Search results for: solar power plant
710 Analysis of the Operating Load of Gas Bearings in the Gas Generator of the Turbine Engine during a Deceleration to Dash Maneuver
Authors: Zbigniew Czyz, Pawel Magryta, Mateusz Paszko
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The paper discusses the status of loads acting on the drive unit of the unmanned helicopter during deceleration to dash maneuver. Special attention was given for the loads of bearings in the gas generator turbine engine, in which will be equipped a helicopter. The analysis was based on the speed changes as a function of time for manned flight of helicopter PZL W3-Falcon. The dependence of speed change during the flight was approximated by the least squares method and then determined for its changes in acceleration. This enabled us to specify the forces acting on the bearing of the gas generator in static and dynamic conditions. Deceleration to dash maneuvers occurs in steady flight at a speed of 222 km/h by horizontal braking and acceleration. When the speed reaches 92 km/h, it dynamically changes an inclination of the helicopter to the maximum acceleration and power to almost maximum and holds it until it reaches its initial speed. This type of maneuvers are used due to ineffective shots at significant cruising speeds. It is, therefore, important to reduce speed to the optimum as soon as possible and after giving a shot to return to the initial speed (cruising). In deceleration to dash maneuvers, we have to deal with the force of gravity of the rotor assembly, gas aerodynamics forces and the forces caused by axial acceleration during this maneuver. While we can assume that the working components of the gas generator are designed so that axial gas forces they create could balance the aerodynamic effects, the remaining ones operate with a value that results from the motion profile of the aircraft. Based on the analysis, we can make a compilation of the results. For this maneuver, the force of gravity (referring to statistical calculations) respectively equals for bearing A = 5.638 N and bearing B = 1.631 N. As overload coefficient k in this direction is 1, this force results solely from the weight of the rotor assembly. For this maneuver, the acceleration in the longitudinal direction achieved value a_max = 4.36 m/s2. Overload coefficient k is, therefore, 0.44. When we multiply overload coefficient k by the weight of all gas generator components that act on the axial bearing, the force caused by axial acceleration during deceleration to dash maneuver equals only 3.15 N. The results of the calculations are compared with other maneuvers such as acceleration and deceleration and jump up and jump down maneuvers. This work has been financed by the Polish Ministry of Science and Higher Education.Keywords: gas bearings, helicopters, helicopter maneuvers, turbine engines
Procedia PDF Downloads 339709 A Factor-Analytical Approach on Identities in Environmentally Significant Behavior
Authors: Alina M. Udall, Judith de Groot, Simon de Jong, Avi Shankar
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There are many ways in which environmentally significant behavior can be explained. Dominant psychological theories, namely, the theory of planned behavior, the norm-activation theory, its extension, the value-belief-norm theory, and the theory of habit do not explain large parts of environmentally significant behaviors. A new and rapidly growing approach is to focus on how consumer’s identities predict environmentally significant behavior. Identity may be relevant because consumers have many identities that are assumed to guide their behavior. Therefore, we assume that many identities will guide environmentally significant behavior. Many identities can be relevant for environmentally significant behavior. In reviewing the literature, over 200 identities have been studied making it difficult to establish the key identities for explaining environmentally significant behavior. Therefore, this paper first aims to establish the key identities previously used for explaining environmentally significant behavior. Second, the aim is to test which key identities explain environmentally significant behavior. To address the aims, an online survey study (n = 578) is conducted. First, the exploratory factor analysis reveals 15 identity factors. The identity factors are namely, environmentally concerned identity, anti-environmental self-identity, environmental place identity, connectedness with nature identity, green space visitor identity, active ethical identity, carbon off-setter identity, thoughtful self-identity, close community identity, anti-carbon off-setter identity, environmental group member identity, national identity, identification with developed countries, cyclist identity, and thoughtful organisation identity. Furthermore, to help researchers understand and operationalize the identities, the article provides theoretical definitions for each of the identities, in line with identity theory, social identity theory, and place identity theory. Second, the hierarchical regression shows only 10 factors significantly uniquely explain the variance in environmentally significant behavior. In order of predictive power the identities are namely, environmentally concerned identity, anti-environmental self-identity, thoughtful self-identity, environmental group member identity, anti-carbon off-setter identity, carbon off-setter identity, connectedness with nature identity, national identity, and green space visitor identity. The identities explain over 60% of the variance in environmentally significant behavior, a large effect size. Based on this finding, the article reveals a new, theoretical framework showing the key identities explaining environmentally significant behavior, to help improve and align the field.Keywords: environmentally significant behavior, factor analysis, place identity, social identity
Procedia PDF Downloads 451708 Poetics of Labor: A Study of Selected Contemporary Australian Aboriginal and Immigrant Poets
Authors: Nabeel Mohammed Ali
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Background and significance of the study: This study focuses on the experiences, perspectives, and issues of the working-class Aboriginals and immigrants in Australia. In addition to dealing with their lives, struggles, and aspirations of working-class people, poetry of labor presents an insight into a neglected literary writing that goes beyond the social discourse of class distinction. In this contemporary context, it explores a broader spectrum of challenges and experiences, such as the complexities of modern labor, immigration, indigenous rights, social justice, multiculturalism, economic inequality, advocating for workers' rights and labor movements, the impact of globalization on local industries, and the evolution of labor in the digital age. Aims of the Study: The study will try to answer the following questions: What insights does poetics of labor provide to affect the literary creation of poetry at the time, as well as whether it can create a change in the social fabric of Australian diversity? What are the main themes and issues that Aboriginal and immigrant poets address in their works? How do they reflect the realities and challenges of working-class people in Australia? How do they use language, form, and style to convey their messages and emotions? How do the poets engage with and critique the dominant narratives and ideologies of Australian society and culture? How do they challenge or resist the stereotypes, prejudices, and discrimination that they face? And how do they show solidarity or empathy with others who share similar struggles or aspirations? Methodology: The study will utilize traditional Marxist paradigms to analyze the poetry of the selected poets in the context of the evolving sociopolitical landscape of the 21st century. The Neo-Marxist literary criticism is used as a theoretical tool to analyze the texts. The concept of Power dynamics to analyze the intersectionality of race, labor and class. Findings: The poetry of contemporary Australian Aboriginal and immigrant poets labor, represents a critical, yet under-explored, discussion of the intersection of labor, class, and a multicultural identity. The study will deal with the poetry of the Aboriginal poet Ali Cobby Eckermann (1963- ) and the immigrant Chinese poet Ouyang Yu ( 1955- ).Keywords: aboriginals, immigrants, Australia, working-class, Ali eckermann, ouyang Yu
Procedia PDF Downloads 35707 Shaped Crystal Growth of Fe-Ga and Fe-Al Alloy Plates by the Micro Pulling down Method
Authors: Kei Kamada, Rikito Murakami, Masahiko Ito, Mototaka Arakawa, Yasuhiro Shoji, Toshiyuki Ueno, Masao Yoshino, Akihiro Yamaji, Shunsuke Kurosawa, Yuui Yokota, Yuji Ohashi, Akira Yoshikawa
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Techniques of energy harvesting y have been widely developed in recent years, due to high demand on the power supply for ‘Internet of things’ devices such as wireless sensor nodes. In these applications, conversion technique of mechanical vibration energy into electrical energy using magnetostrictive materials n have been brought to attention. Among the magnetostrictive materials, Fe-Ga and Fe-Al alloys are attractive materials due to the figure of merits such price, mechanical strength, high magnetostrictive constant. Up to now, bulk crystals of these alloys are produced by the Bridgman–Stockbarger method or the Czochralski method. Using these method big bulk crystal up to 2~3 inch diameter can be grown. However, non-uniformity of chemical composition along to the crystal growth direction cannot be avoid, which results in non-uniformity of magnetostriction constant and reduction of the production yield. The micro-pulling down (μ-PD) method has been developed as a shaped crystal growth technique. Our group have reported shaped crystal growth of oxide, fluoride single crystals with different shape such rod, plate tube, thin fiber, etc. Advantages of this method is low segregation due to high growth rate and small diffusion of melt at the solid-liquid interface, and small kerf loss due to near net shape crystal. In this presentation, we report the shaped long plate crystal growth of Fe-Ga and Fe-Al alloys using the μ-PD method. Alloy crystals were grown by the μ-PD method using calcium oxide crucible and induction heating system under the nitrogen atmosphere. The bottom hole of crucibles was 5 x 1mm² size. A <100> oriented iron-based alloy was used as a seed crystal. 5 x 1 x 320 mm³ alloy crystal plates were successfully grown. The results of crystal growth, chemical composition analysis, magnetostrictive properties and a prototype vibration energy harvester are reported. Furthermore, continuous crystal growth using powder supply system will be reported to minimize the chemical composition non-uniformity along the growth direction.Keywords: crystal growth, micro-pulling-down method, Fe-Ga, Fe-Al
Procedia PDF Downloads 334706 Predicting Success and Failure in Drug Development Using Text Analysis
Authors: Zhi Hao Chow, Cian Mulligan, Jack Walsh, Antonio Garzon Vico, Dimitar Krastev
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Drug development is resource-intensive, time-consuming, and increasingly expensive with each developmental stage. The success rates of drug development are also relatively low, and the resources committed are wasted with each failed candidate. As such, a reliable method of predicting the success of drug development is in demand. The hypothesis was that some examples of failed drug candidates are pushed through developmental pipelines based on false confidence and may possess common linguistic features identifiable through sentiment analysis. Here, the concept of using text analysis to discover such features in research publications and investor reports as predictors of success was explored. R studios were used to perform text mining and lexicon-based sentiment analysis to identify affective phrases and determine their frequency in each document, then using SPSS to determine the relationship between our defined variables and the accuracy of predicting outcomes. A total of 161 publications were collected and categorised into 4 groups: (i) Cancer treatment, (ii) Neurodegenerative disease treatment, (iii) Vaccines, and (iv) Others (containing all other drugs that do not fit into the 3 categories). Text analysis was then performed on each document using 2 separate datasets (BING and AFINN) in R within the category of drugs to determine the frequency of positive or negative phrases in each document. A relative positivity and negativity value were then calculated by dividing the frequency of phrases with the word count of each document. Regression analysis was then performed with SPSS statistical software on each dataset (values from using BING or AFINN dataset during text analysis) using a random selection of 61 documents to construct a model. The remaining documents were then used to determine the predictive power of the models. Model constructed from BING predicts the outcome of drug performance in clinical trials with an overall percentage of 65.3%. AFINN model had a lower accuracy at predicting outcomes compared to the BING model at 62.5% but was not effective at predicting the failure of drugs in clinical trials. Overall, the study did not show significant efficacy of the model at predicting outcomes of drugs in development. Many improvements may need to be made to later iterations of the model to sufficiently increase the accuracy.Keywords: data analysis, drug development, sentiment analysis, text-mining
Procedia PDF Downloads 157705 Re-Victimization of Sex Trafficking Victims in Canada: Literature Review
Authors: Adrianna D. Hendricks
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This paper examines the factors that contribute to the re-traumatization of victims of sex trafficking within the Canadian context. Sex trafficking occurring domestically in Canada is severely under-researched, stigmatized, and under-prosecuted, leading to the re-traumatization of victims by various levels of government. This is in part due to the Canadian criminal justice system unethically utilizing prostitution laws in cases of sex trafficking and partially due to the unaddressed stigmatization victims face within the justice system itself. Utilizing evidence from a current literature review, personal correspondence, and personal life experiences, this paper will demonstrate the need for victim involvement in policy reform. The current literature review was done through an academic database search using the terms: “Sex Trafficking, Exploitation, Canada”, with the limitation of articles written within the last 5 years and written within the Canadian context. Overall, from the results, only eight articles precisely matched the criteria. The current literature argues strongly and unanimously for more research and education of professionals who have close contact with high-risk populations (doctors, police officers, social workers, etc.) to protect both minors and adults from being sexually trafficked. Additionally, for women and girls who do not have Canadian citizenship, the fear of deportation becomes a barrier to disclosing exploitation experiences to professionals. There is a desperate need for more research done in tandem with survivors and victims to inform policymaking in a meaningful way. The researcher is a survivor of sex trafficking both as a youth and as an adult, giving the researcher a unique insight into the realities of the criminal justice system for victims of sex trafficking. There is a clear need for professionals in positions of power to be re-educated about the realities of sex-trafficking, and what it means for the victims. Congruent to the current research the author calls for: standardized professional training for people in healthcare, police officers, court officials, and victim services; with the additional layers of victim involvement in creation of professional education training, and victim involvement in research. Justice for victims/survivors can only be obtained if they have been consulted and believed. Without meaningful consultation with survivors, victims who are both minors and adults will continue to fall through the cracks in policy.Keywords: Canadian policy, re-traumatization, sex-trafficking, stigmatization
Procedia PDF Downloads 66704 Split Health System for Diabetes Care in Urban Area: Experience from an Action Research Project in an Urban Poor Neighborhood in Bengaluru
Authors: T. S. Beerenahally, S. Amruthavalli, C. M. Munegowda, Leelavathi, Nagarathna
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Introduction: In majority of urban India, the health system is split between different authorities being responsible for the health care of urban population. We believe that, apart from poor awareness and financial barriers to care, there are other health system barriers which affect quality and access to care for people with diabetes. In this paper, we attempted to identify health system complexity that determines access to public health system for diabetes care in KG Halli, a poor urban neighborhood in Bengaluru. The KG Halli has been a locus of a health systems research from 2009 to 2015. Methodology: The source of data is from the observational field-notes written by research team as part of urban health action research project (UHARP). Field notes included data from the community and the public primary care center. The data was generated by the community health assistants and the other research team members during regular home visits and interaction with individuals who self-reported to be diabetic over four years as part of UHARP. Results: It emerged during data analysis that the patients were not keen on utilizing primary public health center for many reasons. Patient has felt that the service provided at the center was not integrated. There was lack of availability of medicines, with a regular stock out of medicines in a year and laboratory service for investigation was limited. Many of them said that the time given by the providers was not sufficient and there was also a feeling of providers not listening to them attentively. The power dynamics played a huge role in communication. Only the consultation was available for free of cost at the public primary care center. The patient had to spend for the investigations and the major portion for medicine. Conclusion: Diabetes is a chronic disease that poses an important emerging public health concern. Most of the financial burden is borne by the family as the public facilities have failed to provide free care in India. Our study indicated various factors including individual beliefs, stigma and financial constraints affecting compliance to diabetes care.Keywords: diabetes care, disintegrated health system, quality of care, urban health
Procedia PDF Downloads 160703 Experimental Evaluation of Contact Interface Stiffness and Damping to Sustain Transients and Resonances
Authors: Krystof Kryniski, Asa Kassman Rudolphi, Su Zhao, Per Lindholm
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ABB offers range of turbochargers from 500 kW to 80+ MW diesel and gas engines. Those operate on ships, power stations, generator-sets, diesel locomotives and large, off-highway vehicles. The units need to sustain harsh operating conditions, exposure to high speeds, temperatures and varying loads. They are expected to work at over-critical speeds damping effectively any transients and encountered resonances. Components are often connected via friction joints. Designs of those interfaces need to account for surface roughness, texture, pre-stress, etc. to sustain against fretting fatigue. The experience from field contributed with valuable input on components performance in hash sea environment and their exposure to high temperature, speed and load conditions. Study of tribological interactions of oxide formations provided an insight into dynamic activities occurring between the surfaces. Oxidation was recognized as the dominant factor of a wear. Microscopic inspections of fatigue cracks on turbine indicated insufficient damping and unrestrained structural stress leading to catastrophic failure, if not prevented in time. The contact interface exhibits strongly non-linear mechanism and to describe it the piecewise approach was used. Set of samples representing the combinations of materials, texture, surface and heat treatment were tested on a friction rig under range of loads, frequencies and excitation amplitudes. Developed numerical technique extracted the friction coefficient, tangential contact stiffness and damping. Vast amount of experimental data was processed with the multi-harmonics balance (MHB) method to categorize the components subjected to the periodic excitations. At the pre-defined excitation level both force and displacement formed semi-elliptical hysteresis curves having the same area and secant as the actual ones. By cross-correlating the terms remaining in the phase and out of the phase, respectively it was possible to separate an elastic energy from dissipation and derive the stiffness and damping characteristics.Keywords: contact interface, fatigue, rotor-dynamics, torsional resonances
Procedia PDF Downloads 375702 Feasibility Study and Energy Conversion Evaluation of Agricultural Waste Gasification in the Pomelo Garden, Taiwan
Authors: Yi-Hao Pai, Wen-Feng Chen
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The planting area of Pomelo in Hualien, Taiwan amounts to thousands of hectares. Especially in the blooming season of Pomelo, it is an important producing area for Pomelo honey, and it is also a good test field for promoting the "Under-forest Economy". However, in the current Pomelo garden planting and management operations, the large amount of agricultural waste generated by the pruning of the branches causes environmental sanitation concerns, which can lead to the hiding of pests or the infection of the Pomelo tree, and indirectly increase the health risks of bees. Therefore, how to deal with the pruning of the branches and avoid open burning is a topic of social concern in recent years. In this research, afeasibility study evaluating energy conversion efficiency through agricultural waste gasification from the Pomelo garden, Taiwan, is demonstrated. we used a high-temperature gasifier to convert the pruning of the branches into syngas and biochar. In terms of syngas composition and calorific value assessment, we use the biogas monitoring system for analysis. Then, we used Raman spectroscopy and electron microscopy (EM) to diagnose the microstructure and surface morphology of biochar. The results indicate that the 1 ton of pruning of the branches can produce 1797.03m3 of syngas, corresponding to a calorific value of 9.1MJ/m3. The main components of the gas include CH4, H2, CO, and CO2, and the corresponding gas composition ratio is 16.8%, 7.1%, 13.7%, and 24.5%. Through the biomass syngas generator with a conversion efficiency of 30% for power generation, a total of 1,358kWh can be obtained per ton of pruning of the branches. In the research of biochar, its main characteristics in Raman spectroscopy are G bands and D bands. The first-order G and D bands are at 1580 and 1350 cm⁻¹, respectively. The G bands originates from the in-plane tangential stretching of the C−C bonds in the graphitic structure, and theD band corresponds to scattering from local defects or disorders present in carbon. The area ratio of D and G peaks (D/G) increases with the decrease of reaction temperature. The larger the D/G, the higher the defect concentration and the higher the porosity. This result is consistent with the microstructure displayed by SEM. The study is expected to be able to reuse agricultural waste and promote the development of agricultural and green energy circular economy.Keywords: agricultural waste, gasification, energy conversion, pomelo garden
Procedia PDF Downloads 142701 Stretchable and Flexible Thermoelectric Polymer Composites for Self-Powered Volatile Organic Compound Vapors Detection
Authors: Petr Slobodian, Pavel Riha, Jiri Matyas, Robert Olejnik, Nuri Karakurt
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Thermoelectric devices generate an electrical current when there is a temperature gradient between the hot and cold junctions of two dissimilar conductive materials typically n-type and p-type semiconductors. Consequently, also the polymeric semiconductors composed of polymeric matrix filled by different forms of carbon nanotubes with proper structural hierarchy can have thermoelectric properties which temperature difference transfer into electricity. In spite of lower thermoelectric efficiency of polymeric thermoelectrics in terms of the figure of merit, the properties as stretchability, flexibility, lightweight, low thermal conductivity, easy processing, and low manufacturing cost are advantages in many technological and ecological applications. Polyethylene-octene copolymer based highly elastic composites filled with multi-walled carbon nanotubes (MWCTs) were prepared by sonication of nanotube dispersion in a copolymer solution followed by their precipitation pouring into non-solvent. The electronic properties of MWCNTs were moderated by different treatment techniques such as chemical oxidation, decoration by Ag clusters or addition of low molecular dopants. In this concept, for example, the amounts of oxygenated functional groups attached on MWCNT surface by HNO₃ oxidation increase p-type charge carriers. p-type of charge carriers can be further increased by doping with molecules of triphenylphosphine. For partial altering p-type MWCNTs into less p-type ones, Ag nanoparticles were deposited on MWCNT surface and then doped with 7,7,8,8-tetracyanoquino-dimethane. Both types of MWCNTs with the highest difference in generated thermoelectric power were combined to manufacture polymeric based thermoelectric module generating thermoelectric voltage when the temperature difference is applied between hot and cold ends of the module. Moreover, it was found that the generated voltage by the thermoelectric module at constant temperature gradient was significantly affected when exposed to vapors of different volatile organic compounds representing then a self-powered thermoelectric sensor for chemical vapor detection.Keywords: carbon nanotubes, polymer composites, thermoelectric materials, self-powered gas sensor
Procedia PDF Downloads 153700 Hybrid Strategies of Crisis Intervention for Sexualized Violence Using Digital Media
Authors: Katharina Kargel, Frederic Vobbe
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Sexualized violence against children and adolescents using digital media poses particular challenges for practitioners with a focus on crisis intervention (social work, psychotherapy, law enforcement). The technical delimitation of violence increases the burden on those affected and increases the complexity of interdisciplinary cooperation. Urgently needed recommendations for practical action do not yet exist in Germany. Funded by the Federal Ministry of Education and Research, these recommendations for action are being developed in the HUMAN project together with science and practice. The presentation introduces the participatory approach of the HUMAN project. We discuss the application-oriented, casuistic approach of the project and present its results using the example of concrete case-based recommendations for Action. The participants will be presented with concrete prototypical case studies from the project, which will be used to illustrate quality criteria for crisis intervention in cases of sexualized violence using digital media. On the basis of case analyses, focus group interviews and interviews with victims of violence, we present the six central challenges of sexualized violence with the use of digital media, namely: • Diffusion (Ambiguities regarding the extent and significance of violence) , • Transcendence (Space and time independence of the dynamics of violence, omnipresence), • omnipresent anxiety (considering diffusion and transcendence), • being haunted (repeated confrontation with digital memories of violence or the perpetrator), • disparity (conflicts of interpretative power between those affected and the social environment) • simultaneity (of all other factors). We point out generalizable principles with which these challenges can be dealt with professionally. Dealing professionally with sexualized violence using digital media requires a stronger networking of professional actors. A clear distinction must be made between their own mission and the mission of the network partners. Those affected by violence must be shown options for crisis intervention in the context of the aid networks. The different competencies and the professional mission of the offers of help are to be made transparent. The necessity of technical possibilities for deleting abuse images beyond criminal prosecution will be discussed. Those affected are stabilized by multimodal strategies such as a combination of rational emotive therapy, legal support and technical assistance.Keywords: sexualized violence, intervention, digital media, children and youth
Procedia PDF Downloads 233699 Discrepant Views of Social Competence and Links with Social Phobia
Authors: Pamela-Zoe Topalli, Niina Junttila, Päivi M. Niemi, Klaus Ranta
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Adolescents’ biased perceptions about their social competence (SC), whether negatively or positively, serve to influence their socioemotional adjustment such as early feelings of social phobia (nowadays referred to as Social Anxiety Disorder-SAD). Despite the importance of biased self-perceptions in adolescents’ psychosocial adjustment, the extent to which discrepancies between self- and others’ evaluations of one’s SC are linked to social phobic symptoms remains unclear in the literature. This study examined the perceptual discrepancy profiles between self- and peers’ as well as between self- and teachers’ evaluations of adolescents’ SC and the interrelations of these profiles with self-reported social phobic symptoms. The participants were 390 3rd graders (15 years old) of Finnish lower secondary school (50.8% boys, 49.2% girls). In contrast with variable-centered approaches that have mainly been used by previous studies when focusing on this subject, this study used latent profile analysis (LPA), a person-centered approach which can provide information regarding risk profiles by capturing the heterogeneity within a population and classifying individuals into groups. LPA revealed the following five classes of discrepancy profiles: i) extremely negatively biased perceptions of SC, ii) negatively biased perceptions of SC, iii) quite realistic perceptions of SC, iv) positively biased perceptions of SC, and v) extremely positively biased perceptions of SC. Adolescents with extremely negatively biased perceptions and negatively biased perceptions of their own SC reported the highest number of social phobic symptoms. Adolescents with quite realistic, positively biased and extremely positively biased perceptions reported the lowest number of socio-phobic symptoms. The results point out the negatively and the extremely negatively biased perceptions as possible contributors to social phobic symptoms. Moreover, the association of quite realistic perceptions with low number of social phobic symptoms indicates its potential protective power against social phobia. Finally, positively and extremely positively biased perceptions of SC are negatively associated with social phobic symptoms in this study. However, the profile of extremely positively biased perceptions might be linked as well with the existence of externalizing problems such as antisocial behavior (e.g. disruptive impulsivity). The current findings highlight the importance of considering discrepancies between self- and others’ perceptions of one’s SC in clinical and research efforts. Interventions designed to prevent or moderate social phobic symptoms need to take into account individual needs rather than aiming for uniform treatment. Implications and future directions are discussed.Keywords: adolescence, latent profile analysis, perceptual discrepancies, social competence, social phobia
Procedia PDF Downloads 246698 Zooming into the Leadership Behaviours Desired by the 21st Century Workforce: Introduction of the Research Theory and Methods
Authors: Anita Bela, Marta Juhasz
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Adapting to the always-changing environment comes with complex determinants. The authors are zooming into one aspect only when the current workforce comes with obstacles by being less keen to stay engaged, even short or mid-term, resulting in additional challenges impacting the business performance. Seeing these occurring in practice made the researchers eager to gain a better understanding of the reasons behind. The paper aims to provide an overview of the theoretical background and research methods planned for the different stages of the research. The theoretical part takes the leadership behaviors under lens while the focus is on finding ways to attract and retain those who prefer working under more flexible employment conditions (e.g. contractor, contingent worker, etc.). These are considered as the organizational values and along with the power of people management are having their engaging relevance. The organizational culture (visible or invisible level) is clearly the mirror of the set of shared values guiding all members of the companies towards acceptable behavior. The applied research method, inductive reasoning was selected since the focus and questions raised in this research are results of specific observations made on the employees (various employment types) and leaders of start-ups and corporates. By comparing the similarities and differences, the researchers are hoping to prove the readiness and agility of the start-up culture for the desired leadership behaviours of the current and future workforce against the corporate culture. While exploring the preferences and engaging factors of the 21st-century workforce the data gathering would happen through website analysis – using ATLAS.ti qualitative software – followed by interview sessions where demographics will be collected and preferred leadership behaviors - using the Critical Incident Technique. Moreover, a short engagement survey will be administered to understand the linkage between the organizational culture type and engagement level. To conclude, after gaining theoretical understanding, we will zoom back to the employees to reveal the behaviors to be followed to achieve engagement in an environment where nothing is stable and where the companies always must keep their agile eyes and reactions vivid.Keywords: leadership behaviours, organizational culture, qualitative analysis, workforce engagement
Procedia PDF Downloads 116697 The Boy Who Cried Wolf-North Korea Nuclear Test and Its Implication to the Regional Stability
Authors: Mark Wenyi Lai
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The very lethal weapon of nuclear warhead had threatened the survival of the world for half of the 20th century. When most of the countries have already denounced and stopped the development, one country is eager to produce and use them. Since 2006, Pyongyang has launched six times of nuclear tests. The most recent one in September 2017 signaled North Korea’s military capability to project the mass destruction through ICBM (Intercontinental Ballistic Missile) over Seoul, Tokyo, Guam, Hawaii, Alaska or probably the West Coast of the United States with the explosive energy ten times of the atom bombing of Hiroshima in 1945. This research paper adopted time-series content analysis focusing on the related countries responses to North Korea’s tests in 2006, 2009, 2013, and 2016. The preliminary hypotheses are first, North Korea determined to protect the regime by having triad nuclear capability. Negotiations are mere means to this end. Second, South Korea is paralyzed by its ineffective domestic politics and unable to develop its independent strategy toward the North. Third, Japan was using the external threat to campaign for its rearmament plan and brought instability in foreign relations. Fourth, China found herself in the strange position of defending the loyal buffer state meanwhile witnessing the fourth and dangerous neighboring country gaining the card into nuclear club. Fifth, the United States had admitted that North Korea’s going nuclear is unstoppable. Therefore, to keep the regional stability in the East Asia, the US relied on the new balance of power formed by everyone versus Pyongyang. But, countries in East Asia actually have problems getting along with each other. Sixth, Russia distanced herself from the North Kore row but benefitted by advancing its strategic importance in the Far East. Tracing back the history of nuclear states, this research paper concluded that North Korea will head on becoming a more confident country. The regional stability will restore once related countries deal with the new fact and treat Pyongyang regime with a new strategy. The gradual opening and economic reform are on the way for the North Korea in the near future.Keywords: nuclear test, North Korea, six party talk, US foreign policy
Procedia PDF Downloads 280696 Magnetic Lines of Force and Diamagnetism
Authors: Angel Pérez Sánchez
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Magnet attraction or repulsion is not a product of a strange force from afar but comes from anchored lines of force inside the magnet as if it were reinforced concrete since you can move a small block by taking the steel rods that protrude from its interior. This approach serves as a basis for studying the behavior of diamagnetic materials. The significance of this study is to unify all diamagnetic phenomena: Movement of grapes, cooper approaching a magnet, Magnet levitation, etc., with a single explanation for all these phenomena. The method followed has consisted of observation of hundreds of diamagnetism experiments (in copper, aluminum, grapes, tomatoes, and bismuth), including the creation of own and new experiments and application of logical deduction product of these observations. Approaching a magnet to a hanging grape, Diamagnetism seems to consist not only of a slight repulsion but also of a slight attraction at a small distance. Replacing the grapes with a copper sphere, it behaves like the grape, pushing and pulling a nearby magnet. Diamagnetism could be redefined in the following way: There are materials that don't magnetize their internal structure when approaching a magnet, as ferromagnetic materials do. But they do allow magnetic lines of force to run through its interior, enhancing them without creating their own lines of force. Magnet levitates on superconducting ceramics because magnet gives lines near poles a force superior to what a superconductor can enhance these lines. Little further from the magnet, enhancing of lines by the superconductor is greater than the strength provided by the magnet due to the distance from the magnet's pole. It is this point that defines the magnet's levitation band. The anchoring effect of lines is what ultimately keeps the magnet and superconductor at a certain distance. The magnet seeks to levitate the area in which magnetic lines are stronger near de magnet's poles. Pouring ferrofluid into a magnet, lines of force are observed coming out of the poles. On other occasions, diamagnetic materials simply enhance the lines they receive without moving their position since their own weight is greater than the strength of the enhanced lines. (This is the case with grapes and copper). Magnet and diamagnetic materials look for a place where the lines of force are most enhanced, and this is at a small distance. Once the ideal distance is established, they tend to keep it by pushing or pulling on each other. At a certain distance from the magnet: the power exerted by diamagnetic materials is greater than the force of lines in the vicinity of the magnet's poles. All Diamagnetism phenomena: copper, aluminum, grapes, tomatoes, bismuth levitation, and magnet levitation on superconducting ceramics can now be explained with the support of magnetic lines of force.Keywords: diamagnetism, magnetic levitation, magnetic lines of force, enhancing magnetic lines
Procedia PDF Downloads 88695 Salicornia bigelovii, a Promising Halophyte for Biosaline Agriculture: Lessons Learned from a 4-Year Field Study in United Arab Emirates
Authors: Dionyssia Lyra, Shoaib Ismail
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Salinization of natural resources constitutes a significant component of the degradation force that leads to depletion of productive lands and fresh water reserves. The global extent of salt-affected soils is approximately 7% of the earth’s land surface and is expanding. The problems of excessive salt accumulation are most widespread in coastal, arid and semi-arid regions, where agricultural production is substantially hindered. The use of crops that can withstand high saline conditions is extremely interesting in such a context. Salt-loving plants or else ‘halophytes’ thrive when grown in hostile saline conditions, where traditional crops cannot survive. Salicornia bigelovii, a halophytic crop with multiple uses (vegetable, forage, biofuel), has demonstrated remarkable adaptability to harsh climatic conditions prevailing in dry areas with great potential for its expansion. Since 2011, the International Center for Biosaline Agriculture (ICBA) with Masdar Institute (MI) and King Abdul Aziz University of Science & Technology (KAUST) to look into the potential for growing S. bigelovii under hot and dry conditions. Through the projects undertaken, 50 different S. bigelovii genotypes were assessed under high saline conditions. The overall goal was to select the best performing S. bigelovii populations in terms of seed and biomass production for future breeding. Specific objectives included: 1) evaluation of selected S. bigelovii genotypes for various agronomic and growth parameters under field conditions, 2) seed multiplication of S. bigelovii using saline groundwater and 3) acquisition of inbred lines for further breeding. Field trials were conducted for four consecutive years at ICBA headquarters. During the first year, one Salicornia population was evaluated for seed and biomass production at different salinity levels, fertilizer treatments and planting methods. All growth parameters and biomass productivity for the salicornia population showed better performance with optimal biomass production in terms of both salinity level and fertilizer application. During the second year, 46 Salicornia populations (obtained from KAUST and Masdar Institute) were evaluated for 24 growth parameters and treated with groundwater through drip irrigation. The plant material originated from wild collections. Six populations were also assessed for their growth performance under full-strength seawater. Salicornia populations were highly variable for all characteristics under study for both irrigation treatments, indicating that there is a large pool of genetic information available for breeding. Irrigation with the highest level of salinity had a negative impact on the agronomic performance. The maximum seed yield obtained was 2 t/ha at 20 dS/m (groundwater treatment) at 25 cm x 25 cm planting distance. The best performing Salicornia populations for fresh biomass and seed yield were selected for the following season. After continuous selection, the best performing salicornia will be adopted for scaling-up options. Taking into account the results of the production field trials, salicornia expansion will be targeted in coastal areas of the Arabian Peninsula. As a crop with high biofuel and forage potential, its cultivation can improve the livelihood of local farmers.Keywords: biosaline agriculture, genotypes selection, halophytes, Salicornia bigelovii
Procedia PDF Downloads 407694 From Theory to Practice: Harnessing Mathematical and Statistical Sciences in Data Analytics
Authors: Zahid Ullah, Atlas Khan
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The rapid growth of data in diverse domains has created an urgent need for effective utilization of mathematical and statistical sciences in data analytics. This abstract explores the journey from theory to practice, emphasizing the importance of harnessing mathematical and statistical innovations to unlock the full potential of data analytics. Drawing on a comprehensive review of existing literature and research, this study investigates the fundamental theories and principles underpinning mathematical and statistical sciences in the context of data analytics. It delves into key mathematical concepts such as optimization, probability theory, statistical modeling, and machine learning algorithms, highlighting their significance in analyzing and extracting insights from complex datasets. Moreover, this abstract sheds light on the practical applications of mathematical and statistical sciences in real-world data analytics scenarios. Through case studies and examples, it showcases how mathematical and statistical innovations are being applied to tackle challenges in various fields such as finance, healthcare, marketing, and social sciences. These applications demonstrate the transformative power of mathematical and statistical sciences in data-driven decision-making. The abstract also emphasizes the importance of interdisciplinary collaboration, as it recognizes the synergy between mathematical and statistical sciences and other domains such as computer science, information technology, and domain-specific knowledge. Collaborative efforts enable the development of innovative methodologies and tools that bridge the gap between theory and practice, ultimately enhancing the effectiveness of data analytics. Furthermore, ethical considerations surrounding data analytics, including privacy, bias, and fairness, are addressed within the abstract. It underscores the need for responsible and transparent practices in data analytics, and highlights the role of mathematical and statistical sciences in ensuring ethical data handling and analysis. In conclusion, this abstract highlights the journey from theory to practice in harnessing mathematical and statistical sciences in data analytics. It showcases the practical applications of these sciences, the importance of interdisciplinary collaboration, and the need for ethical considerations. By bridging the gap between theory and practice, mathematical and statistical sciences contribute to unlocking the full potential of data analytics, empowering organizations and decision-makers with valuable insights for informed decision-making.Keywords: data analytics, mathematical sciences, optimization, machine learning, interdisciplinary collaboration, practical applications
Procedia PDF Downloads 93693 Climate Changes Impact on Artificial Wetlands
Authors: Carla Idely Palencia-Aguilar
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Artificial wetlands play an important role at Guasca Municipality in Colombia, not only because they are used for the agroindustry, but also because more than 45 species were found, some of which are endemic and migratory birds. Remote sensing was used to determine the changes in the area occupied by water of artificial wetlands by means of Aster and Modis images for different time periods. Evapotranspiration was also determined by three methods: Surface Energy Balance System-Su (SEBS) algorithm, Surface Energy Balance- Bastiaanssen (SEBAL) algorithm, and Potential Evapotranspiration- FAO. Empirical equations were also developed to determine the relationship between Normalized Difference Vegetation Index (NDVI) versus net radiation, ambient temperature and rain with an obtained R2 of 0.83. Groundwater level fluctuations on a daily basis were studied as well. Data from a piezometer placed next to the wetland were fitted with rain changes (with two weather stations located at the proximities of the wetlands) by means of multiple regression and time series analysis, the R2 from the calculated and measured values resulted was higher than 0.98. Information from nearby weather stations provided information for ordinary kriging as well as the results for the Digital Elevation Model (DEM) developed by using PCI software. Standard models (exponential, spherical, circular, gaussian, linear) to describe spatial variation were tested. Ordinary Cokriging between height and rain variables were also tested, to determine if the accuracy of the interpolation would increase. The results showed no significant differences giving the fact that the mean result of the spherical function for the rain samples after ordinary kriging was 58.06 and a standard deviation of 18.06. The cokriging using for the variable rain, a spherical function; for height variable, the power function and for the cross variable (rain and height), the spherical function had a mean of 57.58 and a standard deviation of 18.36. Threatens of eutrophication were also studied, given the unconsciousness of neighbours and government deficiency. Water quality was determined over the years; different parameters were studied to determine the chemical characteristics of water. In addition, 600 pesticides were studied by gas and liquid chromatography. Results showed that coliforms, nitrogen, phosphorous and prochloraz were the most significant contaminants.Keywords: DEM, evapotranspiration, geostatistics, NDVI
Procedia PDF Downloads 120692 Spectral Mapping of Hydrothermal Alteration Minerals for Geothermal Exploration Using Advanced Spaceborne Thermal Emission and Reflection Radiometer Short Wave Infrared Data
Authors: Aliyu J. Abubakar, Mazlan Hashim, Amin B. Pour
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Exploiting geothermal resources for either power, home heating, Spa, greenhouses, industrial or tourism requires an initial identification of suitable areas. This can be done cost-effectively using remote sensing satellite imagery which has synoptic capabilities of covering large areas in real time and by identifying possible areas of hydrothermal alteration and minerals related to Geothermal systems. Earth features and minerals are known to have unique diagnostic spectral reflectance characteristics that can be used to discriminate them. The focus of this paper is to investigate the applicability of mapping hydrothermal alteration in relation to geothermal systems (thermal springs) at Yankari Park Northeastern Nigeria, using Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) satellite data for resource exploration. The ASTER Short Wave Infrared (SWIR) bands are used to highlight and discriminate alteration areas by employing sophisticated digital image processing techniques including image transformations and spectral mapping methods. Field verifications are conducted at the Yankari Park using hand held Global Positioning System (GPS) monterra to identify locations of hydrothermal alteration and rock samples obtained at the vicinity and surrounding areas of the ‘Mawulgo’ and ‘Wikki’ thermal springs. X-Ray Diffraction (XRD) results of rock samples obtained from the field validated hydrothermal alteration by the presence of indicator minerals including; Dickite, Kaolinite, Hematite and Quart. The study indicated the applicability of mapping geothermal anomalies for resource exploration in unmapped sparsely vegetated savanna environment characterized by subtle surface manifestations such as thermal springs. The results could have implication for geothermal resource exploration especially at the prefeasibility stages by narrowing targets for comprehensive surveys and in unexplored savanna regions where expensive airborne surveys are unaffordable.Keywords: geothermal exploration, image enhancement, minerals, spectral mapping
Procedia PDF Downloads 363691 Recursion, Merge and Event Sequence: A Bio-Mathematical Perspective
Authors: Noury Bakrim
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Formalization is indeed a foundational Mathematical Linguistics as demonstrated by the pioneering works. While dialoguing with this frame, we nonetheless propone, in our approach of language as a real object, a mathematical linguistics/biosemiotics defined as a dialectical synthesis between induction and computational deduction. Therefore, relying on the parametric interaction of cycles, rules, and features giving way to a sub-hypothetic biological point of view, we first hypothesize a factorial equation as an explanatory principle within Category Mathematics of the Ergobrain: our computation proposal of Universal Grammar rules per cycle or a scalar determination (multiplying right/left columns of the determinant matrix and right/left columns of the logarithmic matrix) of the transformable matrix for rule addition/deletion and cycles within representational mapping/cycle heredity basing on the factorial example, being the logarithmic exponent or power of rule deletion/addition. It enables us to propone an extension of minimalist merge/label notions to a Language Merge (as a computing principle) within cycle recursion relying on combinatorial mapping of rules hierarchies on external Entax of the Event Sequence. Therefore, to define combinatorial maps as language merge of features and combinatorial hierarchical restrictions (governing, commanding, and other rules), we secondly hypothesize from our results feature/hierarchy exponentiation on graph representation deriving from Gromov's Symbolic Dynamics where combinatorial vertices from Fe are set to combinatorial vertices of Hie and edges from Fe to Hie such as for all combinatorial group, there are restriction maps representing different derivational levels that are subgraphs: the intersection on I defines pullbacks and deletion rules (under restriction maps) then under disjunction edges H such that for the combinatorial map P belonging to Hie exponentiation by intersection there are pullbacks and projections that are equal to restriction maps RM₁ and RM₂. The model will draw on experimental biomathematics as well as structural frames with focus on Amazigh and English (cases from phonology/micro-semantics, Syntax) shift from Structure to event (especially Amazigh formant principle resolving its morphological heterogeneity).Keywords: rule/cycle addition/deletion, bio-mathematical methodology, general merge calculation, feature exponentiation, combinatorial maps, event sequence
Procedia PDF Downloads 127690 Lock in, Lock Out: A Double Lens Analysis of Local Media Paywall Strategies and User Response
Authors: Mona Solvoll, Ragnhild Kr. Olsen
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Background and significance of the study: Newspapers are going through radical changes with increased competition, eroding readerships and declining advertising resulting in plummeting overall revenues. This has lead to a quest for new business models, focusing on monetizing content. This research paper investigates both how local online newspapers have introduced user payment and how the audience has received these changes. Given the role of local media in keeping their communities informed and those in power accountable, their potential impact on civic engagement and cultural integration in local communities, the business model innovations of local media deserves far more research interest. Empirically, the findings are interesting for local journalists, local media managers as well as local advertisers. Basic methodologies: The study is based on interviews with commercial leaders in 20 Norwegian local newspapers in addition to a national survey data from 1600 respondents among local media users. The interviews were conducted in the second half of 2015, while the survey was conducted in September 2016. Theoretically, the study draws on the business model framework. Findings: The analysis indicates that paywalls aim more at reducing digital cannibalisation of print revenue than about creating new digital income. The newspapers are mostly concerned with retaining “old” print subscribers and transform them into digital subscribers. However, this strategy may come at a high price for newspapers if their defensive print strategy drives away younger digital readership and hamper their recruitment potential for new audiences as some previous studies have indicated. Analysis of young reader news habits indicates that attracting the younger audience to traditional local news providers is particularly challenging and that they are more prone to seek alternative news sources than the older audience is. Conclusion: The paywall strategy applied by the local newspapers may be well fitted to stabilise print subscription figures and facilitate more tailored and better services for already existing customers, but far less suited for attracting new ones. The paywall is a short-sighted strategy, which drives away younger readers and paves the road for substitute offerings, particularly Facebook.Keywords: business model, newspapers, paywall, user payment
Procedia PDF Downloads 277689 Analysis and Design of Exo-Skeleton System Based on Multibody Dynamics
Authors: Jatin Gupta, Bishakh Bhattacharya
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With the aging process, many people start suffering from the problem of weak limbs resulting in mobility disorders and loss of sensory and motor function of limbs. Wearable robotic devices are viable solutions to help people suffering from these issues by augmenting their strength. These robotic devices, popularly known as exoskeletons aides user by providing external power and controlling the dynamics so as to achieve desired motion. Present work studies a simplified dynamic model of the human gait. A four link open chain kinematic model is developed to describe the dynamics of Single Support Phase (SSP) of the human gait cycle. The dynamic model is developed integrating mathematical models of the motion of inverted and triple pendulums. Stance leg is modeled as inverted pendulum having single degree of freedom and swing leg as triple pendulum having three degrees of freedom viz. thigh, knee, and ankle joints. The kinematic model is formulated using forward kinematics approach. Lagrangian approach is used to formulate governing dynamic equation of the model. For a system of nonlinear differential equations, numerical method is employed to obtain system response. Reference trajectory is generated using human body simulator, LifeMOD. For optimal mechanical design and controller design of exoskeleton system, it is imperative to study parameter sensitivity of the system. Six different parameters viz. thigh, shank, and foot masses and lengths are varied from 85% to 115% of the original value for the present work. It is observed that hip joint of swing leg is the most sensitive and ankle joint of swing leg is the least sensitive one. Changing link lengths causes more deviation in system response than link masses. Also, shank length and thigh mass are most sensitive parameters. Finally, the present study gives an insight on different factors that should be considered while designing a lower extremity exoskeleton.Keywords: lower limb exoskeleton, multibody dynamics, energy based formulation, optimal design
Procedia PDF Downloads 200688 Vibroacoustic Modulation of Wideband Vibrations and its Possible Application for Windmill Blade Diagnostics
Authors: Abdullah Alnutayfat, Alexander Sutin, Dong Liu
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Wind turbine has become one of the most popular energy productions. However, failure of blades and maintenance costs evolve into significant issues in the wind power industry, so it is essential to detect the initial blade defects to avoid the collapse of the blades and structure. This paper aims to apply modulation of high-frequency blade vibrations by low-frequency blade rotation, which is close to the known Vibro-Acoustic Modulation (VAM) method. The high-frequency wideband blade vibration is produced by the interaction of the surface blades with the environment air turbulence, and the low-frequency modulation is produced by alternating bending stress due to gravity. The low-frequency load of rotational wind turbine blades ranges between 0.2-0.4 Hz and can reach up to 2 Hz for strong wind. The main difference between this study and previous ones on VAM methods is the use of a wideband vibration signal from the blade's natural vibrations. Different features of the vibroacoustic modulation are considered using a simple model of breathing crack. This model considers the simple mechanical oscillator, where the parameters of the oscillator are varied due to low-frequency blade rotation. During the blade's operation, the internal stress caused by the weight of the blade modifies the crack's elasticity and damping. The laboratory experiment using steel samples demonstrates the possibility of VAM using a probe wideband noise signal. A cycle load with a small amplitude was used as a pump wave to damage the tested sample, and a small transducer generated a wideband probe wave. The received signal demodulation was conducted using the Detecting of Envelope Modulation on Noise (DEMON) approach. In addition, the experimental results were compared with the modulation index (MI) technique regarding the harmonic pump wave. The wideband and traditional VAM methods demonstrated similar sensitivity for earlier detection of invisible cracks. Importantly, employing a wideband probe signal with the DEMON approach speeds up and simplifies testing since it eliminates the need to conduct tests repeatedly for various harmonic probe frequencies and to adjust the probe frequency.Keywords: vibro-acoustic modulation, detecting of envelope modulation on noise, damage, turbine blades
Procedia PDF Downloads 99687 Expanded Polyurethane Foams and Waterborne-Polyurethanes from Vegetable Oils
Authors: A.Cifarelli, L. Boggioni, F. Bertini, L. Magon, M. Pitalieri, S. Losio
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Nowadays, the growing environmental awareness and the dwindling of fossil resources stimulate the polyurethane (PU) industry towards renewable polymers with low carbon footprint to replace the feed stocks from petroleum sources. The main challenge in this field consists in replacing high-performance products from fossil-fuel with novel synthetic polymers derived from 'green monomers'. The bio-polyols from plant oils have attracted significant industrial interest and major attention in scientific research due to their availability and biodegradability. Triglycerides rich in unsaturated fatty acids, such as soybean oil (SBO) and linseed oil (ELO), are particularly interesting because their structures and functionalities are tunable by chemical modification in order to obtain polymeric materials with expected final properties. Unfortunately, their use is still limited for processing or performance problems because a high functionality, as well as OH number of the polyols will result in an increase in cross-linking densities of the resulting PUs. The main aim of this study is to evaluate soy and linseed-based polyols as precursors to prepare prepolymers for the production of polyurethane foams (PUFs) or waterborne-polyurethanes (WPU) used as coatings. An effective reaction route is employed for its simplicity and economic impact. Indeed, bio-polyols were synthesized by a two-step method: epoxidation of the double bonds in vegetable oils and solvent-free ring-opening reaction of the oxirane with organic acids. No organic solvents have been used. Acids with different moieties (aliphatic or aromatics) and different length of hydrocarbon backbones can be used to customize polyols with different functionalities. The ring-opening reaction requires a fine tuning of the experimental conditions (time, temperature, molar ratio of carboxylic acid and epoxy group) to control the acidity value of end-product as well as the amount of residual starting materials. Besides, a Lewis base catalyst is used to favor the ring opening reaction of internal epoxy groups of the epoxidized oil and minimize the formation of cross-linked structures in order to achieve less viscous and more processable polyols with narrower polydispersity indices (molecular weight lower than 2000 g/mol⁻¹). The functionality of optimized polyols is tuned from 2 to 4 per molecule. The obtained polyols are characterized by means of GPC, NMR (¹H, ¹³C) and FT-IR spectroscopy to evaluate molecular masses, molecular mass distributions, microstructures and linkage pathways. Several polyurethane foams have been prepared by prepolymer method blending conventional synthetic polyols with new bio-polyols from soybean and linseed oils without using organic solvents. The compatibility of such bio-polyols with commercial polyols and diisocyanates is demonstrated. The influence of the bio-polyols on the foam morphology (cellular structure, interconnectivity), density, mechanical and thermal properties has been studied. Moreover, bio-based WPUs have been synthesized by well-established processing technology. In this synthesis, a portion of commercial polyols is substituted by the new bio-polyols and the properties of the coatings on leather substrates have been evaluated to determine coating hardness, abrasion resistance, impact resistance, gloss, chemical resistance, flammability, durability, and adhesive strength.Keywords: bio-polyols, polyurethane foams, solvent free synthesis, waterborne-polyurethanes
Procedia PDF Downloads 129686 Study on Spatial Structure and Evolvement Process of Traditional Villages’ Courtyard Based on Clannism
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The origination and development of Chinese traditional villages have a strong link with clan society. Thousands of traditional villages are constituted by one big family who have the same surname. Villages’ basic social relationships are built on the basis of family kinship. Clan power controls family courtyards’ spatial structure and influences their evolvement process. Compared with other countries, research from perspective of clanism is a particular and universally applicable manner to recognize Chinese traditional villages’ space features. This paper takes traditional villages in astern Zhejiang province as examples, especially a single-clan village named Zoumatang. Through combining rural sociology with architecture, it clarifies the coupling relationship between clan structure and village space, reveals spatial composition and evolvement logic of family courtyards. Clan society pays much attention to the patrilineal kinship and genealogy. In astern Zhejiang province, clan is usually divided to ‘clan-branches-families’ three levels. Its structural relationship looks like pyramid, which results in ‘center-margin’ structure when projecting to villages’ space. Due to the cultural tradition of ancestor worship, family courtyards’ space exist similar ‘center-margin’ structure. Ancestor hall and family temple are respectively the space core of village and courtyard. Other parts of courtyard also shows order of superiority and inferiority. Elder and men must be the first. However, along with the disintegration of clan society, family courtyard gradually appears fragmentation trend. Its spatial structure becomes more and more flexible and its scale becomes smaller and smaller. Living conditions rather than ancestor worship turn out to be primary consideration. As a result, there are different courtyard historical prototype in different historic period. To some extent, Chinese present traditional villages’ conservation ignore the impact of clan society. This paper discovers the social significance of courtyard’s spatial texture and rebuilds the connection between society and space. It is expected to promote Chinese traditional villages’ conservation paying more attention to authenticity which defined in the historical process and integrity which built on the basis of social meaning.Keywords: China, clanism, courtyard, evolvement process, spatial structure, traditional village
Procedia PDF Downloads 320685 The Effect of Air Filter Performance on Gas Turbine Operation
Authors: Iyad Al-Attar
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Air filters are widely used in gas turbines applications to ensure that the large mass (500kg/s) of clean air reach the compressor. The continuous demand of high availability and reliability has highlighted the critical role of air filter performance in providing enhanced air quality. In addition to being challenged with different environments [tropical, coastal, hot], gas turbines confront wide array of atmospheric contaminants with various concentrations and particle size distributions that would lead to performance degradation and components deterioration. Therefore, the role of air filters is of a paramount importance since fouled compressor can reduce power output and availability of the gas turbine to over 70 % throughout operation. Consequently, accurate filter performance prediction is critical tool in their selection considering their role in minimizing the economic impact of outages. In fact, actual performance of Efficient Particulate Air [EPA] filters used in gas turbine tend to deviate from the performance predicted by laboratory results. This experimental work investigates the initial pressure drop and fractional efficiency curves of full-scale pleated V-shaped EPA filters used globally in gas turbine. The investigation involved examining the effect of different operational conditions such as flow rates [500 to 5000 m3/h] and design parameters such as pleat count [28, 30, 32 and 34 pleats per 100mm]. This experimental work has highlighted the underlying reasons behind the reduction in filter permeability due to the increase of flow rates and pleat density. The reasons, which led to surface area losses of filtration media, are due to one or combination of the following effects: pleat-crowding, deflection of the entire pleated panel, pleat distortion at the corner of the pleat and/or filtration medium compression. This paper also demonstrates that the effect of increasing the flow rate has more pronounced effect on filter performance compared to pleating density. This experimental work suggests that a valid comparison of the pleat densities should be based on the effective surface area, namely, the area that participates in the filtration process, and not the total surface area the pleat density provides. Throughout this study, optimal pleat count that satisfies both initial pressure drop and efficiency requirements may not have necessarily existed.Keywords: filter efficiency, EPA Filters, pressure drop, permeability
Procedia PDF Downloads 239684 Time Fetching Water and Maternal Childcare Practices: Comparative Study of Women with Children Living in Ethiopia and Malawi
Authors: Davod Ahmadigheidari, Isabel Alvarez, Kate Sinclair, Marnie Davidson, Patrick Cortbaoui, Hugo Melgar-Quiñonez
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The burden of collecting water tends to disproportionately fall on women and girls in low-income countries. Specifically, women spend between one to eight hours per day fetching water for domestic use in Sub-Saharan Africa. While there has been research done on the global time burden for collecting water, it has been mainly focused on water quality parameters; leaving the relationship between water fetching and health outcomes understudied. There is little available evidence regarding the relationship between water fetching and maternal child care practices. The main objective of this study was to help fill the aforementioned gap in the literature. Data from two surveys in Ethiopia and Malawi conducted by CARE Canada in 2016-2017 were used. Descriptive statistics indicate that women were predominantly responsible for collecting water in both Ethiopia (87%) and Malawi (99%) respectively, with the majority spending more than 30 minutes per day on water collection. With regards to child care practices, in both countries, breastfeeding was relatively high (77% and 82%, respectively); and treatment for malnutrition was low (15% and 8%, respectively). However, the same consistency was not found for weighing; in Ethiopia only 16% took their children for weighting in contrast to 94% in Malawi. These three practices were summed to create one variable for regressions analyses. Unadjusted logistic regression findings showed that only in Ethiopia was time fetching water significantly associated with child care practices. Once adjusted for covariates, this relationship was no longer found to be significant. Adjusted logistic regressions also showed that the factors that did influence child care practices differed slightly between the two countries. In Ethiopia, a lack of access to community water supply (OR= 0.668; P=0.010), poor attitudes towards gender equality (OR= 0.608; P=0.001), no access to land and (OR=0.603; P=0.000), significantly decreased a women’s odd of using positive childcare practices. Notably, being young women between 15-24 years (OR=2.308; P=0.017), and 25-29 (OR=2.065; P=0.028) increased probability of using positive childcare practices. Whereas in Malawi, higher maternal age, low decision-making power, significantly decreased a women’s odd of using positive childcare practices. In conclusion, this study found that even though amount of time spent by women fetching water makes a difference for childcare practices, it is not significantly related to women’s child care practices when controlling the covariates. Importantly, women’s age contributes to child care practices in Ethiopia and Malawi.Keywords: time fetching water, community water supply, women’s child care practices, Ethiopia, Malawi
Procedia PDF Downloads 202683 Evaluating the Small-Strain Mechanical Properties of Cement-Treated Clayey Soils Based on the Confining Pressure
Authors: Muhammad Akmal Putera, Noriyuki Yasufuku, Adel Alowaisy, Ahmad Rifai
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Indonesia’s government has planned a project for a high-speed railway connecting the capital cities, Jakarta and Surabaya, about 700 km. Based on that location, it has been planning construction above the lowland soil region. The lowland soil region comprises cohesive soil with high water content and high compressibility index, which in fact, led to a settlement problem. Among the variety of railway track structures, the adoption of the ballastless track was used effectively to reduce the settlement; it provided a lightweight structure and minimized workspace. Contradictorily, deploying this thin layer structure above the lowland area was compensated with several problems, such as lack of bearing capacity and deflection behavior during traffic loading. It is necessary to combine with ground improvement to assure a settlement behavior on the clayey soil. Reflecting on the assurance of strength increment and working period, those were convinced by adopting methods such as cement-treated soil as the substructure of railway track. Particularly, evaluating mechanical properties in the field has been well known by using the plate load test and cone penetration test. However, observing an increment of mechanical properties has uncertainty, especially for evaluating cement-treated soil on the substructure. The current quality control of cement-treated soils was established by laboratory tests. Moreover, using small strain devices measurement in the laboratory can predict more reliable results that are identical to field measurement tests. Aims of this research are to show an intercorrelation of confining pressure with the initial condition of the Young modulus (E_o), Poisson ratio (υ_o) and Shear modulus (G_o) within small strain ranges. Furthermore, discrepancies between those parameters were also investigated. Based on the experimental result confirmed the intercorrelation between cement content and confining pressure with a power function. In addition, higher cement ratios have discrepancies, conversely with low mixing ratios.Keywords: amount of cement, elastic zone, high-speed railway, lightweight structure
Procedia PDF Downloads 141682 Experiments to Study the Vapor Bubble Dynamics in Nucleate Pool Boiling
Authors: Parul Goel, Jyeshtharaj B. Joshi, Arun K. Nayak
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Nucleate boiling is characterized by the nucleation, growth and departure of the tiny individual vapor bubbles that originate in the cavities or imperfections present in the heating surface. It finds a wide range of applications, e.g. in heat exchangers or steam generators, core cooling in power reactors or rockets, cooling of electronic circuits, owing to its highly efficient transfer of large amount of heat flux over small temperature differences. Hence, it is important to be able to predict the rate of heat transfer and the safety limit heat flux (critical heat flux, heat flux higher than this can lead to damage of the heating surface) applicable for any given system. A large number of experimental and analytical works exist in the literature, and are based on the idea that the knowledge of the bubble dynamics on the microscopic scale can lead to the understanding of the full picture of the boiling heat transfer. However, the existing data in the literature are scattered over various sets of conditions and often in disagreement with each other. The correlations obtained from such data are also limited to the range of conditions they were established for and no single correlation is applicable over a wide range of parameters. More recently, a number of researchers have been trying to remove empiricism in the heat transfer models to arrive at more phenomenological models using extensive numerical simulations; these models require state-of-the-art experimental data for a wide range of conditions, first for input and later, for their validation. With this idea in mind, experiments with sub-cooled and saturated demineralized water have been carried out under atmospheric pressure to study the bubble dynamics- growth rate, departure size and frequencies for nucleate pool boiling. A number of heating elements have been used to study the dependence of vapor bubble dynamics on the heater surface finish and heater geometry along with the experimental conditions like the degree of sub-cooling, super heat and the heat flux. An attempt has been made to compare the data obtained with the existing data and the correlations in the literature to generate an exhaustive database for the pool boiling conditions.Keywords: experiment, boiling, bubbles, bubble dynamics, pool boiling
Procedia PDF Downloads 302681 The Relationship between Proximity to Sources of Industrial-Related Outdoor Air Pollution and Children Emergency Department Visits for Asthma in the Census Metropolitan Area of Edmonton, Canada, 2004/2005 to 2009/2010
Authors: Laura A. Rodriguez-Villamizar, Alvaro Osornio-Vargas, Brian H. Rowe, Rhonda J. Rosychuk
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Introduction/Objectives: The Census Metropolitan Area of Edmonton (CMAE) has important industrial emissions to the air from the Industrial Heartland Alberta (IHA) at the Northeast and the coal-fired power plants (CFPP) at the West. The objective of the study was to explore the presence of clusters of children asthma ED visits in the areas around the IHA and the CFPP. Methods: Retrospective data on children asthma ED visits was collected at the dissemination area (DA) level for children between 2 and 14 years of age, living in the CMAE between April 1, 2004, and March 31, 2010. We conducted a spatial analysis of disease clusters around putative sources with count (ecological) data using descriptive, hypothesis testing, and multivariable modeling analysis. Results: The mean crude rate of asthma ED visits was 9.3/1,000 children population per year during the study period. Circular spatial scan test for cases and events identified a cluster of children asthma ED visits in the DA where the CFPP are located in the Wabamum area. No clusters were identified around the IHA area. The multivariable models suggest that there is a significant decline in risk for children asthma ED visits as distance increases around the CFPP area this effect is modified at the SE direction with mean angle 125.58 degrees, where the risk increases with distance. In contrast, the regression models for IHA suggest that there is a significant increase in risk for children asthma ED visits as distance increases around the IHA area and this effect is modified at SW direction with mean angle 216.52 degrees, where the risk increases at shorter distances. Conclusions: Different methods for detecting clusters of disease consistently suggested the existence of a cluster of children asthma ED visits around the CFPP but not around the IHA within the CMAE. These results are probably explained by the direction of the air pollutants dispersion caused by the predominant and subdominant wind direction at each point. The use of different approaches to detect clusters of disease is valuable to have a better understanding of the presence, shape, direction and size of clusters of disease around pollution sources.Keywords: air pollution, asthma, disease cluster, industry
Procedia PDF Downloads 282