Search results for: Artificial Immune System (AIS)
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 9026

Search results for: Artificial Immune System (AIS)

7976 The Validity Range of LSDP Robust Controller by Exploiting the Gap Metric Theory

Authors: Ali Ameur Haj Salah, Tarek Garna, Hassani Messaoud

Abstract:

This paper attempts to define the validity domain of LSDP (Loop Shaping Design Procedure) controller system, by determining the suitable uncertainty region, so that linear system be stable. Indeed the LSDP controller cannot provide stability for any perturbed system. For this, we will use the gap metric tool that is introduced into the control literature for studying robustness properties of feedback systems with uncertainty. A 2nd order electric linear system example is given to define the validity domain of LSDP controller and effectiveness gap metric.

Keywords: LSDP, Gap metric, Robust Control.

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7975 An Archetype to Sustain Knowledge Management Systems through Intranet

Authors: B. T. Sayed, Nafaâ Jabeur, M. Aref

Abstract:

Creation and maintenance of knowledge management systems has been recognized as an important research area. Consecutively lack of accurate results from knowledge management systems limits the organization to apply their knowledge management processes. This leads to a failure in getting the right information to the right people at the right time thus followed by a deficiency in decision making processes. An Intranet offers a powerful tool for communication and collaboration, presenting data and information, and the means that creates and shares knowledge, all in one easily accessible place. This paper proposes an archetype describing how a knowledge management system, with the support of intranet capabilities, could very much increase the accuracy of capturing, storing and retrieving knowledge based processes thereby increasing the efficiency of the system. This system will expect a critical mass of usage, by the users, for intranet to function as knowledge management systems. This prototype would lead to a design of an application that would impose creation and maintenance of an effective knowledge management system through intranet. The aim of this paper is to introduce an effective system to handle capture, store and distribute knowledge management in a form that may not lead to any failure which exists in most of the systems. The methodology used in the system would require all the employees, in the organization, to contribute the maximum to deliver the system to a successful arena. The system is still in its initial mode and thereby the authors are under the process to practically implement the ideas, as mentioned in the system, to produce satisfactory results.

Keywords: Knowledge Management Systems, Intranet, Methodology.

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7974 Intelligent Design of Reconfigurable Machines

Authors: Majid Tolouei-Rad

Abstract:

This paper presents methodologies for developing an intelligent CAD system assisting in analysis and design of reconfigurable special machines. It describes a procedure for determining feasibility of utilizing these machines for a given part and presents a model for developing an intelligent CAD system. The system analyzes geometrical and topological information of the given part to determine possibility of the part being produced by reconfigurable special machines from a technical point of view. Also feasibility of the process from a economical point of view is analyzed. Then the system determines proper positioning of the part considering details of machining features and operations needed. This involves determination of operation types, cutting tools and the number of working stations needed. Upon completion of this stage the overall layout of the machine and machining equipment required are determined.

Keywords: CAD, Knowledge based system, Reconfigurable

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7973 PI Control for Second Order Delay System with Tuning Parameter Optimization

Authors: R. Farkh, K. Laabidi, M. Ksouri

Abstract:

In this paper, we consider the control of time delay system by Proportional-Integral (PI) controller. By Using the Hermite- Biehler theorem, which is applicable to quasi-polynomials, we seek a stability region of the controller for first order delay systems. The essence of this work resides in the extension of this approach to second order delay system, in the determination of its stability region and the computation of the PI optimum parameters. We have used the genetic algorithms to lead the complexity of the optimization problem.

Keywords: Genetic algorithm, Hermit-Biehler theorem, optimization, PI controller, second order delay system, stability region.

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7972 Distributed Case Based Reasoning for Intelligent Tutoring System: An Agent Based Student Modeling Paradigm

Authors: O. P. Rishi, Rekha Govil, Madhavi Sinha

Abstract:

Online learning with Intelligent Tutoring System (ITS) is becoming very popular where the system models the student-s learning behavior and presents to the student the learning material (content, questions-answers, assignments) accordingly. In today-s distributed computing environment, the tutoring system can take advantage of networking to utilize the model for a student for students from other similar groups. In the present paper we present a methodology where using Case Based Reasoning (CBR), ITS provides student modeling for online learning in a distributed environment with the help of agents. The paper describes the approach, the architecture, and the agent characteristics for such system. This concept can be deployed to develop ITS where the tutor can author and the students can learn locally whereas the ITS can model the students- learning globally in a distributed environment. The advantage of such an approach is that both the learning material (domain knowledge) and student model can be globally distributed thus enhancing the efficiency of ITS with reducing the bandwidth requirement and complexity of the system.

Keywords: CBR, ITS, student modeling, distributed system, intelligent agent.

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7971 Cognition of Driving Context for Driving Assistance

Authors: Manolo Dulva Hina, Clement Thierry, Assia Soukane, Amar Ramdane-Cherif

Abstract:

In this paper, we presented our innovative way of determining the driving context for a driving assistance system. We invoke the fusion of all parameters that describe the context of the environment, the vehicle and the driver to obtain the driving context. We created a training set that stores driving situation patterns and from which the system consults to determine the driving situation. A machine-learning algorithm predicts the driving situation. The driving situation is an input to the fission process that yields the action that must be implemented when the driver needs to be informed or assisted from the given the driving situation. The action may be directed towards the driver, the vehicle or both. This is an ongoing work whose goal is to offer an alternative driving assistance system for safe driving, green driving and comfortable driving. Here, ontologies are used for knowledge representation.

Keywords: Cognitive driving, intelligent transportation system, multimodal system, ontology, machine learning.

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7970 Electronic Health Record System: A Perspective to Improve the Value of Services Rendered to Patients in Healthcare Organization in Rwanda, Case of CHUB and Hopital De Nemba

Authors: Mugabe Nzarama Gabriel

Abstract:

In Rwanda, many healthcare organizations are still using a paper based patients’ data record system although it still present weaknesses to share health patients’ information across different services when necessary. In developed countries, the EHR has been put in place to revolutionize the paper based record system but still the EHR has some challenges related to privacy, security, or interoperability. The purpose of this research was to assess the existing patients’ data record system in healthcare sector in Rwanda, see what an EHR can improve to the system in place and assess the acceptance of EHR as system which is interoperable, very secure and interoperable and see whether stakeholders are ready to adopt the system. The case based methodology was used and TAM theoretical framework to design the questionnaire for the survey. A judgmental sample across two cases, CHUB and Hopital de Nemba, has been selected and SPSS has been used for descriptive statistics. After a qualitative analysis, the findings showed that the paper based record is useful, gives complete information about the patient, protects the privacy of patients but it is still less secure and less interoperable. The respondents shown that they are ready to use the proposed EHR System and want it secure, capable of enforcing the privacy but still they are not all ready for the interoperability. A conclusion has been formulated; recommendations and further research have been proposed.

Keywords: EHR system, healthcare service, TAM, privacy, interoperability.

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7969 HelpMeBreathe: A Web-Based System for Asthma Management

Authors: Alia Al Rayssi, Mahra Al Marar, Alyazia Alkhaili, Reem Al Dhaheri, Shayma Alkobaisi, Hoda Amer

Abstract:

We present in this paper a web-based system called “HelpMeBreathe” for managing asthma. The proposed system provides analytical tools, which allow better understanding of environmental triggers of asthma, hence better support of data-driven decision making. The developed system provides warning messages to a specific asthma patient if the weather in his/her area might cause any difficulty in breathing or could trigger an asthma attack. HelpMeBreathe collects, stores, and analyzes individuals’ moving trajectories and health conditions as well as environmental data. It then processes and displays the patients’ data through an analytical tool that leads to an effective decision making by physicians and other decision makers.

Keywords: Asthma, environmental triggers, map interface, peak flow, web-based system.

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7968 Hopf Bifurcation for a New Chaotic System

Authors: Kejun Zhuang

Abstract:

In this paper, a three dimensional autonomous chaotic system is considered. The existence of Hopf bifurcation is investigated by choosing the appropriate bifurcation parameter. Furthermore, formulas for determining the direction of the Hopf bifurcation and the stability of bifurcating periodic solutions are derived with the help of normal form theory. Finally, a numerical example is given.

Keywords: Chaotic system, Hopf bifurcation, normal form theory.

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7967 An Investigation of the Determinants of Knowledge Management Systems Success in Banking Industry

Authors: Nantapanuwat Nattapol, Ractham Peter, Kaewkittipong Laddawan

Abstract:

The efficient knowledge management system (KMS) is one of the important strategies to help firms to achieve sustainable competitive advantages, but little research has been conducted to understand what contributes to the KMS success. This study thus set to investigate the determinants of KMS success in the context of Thai banking industry. A questionnaire survey was conducted in four major Thai Banks to test the proposed KMS Success model. The result of this study shows that KMS use and user satisfaction relate significantly to the success of KMS, and knowledge quality, service quality and trust lead to system use, and knowledge quality, system quality and trust lead to user satisfaction. However, this research focuses only on system and user-related factors. Future research thus can extend to study factors such as management support and organization readiness.

Keywords: Knowledge, Knowledge Management, Knowledge Management system, Knowledge Management System Success, Banking Industry, Thailand

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7966 The Influence of Congruence between Incentive System and Locus of Control on Team Performance: An Experiment

Authors: Siti Mutmainah, Slamet Sugiri

Abstract:

Organizations are increasingly relying upon teamwork; however, little is known about the best fit among incentive system, team composition, and group performance. To further explore this issue this study examines whether the congruence between incentive system and locus of control (LoC) affects team performance. To reconcile opposite lines of argument in literature regarding the best incentive system for a team, this paper uses the social identity perspective and person-environment (P-E) fit theory to understand behavior in a group process. A laboratory experiment with postgraduate students is conducted to test the hypotheses. One hundred and five accounting students were assigned to three-person work groups, where they completed an independent task under one of two types of incentive—individual and group incentive systems—after their LoC was measured. The findings confirm the hypothesis. Group incentive results in an enhanced team performance. Team performance is better when there is congruence between incentive system and LoC. Group incentive system combined with external LoC results in the best performance, while individual incentive system results in a better team performance when combined with internal LoC. The result suggests that a cooperative process enables ‘ordinary people’ to obtain extraordinary results.

Keywords: Incentive system, locus of control, person-environment fit, social identity perspective, team performance.

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7965 Motion Protection System Design for a Parallel Motion Platform

Authors: Dongsu Wu, Hongbin Gu

Abstract:

A motion protection system is designed for a parallel motion platform with subsided cabin. Due to its complex structure, parallel mechanism is easy to encounter interference problems including link length limits, joints limits and self-collision. Thus a virtual spring algorithm in operational space is developed for the motion protection system to avoid potential damages caused by interference. Simulation results show that the proposed motion protection system can effectively eliminate interference problems and ensure safety of the whole motion platform.

Keywords: Motion protection, motion platform, parallelmechanism, Stewart platform, collision avoidance.

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7964 The Robot Hand System that can Control Grasping Power by SEMG

Authors: Tsubasa Seto, Kentaro Nagata, Kazushige Magatani

Abstract:

SEMG (Surface Electromyogram) is one of the bio-signals and is generated from the muscle. And there are many research results that use forearm EMG to detect hand motions. In this paper, we will talk about our developed the robot hand system that can control grasping power by SEMG. In our system, we suppose that muscle power is proportional to the amplitude of SEMG. The power is estimated and the grip power of a robot hand is able to be controlled using estimated muscle power in our system. In addition, to perform a more precise control can be considered to build a closed loop feedback system as an object to a subject to pressure from the edge of hand. Our objectives of this study are the development of a method that makes perfect detection of the hand grip force possible using SEMG patterns, and applying this method to the man-machine interface.

Keywords: SEMG, multi electrode, robot hand, power control

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7963 Assessing the Seismic Performance of Threaded Rebar Coupler System

Authors: Do-Kyu, Hwang, Ho-Young Kim, Ho-Hyeoung Choi, Gi-Beom Park, Jae-Hoon Lee

Abstract:

Currently there are many use of threaded reinforcing bars in construction fields because those do not need additional screw processing when connecting reinforcing bar by threaded coupler. In this study, reinforced concrete bridge piers using threaded rebar coupler system at the plastic hinge area were tested to evaluate seismic performance. The test results showed that threads of the threaded rebar coupler system could be loosened while under tension-compression cyclic loading because tolerance and rib face angle of a threaded rebar coupler system are greater than that of a conventional ribbed rebar coupler system. As a result, cracks were concentrated just outside of the mechanical coupler and stiffness of reinforced concrete bridge pier decreased. Therefore, it is recommended that connection ratio of mechanical couplers in one section shall be below 50% in order that cracks are not concentrated just outside of the mechanical coupler. Also, reduced stiffness of the specimen should be considered when using the threaded rebar coupler system.

Keywords: Reinforced concrete column, seismic performance, threaded rebar coupler, threaded reinforcing bar.

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7962 Object Allocation with Replication in Distributed Systems

Authors: H. T. Barney, G. C. Low

Abstract:

The design of distributed systems involves dividing the system into partitions (or components) and then allocating these partitions to physical nodes. There have been several techniques proposed for both the partitioning and allocation processes. These existing techniques suffer from a number of limitations including lack of support for replication. Replication is difficult to use effectively but has the potential to greatly improve the performance of a distributed system. This paper presents a new technique technique for allocating objects in order to improve performance in a distributed system that supports replication. The performance of the proposed technique is demonstrated and tested on an example system. The performance of the new technique is compared with the performance of an existing technique in order to demonstrate both the validity and superiority of the new technique when developing a distributed system that can utilise object replication.

Keywords: Allocation, Distributed Systems, Replication.

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7961 Performance of Laboratory Experiments over the Internet: Towards an Intelligent Tutoring System on Automatic Control

Authors: Kleanthis Prekas, Maria Rangoussi, Savvas Vassiliadis, George Prekas

Abstract:

Intelligent tutoring systems constitute an evolution of computer-aided educational software. We present here the modules of an intelligent tutoring system for Automatic Control, developed in our department. Through the software application developed,students can perform complete automatic control laboratory experiments, either over the departmental local area network or over the Internet. Monitoring of access to the system (local as well as international), along with student performance statistics, has yielded strongly encouraging results (as of fall 2004), despite the advanced technical content of the presented paradigm, thus showing the potential of the system developed for education and for training.

Keywords: Automatic control, tutoring system, Internet access, laboratory experiments.

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7960 Enhanced Clustering Analysis and Visualization Using Kohonen's Self-Organizing Feature Map Networks

Authors: Kasthurirangan Gopalakrishnan, Siddhartha Khaitan, Anshu Manik

Abstract:

Cluster analysis is the name given to a diverse collection of techniques that can be used to classify objects (e.g. individuals, quadrats, species etc). While Kohonen's Self-Organizing Feature Map (SOFM) or Self-Organizing Map (SOM) networks have been successfully applied as a classification tool to various problem domains, including speech recognition, image data compression, image or character recognition, robot control and medical diagnosis, its potential as a robust substitute for clustering analysis remains relatively unresearched. SOM networks combine competitive learning with dimensionality reduction by smoothing the clusters with respect to an a priori grid and provide a powerful tool for data visualization. In this paper, SOM is used for creating a toroidal mapping of two-dimensional lattice to perform cluster analysis on results of a chemical analysis of wines produced in the same region in Italy but derived from three different cultivators, referred to as the “wine recognition data" located in the University of California-Irvine database. The results are encouraging and it is believed that SOM would make an appealing and powerful decision-support system tool for clustering tasks and for data visualization.

Keywords: Artificial neural networks, cluster analysis, Kohonen maps, wine recognition.

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7959 Small Scale Solar-Photovoltaic and Wind Pump-Storage Hydroelectric System for Remote Residential Applications

Authors: Seshi Reddy Kasu, Florian Misoc

Abstract:

The use of hydroelectric pump-storage system at large scale, MW-size systems, is already widespread around the world. Designed for large scale applications, pump-storage station can be scaled-down for small, remote residential applications. Given the cost and complexity associated with installing a substation further than 100 miles from the main transmission lines, a remote, independent and self-sufficient system is by far the most feasible solution. This article is aiming at the design of wind and solar power generating system, by means of pumped-storage to replace the wind and /or solar power systems with a battery bank energy storage. Wind and solar pumped-storage power generating system can reduce the cost of power generation system, according to the user's electricity load and resource condition and also can ensure system reliability of power supply. Wind and solar pumped-storage power generation system is well suited for remote residential applications with intermittent wind and/or solar energy. This type of power systems, installed in these locations, could be a very good alternative, with economic benefits and positive social effects. The advantage of pumped storage power system, where wind power regulation is calculated, shows that a significant smoothing of the produced power is obtained, resulting in a power-on-demand system’s capability, concomitant to extra economic benefits.

Keywords: Battery bank, photo-voltaic, pump-storage, wind energy.

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7958 Propagation of a Generalized Beam in ABCD System

Authors: Halil Tanyer Eyyuboğu

Abstract:

For a generalized Hermite sinosiodal / hyperbolic Gaussian beam passing through an ABCD system with a finite aperture, the propagation properties are derived using the Collins integral. The results are obtained in the form of intensity graphs indicating that previously demonstrated rules of reciprocity are applicable, while the existence of the aperture accelerates this transformation.

Keywords: Optical communications, Hermite-Gaussian beams, ABCD system.

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7957 Improved BEENISH Protocol for Wireless Sensor Networks Based Upon Fuzzy Inference System

Authors: Rishabh Sharma, Renu Vig, Neeraj Sharma

Abstract:

The main design parameter of WSN (wireless sensor network) is the energy consumption. To compensate this parameter, hierarchical clustering is a technique that assists in extending duration of the networks life by efficiently consuming the energy. This paper focuses on dealing with the WSNs and the FIS (fuzzy interface system) which are deployed to enhance the BEENISH protocol. The node energy, mobility, pause time and density are considered for the selection of CH (cluster head). The simulation outcomes exhibited that the projected system outperforms the traditional system with regard to the energy utilization and number of packets transmitted to sink.

Keywords: Wireless sensor network, sink, sensor node, routing protocol, fuzzy rule, fuzzy inference system.

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7956 Effects of Combined Stimulation on the Autonomic Nervous System: A Pilot Study

Authors: Dae Won Lee, Ji Hyung Park, Sinae Eom, Syung Hyun Cho, Jong Soo Lee, Han Sung Kim

Abstract:

The autonomic nervous system has a regulatory structure that helps people adapt to changes in their environment by adjusting or modifying some functions in response to stress, and regulating involuntary function of human organs. The purpose of this study was to investigate the effect of combined stimulation, both far-infrared heating and chiropractic, on the autonomic nervous system activities using thermal image and heart rate variability. Six healthy subjects participated in this test. We compared the before and after autonomic nervous system activities through obtaining thermal image and photoplethysmogram signal. The thermal images showed that the combined stimulation changed subject-s body temperature more highly and widely than before. The result of heart rate variability indicated that LF/HF ratio decreased. We concluded that combined stimulation activates autonomic nervous system, and expected other possibilities of this combined stimulation.

Keywords: Far-infrared heating, Chiropractic, Autonomic nervous system, Heart rate variability

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7955 Conditions on Blind Source Separability of Linear FIR-MIMO Systems with Binary Inputs

Authors: Jiashan Tang

Abstract:

In this note, we investigate the blind source separability of linear FIR-MIMO systems. The concept of semi-reversibility of a system is presented. It is shown that for a semi-reversible system, if the input signals belong to a binary alphabet, then the source data can be blindly separated. One sufficient condition for a system to be semi-reversible is obtained. It is also shown that the proposed criteria is weaker than that in the literature which requires that the channel matrix is irreducible/invertible or reversible.

Keywords: Blind source separable, FIR-MIMO system, Binary input, Bezout equality.

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7954 Towards a Complete Automation Feature Recognition System for Sheet Metal Manufacturing

Authors: Bahaa Eltahawy, Mikko Ylihärsilä, Reino Virrankoski, Esko Petäjä

Abstract:

Sheet metal processing is automated, but the step from product models to the production machine control still requires human intervention. This may cause time consuming bottlenecks in the production process and increase the risk of human errors. In this paper we present a system, which automatically recognizes features from the CAD-model of the sheet metal product. By using these features, the system produces a complete model of the particular sheet metal product. Then the model is used as an input for the sheet metal processing machine. Currently the system is implemented, capable to recognize more than 11 of the most common sheet metal structural features, and the procedure is fully automated. This provides remarkable savings in the production time, and protects against the human errors. This paper presents the developed system architecture, applied algorithms and system software implementation and testing.

Keywords: Feature recognition, automation, sheet metal manufacturing, CAM, CAD.

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7953 Energy Efficiency and Renewable for Power System in Macedonia

Authors: Tomislav Stambolic, Anton Causevski

Abstract:

The deficit of power supply in Macedonia is almost 30% or reached up to 3000 GWh in a year. The existing thermal and hydro power plants are not enough to cover the power and energy, so the import increases every year. Therefore, in order to have more domestic energy supply, the new trends in renewable and energy efficiency should be implemented in power sector. The paper gives some perspectives for development of the power system in Macedonia, taking into account the growth of electricity demand and in the same time with implementation of renewable and energy efficiency. The development of power system is made for the period up to 2030 with the period of every 5 years.

Keywords: Energy, Power System, Renewable, Efficiency

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7952 Collaborative Car Pooling System

Authors: João Ferreira, Paulo Trigo, Porfírio Filipe

Abstract:

This paper describes the architecture for a collaborative Car Pooling System based on a credits mechanism to motivate the cooperation among users. Users can spend the accumulated credits on parking facilities. For this, we propose a business model to support the collaboration between a car pooling system and parking facilities. The Portuguese Lisbon-s Metropolitan area is used as application scenario.

Keywords: Car Pooling, Collaboration, Sustainable Mobility

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7951 Secure peerTalk Using PEERT System

Authors: Nebu Tom John, N. Dhinakaran

Abstract:

Multiparty voice over IP (MVoIP) systems allows a group of people to freely communicate each other via the internet, which have many applications such as online gaming, teleconferencing, online stock trading etc. Peertalk is a peer to peer multiparty voice over IP system (MVoIP) which is more feasible than existing approaches such as p2p overlay multicast and coupled distributed processing. Since the stream mixing and distribution are done by the peers, it is vulnerable to major security threats like nodes misbehavior, eavesdropping, Sybil attacks, Denial of Service (DoS), call tampering, Man in the Middle attacks etc. To thwart the security threats, a security framework called PEERTS (PEEred Reputed Trustworthy System for peertalk) is implemented so that efficient and secure communication can be carried out between peers.

Keywords: Key management system, peer-to-peer voice streaming, reputed trust management system, voice-over-IP.

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7950 Measuring Pressure Wave Velocity in a Hydraulic System

Authors: Lari Kela, Pekka Vähäoja

Abstract:

Pressure wave velocity in a hydraulic system was determined using piezo pressure sensors without removing fluid from the system. The measurements were carried out in a low pressure range (0.2 – 6 bar) and the results were compared with the results of other studies. This method is not as accurate as measurement with separate measurement equipment, but the fluid is in the actual machine the whole time and the effect of air is taken into consideration if air is present in the system. The amount of air is estimated by calculations and comparisons between other studies. This measurement equipment can also be installed in an existing machine and it can be programmed so that it measures in real time. Thus, it could be used e.g. to control dampers.

Keywords: Bulk modulus, pressure wave, sound velocity.

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7949 Report of Happiness in the Iranian Educational System: A Qualitative Research

Authors: Babak Shamshiri, Najme Dastouri

Abstract:

The purpose of this study is to understand the current situation of happiness in the Iranian educational system from the perspective of students, teachers and educational administrators. This research is done in qualitative paradigm. Data collection is done by in-depth interview method. Research participants were selected purposively according to sampling rules, with maximum variation and reaching the saturation point. According to most participants in this study, schools in Iran are not usually happy. This lack of happiness is associated with and related to the educational system, curriculum, teaching method, physical environment of schools and their facilities.

Keywords: Happiness, Iran, educational system, qualitative study.

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7948 Integration of Unified Power Flow Controller with Backup Energy Supply System for Enhancing Power System Stability

Authors: K. Saravanan

Abstract:

An electrical power system has some negative aspects such as flickering and deviations of voltage/power. This can be eliminated using energy storage devices that will provide a backup energy at the time of voltage/power deviations. Energy-storage devices get charging when system voltage/power is higher than reference value and discharging when system voltage/power is lower than reference value, it is acting as catalysts to provide energy boost. In this paper, a dynamic control of Unified Power Flow Controller (UPFC) integrated with superconducting magnetic energy storage (SMES) is developed to improve the power quality, power oscillation damping, and dynamic voltage stability through the transmission line. UPFC inter-connected to SMES through an interface with DC-DC chopper. This inter-connected system is capable of injecting (absorbing) the real and reactive power into (from) the system at the beginning of stability problems. In this paper, the simulation results of UPFC integrated with SMES and UPFC integrated with fuel cells (FCs) are compared using MATLAB/Simulink software package.

Keywords: UPFC, SMES, power system stability, flexible ac transmission systems, fuel cells, chopper.

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7947 Seismic Performance Evaluation of the Composite Structural System with Separated Gravity and Lateral Resistant Systems

Authors: Zi-Ang Li, Mu-Xuan Tao

Abstract:

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.

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