Search results for: stage performance
15169 Method for Tuning Level Control Loops Based on Internal Model Control and Closed Loop Step Test Data
Authors: Arnaud Nougues
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This paper describes a two-stage methodology derived from internal model control (IMC) for tuning a proportional-integral-derivative (PID) controller for levels or other integrating processes in an industrial environment. Focus is the ease of use and implementation speed which are critical for an industrial application. Tuning can be done with minimum effort and without the need for time-consuming open-loop step tests on the plant. The first stage of the method applies to levels only: the vessel residence time is calculated from equipment dimensions and used to derive a set of preliminary proportional-integral (PI) settings with IMC. The second stage, re-tuning in closed-loop, applies to levels as well as other integrating processes: a tuning correction mechanism has been developed based on a series of closed-loop simulations with model errors. The tuning correction is done from a simple closed-loop step test and the application of a generic correlation between observed overshoot and integral time correction. A spin-off of the method is that an estimate of the vessel residence time (levels) or open-loop process gain (other integrating process) is obtained from the closed-loop data.Keywords: closed-loop model identification, IMC-PID tuning method, integrating process control, on-line PID tuning adaptation
Procedia PDF Downloads 21815168 Performance Comparison of Space-Time Block and Trellis Codes under Rayleigh Channels
Authors: Jing Qingfeng, Wu Jiajia
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Due to the crowded orbits and shortage of frequency resources, utilizing of MIMO technology to improve spectrum efficiency and increase the capacity has become a necessary trend of broadband satellite communication. We analyze the main influenced factors and compare the BER performance of space-time block code (STBC) scheme and space-time trellis code (STTC) scheme. This paper emphatically studies the bit error rate (BER) performance of STTC and STBC under Rayleigh channel. The main emphasis is placed on the effects of the factors, such as terminal environment and elevation angles, on the BER performance of STBC and STTC schemes. Simulation results indicate that performance of STTC under Rayleigh channel is obviously improved with the increasing of transmitting and receiving antennas numbers, but the encoder state has little impact on the performance. Under Rayleigh channel, performance of Alamouti code is better than that of STTC.Keywords: MIMO, space time block code (STBC), space time trellis code (STTC), Rayleigh channel
Procedia PDF Downloads 34715167 The Moderating Effect of Intellectual Capital on the Relationship of Innovation Practices in SME’s Performance
Authors: Hussen Nasir, Mohd Fitri Mansor, Noor Hidayah Abu
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Liberation of the SME market led to a dynamic competitive business environment. SMEs are considered as an engine for economic growth of most nations. SMEs must be willing to adopt the latest technology and incorporate innovation as part of their business strategies. The aim of this study is to examine the innovation practices (innovation strategy and innovation culture) towards sustaining SME’s performance and the moderating effect of intellectual capital on the relationship of innovation practices on SME’s performance. The study will identify the strongest variables that influence the SMEs performance and proposed several hypothesis toward innovation and intellectual capital. Finally, the study will propose a theoretical framework. The current study will contribute to the knowledge of important on the element of intellectual capital as well as innovation practices in the SMEs performance.Keywords: intellectual capital, innovation practices, SMEs, performance, innovation strategy, innovation culture
Procedia PDF Downloads 46915166 An Empirical Study of Performance Management System: Implementation of Performance Management Cycle to Achieve High-Performance Culture at Pertamina Company, Indonesia
Authors: Arif Budiman
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Any organization or company that wishes to achieve vision, mission, and goals of the organization is required to implement a performance management system or known as the Performance Management System (PMS) in every part of the whole organization. PMS is a tool to help visualize the direction and work program of the organization to achieve the goal. The challenge is PMS should not stop merely as a visualization tool to achieve the vision and mission of the organization, but PMS should also be able to create a high-performance culture that is inherent in each individual of the organization. Establishment of a culture within an organization requires the support of top leaders and also requires a system or governance that encourages every individual in the organization to be involved in any work program of the organization. Keywords of creating a high-performance culture are the formation of communication pattern involving the whole individual, either vertically or horizontally, and performed consistently and persistently by all individuals in each line of the organization. PT Pertamina (Persero) as the state-owned national energy company holds a system to internalize the culture of high performance through a system called Performance Management System Cycle (PMS Cycle). This system has 7 stages of the cycle, those are: (1) defining vision, mission and strategic plan of the company, (2) defining key performance indicator of each line and the individual (‘expectation setting conversation’), (3) defining performance target and performance agreement, (4) monitoring performance on a monthly regular basis (‘pulse check’), (5) implementing performance dialogue between leaders and staffs periodically every 3 months (‘performance dialogue’), (6) defining rewards and consequences based on the achievement of the performance of each line and the individual, and (7) calculating the final performance value achieved by each line and individual from one period of the current year. Perform PMS is a continual communication running throughout the year, that is why any three performance discussion that should be performed, include expectation setting conversations, pulse check and performance dialogue. In addition, another significant point and necessary undertaken to complete the assessment of individual performance assessment is soft competencies through 360-degree assessment by leaders, staffs, and peers.Keywords: 360-degree assessment, expectation setting conversation, performance management system cycle, performance dialogue, pulse check
Procedia PDF Downloads 44015165 Board of Directors Characteristics and Credit Union Financial Performance
Authors: Luisa Unda, Kamran Ahmed, Paul Mather
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We examine the effect of board characteristics on the performance and asset quality of credit unions in Australia, using a large sample covering the period 2004-2012. Credit unions are unique in that they are customer-owned financial institutions and directors are democratically elected by members, which is distinctly different from other financial institutions, such as commercial banks. We find that board remuneration, board expertise, and attendance at board meetings have significantly positive impacts on credit union performance and asset quality, while board members who hold multiple directorships (busy directors), have a significant negative impact on credit union performance. Financial performance also improves with larger boards and long-tenured directors in credit unions. All of these relations hold after we control for alternative measures of performance, credit union characteristics and endogeneity problem.Keywords: credit unions, corporate governance, board of directors, financial performance, Australia, asset quality
Procedia PDF Downloads 51615164 Recovery of Copper and Gold by Delamination of Printed Circuit Boards Followed by Leaching and Solvent Extraction Process
Authors: Kamalesh Kumar Singh
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Due to increasing trends of electronic waste, specially the ICT related gadgets, their green recycling is still a greater challenge. This article presents a two-stage, eco-friendly hydrometallurgical route for the recovery of gold from the delaminated metallic layers of waste mobile phone Printed Circuit Boards (PCBs). Initially, mobile phone PCBs are downsized (1x1 cm²) and treated with an organic solvent dimethylacetamide (DMA) for the separation of metallic fraction from non-metallic glass fiber. In the first stage, liberated metallic sheets are used for the selective dissolution of copper in an aqueous leaching reagent. Influence of various parameters such as type of leaching reagent, the concentration of the solution, temperature, time and pulp density are optimized for the effective leaching (almost 100%) of copper. Results have shown that 3M nitric acid is a suitable reagent for copper leaching at room temperature and considering chemical features, gold remained in solid residue. In the second stage, the separated residue is used for the recovery of gold by using sulphuric acid with a combination of halide salt. In this halide leaching, Cl₂ or Br₂ is generated as an in-situ oxidant to improve the leaching of gold. Results have shown that almost 92 % of gold is recovered at the optimized parameters.Keywords: printed circuit boards, delamination, leaching, solvent extraction, recovery
Procedia PDF Downloads 5415163 Number Sense Proficiency and Problem Solving Performance of Grade Seven Students
Authors: Laissa Mae Francisco, John Rolex Ingreso, Anna Krizel Menguito, Criselda Robrigado, Rej Maegan Tuazon
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This study aims to determine and describe the existing relationship between number sense proficiency and problem-solving performance of grade seven students from Victorino Mapa High School, Manila. A paper pencil exam containing of 50-item number sense test and 5-item problem-solving test which measures their number sense proficiency and problem-solving performance adapted from McIntosh, Reys, and Bana were used as the research instruments. The data obtained from this study were interpreted and analyzed using the Pearson – Product Moment Coefficient of Correlation to determine the relationship between the two variables. It was found out that students who were low in number sense proficiency tend to be the students with poor problem-solving performance and students with medium number sense proficiency are most likely to have an average problem-solving performance. Likewise, students with high number sense proficiency are those who do excellently in problem-solving performance.Keywords: number sense, performance, problem solving, proficiency
Procedia PDF Downloads 43515162 Corporate Governance and Firm Performance in the UAE
Authors: Bakr Ali Al-Gamrh, Ku Nor Izah B. Ku Ismail
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We investigate the relationship between corporate governance, leverage, risk, and firm performance. We use a firm level panel that spans the period 2008 to 2012 of all listed firms on Abu Dhabi Stock Exchange and Dubai Financial Market. After constructing an index of corporate governance strength, we find a negative effect of corporate governance on firm performance. We, however, discover that corporate governance strength indirectly improves the negative influence of leverage on firm performance in normal times. On the contrary, the results completely reversed when there is a black swan event. Corporate governance strength plays a significantly negative role in moderating the relationship between leverage and firm performance during the financial crisis. We also reveal that corporate governance strength increases firms’ risk and deteriorates performance during crisis. Results provide evidence that corporate governance indirectly plays a completely different role in different time periods.Keywords: corporate governance, firm performance, risk, leverage, the UAE
Procedia PDF Downloads 54715161 Machines Hacking Humans: Performances Practices in Electronic Music during the 21st Century
Authors: Zimasa Siyasanga Gysman
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This paper assesses the history of electronic music and its performance to illustrate that machines and technology have largely influenced how humans perform electronic music. The history of electronic music mainly focuses on the composition and production of electronic music with little to no attention paid to its performance by the majority of scholars in this field. Therefore, establishing a history of performance involves investigating what compositions of electronic music called for in the production of electronic music performance. This investigation into seminal works in the history of electronic music, therefore, illustrates the aesthetics of electronic music performance and the aesthetics established in the very beginnings of electronic music performance demonstrate the aesthetics of electronic music which are still prevalent today. The key aesthetics are the repurposing of technology and the hybridisation of technology. Performers take familiar technology (technology that society has become accustomed to using in daily life), not necessarily related to music or performance and use it as an instrument in their performances, such as a rotary dial telephone. Likewise, since the beginnings of electronic music, producers have always experimented with the latest technologies available to them in their compositions and performances. The spirit of performers of electronic music, therefore, revolves around repurposing familiar technologies and using them in new ways, whilst similarly experimenting with new technologies in their performances. This process of hybridisation plays a key role in the production and performance of electronic music in the twentieth century. Through various interviews with performers of electronic music, it is shown that these aesthetics are driving performance practices in the twenty-first century.Keywords: body, hybridisation, performance, sound
Procedia PDF Downloads 15915160 Biologically Inspired Small Infrared Target Detection Using Local Contrast Mechanisms
Authors: Tian Xia, Yuan Yan Tang
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In order to obtain higher small target detection accuracy, this paper presents an effective algorithm inspired by the local contrast mechanism. The proposed method can enhance target signal and suppress background clutter simultaneously. In the first stage, a enhanced image is obtained using the proposed Weighted Laplacian of Gaussian. In the second stage, an adaptive threshold is adopted to segment the target. Experimental results on two changeling image sequences show that the proposed method can detect the bright and dark targets simultaneously, and is not sensitive to sea-sky line of the infrared image. So it is fit for IR small infrared target detection.Keywords: small target detection, local contrast, human vision system, Laplacian of Gaussian
Procedia PDF Downloads 46615159 Sustainable Human Resource Management in the Hotel Industry: Assessing the Mediating Effect of Physiological Climate on Employee Performance
Authors: Mohammad Salameh Almasarweh
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The primary aim of this research is to explore the mediating role of physiological climate in the relationship between green HRM practices (specifically, GHRM practices, GHRM recruitment, GHRM training, GHRM performance appraisal, and GHRM empowerment) and employee performance within the hotel industry. The study revealed that green HRM practices, encompassing green recruiting, green training, green performance evaluation, and green empowerment, exerted a statistically significant influence on employee performance. A quantitative method was employed for this research, focusing on hotel managers in Jordan as the study's population. Data were collected through a questionnaire distributed to a convenience sample of 300 managers from various hotels in Jordan. The results of the study align with prior research, supporting the notion that green HRM practices positively impact both employee performance and physiological climate. Furthermore, the findings of this study indicate that physiological climate acts as a mediating factor in the relationship between green HRM practices and employee performance in Jordanian hotels.Keywords: GHRM practices, GHRM recruitment, GHRM training, GHRM performance appraisal, GHRM empowerment, employee’s performance, physiological climate
Procedia PDF Downloads 6615158 Analysis of Performance Improvement Factors in Supply Chain Manufacturing Using Analytic Network Process and Kaizen
Authors: Juliza Hidayati, Yesie M. Sinuhaji, Sawarni Hasibuan
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A company producing drinking water through many incompatibility issues that affect supply chain performance. The study was conducted to determine the factors that affect the performance of the supply chain and improve it. To obtain the dominant factors affecting the performance of the supply chain used Analytic Network Process, while to improve performance is done by using Kaizen. Factors affecting the performance of the supply chain to be a reference to identify the cause of the non-conformance. Results weighting using ANP indicates that the dominant factor affecting the level of performance is the precision of the number of shipments (15%), the ability of the fulfillment of the booking amount (12%), and the number of rejected products when signing (12%). Incompatibility of the factors that affect the performance of the supply chain are identified, so that found the root cause of the problem is most dominant. Based on the weight of Risk Priority Number (RPN) gained the most dominant root cause of the problem, namely the poorly maintained engine, the engine worked for three shifts, machine parts that are not contained in the plant. Improvements then performed using the Kaizen method of systematic and sustainable.Keywords: analytic network process, booking amount, risk priority number, supply chain performance
Procedia PDF Downloads 29315157 Measurement of Operational and Environmental Performance of the Coal-Fired Power Plants in India by Using Data Envelopment Analysis
Authors: Vijay Kumar Bajpai, Sudhir Kumar Singh
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In this study, the performance analyses of the twenty five coal-fired power plants (CFPPs) used for electricity generation are carried out through various data envelopment analysis (DEA) models. Three efficiency indices are defined and pursued. During the calculation of the operational performance, energy and non-energy variables are used as input, and net electricity produced is used as desired output. CO2 emitted to the environment is used as the undesired output in the computation of the pure environmental performance while in Model-3 CO2 emissions is considered as detrimental input in the calculation of operational and environmental performance. Empirical results show that most of the plants are operating in increasing returns to scale region and Mettur plant is efficient one with regards to energy use and environment. The result also indicates that the undesirable output effect is insignificant in the research sample. The present study will provide clues to plant operators towards raising the operational and environmental performance of CFPPs.Keywords: coal fired power plants, environmental performance, data envelopment analysis, operational performance
Procedia PDF Downloads 45315156 Value Chain Analysis of Melon “Egusi” (Citrullus lanatus Thunb. Mansf) among Rural Farm Enterprises in South East, Nigeria
Authors: Chigozirim Onwusiribe, Jude Mbanasor
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Egusi Melon (Citrullus Lanatus Thunb. Mansf ) is a very important oil seed that serves a major ingredient in the diet of most of the households in Nigeria. Egusi Melon is very nutritious and very important in meeting the food security needs of Nigerians. Egusi Melon is cultivated in most farm enterprise in South East Nigeria but the profitability of its value chain needs to be investigated. This study analyzed the profitability of the Egusi Melon value chain. Specifically this study developed a value chain map for Egusi Melon, analysed the profitability of each stage of the Egusi Melon Value chain and analysed the determinants of the profitability of the Egusi Melon at each stage of the value chain. Multi stage sampling technique was used to select 125 farm enterprises with similar capacity and characteristics. Questionnaire and interview were used to elicit the required data while descriptive statistics, Food and Agriculture Organization Value Chain Analysis Tool, profitability ratios and multiple regression analysis were used for the data analysis. One of the findings showed that the stages of the Egusi Melon value chain are very profitable. Based on the findings, we recommend the provision of grants by government and donor agencies to the farm enterprises through their cooperative societies, this will provide the necessary funds for the local fabrication of value addition and processing equipment to suit their unique value addition needs not met by the imported equipment.Keywords: value, chain, melon, farm, enterprises
Procedia PDF Downloads 13215155 A Proposal of Advanced Key Performance Indicators for Assessing Six Performances of Construction Projects
Authors: Wi Sung Yoo, Seung Woo Lee, Youn Kyoung Hur, Sung Hwan Kim
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Large-scale construction projects are continuously increasing, and the need for tools to monitor and evaluate the project success is emphasized. At the construction industry level, there are limitations in deriving performance evaluation factors that reflect the diversity of construction sites and systems that can objectively evaluate and manage performance. Additionally, there are difficulties in integrating structured and unstructured data generated at construction sites and deriving improvements. In this study, we propose the Key Performance Indicators (KPIs) to enable performance evaluation that reflects the increased diversity of construction sites and the unstructured data generated, and present a model for measuring performance by the derived indicators. The comprehensive performance of a unit construction site is assessed based on 6 areas (Time, Cost, Quality, Safety, Environment, Productivity) and 26 indicators. We collect performance indicator information from 30 construction sites that meet legal standards and have been successfully performed. And We apply data augmentation and optimization techniques into establishing measurement standards for each indicator. In other words, the KPI for construction site performance evaluation presented in this study provides standards for evaluating performance in six areas using institutional requirement data and document data. This can be expanded to establish a performance evaluation system considering the scale and type of construction project. Also, they are expected to be used as a comprehensive indicator of the construction industry and used as basic data for tracking competitiveness at the national level and establishing policies.Keywords: key performance indicator, performance measurement, structured and unstructured data, data augmentation
Procedia PDF Downloads 4015154 Performance Complexity Measurement of Tightening Equipment Based on Kolmogorov Entropy
Authors: Guoliang Fan, Aiping Li, Xuemei Liu, Liyun Xu
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The performance of the tightening equipment will decline with the working process in manufacturing system. The main manifestations are the randomness and discretization degree increasing of the tightening performance. To evaluate the degradation tendency of the tightening performance accurately, a complexity measurement approach based on Kolmogorov entropy is presented. At first, the states of performance index are divided for calibrating the discrete degree. Then the complexity measurement model based on Kolmogorov entropy is built. The model describes the performance degradation tendency of tightening equipment quantitatively. At last, a study case is applied for verifying the efficiency and validity of the approach. The research achievement shows that the presented complexity measurement can effectively evaluate the degradation tendency of the tightening equipment. It can provide theoretical basis for preventive maintenance and life prediction of equipment.Keywords: complexity measurement, Kolmogorov entropy, manufacturing system, performance evaluation, tightening equipment
Procedia PDF Downloads 25915153 Size-Reduction Strategies for Iris Codes
Authors: Jutta Hämmerle-Uhl, Georg Penn, Gerhard Pötzelsberger, Andreas Uhl
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Iris codes contain bits with different entropy. This work investigates different strategies to reduce the size of iris code templates with the aim of reducing storage requirements and computational demand in the matching process. Besides simple sub-sampling schemes, also a binary multi-resolution representation as used in the JBIG hierarchical coding mode is assessed. We find that iris code template size can be reduced significantly while maintaining recognition accuracy. Besides, we propose a two stage identification approach, using small-sized iris code templates in a pre-selection satge, and full resolution templates for final identification, which shows promising recognition behaviour.Keywords: iris recognition, compact iris code, fast matching, best bits, pre-selection identification, two-stage identification
Procedia PDF Downloads 43715152 Crack Opening Investigation in Fiberconcrete
Authors: Arturs Macanovskis, Vitalijs Lusis, Andrejs Krasnikovs
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Work has three stages. In the first stage was examined pull-out process for steel fiber was embedded into a concrete by one end and was pulled out of concrete under the angle to pulling out force direction. Angle was varied. Length of steel fiber was 26 mm, diameter 0.5 mm. On the obtained force- displacement diagrams were observed jumps. For such mechanical behavior explanation, fiber channel in concrete surface microscopical experimental investigation, using microscope KEYENCE VHX2000, was performed. Surface of fiber channel in concrete matrix after pull-out test (fiber angle to pulling out force direction 70°). At the second stage were obtained diagrams for load- crack opening displacement for breaking homogeneously reinforced and layered fiber concrete prisms (with dimensions 10x10x40 cm) subjected to 4-point bending. After testing was analyzed main crack. On the main crack’s both surfaces were recognized all pulled out fibers their locations, angles to crack surface and lengths of pull-out fibers parts. At the third stage elaborated prediction model for the fiber-concrete beam, failure under bending, using the following data: a) diagrams for fibers pulling out at different angles; b) experimental data about steel-straight fibers locations in the main crack.Keywords: fiberconcrete, pull-out, fiber channel, layered fiberconcrete
Procedia PDF Downloads 43815151 An Exploratory Study of Effects of Parenting Styles on Maternal Expectation and Perception of Compliance among Adolescents
Authors: Anton James
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This study explored the contribution of parenting styles in the Maternal Perception of Compliance Model (MPCM). This model explores maternal expectations to illustrate the formation of maternal perception of severity of noncompliance in adolescent children. The methodology consisted of three stages: In the first stage, a focus group was held, and the data was analysed to fine-tune the interview schedule. In the second stage, a single interview was held, and the interview schedule was further modified. The third and the final stage consisted of interviewing six mothers who had adolescent children. They were chosen with ‘maximum variation’ approach to represent three tiered socioeconomic statuses, and Asian, white and black ethnicities. The data was thematically analysed in a hybrid fashion: inductive coding and deductive assignment of codes into discrete parenting styles. The study found: a) parenting styles are not always discrete and sometimes it can be mixed. b) The parenting styles are influenced by culture, socioeconomic status, transgenerational knowledge, academic knowledge, observational knowledge, self-reflective knowledge, and parental anxiety. c) The parenting style functioned a mediating mechanism where it attempted to converge discrepancies between parental expectations of compliance with maternal perception of severity of noncompliance. The findings of parenting styles were discussed in relation to MPCM.Keywords: compliance, expectation, parenting styles, perception
Procedia PDF Downloads 77915150 A Tool for Assessing Performance and Structural Quality of Business Process
Authors: Mariem Kchaou, Wiem Khlif, Faiez Gargouri
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Modeling business processes is an essential task when evaluating, improving, or documenting existing business processes. To be efficient in such tasks, a business process model (BPM) must have high structural quality and high performance. Evidently, evaluating the performance of a business process model is a necessary step to reduce time, cost, while assessing the structural quality aims to improve the understandability and the modifiability of the BPMN model. To achieve these objectives, a set of structural and performance measures have been proposed. Since the diversity of measures, we propose a framework that integrates both structural and performance aspects for classifying them. Our measure classification is based on business process model perspectives (e.g., informational, functional, organizational, behavioral, and temporal), and the elements (activity, event, actor, etc.) involved in computing the measures. Then, we implement this framework in a tool assisting the structural quality and the performance of a business process. The tool helps the designers to select an appropriate subset of measures associated with the corresponding perspective and to calculate and interpret their values in order to improve the structural quality and the performance of the model.Keywords: performance, structural quality, perspectives, tool, classification framework, measures
Procedia PDF Downloads 15215149 Banking Performance and Political Economy: Using ARDL Model
Authors: Marwen Ghouil, Jamel Eddine Mkadmi
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Banking performance is the pillar and goal of all banking activity and its impact on economic policy. First, researchers defined the principles for assessing and modeling bank performance, and then theories and models explaining bank performance were developed. The importance of credit as a means of financing businesses in most developing countries has led to questions about the effects of financial liberalisation on increased banking competition. In Tunisia, as in many other countries, the liberalization of financial services in general and of banks' activities has not ceased to evolve. The objective of this paper is to examine the determinants of banking performance for 8 Tunisian banks and their impact on economic policy during the Arab Spring. We used cointegration analysis and the ARDL Panel model, explaining using total assets, bank credits, guarantees, and bank size as performance drivers. The correlation analysis shows that there is a positive correlation relationship between total assets, bank credits, guarantees, and bank size and bank performance. Long-term empirical results show that bank loans, guarantees, bank size, and total assets have a positive and significant impact on bank performance. This means that bank credits, guarantees, bank size, and total assets are very important determinants of bank performance in Tunisia.Keywords: bank performance, economic policy, finance, economic
Procedia PDF Downloads 13215148 Model Organic Ranikin Cycle Power Plant for Waste Heat Recovery in Olkaria-I Geothermal Power Plant
Authors: Haile Araya Nigusse, Hiram M. Ndiritu, Robert Kiplimo
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Energy consumption is an indispensable component for the continued development of the human population. The global energy demand increases with development and population rise. The increase in energy demand, high cost of fossil fuels and the link between energy utilization and environmental impacts have resulted in the need for a sustainable approach to the utilization of the low grade energy resources. The Organic Rankine Cycle (ORC) power plant is an advantageous technology that can be applied in generation of power from low temperature brine of geothermal reservoirs. The power plant utilizes a low boiling organic working fluid such as a refrigerant or a hydrocarbon. Researches indicated that the performance of ORC power plant is highly dependent upon factors such as proper organic working fluid selection, types of heat exchangers (condenser and evaporator) and turbine used. Despite a high pressure drop, shell-tube heat exchangers have satisfactory performance for ORC power plants. This study involved the design, fabrication and performance assessment of the components of a model Organic Rankine Cycle power plant to utilize the low grade geothermal brine. Two shell and tube heat exchangers (evaporator and condenser) and a single stage impulse turbine have been designed, fabricated and the performance assessment of each component has been conducted. Pentane was used as a working fluid and hot water simulating the geothermal brine. The results of the experiment indicated that the increase in mass flow rate of hot water by 0.08 kg/s caused a rise in overall heat transfer coefficient of the evaporator by 17.33% and the heat transferred was increased by 6.74%. In the condenser, the increase of cooling water flow rate from 0.15 kg/s to 0.35 kg/s increased the overall heat transfer coefficient by 1.21% and heat transferred was increased by 4.26%. The shaft speed varied from 1585 to 4590 rpm as inlet pressure was varied from 0.5 to 5.0 bar and power generated was varying from 4.34 to 14.46W. The results of the experiments indicated that the performance of each component of the model Organic Rankine Cycle power plant operating at low temperature heat resources was satisfactory.Keywords: brine, heat exchanger, ORC, turbine
Procedia PDF Downloads 64815147 Experimental Investigation and Numerical Simulations of the Cylindrical Machining of a Ti-6Al-4V Tree
Authors: Mohamed Sahli, David Bassir, Thierry Barriere, Xavier Roizard
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Predicting the behaviour of the Ti-6Al-4V alloy during the turning operation was very important in the choice of suitable cutting tools and also in the machining strategies. In this study, a 3D model with thermo-mechanical coupling has been proposed to study the influence of cutting parameters and also lubrication on the performance of cutting tools. The constants of the constitutive Johnson-Cook model of Ti-6Al-4V alloy were identified using inverse analysis based on the parameters of the orthogonal cutting process. Then, numerical simulations of the finishing machining operation were developed and experimentally validated for the cylindrical stock removal stage with the finishing cutting tool.Keywords: titanium turning, cutting tools, FE simulation, chip
Procedia PDF Downloads 17215146 Development and Effects of Transtheoretical Model Exercise Program for Elderly Women with Chronic Back Pain
Authors: Hyun-Ju Oh, Soon-Rim Suh, Mihan Kim
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The steady and rapid increase of the older population is a global phenomenon. Chronic diseases and disabilities are increased due to aging. In general, exercise has been known to be most effective in preventing and managing chronic back pain. However, it is hard for the older women to initiate and maintain the exercise. Transtheoretical model (TTM) is one of the theories explain behavioral changes such as exercise. The application of the program considering the stage of behavior change is effective for the elderly woman to start and maintain the exercise. The purpose of this study was to develop TTM based exercise program and to examine its effect for elderly women with chronic back-pain. For the program evaluation, the non-equivalent control pre-posttest design was applied. The independent variable of this study is exercise intervention program. The contents of the program were constructed considering the characteristics of the elderly women with chronic low back pain, focusing on the process of change, the stage of change by the previous studies. The developed exercise program was applied to the elderly women with chronic low back pain in the planning stage and the preparation stage. The subjects were 50 older women over 65 years of age with chronic back-pain who did not practice regular exercise. The experimental group (n=25) received the 8weeks TTM based exercise program. The control group received the book which named low back pain management. Data were collected at three times: before the exercise intervention, right after the intervention, and 4weeks after the intervention. The dependent variables were the processes of change, decisional balance, exercise self-efficacy, back-pain, depression and muscle strength. The results of this study were as follows. Processes of change (<.001), pros of decisional balance (<.001), exercise self-efficacy (<.001), back pain (<.001), depression (<.001), muscle strength (<.001) were higher in the experimental group than in the control group right after the program and 4weeks after the programs. The results of this study show that applying the TTM based exercise program increases the use of the change process, increases the exercise self-efficacy, increases the stage of changing the exercise behavior and strengthens the muscular strength by lowering the degree of pain and depression Respectively. The significance of the study was to confirm the effect of continuous exercise by maintaining regular exercise habits by applying exercise program of the transtheoretical model to the chronic low back pain elderly with exercise intention.Keywords: chronic back pain, elderly, exercise, women
Procedia PDF Downloads 25115145 Research on Fuzzy Test Framework Based on Concolic Execution
Authors: Xiong Xie, Yuhang Chen
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Vulnerability discovery technology is a significant field of the current. In this paper, a fuzzy framework based on concolic execution has been proposed. Fuzzy test and symbolic execution are widely used in the field of vulnerability discovery technology. But each of them has its own advantages and disadvantages. During the path generation stage, path traversal algorithm based on generation is used to get more accurate path. During the constraint solving stage, dynamic concolic execution is used to avoid the path explosion. If there is external call, the concolic based on function summary is used. Experiments show that the framework can effectively improve the ability of triggering vulnerabilities and code coverage.Keywords: concolic execution, constraint solving, fuzzy test, vulnerability discovery
Procedia PDF Downloads 22815144 The Impact of Change Management on Employee Satisfaction and Engagement
Authors: Ju-Chun Chien
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The main purpose of this study was to figure out employees’ attitudes toward the new performance appraisal program and to examine whether three different types of appraisal processes differentially affected job satisfaction and employee engagement. The second purpose of this study was to investigate the relationship between performance appraisal reform, job satisfaction, and employee engagement. A large polyester and textile corporation had 2046 non-operational employees in February 2014. The valid participants were 1474 (72.04%) in this study. Data analysis included descriptive statistics, one-way ANOVA, one-way MANOVA, Pearson correlation, Content Validity Index, the exploratory factor analysis, and reliability analysis. The general results showed that employees who received the new performance appraisal program viewed the program more positively and showed more job satisfaction than those who did not. In particular, the implementation effects of this new performance appraisal program were most highly rated by employees who used the KPI to evaluate their job performance. Moreover, employees’ attitudes toward the new performance appraisal program were positively related to their job satisfaction and work engagement. On the other hand, most employees regarded themselves as engaged workers. To sum up, the HR department of this company has made an effective contribution to performance appraisal reforms.Keywords: change management, employee engagement, job satisfaction, performance appraisal reform
Procedia PDF Downloads 33015143 RoboWeedSupport-Semi-Automated Unmanned Aerial System for Cost Efficient High Resolution in Sub-Millimeter Scale Acquisition of Weed Images
Authors: Simon L. Madsen, Mads Dyrmann, Morten S. Laursen, Rasmus N. Jørgensen
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Recent advances in the Unmanned Aerial System (UAS) safety and perception systems enable safe low altitude autonomous terrain following flights recently demonstrated by the consumer DJI Mavic PRO and Phamtom 4 Pro drones. This paper presents the first prototype system utilizing this functionality in form of semi-automated UAS based collection of crop/weed images where the embedded perception system ensures a significantly safer and faster gathering of weed images with sub-millimeter resolution. The system is to be used when the weeds are at cotyledon stage and prior to the harvest recognizing the grass weed species, which cannot be discriminated at the cotyledon stage.Keywords: weed mapping, UAV, DJI SDK, automation, cotyledon plants
Procedia PDF Downloads 30715142 Sequential Padding: A Method to Improve the Impact Resistance in Body Armor Materials
Authors: Ankita Srivastava, Bhupendra S. Butola, Abhijit Majumdar
Abstract:
Application of shear thickening fluid (STF) has been proved to increase the impact resistance performance of the textile structures to further use it as a body armor material. In the present research, STF was applied on Kevlar woven fabric to make the structure lightweight and flexible while improving its impact resistance performance. It was observed that getting a fair amount of add-on of STF on Kevlar fabric is difficult as Kevlar fabric comes with a pre-coating of PTFE which hinders its absorbency. Hence, a method termed as sequential padding is developed in the present study to improve the add-on of STF on Kevlar fabric. Contrary to the conventional process, where Kevlar fabric is treated with STF once using any one pressure, in sequential padding method, the Kevlar fabrics were treated twice in a sequential manner using combination of two pressures together in a sample. 200 GSM Kevlar fabrics were used in the present study. STF was prepared by adding PEG with 70% (w/w) nano-silica concentration. Ethanol was added with the STF at a fixed ratio to reduce viscosity. A high-speed homogenizer was used to make the dispersion. Total nine STF treated Kevlar fabric samples were prepared by using varying combinations and sequences of three levels of padding pressure {0.5, 1.0 and 2.0 bar). The fabrics were dried at 80°C for 40 minutes in a hot air oven to evaporate ethanol. Untreated and STF treated fabrics were tested for add-on%. Impact resistance performance of samples was also tested on dynamic impact tester at a fixed velocity of 6 m/s. Further, to observe the impact resistance performance in actual condition, low velocity ballistic test with 165 m/s velocity was also performed to confirm the results of impact resistance test. It was observed that both add-on% and impact energy absorption of Kevlar fabrics increases significantly with sequential padding process as compared to untreated as well as single stage padding process. It was also determined that impact energy absorption is significantly better in STF treated Kevlar fabrics when 1st padding pressure is higher, and 2nd padding pressure is lower. It is also observed that impact energy absorption of sequentially padded Kevlar fabric shows almost 125% increase in ballistic impact energy absorption (40.62 J) as compared to untreated fabric (18.07 J).The results are owing to the fact that the treatment of fabrics at high pressure during the first padding is responsible for uniform distribution of STF within the fabric structures. While padding with second lower pressure ensures the high add-on of STF for over-all improvement in the impact resistance performance of the fabric. Therefore, it is concluded that sequential padding process may help to improve the impact performance of body armor materials based on STF treated Kevlar fabrics.Keywords: body armor, impact resistance, Kevlar, shear thickening fluid
Procedia PDF Downloads 23815141 Compact, Lightweight, Low Cost, Rectangular Core Power Transformers
Authors: Abidin Tortum, Kubra Kocabey
Abstract:
One of the sectors where the competition is experienced at the highest level in the world is the transformer sector, and sales can be made with a limited profit margin. For this reason, manufacturers must develop cost-cutting designs to achieve higher profits. The use of rectangular cores and coils in transformer design is one of the methods that can be used to reduce costs. According to the best knowledge we have obtained, we think that we are the first company producing rectangular core power transformers in our country. BETA, to reduce the cost of this project, more compact products to reveal, as we know it to increase the alleviate and competitiveness of the product, will perform cored coil design and production rectangle for the first-time power transformers in Turkey. The transformer to be designed shall be 16 MVA, 33/11 kV voltage level. With the rectangular design of the transformer core and windings, no-load losses can be reduced. Also, the least costly transformer type is rectangular. However, short-circuit forces on rectangular windings do not affect every point of the windings in the same way. Whereas more force is applied inwards to the mid-points of the low-voltage winding, the opposite occurs in the high-voltage winding. Therefore, the windings tend to deteriorate in the event of a short circuit. While trying to reach the project objectives, the difficulties in the design should be overcome. Rectangular core transformers to be produced in our country offer a more compact structure than conventional transformers. In other words, both height and width were smaller. Thus, the reducer takes up less space in the center. Because the transformer boiler is smaller, less oil is used, and its weight is lower. Biotemp natural ester fluid is used in rectangular transformer and the cooling performance of this oil is analyzed. The cost was also reduced with the reduction of dimensions. The decrease in the amount of oil used has also increased the environmental friendliness of the developed product. Transportation costs have been reduced by reducing the total weight. The amount of carbon emissions generated during the transportation process is reduced. Since the low-voltage winding is wound with a foil winding technique, a more resistant structure is obtained against short circuit forces. No-load losses were lower due to the use of a rectangular core. The project was handled in three phases. In the first stage, preliminary research and designs were carried out. In the second stage, the prototype manufacturing of the transformer whose designs have been completed has been started. The prototype developed in the last stage has been subjected to routine, type and special tests.Keywords: rectangular core, power transformer, transformer, productivity
Procedia PDF Downloads 11915140 Algorithm and Software Based on Multilayer Perceptron Neural Networks for Estimating Channel Use in the Spectral Decision Stage in Cognitive Radio Networks
Authors: Danilo López, Johana Hernández, Edwin Rivas
Abstract:
The use of the Multilayer Perceptron Neural Networks (MLPNN) technique is presented to estimate the future state of use of a licensed channel by primary users (PUs); this will be useful at the spectral decision stage in cognitive radio networks (CRN) to determine approximately in which time instants of future may secondary users (SUs) opportunistically use the spectral bandwidth to send data through the primary wireless network. To validate the results, sequences of occupancy data of channel were generated by simulation. The results show that the prediction percentage is greater than 60% in some of the tests carried out.Keywords: cognitive radio, neural network, prediction, primary user
Procedia PDF Downloads 371