Search results for: role model
23827 Landscape Factors Eliciting the Sense of Relaxation in Urban Green Space
Authors: Kaowen Grace Chang
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Urban green spaces play an important role in promoting wellbeing through the sense of relaxation for urban residents. Among many designing factors, what the principal ones that could effectively influence people’s sense of relaxation? And, what are the relationship between the sense of relaxation and those factors? Regarding those questions, there is still little evidence for sufficient support. Therefore, the purpose of this study, based on individual responses to environmental information, is to investigate the landscape factors that relate to well-being through the sense of relaxation in mixed-use urban environments. We conducted the experimental design and model construction utilizing choice-based conjoint analysis to test the factors of plant arrangement pattern, plant trimming condition, the distance to visible automobile, the number of landmark objects, and the depth of view. Through the operation of balanced fractional orthogonal design, the goal is to know the relationship between the sense of relaxation and different designs. In a result, the three factors of plant trimming condition, the distance to visible automobile, and the depth of view shed are significantly effective to the sense of relaxation. The stronger magnitude of maintenance and trimming, the further distance to visible automobiles, and deeper view shed that allow the users to see further scenes could significantly promote green space users’ sense of relaxation in urban green spaces.Keywords: urban green space, landscape planning and design, sense of relaxation, choice model
Procedia PDF Downloads 14823826 Zakariya Multaniand and his Role in the Spread of Islam and Suhrawardiyya in the Subcontinent
Authors: Mahdi Momeni
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The arrival of Mysticism to the subcontinent can be generally divided into two periods. The first period, was the Sporadic arrival of Sufis whom were traveling to the subcontinent according to the tradition of disquisition and the second period was; when the Sufi dynasties were sending missionaries and caliphs to guide and promote people from different direction to that land. Among the Sufi dynasty that entered to India in the thirteenth century, two dynasties of Chishti and Suhrawardîya were more successful than other Sufi dynasties. And thus they are very important in the spread of Islam and Mysticism to the subcontinent. Suhrawardiyya dynasty was founded by Sheikh Ziauddin Abu Najib Suhrawardi and was developed and spread by his nephew Sheikh Shahabuddin Suhrawardi Abo hafs Omar. Sheikh Shahabuddin sent many Caliphs and missionaries to India. Among these missionaries were People like Sultan Sakhi Sarwar, Seyyed Noureddin Mobarak Ghaznavi, Sheikh Jalal al-din Tabrizi and Sheikh Zakariya Multani. Since Suhrawardiyya doctrine relies on Asceticism and Sharia, so one of the important elements among Suhrawardiyya missionaries was inviting people to Islam. Accordingly Sheikh Shahab Caliphs had a great role in the spread of Islam and Mysticism in different territories, especially India. Such that it can be pointed out is the the role of Sheikh Baha-ud-din Zakariya Multani, the founder of Suhrawardiyya Dynasty in India. Sheikh Zakaria Multani after working in three areas, establishing monasteries, training managers, having numerous trips to different places, participating to social affairs provided the spread of Islam and Mysticism in subcontinent. This paper studies his role and actions in the subcontinent.Keywords: islam, sufism, Suhrawardiyya, subcontinent, Multan
Procedia PDF Downloads 50623825 Optimization of Platinum Utilization by Using Stochastic Modeling of Carbon-Supported Platinum Catalyst Layer of Proton Exchange Membrane Fuel Cells
Authors: Ali Akbar, Seungho Shin, Sukkee Um
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The composition of catalyst layers (CLs) plays an important role in the overall performance and cost of the proton exchange membrane fuel cells (PEMFCs). Low platinum loading, high utilization, and more durable catalyst still remain as critical challenges for PEMFCs. In this study, a three-dimensional material network model is developed to visualize the nanostructure of carbon supported platinum Pt/C and Pt/VACNT catalysts in pursuance of maximizing the catalyst utilization. The quadruple-phase randomly generated CLs domain is formulated using quasi-random stochastic Monte Carlo-based method. This unique statistical approach of four-phase (i.e., pore, ionomer, carbon, and platinum) model is closely mimic of manufacturing process of CLs. Various CLs compositions are simulated to elucidate the effect of electrons, ions, and mass transport paths on the catalyst utilization factor. Based on simulation results, the effect of key factors such as porosity, ionomer contents and Pt weight percentage in Pt/C catalyst have been investigated at the represented elementary volume (REV) scale. The results show that the relationship between ionomer content and Pt utilization is in good agreement with existing experimental calculations. Furthermore, this model is implemented on the state-of-the-art Pt/VACNT CLs. The simulation results on Pt/VACNT based CLs show exceptionally high catalyst utilization as compared to Pt/C with different composition ratios. More importantly, this study reveals that the maximum catalyst utilization depends on the distance spacing between the carbon nanotubes for Pt/VACNT. The current simulation results are expected to be utilized in the optimization of nano-structural construction and composition of Pt/C and Pt/VACNT CLs.Keywords: catalyst layer, platinum utilization, proton exchange membrane fuel cell, stochastic modeling
Procedia PDF Downloads 12123824 Genetic Algorithm for Bi-Objective Hub Covering Problem
Authors: Abbas Mirakhorli
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A hub covering problem is a type of hub location problem that tries to maximize the coverage area with the least amount of installed hubs. There have not been many studies in the literature about multi-objective hubs covering location problems. Thus, in this paper, a bi-objective model for the hub covering problem is presented. The two objectives that are considered in this paper are the minimization of total transportation costs and the maximization of coverage of origin-destination nodes. A genetic algorithm is presented to solve the model when the number of nodes is increased. The genetic algorithm is capable of solving the model when the number of nodes increases by more than 20. Moreover, the genetic algorithm solves the model in less amount of time.Keywords: facility location, hub covering, multi-objective optimization, genetic algorithm
Procedia PDF Downloads 6023823 Metal-Based Deep Eutectic Solvents for Extractive Desulfurization of Fuels: Analysis from Molecular Dynamics Simulations
Authors: Aibek Kukpayev, Dhawal Shah
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Combustion of sour fuels containing high amount of sulfur leads to the formation of sulfur oxides, which adversely harm the environment and has a negative impact on human health. Considering this, several legislations have been imposed to bring down the sulfur content in fuel to less than 10 ppm. In recent years, novel deep eutectic solvents (DESs) have been developed to achieve deep desulfurization, particularly to extract thiophenic compounds from liquid fuels. These novel DESs, considered as analogous to ionic liquids are green, eco-friendly, inexpensive, and sustainable. We herein, using molecular dynamic simulation, analyze the interactions of metal-based DESs with model oil consisting of thiophenic compounds. The DES used consists of polyethylene glycol (PEG-200) as a hydrogen bond donor, choline chloride (ChCl) or tetrabutyl ammonium chloride (TBAC) as a hydrogen bond acceptor, and cobalt chloride (CoCl₂) as metal salt. In particular, the combination of ChCl: PEG-200:CoCl₂ at a ratio 1:2:1 and the combination of TBAC:PEG-200:CoCl₂ at a ratio 1:2:0.25 were simulated, separately, with model oil consisting of octane and thiophenes at 25ᵒC and 1 bar. The results of molecular dynamics simulations were analyzed in terms of interaction energies between different components. The simulations revealed a stronger interaction between DESs/thiophenes as compared with octane/thiophenes, suggestive of an efficient desulfurization process. In addition, our analysis suggests that the choice of hydrogen bond acceptor strongly influences the efficiency of the desulfurization process. Taken together, the results also show the importance of the metal ion, although present in small amount, in the process, and the role of the polymer in desulfurization of the model fuel.Keywords: deep eutectic solvents, desulfurization, molecular dynamics simulations, thiophenes
Procedia PDF Downloads 14623822 3D Liver Segmentation from CT Images Using a Level Set Method Based on a Shape and Intensity Distribution Prior
Authors: Nuseiba M. Altarawneh, Suhuai Luo, Brian Regan, Guijin Tang
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Liver segmentation from medical images poses more challenges than analogous segmentations of other organs. This contribution introduces a liver segmentation method from a series of computer tomography images. Overall, we present a novel method for segmenting liver by coupling density matching with shape priors. Density matching signifies a tracking method which operates via maximizing the Bhattacharyya similarity measure between the photometric distribution from an estimated image region and a model photometric distribution. Density matching controls the direction of the evolution process and slows down the evolving contour in regions with weak edges. The shape prior improves the robustness of density matching and discourages the evolving contour from exceeding liver’s boundaries at regions with weak boundaries. The model is implemented using a modified distance regularized level set (DRLS) model. The experimental results show that the method achieves a satisfactory result. By comparing with the original DRLS model, it is evident that the proposed model herein is more effective in addressing the over segmentation problem. Finally, we gauge our performance of our model against matrices comprising of accuracy, sensitivity and specificity.Keywords: Bhattacharyya distance, distance regularized level set (DRLS) model, liver segmentation, level set method
Procedia PDF Downloads 31323821 AM/E/c Queuing Hub Maximal Covering Location Model with Fuzzy Parameter
Authors: M. H. Fazel Zarandi, N. Moshahedi
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The hub location problem appears in a variety of applications such as medical centers, firefighting facilities, cargo delivery systems and telecommunication network design. The location of service centers has a strong influence on the congestion at each of them, and, consequently, on the quality of service. This paper presents a fuzzy maximal hub covering location problem (FMCHLP) in which travel costs between any pair of nodes is considered as a fuzzy variable. In order to consider the quality of service, we model each hub as a queue. Arrival rate follows Poisson distribution and service rate follows Erlang distribution. In this paper, at first, a nonlinear mathematical programming model is presented. Then, we convert it to the linear one. We solved the linear model using GAMS software up to 25 nodes and for large sizes due to the complexity of hub covering location problems, and simulated annealing algorithm is developed to solve and test the model. Also, we used possibilistic c-means clustering method in order to find an initial solution.Keywords: fuzzy modeling, location, possibilistic clustering, queuing
Procedia PDF Downloads 39423820 The Public Policy of Energy Subsidies Reform in Egypt
Authors: Doaa Nounou
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This research examines the public policy energy subsidies reform efforts in Egypt since 2014. Egypt’s widely used energy subsidies have been controversial since they were first introduced, as they inadequately target the poorest part of the population. Also, their effect on economic development and democratic transition became very challenging in recent years. This research argues that although subsidy reform is a highly politicalized issue in democratizing countries, there are still a number of pragmatic public policies that can be applied to make the subsidy system function more efficiently and at the same time decrease inequality which could facilitate a more orderly and peaceful transition to democracy. Therefore, this research attempts to study the role of the executive branch in reforming the subsidy programmes to support the poor and bring about structural changes to achieve social justice and economic growth. This research also attempts to analyze the role of the military and civil society in reforming the subsidy system. Moreover, it attempts to discuss the role of the state media in social mobilization to rationalize consumption and its contribution to subsidies reform.Keywords: subsidies, public policy, political economy, democratization, equality
Procedia PDF Downloads 21923819 The Study of Applying Models: House, Temple and School for Sufficiency Development to Participate in ASEAN Economic Community: A Case Study of Trimitra Temple (China Town) Bangkok, Thailand
Authors: Saowapa Phaithayawat
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The purposes of this study are: 1) to study the impact of the 3-community-core model: House (H), Temple (T), and School (S) with the co-operation of official departments on community development to ASEAN economic community involvement, and 2) to study the procedures and extension of the model. The research which is a qualitative research based on formal and informal interviews. Local people in a community are observed. Group interview is also operated by executors and cooperators in the school in the community. In terms of social and cultural dimension, the 3-community-core model consisting of house, temple and school is the base of Thai cultures bringing about understanding, happiness and unity to the community. The result of this research is that the official departments in accompanied with this model developers cooperatively work together in the community to support such factors as budget, plan, activities. Moreover, the need of community, and the continual result to sustain the community are satisfied by the model implementation. In terms of the procedures of the model implementation, executors and co-operators can work, coordinate, think, and launch their public relation altogether. Concerning the model development, this enables the community to achieve its goal to prepare the community’s readiness for ASEAN Economic Community involvement.Keywords: ASEAN Economic Community, the applying models and sufficiency development, house, temple, school
Procedia PDF Downloads 31423818 Cybernetic Modeling of Growth Dynamics of Debaryomyces nepalensis NCYC 3413 and Xylitol Production in Batch Reactor
Authors: J. Sharon Mano Pappu, Sathyanarayana N. Gummadi
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Growth of Debaryomyces nepalensis on mixed substrates in batch culture follows diauxic pattern of completely utilizing glucose during the first exponential growth phase, followed by an intermediate lag phase and a second exponential growth phase consuming xylose. The present study deals with the development of cybernetic mathematical model for prediction of xylitol production and yield. Production of xylitol from xylose in batch fermentation is investigated in the presence of glucose as the co-substrate. Different ratios of glucose and xylose concentrations are assessed to study the impact of multi substrate on production of xylitol in batch reactors. The parameters in the model equations were estimated from experimental observations using integral method. The model equations were solved simultaneously by numerical technique using MATLAB. The developed cybernetic model of xylose fermentation in the presence of a co-substrate can provide answers about how the ratio of glucose to xylose influences the yield and rate of production of xylitol. This model is expected to accurately predict the growth of microorganism on mixed substrate, duration of intermediate lag phase, consumption of substrate, production of xylitol. The model developed based on cybernetic modelling framework can be helpful to simulate the dynamic competition between the metabolic pathways.Keywords: co-substrate, cybernetic model, diauxic growth, xylose, xylitol
Procedia PDF Downloads 32823817 Close-Out Netting Clauses from a Comparative Perspective
Authors: Lidija Simunovic
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A Close-out netting cause is a clause within master agreements which reduces credit risks. This clause contains the parties ' advance agreement that the occurrence of a certain event (such as the commencement of bankruptcy proceedings) will result in the termination of the contract and that their mutual claims will be calculated as a net lump-sum to be paid by one party to the other. The legal treatment of the enforceability of close-out netting clauses opens up many legal matters in comparative legal systems because it is not uniformly treated in comparative laws. Certain legal systems take a liberal approach and allow the enforcement of close-out netting clauses. Others are much stricter, and they limit or completely prohibit the enforcement of close-out netting clauses through the mandatory provisions of their national bankruptcy laws. The author analyzes the concept of close-out netting clauses in selected comparative legal systems and examines the differences in their legal treatment by using the historical, analytical, and comparative method. It results that special treatment of the close-out netting in national laws with a liberal approach is often forced by financial industry lobbies and introduced in national laws without the justified reasons. Contrary to that in legal systems with limited or prohibited approach on close-out netting the uncertain enforceability of the close-out netting clause causes potential credit risks. The detected discrepancy on the national legal treatment and national financial markets regarding close-out netting lead to the conclusion to author’s best knowledge that is not possible to use any national model of close-out netting as a role model which perfectly fits all.Keywords: close-out netting clauses, derivatives, insolvency, offsetting
Procedia PDF Downloads 14523816 Numerical Investigation of Beam-Columns Subjected to Non-Proportional Loadings under Ambient Temperature Conditions
Authors: George Adomako Kumi
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The response of structural members, when subjected to various forms of non-proportional loading, plays a major role in the overall stability and integrity of a structure. This research seeks to present the outcome of a finite element investigation conducted by the use of finite element programming software ABAQUS to validate the experimental results of elastic and inelastic behavior and strength of beam-columns subjected to axial loading, biaxial bending, and torsion under ambient temperature conditions. The application of the rigorous and highly complicated ABAQUS finite element software will seek to account for material, non-linear geometry, deformations, and, more specifically, the contact behavior between the beam-columns and support surfaces. Comparisons of the three-dimensional model with the results of actual tests conducted and results from a solution algorithm developed through the use of the finite difference method will be established in order to authenticate the veracity of the developed model. The results of this research will seek to provide structural engineers with much-needed knowledge about the behavior of steel beam columns and their response to various non-proportional loading conditions under ambient temperature conditions.Keywords: beam-columns, axial loading, biaxial bending, torsion, ABAQUS, finite difference method
Procedia PDF Downloads 18023815 Participation of Juvenile with Driven of Tobacco Control in Education Institute: Case Study of Suan Sunandha Rajabhat University
Authors: Sakapas Saengchai
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This paper studied the participation of juvenile with driven of tobacco control in education institute: case study of Suan Sunandha Rajabhat University is qualitative research has objective to study participation of juvenile with driven of tobacco control in University, as guidance of development participation of juvenile with driven of tobacco control in education institute the university is also free-cigarette university. There are qualitative researches on collection data of participation observation, in-depth interview of group conversation and agent of student in each faculty and college and exchange opinion of student. Result of study found that participation in tobacco control has 3 parts; 1) Participation in campaign of tobacco control, 2) Academic training and activity of free-cigarette of university and 3) As model of juvenile in tobacco control. For guidelines on youth involvement in driven tobacco control is universities should promote tobacco control activities. Reduce smoking campaign continues include a specific area for smokers has living room as sign clearly, staying in the faculty / college and developing network of model students who are non-smoking. This is a key role in the coordination of university students driving to the free cigarette university. Including the strengthening of community in the area and outside the area as good social and quality of country.Keywords: participation, juvenile, tobacco control, institute
Procedia PDF Downloads 27323814 A Simulation Model and Parametric Study of Triple-Effect Desalination Plant
Authors: Maha BenHamad, Ali Snoussi, Ammar Ben Brahim
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A steady-state analysis of triple-effect thermal vapor compressor desalination unit was performed. A mathematical model based on mass, salinity and energy balances is developed. The purpose of this paper is to develop a connection between process simulator and process optimizer in order to study the influence of several operating variables on the performance and the produced water cost of the unit. A MATLAB program is used to solve the model equations, and Aspen HYSYS is used to model the plant. The model validity is examined against a commercial plant and showed a good agreement between industrial data and simulations results. Results show that the pressures of the last effect and the compressed vapor have an important influence on the produced cost, and the increase of the difference temperature in the condenser decreases the specific heat area about 22%.Keywords: steady-state, triple effect, thermal vapor compressor, Matlab, Aspen Hysys
Procedia PDF Downloads 17223813 Predictive Models of Ruin Probability in Retirement Withdrawal Strategies
Authors: Yuanjin Liu
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Retirement withdrawal strategies are very important to minimize the probability of ruin in retirement. The ruin probability is modeled as a function of initial withdrawal age, gender, asset allocation, inflation rate, and initial withdrawal rate. The ruin probability is obtained based on the 2019 period life table for the Social Security, IRS Required Minimum Distribution (RMD) Worksheets, US historical bond and equity returns, and inflation rates using simulation. Several popular machine learning algorithms of the generalized additive model, random forest, support vector machine, extreme gradient boosting, and artificial neural network are built. The model validation and selection are based on the test errors using hyperparameter tuning and train-test split. The optimal model is recommended for retirees to monitor the ruin probability. The optimal withdrawal strategy can be obtained based on the optimal predictive model.Keywords: ruin probability, retirement withdrawal strategies, predictive models, optimal model
Procedia PDF Downloads 7423812 The Teacher’s Role in Generating and Maintaining the Motivation of Adult Learners of English: A Mixed Methods Study in Hungarian Corporate Contexts
Authors: Csaba Kalman
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In spite of the existence of numerous second language (L2) motivation theories, the teacher’s role in motivating learners has remained an under-researched niche to this day. If we narrow down our focus on the teacher’s role on motivating adult learners of English in an English as a Foreign Language (EFL) context in corporate environments, empirical research is practically non-existent. This study fills the above research niche by exploring the most motivating aspects of the teacher’s personality, behaviour, and teaching practices that affect adult learners’ L2 motivation in corporate contexts in Hungary. The study was conducted in a wide range of industries in 18 organisations that employ over 250 people in Hungary. In order to triangulate the research, 21 human resources managers, 18 language teachers, and 466 adult learners of English were involved in the investigation by participating in interview studies, and quantitative questionnaire studies that measured ten scales related to the teacher’s role, as well as two criterion measure scales of intrinsic and extrinsic motivation. The qualitative data were analysed using a template organising style, while descriptive, inferential statistics, as well as multivariate statistical techniques, such as correlation and regression analyses, were used for analysing the quantitative data. The results showed that certain aspects of the teacher’s personality (thoroughness, enthusiasm, credibility, and flexibility), as well as preparedness, incorporating English for Specific Purposes (ESP) in the syllabus, and focusing on the present, proved to be the most salient aspects of the teacher’s motivating influence. The regression analyses conducted with the criterion measure scales revealed that 22% of the variance in learners’ intrinsic motivation could be explained by the teacher’s preparedness and appearance, and 23% of the variance in learners’ extrinsic motivation could be attributed to the teacher’s personal branding and incorporating ESP in the syllabus. The findings confirm the pivotal role teachers play in motivating L2 learners independent of the context they teach in; and, at the same time, call for further research so that we can better conceptualise the motivating influence of L2 teachers.Keywords: adult learners, corporate contexts, motivation, teacher’s role
Procedia PDF Downloads 10523811 Seismic Hazard Assessment of Offshore Platforms
Authors: F. D. Konstandakopoulou, G. A. Papagiannopoulos, N. G. Pnevmatikos, G. D. Hatzigeorgiou
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This paper examines the effects of pile-soil-structure interaction on the dynamic response of offshore platforms under the action of near-fault earthquakes. Two offshore platforms models are investigated, one with completely fixed supports and one with piles which are clamped into deformable layered soil. The soil deformability for the second model is simulated using non-linear springs. These platform models are subjected to near-fault seismic ground motions. The role of fault mechanism on platforms’ response is additionally investigated, while the study also examines the effects of different angles of incidence of seismic records on the maximum response of each platform.Keywords: hazard analysis, offshore platforms, earthquakes, safety
Procedia PDF Downloads 14823810 How Markets React to Corporate Disclosure: An Analysis Using a SEM Model
Authors: Helena Susana Afonso Alves, Natália Maria Rafael Canadas, Ana Maria Rodrigues
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We examined the impact of governance rules on information asymmetry, using the turnover ratio and the bid-ask spread as proxies for the information asymmetry. We used a SEM model and analyzed the indirect relations through the voluntary disclosure of information and the organizational performance. We built a voluntary disclosure index based on the information firms provided in their annual reports and divided the governance characteristics in two constructs: directors’ and supervisors’ structures and ownership structure. We concluded that the ownership structure exerts a direct influence on share price and share liquidity, Otherwise, the directors’ and supervisors’ structures exert an indirect influence, through the organizational performance and the voluntary disclosure of information. The results also show that for firms with high levels of disclosure the bid-ask spread is lower. However, in firms with a high ownership concentration investors tend to increase the bid-ask spreads and trade less, which, in this case, reduces the liquidity of the stock. The failure to find the relationship between voluntary disclosure of information and the turnover ratio shows us that the liquidity of shares is more related to the greater or lesser concentration of shareholders, with the performance of their companies than with the access to information. Moreover, it is clear that the role that information disclosure plays is mainly at the level of price formation.Keywords: corporate governance, information asymmetry, voluntary disclosure, structural equation modelling, SEM
Procedia PDF Downloads 51623809 Soil-Structure Interaction Models for the Reinforced Foundation System – A State-of-the-Art Review
Authors: Ashwini V. Chavan, Sukhanand S. Bhosale
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Challenges of weak soil subgrade are often resolved either by stabilization or reinforcing it. However, it is also practiced to reinforce the granular fill to improve the load-settlement behavior of over weak soil strata. The inclusion of reinforcement in the engineered granular fill provided a new impetus for the development of enhanced Soil-Structure Interaction (SSI) models, also known as mechanical foundation models or lumped parameter models. Several researchers have been working in this direction to understand the mechanism of granular fill-reinforcement interaction and the response of weak soil under the application of load. These models have been developed by extending available SSI models such as the Winkler Model, Pasternak Model, Hetenyi Model, Kerr Model etc., and are helpful to visualize the load-settlement behavior of a physical system through 1-D and 2-D analysis considering beam and plate resting on the foundation respectively. Based on the literature survey, these models are categorized as ‘Reinforced Pasternak Model,’ ‘Double Beam Model,’ ‘Reinforced Timoshenko Beam Model,’ and ‘Reinforced Kerr Model.’ The present work reviews the past 30+ years of research in the field of SSI models for reinforced foundation systems, presenting the conceptual development of these models systematically and discussing their limitations. Special efforts are taken to tabulate the parameters and their significance in the load-settlement analysis, which may be helpful in future studies for the comparison and enhancement of results and findings of physical models.Keywords: geosynthetics, mathematical modeling, reinforced foundation, soil-structure interaction, ground improvement, soft soil
Procedia PDF Downloads 12323808 Cerebrovascular Modeling: A Vessel Network Approach for Fluid Distribution
Authors: Karla E. Sanchez-Cazares, Kim H. Parker, Jennifer H. Tweedy
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The purpose of this work is to develop a simple compartmental model of cerebral fluid balance including blood and cerebrospinal-fluid (CSF). At the first level the cerebral arteries and veins are modelled as bifurcating trees with constant scaling factors between generations which are connected through a homogeneous microcirculation. The arteries and veins are assumed to be non-rigid and the cross-sectional area, resistance and mean pressure in each generation are determined as a function of blood volume flow rate. From the mean pressure and further assumptions about the variation of wall permeability, the transmural fluid flux can be calculated. The results suggest the next level of modelling where the cerebral vasculature is divided into three compartments; the large arteries, the small arteries, the capillaries and the veins with effective compliances and permeabilities derived from the detailed vascular model. These vascular compartments are then linked to other compartments describing the different CSF spaces, the cerebral ventricles and the subarachnoid space. This compartmental model is used to calculate the distribution of fluid in the cranium. Known volumes and flows for normal conditions are used to determine reasonable parameters for the model, which can then be used to help understand pathological behaviour and suggest clinical interventions.Keywords: cerebrovascular, compartmental model, CSF model, vascular network
Procedia PDF Downloads 27523807 Learning Model Applied to Cope with Professional Knowledge Gaps in Final Project of Information System Students
Authors: Ilana Lavy, Rami Rashkovits
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In this study, we describe Information Systems students' learning model which was applied by students in order to cope with professional knowledge gaps in the context of their final project. The students needed to implement a software system according to specifications and design they have made beforehand. They had to select certain technologies and use them. Most of them decided to use programming environments that were learned during their academic studies. The students had to cope with various levels of knowledge gaps. For that matter they used learning strategies that were organized by us as a learning model which includes two phases each suitable for different learning tasks. We analyze the learning model, describing advantages and shortcomings as perceived by the students, and provide excerpts to support our findings.Keywords: knowledge gaps, independent learner skills, self-regulated learning, final project
Procedia PDF Downloads 47823806 Influence of Microstructure on Deformation Mechanisms and Mechanical Properties of Additively Manufactured Steel
Authors: Etienne Bonnaud, David Lindell
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Correlations between microstructure, deformation mechanisms, and mechanical properties in additively manufactured 316L steel components have been investigated. Mechanical properties in the vertical direction (building direction) and in the horizontal direction (in plane directions) are markedly different. Vertically built specimens show lower yield stress but higher elongation than their horizontally built counterparts. Microscopic observations by electron back scattered diffraction (EBSD) for both build orientations reveal a strong [110] fiber texture in the build direction but different grain morphologies. These microstructures are used as input in subsequent crystal plasticity numerical simulations to understand their influence on the deformation mechanisms and the mechanical properties. Mean field simulations using a visco plastic self consistent (VPSC) model were carried out first but did not give results consistent with the tensile test experiments. A more detailed full-field model had to be used based on the Visco Plastic Fast Fourier Transform (VPFTT) method. A more accurate microstructure description was then input to the simulation model, where thin vertical regions of smaller grains were also taken into account. It turned out that these small grain clusters were responsible for the discrepancies in yield stress and hardening. Texture and morphology have a strong effect on mechanical properties. The different mechanical behaviors between vertically and horizontally printed specimens could be explained by means of numerical full-field crystal plasticity simulations, and the presence of thin clusters of smaller grains was shown to play a central role in the deformation mechanisms.Keywords: additive manufacturing, crystal plasticity, full-field simulations, mean-field simulations, texture
Procedia PDF Downloads 7023805 Patient Perspectives on the Role of Orthopedic Nurse Practitioners: A Cross-Sectional Study
Authors: Merav Ben Natan, May Revach, Or Sade, Yaniv Yonay, Yaron Berkovich
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Background: The inclusion of nurse practitioners (NPs) specializing in orthopedics holds promise for enhancing the quality of care for orthopedic patients. Understanding patients’ perspectives on this role is crucial for evaluating the feasibility and acceptance of integrating NPs into orthopedic settings. This study aims to explore the receptiveness of orthopedic patients to treatment by orthopedic NPs and examines potential associations between patients’ willingness to engage with NPs, their familiarity with the NP role, perceptions of nursing, and satisfaction with orthopedic nursing care. Methods: This cross-sectional study involved patients admitted to an orthopedic department at a central Israeli hospital between January and February 2023. Data was collected using a validated questionnaire consisting of five sections, reviewed by content experts. Statistical analyses were conducted using SPSS and included descriptive statistics, independent samples t-tests, Pearson correlations, and linear regression. Results: Participants in the study showed a moderate willingness to receive treatment from orthopedic NPs, with more than two-thirds expressing strong openness. Patients were generally receptive to NPs performing various clinical tasks, though there was less enthusiasm for NPs’ involvement in medication management and preoperative evaluations. Positive attitudes towards nurses and familiarity with the NP role were significant predictors of patient receptiveness to NP treatment. Conclusion: Patient acceptance of orthopedic NPs varies across different aspects of care. While there is a general willingness to receive care from NPs, these nuanced preferences must be considered when implementing NPs in orthopedic settings. Awareness and positive perceptions of the NP role play crucial roles in shaping patients’ willingness to engage with NPs.Keywords: orthopedic nurse practitioners, patient receptiveness, perceptions of nursing, clinical tasks
Procedia PDF Downloads 2823804 On-Line Data-Driven Multivariate Statistical Prediction Approach to Production Monitoring
Authors: Hyun-Woo Cho
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Detection of incipient abnormal events in production processes is important to improve safety and reliability of manufacturing operations and reduce losses caused by failures. The construction of calibration models for predicting faulty conditions is quite essential in making decisions on when to perform preventive maintenance. This paper presents a multivariate calibration monitoring approach based on the statistical analysis of process measurement data. The calibration model is used to predict faulty conditions from historical reference data. This approach utilizes variable selection techniques, and the predictive performance of several prediction methods are evaluated using real data. The results shows that the calibration model based on supervised probabilistic model yielded best performance in this work. By adopting a proper variable selection scheme in calibration models, the prediction performance can be improved by excluding non-informative variables from their model building steps.Keywords: calibration model, monitoring, quality improvement, feature selection
Procedia PDF Downloads 35623803 An in silico Approach for Exploring the Intercellular Communication in Cancer Cells
Authors: M. Cardenas-Garcia, P. P. Gonzalez-Perez
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Intercellular communication is a necessary condition for cellular functions and it allows a group of cells to survive as a population. Throughout this interaction, the cells work in a coordinated and collaborative way which facilitates their survival. In the case of cancerous cells, these take advantage of intercellular communication to preserve their malignancy, since through these physical unions they can send signs of malignancy. The Wnt/β-catenin signaling pathway plays an important role in the formation of intercellular communications, being also involved in a large number of cellular processes such as proliferation, differentiation, adhesion, cell survival, and cell death. The modeling and simulation of cellular signaling systems have found valuable support in a wide range of modeling approaches, which cover a wide spectrum ranging from mathematical models; e.g., ordinary differential equations, statistical methods, and numerical methods– to computational models; e.g., process algebra for modeling behavior and variation in molecular systems. Based on these models, different simulation tools have been developed from mathematical ones to computational ones. Regarding cellular and molecular processes in cancer, its study has also found a valuable support in different simulation tools that, covering a spectrum as mentioned above, have allowed the in silico experimentation of this phenomenon at the cellular and molecular level. In this work, we simulate and explore the complex interaction patterns of intercellular communication in cancer cells using the Cellulat bioinformatics tool, a computational simulation tool developed by us and motivated by two key elements: 1) a biochemically inspired model of self-organizing coordination in tuple spaces, and 2) the Gillespie’s algorithm, a stochastic simulation algorithm typically used to mimic systems of chemical/biochemical reactions in an efficient and accurate way. The main idea behind the Cellulat simulation tool is to provide an in silico experimentation environment that complements and guides in vitro experimentation in intra and intercellular signaling networks. Unlike most of the cell signaling simulation tools, such as E-Cell, BetaWB and Cell Illustrator which provides abstractions to model only intracellular behavior, Cellulat is appropriate for modeling both intracellular signaling and intercellular communication, providing the abstractions required to model –and as a result, simulate– the interaction mechanisms that involve two or more cells, that is essential in the scenario discussed in this work. During the development of this work we made evident the application of our computational simulation tool (Cellulat) for the modeling and simulation of intercellular communication between normal and cancerous cells, and in this way, propose key molecules that may prevent the arrival of malignant signals to the cells that surround the tumor cells. In this manner, we could identify the significant role that has the Wnt/β-catenin signaling pathway in cellular communication, and therefore, in the dissemination of cancer cells. We verified, using in silico experiments, how the inhibition of this signaling pathway prevents that the cells that surround a cancerous cell are transformed.Keywords: cancer cells, in silico approach, intercellular communication, key molecules, modeling and simulation
Procedia PDF Downloads 24923802 The Association between Attachment Styles, Satisfaction of Life, Alexithymia, and Psychological Resilience: The Mediational Role of Self-Esteem
Authors: Zahide Tepeli Temiz, Itir Tari Comert
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Attachment patterns based on early emotional interactions between infant and primary caregiver continue to be influential in adult life, in terms of mental health and behaviors of individuals. Several studies reveal that infant-caregiver relationships have impressed the affect regulation, coping with stressful and negative situations, general satisfaction of life, and self image in adulthood, besides the attachment styles. The present study aims to examine the relationships between university students’ attachment style and their self-esteem, alexithymic features, satisfaction of life, and level of resilience. In line with this aim, the hypothesis of the prediction of attachment styles (anxious and avoidant) over life satisfaction, self-esteem, alexithymia, and psychological resilience was tested. Additionally, in this study Structural Equational Modeling was conducted to investigate the mediational role of self-esteem in the relationship between attachment styles and alexithymia, life satisfaction, and resilience. This model was examined with path analysis. The sample of the research consists of 425 university students who take education from several region of Turkey. The participants who sign the informed consent completed the Demographic Information Form, Experiences in Close Relationships-Revised, Rosenberg Self-Esteem Scale, The Satisfaction with Life Scale, Toronto Alexithymia Scale, and Resilience Scale for Adults. According to results, anxious, and avoidant dimensions of insecure attachment predicted the self-esteem score and alexithymia in positive direction. On the other hand, these dimensions of attachment predicted life satisfaction in negative direction. The results of linear regression analysis indicated that anxious and avoidant attachment styles didn’t predict the resilience. This result doesn’t support the theory and research indicating the relationship between attachment style and psychological resilience. The results of path analysis revealed the mediational role self esteem in the relation between anxious, and avoidant attachment styles and life satisfaction. In addition, SEM analysis indicated the indirect effect of attachment styles over alexithymia and resilience besides their direct effect. These findings support the hypothesis of this research relation to mediating role of self-esteem. Attachment theorists suggest that early attachment experiences, including supportive and responsive family interactions, have an effect on resilience to harmful situations in adult life, ability to identify, describe, and regulate emotions and also general satisfaction with life. Several studies examining the relationship between attachment styles and life satisfaction, alexithymia, and psychological resilience draw attention to mediational role of self-esteem. Results of this study support the theory of attachment patterns with the mediation of self-image influence the emotional, cognitive, and behavioral regulation of person throughout the adulthood. Therefore, it is thought that any intervention intended for recovery in attachment relationship will increase the self-esteem, life satisfaction, and resilience level, on the one side, decrease the alexithymic features, on the other side.Keywords: alexithymia, anxious attachment, avoidant attachment, life satisfaction, path analysis, resilience, self-esteem, structural equation
Procedia PDF Downloads 19523801 Numerical Simulation of Fracturing Behaviour of Pre-Cracked Crystalline Rock Using a Cohesive Grain-Based Distinct Element Model
Authors: Mahdi Saadat, Abbas Taheri
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Understanding the cracking response of crystalline rocks at mineralogical scale is of great importance during the design procedure of mining structures. A grain-based distinct element model (GBM) is employed to numerically study the cracking response of Barre granite at micro- and macro-scales. The GBM framework is augmented with a proposed distinct element-based cohesive model to reproduce the micro-cracking response of the inter- and intra-grain contacts. The cohesive GBM framework is implemented in PFC2D distinct element codes. The microstructural properties of Barre granite are imported in PFC2D to generate synthetic specimens. The microproperties of the model is calibrated against the laboratory uniaxial compressive and Brazilian split tensile tests. The calibrated model is then used to simulate the fracturing behaviour of pre-cracked Barre granite with different flaw configurations. The numerical results of the proposed model demonstrate a good agreement with the experimental counterparts. The GBM framework proposed thus appears promising for further investigation of the influence of grain microstructure and mineralogical properties on the cracking behaviour of crystalline rocks.Keywords: discrete element modelling, cohesive grain-based model, crystalline rock, fracturing behavior
Procedia PDF Downloads 12923800 Role of Moderate Intensity Exercises in the Amelioration of Oxidant-Antioxidant Status and the Levels of Inflammatory Cytokines in Rheumatoid Arthritis Patients
Authors: Somaiya Mateen, Shagufta Moin, Abdul Qayyum, Atif Zafar
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Cytokines and reactive species play an important role in the pathophysiology of rheumatoid arthritis (RA). This study was done to determine the levels of reactive oxygen and nitrogen species (ROS and RNS), inflammatory cytokines and the markers of protein, DNA and lipid oxidation in the blood of RA patients, with the aim to study the antioxidant and anti-inflammatory role of moderate intensity exercises in the management of RA. RA patients were subdivided into two groups- first group (n=30) received treatment with conventional RA drugs while the second group (n=30) received moderate exercise therapy along with the conventional drugs for a period of 12 weeks. The levels of ROS, RNS, inflammatory cytokines and markers of biomolecule oxidation were monitored before and after 12 weeks of treatment. RA patients showed a marked increase in the levels of ROS, RNS, inflammatory cytokines, lipid, protein and DNA oxidation as compared to the healthy controls. These parameters were ameliorated after treatment with drugs alone and exercise combined with drugs, with the amelioration being more significant in patients given drugs along with the moderate intensity exercise treatment. In conclusion, the role of ROS, RNS and inflammatory cytokines in the pathogenesis of RA has been confirmed by this study. These may also serve as potential biomarker for assessing the disease severity. Finally, the addition of moderate intensity exercises in the management of RA may be of great value.Keywords: rheumatoid arthritis, reactive oxygen species, inflammatory cytokines, moderate intensity exercises
Procedia PDF Downloads 33323799 In vivo Wound Healing Activity and Phytochemical Screening of the Crude Extract and Various Fractions of Kalanchoe petitiana A. Rich (Crassulaceae) Leaves in Mice
Authors: Awol Mekonnen, Temesgen Sidamo, Epherm Engdawork, Kaleab Asresb
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Ethnopharmacological Relevance: The leaves of Kalanchoe petitiana A. Rich (Crassulaceae) are used in Ethiopian folk medicine for treatment of evil eye, fractured surface for bone setting and several skin disorders including for the treatment of sores, boils, and malignant wounds. Aim of the Study: In order to scientifically prove the claimed utilization of the plant, the effects of the extracts and the fractions were investigated using in vivo excision, incision and dead space wound models. Materials and Method: Mice were used for wound healing study, while rats and rabbit were used for skin irritation test. For studying healing activity, 80% methanolic extract and the fractions were formulated in strength of 5% and 10%, either as ointment (hydroalcoholic extract, aqueous and methanol fractions) or gel (chloroform fraction). Oral administration of the crude extract was used for dead space model. Negative controls were treated either with simple ointment or sodium carboxyl methyl cellulose xerogel, while positive controls were treated with nitrofurazone (0.2 w/v) skin ointment. Negative controls for dead space model were treated with 1% carboxy methyl cellulose. Parameters, including rate of wound contraction, period of complete epithelializtion, hydroxyproline contents and skin breaking strength were evaluated. Results: Significant wound healing activity was observed with ointment formulated from the crude extract at both 5% and 10% concentration (p<0.01) compared to controls in both excision and incision models. In dead space model, 600 mg/kg (p<0.01), but not 300 mg/kg, significantly increased hydroxyproline content. Fractions showed variable effect, with the chloroform fraction lacking any significant effect. Both 5% and 10% formulations of the aqueous and methanolic fractions significantly increased wound contraction, decreased epithelializtion time and increased hydroxyproline content in excision wound model (p<0.05) as compared to controls. These fractions were also endowed with higher skin breaking strength in incision wound model (p<0.01). Conclusions: The present study provided evidence that the leaves of Kalanchoe petitiana A. Rich possess remarkable wound healing activities supporting the folkloric assertion of the plant. Fractionation revealed that polar or semi-polar compound may play vital role, as both aqueous and methanolic fractions were endowed with wound healing activity.Keywords: wound healing, Kalanchoae petitiana, excision wound, incision wound, dead space model
Procedia PDF Downloads 30923798 The Role of the State Budget: An Evaluation of Public Expenditures and Taxes in Turkey
Authors: Erdal Eroğlu, Özhan Çetinkaya
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The purpose of this paper is to show how state plays a regulatory role in the relations of distribution by analyzing tax and expenditure in Turkey. This paper has two main arguments. First, state intervenes in economic and social life via budget policies and steers the relations of distribution within the scope of the reproduction of the capital accumulation and legitimacy. Secondly, a great amount of public expenditure benefits capital owners while state gains its tax income mainly from low and middle income groups.Keywords: distribution, public expenditure, state budget, taxes
Procedia PDF Downloads 531