Search results for: sequential confidence estimation
1808 Influence of the Line Parameters in Transmission Line Fault Location
Authors: Marian Dragomir, Alin Dragomir
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In the paper, two fault location algorithms are presented for transmission lines which use the line parameters to estimate the distance to the fault. The first algorithm uses only the measurements from one end of the line and the positive and zero sequence parameters of the line, while the second one uses the measurements from both ends of the line and only the positive sequence parameters of the line. The algorithms were tested using a transmission grid transposed in MATLAB. In a first stage it was established a fault location base line, where the algorithms mentioned above estimate the fault locations using the exact line parameters. After that, the positive and zero sequence resistance and reactance of the line were calculated again for different ground resistivity values and then the fault locations were estimated again in order to compare the results with the base line results. The results show that the algorithm which uses the zero sequence impedance of the line is the most sensitive to the line parameters modifications. The other algorithm is less sensitive to the line parameters modification.Keywords: estimation algorithms, fault location, line parameters, simulation tool
Procedia PDF Downloads 3551807 Particle Swarm Optimization Based Method for Minimum Initial Marking in Labeled Petri Nets
Authors: Hichem Kmimech, Achref Jabeur Telmoudi, Lotfi Nabli
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The estimation of the initial marking minimum (MIM) is a crucial problem in labeled Petri nets. In the case of multiple choices, the search for the initial marking leads to a problem of optimization of the minimum allocation of resources with two constraints. The first concerns the firing sequence that could be legal on the initial marking with respect to the firing vector. The second deals with the total number of tokens that can be minimal. In this article, the MIM problem is solved by the meta-heuristic particle swarm optimization (PSO). The proposed approach presents the advantages of PSO to satisfy the two previous constraints and find all possible combinations of minimum initial marking with the best computing time. This method, more efficient than conventional ones, has an excellent impact on the resolution of the MIM problem. We prove through a set of definitions, lemmas, and examples, the effectiveness of our approach.Keywords: marking, production system, labeled Petri nets, particle swarm optimization
Procedia PDF Downloads 1781806 Terrorism and National Development: A Critique of Its Aftermath on Educational Attainment
Authors: David Chapola Nggada
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Although the concept of terrorism is not a new phenomenon to Nigeria, the protracted terrorist activities experiencing in the north-eastern part of the country since 2009, had left an indelible mark on virtually every aspects of lives whether directly or indirectly, particularly the educational sector. Indeed, since the abduction of over 200 schoolgirls at Chibok in 2014 by the insurgence, education had witnessed a setback as most school remains closed for sometimes. The aftermath of this development on education and its future multiplier effect on national development is a source of concern. Consequently, this paper is designed to examine the consequences of terrorism on educational attainment and national development among the Chibok community of Borno State. The technique employed involves a mixture of both qualitative and quantitative research work on a sample size of 79 secondary school students currently displaced from Chibok, Damboa and Askira-Uba, now residing as internally displaced persons(IDPs) in Biu, Gombe, Maiduguri. A random sample technique is used. Structured and semi-unstructured questionnaire were administered. The result shows that, a significant number of students over these years, lacked access to education and this posed a great danger to national development. Recommendations towards reinvigorating education as a panacea to social, economic cum political vices were articulated. Concerted effort should be made to create confidence in the community.Keywords: education, effect, terrorism, national, development
Procedia PDF Downloads 2631805 Estimation of Location and Scale Parameters of Extended Exponential Distribution Based on Record Statistics
Authors: E. Krishna
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An Extended form of exponential distribution using Marshall and Olkin method is introduced.The location scale family of these distributions is considered. For location scale free family, exact expressions for single and product moments of upper record statistics are derived. The mean, variance and covariance of record values are computed for various values of the shape parameter. Using these the BLUE's of location and scale parameters are derived.The variances and covariance of estimates are obtained.Through Monte Carlo simulation the condence intervals for location and scale parameters are constructed.The Best liner unbiased Predictor (BLUP) of future records are also discussed.Keywords: BLUE, BLUP, condence interval, Marshall-Olkin distribution, Monte Carlo simulation, prediction of future records, record statistics
Procedia PDF Downloads 4171804 Menopause Cultural Research: A Comparative Study of National and Diasporic Chinese Menopausal Women’s Perceptions and Lived Experience of Menopause
Authors: Yilin Wang, Ayumi Goto
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Although most females will experience menopause due to social value habits of cultural factors, some Chinese women may lack the confidence to talk about the problems they are experiencing while going through menopause. Also, sometimes the inappropriateness of medical terminology leads to panic when women face the symptoms associated with menopause. On top of that, when women avoid discussing menopause as a topic, others are less likely to pay attention to the needs of menopausal women as their bodies change. This research will compare the experience of Chinese menopausal women and diasporic Chinese women's perceptions of menopause. A qualitative study will be conducted by collecting and analyzing experiences and perceptions to compare differences in women's perceptions of menopause, considering cultural and social factors. In addition, the study will gather information on the differences in the conceptualization of menopause between the Chinese and Canadian medical fields. Co-design sessions will be held to establish how to bring menopause to the attention of people other than women. Furthermore, a support network for menopause women will be created through these co-design sessions. It is hoped that this research will contribute to a proper understanding of menopause and provide support for Chinese women. This research is built upon feminist standpoint theory and inclusive design theory. The results of this study will be presented in this paper.Keywords: menopause, feminist standpoint theory, Chinese national & diasporic women, inclusive design
Procedia PDF Downloads 1071803 Alumni Experiences of How Their Undergraduate Medical Education Instilled and Fostered a Commitment to Community-Based Work in Later Life: A Sequential Exploratory Mixed-Methods Study
Authors: Harini Aiyer, Kalyani Premkumar
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Health professionals are the key players who can help achieve the goals of population health equity. Social accountability (SA) of health professionals emphasizes their role in addressing issues of equity in the population they serve. Therefore, health professional education must focus on instilling SA in health professionals. There is limited literature offering a longitudinal perspective of how students sustain the practice of SA in later life. This project aims to identify the drivers of social accountability among physicians. This study employed an exploratory mixed methods design (QUAL-> Quant) to explore alumni perceptions and experiences. The qualitative data, collected via 20 in-depth, semi-structured interviews, provided an understanding of the perceptions of the alumni regarding the influence of their undergraduate learning environment on their SA. This was followed by a quantitative portion -a questionnaire designed from the themes identified from the qualitative data. Emerging themes from the study highlighted community-centered education and a focus on social and preventative medicine in both curricular and non-curricular facilitators of SA among physicians. Curricular components included opportunities to engage with the community, such as roadside clinics, community-orientation programs, and postings at a secondary hospital. Other facilitators that emerged were the faculty leading by example, a subsidized fee structure, and a system that prepared students for practice in rural and remote areas. The study offers a fresh perspective and dimension on how SA is addressed by medical schools. The findings may be adapted by medical schools to understand how their own SA initiatives have been sustained among physicians over the long run.Keywords: community-based work, global health, health education, medical education, providing health in remote areas, social accountability
Procedia PDF Downloads 801802 Strategies to Enhance Compliance of Health and Safety Standards at the Selected Mining Industries in Limpopo Province, South Africa: Occupational Health Nurse’s Perspective
Authors: Livhuwani Muthelo
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The health and safety of the miners in the South African mining industry are guided by the regulations and standards which are anticipated to promote a healthy work environment and fatalities. It is of utmost importance for the miners to comply with these regulations/standards to protect themselves from potential occupational health and safety risks, accidents, and fatalities. The purpose of this study was to develop and validate strategies to enhance compliance with the Health and safety standards within the mining industries of Limpopo province in South Africa. A mixed-method exploratory sequential research design was adopted. The population consisted of 5350 miners. Purposive sampling was used to select the participants in the qualitative strand and stratified random sampling in the quantitative strand. Semi-structured interviews were conducted among the occupational health nurse practitioners and the health and safety team. Thematic analysis was used to generate an understanding of the interviews. In the quantitative strand, a survey was conducted using a self-administered questionnaire. Data were analysed using SPSS version 26.0. A descriptive statistical test was used in the analysis of data including frequencies, means, and standard deviation. Cronbach's alpha test was used to measure internal consistency. The integrated results revealed that there are diverse experiences related to health and safety standards compliance among the mineworkers. The main findings were challenges related to leadership compliance and also related to the cost of maintaining safety, Miner's behavior-related challenges; the impact of non-compliance on the overall health of the miners was also described, the conflict between production and safety. Health and safety compliance is not just mere compliance with regulations and standards but a culture that warrants the miners and organization to take responsibility for their behavior and actions towards health and safety. Thus taking responsibility for your well-being and other miners.Keywords: perceptions, compliance, health and safety, legislation, standards, miners
Procedia PDF Downloads 1041801 Poisoning Admission in Pediatrics Benghazi Hospital in Libya: Three Years Review of Medical Record
Authors: Mudafara Bengleil
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Estimation of the magnitude and causes of poisoning was the objective of the current study. A retrospective study of medical records of all poisoning children admitted to Benghazi Children Hospital in Libya from January 2008 up to December 2010. Number of children admitted was 244; the age ranged from less than one to 13 years old. Most of cases were admitted with mild symptom and the majority of them were boys. Only few cases admitted to intensive care unit and there was no mortality recorded through the period of study. Age group 1 to 3 years (50.8%) had the highest frequency of admission and the peak of admission was during summer. The most common cause of admission was due to ingestion of medication (53.69%), House hold product exposure (26.64%) was the second causes of admission while, 19.67% of admissions were due to Food poisoning. Almost all admitted cases were accidental and medicines were the most consumed substances in addition, improper storage of toxic agents were the first risk factor of poisoning. Present results indicated that, children poisoning seems to be a common pediatric care problem which need to control and prevent.Keywords: poisoning, children, hospital, medical
Procedia PDF Downloads 4211800 Stability of Pump Station Cavern in Chagrin Shale with Time
Authors: Mohammad Moridzadeh, Mohammad Djavid, Barry Doyle
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An assessment of the long-term stability of a cavern in Chagrin shale excavated by the sequential excavation method was performed during and after construction. During the excavation of the cavern, deformations of rock mass were measured at the surface of excavation and within the rock mass by surface and deep measurement instruments. Rock deformations were measured during construction which appeared to result from the as-built excavation sequence that had potentially disturbed the rock and its behavior. Also some additional time dependent rock deformations were observed during and post excavation. Several opinions have been expressed to explain this time dependent deformation including stress changes induced by excavation, strain softening (or creep) in the beddings with and without clay and creep of the shaley rock under compressive stresses. In order to analyze and replicate rock behavior observed during excavation, including current and post excavation elastic, plastic, and time dependent deformation, Finite Element Analysis (FEA) was performed. The analysis was also intended to estimate long term deformation of the rock mass around the excavation. Rock mass behavior including time dependent deformation was measured by means of rock surface convergence points, MPBXs, extended creep testing on the long anchors, and load history data from load cells attached to several long anchors. Direct creep testing of Chagrin Shale was performed on core samples from the wall of the Pump Room. Results of these measurements were used to calibrate the FEA of the excavation. These analyses incorporate time dependent constitutive modeling for the rock to evaluate the potential long term movement in the roof, walls, and invert of the cavern. The modeling was performed due to the concerns regarding the unanticipated behavior of the rock mass as well as the forecast of long term deformation and stability of rock around the excavation.Keywords: Cavern, Chagrin shale, creep, finite element.
Procedia PDF Downloads 3511799 Mixed Treatment (Physical-Chemical and Biological) of Ouled Fayet Landfill Leachates
Authors: O. Balamane-Zizi, L. M. Rouidi, A. Boukhrissa, N. Daas, H. Ait-amar
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The objective of this study was to test the possibility of a mixed treatment (physical-chemical and biological) of Ouled Fayet leachates which date of 10 years and has a large fraction of hard COD that can be reduced by coagulation-flocculation. Previous batch tests showed the possibility of applying the physical-chemical and biological treatments separately; the removal efficiencies obtained in this case were not interesting. We propose, therefore, to test the possibility of a combined treatment, in order to improve the quality of the leachates. Estimation of the treatment’s effectiveness was done by analysis of some pollution parameters such as COD, suspended solids, and heavy metals (particularly iron and nickel). The main results obtained after the combination of treatments, show reduction rate of about 63% for COD, 73% for suspended solids and 80% for iron and nickel. We also noted an improvement in the turbidity of treated leachates.Keywords: landfill leachates, COD, physical-chemical treatment, biological treatment
Procedia PDF Downloads 4731798 Measuring Banking Risk
Authors: Mike Tsionas
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The paper develops new indices of financial stability based on an explicit model of expected utility maximization by financial institutions subject to the classical technology restrictions of neoclassical production theory. The model can be estimated using standard econometric techniques, like GMM for dynamic panel data and latent factor analysis for the estimation of co-variance matrices. An explicit functional form for the utility function is not needed and we show how measures of risk aversion and prudence (downside risk aversion) can be derived and estimated from the model. The model is estimated using data for Eurozone countries and we focus particularly on (i) the use of the modeling approach as an “early warning mechanism”, (ii) the bank- and country-specific estimates of risk aversion and prudence (downside risk aversion), and (iii) the derivation of a generalized measure of risk that relies on loan-price uncertainty.Keywords: financial stability, banking, expected utility maximization, sub-prime crisis, financial crisis, eurozone, PIIGS
Procedia PDF Downloads 3491797 A Perspective on Teaching Mathematical Concepts to Freshman Economics Students Using 3D-Visualisations
Authors: Muhammad Saqib Manzoor, Camille Dickson-Deane, Prashan Karunaratne
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Cobb-Douglas production (utility) function is a fundamental function widely used in economics teaching and research. The key reason is the function's characteristics to describe the actual production using inputs like labour and capital. The characteristics of the function like returns to scale, marginal, and diminishing marginal productivities are covered in the introductory units in both microeconomics and macroeconomics with a 2-dimensional static visualisation of the function. However, less insight is provided regarding three-dimensional surface, changes in the curvature properties due to returns to scale, the linkage of the short-run production function with its long-run counterpart and marginal productivities, the level curves, and the constraint optimisation. Since (freshman) learners have diverse prior knowledge and cognitive skills, the existing “one size fits all” approach is not very helpful. The aim of this study is to bridge this gap by introducing technological intervention with interactive animations of the three-dimensional surface and sequential unveiling of the characteristics mentioned above using Python software. A small classroom intervention has helped students enhance their analytical and visualisation skills towards active and authentic learning of this topic. However, to authenticate the strength of our approach, a quasi-Delphi study will be conducted to ask domain-specific experts, “What value to the learning process in economics is there using a 2-dimensional static visualisation compared to using a 3-dimensional dynamic visualisation?’ Here three perspectives of the intervention were reviewed by a panel comprising of novice students, experienced students, novice instructors, and experienced instructors in an effort to determine the learnings from each type of visualisations within a specific domain of knowledge. The value of this approach is key to suggesting different pedagogical methods which can enhance learning outcomes.Keywords: cobb-douglas production function, quasi-Delphi method, effective teaching and learning, 3D-visualisations
Procedia PDF Downloads 1451796 Localization Mobile Beacon Using RSSI
Authors: Sallama Resen, Celal Öztürk
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Distance estimation between tow nodes has wide scope of surveillance and tracking applications. This paper suggests a Bluetooth Low Energy (BLE) technology as a media for transceiver and receiver signal in small indoor areas. As an example, BLE communication technologies used in child safety domains. Local network is designed to detect child position in indoor school area consisting Mobile Beacons (MB), Access Points (AP) and Smart Phones (SP) where MBs stuck in children’s shoes as wearable sensors. This paper presents a technique that can detect mobile beacons’ position and help finding children’s location within dynamic environment. By means of bluetooth beacons that are attached to child’s shoes, the distance between the MB and teachers SP is estimated with an accuracy of less than one meter. From the simulation results, it is shown that high accuracy of position coordinates are achieved for multi-mobile beacons in different environments.Keywords: bluetooth low energy, child safety, mobile beacons, received signal strength
Procedia PDF Downloads 3461795 Identification of Deposition Sequences of the Organic Content of Lower Albian-Cenomanian Age in Northern Tunisia: Correlation between Molecular and Stratigraphic Fossils
Authors: Tahani Hallek, Dhaou Akrout, Riadh Ahmadi, Mabrouk Montacer
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The present work is an organic geochemical study of the Fahdene Formation outcrops at the Mahjouba region belonging to the Eastern part of the Kalaat Senan structure in northwestern Tunisia (the Kef-Tedjerouine area). The analytical study of the organic content of the samples collected, allowed us to point out that the Formation in question is characterized by an average to good oil potential. This fossilized organic matter has a mixed origin (type II and III), as indicated by the relatively high values of hydrogen index. This origin is confirmed by the C29 Steranes abundance and also by tricyclic terpanes C19/(C19+C23) and tetracyclic terpanes C24/(C24+C23) ratios, that suggest a marine environment of deposit with high plants contribution. We have demonstrated that the heterogeneity of organic matter between the marine aspect, confirmed by the presence of foraminifera, and the continental contribution, is the result of an episodic anomaly in relation to the sequential stratigraphy. Given that the study area is defined as an outer platform forming a transition zone between a stable continental domain to the south and a deep basin to the north, we have explained the continental contribution by successive forced regressions, having blocked the albian transgression, allowing the installation of the lowstand system tracts. This aspect is represented by the incised valleys filling, in direct contact with the pelagic and deep sea facies. Consequently, the Fahdene Formation, in the Kef-Tedjerouine area, consists of transgressive system tracts (TST) brutally truncated by extras of continental progradation; resulting in a mixed influence deposition having retained a heterogeneous organic material.Keywords: molecular geochemistry, biomarkers, forced regression, deposit environment, mixed origin, Northern Tunisia
Procedia PDF Downloads 2491794 Robot Movement Using the Trust Region Policy Optimization
Authors: Romisaa Ali
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The Policy Gradient approach is one of the deep reinforcement learning families that combines deep neural networks (DNN) with reinforcement learning RL to discover the optimum of the control problem through experience gained from the interaction between the robot and its surroundings. In contrast to earlier policy gradient algorithms, which were unable to handle these two types of error because of over-or under-estimation introduced by the deep neural network model, this article will discuss the state-of-the-art SOTA policy gradient technique, trust region policy optimization (TRPO), by applying this method in various environments compared to another policy gradient method, the Proximal Policy Optimization (PPO), to explain their robust optimization, using this SOTA to gather experience data during various training phases after observing the impact of hyper-parameters on neural network performance.Keywords: deep neural networks, deep reinforcement learning, proximal policy optimization, state-of-the-art, trust region policy optimization
Procedia PDF Downloads 1691793 Nonparametric Specification Testing for the Drift of the Short Rate Diffusion Process Using a Panel of Yields
Authors: John Knight, Fuchun Li, Yan Xu
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Based on a new method of the nonparametric estimator of the drift function, we propose a consistent test for the parametric specification of the drift function in the short rate diffusion process using observations from a panel of yields. The test statistic is shown to follow an asymptotic normal distribution under the null hypothesis that the parametric drift function is correctly specified, and converges to infinity under the alternative. Taking the daily 7-day European rates as a proxy of the short rate, we use our test to examine whether the drift of the short rate diffusion process is linear or nonlinear, which is an unresolved important issue in the short rate modeling literature. The testing results indicate that none of the drift functions in this literature adequately captures the dynamics of the drift, but nonlinear specification performs better than the linear specification.Keywords: diffusion process, nonparametric estimation, derivative security price, drift function and volatility function
Procedia PDF Downloads 3681792 Special Case of Trip Distribution Model and Its Use for Estimation of Detailed Transport Demand in the Czech Republic
Authors: Jiri Dufek
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The national model of the Czech Republic has been modified in a detailed way to get detailed travel demand in the municipality level (cities, villages over 300 inhabitants). As a technique for this detailed modelling, three-dimensional procedure for calibrating gravity models, was used. Besides of zone production and attraction, which is usual in gravity models, the next additional parameter for trip distribution was introduced. Usually it is called by “third dimension”. In the model, this parameter is a demand between regions. The distribution procedure involved calculation of appropriate skim matrices and its multiplication by three coefficients obtained by iterative balancing of production, attraction and third dimension. This type of trip distribution was processed in R-project and the results were used in the Czech Republic transport model, created in PTV Vision. This process generated more precise results in local level od the model (towns, villages)Keywords: trip distribution, three dimension, transport model, municipalities
Procedia PDF Downloads 1301791 Comparative Analysis of Competitive State Anxiety among Team Sport and Individual Sport Athletes in Iran
Authors: Hossein Soltani, Zahra Hojati, Seyed Reza Attarzadeh Hossini
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Anxiety levels before and during competition are not clear due to conflicting findings; various athletes have reported different levels of anxiety from much too low. With respect to the fact that every sport field has its own special nature, and the lack of a comprehensive theory in this field made the author to compare competitive state anxiety among team sport and individual sport athletes in Iran. The sample included 120 male athletes, 60 athletes in individual sports (taekwondo, karate, and wrestling) and 60 athletes in team sports (volleyball, basketball, futsal). All participants in this study were regularly competing at the super leagues and regional level. The research instrument employed was the Persian version of the Competitive State Anxiety Inventory-2. This inventory was distributed among the subjects about 30 minutes before the first competition. Finally, using one-way ANOVA data was analyzed. The results indicated that the mean score of cognitive and somatic anxiety among individual sport athletes was higher than that of team sport athletes (P<0.05). Self-confidence levels of individual sports athletes was higher than that of team sports athletes but the difference was not significant (P >0.05). It seems the being part of a team alleviates some of the pressure experienced by those who compete alone. Conclusion: Individual sport athletes may be more exposed to evaluation and more engaged in their own skills and abilities than team sport athletes given that responsibility for performance is not distributed across several performers.Keywords: competitive state anxiety, cognitive anxiety, somatic anxiety, team sports, individual sports
Procedia PDF Downloads 5761790 Estimation of PM2.5 Emissions and Source Apportionment Using Receptor and Dispersion Models
Authors: Swetha Priya Darshini Thammadi, Sateesh Kumar Pisini, Sanjay Kumar Shukla
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Source apportionment using Dispersion model depends primarily on the quality of Emission Inventory. In the present study, a CMB receptor model has been used to identify the sources of PM2.5, while the AERMOD dispersion model has been used to account for missing sources of PM2.5 in the Emission Inventory. A statistical approach has been developed to quantify the missing sources not considered in the Emission Inventory. The inventory of each grid was improved by adjusting emissions based on road lengths and deficit in measured and modelled concentrations. The results showed that in CMB analyses, fugitive sources - soil and road dust - contribute significantly to ambient PM2.5 pollution. As a result, AERMOD significantly underestimated the ambient air concentration at most locations. The revised Emission Inventory showed a significant improvement in AERMOD performance which is evident through statistical tests.Keywords: CMB, GIS, AERMOD, PM₂.₅, fugitive, emission inventory
Procedia PDF Downloads 3401789 Developing a Multi-Modal Choking Intervention
Authors: R. Maher, D. Marchant, F. Fazel
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The initial aim of the study was to capitalize on the depth of athletes’ and coaches’ knowledge pertaining to the phenomenon of choking in basketball, free-throw shooting in particular, from an ‘insiders’ perspective. The findings of this study have developed a deeper understanding of how basketball players and coaches deal with choking and potentially contribute new knowledge relevant to designing useful interventions for alleviating choking. A key element was thus, knowledge, transfer, and exchange (KTE). KTE is the process of acquiring, developing, sharing and applying knowledge. Semi-structured interviews were conducted employing a composed sample of eight elite basketball players and four elite coaches who have been experiencing the choking episode previously. All interviews have been digitally recorded and later transcribed verbatim. Then the interviews have been content analyzed. Participants of the present study have provided useful information regarding the underlying mechanisms and antecedents of choking and also suggested applicable antidotes to conquer the phenomenon of choking. According to the results of the present study, self-confidence, mental and physical preparation, and coping styles should be considered as influential factors in athletes’ performance under pressure. Moreover, using all noteworthy information and preventative strategies suggested by participants of the present study, an effective multi-modal intervention has been introduced that should be taken into account by sports psychologists, coaches and athletes.Keywords: anxiety, basketball, choking, free-throw shooting, psychological intervention
Procedia PDF Downloads 2621788 Short and Long Crack Growth Behavior in Ferrite Bainite Dual Phase Steels
Authors: Ashok Kumar, Shiv Brat Singh, Kalyan Kumar Ray
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There is growing awareness to design steels against fatigue damage Ferrite martensite dual-phase steels are known to exhibit favourable mechanical properties like good strength, ductility, toughness, continuous yielding, and high work hardening rate. However, dual-phase steels containing bainite as second phase are potential alternatives for ferrite martensite steels for certain applications where good fatigue property is required. Fatigue properties of dual phase steels are popularly assessed by the nature of variation of crack growth rate (da/dN) with stress intensity factor range (∆K), and the magnitude of fatigue threshold (∆Kth) for long cracks. There exists an increased emphasis to understand not only the long crack fatigue behavior but also short crack growth behavior of ferrite bainite dual phase steels. The major objective of this report is to examine the influence of microstructures on the short and long crack growth behavior of a series of developed dual-phase steels with varying amounts of bainite and. Three low carbon steels containing Nb, Cr and Mo as microalloying elements steels were selected for making ferrite-bainite dual-phase microstructures by suitable heat treatments. The heat treatment consisted of austenitizing the steel at 1100°C for 20 min, cooling at different rates in air prior to soaking these in a salt bath at 500°C for one hour, and finally quenching in water. Tensile tests were carried out on 25 mm gauge length specimens with 5 mm diameter using nominal strain rate 0.6x10⁻³ s⁻¹ at room temperature. Fatigue crack growth studies were made on a recently developed specimen configuration using a rotating bending machine. The crack growth was monitored by interrupting the test and observing the specimens under an optical microscope connected to an Image analyzer. The estimated crack lengths (a) at varying number of cycles (N) in different fatigue experiments were analyzed to obtain log da/dN vs. log °∆K curves for determining ∆Kthsc. The microstructural features of these steels have been characterized and their influence on the near threshold crack growth has been examined. This investigation, in brief, involves (i) the estimation of ∆Kthsc and (ii) the examination of the influence of microstructure on short and long crack fatigue threshold. The maximum fatigue threshold values obtained from short crack growth experiments on various specimens of dual-phase steels containing different amounts of bainite are found to increase with increasing bainite content in all the investigated steels. The variations of fatigue behavior of the selected steel samples have been explained with the consideration of varying amounts of the constituent phases and their interactions with the generated microstructures during cyclic loading. Quantitative estimation of the different types of fatigue crack paths indicates that the propensity of a crack to pass through the interfaces depends on the relative amount of the microstructural constituents. The fatigue crack path is found to be predominantly intra-granular except for the ones containing > 70% bainite in which it is predominantly inter-granular.Keywords: bainite, dual phase steel, fatigue crack growth rate, long crack fatigue threshold, short crack fatigue threshold
Procedia PDF Downloads 2041787 Estimating Tree Height and Forest Classification from Multi Temporal Risat-1 HH and HV Polarized Satellite Aperture Radar Interferometric Phase Data
Authors: Saurav Kumar Suman, P. Karthigayani
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In this paper the height of the tree is estimated and forest types is classified from the multi temporal RISAT-1 Horizontal-Horizontal (HH) and Horizontal-Vertical (HV) Polarised Satellite Aperture Radar (SAR) data. The novelty of the proposed project is combined use of the Back-scattering Coefficients (Sigma Naught) and the Coherence. It uses Water Cloud Model (WCM). The approaches use two main steps. (a) Extraction of the different forest parameter data from the Product.xml, BAND-META file and from Grid-xxx.txt file come with the HH & HV polarized data from the ISRO (Indian Space Research Centre). These file contains the required parameter during height estimation. (b) Calculation of the Vegetation and Ground Backscattering, Coherence and other Forest Parameters. (c) Classification of Forest Types using the ENVI 5.0 Tool and ROI (Region of Interest) calculation.Keywords: RISAT-1, classification, forest, SAR data
Procedia PDF Downloads 4071786 Variation of Phytoplankton Biomass in the East China Sea Based on MODIS Data
Authors: Yumei Wu, Xiaoyan Dang, Shenglong Yang, Shengmao Zhang
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The East China Sea is one of four main seas in China, where there are many fishery resources. Some important fishing grounds, such as Zhousan fishing ground important to society. But the eco-environment is destroyed seriously due to the rapid developing of industry and economy these years. In this paper, about twenty-year satellite data from MODIS and the statistical information of marine environment from the China marine environmental quality bulletin were applied to do the research. The chlorophyll-a concentration data from MODIS were dealt with in the East China Sea and then used to analyze the features and variations of plankton biomass in recent years. The statistics method was used to obtain their spatial and temporal features. The plankton biomass in the Yangtze River estuary and the Taizhou region were highest. The high phytoplankton biomass usually appeared between the 88th day to the 240th day (end-March - August). In the peak time of phytoplankton blooms, the Taizhou islands was the earliest, and the South China Sea was the latest. The intensity and period of phytoplankton blooms were connected with the global climate change. This work give us confidence to use satellite data to do more researches about the China Sea, and it also provides some help for us to know about the eco-environmental variation of the East China Sea and regional effect from global climate change.Keywords: the East China Sea, phytoplankton biomass, temporal and spatial variation, phytoplankton bloom
Procedia PDF Downloads 3291785 Axle Load Estimation of Moving Vehicles Using BWIM Technique
Authors: Changgil Lee, Seunghee Park
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Although vehicle driving test for the development of BWIM system is necessary, but it needs much cost and time in addition application of various driving condition. Thus, we need the numerical-simulation method resolving the cost and time problems of vehicle driving test and the way of measuring response of bridge according to the various driving condition. Using the precision analysis model reflecting the dynamic characteristic is contributed to increase accuracy in numerical simulation. In this paper, we conduct a numerical simulation to apply precision analysis model, which reflects the dynamic characteristic of bridge using Bridge Weigh-in-Motion technique and suggest overload vehicle enforcement technology using precision analysis model.Keywords: bridge weigh-in-motion(BWIM) system, precision analysis model, dynamic characteristic of bridge, numerical simulation
Procedia PDF Downloads 2921784 Optical Flow Localisation and Appearance Mapping (OFLAAM) for Long-Term Navigation
Authors: Daniel Pastor, Hyo-Sang Shin
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This paper presents a novel method to use optical flow navigation for long-term navigation. Unlike standard SLAM approaches for augmented reality, OFLAAM is designed for Micro Air Vehicles (MAV). It uses an optical flow camera pointing downwards, an IMU and a monocular camera pointing frontwards. That configuration avoids the expensive mapping and tracking of the 3D features. It only maps these features in a vocabulary list by a localization module to tackle the loss of the navigation estimation. That module, based on the well-established algorithm DBoW2, will be also used to close the loop and allow long-term navigation in confined areas. That combination of high-speed optical flow navigation with a low rate localization algorithm allows fully autonomous navigation for MAV, at the same time it reduces the overall computational load. This framework is implemented in ROS (Robot Operating System) and tested attached to a laptop. A representative scenarios is used to analyse the performance of the system.Keywords: vision, UAV, navigation, SLAM
Procedia PDF Downloads 6061783 The Competitive Newsvendor Game with Overestimated Demand
Authors: Chengli Liu, C. K. M. Lee
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The tradition competitive newsvendor game assumes decision makers are rational. However, there are behavioral biases when people make decisions, such as loss aversion, mental accounting and overconfidence. Overestimation of a subject’s own performance is one type of overconfidence. The objective of this research is to analyze the impact of the overestimated demand in the newsvendor competitive game with two players. This study builds a competitive newsvendor game model where newsvendors have private information of their demands, which is overestimated. At the same time, demands of each newsvendor forecasted by a third party institution are available. This research shows that the overestimation leads to demand steal effect, which reduces the competitor’s order quantity. However, the overall supply of the product increases due to overestimation. This study illustrates the boundary condition for the overestimated newsvendor to have the equilibrium order drop due to the demand steal effect from the other newsvendor. A newsvendor who has higher critical fractile will see its equilibrium order decrease with the drop of estimation level from the other newsvendor.Keywords: bias, competing newsvendor, Nash equilibrium, overestimation
Procedia PDF Downloads 2611782 Education For Social Justice: A Comparative Study of University Teachers' Conceptions and Practice
Authors: Digby Warren, Jiri Kropac
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This comparative study seeks to develop a deeper understanding of what is meant by “education for social justice” (ESJ) - an aspiration articulated by universities, though often without much definition. The research methodology involved thematic analysis of data from in-depth interviews with academics (voluntary participants) in different disciplines and institutions in the UK, Czech Republic and other EU countries. The interviews explored lecturers’ conceptions of ESJ, their practice of it, and associated challenges and enabling factors. Main findings are that ESJ is construed as provision of equitable and conscientising education opportunities that run across the whole higher education (HE) journey, from widening access to HE to stimulating critical learning and awareness that can empower graduates to transform their lives and societies. Teaching practice featured study of topics related to social justice; collaborative and creative learning activities, and assignments offering choice and connection to students’ realities. Student responses could be mixed, occasionally resistant, but mostly positive in terms of gaining increased confidence and awareness of equality and social responsibility. Influences at the macro, meso and mico level could support or limit scope for ESJ. Overall, the study highlights the strong, values-based commitment of HE teachers to facilitating student learning engagement, wellbeing and development towards building a better world.Keywords: higher education, social justice, inclusivity, diversity
Procedia PDF Downloads 751781 Diffusion Adaptation Strategies for Distributed Estimation Based on the Family of Affine Projection Algorithms
Authors: Mohammad Shams Esfand Abadi, Mohammad Ranjbar, Reza Ebrahimpour
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This work presents the distributed processing solution problem in a diffusion network based on the adapt then combine (ATC) and combine then adapt (CTA)selective partial update normalized least mean squares (SPU-NLMS) algorithms. Also, we extend this approach to dynamic selection affine projection algorithm (DS-APA) and ATC-DS-APA and CTA-DS-APA are established. The purpose of ATC-SPU-NLMS and CTA-SPU-NLMS algorithm is to reduce the computational complexity by updating the selected blocks of weight coefficients at every iteration. In CTA-DS-APA and ATC-DS-APA, the number of the input vectors is selected dynamically. Diffusion cooperation strategies have been shown to provide good performance based on these algorithms. The good performance of introduced algorithm is illustrated with various experimental results.Keywords: selective partial update, affine projection, dynamic selection, diffusion, adaptive distributed networks
Procedia PDF Downloads 7071780 Looking for a Connection between Oceanic Regions with Trends in Evaporation with Continental Ones with Trends in Precipitation through a Lagrangian Approach
Authors: Raquel Nieto, Marta Vázquez, Anita Drumond, Luis Gimeno
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One of the hot spots of climate change is the increment of ocean evaporation. The best estimation of evaporation, OAFlux data, shows strong increasing trends in evaporation from the oceans since 1978, with peaks during the hemispheric winter and strongest along the paths of the global western boundary currents and any inner Seas. The transport of moisture from oceanic sources to the continents is the connection between evaporation from the ocean and precipitation over the continents. A key question is to try to relate evaporative source regions over the oceans where trends have occurred in the last decades with their sinks over the continents to check if there have been also any trends in the precipitation amount or its characteristics. A Lagrangian approach based on FLEXPART and ERA-interim data is used to establish this connection. The analyzed period was 1980 to 2012. Results show that there is not a general pattern, but a significant agreement was found in important areas of climate interest.Keywords: ocean evaporation, Lagrangian approaches, contiental precipitation, Europe
Procedia PDF Downloads 2561779 The Impact of a Leadership Change on Individuals' Behaviour and Incentives: Evidence from the Top Tier Italian Football League
Authors: Kaori Narita, Juan de Dios Tena Horrillo, Claudio Detotto
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Decisions on replacement of leaders are of significance and high prevalence in any organization, and concerns many of its stakeholders, whether it is a leader in a political party or a CEO of a firm, as indicated by high media coverage of such events. This merits an investigation into the consequences and implications of a leadership change on the performances and behavior of organizations and their workers. Sport economics provides a fruitful field to explore these issues due to the high frequencies of managerial changes in professional sports clubs and the transparency and regularity of observations of team performance and players’ abilities. Much of the existing research on managerial change focuses on how this affects the performance of an organization. However, there is scarcely attention paid to the consequences of such events on the behavior of individuals within the organization. Changes in behavior and attitudes of a group of workers due to a managerial change could be of great interest in management science, psychology, and operational research. On the other hand, these changes cannot be observed in the final outcome of the organization, as this is affected by many other unobserved shocks, for example, the stress level of workers with the need to deal with a difficult situation. To fill this gap, this study shows the first attempt to evaluate the impact of managerial change on players’ behaviors such as attack intensity, aggressiveness, and efforts. The data used in this study is from the top tier Italian football league (“Serie A”), where an average of 13 within season replacements of head coaches were observed over the period of seasons from 2000/2001 to 2017/18. The preliminary estimation employs Pooled Ordinary Least Square (POLS) and club-season Fixed Effect (FE) in order to assess the marginal effect of having a new manager on the number of shots, corners and red/yellow cards after controlling for a home-field advantage, ex ante abilities and current positions in the league of a team and their opponent. The results from this preliminary estimation suggest that the teams do not show a significant difference in their behaviors before and after the managerial change. To build on these preliminary results, other methods, including propensity score matching and non-linear model estimates, will be used. Moreover, the study will further investigate these issues by considering other measurements of attack intensity, aggressiveness, and efforts, such as possessions, a number of fouls and the athletic performance of players, respectively. Finally, the study is going to investigate whether these results vary over the characteristics of a new head coach, for example, their age and experience as a manager and a player. Thus far, this study suggests that certain behaviours of individuals in an organisation are not immediately affected by a change in leadership. To confirm this preliminary finding and lead to a more solid conclusion, further investigation will be conducted in the aforementioned manner, and the results will be elaborated in the conference.Keywords: behaviour, effort, manager characteristics, managerial change, sport economics
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