Search results for: equilibrium beach orientation
Commenced in January 2007
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Paper Count: 2041

Search results for: equilibrium beach orientation

391 Spatiotemporal Evaluation of Climate Bulk Materials Production in Atmospheric Aerosol Loading

Authors: Mehri Sadat Alavinasab Ashgezari, Gholam Reza Nabi Bidhendi, Fatemeh Sadat Alavinasab Ashkezari

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Atmospheric aerosol loading (AAL) from anthropogenic sources is an evidence in industrial development. The accelerated trends in material consumption at the global scale in recent years demonstrate consumption paradigms sensible to the planetary boundaries (PB). This paper is a statistical approach on recognizing the path of climate-relevant bulk materials production (CBMP) of steel, cement and plastics to AAL via an updated and validated spatiotemporal distribution. The methodology of statistical analysis used the most updated regional or global databases or instrumental technologies. This corresponded to a selection of processes and areas capable for tracking AAL within the last decade, analyzing the most validated data while leading to explore the behavior functions or models. The results also represented a correlation within socio economic metabolism idea between the materials specified as macronutrients of society and AAL as a PB with an unknown threshold. The selected country contributors of China, India, US and the sample country of Iran show comparable cumulative AAL values vs to the bulk materials domestic extraction and production rate in the study period of 2012 to 2022. Generally, there is a tendency towards gradual descend in the worldwide and regional aerosol concentration after 2015. As of our evaluation, a considerable share of human role, equivalent 20% from CBMP, is for the main anthropogenic species of aerosols, including sulfate, black carbon and organic particulate matters too. This study, in an innovative approach, also explores the potential role of AAL control mechanisms from the economy sectors where ordered and smoothing loading trends are accredited through the disordered phenomena of CBMP and aerosol precursor emissions. The equilibrium states envisioned is an approval to the well-established theory of Spin Glasses applicable in physical system like the Earth and here to AAL.

Keywords: atmospheric aeroso loading, material flows, climate bulk materials, industrial ecology

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390 Understanding the First Mental Breakdown from the Families’ Perspective Through Metaphors

Authors: Eli Buchbinder

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Introduction. Language is the basis to our experience as human being. We use language in describing our experiences and construct meaning and narratives from experiences. Metaphors are a valuable linguistic tool commonly use. Metaphors link two domains that are ordinarily not related. Metaphors achieve simultaneously multi-level integration: abstract and concrete, rational and imaginative, familiar and the unfamiliar, conscious and preconscious/unconscious. As such, metaphors epistemological and ontological tool that are important in social work in every field and domain. Goals and Methods The presentation’s aim is to validate the value of metaphors through the first psychiatric breakdown is a traumatic for families. The presentation is based on two pooled qualitative studies. The first study focused on 12 spouses: 7 women and 5 men, between the ages of 22 and 57, regarding their experiences and meanings of the first psychiatric hospitalization of their partners diagnosed with affective disorders. The second study focused on 10 parents, between the ages of 47 and 62, regarding their experiences and meanings following their child's first psychotic breakdown during young adulthood. Results Two types of major metaphors evolved from the interviews in farming the trauma of the first mental breakdown. The first mode - orientation (spatial) metaphors, reflect symbolic expression of the loss of a secure base, represented in the physical environment, e.g., describing hospitalization as "falling into an abyss." The second mode- ontological metaphors, reflect how parents and spouses present their traumatic experiences of hospitalization in terms of discrete, powerful and coherent entities, e.g., describing the first hospitalization as "swimming against the tide." The two metaphors modes reflect the embodiment of the unpredictability, being mired in distress, shock, intense pain and the experience the collapse of continuity on the life course and cuts off the experience of control. Conclusions Metaphors are important and powerful guide in assessing individuals and families’ phenomenological reality. As such, metaphors are useful for understanding and orientated therapeutic intervening, in the studies above, with the first psychiatric hospitalization experienced, as well as in others social workers’ interventions.

Keywords: first mental breakdown, metaphors, family perspective, qualitative research

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389 The Impacts of an Adapted Literature Circle Model on Reading Comprehension, Engagement, and Cooperation in an EFL Reading Course

Authors: Tiantian Feng

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There is a dearth of research on the literary circle as a teaching strategy in English as a Foreign Language (EFL) classes in Chinese colleges and universities and even fewer empirical studies on its impacts. In this one-quarter, design-based project, the researcher aims to increase students’ engagement, cooperation, and, on top of that, reading comprehension performance by utilizing a researcher-developed, adapted reading circle model in an EFL reading course at a Chinese college. The model also integrated team-based learning and portfolio assessment, with an emphasis on the specialization of individual responsibilities, contributions, and outcomes in reading projects, with the goal of addressing current issues in EFL classes at Chinese colleges, such as passive learning, test orientation, ineffective and uncooperative teamwork, and lack of dynamics. In this quasi-experimental research, two groups of students enrolled in the course were invited to participate in four in-class team projects, with the intervention class following the adapted literature circle model and team members rotating as Leader, Coordinator, Brain trust, and Reporter. The researcher/instructor used a sequential explanatory mixed-methods approach to quantitatively analyze the final grades for the pre-and post-tests, as well as individual scores for team projects and will code students' artifacts in the next step, with the results to be reported in a subsequent paper(s). Initial analysis showed that both groups saw an increase in final grades, but the intervention group enjoyed a more significant boost, suggesting that the adapted reading circle model is effective in improving students’ reading comprehension performance. This research not only closes the empirical research gap of literature circles in college EFL classes in China but also adds to the pool of effective ways to optimize reading comprehension performance and class performance in college EFL classes.

Keywords: literature circle, EFL teaching, college english reading, reading comprehension

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388 A Systematic Review with Meta-Analyses Investigating the Association between Binge Eating and Poor Weight Loss Outcomes in People with Obesity

Authors: Isabella Lobo Sasaoka, Felipe Q. da Luz, Zubeyir Salis, Phillipa Hay, Tamiris Gaeta, Paula Costa Teixeira, Táki Cordás, Amanda Sainsbury

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Background: A significant number of people with obesity that seek weight loss treatments experience binge eating episodes. Nonetheless, it is unknown whether binge eating episodes can hinder weight loss outcomes. Objective: To compare weight change in people with or without binge eating submitted to bariatric surgery, pharmacotherapy, nutritional orientation, and/or psychological therapies. Method: We conducted a systematic review with meta-analyses by searching studies in PubMed, American Psychological Association (APA), and Embase. Results: Thirty-four studies were included in our systematic review, and 17 studies were included in the meta-analyses. Overall, we found no significant difference in weight loss between people with or without binge eating submitted to any type of weight loss treatment. Additionally, we found no statistically significant differences in body weight between people with or without binge eating at short and long follow-up assessments following any type of weight loss treatment. We also examined changes in body weight in people with or without binge eating in three additional meta-analyses categorized by the type of weight loss treatment (i.e., behavioural and/or nutritional interventions; bariatric surgery; pharmacotherapy isolated or combined with behavior interventions) and found no difference in weight loss. Eleven out of the 17 studies that were assessed qualitatively (i.e., not included in meta-analyses) did not show differences in weight loss in people with or without binge eating submitted to any type of weight loss treatment. Conclusion: This systematic review with meta-analyses showed no difference in weight loss in people with or without binge eating submitted to a variety of weight loss treatments. Nonetheless, specialized therapies can be required to address eating disorder psychopathology and recurrent binge eating in people with obesity that seek weight loss.

Keywords: obesity, binge eating, weight loss, systematic review, meta-analysis

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387 Evaluation of Flexural Cracking Width of Steel Fibre Reinforced Concrete Beams

Authors: Touhami Tahenni

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Excessively wide cracks are harmful to the serviceability of reinforced concrete (RC) beams and may lead to durability problems in the longer term. They also reduce the rigidity of RC sections, rendering the tensile concrete ineffective structurally. To reduce the negative effects of cracks, steel fibers are added to concrete mixes in the same manner as aggregates. In the present work, steel fibers reinforced concrete (SFRC) beams, made of normal strength and high strength concretes, were tested in a four-point bending test using a digital image correlation technique. The beams had different volume fractions of fibres and different aspect ratios (fiber length/fiber diameter). The evaluation of flexural cracking widths was determined using Gom-Aramis software. The experimental crack widths were compared with theoretical values predicted by the technical document of Rilem TC 162-TDF. The model proposed in this document seems to be the only one that considers the efficiency of steel fibres in restraining the crack widths. However, the model of Rilem takes into account only the aspect ratio of steel fibres to predict the crack width of SFRC beams. It has been reported in several pieces of research that the contribution of steel fibres to the limitation of flexural cracking widths is based on three essential parameters namely, the volume fraction, the orientation and the aspect ratio of fibres. Referring to the literature on the flexural cracking behavior of SFRC beams and the experimental observations of the present work, a correction of the Rilem model by the introduction of these parameters in the formula is proposed. The crack widths predicted by the new empirical model were compared with the experimental results and assessed against other test data on SFRC beams taken from the literature. The modified Rilem model gives better results and is found more satisfactory in predicting the crack widths of fibres concrete.

Keywords: stee fibres, reinforced concrete, flexural cracking, tensile strength, crack width

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386 De Novo Design of Functional Metalloproteins for Biocatalytic Reactions

Authors: Ketaki D. Belsare, Nicholas F. Polizzi, Lior Shtayer, William F. DeGrado

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Nature utilizes metalloproteins to perform chemical transformations with activities and selectivities that have long been the inspiration for design principles in synthetic and biological systems. The chemical reactivities of metalloproteins are directly linked to local environment effects produced by the protein matrix around the metal cofactor. A complete understanding of how the protein matrix provides these interactions would allow for the design of functional metalloproteins. The de novo computational design of proteins have been successfully used in design of active sites that bind metals like di-iron, zinc, copper containing cofactors; however, precisely designing active sites that can bind small molecule ligands (e.g., substrates) along with metal cofactors is still a challenge in the field. The de novo computational design of a functional metalloprotein that contains a purposefully designed substrate binding site would allow for precise control of chemical function and reactivity. Our research strategy seeks to elucidate the design features necessary to bind the cofactor protoporphyrin IX (hemin) in close proximity to a substrate binding pocket in a four helix bundle. First- and second-shell interactions are computationally designed to control orientation, electronic structure, and reaction pathway of the cofactor and substrate. The design began with a parameterized helical backbone that positioned a single histidine residue (as an axial ligand) to receive a second-shell H-bond from a Threonine on the neighboring helix. The metallo-cofactor, hemin was then manually placed in the binding site. A structural feature, pi-bulge was introduced to give substrate access to the protoporphyrin IX. These de novo metalloproteins are currently being tested for their activity towards hydroxylation and epoxidation. The de novo designed protein shows hydroxylation of aniline to 4-aminophenol. This study will help provide structural information of utmost importance in understanding de novo computational design variables impacting the functional activities of a protein.

Keywords: metalloproteins, protein design, de novo protein, biocatalysis

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385 Advanced Electron Microscopy Study of Fission Products in a TRISO Coated Particle Neutron Irradiated to 3.6 X 1021 N/cm² Fast Fluence at 1040 ⁰C

Authors: Haiming Wen, Isabella J. Van Rooyen

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Tristructural isotropic (TRISO)-coated fuel particles are designed as nuclear fuel for high-temperature gas reactors. TRISO coating consists of layers of carbon buffer, inner pyrolytic carbon (IPyC), SiC, and outer pyrolytic carbon. The TRISO coating, especially the SiC layer, acts as a containment system for fission products produced in the kernel. However, release of certain metallic fission products across intact TRISO coatings has been observed for decades. Despite numerous studies, mechanisms by which fission products migrate across the coating layers remain poorly understood. In this study, scanning transmission electron microscopy (STEM), energy dispersive X-ray spectroscopy (EDS), high-resolution transmission electron microscopy (HRTEM) and electron energy loss spectroscopy (EELS) were used to examine the distribution, composition and structure of fission products in a TRISO coated particle neutron irradiated to 3.6 x 1021 n/cm² fast fluence at 1040 ⁰C. Precession electron diffraction was used to investigate characters of grain boundaries where specific fission product precipitates are located. The retention fraction of 110mAg in the investigated TRISO particle was estimated to be 0.19. A high density of nanoscale fission product precipitates was observed in the SiC layer close to the SiC-IPyC interface, most of which are rich in Pd, while Ag was not identified. Some Pd-rich precipitates contain U. Precipitates tend to have complex structure and composition. Although a precipitate appears to have uniform contrast in STEM, EDS indicated that there may be composition variations throughout the precipitate, and HRTEM suggested that the precipitate may have several parts different in crystal structure or orientation. Attempts were made to measure charge states of precipitates using EELS and study their possible effect on precipitate transport.

Keywords: TRISO particle, fission product, nuclear fuel, electron microscopy, neutron irradiation

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384 The Modern Era in the Cricket World: How Far Have We Really Come?

Authors: Habib Noorbhai

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History of Cricket: Cricket has a known history spanning from the 16th century till present, with international matches having been played since 1844. The game of cricket arrived in Australia as soon as colonization began in 1788. Cricketers started playing on turf wickets in the late 1800’s and dimensions for both the boundary and pitch later became assimilated. As the years evolved, cricket bats and balls, protective equipment, playing surfaces and the three formats of the game adapted to the playing conditions and laws of cricket. Business of Cricket: During the late 1900's, the shorter version of the game (T20) was introduced in order to attract the crowds to stadiums and television viewers for broadcasting rights. One could argue if this was merely a business venture or a platform for enhancing the performance of cricketers. Between the 16th and 20th century, cricket was a common sport played for passion and pure enjoyment. Industries saw a potential in diversified business ventures in the game (as well as other sports played globally) and cricket subsequently became a career for players, administrators and coaches, the media, health professionals, managers and the corporate world. Pros and Cons of Cricket Developments: At present, the game has significantly gained from the use of technology, sports sciences and varied mechanisms to optimize the performances and forecast frameworks for injury prevention in cricket players. Unfortunately, these had not been utilized in the earlier times of cricket and it would prove interesting to observe how the greats of the game would have benefited with such developments. Cricketers in the 21st century are faced with many overwhelming commitments. One of these is playing cricket for 11 months in a year, making it more than 250 days away from home and their families. As the demand of player contracts increase, the supply of commitment and performances from players increase. Way Forward and Future Implications: The questions are: Are such disadvantages contributing to the overload and injury risks of players? How far have we really come in the cricketing world or has everything since the game’s inception become institutionalized with a business model? These are the fundamental questions which need to be addressed and legislation, policies and ethical considerations need to be drafted and implemented. These will ensure that there is equilibrium of effective transitions and management of not only the players, but also the credibility of the wonderful game.

Keywords: enterprising business of cricket, technology, legislation, credibility

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383 Domestic Violence in Haryana: A Grassroot Picture of Justice System

Authors: Vandana Dave, Neelam Kumari

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India, a fast growing global power, is climbing the ladder of success very swiftly and has been attracting the world’s attention in recent decades. But unfortunately in the modern society, women who constitute half the population of our country have been the victims of violence in different fields of life both physically, socially, mentally and economically. Women face a lot of societal pressure, gender based violence – including rape, domestic violence, dowry death, murder and sexual abuse. But none the less, it is not considered as a problem of serious concern. Among the issues related to women, domestic violence is one of the major issue in our society which is occurring within the safe confines of home at the hands of close family members and cuts across line of race, nationality, language, culture, economics, sexual orientation, physical ability and religion to affect women from all walks of life. It is not to be perceived as a law and order problem alone but it is a socio- cultural problem and it is directly affecting the family life, health of women and life of children. Structural imbalance of power, systematic gender based discrimination; inequality between women and men and other kind of subordination are the context and cause of violence against women. Understanding it as a major problem of our society, the present study was conducted to assess the status of women of Rohtak, district of Haryana. The present study is based on primary and secondary data, adopting feminist research methodology. Case study method was incorporated during the research. It was observed that violence varied according to different age groups of women, marital status, education status, economic status and sociodemography factors. The case studies depicted the inadequate justice system for the victims of domestic violence. The study also revealed that the victims failed to understand the judiciary system and considered themselves helpless and hopeless. The study indicates the need of women friendly justice system for the upliftment of the society.

Keywords: domestic violence, women, victim, justice

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382 Fostering Positive Mindset: Grounded Theory Study of Self-Awareness in Emerging Adults

Authors: Maha Ben Salem

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The transformative aspect of emerging adulthood brings about a development of self-processes, including changes in self-esteem and personal goals. Success in this life stage entails the emotional growth necessary to navigate the demands and challenges of college life. Understanding the concept of self-awareness within this particular age group sheds light on emerging adults’ internal world and the transformative aspect of their emotional growth. Uncovering the thoughts' processes that foster or hinder self-awareness is important to the understanding of how emerging adults learn to make themselves positive or negative. However, existing research in self-awareness has explored this phenomenon mostly using quantitative research methodology or through tying an individual’s level of self-awareness to specific actions or outcomes. Little is known about the process of how college students emerging adults notice and monitor their inner thoughts and emotions. Methodology and theoretical orientation: A grounded theory study using in-depth semi-structured interview was utilized. Nine interviews have been conducted. A constructionist framework was employed to generate a theory as for how self-awareness facilitates specific patterns of thinking in emerging adults. The choice of grounded theory emanates from a lack of knowledge regarding underlying thinking procedures and internal states that emerging adult college students navigate in an attempt to make meaning out of the new academic experience and life stage. Findings: Initial data analysis generated the following categories of the theory: (a) a non-judgmental perception of negative thinking and negative emotions that allow for a better understanding of the self; (b) negative state of mind is easy to overcome when it is accepted and acknowledged; (c) knowledge of the actual and desired self-generates an intentional decision to shift to a positive mindset. Preliminary findings indicate that college academic and social environment foster a new understanding of the self that yield a change in mindset and in self-knowledge.

Keywords: college environment, emergent adults, grounded theory, positive mindset, self-awareness

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381 Nano-Plasmonic Diagnostic Sensor Using Ultraflat Single-Crystalline Au Nanoplate and Cysteine-Tagged Protein G

Authors: Hwang Ahreum, Kang Taejoon, Kim Bongsoo

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Nanosensors for high sensitive detection of diseases have been widely studied to improve the quality of life. Here, we suggest robust nano-plasmonic diagnostic sensor using cysteine tagged protein G (Cys3-protein G) and ultraflat, ultraclean and single-crystalline Au nanoplates. Protein G formed on an ultraflat Au surface provides ideal background for dense and uniform immobilization of antibodies. The Au is highly stable in diverse biochemical environment and can immobilize antibodies easily through Au-S bonding, having been widely used for various biosensing applications. Especially, atomically smooth single-crystalline Au nanomaterials synthesized using chemical vapor transport (CVT) method are very suitable to fabricate reproducible sensitive sensors. As the C-reactive protein (CRP) is a nonspecific biomarker of inflammation and infection, it can be used as a predictive or prognostic marker for various cardiovascular diseases. Cys3-protein G immobilized uniformly on the Au nanoplate enable CRP antibody (anti-CRP) to be ordered in a correct orientation, making their binding capacity be maximized for CRP detection. Immobilization condition for the Cys3-protein G and anti-CRP on the Au nanoplate is optimized visually by AFM analysis. Au nanoparticle - Au nanoplate (NPs-on-Au nanoplate) assembly fabricated from sandwich immunoassay for CRP can reduce zero-signal extremely caused by nonspecific bindings, providing a distinct surface-enhanced Raman scattering (SERS) enhancement still in 10-18 M of CRP concentration. Moreover, the NP-on-Au nanoplate sensor shows an excellent selectivity against non-target proteins with high concentration. In addition, comparing with control experiments employing a Au film fabricated by e-beam assisted deposition and linker molecule, we validate clearly contribution of the Au nanoplate for the attomolar sensitive detection of CRP. We expect that the devised platform employing the complex of single-crystalline Au nanoplates and Cys3-protein G can be applied for detection of many other cancer biomarkers.

Keywords: Au nanoplate, biomarker, diagnostic sensor, protein G, SERS

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380 Housing Price Dynamics: Comparative Study of 1980-1999 and the New Millenium

Authors: Janne Engblom, Elias Oikarinen

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The understanding of housing price dynamics is of importance to a great number of agents: to portfolio investors, banks, real estate brokers and construction companies as well as to policy makers and households. A panel dataset is one that follows a given sample of individuals over time, and thus provides multiple observations on each individual in the sample. Panel data models include a variety of fixed and random effects models which form a wide range of linear models. A special case of panel data models is dynamic in nature. A complication regarding a dynamic panel data model that includes the lagged dependent variable is endogeneity bias of estimates. Several approaches have been developed to account for this problem. In this paper, the panel models were estimated using the Common Correlated Effects estimator (CCE) of dynamic panel data which also accounts for cross-sectional dependence which is caused by common structures of the economy. In presence of cross-sectional dependence standard OLS gives biased estimates. In this study, U.S housing price dynamics were examined empirically using the dynamic CCE estimator with first-difference of housing price as the dependent and first-differences of per capita income, interest rate, housing stock and lagged price together with deviation of housing prices from their long-run equilibrium level as independents. These deviations were also estimated from the data. The aim of the analysis was to provide estimates with comparisons of estimates between 1980-1999 and 2000-2012. Based on data of 50 U.S cities over 1980-2012 differences of short-run housing price dynamics estimates were mostly significant when two time periods were compared. Significance tests of differences were provided by the model containing interaction terms of independents and time dummy variable. Residual analysis showed very low cross-sectional correlation of the model residuals compared with the standard OLS approach. This means a good fit of CCE estimator model. Estimates of the dynamic panel data model were in line with the theory of housing price dynamics. Results also suggest that dynamics of a housing market is evolving over time.

Keywords: dynamic model, panel data, cross-sectional dependence, interaction model

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379 Toxic Metal and Radiological Risk Assessment of Soil, Water and Vegetables around a Gold Mine Turned Residential Area in Mokuro Area of Ile-Ife, Osun State Nigeria: An Implications for Human Health

Authors: Grace O. Akinlade, Danjuma D. Maza, Oluwakemi O. Olawolu, Delight O. Babalola, John A. O. Oyekunle, Joshua O. Ojo

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The Mokuro area of Ile-Ife, South West Nigeria, was well known for gold mining in the past (about twenty years ago). However, the place has since been reclaimed and converted to residential area without any environmental risk assessment of the impact of the mining tailings on the environment. Soil, water, and plant samples were collected from 4 different locations around the mine-turned-residential area. Soil samples were pulverized and sieved into finer particles, while the plant samples were dried and pulverized. All the samples were digested and analyzed for As, Pb, Cd, and Zn using atomic absorption spectroscopy (AAS). From the analysis results, the hazard index (HI) was then calculated for the metals. The soil and plant samples were air dried and pulverized, then weighed, after which the samples were packed into special and properly sealed containers to prevent radon gas leakage. After the sealing, the samples were kept for 28 days to attain secular equilibrium. The concentrations of 40K, 238U, and 232Th in the samples were measured using a cesium iodide (CsI) spectrometer and URSA software. The AAS analysis showed that As, Pb, Cd (Toxic metals), and Zn (essential trace metals) are in concentrations lower than permissible limits in plants and soil samples, while the water samples had concentrations higher than permissible limits. The calculated health indices (HI) show that HI for water is >1 and that of plants and soil is <1. Gamma spectrometry result shows high levels of activity concentrations above the recommended limits for all the soil and plant samples collected from the area. Only the water samples have activity concentrations below the recommended limit. Consequently, the absorbed dose, annual effective dose, and excess lifetime cancer risk are all above the recommended safe limit for all the samples except for water samples. In conclusion, all the samples collected from the area are either contaminated with toxic metals or they pose radiological hazards to the consumers. Further detailed study is therefore recommended in order to be able to advise the residents appropriately.

Keywords: toxic metals, gamma spectrometry, Ile-Ife, radiological hazards, gold mining

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378 LTE Modelling of a DC Arc Ignition on Cold Electrodes

Authors: O. Ojeda Mena, Y. Cressault, P. Teulet, J. P. Gonnet, D. F. N. Santos, MD. Cunha, M. S. Benilov

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The assumption of plasma in local thermal equilibrium (LTE) is commonly used to perform electric arc simulations for industrial applications. This assumption allows to model the arc using a set of magneto-hydromagnetic equations that can be solved with a computational fluid dynamic code. However, the LTE description is only valid in the arc column, whereas in the regions close to the electrodes the plasma deviates from the LTE state. The importance of these near-electrode regions is non-trivial since they define the energy and current transfer between the arc and the electrodes. Therefore, any accurate modelling of the arc must include a good description of the arc-electrode phenomena. Due to the modelling complexity and computational cost of solving the near-electrode layers, a simplified description of the arc-electrode interaction was developed in a previous work to study a steady high-pressure arc discharge, where the near-electrode regions are introduced at the interface between arc and electrode as boundary conditions. The present work proposes a similar approach to simulate the arc ignition in a free-burning arc configuration following an LTE description of the plasma. To obtain the transient evolution of the arc characteristics, appropriate boundary conditions for both the near-cathode and the near-anode regions are used based on recent publications. The arc-cathode interaction is modeled using a non-linear surface heating approach considering the secondary electron emission. On the other hand, the interaction between the arc and the anode is taken into account by means of the heating voltage approach. From the numerical modelling, three main stages can be identified during the arc ignition. Initially, a glow discharge is observed, where the cold non-thermionic cathode is uniformly heated at its surface and the near-cathode voltage drop is in the order of a few hundred volts. Next, a spot with high temperature is formed at the cathode tip followed by a sudden decrease of the near-cathode voltage drop, marking the glow-to-arc discharge transition. During this stage, the LTE plasma also presents an important increase of the temperature in the region adjacent to the hot spot. Finally, the near-cathode voltage drop stabilizes at a few volts and both the electrode and plasma temperatures reach the steady solution. The results after some seconds are similar to those presented for thermionic cathodes.

Keywords: arc-electrode interaction, thermal plasmas, electric arc simulation, cold electrodes

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377 Impact of Civil Engineering and Economic Growth in the Sustainability of the Environment: Case of Albania

Authors: Rigers Dodaj

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Nowadays, the environment is a critical goal for civil engineers, human activity, construction projects, economic growth, and whole national development. Regarding the development of Albania's economy, people's living standards are increasing, and the requirements for the living environment are also increasing. Under these circumstances, environmental protection and sustainability this is the critical issue. The rising industrialization, urbanization, and energy demand affect the environment by emission of carbon dioxide gas (CO2), a significant parameter known to impact air pollution directly. Consequently, many governments and international organizations conducted policies and regulations to address environmental degradation in the pursuit of economic development, for instance in Albania, the CO2 emission calculated in metric tons per capita has increased by 23% in the last 20 years. This paper analyzes the importance of civil engineering and economic growth in the sustainability of the environment focusing on CO2 emission. The analyzed data are time series 2001 - 2020 (with annual frequency), based on official publications of the World Bank. The statistical approach with vector error correction model and time series forecasting model are used to perform the parameter’s estimations and long-run equilibrium. The research in this paper adds a new perspective to the evaluation of a sustainable environment in the context of carbon emission reduction. Also, it provides reference and technical support for the government toward green and sustainable environmental policies. In the context of low-carbon development, effectively improving carbon emission efficiency is an inevitable requirement for achieving sustainable economic and environmental protection. Also, the study reveals that civil engineering development projects impact greatly the environment in the long run, especially in areas of flooding, noise pollution, water pollution, erosion, ecological disorder, natural hazards, etc. The potential for reducing industrial carbon emissions in recent years indicates that reduction is becoming more difficult, it needs another economic growth policy and more civil engineering development, by improving the level of industrialization and promoting technological innovation in industrial low-carbonization.

Keywords: CO₂ emission, civil engineering, economic growth, environmental sustainability

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376 Numerical Analysis of CO₂ Storage as Clathrates in Depleted Natural Gas Hydrate Formation

Authors: Sheraz Ahmad, Li Yiming, Li XiangFang, Xia Wei, Zeen Chen

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Holding CO₂ at massive scale in the enclathrated solid matter called hydrate can be perceived as one of the most reliable methods for CO₂ sequestration to take greenhouse gases emission control measures and global warming preventive actions. In this study, a dynamically coupled mass and heat transfer mathematical model is developed which elaborates the unsteady behavior of CO₂ flowing into a porous medium and converting itself into hydrates. The combined numerical model solution by implicit finite difference method is explained and through coupling the mass, momentum and heat conservation relations, an integrated model can be established to analyze the CO₂ hydrate growth within P-T equilibrium conditions. CO₂ phase transition, effect of hydrate nucleation by exothermic heat release and variations of thermo-physical properties has been studied during hydrate nucleation. The results illustrate that formation pressure distribution becomes stable at the early stage of hydrate nucleation process and always remains stable afterward, but formation temperature is unable to keep stable and varies during CO₂ injection and hydrate nucleation process. Initially, the temperature drops due to cold high-pressure CO₂ injection since when the massive hydrate growth triggers and temperature increases under the influence of exothermic heat evolution. Intermittently, it surpasses the initial formation temperature before CO₂ injection initiates. The hydrate growth rate increases by increasing injection pressure in the long formation and it also expands overall hydrate covered length in the same induction period. The results also show that the injection pressure conditions and hydrate growth rate affect other parameters like CO₂ velocity, CO₂ permeability, CO₂ density, CO₂ and H₂O saturation inside the porous medium. In order to enhance the hydrate growth rate and expand hydrate covered length, the injection temperature is reduced, but it did not give satisfactory outcomes. Hence, CO₂ injection in vacated natural gas hydrate porous sediment may form hydrate under low temperature and high-pressure conditions, but it seems very challenging on a huge scale in lengthy formations.

Keywords: CO₂ hydrates, CO₂ injection, CO₂ Phase transition, CO₂ sequestration

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375 The Effect of Six-Weeks of Elastic Exercises with Reactionary Ropes on Nerve Conduction Velocity and Balance in Females with Multiple Sclerosis

Authors: Mostafa Sarabzadeh, Masoumeh Helalizadeh, Seyyed Mahmoud Hejazi

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Multiple Sclerosis is considered as diseases related to central nerve system, the chronic and progressive disease impress on sensory and motor function of people. Due to equilibrium problems in this patients that related to disorder of nerve conduction transmission from central nerve system to organs and the nature of elastic bands that can make changes in neuromuscular junctions and momentary actions, the aim of this research is evaluate elastic training effect by reactionary ropes on nerve conduction velocity (in lower and upper limb) and functional balance in female patients with Multiple Sclerosis. The study was a semi-experimental study that was performed based on pre and post-test method, The statistical community consisted of 16 women with MS in the age mean 25-40yrs, at low and intermediate levels of disease EDSS 1-4 (Expanded Disability Status Scale) that were divided randomly into elastic and control groups, so the training program of experimental group lasted six weeks, 3 sessions per week of elastic exercises with reactionary ropes. Electroneurography parameters (nerve conduction velocity- latency) of Upper and lower nerves (Median, Tibial, Sural, Peroneal) along with balance were investigated respectively by the Electroneurography system (ENG) and Timed up and go (TUG) functional test two times in before and after the training period. After that, To analyze the data were used of Dependent and Independent T-test (with sig level p<0.05). The results showed significant increase in nerve conduction velocity of Sural (p=0.001), Peroneal (p=0.01), Median (p=0.03) except Tibial and also development Latency Time of Tibial (p= 0), Peroneal (p=0), Median (p=0) except Sural. The TUG test showed significant decreases in execution time too (p=0.001). Generally, based on what the obtained data can indicate, modern training with elastic bands can contribute to enhanced nerve conduction velocity and balance in neurosis patients (MS) so lead to reduce problems, promotion of mobility and finally more life expectancy in these patients.

Keywords: balance, elastic bands, multiple sclerosis, nerve conduction, velocity

Procedia PDF Downloads 195
374 Q Slope Rock Mass Classification and Slope Stability Assessment Methodology Application in Steep Interbedded Sedimentary Rock Slopes for a Motorway Constructed North of Auckland, New Zealand

Authors: Azariah Sosa, Carlos Renedo Sanchez

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The development of a new motorway north of Auckland (New Zealand) includes steep rock cuts, from 63 up to 85 degrees, in an interbedded sandstone and siltstone rock mass of the geological unit Waitemata Group (Pakiri Formation), which shows sub-horizontal bedding planes, various sub-vertical joint sets, and a diverse weathering profile. In this kind of rock mass -that can be classified as a weak rock- the definition of the stable maximum geometry is not only governed by discontinuities and defects evident in the rock but is important to also consider the global stability of the rock slope, including (in the analysis) the rock mass characterisation, influence of the groundwater, the geological evolution, and the weathering processes. Depending on the weakness of the rock and the processes suffered, the global stability could, in fact, be a more restricting element than the potential instability of individual blocks through discontinuities. This paper discusses those elements that govern the stability of the rock slopes constructed in a rock formation with favourable bedding and distribution of discontinuities (horizontal and vertical) but with a weak behaviour in terms of global rock mass characterisation. In this context, classifications as Q-Slope and slope stability assessment methodology (SSAM) have been demonstrated as important tools which complement the assessment of the global stability together with the analytical tools related to the wedge-type failures and limit equilibrium methods. The paper focuses on the applicability of these two new empirical classifications to evaluate the slope stability in 18 already excavated rock slopes in the Pakiri formation through comparison between the predicted and observed stability issues and by reviewing the outcome of analytical methods (Rocscience slope stability software suite) compared against the expected stability determined from these rock classifications. This exercise will help validate such findings and correlations arising from the two empirical methods in order to adjust the methods to the nature of this specific kind of rock mass and provide a better understanding of the long-term stability of the slopes studied.

Keywords: Pakiri formation, Q-slope, rock slope stability, SSAM, weak rock

Procedia PDF Downloads 187
373 Synthesis of High-Pressure Performance Adsorbent from Coconut Shells Polyetheretherketone for Methane Adsorption

Authors: Umar Hayatu Sidik

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Application of liquid base petroleum fuel (petrol and diesel) for transportation fuel causes emissions of greenhouse gases (GHGs), while natural gas (NG) reduces the emissions of greenhouse gases (GHGs). At present, compression and liquefaction are the most matured technology used for transportation system. For transportation use, compression requires high pressure (200–300 bar) while liquefaction is impractical. A relatively low pressure of 30-40 bar is achievable by adsorbed natural gas (ANG) to store nearly compressed natural gas (CNG). In this study, adsorbents for high-pressure adsorption of methane (CH4) was prepared from coconut shells and polyetheretherketone (PEEK) using potassium hydroxide (KOH) and microwave-assisted activation. Design expert software version 7.1.6 was used for optimization and prediction of preparation conditions of the adsorbents for CH₄ adsorption. Effects of microwave power, activation time and quantity of PEEK on the adsorbents performance toward CH₄ adsorption was investigated. The adsorbents were characterized by Fourier transform infrared spectroscopy (FTIR), thermogravimetric (TG) and derivative thermogravimetric (DTG) and scanning electron microscopy (SEM). The ideal CH4 adsorption capacities of adsorbents were determined using volumetric method at pressures of 5, 17, and 35 bar at an ambient temperature and 5 oC respectively. Isotherm and kinetics models were used to validate the experimental results. The optimum preparation conditions were found to be 15 wt% amount of PEEK, 3 minutes activation time and 300 W microwave power. The highest CH4 uptake of 9.7045 mmol CH4 adsorbed/g adsorbent was recorded by M33P15 (300 W of microwave power, 3 min activation time and 15 wt% amount of PEEK) among the sorbents at an ambient temperature and 35 bar. The CH4 equilibrium data is well correlated with Sips, Toth, Freundlich and Langmuir. Isotherms revealed that the Sips isotherm has the best fit, while the kinetics studies revealed that the pseudo-second-order kinetic model best describes the adsorption process. In all scenarios studied, a decrease in temperature led to an increase in adsorption of both gases. The adsorbent (M33P15) maintained its stability even after seven adsorption/desorption cycles. The findings revealed the potential of coconut shell-PEEK as CH₄ adsorbents.

Keywords: adsorption, desorption, activated carbon, coconut shells, polyetheretherketone

Procedia PDF Downloads 50
372 Highway Waste Management in Zambia Policy Preparedness and Remedies: The Case of Great East Road

Authors: Floyd Misheck Mwanza, Paul Boniface Majura

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The paper looked at highways/ roadside waste generation, disposal and the consequent environmental impacts. The dramatic increase in vehicular and paved roads in the recent past in Zambia, has given rise to the indiscriminate disposal of litter that now poses a threat to health and the environment. Primary data was generated by carrying out oral interviews and field observations for holistic and in–depth assessment of the environment and the secondary data was obtained from desk review method, information on effects of roadside wastes on environment were obtained from relevant literatures. The interviews were semi structured and a purposive sampling method was adopted and analyzed descriptively. The results of the findings showed that population growth and unplanned road expansion has exceeded the expected limit in recent time with resultant poor system of roadside wastes disposal. Roadside wastes which contain both biodegradable and non-biodegradable roadside wastes are disposed at the shoulders of major highways in temporary dumpsites and are never collected by a road development agency (RDA). There is no organized highway to highway or street to street collection of the wastes in Zambia by the key organization the RDA. The study revealed that roadside disposal of roadside wastes has serious impacts on the environment. Some of these impacts include physical nuisance of the wastes to the environment, the waste dumps also serve as hideouts for rodents and snakes which are dangerous. Waste are blown around by wind making the environment filthy, most of the wastes are also been washed by overland flow during heavy downpour to block drainage channels and subsequently lead to flooding of the environment. Most of the non- biodegradable wastes contain toxic chemicals which have serious implications on the environmental sustainability and human health. The paper therefore recommends that Government/ RDA should come up with proper orientation and environmental laws should be put in place for the general public and also to provide necessary facilities and arrange for better methods of collection of wastes.

Keywords: biodegradable, disposal, environment, impacts

Procedia PDF Downloads 316
371 Milling Simulations with a 3-DOF Flexible Planar Robot

Authors: Hoai Nam Huynh, Edouard Rivière-Lorphèvre, Olivier Verlinden

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Manufacturing technologies are becoming continuously more diversified over the years. The increasing use of robots for various applications such as assembling, painting, welding has also affected the field of machining. Machining robots can deal with larger workspaces than conventional machine-tools at a lower cost and thus represent a very promising alternative for machining applications. Furthermore, their inherent structure ensures them a great flexibility of motion to reach any location on the workpiece with the desired orientation. Nevertheless, machining robots suffer from a lack of stiffness at their joints restricting their use to applications involving low cutting forces especially finishing operations. Vibratory instabilities may also happen while machining and deteriorate the precision leading to scrap parts. Some researchers are therefore concerned with the identification of optimal parameters in robotic machining. This paper continues the development of a virtual robotic machining simulator in order to find optimized cutting parameters in terms of depth of cut or feed per tooth for example. The simulation environment combines an in-house milling routine (DyStaMill) achieving the computation of cutting forces and material removal with an in-house multibody library (EasyDyn) which is used to build a dynamic model of a 3-DOF planar robot with flexible links. The position of the robot end-effector submitted to milling forces is controlled through an inverse kinematics scheme while controlling the position of its joints separately. Each joint is actuated through a servomotor for which the transfer function has been computed in order to tune the corresponding controller. The output results feature the evolution of the cutting forces when the robot structure is deformable or not and the tracking errors of the end-effector. Illustrations of the resulting machined surfaces are also presented. The consideration of the links flexibility has highlighted an increase of the cutting forces magnitude. This proof of concept will aim to enrich the database of results in robotic machining for potential improvements in production.

Keywords: control, milling, multibody, robotic, simulation

Procedia PDF Downloads 228
370 A Study on Adsorption Ability of MnO2 Nanoparticles to Remove Methyl Violet Dye from Aqueous Solution

Authors: Zh. Saffari, A. Naeimi, M. S. Ekrami-Kakhki, Kh. Khandan-Barani

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The textile industries are becoming a major source of environmental contamination because an alarming amount of dye pollutants are generated during the dyeing processes. Organic dyes are one of the largest pollutants released into wastewater from textile and other industrial processes, which have shown severe impacts on human physiology. Nano-structure compounds have gained importance in this category due their anticipated high surface area and improved reactive sites. In recent years several novel adsorbents have been reported to possess great adsorption potential due to their enhanced adsorptive capacity. Nano-MnO2 has great potential applications in environment protection field and has gained importance in this category because it has a wide variety of structure with large surface area. The diverse structures, chemical properties of manganese oxides are taken advantage of in potential applications such as adsorbents, sensor catalysis and it is also used for wide catalytic applications, such as degradation of dyes. In this study, adsorption of Methyl Violet (MV) dye from aqueous solutions onto MnO2 nanoparticles (MNP) has been investigated. The surface characterization of these nano particles was examined by Particle size analysis, Scanning Electron Microscopy (SEM), Fourier Transform Infrared (FTIR) spectroscopy and X-Ray Diffraction (XRD). The effects of process parameters such as initial concentration, pH, temperature and contact duration on the adsorption capacities have been evaluated, in which pH has been found to be most effective parameter among all. The data were analyzed using the Langmuir and Freundlich for explaining the equilibrium characteristics of adsorption. And kinetic models like pseudo first- order, second-order model and Elovich equation were utilized to describe the kinetic data. The experimental data were well fitted with Langmuir adsorption isotherm model and pseudo second order kinetic model. The thermodynamic parameters, such as Free energy of adsorption (ΔG°), enthalpy change (ΔH°) and entropy change (ΔS°) were also determined and evaluated.

Keywords: MnO2 nanoparticles, adsorption, methyl violet, isotherm models, kinetic models, surface chemistry

Procedia PDF Downloads 240
369 Risk Management in Islamic Micro Finance Credit System for Poverty Alleviation from Qualitative Perspective

Authors: Liyu Adhi Kasari Sulung

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Poverty has been a major problem in Indonesia. Islamic micro finance (IMF) named Baitul Maal Wat Tamwil (Bmt) plays a prominent role to eradicate this. Indonesia as the biggest muslim country has many successful applied products such as worldwide adopt group-based lending approach, flexible financing for farmers, and gold pawning. The Problems related to these models are operation risk management and internal control system (ICS). A proper ICS will help an organization in preventing the occurrence of bad financing through detecting error and irregularities in its operation. This study aims to seek a proper risk management scheme of credit system in Bmt and internal control system’s rank for every stage. Risk management variables are obtained at the first In-Depth Interview (IDI) and Focus Group Discussion (FGD) with Shariah supervisory boards, boards of directors, and operational managers. Survey was conducted covering nationwide data; West Java, South Sulawesi, and West Nusa Tenggara. Moreover, Content analysis is employed to build the relationship among these variables. Research Findings shows that risk management Characteristics in Indonesia involves ex ante, credit process, and ex post strategies to deal with risk in credit system. Ex-ante control consists of Shariah compliance, survey, group leader reference, and islamic forming orientation. Then, credit process involves saving, collateral, joint liability, loan repayment, and credit installment controlling. Finally, ex-post control includes shariah evaluation, credit evaluation, grace period and low installment provisions. In addition, internal control order sort three stages by its priority; Credit process as first rank, then ex-post control as second, and ex ante control as the last rank.

Keywords: internal control system, islamic micro finance, poverty, risk management

Procedia PDF Downloads 383
368 Two-Dimensional Analysis and Numerical Simulation of the Navier-Stokes Equations for Principles of Turbulence around Isothermal Bodies Immersed in Incompressible Newtonian Fluids

Authors: Romulo D. C. Santos, Silvio M. A. Gama, Ramiro G. R. Camacho

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In this present paper, the thermos-fluid dynamics considering the mixed convection (natural and forced convections) and the principles of turbulence flow around complex geometries have been studied. In these applications, it was necessary to analyze the influence between the flow field and the heated immersed body with constant temperature on its surface. This paper presents a study about the Newtonian incompressible two-dimensional fluid around isothermal geometry using the immersed boundary method (IBM) with the virtual physical model (VPM). The numerical code proposed for all simulations satisfy the calculation of temperature considering Dirichlet boundary conditions. Important dimensionless numbers such as Strouhal number is calculated using the Fast Fourier Transform (FFT), Nusselt number, drag and lift coefficients, velocity and pressure. Streamlines and isothermal lines are presented for each simulation showing the flow dynamics and patterns. The Navier-Stokes and energy equations for mixed convection were discretized using the finite difference method for space and a second order Adams-Bashforth and Runge-Kuta 4th order methods for time considering the fractional step method to couple the calculation of pressure, velocity, and temperature. This work used for simulation of turbulence, the Smagorinsky, and Spalart-Allmaras models. The first model is based on the local equilibrium hypothesis for small scales and hypothesis of Boussinesq, such that the energy is injected into spectrum of the turbulence, being equal to the energy dissipated by the convective effects. The Spalart-Allmaras model, use only one transport equation for turbulent viscosity. The results were compared with numerical data, validating the effect of heat-transfer together with turbulence models. The IBM/VPM is a powerful tool to simulate flow around complex geometries. The results showed a good numerical convergence in relation the references adopted.

Keywords: immersed boundary method, mixed convection, turbulence methods, virtual physical model

Procedia PDF Downloads 95
367 Genetics, Law and Society: Regulating New Genetic Technologies

Authors: Aisling De Paor

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Scientific and technological developments are driving genetics and genetic technologies into the public sphere. Scientists are making genetic discoveries as to the make up of the human body and the cause and effect of disease, diversity and disability amongst individuals. Technological innovation in the field of genetics is also advancing, with the development of genetic testing, and other emerging genetic technologies, including gene editing (which offers the potential for genetic modification). In addition to the benefits for medicine, health care and humanity, these genetic advances raise a range of ethical, legal and societal concerns. From an ethical perspective, such advances may, for example, change the concept of humans and what it means to be human. Science may take over in conceptualising human beings, which may push the boundaries of existing human rights. New genetic technologies, particularly gene editing techniques create the potential to stigmatise disability, by highlighting disability or genetic difference as something that should be eliminated or anticipated. From a disability perspective, use (and misuse) of genetic technologies raise concerns about discrimination and violations to the dignity and integrity of the individual. With an acknowledgement of the likely future orientation of genetic science, and in consideration of the intersection of genetics and disability, this paper highlights the main concerns raised as genetic science and technology advances (particularly with gene editing developments), and the consequences for disability and human rights. Through the use of traditional doctrinal legal methodologies, it investigates the use (and potential misuse) of gene editing as creating the potential for a unique form of discrimination and stigmatization to develop, as well as a potential gateway to a form of new, subtle eugenics. This article highlights the need to maintain caution as to the use, application and the consequences of genetic technologies. With a focus on the law and policy position in Europe, it examines the need to control and regulate these new technologies, particularly gene editing. In addition to considering the need for regulation, this paper highlights non-normative approaches to address this area, including awareness raising and education, public discussion and engagement with key stakeholders in the field and the development of a multifaceted genetics advisory network.

Keywords: disability, gene-editing, genetics, law, regulation

Procedia PDF Downloads 336
366 Corporate Digital Responsibility in Construction Engineering-Construction 4.0: Ethical Guidelines for Digitization and Artificial Intelligence

Authors: Weber-Lewerenz Bianca

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Digitization is developing fast and has become a powerful tool for digital planning, construction, and operations. Its transformation bears high potentials for companies, is critical for success, and thus, requires responsible handling. This study provides an assessment of calls made in the sustainable development goals by the United Nations (SDGs), White Papers on AI by international institutions, EU-Commission and German Government requesting for the consideration and protection of values and fundamental rights, the careful demarcation between machine (artificial) and human intelligence and the careful use of such technologies. The study discusses digitization and the impacts of artificial intelligence (AI) in construction engineering from an ethical perspective by generating data via conducting case studies and interviewing experts as part of the qualitative method. This research evaluates critically opportunities and risks revolving around corporate digital responsibility (CDR) in the construction industry. To the author's knowledge, no study has set out to investigate how CDR in construction could be conceptualized, especially in relation to the digitization and AI, to mitigate digital transformation both in large, medium-sized, and small companies. No study addressed the key research question: Where can CDR be allocated, how shall its adequate ethical framework be designed to support digital innovations in order to make full use of the potentials of digitization and AI? Now is the right timing for constructive approaches and apply ethics-by-design in order to develop and implement a safe and efficient AI. This represents the first study in construction engineering applying a holistic, interdisciplinary, inclusive approach to provide guidelines for orientation, examine benefits of AI and define ethical principles as the key driver for success, resources-cost-time efficiency, and sustainability using digital technologies and AI in construction engineering to enhance digital transformation. Innovative corporate organizations starting new business models are more likely to succeed than those dominated by conservative, traditional attitudes.

Keywords: construction engineering, digitization, digital transformation, artificial intelligence, ethics, corporate digital responsibility, digital innovation

Procedia PDF Downloads 210
365 Simulation Based Analysis of Gear Dynamic Behavior in Presence of Multiple Cracks

Authors: Ahmed Saeed, Sadok Sassi, Mohammad Roshun

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Gears are important components with a vital role in many rotating machines. One of the common gear failure causes is tooth fatigue crack; however, its early detection is still a challenging task. The objective of this study is to develop a numerical model that simulates the effect of teeth cracks on the resulting gears vibrations and permits consequently to perform an early fault detection. In contrast to other published papers, this work incorporates the possibility of multiple simultaneous cracks with different depths. As cracks alter significantly the stiffness of the tooth, finite element software is used to determine the stiffness variation with respect to the angular position, for different combinations of crack orientation and depth. A simplified six degrees of freedom nonlinear lumped parameter model of a one-stage spur gear system is proposed to study the vibration with and without cracks. The model developed for calculating the stiffness with the crack permitted to update the physical parameters of the second-degree-of-freedom equations of motions describing the vibration of the gearbox. The vibration simulation results of the gearbox were by obtained using Simulink/Matlab. The effect of one crack with different levels was studied thoroughly. The change in the mesh stiffness and the vibration response were found to be consistent with previously published works. In addition, various statistical time domain parameters were considered. They showed different degrees of sensitivity toward the crack depth. Multiple cracks were also introduced at different locations and the vibration response along with the statistical parameters were obtained again for a general case of degradation (increase in crack depth, crack number and crack locations). It was found that although some parameters increase in value as the deterioration level increases, they show almost no change or even decrease when the number of cracks increases. Therefore, the use of any statistical parameters could be misleading if not considered in an appropriate way.

Keywords: Spur gear, cracked tooth, numerical simulation, time-domain parameters

Procedia PDF Downloads 249
364 Photovoltaic Solar Energy in Public Buildings: A Showcase for Society

Authors: Eliane Ferreira da Silva

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This paper aims to mobilize and sensitize public administration leaders to good practices and encourage investment in the PV system in Brazil. It presents a case study methodology for dimensioning the PV system in the roofs of the public buildings of the Esplanade of the Ministries, Brasilia, capital of the country, with predefined resources, starting with the Sustainable Esplanade Project (SEP), of the exponential growth of photovoltaic solar energy in the world and making a comparison with the solar power plant of the Ministry of Mines and Energy (MME), active since: 6/10/2016. In order to do so, it was necessary to evaluate the energy efficiency of the buildings in the period from January 2016 to April 2017, (16 months) identifying the opportunities to reduce electric energy expenses, through the adjustment of contracted demand, the tariff framework and correction of existing active energy. The instrument used to collect data on electric bills was the e-SIC citizen information system. The study considered in addition to the technical and operational aspects, the historical, cultural, architectural and climatic aspects, involved by several actors. Identifying the reductions of expenses, the study directed to the following aspects: Case 1) economic feasibility for exchanges of common lamps, for LED lamps, and, Case 2) economic feasibility for the implementation of photovoltaic solar system connected to the grid. For the case 2, PV*SOL Premium Software was used to simulate several possibilities of photovoltaic panels, analyzing the best performance, according to local characteristics, such as solar orientation, latitude, annual average solar radiation. A simulation of an ideal photovoltaic solar system was made, with due calculations of its yield, to provide a compensation of the energy expenditure of the building - or part of it - through the use of the alternative source in question. The study develops a methodology for public administration, as a major consumer of electricity, to act in a responsible, fiscalizing and incentive way in reducing energy waste, and consequently reducing greenhouse gases.

Keywords: energy efficiency, esplanade of ministries, photovoltaic solar energy, public buildings, sustainable building

Procedia PDF Downloads 111
363 Adaptation Mechanism and Planning Response to Resiliency Shrinking of Small Towns Based on Complex Adaptive System by Taking Wuhan as an Example

Authors: Yanqun Li, Hong Geng

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The rapid urbanization process taking big cities as the main body leads to the unequal configuration of urban and rural areas in the aspects of land supply, industrial division of labor, service supply and space allocation, and induces the shrinking characterization of service energy, industrial system and population vitality in small towns. As an important spatial unit in the spectrum of urbanization that serves, connects and couples urban and rural areas, the shrinking phenomenon faced by small towns has an important influence on the healthy development of urbanization. Based on the census of small towns in Wuhan metropolitan area, we have found that the shrinking of small towns is a passive contraction of elastic tension under the squeeze in cities. Once affected by the external forces such as policy regulation, planning guidance, and population return, small towns will achieve expansion and growth. Based on the theory of complex adaptive systems, this paper comprehensively constructs the development index evaluation system of small towns from five aspects of population, economy, space, society and ecology, measures the shrinking level of small towns, further analyzes the shrinking characteristics of small towns, and identifies whether the shrinking is elastic or not. And then this paper measures the resilience ability index of small town contract from the above-mentioned five aspects. Finally, this paper proposes an adaptive mechanism of urban-rural interaction evolution under fine division of labor to response the passive shrinking in small towns of Wuhan. Based on the above, the paper creatively puts forward the planning response measures of the small towns on the aspects of spatial layout, function orientation and service support, which can provide reference for other regions.

Keywords: complex adaptive systems, resiliency shrinking, adaptation mechanism, planning response

Procedia PDF Downloads 92
362 Boosting the Chance of Organizational Change Success: The Role of Individuals’ Goal Orientation, Affectivity and Psychological Capital

Authors: P. P. L. Kwan, D. K. S. Chan

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Organizations are constantly changing in today’s business environment. Research findings have revealed that overcoming resistance and getting employees ready for change is a crucial driver for organizational change success. Thus, change adaptability has become a more prominent selection criterion used in many organizations. Although change readiness could be situation-specific, employees’ personality, emotion, and cognition should also be crucial factors in shaping their readiness. However, relatively little research has focused on the roles of individual characteristics in organizational changes. The present study examines the relations between individual characteristics and change readiness with the aim to validate a model, which proposes three types of individual attributes as antecedents to change readiness. The three attributes considered are trait cynicism, positive affectivity, and personal valence covering personality, emotional, and cognitive aspects respectively. The model also hypothesizes that relations between the three antecedents and change readiness will be moderated by a positive mental resource known as psychological capital (PsyCap), which consists of hope, optimism, efficacy and resilience; and a learning culture within the organization. We are currently collecting data from a targeted sample size of 300 Hong Kong employees. Specifically, participants complete a questionnaire which was designed to measure their perceived change efficacy in response to three scenarios commonly happened in the workplace (i.e., business acquisition, team restructuring, and information system change) as a measure of change readiness, as well as the aforementioned individual characteristics. Preliminary analysis provides some support to the hypotheses. That is, employees who are less cynical in personality and more positive in their cognition and affectivity particularly welcome the potential changes in their organizations. Further data collection and analyses are continuously carried out for a more definitive conclusion. Our findings will shed light on employee selection; and on how strengthening positive psychological resources and promoting the culture of learning organization among employees may enhance the chance to succeed for organizations undergoing change.

Keywords: learning organization, psychological capital, readiness for change, employee selection

Procedia PDF Downloads 442