she reported little use of her arm in daily activities as shown in her responses to the Motor Activity Log (MAL) that were equal to 1.25/5 in amount and 1.37 in quality of use. R. received two 30 minutes on-line sessions per week in the tele-rehabilitation service, with the CogniMotion system. These were complemented by self-practice with the system. The CogniMotion system provides a hybrid (synchronous-asynchronous), the home-based tele-rehabilitation program to improve the motor, cognitive and functional status of people with neurological deficits. The system consists of a computer, large monitor, and the Microsoft’s Kinect 3D sensor. This equipment is located in the client’s home and connected to a clinician’s computer setup in a remote clinic via WiFi. The client sits in front of the monitor and uses his body movements to interact with games and tasks presented on the monitor. The system provides feedback in the form of ‘knowledge of results’ (e.g., the success of a game) and ‘knowledge of performance’ (e.g., alerts for compensatory movements) to enhance motor learning. The games and tasks were adapted for R. motor abilities and level of difficulty was gradually increased according to her abilities. The results of her second assessment (after 35 on-line sessions) showed improvement in her FMA score to 52 and shoulder abduction to 140 degrees. Moreover, her responses to the MAL indicated an increased amount (2.4) and quality (2.2) of use of her left upper extremity in daily activities. She reported high level of enjoyment from the treatments (5/5), specifically the combination of cognitive challenges while moving her body. In addition, she found the system easy to use as reflected by her responses to the System Usability Scale (85/100). To-date, R. continues to receive treatments in the tele-rehabilitation service. To conclude, this case report shows the potential of using tele-rehabilitation for people with MS to provide strategies to enhance the use of the upper extremity in daily activities as well as for maintaining motor function.

Keywords: motor function, multiple-sclerosis, tele-rehabilitation, daily activities

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Authors: Mamunur Rashid, Jialin Yan

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The current years have witnessed a rapid evolution and integration of artificial intelligence (AI) in various fields, prominently influencing the education industry. Acknowledging this transformative wave, AI tools like ChatGPT and Grammarly have undeniably introduced perspectives and skills, enriching the educational experiences of higher education students. The prevalence of AI utilization in higher education also drives an increasing number of researchers' attention in various dimensions. Departments, offices, and professors in universities also designed and released a set of policies and guidelines on using AI effectively. In regard to this, the study targets exploring and analyzing graduate students' perspectives regarding AI guidelines set by teachers. A mixed-methods study will be mainly conducted in this study, employing in-depth interviews and focus groups to investigate and collect students' perspectives. Relevant materials, such as syllabi and course instructions, will also be analyzed through the documentary analysis to facilitate understanding of the study. Surveys will also be used for data collection and students' background statistics. The integration of both interviews and surveys will provide a comprehensive array of student perspectives across various academic disciplines. The study is anchored in the theoretical framework of self-determination theory (SDT), which emphasizes and explains the students' perspective under the AI guidelines through three core needs: autonomy, competence, and relatedness. This framework is instrumental in understanding how AI guidelines influence students' intrinsic motivation and sense of empowerment in their learning environments. Through qualitative analysis, the study reveals a sense of confusion and uncertainty among students regarding the appropriate application and ethical considerations of AI tools, indicating potential challenges in meeting their needs for competence and autonomy. The quantitative data further elucidates these findings, highlighting a significant communication gap between students and educators in the formulation and implementation of AI guidelines. The critical findings of this study mainly come from two aspects: First, the majority of graduate students are uncertain and confused about relevant AI guidelines given by teachers. Second, this study also demonstrates that the design and effectiveness of course materials, such as the syllabi and instructions, also need to adapt in regard to AI policies. It indicates that certain of the existing guidelines provided by teachers lack consideration of students' perspectives, leading to a misalignment with students' needs for autonomy, competence, and relatedness. More emphasize and efforts need to be dedicated to both teacher and student training on AI policies and ethical considerations. To conclude, in this study, graduate students' perspectives on teacher-provided AI guidelines are explored and reflected upon, calling for additional training and strategies to improve how these guidelines can be better disseminated for their effective integration and adoption. Although AI guidelines provided by teachers may be helpful and provide new insights for students, educational institutions should take a more anchoring role to foster a motivating, empowering, and student-centered learning environment. The study also provides some relevant recommendations, including guidance for students on the ethical use of AI and AI policy training for teachers in higher education.

Keywords: higher education policy, graduate students’ perspectives, higher education teacher, AI guidelines, AI in education

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Authors: Isobel M. Thompson, Dorian Audot, Dominic Hudson, Martin Warner, Joseph Banks

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Underwater fly kick is an essential skill in swimming, which can have a considerable impact upon overall race performance in competition, especially in sprint events. Reduced wave drags acting upon the body under the surface means that the underwater fly kick will potentially be the fastest the swimmer is travelling throughout the race. It is therefore critical to understand fly kicking techniques and determining biomechanical factors involved in the performance. Most previous studies assessing fly kick kinematics have focused on two-dimensional analysis; therefore, the three-dimensional elements of the underwater fly kick techniques are not well understood. Those studies that have investigated fly kicking techniques using three-dimensional methodologies have not reported full three-dimensional kinematics for the techniques observed, choosing to focus on one or two joints. There has not been a direct comparison completed on the results obtained using two-dimensional and three-dimensional analysis, and how these different approaches might affect the interpretation of subsequent results. The aim of this research is to quantify the differences in kinematics observed in underwater fly kicks obtained from both two and three-dimensional analyses of the same test conditions. In order to achieve this, a six-camera underwater Qualisys system was used to develop an experimental methodology suitable for assessing the kinematics of swimmer’s starts and turns. The cameras, capturing at a frequency of 100Hz, were arranged along the side of the pool spaced equally up to 20m creating a capture volume of 7m x 2m x 1.5m. Within the measurement volume, error levels were estimated at 0.8%. Prior to pool trials, participants completed a landside calibration in order to define joint center locations, as certain markers became occluded once the swimmer assumed the underwater fly kick position in the pool. Thirty-four reflective markers were placed on key anatomical landmarks, 9 of which were then removed for the pool-based trials. The fly-kick swimming conditions included in the analysis are as follows: maximum effort prone, 100m pace prone, 200m pace prone, 400m pace prone, and maximum pace supine. All trials were completed from a push start to 15m to ensure consistent kick cycles were captured. Both two-dimensional and three-dimensional kinematics are calculated from joint locations, and the results are compared. Key variables reported include kick frequency and kick amplitude, as well as full angular kinematics of the lower body. Key differences in these variables obtained from two-dimensional and three-dimensional analysis are identified. Internal rotation (up to 15º) and external rotation (up to -28º) were observed using three-dimensional methods. Abduction (5º) and adduction (15º) were also reported. These motions are not observed in the two-dimensional analysis. Results also give an indication of different techniques adopted by swimmers at various paces and orientations. The results of this research provide evidence of the strengths of both two dimensional and three dimensional motion capture methods in underwater fly kick, highlighting limitations which could affect the interpretation of results from both methods.

Keywords: swimming, underwater fly kick, performance, motion capture

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Authors: Armin Nabaei, M. Omair Ahmad, M. N. S. Swamy

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Many facial expression and emotion recognition methods in the traditional approaches of using LDA, PCA, and EBGM have been proposed. In recent years deep learning models have provided a unique platform addressing by automatically extracting the features for the detection of facial expression and emotions. However, deep networks require large training datasets to extract automatic features effectively. In this work, we propose an efficient emotion detection algorithm using face images when only small datasets are available for training. We design a deep network whose feature extraction capability is enhanced by utilizing several parallel modules between the input and output of the network, each focusing on the extraction of different types of coarse features with fined grained details to break the symmetry of produced information. In fact, we leverage long range dependencies, which is one of the main drawback of CNNs. We develop this work by introducing a Dynamic Soft-Margin SoftMax.The conventional SoftMax suffers from reaching to gold labels very soon, which take the model to over-fitting. Because it’s not able to determine adequately discriminant feature vectors for some variant class labels. We reduced the risk of over-fitting by using a dynamic shape of input tensor instead of static in SoftMax layer with specifying a desired Soft- Margin. In fact, it acts as a controller to how hard the model should work to push dissimilar embedding vectors apart. For the proposed Categorical Loss, by the objective of compacting the same class labels and separating different class labels in the normalized log domain.We select penalty for those predictions with high divergence from ground-truth labels.So, we shorten correct feature vectors and enlarge false prediction tensors, it means we assign more weights for those classes with conjunction to each other (namely, “hard labels to learn”). By doing this work, we constrain the model to generate more discriminate feature vectors for variant class labels. Finally, for the proposed optimizer, our focus is on solving weak convergence of Adam optimizer for a non-convex problem. Our noteworthy optimizer is working by an alternative updating gradient procedure with an exponential weighted moving average function for faster convergence and exploiting a weight decay method to help drastically reducing the learning rate near optima to reach the dominant local minimum. We demonstrate the superiority of our proposed work by surpassing the first rank of three widely used Facial Expression Recognition datasets with 93.30% on FER-2013, and 16% improvement compare to the first rank after 10 years, reaching to 90.73% on RAF-DB, and 100% k-fold average accuracy for CK+ dataset, and shown to provide a top performance to that provided by other networks, which require much larger training datasets.

Keywords: computer vision, facial expression recognition, machine learning, algorithms, depp learning, neural networks

Procedia PDF Downloads 53

Authors: Charlotte Dreger, Erik Bollaert

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This paper presents two environmentally-friendly coastal structures realized on the Lake of Neuchâtel. Both structures reflect current environmental issues of concern on the lake and have been strongly affected by extreme meteorological conditions between their period of design and their actual operational period. The Lake of Neuchatel is one of the biggest Swiss lakes and measures around 38 km in length and 8.2 km in width, for a maximum water depth of 152 m. Its particular topographical alignment, situated in between the Swiss Plateau and the Jura mountains, combines strong winds and large fetch values, resulting in significant wave heights during storm events at both north-east and south-west lake extremities. In addition, due to flooding concerns, historically, lake levels have been lowered by several meters during the Jura correction works in the 19th and 20th century. Hence, during storm events, continuous erosion of the vulnerable molasse shorelines and sand banks generate frequent and abundant littoral transport from the center of the lake to its extremities. This phenomenon does not only cause disturbances of the ecosystem, but also generates numerous problems at natural or man-made infrastructures located along the shorelines, such as reed plants, harbor entrances, canals, etc. A first example is provided at the southwestern extremity, near the city of Yverdon, where an ensemble of 11 small islands, the Iles des Vernes, have been artificially created in view of enhancing biological conditions and food availability for bird species during their migration process, replacing at the same time two larger islands that were affected by lack of morphodynamics and general vegetalization of their surfaces. The article will present the concept and dimensioning of these islands based on 2D numerical modelling, as well as the realization and follow-up campaigns. In particular, the influence of several major storm events that occurred immediately after the works will be pointed out. Second, a sediment retention dike is discussed at the northeastern extremity, at the entrance of the Canal de la Broye into the lake. This canal is heavily used for navigation and suffers from frequent and significant sedimentation at its outlet. The new coastal structure has been designed to minimize sediment deposits around the exutory of the canal into the lake, by retaining the littoral transport during storm events. The article will describe the basic assumptions used to design the dike, as well as the construction works and follow-up campaigns. Especially the huge influence of changing meteorological conditions on the littoral transport of the Lake of Neuchatel since project design ten years ago will be pointed out. Not only the intensity and frequency of storm events are increasing, but also the main wind directions alter, affecting in this way the efficiency of the coastal structure in retaining the sediments.

Keywords: meteorological evolution, sediment transport, lake of Neuchatel, numerical modelling, environmental measures

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Authors: Sricheta Chowdhury

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To require a woman to choose between her work and her personal life is the most acute form of discrimination that can be meted out against her. No woman should be given a choice to choose between her motherhood and her career at Bar, yet that is the most detrimental discrimination that has been happening in Indian Bar, which no one has questioned so far. The falling number of women in practice is a reality that isn’t garnering much attention given the sharp rise in women studying law but is not being able to continue in the profession. Moving from a colonial misogynist whim to a post-colonial “new-age construct of Indian woman” façade, the policymakers of the Indian Judiciary have done nothing so far to decolonize itself from its rudimentary understanding of ‘equality of gender’ when it comes to the legal profession. Therefore, when Indian jurisprudence was (and is) swooning to the sweeping effect of transformative constitutionalism in the understanding of equality as enshrined under the Indian Constitution, one cannot help but question why the legal profession remained out of brushing effect of achieving substantive equality. The Airline industry’s discriminatory policies were not spared from criticism, nor were the policies where women’s involvement in any establishment serving liquor (Anuj Garg case), but the judicial practice did not question the stereotypical bias of gender and unequal structural practices until recently. That necessitates the need to examine the existing Bar policies and the steps taken by the regulatory bodies in assessing the situations that are in favor or against the purpose of furthering women’s issues in present-day India. From a comparative feminist point of concern, South Africa’s pro-women Bar policies are attractive to assess their applicability and extent in terms of promoting inclusivity at the Bar. This article intends to tap on these two countries’ potential in carving a niche in giving women an equal platform to play a substantive role in designing governance policies through the Judiciary. The article analyses the current gender composition of the legal profession while endorsing the concept of substantive equality as a requisite in designing an appropriate appointment process of the judges. It studies the theoretical framework on gender equality, examines the international and regional instruments and analyses the scope of welfare policies that Indian legal and regulatory bodies can undertake towards a transformative initiative in re-modeling the Judiciary to a more diverse and inclusive institution. The methodology employs a comparative and analytical understanding of doctrinal resources. It makes quantitative use of secondary data and qualitative use of primary data collected for determining the present status of Indian women legal practitioners and judges. With respect to quantitative data, statistics on the representation of women as judges and chief justices and senior advocates from their official websites from 2018 till present have been utilized. In respect of qualitative data, results of the structured interviews conducted through open and close-ended questions with retired lady judges of the higher judiciary and senior advocates of the Supreme Court of India, contacted through snowball sampling, are utilized.

Keywords: gender, higher judiciary, legal profession, representation, substantive equality

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Authors: Safaa M. Hassan; Safwat S. Gabr, Mohamed F. Sadek

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This study is proposed for the lithological and iron oxides detection in the old mine areas of El-Bahariya Depression, Western Desert, using ASTER and Landsat-8 remote sensing data. Four old iron ore occurrences, namely; El-Gedida, El-Haraa, Ghurabi, and Nasir mine areas found in the El-Bahariya area. This study aims to find new high potential areas for iron mineralization around El-Baharyia depression. Image processing methods such as principle component analysis (PCA) and band ratios (b4/b5, b5/b6, b6/b7, and 4/2, 6/7, band 6) images were used for lithological identification/mapping that includes the iron content in the investigated area. ASTER and Landsat-8 visible and short-wave infrared data found to help mapping the ferruginous sandstones, iron oxides as well as the clay minerals in and around the old mines area of El-Bahariya depression. Landsat-8 band ratio and the principle component of this study showed well distribution of the lithological units, especially ferruginous sandstones and iron zones (hematite and limonite) along with detection of probable high potential areas for iron mineralization which can be used in the future and proved the ability of Landsat-8 and ASTER data in mapping these features. Minimum Noise Fraction (MNF), Mixture Tuned Matched Filtering (MTMF), pixel purity index methods as well as Spectral Ange Mapper classifier algorithm have been successfully discriminated the hematite and limonite content within the iron zones in the study area. Various ASTER image spectra and ASD field spectra of hematite and limonite and the surrounding rocks are compared and found to be consistent in terms of the presence of absorption features at range from 1.95 to 2.3 μm for hematite and limonite. Pixel purity index algorithm and two sub-pixel spectral methods, namely Mixture Tuned Matched Filtering (MTMF) and matched filtering (MF) methods, are applied to ASTER bands to delineate iron oxides (hematite and limonite) rich zones within the rock units. The results are validated in the field by comparing image spectra of spectrally anomalous zone with the USGS resampled laboratory spectra of hematite and limonite samples using ASD measurements. A number of iron oxides rich zones in addition to the main surface exposures of the El-Gadidah Mine, are confirmed in the field. The proposed method is a successful application of spectral mapping of iron oxides deposits in the exposed rock units (i.e., ferruginous sandstone) and present approach of both ASTER and ASD hyperspectral data processing can be used to delineate iron-rich zones occurring within similar geological provinces in any parts of the world.

Keywords: Landsat-8, ASTER, lithological mapping, iron exploration, western desert

Procedia PDF Downloads 123

Authors: Panagiotis Gkekas, Christos Sougles, Dionysios Kehagias, Dimitrios Tzovaras

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This paper presents the architecture of the “Intelligent cooperative integrated system for road safety and road infrastructure maintenance towards 2020” (ODOS2020) advanced infrastructure, which implements a number of cooperative ITS applications based on Internet of Things and Infrastructure-to-Vehicle (V2I) technologies with the purpose to enhance the active road safety level of vehicles through the provision of a fully automated V2I environment. The primary objective of the ODOS2020 project is to contribute to increased road safety but also to the optimization of time for maintenance of road infrastructure. The integrated technological solution presented in this paper addresses all types of vehicles and requires minimum vehicle equipment. Thus, the ODOS2020 comprises a low-cost solution, which is one of its main benefits. The system architecture includes an integrated notification system to transmit personalized information on road, traffic, and environmental conditions, in order for the drivers to receive real-time and reliable alerts concerning upcoming critical situations. The latter include potential dangers on the road, such as obstacles or road works ahead, extreme environmental conditions, etc., but also informative messages, such as information on upcoming tolls and their charging policies. At the core of the system architecture lies an integrated sensorial network embedded in special road infrastructures (strips) that constantly collect and transmit wirelessly information about passing vehicles’ identification, type, speed, moving direction and other traffic information in combination with environmental conditions and road wear monitoring and predictive maintenance data. Data collected from sensors is transmitted by roadside infrastructure, which supports a variety of communication technologies such as ITS-G5 (IEEE-802.11p) wireless network and Internet connectivity through cellular networks (3G, LTE). All information could be forwarded to both vehicles and Traffic Management Centers (TMC) operators, either directly through the ITS-G5 network, or to smart devices with Internet connectivity, through cloud-based services. Therefore, through its functionality, the system could send personalized notifications/information/warnings and recommendations for upcoming events to both road users and TMC operators. In the course of the ODOS2020 project pilot operation has been conducted to allow drivers of both C-ITS equipped and non-equipped vehicles to experience the provided added value services. For non-equipped vehicles, the provided information is transmitted to a smartphone application. Finally, the ODOS2020 system and infrastructure is appropriate for installation on both urban, rural, and highway environments. The paper presents the various parts of the system architecture and concludes by outlining the various challenges that had to be overcome during its design, development, and deployment in a real operational environment. Acknowledgments: Work presented in this paper was co-financed by the European Regional Development Fund of the European Union and Greek national funds through the Operational Program Competitiveness, Entrepreneurship and Innovation (call RESEARCH–CREATE–INNOVATE) under contract no. Τ1EDK-03081 (project ODOS2020).

Keywords: infrastructure to vehicle, intelligent transportation systems, internet of things, road safety

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Authors: Pedro B. Antunes, Paulo J. Ramísio

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Road runoff is a linear source of diffuse pollution that can cause significant environmental impacts. During rainfall events, pollutants from both stationary and mobile sources, which have accumulated on the road surface, are dragged through the superficial runoff. Road runoff in coastal zones may present high levels of salinity and chlorides due to the proximity of the sea and transported marine aerosols. Appearing to be correlated to this process, organic matter concentration may also be significant. This study assesses this phenomenon with the purpose of identifying the relationships between monitored water quality parameters and intrinsic site variables. To achieve this objective, an extensive monitoring program was conducted on a Portuguese coastal highway. The study included thirty rainfall events, in different weather, traffic and salt deposition conditions in a three years period. The evaluations of various water quality parameters were carried out in over 200 samples. In addition, the meteorological, hydrological and traffic parameters were continuously measured. The salt deposition rates (SDR) were determined by means of a wet candle device, which is an innovative feature of the monitoring program. The SDR, variable throughout the year, appears to show a high correlation with wind speed and direction, but mostly with wave propagation, so that it is lower in the summer, in spite of the favorable wind direction in the case study. The distance to the sea, topography, ground obstacles and the platform altitude seems to be also relevant. It was confirmed the high salinity in the runoff, increasing the concentration of the water quality parameters analyzed, with significant amounts of seawater features. In order to estimate the correlations and patterns of different water quality parameters and variables related to weather, road section and salt deposition, the study included exploratory data analysis using different techniques (e.g. Pearson correlation coefficients, Cluster Analysis and Principal Component Analysis), confirming some specific features of the investigated road runoff. Significant correlations among pollutants were observed. Organic matter was highlighted as very dependent of salinity. Indeed, data analysis showed that some important water quality parameters could be divided into two major clusters based on their correlations to salinity (including organic matter associated parameters) and total suspended solids (including some heavy metals). Furthermore, the concentrations of the most relevant pollutants seemed to be very dependent on some meteorological variables, particularly the duration of the antecedent dry period prior to each rainfall event and the average wind speed. Based on the results of a monitoring case study, in a coastal zone, it was proven that SDR, associated with the hydrological characteristics of road runoff, can contribute for a better knowledge of the runoff characteristics, and help to estimate the specific nature of the runoff and related water quality parameters.

Keywords: coastal zones, monitoring, road runoff pollution, salt deposition

Procedia PDF Downloads 214

Authors: Ado Ismail Sabo

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Statement of the Problem: The global trend in tertiary education institutions today is changing and moving towards engagement, promotion and marketing. The reason is to upscale reputation and impact positioning. More prominently, existing rivalry today seeks to draw-in the best and brightest students. A university or college is no longer just an institution of higher learning, but one adapting additional business nomenclature. Therefore, huge financial resources are invested by educational institutions to polish their image and improve their global and national ranking. In Nigeria, which boasts of a vast population of over 180 million people, some of whose patronage can bolster its education sector; standard of education continues to decline. Today, some Nigerian tertiary education institutions are shadows of their pasts, in terms of academic excellence. Quality has been relinquished because of the unquenchable quest by government officials, some civil servants, school heads and educators to amass wealth. It is very difficult to gain student satisfaction and their loyalty. Some of the student’s loyalties factor towards public higher educational institutions might be confusing. It is difficult to understand the extent to which students are satisfy on many needs. Some students might feel satisfy with the academic lecturers only, whereas others may want everything, and others will never satisfy. Due to these problems, this research aims to uncover the crucial factors influencing student loyalty and to examine if students’ satisfaction might impact mediate the relationship between service quality, organisational image and students’ loyalty towards public higher education institutions in Kano State, Nigeria. The significance of the current study is underscored by the paucity of similar research in the subject area and public tertiary education in a developing country like Nigeria as shown in existing literature. Methodology: The current study was undertaken by quantitative research methodology. Sample of 600 valid responses were obtained within the study population comprising six selected public higher education institutions in Kano State, Nigeria. These include: North West University Kano, Bayero University Kano, School of Management Studies Kano, School of Technology Kano, Sa’adatu Rimi College Kano and Federal College of Education (FCE) Kano. Four main hypotheses were formulated and tested using structural equation modeling techniques with Analysis of Moment Structure (AMOS Version 22.0). Results: Analysis of the data provided support for the main issue of this study, and the following findings are established: “Student Satisfaction mediates the relationship between Service Quality and Student Loyalty”, “Student Satisfaction mediates the relationship between Organizational Image and Student Loyalty” respectively. The findings of this study contributed to the theoretical implication which proposed a structural model that examined the relationships among overall Organizational image, service quality, student satisfaction and student loyalty. Conclusion: In addition, the findings offered a better insight to the managerial (higher institution of learning service providers) by focusing on portraying the image of service quality with student satisfaction in improving the quality of student loyalty.

Keywords: student loyalty, service quality, student satisfaction, organizational image

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Authors: Deepak Loura

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The most contemporary method of producing horticulture crops both qualitatively and quantitatively is protected cultivation, or greenhouse cultivation, which has gained widespread acceptance in recent decades. Protected farming, commonly referred to as controlled environment agriculture (CEA), is extremely productive, land- and water-wise, as well as environmentally friendly. The technology entails growing horticulture crops in a controlled environment where variables such as temperature, humidity, light, soil, water, fertilizer, etc. are adjusted to achieve optimal output and enable a consistent supply of them even during the off-season. Over the past ten years, protected cultivation of high-value crops and cut flowers has demonstrated remarkable potential. More and more agricultural and horticultural crop production systems are moving to protected environments as a result of the growing demand for high-quality products by global markets. By covering the crop, it is possible to control the macro- and microenvironments, enhancing plant performance and allowing for longer production times, earlier harvests, and higher yields of higher quality. These shielding features alter the environment of the plant while also offering protection from wind, rain, and insects. Protected farming opens up hitherto unexplored opportunities in agriculture as the liberalised economy and improved agricultural technologies advance. Typically, the revenues from fruit, vegetable, and flower crops are 4 to 8 times higher than those from other crops. If any of these high-value crops are cultivated in protected environments like greenhouses, net houses, tunnels, etc., this profit can be multiplied. Vegetable and cut flower post-harvest losses are extremely high (20–0%), however sheltered growing techniques and year-round cropping can greatly minimize post-harvest losses and enhance yield by 5–10 times. Seasonality and weather have a big impact on the production of vegetables and flowers. The variety of their products results in significant price and quality changes for vegetables. For the application of current technology in crop production, achieving a balance between year-round availability of vegetables and flowers with minimal environmental impact and remaining competitive is a significant problem. The future of agriculture will be protected since population growth is reducing the amount of land that may be held. Protected agriculture is a particularly profitable endeavor for tiny landholdings. Small greenhouses, net houses, nurseries, and low tunnel greenhouses can all be built by farmers to increase their income. Protected agriculture is also aided by the rise in biotic and abiotic stress factors. As a result of the greater productivity levels, these technologies are not only opening up opportunities for producers with larger landholdings, but also for those with smaller holdings. Protected cultivation can be thought of as a kind of precise, forward-thinking, parallel agriculture that covers almost all aspects of farming and is rather subject to additional inspection for technical applicability to circumstances, farmer economics, and market economics.

Keywords: protected cultivation, horticulture, greenhouse, vegetable, controlled environment agriculture

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Authors: Maria Amelia V. C. Araujo, Billy J. Araujo, Brian Greenwood

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The flow over a backward-facing step is characterized by the presence of flow separation, recirculation and reattachment, for a simple geometry. This type of fluid behaviour takes place in many practical engineering applications, hence the reason for being investigated. Historically, fluid flows over a backward-facing step have been examined in many experiments using a variety of measuring techniques such as laser Doppler velocimetry (LDV), hot-wire anemometry, particle image velocimetry or hot-film sensors. However, some of these techniques cannot conveniently be used in separated flows or are too complicated and expensive. In this work, the applicability of the acoustic Doppler velocimetry (ADV) technique is investigated to such type of flows, at various Reynolds numbers corresponding to different flow regimes. The use of this measuring technique in separated flows is very difficult to find in literature. Besides, most of the situations where the Reynolds number effect is evaluated in separated flows are in numerical modelling. The ADV technique has the advantage in providing nearly non-invasive measurements, which is important in resolving turbulence. The ADV Nortek Vectrino+ was used to characterize the flow, in a recirculating laboratory flume, at various Reynolds Numbers (Reh = 3738, 5452, 7908 and 17388) based on the step height (h), in order to capture different flow regimes, and the results compared to those obtained using other measuring techniques. To compare results with other researchers, the step height, expansion ratio and the positions upstream and downstream the step were reproduced. The post-processing of the AVD records was performed using a customized numerical code, which implements several filtering techniques. Subsequently, the Vectrino noise level was evaluated by computing the power spectral density for the stream-wise horizontal velocity component. The normalized mean stream-wise velocity profiles, skin-friction coefficients and reattachment lengths were obtained for each Reh. Turbulent kinetic energy, Reynolds shear stresses and normal Reynolds stresses were determined for Reh = 7908. An uncertainty analysis was carried out, for the measured variables, using the moving block bootstrap technique. Low noise levels were obtained after implementing the post-processing techniques, showing their effectiveness. Besides, the errors obtained in the uncertainty analysis were relatively low, in general. For Reh = 7908, the normalized mean stream-wise velocity and turbulence profiles were compared directly with those acquired by other researchers using the LDV technique and a good agreement was found. The ADV technique proved to be able to characterize the flow properly over a backward-facing step, although additional caution should be taken for measurements very close to the bottom. The ADV measurements showed reliable results regarding: a) the stream-wise velocity profiles; b) the turbulent shear stress; c) the reattachment length; d) the identification of the transition from transitional to turbulent flows. Despite being a relatively inexpensive technique, acoustic Doppler velocimetry can be used with confidence in separated flows and thus very useful for numerical model validation. However, it is very important to perform adequate post-processing of the acquired data, to obtain low noise levels, thus decreasing the uncertainty.

Keywords: ADV, experimental data, multiple Reynolds number, post-processing

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Authors: Samuel McLennan, Tane Moleta, Andre Brown, Marc Aurel Schnabel

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The development of Ecclesiastical buildings within New Zealand has produced some unique design characteristics that take influence from both international styles and local building methods. What this research looks at is how procedural modelling can be used to define such common characteristics and understand how they are shared and developed within different examples of a similar architectural style. This will be achieved through the creation of procedural digital reconstructions of the various timber Gothic Churches built during the 19th century in the city of Wellington, New Zealand. ‘Procedural modelling’ is a digital modelling technique that has been growing in popularity, particularly within the game and film industry, as well as other fields such as industrial design and architecture. Such a design method entails the creation of a parametric ‘ruleset’ that can be easily adjusted to produce many variations of geometry, rather than a single geometry as is typically found in traditional CAD software. Key precedents within this area of digital heritage includes work by Haegler, Müller, and Gool, Nicholas Webb and Andre Brown, and most notably Mark Burry. What these precedents all share is how the forms of the reconstructed architecture have been generated using computational rules and an understanding of the architects’ geometric reasoning. This is also true within this research as Gothic architecture makes use of only a select range of forms (such as the pointed arch) that can be accurately replicated using the same standard geometric techniques originally used by the architect. The methodology of this research involves firstly establishing a sample group of similar buildings, documenting the existing samples, researching any lost samples to find evidence such as architectural plans, photos, and written descriptions, and then culminating all the findings into a single 3D procedural asset within the software ‘Houdini’. The end result will be an adjustable digital model that contains all the architectural components of the sample group, such as the various naves, buttresses, and windows. These components can then be selected and arranged to create visualisations of the sample group. Because timber gothic churches in New Zealand share many details between designs, the created collection of architectural components can also be used to approximate similar designs not included in the sample group, such as designs found beyond the Wellington Region. This creates an initial library of architectural components that can be further expanded on to encapsulate as wide of a sample size as desired. Such a methodology greatly improves upon the efficiency and adjustability of digital modelling compared to current practices found in digital heritage reconstruction. It also gives greater accuracy to speculative design, as a lack of evidence for lost structures can be approximated using components from still existing or better-documented examples. This research will also bring attention to the cultural significance these types of buildings have within the local area, addressing the public’s general unawareness of architectural history that is identified in the Wellington based research ‘Moving Images in Digital Heritage’ by Serdar Aydin et al.

Keywords: digital forensics, digital heritage, gothic architecture, Houdini, procedural modelling

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Authors: Rama Munajat

Abstract:

Discourse information levels may be viewed from either a background-foreground distinction or a multi-level perspective, and cross-linguistic studies on this area suggest that each information level is marked by a specific linguistic device. In this sense, Sundanese, spoken in Indonesia’s West Javanese Province, further differentiates the background and foreground information into ordinary and significant types. This paper will report an ongoing shift from particle-to-active voice marking in the way Sundanese signals foregrounding events. The shift relates to decades of contact with Bahasa Indonesia (Indonesia’s official language) and linguistic compatibility between the two surface marking strategies. Representative data analyzed include three groups of short stories in both Sundanese and Bahasa Indonesia (Indonesian) published in three periods: before 1945, 1965-2006, and 2016-2019. In the first group of Sundanese data, forward-moving events dominantly appear in particle KA (Kecap Anteuran, word-accompanying) constructions, where the KA represents different particles that co-occur with a special group of verbs. The second group, however, shows that the foregrounded events are more frequently described in active-voice forms with a subject-predicate (SP) order. Subsequently, the third offers stronger evidence for the use of the SP structure. As for the Indonesian data, the foregrounding events in the first group occur in verb-initial and passive-voice constructions, while in the second and third, the events more frequently appear in active-voice structures (subject-predicate sequence). The marking shift above suggests a structural influence from Indonesian, stemmed from generational differences among authors of the Sundanese short stories, particularly related to their education and language backgrounds. The first group of short stories – published before 1945 or before Indonesia's independence from Dutch – were written by native speakers of Sundanese who spoke Indonesian as a foreign language and went through the Dutch education system. The second group of authors, on the other hand, represents a generation of Sundanese native speakers who spoke Indonesian as a second language. Finally, the third group consists of authors who are bilingual speakers of both Sundanese and Indonesian. The data suggest that the last two groups of authors completed the Indonesian education system. With these, the use of subject-predicate sequences to denote foregrounding events began to appear more frequently in the second group and then became more dominant in those of the third. The coded data also signify that cohesion, coherence, and pragmatic purposes in Particle KA constructions are intact in their respective active-voice structure counterparts. For instance, the foregrounding events in Particle KA constructions occur in Sentence-initial KA and Pre-verbal KA forms, whereas those in the active-voice are described in Subject-Predicate (SP) and Zero-Subject active-voice patterns. Cross-language data further demonstrate that the Sentence-initial KA and the SP active-voice structures each contain an overt noun phrase (NP) co-referential with one of the entities introduced in a preceding context. Similarly, the pre-verbal KA and Zero-Subject active-voice patterns have a deleted noun phrase unambiguously referable to the only one entity previously mentioned. The presence and absence of an NP inform a pragmatic strategy to place prominence on topic/given and comment/new information, respectively.

Keywords: discourse analysis, foregrounding marking, pragmatics, language contact

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Authors: Bin Shi, Mouhab Meshreki, Grégoire Bazin, Helmi Attia

Abstract:

Large monolithic components are widely used in the aerospace industry in order to reduce airplane weight. Milling is an important operation in manufacturing of the monolithic parts. More than 90% of the material could be removed in the milling operation to obtain the final shape. This results in low rigidity and post-machining distortion. The post-machining distortion is the deviation of the final shape from the original design after releasing the clamps. It is a major challenge in machining of the monolithic parts, which costs billions of economic losses every year. Three sources are directly related to the part distortion, including initial residual stresses (RS) generated from previous manufacturing processes, machining-induced RS and thermal load generated during machining. A finite element model was developed to simulate a milling process and predicate the post-machining distortion. In this study, a rolled-aluminum plate AA7175 with a thickness of 60 mm was used for the raw block. The initial residual stress distribution in the block was measured using a layer-removal method. A stress-mapping technique was developed to implement the initial stress distribution into the part. It is demonstrated that this technique significantly accelerates the simulation time. Machining-induced residual stresses on the machined surface were measured using MTS3000 hole-drilling strain-gauge system. The measured RS was applied on the machined surface of a plate to predict the distortion. The predicted distortion was compared with experimental results. It is found that the effect of the machining-induced residual stress on the distortion of a thick plate is very limited. The distortion can be ignored if the wall thickness is larger than a certain value. The RS generated from the thermal load during machining is another important factor causing part distortion. Very limited number of research on this topic was reported in literature. A coupled thermo-mechanical FE model was developed to evaluate the thermal effect on the plastic deformation of a plate. A moving heat source with a feed rate was used to simulate the dynamic cutting heat in a milling process. When the heat source passed the part surface, a small layer was removed to simulate the cutting operation. The results show that for different feed rates and plate thicknesses, the plastic deformation/distortion occurs only if the temperature exceeds a critical level. It was found that the initial residual stress has a major contribution to the part distortion. The machining-induced stress has limited influence on the distortion for thin-wall structure when the wall thickness is larger than a certain value. The thermal load can also generate part distortion when the cutting temperature is above a critical level. The developed numerical model was employed to predict the distortion of a frame part with complex structures. The predictions were compared with the experimental measurements, showing both are in good agreement. Through optimization of the position of the part inside the raw plate using the developed numerical models, the part distortion can be significantly reduced by 50%.

Keywords: modelling, monolithic parts, optimization, post-machining distortion, residual stresses

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Authors: Brayden Mi

Abstract:

Reverse time migration has been widely used in the Petroleum exploration industry to reveal subsurface images and to detect rock and fluid properties since the early 1980s. The seismic technology involves the construction of a velocity model through interpretive model construction, seismic tomography, or full waveform inversion, and the application of the reverse-time propagation of acquired seismic data and the original wavelet used in the acquisition. The methodology has matured from 2D, simple media to present-day to handle full 3D imaging challenges in extremely complex geological conditions. Conventional Ultrasound computed tomography (USCT) utilize travel-time-inversion to reconstruct the velocity structure of an organ. With the velocity structure, USCT data can be migrated with the “bend-ray” method, also known as migration. Its seismic application counterpart is called Kirchhoff depth migration, in which the source of reflective energy is traced by ray-tracing and summed to produce a subsurface image. It is well known that ray-tracing-based migration has severe limitations in strongly heterogeneous media and irregular acquisition geometries. Reverse time migration (RTM), on the other hand, fully accounts for the wave phenomena, including multiple arrives and turning rays due to complex velocity structure. It has the capability to fully reconstruct the image detectable in its acquisition aperture. The RTM algorithms typically require a rather accurate velocity model and demand high computing powers, and may not be applicable to real-time imaging as normally required in day-to-day medical operations. However, with the improvement of computing technology, such a computational bottleneck may not present a challenge in the near future. The present-day (RTM) algorithms are typically implemented from a flat datum for the seismic industry. It can be modified to accommodate any acquisition geometry and aperture, as long as sufficient illumination is provided. Such flexibility of RTM can be conveniently implemented for the application in USCT imaging if the spatial coordinates of the transmitters and receivers are known and enough data is collected to provide full illumination. This paper proposes an implementation of a full 3D RTM algorithm for USCT imaging to produce an accurate 3D acoustic image based on the Phase-shift-plus-interpolation (PSPI) method for wavefield extrapolation. In this method, each acquired data set (shot) is propagated back in time, and a known ultrasound wavelet is propagated forward in time, with PSPI wavefield extrapolation and a piece-wise constant velocity model of the organ (breast). The imaging condition is then applied to produce a partial image. Although each image is subject to the limitation of its own illumination aperture, the stack of multiple partial images will produce a full image of the organ, with a much-reduced noise level if compared with individual partial images.

Keywords: illumination, reverse time migration (RTM), ultrasound computed tomography (USCT), wavefield extrapolation

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