Search results for: Job performance
5343 A Social Cognitive Investigation in the Context of Vocational Training Performance of People with Disabilities
Authors: Majid A. AlSayari
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The study reported here investigated social cognitive theory (SCT) in the context of Vocational Rehab (VR) for people with disabilities. The prime purpose was to increase knowledge of VR phenomena and make recommendations for improving VR services. The sample consisted of 242 persons with Spinal Cord Injuries (SCI) who completed questionnaires. A further 32 participants were Trainers. Analysis of questionnaire data was carried out using factor analysis, multiple regression analysis, and thematic analysis. The analysis suggested that, in motivational terms, and consistent with research carried out in other academic contexts, self-efficacy was the best predictor of VR performance. The author concludes that that VR self-efficacy predicted VR training performance.
Keywords: Social cognitive theory, vocational rehab, self-efficacy, proxy efficacy, people with disabilities.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 7795342 Performance Study of ZigBee-Based Wireless Sensor Networks
Authors: Afif Saleh Abugharsa
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The IEEE 802.15.4 standard is designed for low-rate wireless personal area networks (LR-WPAN) with focus on enabling wireless sensor networks. It aims to give a low data rate, low power consumption, and low cost wireless networking on the device-level communication. The objective of this study is to investigate the performance of IEEE 802.15.4 based networks using simulation tool. In this project the network simulator 2 NS2 was used to several performance measures of wireless sensor networks. Three scenarios were considered, multi hop network with a single coordinator, star topology, and an ad hoc on demand distance vector AODV. Results such as packet delivery ratio, hop delay, and number of collisions are obtained from these scenarios.Keywords: ZigBee, wireless sensor networks, IEEE 802.15.4, low power, low data rate
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 8205341 Optimum Signal-to-noise Ratio Performance of Electron Multiplying Charge Coupled Devices
Authors: Wen W. Zhang, Qian Chen
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Electron multiplying charge coupled devices (EMCCDs) have revolutionized the world of low light imaging by introducing on-chip multiplication gain based on the impact ionization effect in the silicon. They combine the sub-electron readout noise with high frame rates. Signal-to-noise Ratio (SNR) is an important performance parameter for low-light-level imaging systems. This work investigates the SNR performance of an EMCCD operated in Non-inverted Mode (NIMO) and Inverted Mode (IMO). The theory of noise characteristics and operation modes is presented. The results show that the SNR of is determined by dark current and clock induced charge at high gain level. The optimum SNR performance is provided by an EMCCD operated in NIMO in short exposure and strong cooling applications. In contrast, an IMO EMCCD is preferable.
Keywords: electron multiplying charge coupled devices, noise characteristics, operation modes, signal-to-noise ratioperformance
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 21575340 Integration of Educational Data Mining Models to a Web-Based Support System for Predicting High School Student Performance
Authors: Sokkhey Phauk, Takeo Okazaki
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The challenging task in educational institutions is to maximize the high performance of students and minimize the failure rate of poor-performing students. An effective method to leverage this task is to know student learning patterns with highly influencing factors and get an early prediction of student learning outcomes at the timely stage for setting up policies for improvement. Educational data mining (EDM) is an emerging disciplinary field of data mining, statistics, and machine learning concerned with extracting useful knowledge and information for the sake of improvement and development in the education environment. The study is of this work is to propose techniques in EDM and integrate it into a web-based system for predicting poor-performing students. A comparative study of prediction models is conducted. Subsequently, high performing models are developed to get higher performance. The hybrid random forest (Hybrid RF) produces the most successful classification. For the context of intervention and improving the learning outcomes, a feature selection method MICHI, which is the combination of mutual information (MI) and chi-square (CHI) algorithms based on the ranked feature scores, is introduced to select a dominant feature set that improves the performance of prediction and uses the obtained dominant set as information for intervention. By using the proposed techniques of EDM, an academic performance prediction system (APPS) is subsequently developed for educational stockholders to get an early prediction of student learning outcomes for timely intervention. Experimental outcomes and evaluation surveys report the effectiveness and usefulness of the developed system. The system is used to help educational stakeholders and related individuals for intervening and improving student performance.
Keywords: Academic performance prediction system, prediction model, educational data mining, dominant factors, feature selection methods, student performance.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 9905339 Performance Evaluation of Distributed and Co-Located MIMO LTE Physical Layer Using Wireless Open-Access Research Platform
Authors: Ishak Suleiman, Ahmad Kamsani Samingan, Yeoh Chun Yeow, Abdul Aziz Bin Abdul Rahman
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In this paper, we evaluate the benefits of distributed 4x4 MIMO LTE downlink systems compared to that of the co-located 4x4 MIMO LTE downlink system. The performance evaluation was carried out experimentally by using Wireless Open-Access Research Platform (WARP), where the comparison between the 4x4 MIMO LTE transmission downlink system in distributed and co-located techniques was examined. The measured Error Vector Magnitude (EVM) results showed that the distributed technique achieved better system performance compared to the co-located arrangement.Keywords: Multiple-input-multiple-output, MIMO, distributed MIMO, co-located MIMO, LTE.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 18525338 A Novel Metric for Performance Evaluation of Image Fusion Algorithms
Authors: Nedeljko Cvejic, Artur Łoza, David Bull, Nishan Canagarajah
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In this paper, we present a novel objective nonreference performance assessment algorithm for image fusion. It takes into account local measurements to estimate how well the important information in the source images is represented by the fused image. The metric is based on the Universal Image Quality Index and uses the similarity between blocks of pixels in the input images and the fused image as the weighting factors for the metrics. Experimental results confirm that the values of the proposed metrics correlate well with the subjective quality of the fused images, giving a significant improvement over standard measures based on mean squared error and mutual information.
Keywords: Fusion performance measures, image fusion, non-reference quality measures, objective quality measures.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 28455337 Seismic Performance Evaluation of the Composite Structural System with Separated Gravity and Lateral Resistant Systems
Authors: Zi-Ang Li, Mu-Xuan Tao
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During the process of the industrialization of steel structure housing, a composite structural system with separated gravity and lateral resistant systems has been applied in engineering practices, which consists of composite frame with hinged beam-column joints, steel brace and RC shear wall. As an attempt in steel structural system area, seismic performance evaluation of the separated composite structure is important for further application in steel housing. This paper focuses on the seismic performance comparison of the separated composite structural system and traditional steel frame-shear wall system under the same inter-story drift ratio (IDR) provision limit. The same architectural layout of a high-rise building is designed as two different structural systems at the same IDR level, and finite element analysis using pushover method is carried out. Static pushover analysis implies that the separated structural system exhibits different lateral deformation mode and failure mechanism with traditional steel frame-shear wall system. Different indexes are adopted and discussed in seismic performance evaluation, including IDR, safe factor (SF), shear wall damage, etc. The performance under maximum considered earthquake (MCE) demand spectrum shows that the shear wall damage of two structural systems are similar; the separated composite structural system exhibits less plastic hinges; and the SF index value of the separated composite structural system is higher than the steel frame shear wall structural system.
Keywords: Finite element analysis, seismic performance evaluation, separated composite structural system, static pushover analysis.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 5775336 Anthropometric Correlates of Balance Performance in Non-Institutionalized Elderly
Authors: Okafor UAC, Ibeabuchimn, Omidina JO, Igwesi-Chidobe CN, Akinbo SRA
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Purpose: The fear of falling is a major concern among the elderly. Sixty-five percent of individuals older than 60 years of age experience loss of balance often on a daily basis. Therefore, balance assessment in the elderly deserves special attention due to its importance in functional mobility and safety. This study aimed at assessing balance performance and comparing some anthropometric parameters among a Nigerian non-institutionalized elderly population.
Methods: Sixty one elderly subjects (31 males and 30 females) participated in this study. Their ages ranged between 62 and 84 years. Ability to maintain balance was assessed using Functional Reach Test (FRT) and Sharpened Romberg Test (SRT). Anthropometric data including age, weight, height, arm length, leg length, bi-acromial breadth, foot length and trunk length were also collected. Analysis was done using Pearson’s Product Moment Correlation Coefficient and Independent T-test, while level of significance was set as p<0.05.
Results: Age-related significant relationship was observed between balance performance and bi-acromial breadth among the elderly population. Gender and visual input also had a significant influence on balance performance. Other anthropometric variables (age, weight, height, arm length, leg length, foot length and trunk length) showed no significant relationship with balance performance among this elderly sample.
Conclusion: Only specific anthropometric variables may affect balance performances among the healthy elderly. The study further highlights the need for routine assessment of both static and dynamic balance to detect and appropriately manage aging-related diseases which could affect balance in the elderly.
Keywords: Balance Performance, Anthropometry, Non-institutionalized Elderly.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 24345335 A Simulator for Robot Navigation Algorithms
Authors: Michael A. Folcik, Bijan Karimi
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A robot simulator was developed to measure and investigate the performance of a robot navigation system based on the relative position of the robot with respect to random obstacles in any two dimensional environment. The presented simulator focuses on investigating the ability of a fuzzy-neural system for object avoidance. A navigation algorithm is proposed and used to allow random navigation of a robot among obstacles when the robot faces an obstacle in the environment. The main features of this simulator can be used for evaluating the performance of any system that can provide the position of the robot with respect to obstacles in the environment. This allows a robot developer to investigate and analyze the performance of a robot without implementing the physical robot.Keywords: Applications of Fuzzy Logic and Neural Networksin Robotics, Artificial Intelligence, Embedded Systems, MobileRobots, Robot Navigation, Robotics.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 17605334 Effect of Inventory Management on Financial Performance: Evidence from Nigerian Conglomerate Companies
Authors: Adamu Danlami Ahmed
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Inventory management is the determinant of effective and efficient work for any manager. This study looked at the relationship between inventory management and financial performance. The population of the study comprises all conglomerate quoted companies in the Nigerian Stock Exchange market as at 31st December 2010. The scope of the study covered the period from 2010 to 2014. Descriptive, Pearson correlation and multiple regressions are used to analyze the data. It was found that inventory management is significantly related to the profitability of the company. This entails that an efficient management of the inventory cycle will enhance the profitability of the company. Also, lack of proper management of it will hinder the financial performance of organizations. Based on the results, it was recommended that a conglomerate company should try to see that inventories are kept to a minimum, as well as make sure the proper checks are maintained to make sure only needed inventories are in the store. As well as to keep track of the movement of goods, in order to avoid unnecessary delay of finished and work in progress (WIP) goods in the store and warehouse.
Keywords: Finished goods, work in progress, financial performance, inventory.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 46265333 Influence of Adaptation Gain and Reference Model Parameters on System Performance for Model Reference Adaptive Control
Authors: Jan Erik Stellet
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This article presents a detailed analysis and comparative performance evaluation of model reference adaptive control systems. In contrast to classical control theory, adaptive control methods allow to deal with time-variant processes. Inspired by the works [1] and [2], two methods based on the MIT rule and Lyapunov rule are applied to a linear first order system. The system is simulated and it is investigated how changes to the adaptation gain affect the system performance. Furthermore, variations in the reference model parameters, that is changing the desired closed-loop behaviour are examinded.Keywords: Adaptive control systems, Adaptation gain, MIT rule, Lyapunov rule, Model reference adaptive control.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 22345332 Evaluating Performance of an Anomaly Detection Module with Artificial Neural Network Implementation
Authors: Edward Guillén, Jhordany Rodriguez, Rafael Páez
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Anomaly detection techniques have been focused on two main components: data extraction and selection and the second one is the analysis performed over the obtained data. The goal of this paper is to analyze the influence that each of these components has over the system performance by evaluating detection over network scenarios with different setups. The independent variables are as follows: the number of system inputs, the way the inputs are codified and the complexity of the analysis techniques. For the analysis, some approaches of artificial neural networks are implemented with different number of layers. The obtained results show the influence that each of these variables has in the system performance.
Keywords: Network Intrusion Detection, Machine learning, Artificial Neural Network.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 20825331 Improving RBF Networks Classification Performance by using K-Harmonic Means
Authors: Z. Zainuddin, W. K. Lye
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In this paper, a clustering algorithm named KHarmonic means (KHM) was employed in the training of Radial Basis Function Networks (RBFNs). KHM organized the data in clusters and determined the centres of the basis function. The popular clustering algorithms, namely K-means (KM) and Fuzzy c-means (FCM), are highly dependent on the initial identification of elements that represent the cluster well. In KHM, the problem can be avoided. This leads to improvement in the classification performance when compared to other clustering algorithms. A comparison of the classification accuracy was performed between KM, FCM and KHM. The classification performance is based on the benchmark data sets: Iris Plant, Diabetes and Breast Cancer. RBFN training with the KHM algorithm shows better accuracy in classification problem.Keywords: Neural networks, Radial basis functions, Clusteringmethod, K-harmonic means.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 18525330 A Low Voltage High Performance Self Cascode Current Mirror
Authors: Jasdeep Kaur, Nupur Prakash, S. S. Rajput
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A current mirror (CM) based on self cascode MOSFETs low voltage analog and mixed mode structures has been proposed. The proposed CM has high output impedance and can operate at 0.5 V. P-Spice simulations confirm the high performance of this CM with a bandwidth of 6.0 GHz at input current of 100 μA.Keywords: Current Mirrors, Composite Cascode Structure, Current Source/Sink
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 43895329 Performance of InGaN/GaN Laser Diode Based on Quaternary Alloys Stopper and Superlattice Layers
Authors: S. M. Thahab, H. Abu Hassan, Z. Hassan
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The optical properties of InGaN/GaN laser diode based on quaternary alloys stopper and superlattice layers are numerically studied using ISE TCAD (Integrated System Engineering) simulation program. Improvements in laser optical performance have been achieved using quaternary alloy as superlattice layers in InGaN/GaN laser diodes. Lower threshold current of 18 mA and higher output power and slope efficiency of 22 mW and 1.6 W/A, respectively, at room temperature have been obtained. The laser structure with InAlGaN quaternary alloys as an electron blocking layer was found to provide better laser performance compared with the ternary AlxGa1-xN blocking layer.
Keywords: Nitride semiconductors, InAlGaN quaternary, laserdiode, superlattice.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 20545328 Restricted Pedestrian Flow Performance Measures during Egress from a Complex Facility
Authors: Luthful A. Kawsar, Noraida A. Ghani, Anton A. Kamil, Adli Mustafa
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In this paper, we use an M/G/C/C state dependent queuing model within a complex network topology to determine the different performance measures for pedestrian traffic flow. The occupants in this network topology need to go through some source corridors, from which they can choose their suitable exiting corridors. The performance measures were calculated using arrival rates that maximize the throughputs of source corridors. In order to increase the throughput of the network, the result indicates that the flow direction of pedestrian through the corridors has to be restricted and the arrival rates to the source corridor need to be controlled.Keywords: Arrival rate, Multiple arrival sources, Probability of blocking, State dependent queuing networks, Throughput.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 15785327 Testing a Flexible Manufacturing System Facility Production Capacity through Discrete Event Simulation: Automotive Case Study
Authors: Justyna Rybicka, Ashutosh Tiwari, Shane Enticott
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In the age of automation and computation aiding manufacturing, it is clear that manufacturing systems have become more complex than ever before. Although technological advances provide the capability to gain more value with fewer resources, sometimes utilisation of the manufacturing capabilities available to organisations is difficult to achieve. Flexible manufacturing systems (FMS) provide a unique capability to manufacturing organisations where there is a need for product range diversification by providing line efficiency through production flexibility. This is very valuable in trend driven production set-ups or niche volume production requirements. Although FMS provides flexible and efficient facilities, its optimal set-up is key in achieving production performance. As many variables are interlinked due to the flexibility provided by the FMS, analytical calculations are not always sufficient to predict the FMS’ performance. Simulation modelling is capable of capturing the complexity and constraints associated with FMS. This paper demonstrates how discrete event simulation (DES) can address complexity in an FMS to optimise the production line performance. A case study of an automotive FMS is presented. The DES model demonstrates different configuration options depending on prioritising objectives: utilisation and throughput. Additionally, this paper provides insight into understanding the impact of system set-up constraints on the FMS performance and demonstrates the exploration into the optimal production set-up.
Keywords: Automotive, capacity performance, discrete event simulation, flexible manufacturing system.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 29365326 Using High Performance Computing for Online Flood Monitoring and Prediction
Authors: Stepan Kuchar, Martin Golasowski, Radim Vavrik, Michal Podhoranyi, Boris Sir, Jan Martinovic
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The main goal of this article is to describe the online flood monitoring and prediction system Floreon+ primarily developed for the Moravian-Silesian region in the Czech Republic and the basic process it uses for running automatic rainfall-runoff and hydrodynamic simulations along with their calibration and uncertainty modeling. It takes a long time to execute such process sequentially, which is not acceptable in the online scenario, so the use of a high performance computing environment is proposed for all parts of the process to shorten their duration. Finally, a case study on the Ostravice River catchment is presented that shows actual durations and their gain from the parallel implementation.
Keywords: Flood prediction process, High performance computing, Online flood prediction system, Parallelization.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 23325325 Silicon Nanowire for Thermoelectric Applications: Effects of Contact Resistance
Authors: Y. Li, K. Buddharaju, N. Singh, G. Q. Lo, S. J. Lee
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Silicon nanowire (SiNW) based thermoelectric device (TED) has potential applications in areas such as chip level cooling/ energy harvesting. It is a great challenge however, to assemble an efficient device with these SiNW. The presence of parasitic in the form of interfacial electrical resistance will have a significant impact on the performance of the TED. In this work, we explore the effect of the electrical contact resistance on the performance of a TED. Numerical simulations are performed on SiNW to investigate such effects on its cooling performance. Intrinsically, SiNW individually without the unwanted parasitic effect has excellent cooling power density. However, the cooling effect is undermined with the contribution of the electrical contact resistance.
Keywords: Thermoelectric, silicon, nanowire, electrical contact resistance, parasitics.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 21105324 The Effect of Blockage Factor on Savonius Hydrokinetic Turbine Performance
Authors: Thochi Seb Rengma, Mahendra Kumar Gupta, P. M. V. Subbarao
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Hydrokinetic turbines can be used to produce power in inaccessible villages located near rivers. The hydrokinetic turbine uses the kinetic energy of the water and maybe put it directly into the natural flow of water without dams. For off-grid power production, the Savonius-type vertical axis turbine is the easiest to design and manufacture. This proposal uses three-dimensional Computational Fluid Dynamics (CFD) simulations to measure the considerable interaction and complexity of turbine blades. Savonius hydrokinetic turbine (SHKT) performance is affected by a blockage in the river, canals, and waterways. Putting a large object in a water channel causes water obstruction and raises local free stream velocity. The blockage correction factor or velocity increment measures the impact of velocity on the performance. SHKT performance is evaluated by comparing power coefficient (Cp) with tip-speed ratio (TSR) at various blockage ratios. The maximum Cp was obtained at a TSR of 1.1 with a blockage ratio of 45%, whereas TSR of 0.8 yielded the highest Cp without blockage. The greatest Cp of 0.29 was obtained with a 45% blockage ratio compared to a Cp max of 0.18 without a blockage.
Keywords: Savonius hydrokinetic turbine, blockage ratio, vertical axis turbine, power coefficient.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1805323 Effect of Austenitization Temperature on Wear Behavior of Carbidic Austempered Ductile Iron (CADI)
Authors: Ajay Likhite, Prashant Parhad, D. R. Peshwe, S. U. Pathak
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Chromium bearing Austempered Ductile Iron (ADI) has been recently in the news for its improved wear performance over the ADI. The work presented below was taken up to study the effect of different austenitisation temperatures on the microstructure and wear performance of the Carbidic Austempered Ductile Iron (CADI). In this investigation Cr bearing ductile iron was subjected to austempering treatment to obtain an ausferritic microstructure. Two different austenitisation temperatures were selected whereas, the austempering temperature and time was kept unchanged. Microstructure and wear performance of this alloy, austenitized at two different temperatures was studied.
Keywords: Austempered Ductile Iron, Carbidic Austempered Ductile Iron.Austenitization temperature.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 20685322 PI Controller for Automatic Generation Control Based on Performance Indices
Authors: Kalyan Chatterjee
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The optimal design of PI controller for Automatic Generation Control in two area is presented in this paper. The concept of Dual mode control is applied in the PI controller, such that the proportional mode is made active when the rate of change of the error is sufficiently larger than a specified limit otherwise switched to the integral mode. A digital simulation is used in conjunction with the Hooke-Jeeve’s optimization technique to determine the optimum parameters (individual gain of proportional and integral controller) of the PI controller. Integrated Square of the Error (ISE), Integrated Time multiplied by Absolute Error(ITAE) , and Integrated Absolute Error(IAE) performance indices are considered to measure the appropriateness of the designed controller. The proposed controller are tested for a two area single nonreheat thermal system considering the practical aspect of the problem such as Deadband and Generation Rate Constraint(GRC). Simulation results show that dual mode with optimized values of the gains improved the control performance than the commonly used Variable Structure .
Keywords: Load Frequency Control, Area Control Error(ACE), Dual Mode PI Controller, Performance Index
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 21225321 The Role of Social Civil Competencies in Organizational Performance
Authors: I. Martins, A. Martins
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The European Union supports social and civil competencies as being a core element to develop sustainability of organizations, people and regions. These competencies are fundamental for the well-being of the community because they include interpersonal, intrapersonal as well as their civil, active and democratic participation in organizations. The combination of these competencies reveals the organizational socio-emotional maturity and allows relevant levels of performance. It also allows the development of various capitals, namely, human, structural, relational and social, with direct influence on performance. But along this path, the emotional aspect has not been valued as a capital, given that contemporary society is based on knowledge capital and is flooded with information viewed as a capital. The present study, based on the importance of these socio-emotional capitals, aims to show that the competencies of cooperation, interpersonal understanding, empathy, kindness, ability to listen, and tolerance, to mention a few, are strategic in consolidating knowledge within organizations. This implies that the humanizing processes, both inside and outside the organizations, are revitalized. The question is how to go about doing this and its implementation; as well as, where to begin and which guidelines to take on. These are the foci that guide the present study, bearing in mind the directions of the knowledge economy.
Keywords: Social competencies, civil competencies, humanizing, performance.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 5855320 Thermodynamic Analysis of an Ejector-Absorption Refrigeration Cycle with Using NH3-H2O
Authors: Samad Jafarmadar, Amin Habibzadeh, Mohammad Mehdi Rashidi, Sayed Sina Rezaei, Abbas Aghagoli
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In this paper, the ejector-absorption refrigeration cycle is presented. This article deals with the thermodynamic simulation and the first and second law analysis of an ammonia-water. The effects of parameters such as condenser, absorber, generator, and evaporator temperatures have been investigated. The influence of the various operating parameters on the performance coefficient and exergy efficiency of this cycle has been studied. The results show that when the temperature of different parts increases, the performance coefficient and the exergy efficiency of the cycle decrease, except for evaporator and generator, that causes an increase in coefficient of performance (COP). According to the results, absorber and ejector have the highest exergy losses in the studied conditions.Keywords: Absorption refrigeration, COP, ejector, exergy efficiency.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 12775319 Measurement of Innovation Performance
Authors: M. Chobotová, Ž. Rylková
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Time full of changes which is associated with globalization, tougher competition, changes in the structures of markets and economic downturn, that all force companies to think about their competitive advantages. These changes can bring the company a competitive advantage and that can help improve competitive position in the market. Policy of the European Union is focused on the fast growing innovative companies which quickly respond to market demands and consequently increase its competitiveness. To meet those objectives companies need the right conditions and support of their state.
Keywords: Innovation, performance, measurements metrics, indices.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 30235318 Numerical Simulation of the Effects of Nanofluid on a Heat Pipe Thermal Performance
Authors: Barzin Gavtash, Khalid Hussain, Mohammad Layeghi, Saeed Sadeghi Lafmejani
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This research aims at modeling and simulating the effects of nanofluids on cylindrical heat pipes thermal performance using the ANSYS-FLUENT CFD commercial software. The heat pipe outer wall temperature distribution, thermal resistance, liquid pressure and axial velocity in presence of suspended nano-scaled solid particle (i.e. Cu, Al2O3 and TiO2) within the fluid (water) were investigated. The effect of particle concentration and size were explored and it is concluded that the thermal performance of the heat pipe is improved when using nanofluid as the system working fluid. Additionally, it was observed that the thermal resistance of the heat pipe drops as the particle concentration level increases and particle radius decreases.
Keywords: CFD, Heat Pipe, Nanofluid, Thermal resistance
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 448595317 Optimal Power Allocation for the Proposed Asymmetric Turbo Code for 3G Systems
Authors: K. Ramasamy, B. Balamuralithara, Mohammad Umar Siddiqi
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We proposed a new class of asymmetric turbo encoder for 3G systems that performs well in both “water fall" and “error floor" regions in [7]. In this paper, a modified (optimal) power allocation scheme for the different bits of new class of asymmetric turbo encoder has been investigated to enhance the performance. The simulation results and performance bound for proposed asymmetric turbo code with modified Unequal Power Allocation (UPA) scheme for the frame length, N=400, code rate, r=1/3 with Log-MAP decoder over Additive White Gaussian Noise (AWGN) channel are obtained and compared with the system with typical UPA and without UPA. The performance tests are extended over AWGN channel for different frame size to verify the possibility of implementation of the modified UPA scheme for the proposed asymmetric turbo code. From the performance results, it is observed that the proposed asymmetric turbo code with modified UPA performs better than the system without UPA and with typical UPA and it provides a coding gain of 0.4 to 0.52dB.
Keywords: Asymmetric turbo code, Generator polynomial, Interleaver, UPA, WCDMA, cdma2000.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 18925316 Performance Evaluation of Data Mining Techniques for Predicting Software Reliability
Authors: Pradeep Kumar, Abdul Wahid
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Accurate software reliability prediction not only enables developers to improve the quality of software but also provides useful information to help them for planning valuable resources. This paper examines the performance of three well-known data mining techniques (CART, TreeNet and Random Forest) for predicting software reliability. We evaluate and compare the performance of proposed models with Cascade Correlation Neural Network (CCNN) using sixteen empirical databases from the Data and Analysis Center for Software. The goal of our study is to help project managers to concentrate their testing efforts to minimize the software failures in order to improve the reliability of the software systems. Two performance measures, Normalized Root Mean Squared Error (NRMSE) and Mean Absolute Errors (MAE), illustrate that CART model is accurate than the models predicted using Random Forest, TreeNet and CCNN in all datasets used in our study. Finally, we conclude that such methods can help in reliability prediction using real-life failure datasets.
Keywords: Classification, Cascade Correlation Neural Network, Random Forest, Software reliability, TreeNet.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 18415315 Corporate Social Responsibility Reporting, State Ownership, and Corporate Performance in China: Proof from Longitudinal Data of Publicly Traded Enterprises from 2006 to 2020
Authors: Wanda Luen-Wun Siu, Xiaowen Zhang
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This paper offered the primary methodical proof on how Corporate Social Responsibility (CSR) reporting related to enterprise earnings in listed firms in China in light of most evidence focusing on cross-sectional data or data in a short span of time. Using full economic and business panel data on China’s publicly listed enterprises from 2006 to 2020 over two decades in the China Stock Market & Accounting Research database, we found initial evidence of significant direct relations between CSR reporting and firm corporate performance in both state-owned and privately-owned firms over this period, supporting the stakeholder theory. Results also revealed that state-owned enterprises performed as well as private enterprises in the current period. But private enterprises performed better than state-owned enterprises in the subsequent years. Moreover, the release of social responsibility reports had the more significant impact on the financial performance of state-owned and private enterprises in the current period than in the subsequent periods. Specifically, CSR release was not significantly associated to the financial performance of state-owned enterprises on the lag of the first, second, and third periods. But it had an impact on the lag of the first, second, and third periods among private enterprises. Such findings suggested that CSR reporting helped improve the corporate financial performance of state-owned and private enterprises in the current period, but this kind of effect was more significant among private enterprises in the lag periods.
Keywords: China’s Listed Firm, CSR reporting, financial performance, panel analysis.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 3805314 DODR : Delay On-Demand Routing
Authors: Dong Wan-li, Gu Nai-jie, Tu Kun, Bi Kun, Liu Gang
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As originally designed for wired networks, TCP (transmission control protocol) congestion control mechanism is triggered into action when packet loss is detected. This implicit assumption for packet loss mostly due to network congestion does not work well in Mobile Ad Hoc Network, where there is a comparatively high likelihood of packet loss due to channel errors and node mobility etc. Such non-congestion packet loss, when dealt with by congestion control mechanism, causes poor TCP performance in MANET. In this study, we continue to investigate the impact of the interaction between transport protocols and on-demand routing protocols on the performance and stability of 802.11 multihop networks. We evaluate the important wireless networking events caused routing change, and propose a cross layer method to delay the unnecessary routing changes, only need to add a sensitivity parameter α , which represents the on-demand routing-s reaction to link failure of MAC layer. Our proposal is applicable to the plain 802.11 networking environment, the simulation results that this method can remarkably improve the stability and performance of TCP without any modification on TCP and MAC protocol.
Keywords: Mobile ad hoc networks (MANET), on-demandrouting, performance, transmission control protocol (TCP).
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1794