Search results for: transformational collegial leadership model
15942 Bifurcation and Chaos of the Memristor Circuit
Authors: Wang Zhulin, Min Fuhong, Peng Guangya, Wang Yaoda, Cao Yi
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In this paper, a magnetron memristor model based on hyperbolic sine function is presented and the correctness proved by studying the trajectory of its voltage and current phase, and then a memristor chaotic system with the memristor model is presented. The phase trajectories and the bifurcation diagrams and Lyapunov exponent spectrum of the magnetron memristor system are plotted by numerical simulation, and the chaotic evolution with changing the parameters of the system is also given. The paper includes numerical simulations and mathematical model, which confirming that the system, has a wealth of dynamic behavior.Keywords: memristor, chaotic circuit, dynamical behavior, chaotic system
Procedia PDF Downloads 50415941 A Machine Learning Model for Predicting Students’ Academic Performance in Higher Institutions
Authors: Emmanuel Osaze Oshoiribhor, Adetokunbo MacGregor John-Otumu
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There has been a need in recent years to predict student academic achievement prior to graduation. This is to assist them in improving their grades, especially for those who have struggled in the past. The purpose of this research is to use supervised learning techniques to create a model that predicts student academic progress. Many scholars have developed models that predict student academic achievement based on characteristics including smoking, demography, culture, social media, parent educational background, parent finances, and family background, to mention a few. This element, as well as the model used, could have misclassified the kids in terms of their academic achievement. As a prerequisite to predicting if the student will perform well in the future on related courses, this model is built using a logistic regression classifier with basic features such as the previous semester's course score, attendance to class, class participation, and the total number of course materials or resources the student is able to cover per semester. With a 96.7 percent accuracy, the model outperformed other classifiers such as Naive bayes, Support vector machine (SVM), Decision Tree, Random forest, and Adaboost. This model is offered as a desktop application with user-friendly interfaces for forecasting student academic progress for both teachers and students. As a result, both students and professors are encouraged to use this technique to predict outcomes better.Keywords: artificial intelligence, ML, logistic regression, performance, prediction
Procedia PDF Downloads 10915940 Multistage Data Envelopment Analysis Model for Malmquist Productivity Index Using Grey's System Theory to Evaluate Performance of Electric Power Supply Chain in Iran
Authors: Mesbaholdin Salami, Farzad Movahedi Sobhani, Mohammad Sadegh Ghazizadeh
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Evaluation of organizational performance is among the most important measures that help organizations and entities continuously improve their efficiency. Organizations can use the existing data and results from the comparison of units under investigation to obtain an estimation of their performance. The Malmquist Productivity Index (MPI) is an important index in the evaluation of overall productivity, which considers technological developments and technical efficiency at the same time. This article proposed a model based on the multistage MPI, considering limited data (Grey’s theory). This model can evaluate the performance of units using limited and uncertain data in a multistage process. It was applied by the electricity market manager to Iran’s electric power supply chain (EPSC), which contains uncertain data, to evaluate the performance of its actors. Results from solving the model showed an improvement in the accuracy of future performance of the units under investigation, using the Grey’s system theory. This model can be used in all case studies, in which MPI is used and there are limited or uncertain data.Keywords: Malmquist Index, Grey's Theory, CCR Model, network data envelopment analysis, Iran electricity power chain
Procedia PDF Downloads 16515939 Geometric Contrast of a 3D Model Obtained by Means of Digital Photogrametry with a Quasimetric Camera on UAV Classical Methods
Authors: Julio Manuel de Luis Ruiz, Javier Sedano Cibrián, Rubén Pérez Álvarez, Raúl Pereda García, Cristina Diego Soroa
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Nowadays, the use of drones has been extended to practically any human activity. One of the main applications is focused on the surveying field. In this regard, software programs that process the images captured by the sensor from the drone in an almost automatic way have been developed and commercialized, but they only allow contrasting the results through control points. This work proposes the contrast of a 3D model obtained from a flight developed by a drone and a non-metric camera (due to its low cost), with a second model that is obtained by means of the historically-endorsed classical methods. In addition to this, the contrast is developed over a certain territory with a significant unevenness, so as to test the model generated with photogrammetry, and considering that photogrammetry with drones finds more difficulties in terms of accuracy in this kind of situations. Distances, heights, surfaces and volumes are measured on the basis of the 3D models generated, and the results are contrasted. The differences are about 0.2% for the measurement of distances and heights, 0.3% for surfaces and 0.6% when measuring volumes. Although they are not important, they do not meet the order of magnitude that is presented by salespeople.Keywords: accuracy, classical topographic, model tridimensional, photogrammetry, Uav.
Procedia PDF Downloads 13615938 Gender Equality and the Politics of Presence among the Maasai in Kenya
Authors: Shillah Memusi
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Underrepresentation of women in governance structures is a global phenomenon, with patriarchal considerations being among the main, if not the top, reason for this in Sub Saharan Africa. This paper demonstrates that gender norms and informal rules have perpetuated a culture of stereotypical gender roles that have limited women’s public participation and leadership in society. To achieve this, the paper explores barriers to women’s political engagement, and how these are navigated in the face of gender equality laws. Situated in Kenya’s Maasai community, the paper investigates the influence of set laws on the increased involvement of women from the patriarchal community in the political economy. It gives special attention to the intersectionality of formal and informal laws and the subsequent interpretation and implementation of gender equality. The paper then concludes by demonstrating the benefits of exploring alternative gender equality pathways, as informed by contextual realities of settings such as patriarchal communities.Keywords: equality, Kenya, patriarchy, public participation, women
Procedia PDF Downloads 30015937 Building Information Management in Context of Urban Spaces, Analysis of Current Use and Possibilities
Authors: Lucie Jirotková, Daniel Macek, Andrea Palazzo, Veronika Malinová
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Currently, the implementation of 3D models in the construction industry is gaining popularity. Countries around the world are developing their own modelling standards and implement the use of 3D models into their individual permitting processes. Another theme that needs to be addressed are public building spaces and their subsequent maintenance, where the usage of BIM methodology is directly offered. The significant benefit of the implementation of Building Information Management is the information transfer. The 3D model contains not only the spatial representation of the item shapes but also various parameters that are assigned to the individual elements, which are easily traceable, mainly because they are all stored in one place in the BIM model. However, it is important to keep the data in the models up to date to achieve useability of the model throughout the life cycle of the building. It is now becoming standard practice to use BIM models in the construction of buildings, however, the building environment is very often neglected. Especially in large-scale development projects, the public space of buildings is often forwarded to municipalities, which obtains the ownership and are in charge of its maintenance. A 3D model of the building surroundings would include both the above-ground visible elements of the development as well as the underground parts, such as the technological facilities of water features, electricity lines for public lighting, etc. The paper shows the possibilities of a model in the field of information for the handover of premises, the following maintenance and decision making. The attributes and spatial representation of the individual elements make the model a reliable foundation for the creation of "Smart Cities". The paper analyses the current use of the BIM methodology and presents the state-of-the-art possibilities of development.Keywords: BIM model, urban space, BIM methodology, facility management
Procedia PDF Downloads 12415936 A Frictional-Collisional Closure Model for the Saturated Granular Flow: Experimental Evidence and Two Phase Modelling
Authors: Yunhui Sun, Qingquan Liu, Xiaoliang Wang
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Dense granular flows widely exist in geological flows such as debris flow, landslide, or sheet flow, where both the interparticle and solid-liquid interactions are important to modify the flow. So, a two-phase approach with both phases correctly modelled is important for a better investigation of the saturated granular flows. However, a proper closure model covering a wide range of flowing states for the solid phase is still lacking. This study first employs a chute flow experiment based on the refractive index matching method, which makes it possible to obtain internal flow information such as velocity, shear rate, granular fluctuation, and volume fraction. The granular stress is obtained based on a steady assumption. The kinetic theory is found to describe the stress dependence on the flow state well. More importantly, the granular rheology is found to be frictionally dominated under weak shear and collisionally dominated under strong shear. The results presented thus provide direct experimental evidence on a possible frictional-collisional closure model for the granular phase. The data indicates that both frictional stresses exist over a wide range of the volume fraction, though traditional theory believes it vanishes below a critical volume fraction. Based on the findings, a two-phase model is used to simulate the chute flow. Both phases are modelled as continuum media, and the inter-phase interactions, such as drag force and pressure gradient force, are considered. The frictional-collisional model is used for the closure of the solid phase stress. The profiles of the kinematic properties agree well with the experiments. This model is further used to simulate immersed granular collapse, which is unsteady in nature, to study the applicability of this model, which is derived from steady flow.Keywords: closure model, collision, friction, granular flow, two-phase model
Procedia PDF Downloads 5915935 Characteristics of Pakistani Business Leaders: A Psychological Perspective
Authors: Hafiz Haseeb Nisar, Maryam Bilal
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This qualitative study was conducted to investigate the underlying dynamics, key success factors and characteristics of Pakistani business leaders. The sample included 5 top businessmen from different business sectors. They were approached through the magazine “Manager Today” office in Lahore. Semi-structured interview technique was used to understand their experiences, attitudes, styles of management and key factors in their business success. Grounded theory was employed to analyze data. The following themes emerged as characteristics of business leaders: optimism, assertiveness, professionalism, effective management style, business knowledge/ excellence, supportive family and strong faith in God. It was noted that all these were interlinked, which leads the businessmen to become a successful business tycoon of this country. The importance of this study rests in its eastern contribution to the theoretical framework of the psychology of business leaders and particularly these findings will help to realize the basic key factors of success behind a business leader in Pakistan.Keywords: business psychology, characteristics, key personality factors, leadership
Procedia PDF Downloads 14915934 Time Series Modelling and Prediction of River Runoff: Case Study of Karkheh River, Iran
Authors: Karim Hamidi Machekposhti, Hossein Sedghi, Abdolrasoul Telvari, Hossein Babazadeh
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Rainfall and runoff phenomenon is a chaotic and complex outcome of nature which requires sophisticated modelling and simulation methods for explanation and use. Time Series modelling allows runoff data analysis and can be used as forecasting tool. In the paper attempt is made to model river runoff data and predict the future behavioural pattern of river based on annual past observations of annual river runoff. The river runoff analysis and predict are done using ARIMA model. For evaluating the efficiency of prediction to hydrological events such as rainfall, runoff and etc., we use the statistical formulae applicable. The good agreement between predicted and observation river runoff coefficient of determination (R2) display that the ARIMA (4,1,1) is the suitable model for predicting Karkheh River runoff at Iran.Keywords: time series modelling, ARIMA model, river runoff, Karkheh River, CLS method
Procedia PDF Downloads 34115933 Men’s Engagement in Intimate Partner Violence (IPV) Prevention Programs
Authors: Zeynep Turhan
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This review emphasized the effectiveness of men’s participation, and whether non-violent (NV) boys’ and men’s perceptions of IPV prevention programs affect their involvement. Additionally, the review aimed to identify the barriers of non-engagement as well as the most effective approaches to end and prevent violence-against-women (VAW). The main goals of this assessment were to investigate 1) how NV men engage in anti-violence prevention programs that empower women, 2) what are the possible perceptions of NV men involved in prevention programs 3) how to identify effective approaches and strategies that encourage NV men to become involved in prevention programs. This critical review also included the overview of prevention programs such as The Mentors in Violence Prevention Programs (MVP), The White Ribbon Campaign (WRC), and Domestic Violence Prevention Enhancement and Leadership through Alliances (DELTA). The review recommended expanding these programs to reach more macro settings such as workplace, faith-based and other community-based organizations. Additionally, secondary and territory prevention programs need to expand through addressing the long-term effects of violence.Keywords: engagement, non-violent men, prevention programs
Procedia PDF Downloads 41715932 A Graph SEIR Cellular Automata Based Model to Study the Spreading of a Transmittable Disease
Authors: Natasha Sharma, Kulbhushan Agnihotri
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Cellular Automata are discrete dynamical systems which are based on local character and spatial disparateness of the spreading process. These factors are generally neglected by traditional models based on differential equations for epidemic spread. The aim of this work is to introduce an SEIR model based on cellular automata on graphs to imitate epidemic spreading. Distinctively, it is an SEIR-type model where the population is divided into susceptible, exposed, infected and recovered individuals. The results obtained from simulations are in accordance with the spreading behavior of a real time epidemics.Keywords: cellular automata, epidemic spread, graph, susceptible
Procedia PDF Downloads 45915931 Evaluation of Long Term Evolution Mobile Signal Propagation Models and Vegetation Attenuation in the Livestock Department at Escuela Superior Politécnica de Chimborazo
Authors: Cinthia Campoverde, Mateo Benavidez, Victor Arias, Milton Torres
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This article evaluates and compares three propagation models: the Okumura-Hata model, the Ericsson 9999 model, and the SUI model. The inclusion of vegetation attenuation in the area is also taken into account. These mathematical models aim to predict the power loss between a transmitting antenna (Tx) and a receiving antenna (Rx). The study was conducted in the open areas of the Livestock Department at the Escuela Superior Politécnica de Chimborazo (ESPOCH) University, located in the city of Riobamba, Ecuador. The necessary parameters for each model were calculated, considering LTE technology. The transmitting antenna belongs to the mobile phone company ”TUENTI” in Band 2, operating at a frequency of 1940 MHz. The reception power data in the area were empirically measured using the ”Network Cell Info” application. A total of 170 samples were collected, distributed across 19 radius, forming concentric circles around the transmitting antenna. The results demonstrate that the Okumura Hata urban model provides the best fit to the measured data.Keywords: propagation models, reception power, LTE, power losses, correction factor
Procedia PDF Downloads 8215930 Investigating the Dynamics of Knowledge Acquisition in Undergraduate Mathematics Students Using Differential Equations
Authors: Gilbert Makanda
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The problem of the teaching of mathematics is studied using differential equations. A mathematical model for knowledge acquisition in mathematics is developed. In this study we adopt the mathematical model that is normally used for disease modelling in the teaching of mathematics. It is assumed that teaching is 'infecting' students with knowledge thereby spreading this knowledge to the students. It is also assumed that students who gain this knowledge spread it to other students making disease model appropriate to adopt for this problem. The results of this study show that increasing recruitment rates, learning contact with teachers and learning materials improves the number of knowledgeable students. High dropout rates and forgetting taught concepts also negatively affect the number of knowledgeable students. The developed model is then solved using Matlab ODE45 and \verb"lsqnonlin" to estimate parameters for the actual data.Keywords: differential equations, knowledge acquisition, least squares, dynamical systems
Procedia PDF Downloads 42315929 E-Bike FE Model Analysis: Connection Stiffness of Elements with Different DOFs
Authors: Lele Zhang, Hui Leng Choo, Alexander Konyukhov, Shuguang Li
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Finite Element (FE) model of simplified e-bike structure was generated by main frame with two tiers, which consisted of pipe, mass, beam, and shell elements (pipe 289, beam188, shell 181, shell 281, combin14, link11, mass21). These elements would be introduced and demonstrated using mathematical formulas. Based on coupling theory, constrain equations was proposed. Exporting all the parameters obtained from theory part, the connection stiffness matrix of the whole e-bike structure between each of these elements was detected.Keywords: coupling theory, stiffness matrix, e-bike, finite element model
Procedia PDF Downloads 37515928 Developing a Model – an Application of Fuzzy Analytic Network Process Techniques for Hostels
Authors: Pin-Ju Juan, Peng-Yu Juan, Yi-Shan Chen
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The main purpose of this paper is to present a fuzzy Analytic Network Process (ANP) model for the hostel organizational performance selection. In this article, we created 39 criteria for selecting hostel organizational performance acquired from literature's review and experts method practical investigations, and the methods of fuzzy analytic network process are used to consolidate decision-makers’ assessments about criteria weightings. Finally, we selected organizational performance of a hostel in Taiwan to determine the effectiveness of the proposed evaluation model in this paper.Keywords: Fuzzy ANP, hostel, organizational performance, strategy management
Procedia PDF Downloads 20015927 Modeling of Masonry In-Filled R/C Frame to Evaluate Seismic Performance of Existing Building
Authors: Tarek M. Alguhane, Ayman H. Khalil, M. N. Fayed, Ayman M. Ismail
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This paper deals with different modeling aspects of masonry infill: no infill model, Layered shell infill model, and strut infill model. These models consider the complicated behavior of the in-filled plane frames under lateral load similar to an earthquake load. Three strut infill models are used: NBCC (2005) strut infill model, ASCE/SEI 41-06 strut infill model and proposed strut infill model based on modification to Canadian, NBCC (2005) strut infill model. Pushover and modal analyses of a masonry infill concrete frame with a single storey and an existing 5-storey RC building have been carried out by using different models for masonry infill. The corresponding hinge status, the value of base shear at target displacement as well as their dynamic characteristics have been determined and compared. A validation of the structural numerical models for the existing 5-storey RC building has been achieved by comparing the experimentally measured and the analytically estimated natural frequencies and their mode shapes. This study shows that ASCE/SEI 41-06 equation underestimates the values for the equivalent properties of the diagonal strut while Canadian, NBCC (2005) equation gives realistic values for the equivalent properties. The results indicate that both ASCE/SEI 41-06 and Canadian, NBCC (2005) equations for strut infill model give over estimated values for dynamic characteristic of the building. Proposed modification to Canadian, NBCC (2005) equation shows that the fundamental dynamic characteristic values of the building are nearly similar to the corresponding values using layered shell elements as well as measured field results.Keywords: masonry infill, framed structures, RC buildings, non-structural elements
Procedia PDF Downloads 27715926 The Implementation of Strengthening Institutional Model of Women Farmers Group in Developing Household Food Security
Authors: Rahmadanih, Sitti Bulkis, A. Amrullah, R. M. Rukka, N. M. Viantika
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Food security is still a global issue, including in Indonesia. In South Sulawesi, this issue also occurs in members of farmer groups/women farmer groups. This study aims to (1) describe the implementation of strengthening institutional model of Women Farmer Groups (WFG) and (2) analyzing the capacity building of WFG members in order to develop food security after the implementations on institutional model. The research was conducted in Bulukumba and Luwu Utara District, South Sulawesi, Indonesia. The research was designed with qualitative and quantitative (mixed) method. Qualitative data were collected through in-depth interview and Focus Group Discussion (FGD); while quantitative data collected through a household survey of WGF members. Two WGF were selected they are WFG in Bulukumba and WGF in Luwu Utara District. Both WGF has been selected as the case unit, which consisting of 60 households. Institutional strengthening model that been implemented is a combination model of (1) institutional support and (2) capacity development of WGF members. The model of institutional support aim is to develop food security could be achieved through facilitation on produce banana chips (initiate a business group formation) and preparation of institution rule (AD/ART). (2) The developing Model of WFG members capacity building are (a) technical training of banana chips producing process, also food and nutrition counseling as well as the utilization of the yard, (b) processing of food products from their yards. Food and nutrition knowledge of WFG members was increased about 30% - 60% and accompanied by the development of households’ food security by 6.7% - 10.0%.; when compared to last year percentage.Keywords: food security, institutional strengthening, model implementation, women farmer group
Procedia PDF Downloads 18115925 The Russian-Ukrainian Conflict: An Imperial, Neoliberal Limbo
Authors: Anna Savchenko
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The dissolution of the Soviet Union brought about a wave of decolonisation throughout the Soviet space in the 1990s. While this emancipation ushered in an era of reform in the newly independent states, it also opened up the opportunity for countries such as Ukraine to be (re)colonised by a different ruling power: the European Union. Ukraine’s relationship with the EU has been further complicated by the fact that the country’s political leadership has aligned itself with a Western agenda of democratisation. This article challenges the neoliberal belief that the global market can spurn democratisation by analysing the way in which market privatisation in Ukraine has allowed for mass corruption to flourish. I submit that neoliberalism, or the sheer force of the global market, is just as colonising as modern-day imperialism has proven to be by providing an analytical synthesis of Russia and Ukraine’s century-old conflict. The EU’s demonstrated inability to mediate cross-border conflict in the region foreshadows that Ukraine may have been economically colonised by another failing state.Keywords: neoliberalism, imperealism, Russian-Ukrainian conflict, democratisation, colonisation
Procedia PDF Downloads 18315924 Poverty Dynamics in Thailand: Evidence from Household Panel Data
Authors: Nattabhorn Leamcharaskul
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This study aims to examine determining factors of the dynamics of poverty in Thailand by using panel data of 3,567 households in 2007-2017. Four techniques of estimation are employed to analyze the situation of poverty across households and time periods: the multinomial logit model, the sequential logit model, the quantile regression model, and the difference in difference model. Households are categorized based on their experiences into 5 groups, namely chronically poor, falling into poverty, re-entering into poverty, exiting from poverty and never poor households. Estimation results emphasize the effects of demographic and socioeconomic factors as well as unexpected events on the economic status of a household. It is found that remittances have positive impact on household’s economic status in that they are likely to lower the probability of falling into poverty or trapping in poverty while they tend to increase the probability of exiting from poverty. In addition, not only receiving a secondary source of household income can raise the probability of being a never poor household, but it also significantly increases household income per capita of the chronically poor and falling into poverty households. Public work programs are recommended as an important tool to relieve household financial burden and uncertainty and thus consequently increase a chance for households to escape from poverty.Keywords: difference in difference, dynamic, multinomial logit model, panel data, poverty, quantile regression, remittance, sequential logit model, Thailand, transfer
Procedia PDF Downloads 11215923 Improving Pneumatic Artificial Muscle Performance Using Surrogate Model: Roles of Operating Pressure and Tube Diameter
Authors: Van-Thanh Ho, Jaiyoung Ryu
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In soft robotics, the optimization of fluid dynamics through pneumatic methods plays a pivotal role in enhancing operational efficiency and reducing energy loss. This is particularly crucial when replacing conventional techniques such as cable-driven electromechanical systems. The pneumatic model employed in this study represents a sophisticated framework designed to efficiently channel pressure from a high-pressure reservoir to various muscle locations on the robot's body. This intricate network involves a branching system of tubes. The study introduces a comprehensive pneumatic model, encompassing the components of a reservoir, tubes, and Pneumatically Actuated Muscles (PAM). The development of this model is rooted in the principles of shock tube theory. Notably, the study leverages experimental data to enhance the understanding of the interplay between the PAM structure and the surrounding fluid. This improved interactive approach involves the use of morphing motion, guided by a contraction function. The study's findings demonstrate a high degree of accuracy in predicting pressure distribution within the PAM. The model's predictive capabilities ensure that the error in comparison to experimental data remains below a threshold of 10%. Additionally, the research employs a machine learning model, specifically a surrogate model based on the Kriging method, to assess and quantify uncertainty factors related to the initial reservoir pressure and tube diameter. This comprehensive approach enhances our understanding of pneumatic soft robotics and its potential for improved operational efficiency.Keywords: pneumatic artificial muscles, pressure drop, morhing motion, branched network, surrogate model
Procedia PDF Downloads 9815922 Stoner Impurity Model in Nickel Hydride
Authors: Andrea Leon, J. M. Florez, P. Vargas
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The effect of hydrogen adsorption on the magnetic properties of fcc Ni has been calculated using the linear-muffin-tin-orbital formalism and using the local-density approximation for the exchange y correlation. The calculations for the ground state show that the sequential addition of hydrogen atoms is found to monotonically reduce the total magnetic moment of the Ni fcc structure, as a result of changes in the exchange-splitting parameter and in the Fermi energy. In order to physically explain the effect of magnetization reduction as the Hydrogen concentration increases, we propose a Stoner impurity model to describe the influence of H impurity on the magnetic properties of Nickel.Keywords: electronic structure, magnetic properties, Nickel hydride, stoner model
Procedia PDF Downloads 45915921 Dynamic Model of Automatic Loom on SimulationX
Authors: A. Jomartov, A. Tuleshov, B. Tultaev
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One of the main tasks in the development of textile machinery is to increase the rapidity of automatic looms, and consequently, their productivity. With increasing automatic loom speeds, the dynamic loads on their separate mechanisms and moving joints sharply increase. Dynamic research allows us to determine the weakest mechanisms of the automatic loom. The modern automatic loom consists of a large number of structurally different mechanisms. These are cam, lever, gear, friction and combined cyclic mechanisms. The modern automatic loom contains various mechatronic devices: A device for the automatic removal of faulty weft, electromechanical drive warp yarns, electronic controllers, servos, etc. In the paper, we consider the multibody dynamic model of the automatic loom on the software complex SimulationX. SimulationX is multidisciplinary software for modeling complex physical and technical facilities and systems. The multibody dynamic model of the automatic loom allows consideration of: The transition processes, backlash at the joints and nodes, the force of resistance and electric motor performance.Keywords: automatic loom, dynamics, model, multibody, SimulationX
Procedia PDF Downloads 34815920 Towards a Security Model against Denial of Service Attacks for SIP Traffic
Authors: Arellano Karina, Diego Avila-Pesántez, Leticia Vaca-Cárdenas, Alberto Arellano, Carmen Mantilla
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Nowadays, security threats in Voice over IP (VoIP) systems are an essential and latent concern for people in charge of security in a corporate network, because, every day, new Denial-of-Service (DoS) attacks are developed. These affect the business continuity of an organization, regarding confidentiality, availability, and integrity of services, causing frequent losses of both information and money. The purpose of this study is to establish the necessary measures to mitigate DoS threats, which affect the availability of VoIP systems, based on the Session Initiation Protocol (SIP). A Security Model called MS-DoS-SIP is proposed, which is based on two approaches. The first one analyzes the recommendations of international security standards. The second approach takes into account weaknesses and threats. The implementation of this model in a VoIP simulated system allowed to minimize the present vulnerabilities in 92% and increase the availability time of the VoIP service into an organization.Keywords: Denial-of-Service SIP attacks, MS-DoS-SIP, security model, VoIP-SIP vulnerabilities
Procedia PDF Downloads 20315919 An Exploration of the Emergency Staff’s Perceptions and Experiences of Teamwork and the Skills Required in the Emergency Department in Saudi Arabia
Authors: Sami Alanazi
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Teamwork practices have been recognized as a significant strategy to improve patient safety, quality of care, and staff and patient satisfaction in healthcare settings, particularly within the emergency department (ED). The EDs depend heavily on teams of interdisciplinary healthcare staff to carry out their operational goals and core business of providing care to the serious illness and injured. The ED is also recognized as a high-risk area in relation to service demand and the potential for human error. Few studies have considered the perceptions and experiences of the ED staff (physicians, nurses, allied health professionals, and administration staff) about the practice of teamwork, especially in Saudi Arabia (SA), and no studies have been conducted to explore the practices of teamwork in the EDs. Aim: To explore the practices of teamwork from the perspectives and experiences of staff (physicians, nurses, allied health professionals, and administration staff) when interacting with each other in the admission areas in the ED of a public hospital in the Northern Border region of SA. Method: A qualitative case study design was utilized, drawing on two methods for the data collection, comprising of semi-structured interviews (n=22) with physicians (6), nurses (10), allied health professionals (3), and administrative members (3) working in the ED of a hospital in the Northern Border region of SA. The second method is non-participant direct observation. All data were analyzed using thematic analysis. Findings: The main themes that emerged from the analysis were as follows: the meaningful of teamwork, reasons of teamwork, the ED environmental factors, the organizational factors, the value of communication, leadership, teamwork skills in the ED, team members' behaviors, multicultural teamwork, and patients and families behaviors theme. Discussion: Working in the ED environment played a major role in affecting work performance as well as team dynamics. However, Communication, time management, fast-paced performance, multitasking, motivation, leadership, and stress management were highlighted by the participants as fundamental skills that have a major impact on team members and patients in the ED. It was found that the behaviors of the team members impacted the team dynamics as well as ED health services. Behaviors such as disputes among team members, conflict, cooperation, uncooperative members, neglect, and emotions of the members. Besides that, the behaviors of the patients and their accompanies had a direct impact on the team and the quality of the services. In addition, the differences in the cultures have separated the team members and created undesirable gaps such the gender segregation, national origin discrimination, and similarity and different in interests. Conclusion: Effective teamwork, in the context of the emergency department, was recognized as an essential element to obtain the quality of care as well as improve staff satisfaction.Keywords: teamwork, barrier, facilitator, emergencydepartment
Procedia PDF Downloads 14015918 Application of Terminal Sliding Mode Control to the Stabilization of the Indoor Temperature in Buildings
Authors: Pawel Skruch, Marek Dlugosz
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The paper starts with a general model of the temperature dynamics in buildings. The modelling approach relies on thermodynamics, in particular heat transfer, principles. The model considers heat loses by conduction and ventilation and internal heat gains. The parameters of the model can be determined uniquely from the geometry of the building and from thermal properties of construction materials. The model is presented using state space notation and this form is used in the control design procedure. A sliding surface is defined by the system output and the desired trajectory. The control law is designed to force the trajectory of the system from any initial condition to the sliding surface in finite time. The trajectory of the system after reaching the sliding surface remains on it. A simulation example is included to verify the approach and to demonstrate the achievable performance improvement by the proposed solution in the temperature control in buildings.Keywords: modelling, building, temperature dynamics, sliding-mode control, sliding surface
Procedia PDF Downloads 54915917 The Limits of Charity: Advancing a Rights-based Justice Model to Remedy Poverty and Hunger
Authors: Tracy Smith-Carrier
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In 1995, the World Health Organization declared that poverty was the biggest killer and the greatest cause of suffering in the world. Income is certainly a key social determinant of health, the lack of which causes innumerable health and mental health conditions. In seeking to provide relief from financial hardship for residents within their populace, states in the Global North have largely turned to the non-profit and charitable sector. The stigma and shame of accessing charity is a significant barrier for many, but what is more problematic is that the embrace of the charitable model has let governments off the hook from responding to their international human rights obligations. Although states are signatories to various human rights treaties and conventions internationally, many of these laws have not been implemented domestically. This presentation explores the limits of the charitable model in addressing poverty in countries of the Global North. Unlike in the ages passed, when poverty was thought to be an individual problem, we now know that poverty is largely systemic in nature. In this presentation, we will identify the structural determinants of poverty, outline why people are reticent to access charitable programs and services and how income security is reproduced through the charitable model, and discuss evidence-informed solutions, such as a basic income guarantee, to move beyond the charitable model in favour of a rights-based justice model. To move beyond charity, we must demand that governments recognize our fundamental human rights and address poverty and hunger using a justice model based on substantive human rights.Keywords: basic income, charity, poverty, income security, hunger, food security, social justice, human rights
Procedia PDF Downloads 11715916 Numerical Analysis of the Effect of Height and Rate of Fluid Flow on a Stepped Spillway
Authors: Amir Abbas Kamanbedast, Abbas Saki
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Stepped spillways are composed of several steps, which start from around the spillway crest and continue to the downstream heel. Recently, such spillways have been receiving increasing attention due to the significant effect of the associated stairs on the flow’s rate of energy dissipation. Energy dissipation in the stepped spillways across the overflow can be explained by the watercourse contact with the stairs (i.e., large, harsh surfaces). In this context, less energy must be dissipated at the end of the spillway, and, hence, a smaller (less expensive) energy-dissipating structure is required. In this study, a stepped spillway was simulated using the model Fluent 3, and a standard model was used to model the flow disturbance. For this purpose, the energy dissipation from the stepped spillway was investigated in terms of the different numbers of stairs involved. Using k-ε, the disturbances of the numerical method for velocity and of flow depth at the downstream overflow were obtained, and, then, the energy that was dissipated throughout the spillway was calculated. Our results showed that an increase in the number of stairs can considerably increase the amount of energy dissipation for the fixed, upstream energy. In addition, the results of the numerical analyses were provided as isobar and velocity curves so points that were sensitive to cavitation could be determined.Keywords: stepped spillway, fluent software, turbulence model of k-ε, VOF model
Procedia PDF Downloads 29915915 Simulation of Dynamic Behavior of Seismic Isolators Using a Parallel Elasto-Plastic Model
Authors: Nicolò Vaiana, Giorgio Serino
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In this paper, a one-dimensional (1d) Parallel Elasto- Plastic Model (PEPM), able to simulate the uniaxial dynamic behavior of seismic isolators having a continuously decreasing tangent stiffness with increasing displacement, is presented. The parallel modeling concept is applied to discretize the continuously decreasing tangent stiffness function, thus allowing to simulate the dynamic behavior of seismic isolation bearings by putting linear elastic and nonlinear elastic-perfectly plastic elements in parallel. The mathematical model has been validated by comparing the experimental force-displacement hysteresis loops, obtained testing a helical wire rope isolator and a recycled rubber-fiber reinforced bearing, with those predicted numerically. Good agreement between the simulated and experimental results shows that the proposed model can be an effective numerical tool to predict the forcedisplacement relationship of seismic isolators within relatively large displacements. Compared to the widely used Bouc-Wen model, the proposed one allows to avoid the numerical solution of a first order ordinary nonlinear differential equation for each time step of a nonlinear time history analysis, thus reducing the computation effort, and requires the evaluation of only three model parameters from experimental tests, namely the initial tangent stiffness, the asymptotic tangent stiffness, and a parameter defining the transition from the initial to the asymptotic tangent stiffness.Keywords: base isolation, earthquake engineering, parallel elasto-plastic model, seismic isolators, softening hysteresis loops
Procedia PDF Downloads 28015914 A Posteriori Trading-Inspired Model-Free Time Series Segmentation
Authors: Plessen Mogens Graf
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Within the context of multivariate time series segmentation, this paper proposes a method inspired by a posteriori optimal trading. After a normalization step, time series are treated channelwise as surrogate stock prices that can be traded optimally a posteriori in a virtual portfolio holding either stock or cash. Linear transaction costs are interpreted as hyperparameters for noise filtering. Trading signals, as well as trading signals obtained on the reversed time series, are used for unsupervised channelwise labeling before a consensus over all channels is reached that determines the final segmentation time instants. The method is model-free such that no model prescriptions for segments are made. Benefits of proposed approach include simplicity, computational efficiency, and adaptability to a wide range of different shapes of time series. Performance is demonstrated on synthetic and real-world data, including a large-scale dataset comprising a multivariate time series of dimension 1000 and length 2709. Proposed method is compared to a popular model-based bottom-up approach fitting piecewise affine models and to a recent model-based top-down approach fitting Gaussian models and found to be consistently faster while producing more intuitive results in the sense of segmenting time series at peaks and valleys.Keywords: time series segmentation, model-free, trading-inspired, multivariate data
Procedia PDF Downloads 13615913 Preparedness is Overrated: Community Responses to Floods in a Context of (Perceived) Low Probability
Authors: Kim Anema, Matthias Max, Chris Zevenbergen
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For any flood risk manager the 'safety paradox' has to be a familiar concept: low probability leads to a sense of safety, which leads to more investments in the area, which leads to higher potential consequences: keeping the aggregated risk (probability*consequences) at the same level. Therefore, it is important to mitigate potential consequences apart from probability. However, when the (perceived) probability is so low that there is no recognizable trend for society to adapt to, addressing the potential consequences will always be the lagging point on the agenda. Preparedness programs fail because of lack of interest and urgency, policy makers are distracted by their day to day business and there's always a more urgent issue to spend the taxpayer's money on. The leading question in this study was how to address the social consequences of flooding in a context of (perceived) low probability. Disruptions of everyday urban life, large or small, can be caused by a variety of (un)expected things - of which flooding is only one possibility. Variability like this is typically addressed with resilience - and we used the concept of Community Resilience as the framework for this study. Drawing on face to face interviews, an extensive questionnaire and publicly available statistical data we explored the 'whole society response' to two recent urban flood events; the Brisbane Floods (AUS) in 2011 and the Dresden Floods (GE) in 2013. In Brisbane, we studied how the societal impacts of the floods were counteracted by both authorities and the public, and in Dresden we were able to validate our findings. A large part of the reactions, both public as institutional, to these two urban flood events were not fuelled by preparedness or proper planning. Instead, more important success factors in counteracting social impacts like demographic changes in neighborhoods and (non-)economic losses were dynamics like community action, flexibility and creativity from authorities, leadership, informal connections and a shared narrative. These proved to be the determining factors for the quality and speed of recovery in both cities. The resilience of the community in Brisbane was good, due to (i) the approachability of (local) authorities, (ii) a big group of ‘secondary victims’ and (iii) clear leadership. All three of these elements were amplified by the use of social media and/ or web 2.0 by both the communities and the authorities involved. The numerous contacts and social connections made through the web were fast, need driven and, in their own way, orderly. Similarly in Dresden large groups of 'unprepared', ad hoc organized citizens managed to work together with authorities in a way that was effective and speeded up recovery. The concept of community resilience is better fitted than 'social adaptation' to deal with the potential consequences of an (im)probable flood. Community resilience is built on capacities and dynamics that are part of everyday life and which can be invested in pre-event to minimize the social impact of urban flooding. Investing in these might even have beneficial trade-offs in other policy fields.Keywords: community resilience, disaster response, social consequences, preparedness
Procedia PDF Downloads 352