Search results for: element
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 2976

Search results for: element

306 Carbapenem Usage in Medical Wards: An Antibiotic Stewardship Feedback Project

Authors: Choon Seong Ng, P. Petrick, C. L. Lau

Abstract:

Background: Carbapenem-resistant isolates have been increasingly reported recently. Carbapenem stewardship is designed to optimize its usage particularly among medical wards with high prevalence of carbapenem prescriptions to combat such emerging resistance. Carbapenem stewardship programmes (CSP) can reduce antibiotic use but clinical outcome of such measures needs further evaluation. We examined this in a prospective manner using feedback mechanism. Methods: Our single-center prospective cohort study involved all carbapenem prescriptions across the medical wards (including medical patients admitted to intensive care unit) in a tertiary university hospital setting. The impact of such stewardship was analysed according to the accepted and the rejected groups. The primary endpoint was safety. Safety measure applied in this study was the death at 1 month. Secondary endpoints included length of hospitalisation and readmission. Results: Over the 19 months’ period, input from 144 carbapenem prescriptions was analysed on the basis of acceptance of our CSP recommendations on the use of carbapenems. Recommendations made were as follows : de-escalation of carbapenem; stopping the carbapenem; use for a short duration of 5-7 days; required prolonged duration in the case of carbapenem-sensitive Extended Spectrum Beta-Lactamases bacteremia; dose adjustment; and surgical intervention for removal of septic foci. De-escalation, shorten duration of carbapenem and carbapenem cessation comprised 79% of the recommendations. Acceptance rate was 57%. Those who accepted CSP recommendations had no increase in mortality (p = 0.92), had a shorter length of hospital stay (LOS) and had cost-saving. Infection-related deaths were found to be higher among those in the rejected group. Moreover, three rejected cases (6%) among all non-indicated cases (n = 50) were found to have developed carbapenem-resistant isolates. Lastly, Pitt’s bacteremia score appeared to be a key element affecting the carbapenem prescription’s behaviour in this trial. Conclusions: Carbapenem stewardship program in the medical wards not only saves money, but most importantly it is safe and does not harm the patients with added benefits of reducing the length of hospital stay. However, more time is needed to engage the primary clinical teams by formal clinical presentation and immediate personal feedback by senior Infectious Disease (ID) personnel to increase its acceptance.

Keywords: audit and feedback, carbapenem stewardship, medical wards, university hospital

Procedia PDF Downloads 163
305 Cognitive Translation and Conceptual Wine Tasting Metaphors: A Corpus-Based Research

Authors: Christine Demaecker

Abstract:

Many researchers have underlined the importance of metaphors in specialised language. Their use of specific domains helps us understand the conceptualisations used to communicate new ideas or difficult topics. Within the wide area of specialised discourse, wine tasting is a very specific example because it is almost exclusively metaphoric. Wine tasting metaphors express various conceptualisations. They are not linguistic but rather conceptual, as defined by Lakoff & Johnson. They correspond to the linguistic expression of a mental projection from a well-known or more concrete source domain onto the target domain, which is the taste of wine. But unlike most specialised terminologies, the vocabulary is never clearly defined. When metaphorical terms are listed in dictionaries, their definitions remain vague, unclear, and circular. They cannot be replaced by literal linguistic expressions. This makes it impossible to transfer them into another language with the traditional linguistic translation methods. Qualitative research investigates whether wine tasting metaphors could rather be translated with the cognitive translation process, as well described by Nili Mandelblit (1995). The research is based on a corpus compiled from two high-profile wine guides; the Parker’s Wine Buyer’s Guide and its translation into French and the Guide Hachette des Vins and its translation into English. In this small corpus with a total of 68,826 words, 170 metaphoric expressions have been identified in the original English text and 180 in the original French text. They have been selected with the MIPVU Metaphor Identification Procedure developed at the Vrije Universiteit Amsterdam. The selection demonstrates that both languages use the same set of conceptualisations, which are often combined in wine tasting notes, creating conceptual integrations or blends. The comparison of expressions in the source and target texts also demonstrates the use of the cognitive translation approach. In accordance with the principle of relevance, the translation always uses target language conceptualisations, but compared to the original, the highlighting of the projection is often different. Also, when original metaphors are complex with a combination of conceptualisations, at least one element of the original metaphor underlies the target expression. This approach perfectly integrates into Lederer’s interpretative model of translation (2006). In this triangular model, the transfer of conceptualisation could be included at the level of ‘deverbalisation/reverbalisation’, the crucial stage of the model, where the extraction of meaning combines with the encyclopedic background to generate the target text.

Keywords: cognitive translation, conceptual integration, conceptual metaphor, interpretative model of translation, wine tasting metaphor

Procedia PDF Downloads 101
304 Prospects of Iraq’s Maritime Openness and Their Effect on Its Economy

Authors: Mohanad Hammad

Abstract:

Port institutions serve as a link connecting the land areas that receive the goods and the areas from where ships sail. These areas hold great significance for the conversion of goods into commodities of economic value, capable of meeting the needs of the society. Development of ports constitutes a fundamental component of the comprehensive economic development process. Recognizing this fact, developing countries have always resorted to this infrastructural element to resolve the numerous problems they face, taking into account its contribution to the reformation of their economic conditions. Iraqi ports have played a major role in boosting the commercial movement in Iraq, as they are the starting point of its oil exports and a key constituent in fulfilling the consumer and production needs of the various economic sectors of Iraq. With the Gulf wars and the economic blockade, Iraqi ports have continued to deteriorate and become unable to perform their functions as first-generation ports, prompting Iraq to use the ports of neighboring countries such as Jordan's Aqaba commercial port. Meanwhile, Iraqi ports face strong competition from the ports of neighboring countries, which have achieved progress and advancement as opposed to the declining performance and efficiency of Iraqi ports. The great developments in the economic conditions of Iraq lay a too great burden on the Iraqi maritime transport and ports, which require development in order to be able to meet the challenges arising from the fierce international and regional competition in the markets. Therefore, it is necessary to find appropriate solutions in support of the role that can be played by Iraqi ports in serving Iraq's foreign trade transported by sea and in keeping up with the development of foreign trade. Thus, this research aims at tackling the current situation of the Iraqi ports and their commercial activity and studying the problems and obstacles they face. The research also studies the future prospects of these ports, the potentials of maritime openness to Iraq under the fierce competition of neighboring ports, and the possibility of enhancing Iraqi ports’ competitiveness. Among the results produced by this research is the future scenario it proposes for Iraqi ports, mainly represented in the establishment of Al-Faw Port, which will contribute to a greater openness of maritime transport in Iraq, and the rehabilitation and expansion of existing ports. This research seeks to develop solutions to Iraq ports so that they can be repositioned as a vital means of promoting economic development.

Keywords: maritime transport, port, future prospects, regional integration

Procedia PDF Downloads 124
303 Language in Court: Ideology, Power and Cognition

Authors: Mehdi Damaliamiri

Abstract:

Undoubtedly, the power of language is hardly a new topic; indeed, the persuasive power of language accompanied by ideology has long been recognized in different aspects of life. The two and a half thousand-year-old Bisitun inscriptions in Iran, proclaiming the victories of the Persian King, Darius, are considered by some historians to have been an early example of the use of propaganda. Added to this, the modern age is the true cradle of fully-fledged ideologies and the ongoing process of centrifugal ideologization. The most visible work on ideology today within the field of linguistics is “Critical Discourse Analysis” (CDA). The focus of CDA is on “uncovering injustice, inequality, taking sides with the powerless and suppressed” and making “mechanisms of manipulation, discrimination, demagogy, and propaganda explicit and transparent.” possible way of relating language to ideology is to propose that ideology and language are inextricably intertwined. From this perspective, language is always ideological, and ideology depends on the language. All language use involves ideology, and so ideology is ubiquitous – in our everyday encounters, as much as in the business of the struggle for power within and between the nation-states and social statuses. At the same time, ideology requires language. Its key characteristics – its power and pervasiveness, its mechanisms for continuity and for change – all come out of the inner organization of language. The two phenomena are homologous: they share the same evolutionary trajectory. To get a more robust portrait of the power and ideology, we need to examine its potential place in the structure, and consider how such structures pattern in terms of the functional elements which organize meanings in the clause. This is based on the belief that all grammatical, including syntactic, knowledge is stored mentally as constructions have become immensely popular. When the structure of the clause is taken into account, the power and ideology have a preference for Complement over Subject and Adjunct. The subject is a central interpersonal element in discourse: it is one of two elements that form the central interactive nub of a proposition. Conceptually, there are countless ways of construing a given event and linguistically, a variety of grammatical devices that are usually available as alternate means of coding a given conception, such as political crime and corruption. In the theory of construal, then, which, like transitivity in Halliday, makes options available, Cognitive Linguistics can offer a cognitive account of ideology in language, where ideology is made possible by the choices a language allows for representing the same material situation in different ways. The possibility of promoting alternative construals of the same reality means that any particular choice in representation is always ideologically constrained or motivated and indicates the perspective and interests of the text-producer.

Keywords: power, ideology, court, discourse

Procedia PDF Downloads 137
302 Petrology and Petrochemistry of Basement Rocks in Ila Orangun Area, Southwestern Nigeria

Authors: Jayeola A. O., Ayodele O. S., Olususi J. I.

Abstract:

From field studies, six (6) lithological units were identified to be common around the study area, which includes quartzites, granites, granite gneiss, porphyritic granites, amphibolite and pegmatites. Petrographical analysis was done to establish the major mineral assemblages and accessory minerals present in selected rock samples, which represents the major rock types in the area. For the purpose of this study, twenty (20) pulverized rock samples were taken to the laboratory for geochemical analysis with their results used in the classification, as well as suggest the geochemical attributes of the rocks. Results from petrographical studies of the rocks under both plane and cross polarized lights revealed the major minerals identified under thin sections to include quartz, feldspar, biotite, hornblende, plagioclase and muscovite with opaque other accessory minerals, which include actinolite, spinel and myrmekite. Geochemical results obtained and interpreted using various geochemical plots or discrimination plots all classified the rocks in the area as belonging to both the peralkaline metaluminous and peraluminous types. Results for the major oxides ratios produced for Na₂O/K₂O, Al₂O₃/Na₂O + CaO + K₂O and Na₂O + CaO + K₂O/Al₂O₃ show the excess of alumina, Al₂O₃ over the alkaline Na₂O +CaO +K₂O thus suggesting peraluminous rocks. While the excess of the alkali over the alumina suggests the peralkaline metaluminous rock type. The results of correlation coefficient show a perfect strong positive correlation, which shows that they are of same geogenic sources, while negative correlation coefficient values indicate a perfect weak negative correlation, suggesting that they are of heterogeneous geogenic sources. From factor analysis, five component groups were identified as Group 1 consists of Ag-Cr-Ni elemental associations suggesting Ag, Cr, and Ni mineralization, predicting the possibility of sulphide mineralization. in the study area. Group ll and lll consist of As-Ni-Hg-Fe-Sn-Co-Pb-Hg element association, which are pathfinder elements to the mineralization of gold. Group 1V and V consist of Cd-Cu-Ag-Co-Zn, which concentrations are significant to elemental associations and mineralization. In conclusion, from the potassium radiometric anomaly map produced, the eastern section (northeastern and southeastern) is observed to be the hot spot and mineralization zone for the study area.

Keywords: petrography, Ila Orangun, petrochemistry, pegmatites, peraluminous

Procedia PDF Downloads 30
301 Polyphenol-Rich Aronia Melanocarpa Juice Consumption and Line-1 Dna Methylation in a Cohort at Cardiovascular Risk

Authors: Ljiljana Stojković, Manja Zec, Maja Zivkovic, Maja Bundalo, Marija Glibetić, Dragan Alavantić, Aleksandra Stankovic

Abstract:

Cardiovascular disease (CVD) is associated with alterations in DNA methylation, the latter modulated by dietary polyphenols. The present pilot study (part of the original clinical study registered as NCT02800967 at www.clinicaltrials.gov) aimed to investigate the impact of 4-week daily consumption of polyphenol-rich Aronia melanocarpa juice on Long Interspersed Nucleotide Element-1 (LINE-1) methylation in peripheral blood leukocytes, in subjects (n=34, age of 41.1±6.6 years) at moderate CVD risk, including an increased body mass index, central obesity, high normal blood pressure and/or dyslipidemia. The goal was also to examine whether factors known to affect DNA methylation, such as folate intake levels, MTHFR C677T gene variant, as well as the anthropometric and metabolic parameters, modulated the LINE-1 methylation levels upon consumption of polyphenol-rich Aronia juice. The experimental analysis of LINE-1 methylation was done by the MethyLight method. MTHFR C677T genotypes were determined by the polymerase chain reaction-restriction fragment length polymorphism method. Folate intake was assessed by processing the data from the food frequency questionnaire and repeated 24-hour dietary recalls. Serum lipid profile was determined by using Roche Diagnostics kits. The statistical analyses were performed using the Statistica software package. In women, after vs. before the treatment period, a significant decrease in LINE-1 methylation levels was observed (97.54±1.50% vs. 98.39±0.86%, respectively; P=0.01). The change (after vs. before treatment) in LINE-1 methylation correlated directly with MTHFR 677T allele presence, average daily folate intake and the change in serum low-density lipoprotein cholesterol, while inversely with the change in serum triacylglycerols (R=0.72, R2=0.52, adjusted R2=0.36, P=0.03). The current results imply potential cardioprotective effects of habitual polyphenol-rich Aronia juice consumption achieved through the modifications of DNA methylation pattern in subjects at CVD risk, which should be further confirmed. Hence, the precision nutrition-driven modulations of DNA methylation may become targets for new approaches in the prevention and treatment of CVD.

Keywords: Aronia melanocarpa, cardiovascular risk, LINE-1, methylation, peripheral blood leukocytes, polyphenol

Procedia PDF Downloads 168
300 Souk Waqif in Old Doha, Qatar: Cultural Heritage, Urban Regeneration, and Sustainability

Authors: Djamel Boussaa

Abstract:

Cultural heritage and tourism have become during the last two decades dynamic areas of development in the world. The idea of heritage is crucial to the critical decision-making process as to how irreplaceable resources are to be utilized by people of the present or conserved for future generations in a fast changing world. In view of the importance of ‘heritage’ to the development of a tourist destination the emphasis on developing appropriate adaptive reuse strategies cannot be overemphasized. In October 1999, the 12th general assembly of the ICOMOS in Mexico stated, that in the context of sustainable development, two interrelated issues need urgent attention, cultural tourism and historic towns and cities. These two issues underscore the fact that historic resources are non-renewable, belonging to all of humanity. Without adequate adaptive reuse actions to ensure a sustainable future for these historic resources, may lead to their complete vanishing. The growth of tourism and its role in dispersing cultural heritage to everyone is developing rapidly. According to the World Tourism Organization, natural and cultural heritage resources are and will remain motivating factors for travel in the foreseeable future. According to the experts, people choose travel destinations where they can learn about traditional and distinct cultures in their historic context. The Qatar rich urban heritage is now being recognized as a valuable resource for future development. This paper discusses the role of cultural heritage and tourism in regenerating Souk Waqif, and consequently the city of Doha. Therefore, in order to use cultural heritage wisely, it will be necessary to position heritage as an essential element of sustainable development, giving particular attention to cultural heritage and tourism. The research methodology is based on an empirical survey of the situation, based on several visits, meetings and interviews with the local heritage players. The rehabilitation project initiated since 2004 will be examined and assessed. Therefore, there is potential to assess the situation and propose directions for a sustainable future to this historic landmark. Conservation for the sake of conservation appears to be an outdated concept. Many irreplaceable natural and cultural sites are being compromised because local authorities are not giving economic consideration to the value of rehabilitating such sites. The question to be raised here is 'How can cultural heritage be used wisely for tourism without compromising its social sustainability within the emerging global world?'

Keywords: cultural heritage, tourism, regeneration, economy, social sustainability

Procedia PDF Downloads 397
299 Laser-Dicing Modeling: Implementation of a High Accuracy Tool for Laser-Grooving and Cutting Application

Authors: Jeff Moussodji, Dominique Drouin

Abstract:

The highly complex technology requirements of today’s integrated circuits (ICs), lead to the increased use of several materials types such as metal structures, brittle and porous low-k materials which are used in both front end of line (FEOL) and back end of line (BEOL) process for wafer manufacturing. In order to singulate chip from wafer, a critical laser-grooving process, prior to blade dicing, is used to remove these layers of materials out of the dicing street. The combination of laser-grooving and blade dicing allows to reduce the potential risk of induced mechanical defects such micro-cracks, chipping, on the wafer top surface where circuitry is located. It seems, therefore, essential to have a fundamental understanding of the physics involving laser-dicing in order to maximize control of these critical process and reduce their undesirable effects on process efficiency, quality, and reliability. In this paper, the study was based on the convergence of two approaches, numerical and experimental studies which allowed us to investigate the interaction of a nanosecond pulsed laser and BEOL wafer materials. To evaluate this interaction, several laser grooved samples were compared with finite element modeling, in which three different aspects; phase change, thermo-mechanical and optic sensitive parameters were considered. The mathematical model makes it possible to highlight a groove profile (depth, width, etc.) of a single pulse or multi-pulses on BEOL wafer material. Moreover, the heat affected zone, and thermo-mechanical stress can be also predicted as a function of laser operating parameters (power, frequency, spot size, defocus, speed, etc.). After modeling validation and calibration, a satisfying correlation between experiment and modeling, results have been observed in terms of groove depth, width and heat affected zone. The study proposed in this work is a first step toward implementing a quick assessment tool for design and debug of multiple laser grooving conditions with limited experiments on hardware in industrial application. More correlations and validation tests are in progress and will be included in the full paper.

Keywords: laser-dicing, nano-second pulsed laser, wafer multi-stack, multiphysics modeling

Procedia PDF Downloads 178
298 Effect of Dietary Organic Zinc Supplementation on Immunocompetance and Reproductive Performance in Rats

Authors: D. Nagalakshmi, S. Parashuramulu K. Sadasiva Rao, G. Aruna, L. Vikram

Abstract:

The zinc (Zn) is the second most abundant trace element in mammals and birds, forming structural component of over 300 enzymes, playing an important role in anti-oxidant defense, immune response and reproduction. Organic trace minerals are more readily absorbed from the digestive tract and more biologically available compared with its inorganic salt. Thus, the present study was undertaken on 60 adult female Sprague Dawley rats (275±2.04 g) for experimental duration of 12 weeks to investigate the effect of dietary Zn supplementation from various organic sources on immunity, reproduction, oxidative defense mechanism and blood biochemical profile. The rats were randomly allotted to 30 replicates (2 per replicate) which were in turn randomly allotted to 5 dietary treatments varying in Zn source i.e., one inorganic source (Zn carbonate) and 4 organic sources (Zn-proteinate, Zn-propionate, Zn-amino acid complex and Zn-methionine) so as to supply NRC recommended Zn concentration (12 ppm Zn). Supplementation of organic Zn had no effect on various haematological and serum biochemical constituents compared to inorganic Zn fed rats. The TBARS and protein carbonyls concentration in liver indicative of oxidative stress was comparable between various organic and inorganic groups. The glutathione reductase activity in haemolysate (P<0.05) and reduced glutathione concentration in liver (P<0.01) was higher when fed organic Zn and RBC catalase activity was higher (P<0.01) on Zn methionine compared to other organic sources tested and the inorganic source. The humoral immune response assessed as antibody titres against sheep RBC was higher (P<0.05) when fed organic sources of zinc compared to inorganic source. The cell mediated immune response expressed as delayed type hypersensitivity reaction was higher (P<0.05) in rats fed Zn propionate with no effect of other organic Zn sources. The serum progesterone concentration was higher (P<0.05) in rats fed organic Zn sources compared to inorganic zinc. The data on ovarian folliculogenesis indicated that organic Zn supplementation increased (P<0.05) the number of graafian follicles and corpus luteum with no effect on primary, secondary and tertiary follicle number. The study indicated that rats fed organic sources of Zn had higher antioxidant enzyme activities, immune response and serum progesterone concentration with higher number of mature follicles. Though the effect of feeding various organic sources were comparable, rats fed zinc methionine had higher antioxidant activity and cell mediated immune response was higher in rats on Zn propionate.

Keywords: organic zinc, immune, rats, reproductive

Procedia PDF Downloads 261
297 An Optimal Control Method for Reconstruction of Topography in Dam-Break Flows

Authors: Alia Alghosoun, Nabil El Moçayd, Mohammed Seaid

Abstract:

Modeling dam-break flows over non-flat beds requires an accurate representation of the topography which is the main source of uncertainty in the model. Therefore, developing robust and accurate techniques for reconstructing topography in this class of problems would reduce the uncertainty in the flow system. In many hydraulic applications, experimental techniques have been widely used to measure the bed topography. In practice, experimental work in hydraulics may be very demanding in both time and cost. Meanwhile, computational hydraulics have served as an alternative for laboratory and field experiments. Unlike the forward problem, the inverse problem is used to identify the bed parameters from the given experimental data. In this case, the shallow water equations used for modeling the hydraulics need to be rearranged in a way that the model parameters can be evaluated from measured data. However, this approach is not always possible and it suffers from stability restrictions. In the present work, we propose an adaptive optimal control technique to numerically identify the underlying bed topography from a given set of free-surface observation data. In this approach, a minimization function is defined to iteratively determine the model parameters. The proposed technique can be interpreted as a fractional-stage scheme. In the first stage, the forward problem is solved to determine the measurable parameters from known data. In the second stage, the adaptive control Ensemble Kalman Filter is implemented to combine the optimality of observation data in order to obtain the accurate estimation of the topography. The main features of this method are on one hand, the ability to solve for different complex geometries with no need for any rearrangements in the original model to rewrite it in an explicit form. On the other hand, its achievement of strong stability for simulations of flows in different regimes containing shocks or discontinuities over any geometry. Numerical results are presented for a dam-break flow problem over non-flat bed using different solvers for the shallow water equations. The robustness of the proposed method is investigated using different numbers of loops, sensitivity parameters, initial samples and location of observations. The obtained results demonstrate high reliability and accuracy of the proposed techniques.

Keywords: erodible beds, finite element method, finite volume method, nonlinear elasticity, shallow water equations, stresses in soil

Procedia PDF Downloads 106
296 Knowledge Management Barriers: A Statistical Study of Hardware Development Engineering Teams within Restricted Environments

Authors: Nicholas S. Norbert Jr., John E. Bischoff, Christopher J. Willy

Abstract:

Knowledge Management (KM) is globally recognized as a crucial element in securing competitive advantage through building and maintaining organizational memory, codifying and protecting intellectual capital and business intelligence, and providing mechanisms for collaboration and innovation. KM frameworks and approaches have been developed and defined identifying critical success factors for conducting KM within numerous industries ranging from scientific to business, and for ranges of organization scales from small groups to large enterprises. However, engineering and technical teams operating within restricted environments are subject to unique barriers and KM challenges which cannot be directly treated using the approaches and tools prescribed for other industries. This research identifies barriers in conducting KM within Hardware Development Engineering (HDE) teams and statistically compares significance to barriers upholding the four KM pillars of organization, technology, leadership, and learning for HDE teams. HDE teams suffer from restrictions in knowledge sharing (KS) due to classification of information (national security risks), customer proprietary restrictions (non-disclosure agreement execution for designs), types of knowledge, complexity of knowledge to be shared, and knowledge seeker expertise. As KM evolved leveraging information technology (IT) and web-based tools and approaches from Web 1.0 to Enterprise 2.0, KM may also seek to leverage emergent tools and analytics including expert locators and hybrid recommender systems to enable KS across barriers of the technical teams. The research will test hypothesis statistically evaluating if KM barriers for HDE teams affect the general set of expected benefits of a KM System identified through previous research. If correlations may be identified, then generalizations of success factors and approaches may also be garnered for HDE teams. Expert elicitation will be conducted using a questionnaire hosted on the internet and delivered to a panel of experts including engineering managers, principal and lead engineers, senior systems engineers, and knowledge management experts. The feedback to the questionnaire will be processed using analysis of variance (ANOVA) to identify and rank statistically significant barriers of HDE teams within the four KM pillars. Subsequently, KM approaches will be recommended for upholding the KM pillars within restricted environments of HDE teams.

Keywords: engineering management, knowledge barriers, knowledge management, knowledge sharing

Procedia PDF Downloads 244
295 Predicting the Effect of Vibro Stone Column Installation on Performance of Reinforced Foundations

Authors: K. Al Ammari, B. G. Clarke

Abstract:

Soil improvement using vibro stone column techniques consists of two main parts: (1) the installed load bearing columns of well-compacted, coarse-grained material and (2) the improvements to the surrounding soil due to vibro compaction. Extensive research work has been carried out over the last 20 years to understand the improvement in the composite foundation performance due to the second part mentioned above. Nevertheless, few of these studies have tried to quantify some of the key design parameters, namely the changes in the stiffness and stress state of the treated soil, or have consider these parameters in the design and calculation process. Consequently, empirical and conservative design methods are still being used by ground improvement companies with a significant variety of results in engineering practice. Two-dimensional finite element study to develop an axisymmetric model of a single stone column reinforced foundation was performed using PLAXIS 2D AE to quantify the effect of the vibro installation of this column in soft saturated clay. Settlement and bearing performance were studied as an essential part of the design and calculation of the stone column foundation. Particular attention was paid to the large deformation in the soft clay around the installed column caused by the lateral expansion. So updated mesh advanced option was taken in the analysis. In this analysis, different degrees of stone column lateral expansions were simulated and numerically analyzed, and then the changes in the stress state, stiffness, settlement performance and bearing capacity were quantified. It was found that application of radial expansion will produce a horizontal stress in the soft clay mass that gradually decrease as the distance from the stone column axis increases. The excess pore pressure due to the undrained conditions starts to dissipate immediately after finishing the column installation, allowing the horizontal stress to relax. Changes in the coefficient of the lateral earth pressure K ٭, which is very important in representing the stress state, and the new stiffness distribution in the reinforced clay mass, were estimated. More encouraging results showed that increasing the expansion during column installation has a noticeable effect on improving the bearing capacity and reducing the settlement of reinforced ground, So, a design method should include this significant effect of the applied lateral displacement during the stone column instillation in simulation and numerical analysis design.

Keywords: bearing capacity, design, installation, numerical analysis, settlement, stone column

Procedia PDF Downloads 356
294 How to Reach Net Zero Emissions? On the Permissibility of Negative Emission Technologies and the Danger of Moral Hazards

Authors: Hanna Schübel, Ivo Wallimann-Helmer

Abstract:

In order to reach the goal of the Paris Agreement to not overshoot 1.5°C of warming above pre-industrial levels, various countries including the UK and Switzerland have committed themselves to net zero emissions by 2050. The employment of negative emission technologies (NETs) is very likely going to be necessary for meeting these national objectives as well as other internationally agreed climate targets. NETs are methods of removing carbon from the atmosphere and are thus a means for addressing climate change. They range from afforestation to technological measures such as direct air capture and carbon storage (DACCS), where CO2 is captured from the air and stored underground. As all so-called geoengineering technologies, the development and deployment of NETs are often subject to moral hazard arguments. As these technologies could be perceived as an alternative to mitigation efforts, so the argument goes, they are potentially a dangerous distraction from the main target of mitigating emissions. We think that this is a dangerous argument to make as it may hinder the development of NETs which are an essential element of net zero emission targets. In this paper we argue that the moral hazard argument is only problematic if we do not reflect upon which levels of emissions are at stake in order to meet net zero emissions. In response to the moral hazard argument we develop an account of which levels of emissions in given societies should be mitigated and not be the target of NETs and which levels of emissions can legitimately be a target of NETs. For this purpose, we define four different levels of emissions: the current level of individual emissions, the level individuals emit in order to appear in public without shame, the level of a fair share of individual emissions in the global budget, and finally the baseline of net zero emissions. At each level of emissions there are different subjects to be assigned responsibilities if societies and/or individuals are committed to the target of net zero emissions. We argue that all emissions within one’s fair share do not demand individual mitigation efforts. The same holds with regard to individuals and the baseline level of emissions necessary to appear in public in their societies without shame. Individuals are only under duty to reduce their emissions if they exceed this baseline level. This is different for whole societies. Societies demanding more emissions to appear in public without shame than the individual fair share are under duty to foster emission reductions and are not legitimate to reduce by introducing NETs. NETs are legitimate for reducing emissions only below the level of fair shares and for reaching net zero emissions. Since access to NETs to achieve net zero emissions demands technology not affordable to individuals there are also no full individual responsibilities to achieve net zero emissions. This is mainly a responsibility of societies as a whole.

Keywords: climate change, mitigation, moral hazard, negative emission technologies, responsibility

Procedia PDF Downloads 94
293 Multiscale Modelling of Textile Reinforced Concrete: A Literature Review

Authors: Anicet Dansou

Abstract:

Textile reinforced concrete (TRC)is increasingly used nowadays in various fields, in particular civil engineering, where it is mainly used for the reinforcement of damaged reinforced concrete structures. TRC is a composite material composed of multi- or uni-axial textile reinforcements coupled with a fine-grained cementitious matrix. The TRC composite is an alternative solution to the traditional Fiber Reinforcement Polymer (FRP) composite. It has good mechanical performance and better temperature stability but also, it makes it possible to meet the criteria of sustainable development better.TRCs are highly anisotropic composite materials with nonlinear hardening behavior; their macroscopic behavior depends on multi-scale mechanisms. The characterization of these materials through numerical simulation has been the subject of many studies. Since TRCs are multiscale material by definition, numerical multi-scale approaches have emerged as one of the most suitable methods for the simulation of TRCs. They aim to incorporate information pertaining to microscale constitute behavior, mesoscale behavior, and macro-scale structure response within a unified model that enables rapid simulation of structures. The computational costs are hence significantly reduced compared to standard simulation at a fine scale. The fine scale information can be implicitly introduced in the macro scale model: approaches of this type are called non-classical. A representative volume element is defined, and the fine scale information are homogenized over it. Analytical and computational homogenization and nested mesh methods belong to these approaches. On the other hand, in classical approaches, the fine scale information are explicitly introduced in the macro scale model. Such approaches pertain to adaptive mesh refinement strategies, sub-modelling, domain decomposition, and multigrid methods This research presents the main principles of numerical multiscale approaches. Advantages and limitations are identified according to several criteria: the assumptions made (fidelity), the number of input parameters required, the calculation costs (efficiency), etc. A bibliographic study of recent results and advances and of the scientific obstacles to be overcome in order to achieve an effective simulation of textile reinforced concrete in civil engineering is presented. A comparative study is further carried out between several methods for the simulation of TRCs used for the structural reinforcement of reinforced concrete structures.

Keywords: composites structures, multiscale methods, numerical modeling, textile reinforced concrete

Procedia PDF Downloads 75
292 Ultra-Wideband Antennas for Ultra-Wideband Communication and Sensing Systems

Authors: Meng Miao, Jeongwoo Han, Cam Nguyen

Abstract:

Ultra-wideband (UWB) time-domain impulse communication and radar systems use ultra-short duration pulses in the sub-nanosecond regime, instead of continuous sinusoidal waves, to transmit information. The pulse directly generates a very wide-band instantaneous signal with various duty cycles depending on specific usages. In UWB systems, the total transmitted power is spread over an extremely wide range of frequencies; the power spectral density is extremely low. This effectively results in extremely small interference to other radio signals while maintains excellent immunity to interference from these signals. UWB devices can therefore work within frequencies already allocated for other radio services, thus helping to maximize this dwindling resource. Therefore, impulse UWB technique is attractive for realizing high-data-rate, short-range communications, ground penetrating radar (GPR), and military radar with relatively low emission power levels. UWB antennas are the key element dictating the transmitted and received pulse shape and amplitude in both time and frequency domain. They should have good impulse response with minimal distortion. To facilitate integration with transmitters and receivers employing microwave integrated circuits, UWB antennas enabling direct integration are preferred. We present the development of two UWB antennas operating from 3.1 to 10.6 GHz and 0.3-6 GHz for UWB systems that provide direct integration with microwave integrated circuits. The operation of these antennas is based on the principle of wave propagation on a non-uniform transmission line. Time-domain EM simulation is conducted to optimize the antenna structures to minimize reflections occurring at the open-end transition. Calculated and measured results of these UWB antennas are presented in both frequency and time domains. The antennas have good time-domain responses. They can transmit and receive pulses effectively with minimum distortion, little ringing, and small reflection, clearly demonstrating the signal fidelity of the antennas in reproducing the waveform of UWB signals which is critical for UWB sensors and communication systems. Good performance together with seamless microwave integrated-circuit integration makes these antennas good candidates not only for UWB applications but also for integration with printed-circuit UWB transmitters and receivers.

Keywords: antennas, ultra-wideband, UWB, UWB communication systems, UWB radar systems

Procedia PDF Downloads 215
291 Origins of the Tattoo: Decoding the Ancient Meanings of Terrestrial Body Art to Establish a Connection between the Natural World and Humans Today

Authors: Sangeet Anand

Abstract:

Body art and tattooing have long been practiced as a form of self-expression for centuries, and this study studies and analyzes the pertinence of tattoo culture in our everyday lives and ancient past. Individuals of different cultures represent ideas, practices, and elements of their cultures through symbolic representation. These symbols come in all shapes and sizes and can be as simple as the makeup you put on every day to something more permanent such as a tattoo. In the long run, these individuals who choose to display art on their bodies are seeking to express their individuality. In addition, these visuals are ultimately a reflection of our own appropriate cultures deem as beautiful, important, and powerful to the human eye. They make us known to the world and give us a plausible identity in an ever-changing world. We have lived through and seen a rise in hippie culture today. This type of bodily decoration displayed by this fad has made it seem as though body art is a visual language that is relatively new. But quite to the contrary, it is not. Through cultural symbolic exploration, we can answer key questions to ideas that have been raised for centuries. Through careful, in-depth interviews, this study takes a broad subject matter-art, and symbolism-and culminates it into a deeper philosophical connection between the world and its past. The basic methodologies used in this sociocultural study include interview questionnaires and textual analysis, which encompass a subject and interviewer as well as source material. The major findings of this study contain a distinct connection between cultural heritage and the day-to-day likings of an individual. The participant that was studied during this project demonstrated a clear passion for hobbies that were practiced even by her ancestors. We can conclude, through these findings, that there is a deeper cultural connection between modern day humans, the first humans, and the surrounding environments. Our symbols today are a direct reflection of the elements of nature that our human ancestors were exposed to, and, through cultural acceptance, we can adorn ourselves with these representations to help others identify our pasts. Body art embraces the different aspects of different cultures and holds significance, tells stories, and persists, even as the human population rapidly integrates. With this pattern, our human descendents will continue to represent their cultures and identities in the future. Body art is an integral element in understanding how and why people identify with certain aspects of life over others and broaden the scope for conducting more analysis cross-culturally.

Keywords: natural, symbolism, tattoo, terrestrial

Procedia PDF Downloads 80
290 Facile Wick and Oil Flame Synthesis of High-Quality Hydrophilic Carbon Nano Onions for Flexible Binder-Free Supercapacitor

Authors: Debananda Mohapatra, Subramanya Badrayyana, Smrutiranjan Parida

Abstract:

Carbon nano-onions (CNOs) are the spherical graphitic nanostructures composed of concentric shells of graphitic carbon can be hypothesized as the intermediate state between fullerenes and graphite. These are very important members in fullerene family also known as the multi-shelled fullerenes can be envisioned as promising supercapacitor electrode with high energy & power density as they provide easy access to ions at electrode-electrolyte interface due to their curvature. There is still very sparse report concerning on CNOs as electrode despite having an excellent electrodechemical performance record due to their unavailability and lack of convenient methods for their high yield preparation and purification. Keeping all these current pressing issues in mind, we present a facile scalable and straightforward flame synthesis method of pure and highly dispersible CNOs without contaminated by any other forms of carbon; hence, a post processing purification procedure is not necessary. To the best of our knowledge, this is the very first time; we developed an extremely simple, light weight, novel inexpensive, flexible free standing pristine CNOs electrode without using any binder element. Locally available daily used cotton wipe has been used for fabrication of such an ideal electrode by ‘dipping and drying’ process providing outstanding stretchability and mechanical flexibility with strong adhesion between CNOs and porous wipe. The specific capacitance 102 F/g, energy density 3.5 Wh/kg and power density 1224 W/kg at 20 mV/s scan rate are the highest values that ever recorded and reported so far in symmetrical two electrode cell configuration with 1M Na2SO4 electrolyte; indicating a very good synthesis conditions employed with optimum pore size in agreement with electrolyte ion size. This free standing CNOs electrode also showed an excellent cyclic performance and stability retaining 95% original capacity after 5000 charge –discharge cycles. Furthermore, this unique method not only affords binder free - freestanding electrode but also provide a general way of fabricating such multifunctional promising CNOs based nanocomposites for their potential device applications in flexible solar cells and lithium-ion batteries.

Keywords: binder-free, flame synthesis, flexible, carbon nano onion

Procedia PDF Downloads 171
289 Modeling of an Insulin Mircopump

Authors: Ahmed Slami, Med El Amine Brixi Nigassa, Nassima Labdelli, Sofiane Soulimane, Arnaud Pothier

Abstract:

Many people suffer from diabetes, a disease marked by abnormal levels of sugar in the blood; 285 million people have diabetes, 6.6% of the world adult population (in 2010), according to the International Diabetes Federation. Insulin medicament is invented to be injected into the body. Generally, the injection requires the patient to do it manually. However, in many cases he will be unable to inject the drug, saw that among the side effects of hyperglycemia is the weakness of the whole body. The researchers designed a medical device that injects insulin too autonomously by using micro-pumps. Many micro-pumps of concepts have been investigated during the last two decades for injecting molecules in blood or in the body. However, all these micro-pumps are intended for slow infusion of drug (injection of few microliters by minute). Now, the challenge is to develop micro-pumps for fast injections (1 microliter in 10 seconds) with accuracy of the order of microliter. Recently, studies have shown that only piezoelectric actuators can achieve this performance, knowing that few systems at the microscopic level were presented. These reasons lead us to design new smart microsystems injection drugs. Therefore, many technological advances are still to achieve the improvement of materials to their uses, while going through their characterization and modeling action mechanisms themselves. Moreover, it remains to study the integration of the piezoelectric micro-pump in the microfluidic platform features to explore and evaluate the performance of these new micro devices. In this work, we propose a new micro-pump model based on piezoelectric actuation with a new design. Here, we use a finite element model with Comsol software. Our device is composed of two pumping chambers, two diaphragms and two actuators (piezoelectric disks). The latter parts will apply a mechanical force on the membrane in a periodic manner. The membrane deformation allows the fluid pumping, the suction and discharge of the liquid. In this study, we present the modeling results as function as device geometry properties, films thickness, and materials properties. Here, we demonstrate that we can achieve fast injection. The results of these simulations will provide quantitative performance of our micro-pumps. Concern the spatial actuation, fluid rate and allows optimization of the fabrication process in terms of materials and integration steps.

Keywords: COMSOL software, piezoelectric, micro-pump, microfluidic

Procedia PDF Downloads 321
288 Dual-Phase High Entropy (Ti₀.₂₅V₀.₂₅Zr₀.₂₅Hf₀.₂₅) BxCy Ceramics Produced by Spark Plasma Sintering

Authors: Ana-Carolina Feltrin, Daniel Hedman, Farid Akhtar

Abstract:

High entropy ceramic (HEC) materials are characterized by their compositional disorder due to different metallic element atoms occupying the cation position and non-metal elements occupying the anion position. Several studies have focused on the processing and characterization of high entropy carbides and high entropy borides, as these HECs present interesting mechanical and chemical properties. A few studies have been published on HECs containing two non-metallic elements in the composition. Dual-phase high entropy (Ti₀.₂₅V₀.₂₅Zr₀.₂₅Hf₀.₂₅)BxCy ceramics with different amounts of x and y, (0.25 HfC + 0.25 ZrC + 0.25 VC + 0.25 TiB₂), (0.25 HfC + 0.25 ZrC + 0.25 VB2 + 0.25 TiB₂) and (0.25 HfC + 0.25 ZrB2 + 0.25 VB2 + 0.25 TiB₂) were sintered from boride and carbide precursor powders using SPS at 2000°C with holding time of 10 min, uniaxial pressure of 50 MPa and under Ar atmosphere. The sintered specimens formed two HEC phases: a Zr-Hf rich FCC phase and a Ti-V HCP phase, and both phases contained all the metallic elements from 5-50 at%. Phase quantification analysis of XRD data revealed that the molar amount of hexagonal phase increased with increased mole fraction of borides in the starting powders, whereas cubic FCC phase increased with increased carbide in the starting powders. SPS consolidated (Ti₀.₂₅V₀.₂₅Zr₀.₂₅Hf₀.₂₅)BC0.5 and (Ti₀.₂₅V₀.₂₅Zr₀.₂₅Hf₀.₂₅)B1.5C0.25 had respectively 94.74% and 88.56% relative density. (Ti₀.₂₅V₀.₂₅Zr₀.₂₅Hf₀.₂₅)B0.5C0.75 presented the highest relative density of 95.99%, with Vickers hardness of 26.58±1.2 GPa for the borides phase and 18.29±0.8 GPa for the carbides phase, which exceeded the reported hardness values reported in the literature for high entropy ceramics. The SPS sintered specimens containing lower boron and higher carbon presented superior properties even though the metallic composition in each phase was similar to other compositions investigated. Dual-phase high entropy (Ti₀.₂₅V₀.₂₅Zr₀.₂₅H₀.₂₅)BxCy ceramics were successfully fabricated in a boride-carbide solid solution and the amount of boron and carbon was shown to influence the phase fraction, hardness of phases, and density of the consolidated HECs. The microstructure and phase formation was highly dependent on the amount of non-metallic elements in the composition and not only the molar ratio between metals when producing high entropy ceramics with more than one anion in the sublattice. These findings show the importance of further studies about the optimization of the ratio between C and B for further improvements in the properties of dual-phase high entropy ceramics.

Keywords: high-entropy ceramics, borides, carbides, dual-phase

Procedia PDF Downloads 140
287 Modeling of Turbulent Flow for Two-Dimensional Backward-Facing Step Flow

Authors: Alex Fedoseyev

Abstract:

This study investigates a generalized hydrodynamic equation (GHE) simplified model for the simulation of turbulent flow over a two-dimensional backward-facing step (BFS) at Reynolds number Re=132000. The GHE were derived from the generalized Boltzmann equation (GBE). GBE was obtained by first principles from the chain of Bogolubov kinetic equations and considers particles of finite dimensions. The GHE has additional terms, temporal and spatial fluctuations, compared to the Navier-Stokes equations (NSE). These terms have a timescale multiplier τ, and the GHE becomes the NSE when $\tau$ is zero. The nondimensional τ is a product of the Reynolds number and the squared length scale ratio, τ=Re*(l/L)², where l is the apparent Kolmogorov length scale, and L is a hydrodynamic length scale. The BFS flow modeling results obtained by 2D calculations cannot match the experimental data for Re>450. One or two additional equations are required for the turbulence model to be added to the NSE, which typically has two to five parameters to be tuned for specific problems. It is shown that the GHE does not require an additional turbulence model, whereas the turbulent velocity results are in good agreement with the experimental results. A review of several studies on the simulation of flow over the BFS from 1980 to 2023 is provided. Most of these studies used different turbulence models when Re>1000. In this study, the 2D turbulent flow over a BFS with height H=L/3 (where L is the channel height) at Reynolds number Re=132000 was investigated using numerical solutions of the GHE (by a finite-element method) and compared to the solutions from the Navier-Stokes equations, k–ε turbulence model, and experimental results. The comparison included the velocity profiles at X/L=5.33 (near the end of the recirculation zone, available from the experiment), recirculation zone length, and velocity flow field. The mean velocity of NSE was obtained by averaging the solution over the number of time steps. The solution with a standard k −ε model shows a velocity profile at X/L=5.33, which has no backward flow. A standard k−ε model underpredicts the experimental recirculation zone length X/L=7.0∓0.5 by a substantial amount of 20-25%, and a more sophisticated turbulence model is needed for this problem. The obtained data confirm that the GHE results are in good agreement with the experimental results for turbulent flow over two-dimensional BFS. A turbulence model was not required in this case. The computations were stable. The solution time for the GHE is the same or less than that for the NSE and significantly less than that for the NSE with the turbulence model. The proposed approach was limited to 2D and only one Reynolds number. Further work will extend this approach to 3D flow and a higher Re.

Keywords: backward-facing step, comparison with experimental data, generalized hydrodynamic equations, separation, reattachment, turbulent flow

Procedia PDF Downloads 25
286 Inner Quality Parameters of Rapeseed (Brassica napus) Populations in Different Sowing Technology Models

Authors: É. Vincze

Abstract:

Demand on plant oils has increased to an enormous extent that is due to the change of human nutrition habits on the one hand, while on the other hand to the increase of raw material demand of some industrial sectors, just as to the increase of biofuel production. Besides the determining importance of sunflower in Hungary the production area, just as in part the average yield amount of rapeseed has increased among the produced oil crops. The variety/hybrid palette has changed significantly during the past decade. The available varieties’/hybrids’ palette has been extended to a significant extent. It is agreed that rapeseed production demands professionalism and local experience. Technological elements are successive; high yield amounts cannot be produced without system-based approach. The aim of the present work was to execute the complex study of one of the most critical production technology element of rapeseed production, that was sowing technology. Several sowing technology elements are studied in this research project that are the following: biological basis (the hybrid Arkaso is studied in this regard), sowing time (sowing time treatments were set so that they represent the wide period used in industrial practice: early, optimal and late sowing time) plant density (in this regard reaction of rare, optimal and too dense populations) were modelled. The multifactorial experimental system enables the single and complex evaluation of rapeseed sowing technology elements, just as their modelling using experimental result data. Yield quality and quantity have been determined as well in the present experiment, just as the interactions between these factors. The experiment was set up in four replications at the Látókép Plant Production Research Site of the University of Debrecen. Two different sowing times were sown in the first experimental year (2014), while three in the second (2015). Three different plant densities were set in both years: 200, 350 and 500 thousand plants ha-1. Uniform nutrient supply and a row spacing of 45 cm were applied. Winter wheat was used as pre-crop. Plant physiological measurements were executed in the populations of the Arkaso rapeseed hybrid that were: relative chlorophyll content analysis (SPAD) and leaf area index (LAI) measurement. Relative chlorophyll content (SPAD) and leaf area index (LAI) were monitored in 7 different measurement times.

Keywords: inner quality, plant density, rapeseed, sowing time

Procedia PDF Downloads 172
285 Simulation of the Visco-Elasto-Plastic Deformation Behaviour of Short Glass Fibre Reinforced Polyphthalamides

Authors: V. Keim, J. Spachtholz, J. Hammer

Abstract:

The importance of fibre reinforced plastics continually increases due to the excellent mechanical properties, low material and manufacturing costs combined with significant weight reduction. Today, components are usually designed and calculated numerically by using finite element methods (FEM) to avoid expensive laboratory tests. These programs are based on material models including material specific deformation characteristics. In this research project, material models for short glass fibre reinforced plastics are presented to simulate the visco-elasto-plastic deformation behaviour. Prior to modelling specimens of the material EMS Grivory HTV-5H1, consisting of a Polyphthalamide matrix reinforced by 50wt.-% of short glass fibres, are characterized experimentally in terms of the highly time dependent deformation behaviour of the matrix material. To minimize the experimental effort, the cyclic deformation behaviour under tensile and compressive loading (R = −1) is characterized by isothermal complex low cycle fatigue (CLCF) tests. Combining cycles under two strain amplitudes and strain rates within three orders of magnitude and relaxation intervals into one experiment the visco-elastic deformation is characterized. To identify visco-plastic deformation monotonous tensile tests either displacement controlled or strain controlled (CERT) are compared. All relevant modelling parameters for this complex superposition of simultaneously varying mechanical loadings are quantified by these experiments. Subsequently, two different material models are compared with respect to their accuracy describing the visco-elasto-plastic deformation behaviour. First, based on Chaboche an extended 12 parameter model (EVP-KV2) is used to model cyclic visco-elasto-plasticity at two time scales. The parameters of the model including a total separation of elastic and plastic deformation are obtained by computational optimization using an evolutionary algorithm based on a fitness function called genetic algorithm. Second, the 12 parameter visco-elasto-plastic material model by Launay is used. In detail, the model contains a different type of a flow function based on the definition of the visco-plastic deformation as a part of the overall deformation. The accuracy of the models is verified by corresponding experimental LCF testing.

Keywords: complex low cycle fatigue, material modelling, short glass fibre reinforced polyphthalamides, visco-elasto-plastic deformation

Procedia PDF Downloads 185
284 Use of Bamboo Piles in Ground Improvement Design: Case Study

Authors: Thayalan Nall, Andreas Putra

Abstract:

A major offshore reclamation work is currently underway in Southeast Asia for a container terminal. The total extent of the reclamation extent is 2600m x 800m and the seabed level is around -5mRL below mean sea level. Subsoil profile below seabed comprises soft marine clays of thickness varying from 8m to 15m. To contain the dredging spoil within the reclamation area, perimeter bunds have been constructed to +2.5mRL. They include breakwaters of trapezoidal geometry, made of boulder size rock along the northern, eastern and western perimeters, with a sand bund along the southern perimeter. Breakwaters were constructed on a composite bamboo pile and raft foundation system. Bamboo clusters 8m long, with 7 individual Bamboos bundled together as one, have been installed within the footprint of the breakwater below seabed in soft marine clay. To facilitate drainage two prefabricated vertical drains (PVD) have been attached to each cluster. Once the cluster piles were installed, a bamboo raft was placed as a load transfer platform. Rafts were made up of 5 layers of bamboo mattress, and in each layer bamboos were spaced at 200mm centres. The rafts wouldn’t sink under their own weight, and hence, they were sunk by loading quarry run rock onto them. Bamboo is a building material available in abundance in Indonesia and obtained at a relatively low cost. They are commonly used as semi-rigid inclusions to improve compressibility and stability of soft soils. Although bamboo is widely used in soft soil engineering design, no local design guides are available and the designs are carried out based on local experience. In June 2015, when the 1st load of sand was pumped by a dredging vessel next to the breakwater, a 150m long section of the breakwater underwent failure and displaced the breakwater between 1.2m to 4.0m. The cause of the failure was investigated to implement remedial measures to reduce the risk of further failures. Analyses using both limit equilibrium approach and finite element modelling revealed two plausible modes of breakwater failure. This paper outlines: 1) Developed Geology and the ground model, 2) The techniques used for the installation of bamboo piles, 3) Details of the analyses including modes and mechanism of failure and 4) Design changes incorporated to reduce the risk of failure.

Keywords: bamboo piles, ground improvement, reclamation, breakwater failure

Procedia PDF Downloads 371
283 The Impact of Land Use Ex-Concession to the Environment in Dharmasraya District, West Sumatra Province, Indonesia

Authors: Yurike, Yonariza, Rudi Febriamansyah, Syafruddin Karimi

Abstract:

Forest is a natural resource that has an important function as a supporting element of human life. Forest degradation enormous impact on global warming is a reality we have experienced together, that disruption of ecosystems, extreme weather conditions, disruption of water management system watersheds and the threat of natural disasters as floods, landslides and droughts, even disruption food security. Dharmasraya is a district in the province of West Sumatra, which has an area of 92.150 ha of forest, which is largely a former production forest concessions (Forest Management Rights) which is supposed to be a secondary forest. This study answers about the impact of land use in the former concession area Dharmasraya on the environment. The methodology used is the household survey, key informants, and satellite data / GIS. From the results of the study, the former concession area in Dharmasraya experienced a reduction of forest cover over time significantly. Forest concessions should be secondary forests in Dharmasraya, now turned conversion to oil palm plantations. Population pressures and growing economic pressures, resulting in more intensive harvesting. As a result of these forest disturbances caused changes in forest functions. These changes put more emphasis towards economic function by ignoring social functions or ecological function. Society prefers to maximize their benefits today and pay less attention to the protection of natural resources. This causes global warming is increasing and this is not only felt by people around Dharmasraya but also the world. Land clearing by the community through a process in slash and burn. This fire was observed by NOAA satellites and recorded by the Forest Service of West Sumatra. This demonstrates the ability of trees felled trees to absorb carbon dioxide (CO2) to be lost, even with forest fires accounted for carbon dioxide emitted into the air, and this has an impact on global warming. In addition to the change of control of land into oil palm plantations water service has been poor, people began to trouble the water and oil palm plantations are located in the watershed caused the river dried up. Through the findings of this study is expected to contribute ideas to the policy makers to pay more attention to the former concession forest management as the prevention or reduction of global warming.

Keywords: climate change, community, concession forests, environment

Procedia PDF Downloads 299
282 Model-Based Diagnostics of Multiple Tooth Cracks in Spur Gears

Authors: Ahmed Saeed Mohamed, Sadok Sassi, Mohammad Roshun Paurobally

Abstract:

Gears are important machine components that are widely used to transmit power and change speed in many rotating machines. Any breakdown of these vital components may cause severe disturbance to production and incur heavy financial losses. One of the most common causes of gear failure is the tooth fatigue crack. Early detection of teeth cracks is still a challenging task for engineers and maintenance personnel. So far, to analyze the vibration behavior of gears, different approaches have been tried based on theoretical developments, numerical simulations, or experimental investigations. The objective of this study was to develop a numerical model that could be used to simulate the effect of teeth cracks on the resulting vibrations and hence to permit early fault detection for gear transmission systems. Unlike the majority of published papers, where only one single crack has been considered, this work is more realistic, since it incorporates the possibility of multiple simultaneous cracks with different lengths. As cracks significantly alter the gear mesh stiffness, we performed a finite element analysis using SolidWorks software to determine the stiffness variation with respect to the angular position for different combinations of crack lengths. A simplified six degrees of freedom non-linear lumped parameter model of a one-stage gear system is proposed to study the vibration of a pair of spur gears, with and without tooth cracks. The model takes several physical properties into account, including variable gear mesh stiffness and the effect of friction, but ignores the lubrication effect. The vibration simulation results of the gearbox were obtained via Matlab and Simulink. The results were found to be consistent with the results from previously published works. The effect of one crack with different levels was studied and very similar changes in the total mesh stiffness and the vibration response, both were observed and compared to what has been found in previous studies. The effect of the crack length on various statistical time domain parameters was considered and the results show that these parameters were not equally sensitive to the crack percentage. Multiple cracks are introduced at different locations and the vibration response and the statistical parameters were obtained.

Keywords: dynamic simulation, gear mesh stiffness, simultaneous tooth cracks, spur gear, vibration-based fault detection

Procedia PDF Downloads 184
281 The Impact of the Variation of Sky View Factor on Landscape Degree of Enclosure of Urban Blue and Green Belt

Authors: Yi-Chun Huang, Kuan-Yun Chen, Chuang-Hung Lin

Abstract:

Urban Green Belt and Blue is a part of the city landscape, it is an important constituent element of the urban environment and appearance. The Hsinchu East Gate Moat is situated in the center of the city, which not only has a wealth of historical and cultural resources, but also combines the Green Belt and the Blue Belt qualities at the same time. The Moat runs more than a thousand meters through the vital Green Belt and the Blue Belt in downtown, and each section is presented in different qualities of moat from south to north. The water area and the green belt of surroundings are presented linear and banded spread. The water body and the rich diverse river banks form an urban green belt of rich layers. The watercourse with green belt design lets users have connections with blue belts in different ways; therefore, the integration of Hsinchu East Gate and moat have become one of the unique urban landscapes in Taiwan. The study is based on the fact-finding case of Hsinchu East Gate Moat where situated in northern Taiwan, to research the impact between the SVF variation of the city and spatial sequence of Urban Green Belt and Blue landscape and visual analysis by constituent cross-section, and then comparing the influence of different leaf area index – the variable ecological factors to the degree of enclosure. We proceed to survey the landscape design of open space, to measure existing structural features of the plant canopy which contain the height of plants and branches, the crown diameter, breast-height diameter through access to diagram of Geographic Information Systems (GIS) and on-the-spot actual measurement. The north and south districts of blue green belt areas are divided 20 meters into a unit from East Gate Roundabout as the epicenter, and to set up a survey points to measure the SVF above the survey points; then we proceed to quantitative analysis from the data to calculate open landscape degree of enclosure. The results can be reference for the composition of future river landscape and the practical operation for dynamic space planning of blue and green belt landscape.

Keywords: sky view factor, degree of enclosure, spatial sequence, leaf area indices

Procedia PDF Downloads 527
280 Winkler Springs for Embedded Beams Subjected to S-Waves

Authors: Franco Primo Soffietti, Diego Fernando Turello, Federico Pinto

Abstract:

Shear waves that propagate through the ground impose deformations that must be taken into account in the design and assessment of buried longitudinal structures such as tunnels, pipelines, and piles. Conventional engineering approaches for seismic evaluation often rely on a Euler-Bernoulli beam models supported by a Winkler foundation. This approach, however, falls short in capturing the distortions induced when the structure is subjected to shear waves. To overcome these limitations, in the present work an analytical solution is proposed considering a Timoshenko beam and including transverse and rotational springs. The present research proposes ground springs derived as closed-form analytical solutions of the equations of elasticity including the seismic wavelength. These proposed springs extend the applicability of previous plane-strain models. By considering variations in displacements along the longitudinal direction, the presented approach ensures the springs do not approach zero at low frequencies. This characteristic makes them suitable for assessing pseudo-static cases, which typically govern structural forces in kinematic interaction analyses. The results obtained, validated against existing literature and a 3D Finite Element model, reveal several key insights: i) the cutoff frequency significantly influences transverse and rotational springs; ii) neglecting displacement variations along the structure axis (i.e., assuming plane-strain deformation) results in unrealistically low transverse springs, particularly for wavelengths shorter than the structure length; iii) disregarding lateral displacement components in rotational springs and neglecting variations along the structure axis leads to inaccurately low spring values, misrepresenting interaction phenomena; iv) transverse springs exhibit a notable drop in resonance frequency, followed by increasing damping as frequency rises; v) rotational springs show minor frequency-dependent variations, with radiation damping occurring beyond resonance frequencies, starting from negative values. This comprehensive analysis sheds light on the complex behavior of embedded longitudinal structures when subjected to shear waves and provides valuable insights for the seismic assessment.

Keywords: shear waves, Timoshenko beams, Winkler springs, sol-structure interaction

Procedia PDF Downloads 38
279 How Does Spirituality Manifest in the Lives of Jordanian Patients in End Stage Renal Failure: A Phenomenological Study

Authors: A. Tamimi, S. Greatrex-White, A. Narayanasamy

Abstract:

Background: Spirituality has been increasingly acknowledged in the nursing literature as an important element of holistic patient care. To date there have been numerous studies investigating the meaning of spirituality in Western cultures. Spirituality in Middle Eastern countries however remains under-researched. We will present a study which aimed to address this gap. Aim: The study aimed to explore how spirituality manifests in the lives of Jordanian End Stage Renal Failure (ESRF) patients. Methodology and Method: A hermeneutic phenomenological approach was adopted informed by the philosophy of Martin Heidegger. Participants (n=27) were recruited from four different dialysis units: in a public hospital, a private hospital, an educational hospital and a refugee’s hospital in Jordan. Data was collected through in-depth unstructured interviews. Data Analysis: Analysis was guided by the tenets of hermeneutic phenomenology namely: gaining immediate sense of what was said both during and after each interview, transcribing data verbatim, translating interviews into the English language, intensive reading and re-reading, seeking meaning units by line to line coding, developing situated structures (how spirituality was manifest in each text), developing a general structure from the individual situated structures (how the phenomenon ‘spirituality’ comes into being). Findings: Three major themes emerged from analysis: Religion, Relationships and Desperation. We will argue that a ‘secular’ concept of spirituality had no meaning for the participants in the study. Spirituality is fundamentally part of religion and vice versa. Discussion: The findings may have consequences for the use of spirituality in multi-cultural settings in Western countries. Additionally, findings highlighted an important emphasis on the practice of spirituality, often underestimated in previous literature for Arab-Muslim Jordanian patients. Conclusion: The study findings contribute to the existing gap in knowledge regarding how Arab-Muslim Jordanian ESRF patients experience spirituality during their illness. It provides valuable insights into the importance of spirituality for this patient group and suggests how nurses, educators and policy makers might help address ESRF patients’ spiritual needs and provide appropriate spiritual care. We suggest the findings may have relevance beyond the Jordanian context in educating nurses’ on the importance of appreciating the religious dimension of spirituality.

Keywords: spirituality, nursing, muslim, Jordan

Procedia PDF Downloads 414
278 The Importance of the Phases of Information, Diagnosis, Planning, Intervention and Management in a Historic Center

Authors: Giovanni Duran Polo

Abstract:

Demonstrate the importance of the stages such as Information, Diagnosis, Management, and Intervention is fundamental to have a historical, live, and quality inhabited center. One of the major actions to take is to promote the concept of the management of a historic center with harmonious development. For that, concerned actors should strengthen the concept that said historic center may be the neighborhood of all and for all. The centers of historical cities, presented as any other urban area, social, environmental issues etc; yet they get added value that have no other city neighborhoods. The equity component, either by the urban plan, or environmental quality offered properties of architectural, landscape or some land uses are the differentiating element, while the tool that makes them attractive face pressure exerted by new housing developments or shopping centers. That's why through the experience of working in historical centers, they are declared the actions in heritage areas. This paper will show how the encounter with each of these places are trying to take the phases of information, to gather all the data needed to be closer to the territory with specific data, diagnosis; which allowed the actors to see what state they were, felt how the heart is related to the rest of the city, show what problems affected the situation and what potential it had to compete in a global market. Also, to discuss the importance of the organization, as it is legal and normative basis for it have an order and a concept, when you know what can and what cannot, in an area where the citizen has many myth or history, when he wanted to intervene in protected buildings. It is also appropriate to show how it could develop the intervention phase, where the shares on the tangible elements and intervention for the protection of the heritage property are executed. The management is the final phase which will carry out all that was raised on paper, it's time to orient, explain, persuade, promote, and encourage citizens to take care of the heritage. It is profitable and also an obligation and it is not an insurmountable burden. It has to be said this is the time to pull all the cards to make the historical center and heritage becoming more alive today. It is the moment to make it more inhabited and to transformer it into a quality place, so citizens will cherish and understand the importance of such a place. Inhabited historical centers, endowments and equipment required, with trade quality, with constant cultural offer, with well-preserved buildings and tidy, modern and safe public spaces are always attractive for tourism, but first of all, the place should be conceived for citizens, otherwise everything will be doomed to failure.

Keywords: development, diagnosis, heritage historic center, intervention, management, patrimony

Procedia PDF Downloads 376
277 The Interaction of Climate Change and Human Health in Italy

Authors: Vito Telesca, Giuseppina A. Giorgio, M. Ragosta

Abstract:

The effects of extreme heat events are increasing in recent years. Humans are forced to adjust themselves to adverse climatic conditions. The impact of weather on human health has become public health significance, especially in light of climate change and rising frequency of devasting weather events (e.g., heat waves and floods). The interest of scientific community is widely known. In particular, the associations between temperature and mortality are well studied. Weather conditions are natural factors that affect the human organism. Recent works show that the temperature threshold at which an impact is seen varies by geographic area and season. These results suggest heat warning criteria should consider local thresholds to account for acclimation to local climatology as well as the seasonal timing of a forecasted heat wave. Therefore, it is very important the problem called ‘local warming’. This is preventable with adequate warning tools and effective emergency planning. Since climate change has the potential to increase the frequency of these types of events, improved heat warning systems are urgently needed. This would require a better knowledge of the full impact of extreme heat on morbidity and mortality. The majority of researchers who analyze the associations between human health and weather variables, investigate the effect of air temperature and bioclimatic indices. These indices combine air temperature, relative humidity, and wind speed and are very important to determine the human thermal comfort. Health impact studies of weather events showed that the prevention is an essential element to dramatically reduce the impact of heat waves. The summer Italian of 2012 was characterized with high average temperatures (con un +2.3°C in reference to the period 1971-2000), enough to be considered as the second hottest summer since 1800. Italy was the first among countries in Europe which adopted tools for to predict these phenomena with 72 hours in advance (Heat Health Watch Warning System - HHWWS). Furthermore, in Italy heat alert criteria relies on the different Indexes, for example Apparent temperature, Scharlau index, Thermohygrometric Index, etc. This study examines the importance of developing public health policies that protect the most vulnerable people (such as the elderly) to extreme temperatures, highlighting the factors that confer susceptibility.

Keywords: heat waves, Italy, local warming, temperature

Procedia PDF Downloads 215