Search results for: global positioning system (GPS)
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 9289

Search results for: global positioning system (GPS)

8629 Robust Power System Stabilizer Design Using Particle Swarm Optimization Technique

Authors: Sidhartha Panda, N. P. Padhy

Abstract:

Power system stabilizers (PSS) are now routinely used in the industry to damp out power system oscillations. In this paper, particle swarm optimization (PSO) technique is applied to design a robust power system stabilizer (PSS). The design problem of the proposed controller is formulated as an optimization problem and PSO is employed to search for optimal controller parameters. By minimizing the time-domain based objective function, in which the deviation in the oscillatory rotor speed of the generator is involved; stability performance of the system is improved. The non-linear simulation results are presented under wide range of operating conditions; disturbances at different locations as well as for various fault clearing sequences to show the effectiveness and robustness of the proposed controller and their ability to provide efficient damping of low frequency oscillations. Further, all the simulations results are compared with a conventionally designed power system stabilizer to show the superiority of the proposed design approach.

Keywords: Particle swarm optimization, power system stabilizer, low frequency oscillations, power system stability.

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8628 Emission Assessment of Rice Husk Combustion for Power Production

Authors: Thipwimon Chungsangunsit, Shabbir H. Gheewala, Suthum Patumsawad

Abstract:

Rice husk is one of the alternative fuels for Thailand because of its high potential and environmental benefits. Nonetheless, the environmental profile of the electricity production from rice husk must be assessed to ensure reduced environmental damage. A 10 MW pilot plant using rice husk as feedstock is the study site. The environmental impacts from rice husk power plant are evaluated by using the Life Cycle Assessment (LCA) methodology. Energy, material and carbon balances have been determined for tracing the system flow. Carbon closure has been used for describing of the net amount of CO2 released from the system in relation to the amount being recycled between the power plant and the CO2 adsorbed by rice husk. The transportation of rice husk to the power plant has significant on global warming, but not on acidification and photo-oxidant formation. The results showed that the impact potentials from rice husk power plant are lesser than the conventional plants for most of the categories considered; except the photo-oxidant formation potential from CO. The high CO from rice husk power plant may be due to low boiler efficiency and high moisture content in rice husk. The performance of the study site can be enhanced by improving the combustion efficiency.

Keywords: Environmental impact, Fossil fuels, Life Cycle Assessment (LCA), Renewable energy, Rice husk

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8627 Numerical Simulation of R410a-R23 and R404A-R508B Cascade Refrigeration System

Authors: A. D. Parekh, P. R. Tailor, Tejendra Patel

Abstract:

Capacity and efficiency of any refrigerating system diminish rapidly as the difference between the evaporating and condensing temperature is increased by a reduction in the evaporator temperature. The single stage vapour compression refrigeration system using various refrigerants are limited to an evaporator temperature of -40 0C. Below temperature of -40 0C the either cascade refrigeration system or multi stage vapour compression system is employed. Present work describes thermal design of condenser (HTS), cascade condenser and evaporator (LTS) of R404A-R508B and R410A-R23 cascade refrigeration system. Heat transfer area of condenser, cascade condenser and evaporator for both systems are compared and the effect of condenser and evaporator temperature on heat-transfer area for both systems is studied under same operating condition. The results shows that the required heat-transfer area of condenser and cascade condenser for R410A-R23 cascade system is lower than the R404A-R508B cascade system but heat transfer area of evaporator is similar for both the system. The heat transfer area of condenser and cascade condenser decreases with increase in condenser temperature (Tc), whereas the heat transfer area of cascade condenser and evaporator increases with increase in evaporator temperature (Te).

Keywords: Heat-transfer area, R410A, R404A, R508B, R23, Refrigeration system, Thermal design

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8626 Design of Power System Stabilizer Based on Sliding Mode Control Theory for Multi- Machine Power System

Authors: Hossein Shahinzadeh, Ladan Darougaran, Ebrahim Jalili Sani, Hamed Yavari, Mahdi Mozaffari Legha

Abstract:

This paper present a new method for design of power system stabilizer (PSS) based on sliding mode control (SMC) technique. The control objective is to enhance stability and improve the dynamic response of the multi-machine power system. In order to test effectiveness of the proposed scheme, simulation will be carried out to analyze the small signal stability characteristics of the system about the steady state operating condition following the change in reference mechanical torque and also parameters uncertainties. For comparison, simulation of a conventional control PSS (lead-lag compensation type) will be carried out. The main approach is focusing on the control performance which later proven to have the degree of shorter reaching time and lower spike.

Keywords: Power system stabilizer (PSS), multi-machine power system, sliding mode control

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8625 Bifurcation and Chaos of the Memristor Circuit

Authors: Wang Zhulin, Min Fuhong, Peng Guangya, Wang Yaoda, Cao Yi

Abstract:

In this paper, a magnetron memristor model based on hyperbolic sine function is presented and the correctness proved by studying the trajectory of its voltage and current phase, and then a memristor chaotic system with the memristor model is presented. The phase trajectories and the bifurcation diagrams and Lyapunov exponent spectrum of the magnetron memristor system are plotted by numerical simulation, and the chaotic evolution with changing the parameters of the system is also given. The paper includes numerical simulations and mathematical model, which confirming that the system, has a wealth of dynamic behavior.

Keywords: Memristor, chaotic circuit, dynamical behavior, chaotic system.

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8624 Condition Monitoring for Controlling the Stability of the Rotating Machinery

Authors: A. Chellil, I. Gahlouz, S. Lecheb, A. Nour, S. Chellil, H. Mechakra, H. Kebir

Abstract:

In this paper, the experimental study for the instability of a separator rotor is presented, under dynamic loading response in the harmonic analysis condition. The global measurement and analysis of vibration on the cement separator RC500 is carried, the points of measurement used are radial dots, vertical, horizontal and oblique. The measures of trends and spectral analysis for reconnaissance of the main anomalies, the main defects in the separator and manifestation, the results prove that the defects effect has a negative effect on the stability of the rotor. Experimentally the study of the rotor in transient system allowed to determine the vibratory responses due to the unbalances and various excitations.

Keywords: Rotor, experimental, defect, frequency, specter.

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8623 An Optimal Bayesian Maintenance Policy for a Partially Observable System Subject to Two Failure Modes

Authors: Akram Khaleghei Ghosheh Balagh, Viliam Makis, Leila Jafari

Abstract:

In this paper, we present a new maintenance model for a partially observable system subject to two failure modes, namely a catastrophic failure and a failure due to the system degradation. The system is subject to condition monitoring and the degradation process is described by a hidden Markov model. A cost-optimal Bayesian control policy is developed for maintaining the system. The control problem is formulated in the semi-Markov decision process framework. An effective computational algorithm is developed, illustrated by a numerical example.

Keywords: Partially observable system, hidden Markov model, competing risks, multivariate Bayesian control.

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8622 Human Tracking across Heterogeneous Systems Based On Mobile Agent Technologies

Authors: Tappei Yotsumoto, Atsushi Nomura, Kozo Tanigawa, Kenichi Takahashi, Takao Kawamura, Kazunori Sugahara

Abstract:

In a human tracking system, expanding a monitoring range of one system is complicating the management of devices and increasing its cost. Therefore, we propose a method to realize a wide-range human tracking by connecting small systems. In this paper, we examined an agent deploy method and information contents across the heterogeneous human tracking systems. By implementing the proposed method, we can construct a human tracking system across heterogeneous systems, and the system can track a target continuously between systems.

Keywords: Human tracking system, mobile agent, monitoring.

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8621 Large Deviations for Lacunary Systems

Authors: Bainian Li, Kongsheng Zhang

Abstract:

Let Xi be a Lacunary System, we established large deviations inequality for Lacunary System. Furthermore, we gained Marcinkiewicz Larger Number Law with dependent random variables sequences.

Keywords: Lacunary system, larger deviations, Locally GeneralizedGaussian, Strong law of large numbers.

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8620 An Optimized Method for Calculating the Linear and Nonlinear Response of SDOF System Subjected to an Arbitrary Base Excitation

Authors: Hossein Kabir, Mojtaba Sadeghi

Abstract:

Finding the linear and nonlinear responses of a typical single-degree-of-freedom system (SDOF) is always being regarded as a time-consuming process. This study attempts to provide modifications in the renowned Newmark method in order to make it more time efficient than it used to be and make it more accurate by modifying the system in its own non-linear state. The efficacy of the presented method is demonstrated by assigning three base excitations such as Tabas 1978, El Centro 1940, and MEXICO CITY/SCT 1985 earthquakes to a SDOF system, that is, SDOF, to compute the strength reduction factor, yield pseudo acceleration, and ductility factor.

Keywords: Single-degree-of-freedom system, linear acceleration method, nonlinear excited system, equivalent displacement method.

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8619 New Suspension Mechanism Using Camber Thrust for a Formula Car

Authors: Shinji Kajiwara

Abstract:

The basic ability of a vehicle is to “run”, “turn” and “stop”. The safeness and comfort during a drive on various road surfaces and speed depends on the performance of these basic abilities of the vehicle. Stability and maneuverability of a vehicle are vital in automotive engineering. The stability of a vehicle is the ability of the vehicle to revert back to a stable state during a drive when faced with crosswinds and irregular road conditions. Maneuverability of a vehicle is the ability of the vehicle to change direction during a drive swiftly based on the steering of the driver. The stability and maneuverability of a vehicle can also be defined as the driving stability of the vehicle. Since the fossil fueled vehicle is the main type of transportation today, the environmental factor in automotive engineering is also vital. By improving the fuel efficiency of the vehicle, the overall carbon emission will be reduced, thus reducing the effect of global warming and greenhouse gas on the Earth. Another main focus of the automotive engineering is the safety performance of the vehicle, especially with the worrying increase of vehicle collision every day. With better safety performance of a vehicle, every driver will be more confident driving every day. Next, let us focus on the “turn” ability of a vehicle. By improving this particular ability of the vehicle, the cornering limit of the vehicle can be improved, thus increasing the stability and maneuverability factor. In order to improve the cornering limit of the vehicle, a study to find the balance between the steering systems, the stability of the vehicle, higher lateral acceleration and the cornering limit detection must be conducted. The aim of this research is to study and develop a new suspension system that will boost the lateral acceleration of the vehicle and ultimately improving the cornering limit of the vehicle. This research will also study environmental factor and the stability factor of the new suspension system. The double wishbone suspension system is widely used in a four-wheel vehicle, especially for high cornering performance sports car and racing car. The double wishbone designs allow the engineer to carefully control the motion of the wheel by controlling such parameters as camber angle, caster angle, toe pattern, roll center height, scrub radius, scuff, and more. The development of the new suspension system will focus on the ability of the new suspension system to optimize the camber control and to improve the camber limit during a cornering motion. The research will be carried out using the CAE analysis tool. Using this analysis tool we will develop a JSAE Formula Machine equipped with the double wishbone system and also the new suspension system and conduct simulation and conduct studies on the performance of both suspension systems.

Keywords: Automobile, Camber Thrust, Cornering force, Suspension.

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8618 Bureau Management Technologies and Information Systems in Developing Countries

Authors: Mehmet Altınöz

Abstract:

This study focuses on bureau management technologies and information systems in developing countries. Developing countries use such systems which facilitate executive and organizational functions through the utilization of bureau management technologies and provide the executive staff with necessary information. The concepts of data and information differ from each other in developing countries, and thus the concepts of data processing and information processing are different. Symbols represent ideas, objects, figures, letters and numbers. Data processing system is an integrated system which deals with the processing of the data related to the internal and external environment of the organization in order to make decisions, create plans and develop strategies; it goes without saying that this system is composed of both human beings and machines. Information is obtained through the acquisition and the processing of data. On the other hand, data are raw communicative messages. Within this framework, data processing equals to producing plausible information out of raw data. Organizations in developing countries need to obtain information relevant to them because rapid changes in the organizational arena require rapid access to accurate information. The most significant role of the directors and managers who work in the organizational arena is to make decisions. Making a correct decision is possible only when the directors and managers are equipped with sound ideas and appropriate information. Therefore, acquisition, organization and distribution of information gain significance. Today-s organizations make use of computer-assisted “Management Information Systems" in order to obtain and distribute information. Decision Support System which is closely related to practice is an information system that facilitates the director-s task of making decisions. Decision Support System integrates human intelligence, information technology and software in order to solve the complex problems. With the support of the computer technology and software systems, Decision Support System produces information relevant to the decision to be made by the director and provides the executive staff with supportive ideas about the decision. Artificial Intelligence programs which transfer the studies and experiences of the people to the computer are called expert systems. An expert system stores expert information in a limited area and can solve problems by deriving rational consequences. Bureau management technologies and information systems in developing countries create a kind of information society and information economy which make those countries have their places in the global socio-economic structure and which enable them to play a reasonable and fruitful role; therefore it is of crucial importance to make use of information and management technologies in order to work together with innovative and enterprising individuals and it is also significant to create “scientific policies" based on information and technology in the fields of economy, politics, law and culture.

Keywords: Bureau Management, Information Systems.

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8617 A Preliminary Conceptual Scale to Discretize the Distributed Manufacturing Continuum

Authors: Ijaz Ul Haq, Fiorenzo Franceschini

Abstract:

The distributed manufacturing methodology brings a new concept of decentralized manufacturing operations close to the proximity of end users. A preliminary scale, to measure distributed capacity and evaluate positioning of firms, is developed in this research. In the first part of the paper, a literature review has been performed which highlights the explorative nature of the studies conducted to present definitions and classifications due to novelty of this topic. From literature, five dimensions of distributed manufacturing development stages have been identified: localization, manufacturing technologies, customization and personalization, digitalization and democratization of design. Based on these determinants a conceptual scale is proposed to measure the status of distributed manufacturing of a generic firm. A multiple case study is then conducted in two steps to test the conceptual scale and to identify the corresponding level of distributed potential in each case study firm.

Keywords: Conceptual scale, distributed manufacturing, firm’s distributed capacity, manufacturing continuum.

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8616 Towards a Deeper Understanding of 21st Century Global Terrorism

Authors: Francis Jegede

Abstract:

This paper examines essential issues relating to the rise and nature of violent extremism involving non-state actors and groups in the early 21st century. The global trends in terrorism and violent extremism are examined in relation to Western governments’ counter terror operations. The paper analyses the existing legal framework for fighting violent extremism and terrorism and highlights the inherent limitations of the current International Law of War in dealing with the growing challenges posed by terrorists and violent extremist groups. The paper discusses how terrorist groups use civilians, women and children as tools and weapon of war to fuel their campaign of terror and suggests ways in which the international community could deal with the challenge of fighting terrorist groups without putting civilians, women and children in harm way. The paper emphasises the need to uphold human rights values and respect for the law of war in our response to global terrorism. The paper poses the question as to whether the current legal framework for dealing with terrorist groups is sufficient without contravening the essential provisions and ethos of the International Law of War and Human Rights. While the paper explains how terrorist groups flagrantly disregard the rule of law and disrespect human rights in their campaign of terror, it also notes instances in which the current Western strategy in fighting terrorism may be viewed or considered as conflicting with human rights and international law.

Keywords: Terrorism, law of war, international law, violent extremism.

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8615 Providing Additional Advantages for STATCOM in Power Systems by Integration of Energy Storage Device

Authors: Reza Sedaghati

Abstract:

The use of Flexible AC Transmission System (FACTS) devices in a power system can potentially overcome limitations of the present mechanically controlled transmission system. Also, the advance of technology makes possible to include new energy storage devices in the electrical power system. The integration of Superconducting Magnetic Energy Storage (SMES) into Static Synchronous Compensator (STATCOM) can lead to increase their flexibility in improvement of power system dynamic behaviour by exchanging both active and reactive powers with power grids. This paper describes structure and behaviour of SMES, specifications and performance principles of the STATCOM/SMES compensator. Moreover, the benefits and effectiveness of integrated SMES with STATCOM in power systems is presented. Also, the performance of the STATCOM/SMES compensator is evaluated using an IEEE 3-bus system through the dynamic simulation by PSCAD/EMTDC software.

Keywords: STATCOM/SMES compensator, chopper, converter, energy storage system, power systems.

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8614 Characteristics Analysis of Thermal Resistance of Cryogenic Pipeline in Vacuum Environment

Authors: Wang Zijuan, Ding Wenjing, Liu Ran

Abstract:

If an unsteady heat transfer or heat impulse happens in part of the cryogenic pipeline system of large space environment simulation equipment while running in vacuum environment, it will lead to abnormal flow of the cryogenic fluid in the pipeline. When the situation gets worse, the cryogenic fluid in the pipeline will have phase change and a gas block which results in the malfunction of the cryogenic pipeline system. Referring to the structural parameter of a typical cryogenic pipeline system and the basic equation, an analytical model and a calculation model for cryogenic pipeline system can be built. The various factors which influence the thermal resistance of a cryogenic pipeline system can be analyzed and calculated by using the qualitative analysis relation deduced for thermal resistance of pipeline. The research conclusion could provide theoretical support for the design and operation of a cryogenic pipeline system

Keywords: pipeline, vacuum, vapor quality

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8613 Formal Verification of Cache System Using a Novel Cache Memory Model

Authors: Guowei Hou, Lixin Yu, Wei Zhuang, Hui Qin, Xue Yang

Abstract:

Formal verification is proposed to ensure the correctness of the design and make functional verification more efficient. As cache plays a vital role in the design of System on Chip (SoC), and cache with Memory Management Unit (MMU) and cache memory unit makes the state space too large for simulation to verify, then a formal verification is presented for such system design. In the paper, a formal model checking verification flow is suggested and a new cache memory model which is called “exhaustive search model” is proposed. Instead of using large size ram to denote the whole cache memory, exhaustive search model employs just two cache blocks. For cache system contains data cache (Dcache) and instruction cache (Icache), Dcache memory model and Icache memory model are established separately using the same mechanism. At last, the novel model is employed to the verification of a cache which is module of a custom-built SoC system that has been applied in practical, and the result shows that the cache system is verified correctly using the exhaustive search model, and it makes the verification much more manageable and flexible.

Keywords: Cache system, formal verification, novel model, System on Chip (SoC).

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8612 Terrorism as a Threat to International Peace: A Study on 9/11 Terrorism

Authors: Aftab

Abstract:

This paper is a theory-oriented study that seeks to generalize the process through which terrorism leads to the disruption of international peace. For this, it scrutinizes 9/11 terrorism based on five analytical domains of threat—security disorder, political tensions, economic adversity, socio-ideological intolerance, and the fear and cost of counterterrorism—each of which is explored in light of specific indicators. By applying qualitative correlation method, the paper finds that terrorism immediately entails five distinct kinds of negative impacts that lead to both internal disorders caused by state weakness and global disorder caused by international tensions, which in consequence, causes international peace to be disrupted. Thus, in following inductive process, the findings of this paper help to make a general inference that terrorism is a threat to international peace. 

Keywords: Domains, global disorder, internal disorder, international peace, terrorism, threat.

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8611 Facebook Spam and Spam Filter Using Artificial Neural Networks

Authors: Fahim A., Mutahira N. Naseem

Abstract:

Spam is any unwanted electronic message or material in any form posted too many people. As the world is growing as global world, social networking sites play an important role in making world global providing people from different parts of the world a platform to meet and express their views. Among different social networking sites Facebook become the leading one. With increase in usage different users start abusive use of Facebook by posting or creating ways to post spam. This paper highlights the potential spam types nowadays Facebook users’ faces. This paper also provide the reason how user become victim to spam attack. A methodology is proposed in the end discusses how to handle different types of spam.

Keywords: Artificial neural networks, Facebook spam, social networking sites, spam filter.

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8610 Forming the Differential-Algebraic Model of Radial Power Systems for Simulation of both Transient and Steady-State Conditions

Authors: Saleh A. Al-Jufout

Abstract:

This paper presents a procedure of forming the mathematical model of radial electric power systems for simulation of both transient and steady-state conditions. The research idea has been based on nodal voltages technique and on differentiation of Kirchhoff's current law (KCL) applied to each non-reference node of the radial system, the result of which the nodal voltages has been calculated by solving a system of algebraic equations. Currents of the electric power system components have been determined by solving their respective differential equations. Transforming the three-phase coordinate system into Cartesian coordinate system in the model decreased the overall number of equations by one third. The use of Cartesian coordinate system does not ignore the DC component during transient conditions, but restricts the model's implementation for symmetrical modes of operation only. An example of the input data for a four-bus radial electric power system has been calculated.

Keywords: Mathematical Modelling, Radial Power System, Steady-State, Transients

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8609 Mechanism of Alcohol Related Disruption of the Error Monitoring and Processing System

Authors: M. O. Welcome, Y. E. Razvodovsky, E. V. Pereverzeva, V. A. Pereverzev

Abstract:

The error monitoring and processing system, EMPS is the system located in the substantia nigra of the midbrain, basal ganglia and cortex of the forebrain, and plays a leading role in error detection and correction. The main components of EMPS are the dopaminergic system and anterior cingulate cortex. Although, recent studies show that alcohol disrupts the EMPS, the ways in which alcohol affects this system are poorly understood. Based on current literature data, here we suggest a hypothesis of alcohol-related glucose-dependent system of error monitoring and processing, which holds that the disruption of the EMPS is related to the competency of glucose homeostasis regulation, which in turn may determine the dopamine level as a major component of EMPS. Alcohol may indirectly disrupt the EMPS by affecting dopamine level through disorders in blood glucose homeostasis regulation.

Keywords: Alcohol related disruption, Error monitoring andprocessing system, Mechanism.

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8608 Loss Analysis by Loading Conditions of Distribution Transformers

Authors: A. Bozkurt, C. Kocatepe, R. Yumurtaci, İ. C. Tastan, G. Tulun

Abstract:

Efficient use of energy, the increase in demand of energy and also with the reduction of natural energy sources, has improved its importance in recent years. Most of the losses in the system from electricity produced until the point of consumption is mostly composed by the energy distribution system. In this study, analysis of the resulting loss in power distribution transformer and distribution power cable is realized which are most of the losses in the distribution system. Transformer losses in the real distribution system are analyzed by CYME Power Engineering Software program. These losses are disclosed for different voltage levels and different loading conditions.

Keywords: Distribution system, distribution transformer, power cable, technical losses.

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8607 Performance Analysis of Adaptive OFDM Pre and Post-FTT Beamforming System

Authors: S. Elnobi, Iman El-Zahaby, Amr M. Mahros

Abstract:

In mobile communication systems, performance and capacity are affected by multi-path fading, delay spread and Co-Channel Interference (CCI). For this reason Orthogonal Frequency Division Multiplexing (OFDM) and adaptive antenna array are used is required. The goal of the OFDM is to improve the system performance against Inter-Symbol Interference (ISI). An array of adaptive antennas has been employed to suppress CCI by spatial technique. To suppress CCI in OFDM systems two main schemes the pre-FFT and the post-FFT have been proposed. In this paper, through a system level simulation, the behavior of the pre-FFT and post-FFT beamformers for OFDM system has been investigated based on two algorithms namely, Least Mean Squares (LMS) and Recursive Least Squares (RLS). The performance of the system is also discussed in multipath fading channel system specified by 3GPP Long Term Evolution (LTE).

Keywords: OFDM, Beamforming, Adaptive Antennas Array.

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8606 A New Robust Stability Criterion for Dynamical Neural Networks with Mixed Time Delays

Authors: Guang Zhou, Shouming Zhong

Abstract:

In this paper, we investigate the problem of the existence, uniqueness and global asymptotic stability of the equilibrium point for a class of neural networks, the neutral system has mixed time delays and parameter uncertainties. Under the assumption that the activation functions are globally Lipschitz continuous, we drive a new criterion for the robust stability of a class of neural networks with time delays by utilizing the Lyapunov stability theorems and the Homomorphic mapping theorem. Numerical examples are given to illustrate the effectiveness and the advantage of the proposed main results.

Keywords: Neural networks, Delayed systems, Lyapunov function, Stability analysis.

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8605 Damping Power System Oscillations Improvement by FACTS Devices: A Comparison between SSSC and STATCOM

Authors: J. Barati, A. Saeedian, S. S. Mortazavi

Abstract:

The main objective of this paper is a comparative investigate in enhancement of damping power system oscillation via coordinated design of the power system stabilizer (PSS) and static synchronous series compensator (SSSC) and static synchronous compensator (STATCOM). The design problem of FACTS-based stabilizers is formulated as a GA based optimization problem. In this paper eigenvalue analysis method is used on small signal stability of single machine infinite bus (SMIB) system installed with SSSC and STATCOM. The generator is equipped with a PSS. The proposed stabilizers are tested on a weakly connected power system with different disturbances and loading conditions. This aim is to enhance both rotor angle and power system stability. The eigenvalue analysis and non-linear simulation results are presented to show the effects of these FACTS-based stabilizers and reveal that SSSC exhibits the best effectiveness on damping power system oscillation.

Keywords: Power system stability, PSS, SSSC, STATCOM, Coordination, Optimization, Damping Oscillations.

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8604 Condition Monitoring System of Mine Air Compressors Based on Wireless Sensor Network

Authors: Sheng Fu, Yinbo Gao, Hao Lin

Abstract:

In the current mine air compressors monitoring system, there are some difficulties in the installation and maintenance because of the wired connection. To solve the problem, this paper introduces a new air compressors monitoring system based on ZigBee in which the monitoring parameters are transmitted wirelessly. The collecting devices are designed to form a cluster network to collect vibration, temperature, and pressure of air cylinders and other parameters. All these devices are battery-powered. Besides, the monitoring software in PC is developed using MFC. Experiments show that the designed wireless sensor network works well in the site environmental condition and the system is very convenient to be installed since the wireless connection. This monitoring system will have a wide application prospect in the upgrade of the old monitoring system of the air compressors.

Keywords: Condition monitoring, wireless sensor network, air compressor, ZigBee, data collecting

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8603 1Malaysia: National Education Challenge and Nation Building

Authors: Mohd Ridhuan Tee Abdullah, Ong Hai Liaw, Wan Norhasniah Wan Husin

Abstract:

The main issue discussed is on the role of education system in the process of nation building as a means in uniting different community ethnics which later on, hoped to shape the future ethnic relation of this country. It is generally known that political socialization experienced by each ethnic community has given birth to a vernacular education system, separated along the ethnic line. Every community shapes their own education system based on their respective mother tongue language, however all are based on the same curriculum. As a result the role of education as a uniting force is not significantly effective. Historically, it has been shown that government efforts to unite the country education system under the wing of national education system (national school) is not that successful since every community (Chinese) will defend the existence of their community education system because they want to spur their mother tongue language. The clash between national education system and vernacular education system is the root cause of stalemate in the ethnic relation in Malaysia and it always becomes a flash point when the issue is raised. The question now is what is the best solution to enhance the national education system in multiethnic Malaysia?

Keywords: Political socialization, education, national unity, national school, vernacular school and 1Malaysia

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8602 Functionality of Negotiation Agent on Value-based Design Decision

Authors: Arazi Idrus, Christiono Utomo

Abstract:

This paper presents functionality of negotiation agent on value-based design decision. The functionality is based on the characteristics of the system and goal specification. A Prometheus Design Tool model was used for developing the system. Group functionality will be the attribute for negotiation agents, which comprises a coordinator agent and decision- maker agent. The results of the testing of the system to a building system selection on valuebased decision environment are also presented.

Keywords: Functionality, negotiation agent, value-baseddecision

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8601 Fuzzy Logic Control of a Semi-Active Quarter Car System

Authors: Devdutt, M. L. Aggarwal

Abstract:

The development of vehicles having best ride comfort and safety of travelling passengers is of great interest for automotive manufacturers. The effect of transmitted vibrations from car body to passenger seat is required to be controlled for achieving the same. The application of magneto-rheological (MR) shock absorber in suspension system has been considered to achieve significant benefits in this regard. This paper introduces a secondary suspension controlled semi-active quarter car system using MR shock absorber for effective vibration control. Fuzzy logic control system is used for design of controller for actual damping force generation by MR shock absorber. Performance evaluations are done related to passenger seat acceleration and displacement in time and frequency domains, in order to see the effectiveness of the proposed semi-active suspension system. Simulation results show that the semi-active suspension system provides better results compared to passive suspension system in terms of passenger ride comfort improvement.

Keywords: Fuzzy logic control, MR shock absorber, Quarter car model, Semi-active suspension system.

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8600 Development of New Cooling System using Nacelle Duct

Authors: Minho Ha, SeungHeo, Cheolung Cheong, Park K. Y.

Abstract:

In this paper, a new cooling system using a nacelle duct is proposed for the mechanical room in the household refrigerator. The conventional mechanical room consists of a condenser, a compressor and an axial fan. The axial fan is mainly responsible for cooling the condenser and the compressor. The new cooling system is developed by replacing the axial fan with the nacelle duct including the small centrifugal fan. The parametric study is carried out to find the optimum designs of the nacelle duct in terms of performance and efficiency. Through this study, it is revealed that the new system can reduce the space, electrical power and noise compared with the conventional system

Keywords: Centrifugal Fan, Cooling Fan, Nacelle Duct, Refrigerator

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