Efficient calculation of operating security regions in power systems
July 2011
Power system operators are often faced with the challenge of identifying the dynamic operating security modes during the on-line operation of the power system, which requires fast, accurate and reliable evaluation techniques. The system security constraints are in fact boundaries that surround all possible operating modes (scenarios) of the power system. In other words, these boundaries form the feasible...
Modeling and performance analysis of uplink scheduling algorithm in mobile WiMAX systems
July 2011
Extensive numbers of the IEEE 802.16e Mobile WiMAX scheduling proposals focus on simulation for obtaining performance measures of the proposed scheduling algorithm. There is also handful of article that focused on the mathematical modeling. However, the model is derived assuming the traffic from different quality of service (QoS) classes is separated, which allow for independent analysis. In this paper, we propose an...
Modeling and controller design of an industrial hydraulic actuator system in the presence of friction and internal leakage
July 2011
This paper presents a robust controller scheme and its capabilities to control the position tracking performance of an electro-hydraulic actuator system. Sliding mode control with fixed and varying boundary layer is proposed in the scheme. It is aimed to compensate nonlinearities and uncertainties caused by the presence of friction and internal leakage. Its capabilities are verified through simulations in...
Hybrid filtering model based on particle swarm optimization and genetic algorithm
July 2011
With the rapid growth of network information, information filtering technology is more widely used. This paper discusses the content-based filtering and collaborative filtering, and proposes a hybrid filtering model with these two methods in order to overcome their own shortages. In this hybrid filtering method, genetic algorithm is used to generate initial profiles on server-side, and particle swarm...
Full-scale experiment research for performance analysis of a mechanical smoke exhaust system
July 2011
This full-scale experiment studies the efficiency of a mechanical smoke exhaust system by using hot smoke testing. The mechanical smoke exhaust system consisted of an air-conditioning system in a ceiling and its linear return diffusers were used as a smoke vent. To measure the efficiency of the system, the study included measurements of the smoke descending rate, the diffusion of heat into the room, and the...
Thermodynamic performance analysis of gas-turbine power-plant
July 2011
This paper was presented the parametric study of thermodynamic performance on gas turbine power plant. The variation of operating conditions (compression ratio, turbine inlet and exhaust temperature, air to fuel ratio, isentropic compressor and turbine efficiency, and ambient temperature) on the performance of gas turbine (thermal efficiency, compressor work, power, specific fuel consumption, heat rate) were...
Facility layout design for hybrid cellular manufacturing systems
July 2011
Facility layout which is the arrangement of facilities in the shop-floor has a great impact on the performance of manufacturing systems. An effective layout decreases material handling cost, throughput time, lead-time and results in increasing productivity and efficiency of manufacturing systems. Although layout problems have significant roles on the efficacy of manufacturing systems, scant attention has been...
Distributed flexible manufacturing system (FMS) scheduling using Memetic algorithm, particle swarm optimization and timed Petri net
July 2011
Allocating jobs to the best factories and scheduling them are two important problems in distributed flexible manufacturing systems that are among NP-hard problems. Many different intelligent algorithms have been proposed for these problems. In this paper, two new algorithms were proposed for distributed flexible manufacturing system (DFMS-MPN and DFMS-PPN algorithms), in which one of them was based on Memetic...
A study on improving the optimization process of a manufacturing run time problem with defective and machine breakdown
July 2011
This research note improves the optimization process of a manufacturing run time problem studied by Chiu et al. (2011) by presenting a direct proof of convexity of the long-run average cost function of such a problem. It can be used to replace Theorem 1 on conditional convexity given by Chiu et al. enhance quality of optimization process, and eliminate the computational efforts in verifying the...
Effects of polarization loss factor, form factors and reader transmitting power on the range of paper and plastic UHF tags in a free and metallic environment
June 2011
Passive RFID has come to dominate all facets of modern life and thereby making auto-identification a daily occurrence in our daily activities. From the complex application of nuclear waste tracking to supply chain management, RFID passive tags have come under various form factors ranging from paper to plastic tags. What determines what form factor to be used and best angle between the tag and the reader is analyzed in...
Compressed channel estimation for sparse multipath two-way relay networks
June 2011
Relay network was introduced to realize high-data rate transmission and high capacity with limited transmit power. However, channel state information (CSI) is needed due to the requirement from coherent data detection and the self-data removal at terminals in the two-way relay networks (TWRN). Traditional linear probing techniques are able to acquire the accurate CSI by using enough training sequence. However, they may...
Improvement of direct torque control in high power induction motors
June 2011
Matrix converter rather than voltage source inverter can be used as high-performance technique supplying electric motor in direct torque control (DTC). DTC’s most significant deficiency in induction motor, magnetic torque ripple, can be markedly reduced by appropriate space voltage-vectors whose influence on stator flux and electromagnetic torque in DTC of induction machine that uses “matrix converter”...
Video motion perception using optimized Gabor filter
June 2011
Motion estimation in image sequences is a fundamental issue in many applications as for instance in artificial vision and three-dimensional scene reconstruction. The basic problem of the recent spatio-temporal filtering techniques used in the perception of object motion from a time sequence of 2-D images is the computational burden. This is mainly due to the computation of the frequency responses of the images to the...
Performance evaluation of multirate filters for digital down converters
June 2011
For achieving maximum signal transfer without any noise in all available communication systems, the frequency of the processor is synchronized with the sampling rate of the signal. The use of multirate filtering allows designers to achieve this. In this paper, the multirate filters with and without compensation have been implemented very effectively using FPGA (field programmable gate arrays). Also, comparison of FIR...
Simulation and analysis of the harmonic behavior of matrix converters as compared with conventional converters
June 2011
The type of the electronic converter used in a set based on power electronics has an important role in the performance of the set. For example, the quality of the converter in the drive system of a motor has a direct influence on the performance of the motor. In recent studies, the use of matrix converters in the drive system of motors has yielded very desirable results. One of the most important positive aspects of...
Entropy production minimization in steady state heat conduction
June 2011
The rate of entropy generation during the steady conduction through a solid slab is investigated analytically. The effects of thermal conductivity and internal heat generation/sink on the total rate of entropy generation are discussed. Cases of uniform, spatial variable and temperature dependent thermal conductivity are considered. In addition, the case of introducing internal heat source/sink is discussed. It is...
Integration of reverse osmosis and refrigeration systems for energy efficient seawater desalination
June 2011
Reverse osmosis (RO) systems have minimum energy consumption compared to other desalination methods and their energy consumption is only in the form of electric power. However, in addition to fresh water, many buildings and even many factories and industries also need air conditioning, which requires large amounts of energy. The aim of this study was to introduce a new method for combined cold and fresh water (CCW)...
Stability analysis of a gradient elastic beam using ï¬nite element method
June 2011
Gradient elasticity models have been proposed in recent years in order to describe phenomena that cannot be described by classical elasticity models. In this contribution, the finite element model is conducted within the context of non-classical continuum mechanics, by introducing a material length scale parameter. The finite element method for the Euler-Bernoulli beam model is applied for the buckling analyzes of...
An experimental and modeling study of a dehumidification tower
June 2011
In this paper, the size and performance of a dehumidification tower were studied by simulating varying operating conditions. Based on the experimental results, this study presents the performance of a packed tower absorber for a lithium chloride desiccant dehumidification system. The effects of the main variables - airflow rate, liquid desiccant flow rate, and inlet air temperature on the rate of dehumidification were...
Effect of anode and size variations on the cathodic protection of mild steel in sea water and sulphuric acid
June 2011
The performance of different sizes of zinc, and aluminium galvanic anodes on the cathodic protection of mild steel in seawater and 0.2 M sulphuric acid was evaluated at ambient temperature. The magnitude of corrosion protection by the galvanic anodes was observed by weight loss method, corrosion rate calculation and potential measurement technique. It was observed that the aluminium anodes proved more...
Changes of hydraulic conductivity of silty clayey sand soil under the effects of municipal solid waste leachate
June 2011
Effect of municipal solid waste (MSW) on the hydraulic conductivity of soil is an important factor for designing liner systems. Leachate samples were collected within a landfill and a composting factory leachate lagoon. Soil samples from the bottom of the Esfahan, Iran, landfill were collected. Effects of the leachates on permeability of the soil samples were investigated. The results of study showed that at the...
Adaptive neuro-fuzzy inference system based model for rainfall forecasting in Klang River, Malaysia
June 2011
Runoff prediction still represents an extremely important issue in applied hydrology. On the other hand, rainfall is one of the most complicated effective hydrologic processes in runoff prediction. For a developing country such as Malaysia which is prone to flood disaster having such an expert model for runoff forecasting is a very vital matter. In this article, an adaptive neuro-fuzzy inference system (ANFIS)...
Effect of the physical parameters on the quality of Ordinary Portland cement of Jordan
June 2011
This study discusses different physical parameters of the Ordinary Portland cement (OPC) that is produced and available in Jordan, and their comparison with Jordan standard specifications which include Blaine, compressive strength at different ages, consistency, setting time and expansion. All the results are presented to provide both quantitative and qualitative notion of several locally produced ordinary Portland...
Neuroprotective effect of progesterone in newborn rats with hypoxic-ischemic encephalopathy
June 2011
Progesterone (PROG) is a type of neurosteroid, and it has physiological functions in the central nervous system. To date, most researches into progesterone have focused on its application in treatment of traumatic brain injury, stroke and neurodegenerative disorders, but its effect on hypoxic-ischemic encephalopathy (HIE) remains unclear. In the current study, we investigated the effect of exogenous progesterone in HIE...
Spirulina platensis extract supplementation attenuates oxidative stress in acute exhaustive exercise: A pilot study
June 2011
This study was performed to investigate the protective effect of Spirulina platensis extract (SPE) supplementation on oxidative stress in acute exhaustive exercise. The experiment was carried out on 8 male Wistar rats distributed into 4 groups (A, B, C, and D) of 20 rats each. The A group designated as control group were administered with placebo (saline) water by gavage every day for 6 weeks. The B, C and D group...
Monitoring land use/cover change and its effects in a higly urbanized district of a metropolitan city Istanbul, Turkey
June 2011
The utility of Landsat TM imagery for mapping land use/cover in Istanbul, Turkey is examined in this study. Urbanization has been the dominant demographic trend for the last few decades in Istanbul. The research focused especially to one of the biggest districts of Istanbul (Umraniye), which represents best the growing problems of urban sprawl. Umraniye district is exposed to rapid land use change over last few decades,...
Ammonia loss, soil exchangeable ammonium and available nitrate contents from mixing urea with zeolite and peat soil water under non-waterlogged condition
June 2011
Efficient utilization of urea-N in most agricultural systems is impeded by ammonia volatilization. This study investigated the effect of mixing urea with zeolite and peat soil water on ammonia volatilization, soil exchangeable ammonium and available nitrate contents, compared with urea without additives under non waterlogged condition. The mixtures significantly reduced ammonia loss by 5 to 14% compared with...
A new method for image encryption via standard rules of CA and logistic map function
June 2011
In this paper a hybrid model of cellular automata and chaotic signal is proposed for image encryption. In this method, 8-bits mask is used for changing the pixel gray level of main image. Every bit content is 0 or 1. For changing each pixel gray level, value of each bit of the mask is selected by one of the 256 cellular automat standard rules. One of the 256 cellular automat standard rules is...
Synthesis and evaluation of technical properties of butadiene anti bacterial copolymers binder on cotton/polyester blend fabric
June 2011
This paper reports preparation of four samples of styrene-acrylic emulsion copolymers. It was performed in the presence of acrylic-acid, acryl amid, ammonium persulfate as a free radical initiator and sodium dodecyl benzene sulfate as an anionic emulsifier at 80°C. The Ag nanoparticles were almost monodisperse in nature and their average diameter was approximately 12.5 nm. The fabric shows antibacterial activity...
The genetic algorithm to management measures of information security systems
June 2011
A novel genetic algorithm is proposed to improve the effectiveness of management measures of information security systems. In this work, the information security management measure is evaluated via simulation systems. The genetic algorithm is used to adjust the information security management measure, and obtains the satisfied information security management measure. The experimental results suggest that this...
Exact solution to longitudinal and t orsional oscillations of an electrically conducting second-grade fluid
June 2011
In this paper, an attempt has been made to solve the problem related to the motion of...
The modeling and optimization method of bi-level CARP-based express logistics system
June 2011
Express logistics problem is a typical optimization problem. Considering the macro-allocation optimization problem and the micro routing scheduling problem, a bi-level CARP-based optimization modeling which the objective is to determine a set of feasible vehicle trips of minimum total cost has been constructed to describe the express logistics problem. Furthermore, an optimization method has been proposed based on the...
Dynamics of a higher - order nonlinear rational difference equation
June 2011
In this paper, we consider the higher-order nonlinear rational difference equation , where the parameters and the initial conditions , . We investigate the periodic character, the invariant intervals and the global asymptotic stability of all positive solutions of the equation. Key words: Difference equation, stability, periodicity, invariant interval, global stability.
A mathematical model to determine the maximum end-to-end delay bound on label switched path for real time applications over mobile IPv6
June 2011
The real time applications have driven the demand for increasing and guaranteed bandwidth requirements in the network. Due to the mobility feature within a MN, mobile networks need a more sophisticated mechanism for quality of service provision. Beside, custom routing methods in a Mobile IPv6 network deliver a packet via specific tunnel this causes intermediate routers do not recognize content of a control packet due to...
Chlorophyll pigmentation and photosynthetic parameters in Ornithogalum longibracteatum L. as affected by varying temperatures in hydroponics solution
June 2011
The effects of different temperature regimes of hydroponic solution on the chlorophyll pigmentation and photosynthesis of Ornithogalum longibracteatum L. were determined in the glasshouse for 10 weeks in 2009 and 2010. The plants were irrigated with hydroponic solution, heated to various temperatures (26, 30 and 34°C) via pumps connected to 4 sets of water tanks, each maintained at the experimental...
Physical land suitability classification in a semi-arid condition: The Çiçekdaği State Farm-Kirsehir, Turkey
June 2011
Studies regarding land evaluation are based on the decision to land use according to their current potentials and to protect natural sources for the next generations. This study aims to determine the suitability and land use variations of the fields considering the characteristics of the soils in KirÅŸehir-ÇiçekdaÄŸ State Farm. Primarily, detailed soil mapping studies were carried, and subsequently, 20...
The role of the subtropical jet stream in cyclogenesis over the Central Mediterranean Sea: A case study of February 1974
June 2011
The Mediterranean Sea is recognized as one of the most important locations for cyclogenesis. In the course of this study, the role of subtropical jet stream in the formation of a deep cyclone over the central part of the Mediterranean Sea during 21 to 23, February 1974, was studied. The analysis based on NCEP data showed that there was a strong link between the presence of a subtropical jet...
Monitoring of shallow landslide in Tun Sardon 3.9 km Pinang Island, Malaysia
June 2011
The objective of this paper is to monitor the slope movement before a landslide occurrence. Inclinometer, piezometer and rain gauge were installed to monitor the slope. In the study area, water level of all piezometers is showing cyclic trend correlated with rainfall intensity. Observation made on July 30th 2010 and November 4th 2010 show soil movement in positive direction (towards slope). A relation between...
Mass media in Taiwan and the formation of Chien-Ming Wang’s baseball superstar image
June 2011
This study aims to analyze the methods used by mass media in Taiwan to manipulate the idolization of Chien-Ming Wang on his road to become a well-known Taiwanese baseball star using documentary analysis method and to further explore how Chien-Ming Wang had become the most famous star in Taiwan under the manipulation of mass media through marketing by interviewing some sports journalists and Wang’s sponsors. And it...
Reducing the peak to average power ratio in OFDM systems
June 2011
High peak to average power ratio of the transmit signal is a major drawback of OFDM systems. After defining the PAPR and analyzing its statistical properties, some of the most representative PAPR-reduction techniques available in the literature are reviewed in detail. Several methods have been proposed to reduce the peak power of...
The idolization of Chien-Ming Wang and social psychological factors in Taiwan
June 2011
This study aims to explore the relationship between the idolization of Chien-Ming Wang and the social psychological factors in Taiwan. Documentary analysis was applied to analyze the time and political background of baseball development in Taiwan. Also in-depth interviews with sports journalists in Taiwan, the CEO of the World Games 2009 in Kaohsiung, and Wang’s fans were conducted. It was found that Wang’s...
Look ahead dynamic threshold voltage control for enhanced write margin of 45 NM 7T-SRAM cell
June 2011
Instability of SRAM memory cells derived from aggressive technology scaling has recently been one of the most significant issues. Although a 7T–SRAM cell with an area tolerable separated read port improves read margins even at sub-1V, it unfortunately results in degradation of write margins. A new memory cell adopting a look ahead body-bias which dynamically controls the threshold voltage was proposed in...
Frequency synthesis techniques for high speed communication system
June 2011
The phase locked loop (PLL) has been widely used in wireless communication systems due to the high frequency resolution and the short locking time. In particular, it is possible to achieve a very high-frequency resolution together with fast settling and spectral purity. We used DDS and two types of PLLs analog as well as digital in our work. Though we gave a comparative results of PLLs used in our simulation based on...
EE-RI-MAC: An energy-efficient receiver-initiated asynchronous duty cycle MAC protocol for dynamic traffic loads in wireless sensor networks
June 2011
Introducing duty cycling in the MAC protocol used in wireless sensor networks has been proven to be an efficient way of prolonging the battery lifetime of the sensor nodes because idle listening is a high energy consumption factor. This concept has been proven efficient in the existing energy-efficient MAC protocols, including receiver-initiated MAC (RI-MAC). In this paper, we further enhance the RI-MAC protocol by...
Power amplifier- memory-less non linear modeling
June 2011
The power amplifier’s nonlinearity broadens the input signal’s bandwidth. This is known as spectral re-growth which is undesirable since it causes interference with adjacent channels. It also causes distortions within the signal bandwidth, which affects the bit error rate at the receiver. Most recent transmission schemes, such as wideband code division multiple access (WCDMA) or orthogonal frequency division...
Extracting of tropospheric scintillation propagation data from Ku-Band satellite beacon
June 2011
Satellite beacon measurements at 12.255 GHz with an elevation angle of 40.1° during concurrent rain attenuation and tropospheric scintillation are analyzed. The power spectra density of the beacon signal is presented and scintillation are extracted from the raw propagation beacon data using a high pass filter with a cutoff frequency ranging from 2 to 500 mHz. It was observed at low frequency (2 mHz) the presence of...
Study on corollary of seismic base isolation system on buildings with soft storey
June 2011
Soft storey buildings are characterized by having a storey which has a lot of open spaces. This soft storey creates a major weak point in an earthquake. Since soft stories are classically associated with retail spaces and parking garages, they are often on the lower stories of a building, which means that when they collapse, they can take the whole building down with them, causing serious structural damage which may...
Seismic risk analysis of Denizli (Southwest Turkey) region using different statistical models
June 2011
Risk analyses made in an area of seismic activity are of great importance in determining earthquake occurrence intervals and recurrence periods. Several methods, some of which include statistical methods, have been developed for this purpose. Gamma, Weibull distributions and Markov, Poisson, Gumbel are the most frequently used methods in this regard. In this study, instrumental records of 73 earthquakes of...
Effect of time elapse after wave hitting on coupled Spar platform
June 2011
Oil and gas exploration has moved from shallow to much deeper water now-a-days. Offshore compliant floating structure like Spar platforms in this region are competent deep water platform. As water depth increase operational Spar platforms experience more influence of mooring lines suggestively. So the motion analysis of platforms in deep waters requires counting the mooring upshot with spar hull. The most common...
Vibration and stability of multi-cracked beams under compressive axial loading
June 2011
In this study, a novel technique for the vibration and stability analyses of axially loaded beams with multi-cracks was offered. In the model which combines the finite element and component mode synthesis methods, the cracks were modelled as massless springs. Initially, stability analysis was completed and then three numerical cases were given to explore the effects of axial load levels, crack locations and ratios on...
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