Search results for: Static Security Assessment.
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 2991

Search results for: Static Security Assessment.

1701 Evaluation of Progressive Collapse of Transmission Tower

Authors: Jeong-Hwan Choi, Hyo-Sang Park, Tae-Hyung Lee

Abstract:

The transmission tower is one of the crucial lifeline structures in a modern society, and it needs to be protected against extreme loading conditions. However, the transmission tower is a very complex structure and, therefore, it is very difficult to simulate the actual damage and the collapse behavior of the tower structure. In this study, the actual collapse behavior of the transmission tower due to lateral loading conditions such as wind load is evaluated through the computational simulation. For that, a progressive collapse procedure is applied to the simulation. In this procedure, after running the simulation, if a member of the tower structure fails, the failed member is removed and the simulation run again. The 154kV transmission tower is selected for this study. The simulation is performed by nonlinear static analysis procedure, namely pushover analysis, using OpenSEES, an earthquake simulation platform. Three-dimensional finite element models of those towers are developed.

Keywords: Transmission tower, OpenSEES, pushover analysis, progressive collapse.

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1700 Feasibility Study of MongoDB and Radio Frequency Identification Technology in Asset Tracking System

Authors: Mohd Noah A. Rahman, Afzaal H. Seyal, Sharul T. Tajuddin, Hartiny Md Azmi

Abstract:

Taking into consideration the real time situation specifically the higher academic institutions, small, medium to large companies, public to private sectors and the remaining sectors, do experience the inventory or asset shrinkages due to theft, loss or even inventory tracking errors. This happening is due to a zero or poor security systems and measures being taken and implemented in their organizations. Henceforth, implementing the Radio Frequency Identification (RFID) technology into any manual or existing web-based system or web application can simply deter and will eventually solve certain major issues to serve better data retrieval and data access. Having said, this manual or existing system can be enhanced into a mobile-based system or application. In addition to that, the availability of internet connections can aid better services of the system. Such involvement of various technologies resulting various privileges to individuals or organizations in terms of accessibility, availability, mobility, efficiency, effectiveness, real-time information and also security. This paper will look deeper into the integration of mobile devices with RFID technologies with the purpose of asset tracking and control. Next, it is to be followed by the development and utilization of MongoDB as the main database to store data and its association with RFID technology. Finally, the development of a web based system which can be viewed in a mobile based formation with the aid of Hypertext Preprocessor (PHP), MongoDB, Hyper-Text Markup Language 5 (HTML5), Android, JavaScript and AJAX programming language.

Keywords: RFID, asset tracking system, MongoDB, NoSQL.

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1699 The Impact of Website Personality on Consumers' Initial Trust towards Online Retailing Websites

Authors: Jasmine Yeap Ai Leen, T. Ramayah, Azizah Omar

Abstract:

E-tailing websites are often perceived to be static, impersonal and distant. However, with the movement of the World Wide Web to Web 2.0 in recent years, these online websites have been found to display personalities akin to 'humanistic' qualities and project impressions much like its retailing counterpart i.e. salespeople. This paper examines the personality of e-tailing websites and their impact on consumers- initial trust towards the sites. A total of 239 Internet users participated in this field experiment study which utilized 6 online book retailers- websites that the participants had not previously visited before. Analysis revealed that out of four website personalities (sincerity, competence, excitement and sophistication) only sincerity and competence are able to exert an influence in building consumers- trust upon their first visit to the website. The implications of the findings are further elaborated in this paper.

Keywords: E-commerce, e-tailing, initial trust, online trust, partial least squares, website personality.

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1698 Intact and ACL-Deficient Knee MODEL Evaluation

Authors: A. Vairis, M. Petousis, B. Kandyla, C. Chrisoulakis

Abstract:

The human knee joint has a three dimensional geometry with multiple body articulations that produce complex mechanical responses under loads that occur in everyday life and sports activities. To produce the necessary joint compliance and stability for optimal daily function various menisci and ligaments are present while muscle forces are used to this effect. Therefore, knowledge of the complex mechanical interactions of these load bearing structures is necessary when treatment of relevant diseases is evaluated and assisting devices are designed. Numerical tools such as finite element analysis are suitable for modeling such joints in order to understand their physics. They have been used in the current study to develop an accurate human knee joint and model its mechanical behavior. To evaluate the efficacy of this articulated model, static load cases were used for comparison purposes with previous experimentally verified modeling works drawn from literature.

Keywords: biomechanics, finite element modeling, knee joint

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1697 Reduction of Leakage Power in Digital Logic Circuits Using Stacking Technique in 45 Nanometer Regime

Authors: P.K. Sharma, B. Bhargava, S. Akashe

Abstract:

Power dissipation due to leakage current in the digital circuits is a biggest factor which is considered specially while designing nanoscale circuits. This paper is exploring the ideas of reducing leakage current in static CMOS circuits by stacking the transistors in increasing numbers. Clearly it means that the stacking of OFF transistors in large numbers result a significant reduction in power dissipation. Increase in source voltage of NMOS transistor minimizes the leakage current. Thus stacking technique makes circuit with minimum power dissipation losses due to leakage current. Also some of digital circuits such as full adder, D flip flop and 6T SRAM have been simulated in this paper, with the application of reduction technique on ‘cadence virtuoso tool’ using specter at 45nm technology with supply voltage 0.7V.

Keywords: Stack, 6T SRAM cell, low power, threshold voltage

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1696 Improving the Performance of Deep Learning in Facial Emotion Recognition with Image Sharpening

Authors: Ksheeraj Sai Vepuri, Nada Attar

Abstract:

We as humans use words with accompanying visual and facial cues to communicate effectively. Classifying facial emotion using computer vision methodologies has been an active research area in the computer vision field. In this paper, we propose a simple method for facial expression recognition that enhances accuracy. We tested our method on the FER-2013 dataset that contains static images. Instead of using Histogram equalization to preprocess the dataset, we used Unsharp Mask to emphasize texture and details and sharpened the edges. We also used ImageDataGenerator from Keras library for data augmentation. Then we used Convolutional Neural Networks (CNN) model to classify the images into 7 different facial expressions, yielding an accuracy of 69.46% on the test set. Our results show that using image preprocessing such as the sharpening technique for a CNN model can improve the performance, even when the CNN model is relatively simple.

Keywords: Facial expression recognition, image pre-processing, deep learning, CNN.

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1695 Wavelet Entropy Based Algorithm for Fault Detection and Classification in FACTS Compensated Transmission Line

Authors: Amany M. El-Zonkoly, Hussein Desouki

Abstract:

Distance protection of transmission lines including advanced flexible AC transmission system (FACTS) devices has been a very challenging task. FACTS devices of interest in this paper are static synchronous series compensators (SSSC) and unified power flow controller (UPFC). In this paper, a new algorithm is proposed to detect and classify the fault and identify the fault position in a transmission line with respect to a FACTS device placed in the midpoint of the transmission line. Discrete wavelet transformation and wavelet entropy calculations are used to analyze during fault current and voltage signals of the compensated transmission line. The proposed algorithm is very simple and accurate in fault detection and classification. A variety of fault cases and simulation results are introduced to show the effectiveness of such algorithm.

Keywords: Entropy calculation, FACTS, SSSC, UPFC, wavelet transform.

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1694 Household Food Insecurity and Associated Coping Strategies in Urban, Peri-Urban and Rural Settings: A Case of Morogoro and Iringa Towns, Tanzania

Authors: U. Tumaini, J. Msuya

Abstract:

Food insecurity is a worrying challenge worldwide with sub-Saharan Africa including Tanzania being the most affected. Although factors that influence household food access security status and ways of coping with such factors have been examined, little has been reported on how these coping strategies vary along the urban-rural continuum especially in medium-sized towns. The purpose of this study was to identify food insecurity coping strategies employed by households and assess whether they are similar along the urban-rural continuum. The study was cross-sectional in design whereby a random sample of 279 households was interviewed using structured questionnaire. Data were analysed using Statistical Package for Social Sciences (SPSS) Version 20 software. It was revealed that the proportion of households relying on less preferred and quality foods, eating fewer meals per day, undertaking work for food or money, performing farm and off-farm activities, and selling fall back assets was higher in rural settings compared to urban and peri-urban areas. Similarly, more households in urban and peri-urban areas cope with food access insecurity by having strict food budgets compared to those in rural households (p ≤ 0.001). The study concludes that food insecurity coping strategies vary significantly from one spatial entity to another. It is thereby recommended that poor, particularly rural households should be supported to diversify their income-generating activities not only for food security purposes during times of food shortage but also as businesses aimed at increasing their household incomes.

Keywords: Food coping strategies, household food insecurity, medium-sized towns, urban-rural continuum.

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1693 Hybrid Algorithm for Hammerstein System Identification Using Genetic Algorithm and Particle Swarm Optimization

Authors: Tomohiro Hachino, Kenji Shimoda, Hitoshi Takata

Abstract:

This paper presents a method of model selection and identification of Hammerstein systems by hybridization of the genetic algorithm (GA) and particle swarm optimization (PSO). An unknown nonlinear static part to be estimated is approximately represented by an automatic choosing function (ACF) model. The weighting parameters of the ACF and the system parameters of the linear dynamic part are estimated by the linear least-squares method. On the other hand, the adjusting parameters of the ACF model structure are properly selected by the hybrid algorithm of the GA and PSO, where the Akaike information criterion is utilized as the evaluation value function. Simulation results are shown to demonstrate the effectiveness of the proposed hybrid algorithm.

Keywords: Hammerstein system, identification, automatic choosing function model, genetic algorithm, particle swarm optimization.

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1692 Greenhouse Gas Emissions from a Tropical Eutrophic Freshwater Wetland

Authors: Juan P. Silva, T. R. Canchala, H. J. Lubberding, E. J. Peña, H. J. Gijzen

Abstract:

This study measured the fluxes of greenhouse gases (GHGs) i.e. CO2, CH4 and N2O from a tropical eutrophic freshwater wetland (“Sonso Lagoon”) which receives input loading nutrient from several sources i.e. agricultural run-off, domestic sewage, and a polluted river. The flux measurements were carried out at four different points using the static chamber technique. CO2 fluxes ranged from -8270 to 12210 mg.m-2.d-1 (median = 360; SD = 4.11; n = 50), CH4 ranged between 0.2 and 5270 mg.m-2.d-1 (median = 60; SD = 1.27; n = 45), and N2O ranged from -31.12 to 15.4 mg N2O m-2.d-1 (median = 0.05; SD = 9.36; n = 42). Although some negative fluxes were observed in the zone dominated by floating plants i.e. Eichornia crassipes, Salvinia sp., and Pistia stratiotes L., the mean values indicated that the Sonso Lagoon was a net source of CO2, CH4 and N2O. In addition, an effect of the eutrophication on GHG emissions could be observed in the positive correlation found between CO2, CH4 and N2O generation and COD, PO4-3, NH3-N, TN and NO3-N. The eutrophication impact on GHG production highlights the necessity to limit the anthropic activities on freshwater wetlands.

Keywords: Eutrophication, greenhouse gas emissions, freshwater wetlands, climate change.

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1691 Modeling the Transport of Charge Carriers in the Active Devices MESFET, Based of GaInP by the Monte Carlo Method

Authors: N. Massoum, A. Guen. Bouazza, B. Bouazza, A. El Ouchdi

Abstract:

The progress of industry integrated circuits in recent years has been pushed by continuous miniaturization of transistors. With the reduction of dimensions of components at 0.1 micron and below, new physical effects come into play as the standard simulators of two dimensions (2D) do not consider. In fact the third dimension comes into play because the transverse and longitudinal dimensions of the components are of the same order of magnitude. To describe the operation of such components with greater fidelity, we must refine simulation tools and adapted to take into account these phenomena. After an analytical study of the static characteristics of the component, according to the different operating modes, a numerical simulation is performed of field-effect transistor with submicron gate MESFET GaInP. The influence of the dimensions of the gate length is studied. The results are used to determine the optimal geometric and physical parameters of the component for their specific applications and uses.

Keywords: Monte Carlo simulation, transient electron transport, MESFET device.

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1690 Processor Scheduling on Parallel Computers

Authors: Mohammad S. Laghari, Gulzar A. Khuwaja

Abstract:

Many problems in computer vision and image processing present potential for parallel implementations through one of the three major paradigms of geometric parallelism, algorithmic parallelism and processor farming. Static process scheduling techniques are used successfully to exploit geometric and algorithmic parallelism, while dynamic process scheduling is better suited to dealing with the independent processes inherent in the process farming paradigm. This paper considers the application of parallel or multi-computers to a class of problems exhibiting spatial data characteristic of the geometric paradigm. However, by using processor farming paradigm, a dynamic scheduling technique is developed to suit the MIMD structure of the multi-computers. A hybrid scheme of scheduling is also developed and compared with the other schemes. The specific problem chosen for the investigation is the Hough transform for line detection.

Keywords: Hough transforms, parallel computer, parallel paradigms, scheduling.

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1689 Developing Leadership and Teamwork Skills of Pre-Service Teacher through Learning Camp

Authors: Sirimanee Banjong

Abstract:

This study aimed to 1) develop pre-service teachers’ leadership skills through camp-based learning, and 2) develop preservice teachers’ teamwork skills through camp-based learning. An applied research methodology was used. The target group was derived from a purposive selection. It involved 32 fourth-year students in Early Childhood Education Program enrolling a course entitled Seminar in Early Childhood Education provided during second semester of academic year 2013. The treatment was camp-based learning activities which applied a PDCA process including four stages: 1) plan, 2) do, 3) check, and 4) act. Research instruments were a learning camp program, a camp-based learning management plan, a 5-level assessment form for leadership skills and a 5-level assessment form for assessing teamwork skills. Data were analyzed using descriptive statistics. Results were: 1) pre-service teachers’ leadership skills yielded the before treatment average score at x= 3.4, S.D.=0.6 2and the after-treatment average score at x 4.29 , S.D.=0.66 pre-service teachers’ teamwork skills yielded the before-treatment average score at x=3.31, S.D.=0.60 and the after-treatment average score at x=4.42, S.D.=0.66 Both differences were statistically significant at the .05 level. Thus, the pre-service teachers’ leadership and teamwork skills were significantly improved through the camp-based learning approach.

Keywords: Learning camp, leadership skills, teamwork skills.

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1688 Design and Analysis of a Low Power High Speed 1 Bit Full Adder Cell Based On TSPC Logic with Multi-Threshold CMOS

Authors: Ankit Mitra

Abstract:

An adder is one of the most integral component of a digital system like a digital signal processor or a microprocessor. Being an extremely computationally intensive part of a system, the optimization for speed and power consumption of the adder is of prime importance. In this paper we have designed a 1 bit full adder cell based on dynamic TSPC logic to achieve high speed operation. A high threshold voltage sleep transistor is used to reduce the static power dissipation in standby mode. The circuit is designed and simulated in TSPICE using TSMC 180nm CMOS process. Average power consumption, delay and power-delay product is measured which showed considerable improvement in performance over the existing full adder designs.

Keywords: CMOS, TSPC, MTCMOS, ALU, Clock gating, power gating, pipelining.

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1687 Seismic Directionality Effects on In-Structure Response Spectra in Seismic Probabilistic Risk Assessment

Authors: S. Jarernprasert, E. Bazan-Zurita, P. C. Rizzo

Abstract:

Currently, seismic probabilistic risk assessments (SPRA) for nuclear facilities use In-Structure Response Spectra (ISRS) in the calculation of fragilities for systems and components. ISRS are calculated via dynamic analyses of the host building subjected to two orthogonal components of horizontal ground motion. Each component is defined as the median motion in any horizontal direction. Structural engineers applied the components along selected X and Y Cartesian axes. The ISRS at different locations in the building are also calculated in the X and Y directions. The choice of the directions of X and Y are not specified by the ground motion model with respect to geographic coordinates, and are rather arbitrarily selected by the structural engineer. Normally, X and Y coincide with the “principal” axes of the building, in the understanding that this practice is generally conservative. For SPRA purposes, however, it is desirable to remove any conservatism in the estimates of median ISRS. This paper examines the effects of the direction of horizontal seismic motion on the ISRS on typical nuclear structure. We also evaluate the variability of ISRS calculated along different horizontal directions. Our results indicate that some central measures of the ISRS provide robust estimates that are practically independent of the selection of the directions of the horizontal Cartesian axes.

Keywords: Seismic, Directionality, In-Structure Response Spectra, Probabilistic Risk Assessment.

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1686 The Two Layers of Food Safety and GMOs in the Hungarian Agricultural Law

Authors: Gergely Horváth

Abstract:

The study presents the complexity of food safety dividing it into two layers. Beyond the basic layer of requirements, there is a more demanding higher level linked with quality and purity aspects. It would be important to give special prominence to both layers, given that massive illnesses are caused by foods even though officially licensed. Then the study discusses an exciting safety challenge stemming from the risks of genetically modified organisms (GMOs). Furthermore, it features legal case examples that illustrate how certain liability questions are solved or not yet decided in connection with the production of genetically modified crops. In addition, a special kind of land grabbing, more precisely land grabbing from non-GMO farming systems can also be noticed as well as a new phenomenon eroding food sovereignty. Coexistence, the state where organic, conventional, and GM farming systems are standing alongside each other is an unsuitable experiment that cannot be successful, because of biophysical reasons (such as cross-pollination). Agricultural and environmental lawyers both try to find the optimal solution. Agri-environmental measures are introduced as a special subfield of law maintaining also food safety. The important steps of agri-environmental legislation are aiming at the protection of natural values, the environmental media and strengthening food safety as well, practically the quality of agricultural products intended for human consumption. The major findings of the study focus on searching for the appropriate approach capable of solving the security and safety problems of food production. The most interesting concepts of the Hungarian national and EU food law legislation are analyzed in more detail with descriptive, analytic and comparative methods.

Keywords: Food law, food safety, food security, GMO, agri-environmental measures.

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1685 Active Imagination: The Effective Factor in the Practice of Psychotherapy

Authors: Sonia Regina Lyra

Abstract:

The desire for unequivocal clarity is understandable, but this can make one forget that things of the soul are experiential processes, or transformations, which should never be designated unilaterally if it is not wanted to transform something that moves, a living thing, into something static. Among the so-called ‘things of the soul’ there are especially spontaneous fantasies, that emerge during the processes, as a result from the use of the active imagination technique, for when fantasy is not forced, violated, or subjugated by an illegitimate, intellectually preconceived idea, then it is a legitimate and authentic product of the unconscious mind. This is how one can gain access to unadulterated information about everything that transcends the conscious mind. However, it is vital to discern between ego and non-ego, because this principle will result in a release of energy and a renewal of life, which will come to have meaning. This study will deal with the active imagination as a knowledge that depends on the individual experience of the therapist because the patient will be taken just to reach where the unconscious of the therapist was assimilated to his own conscience. In this way, the therapist becomes the method itself, being his personality, a fundamental part of an effective factor.

Keywords: Active imagination, effective factor, symptom, transformation.

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1684 The Study of Implications on Modern Businesses Performances by Digital Communities: Case of Data Leak

Authors: Asim Majeed, Anwar Ul Haq, Mike, Lloyd-Williams, Arshad Jamal, Usman Butt

Abstract:

This study aims to investigate the impact of data leak of M&S customers on digital communities. Modern businesses are using digital communities as an important public relations tool for marketing purposes. This form of communication helps companies to build better relationship with their customers which also act as another source of information. The communication between the customers and the organizations is not regulated so users may post positive and negative comments. There are new platforms being developed on a daily basis and it is very crucial for the businesses to not only get themselves familiar with those but also know how to reach their existing and perspective consumers. The driving force of marketing and communication in modern businesses is the digital communities and these are continuously increasing and developing. This phenomenon is changing the way marketing is conducted. The current research has discussed the implications on M&S business performance since the data was exploited on digital communities; users contacted M&S and raised the security concerns. M&S closed down its website for few hours to try to resolve the issue. The next day M&S made a public apology about this incidence. This information was proliferated on various digital communities and it has impacted negatively on M&S brand name, sales and customers. The content analysis approach is being used to collect qualitative data from 100 digital bloggers including social media communities such as Facebook and Twitter. The results and finding provide useful new insights into the nature and form of security concerns of digital users. Findings have theoretical and practical implications. This research will showcase a large corporation utilizing various digital community platforms and can serve as a model for future organizations.

Keywords: Digital, communities, performance, dissemination, implications, data, exploitation.

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1683 Evaluation of Behavior Factor for Steel Moment-Resisting Frames

Authors: Taïeb Branci, Djamal Yahmi, Abdelhamid Bouchair, Eric Fourneley

Abstract:

According to current seismic codes the structures are calculated using the capacity design procedure based on the concept of shear at the base depending on several parameters including behavior factor which is considered to be the most important parameter. The behavior factor allows designing the structure when it is at its ultimate limit state taking into account its energy dissipation through its plastic deformation. The aim of the present study is to assess the basic parameters on which is composed the behavior factor among them the reduction factor due to ductility, and those due to redundancy and the overstrength for steel moment-resisting frames of different heights and regular configuration. Analyses are conducted on these frames using the nonlinear static method where the effect of some parameters on the behavior factor, such as the number of stories and the number of spans, are taken into account. The results show that the behavior factor is rather sensitive to the variation of the number of stories and bays.

Keywords: Behavior, code, frame, ductility, overstrength, redundancy, plastic.

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1682 Evaluation of Food Safety Management Systems of Food Service Establishments within the Greater Accra Region

Authors: Benjamin Osei-Tutu

Abstract:

Food contaminated with biological, chemical and physical hazards usually leads to foodborne illnesses which in turn increase the disease burden of developing and developed economies. Restaurants play a key role in the food service industry and violations in application of standardized food safety management systems in these establishments have been associated with foodborne disease outbreaks. This study was undertaken to assess the level of compliance to the Code of practice that was developed and implemented after conducting needs assessment of the food safety management systems employed by the Food Service Establishments in Ghana. Data on pre-licence inspections were reviewed to assess the compliance of the Food Service Establishments. During the period under review (2012-2016), 74.52% of the food service facilities in the hospitality industry were in compliance with the FDA’s code of practice. Main violations observed during the study bordered on facility layout and fabrication (61.8%) and this is because these facilities may not have been built for use as a food service establishment. Another fact that came to the fore was that the redesigning of the facilities to bring them into compliance required capital intensive investments, which some establishments are not prepared for. Other challenges faced by the industry regarded issues on records and documentations, personnel facilities and hygiene, raw materials acquisition, storage and control, and cold storage.

Keywords: Assessment, Accra, food safety management systems, restaurants, hotel.

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1681 An Adversarial Construction of Instability Bounds in LIS Networks

Authors: Dimitrios Koukopoulos

Abstract:

In this work, we study the impact of dynamically changing link slowdowns on the stability properties of packetswitched networks under the Adversarial Queueing Theory framework. Especially, we consider the Adversarial, Quasi-Static Slowdown Queueing Theory model, where each link slowdown may take on values in the two-valued set of integers {1, D} with D > 1 which remain fixed for a long time, under a (w, ¤ü)-adversary. In this framework, we present an innovative systematic construction for the estimation of adversarial injection rate lower bounds, which, if exceeded, cause instability in networks that use the LIS (Longest-in- System) protocol for contention-resolution. In addition, we show that a network that uses the LIS protocol for contention-resolution may result in dropping its instability bound at injection rates ¤ü > 0 when the network size and the high slowdown D take large values. This is the best ever known instability lower bound for LIS networks.

Keywords: Network stability, quality of service, adversarial queueing theory, greedy scheduling protocols.

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1680 Bose-Einstein Condensation in Neutral Many Bosonic System

Authors: M. Al-Sugheir, M. Sakhreya, G. Alna'washi, F. Al-Dweri

Abstract:

In this work, the condensation fraction and transition temperature of neutral many bosonic system are studied within the static fluctuation approximation (SFA). The effect of the potential parameters such as the strength and range on the condensate fraction was investigated. A model potential consisting of a repulsive step potential and an attractive potential well was used. As the potential strength or the core radius of the repulsive part increases, the condensation fraction is found to be decreased at the same temperature. Also, as the potential depth or the range of the attractive part increases, the condensation fraction is found to be increased. The transition temperature is decreased as the potential strength or the core radius of the repulsive part increases, and it increases as the potential depth or the range of the attractive part increases.

Keywords: About four key words or phrases in alphabetical order, separated by commas

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1679 Pre-Service Teachers’ Assessment of Information Technology Application to Instruction

Authors: Adesanya Anuoluwapo Olusola

Abstract:

Technology has moved into the classroom, and it becomes difficult talking of achievement in and attitude to learning without making mention of it. The use of technology makes learning easy, real and practical as it motivates learners, sustains their interest and improves their attitude to learning. This study, therefore examined the pre-service teachers’ assessment of information technology application to instruction. The use of technology emphasizes and encourages active learning in the classroom. The study involved 100 pre-service teachers in the selected two (2) Colleges of Education, Nigeria. Purposive random sampling was used in selecting the participants and ex-post facto design was adopted the in which there is no manipulation of variables. Two valid and reliable instruments were used for data collection: Access Point ICT facilities and Application of ICT. The study established that pre-service teachers have less access to ICT facilities and Application of ICT in the college, apart from those students having the access outside the college. Also fewer pre-service teachers used ICT facilities on weekly and monthly bases. It was concluded that the establishment of students’ resources centres and Campus wide wireless connectivity must be implemented so as to improve and enhance students’ achievement in and attitude to learning. The time and attention devoted to learning activities and strategic specialized ICT skills and requisite entrepreneur skills should be increased so as to have easy access to information sources and be able to apply it in teaching process.

Keywords: Computer, ICT Application, Learning Facilities, Pre-Service Teachers.

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1678 The Risk Assessment of Nano-particles and Investigation of Their Environmental Impact

Authors: Nader Nabhani, Amir Tofighi

Abstract:

Nanotechnology is the science of creating, using and manipulating objects which have at least one dimension in range of 0.1 to 100 nanometers. In other words, nanotechnology is reconstructing a substance using its individual atoms and arranging them in a way that is desirable for our purpose. The main reason that nanotechnology has been attracting attentions is the unique properties that objects show when they are formed at nano-scale. These differing characteristics that nano-scale materials show compared to their nature-existing form is both useful in creating high quality products and dangerous when being in contact with body or spread in environment. In order to control and lower the risk of such nano-scale particles, the main following three topics should be considered: 1) First of all, these materials would cause long term diseases that may show their effects on body years after being penetrated in human organs and since this science has become recently developed in industrial scale not enough information is available about their hazards on body. 2) The second is that these particles can easily spread out in environment and remain in air, soil or water for very long time, besides their high ability to penetrate body skin and causing new kinds of diseases. 3) The third one is that to protect body and environment against the danger of these particles, the protective barriers must be finer than these small objects and such defenses are hard to accomplish. This paper will review, discuss and assess the risks that human and environment face as this new science develops at a high rate.

Keywords: Nanotechnology, risk assessment, environment.

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1677 Image Classification and Accuracy Assessment Using the Confusion Matrix, Contingency Matrix, and Kappa Coefficient

Authors: F. F. Howard, C. B. Boye, I. Yakubu, J. S. Y. Kuma

Abstract:

One of the ways that could be used for the production of land use and land cover maps by a procedure known as image classification is the use of the remote sensing technique. Numerous elements ought to be taken into consideration, including the availability of highly satisfactory Landsat imagery, secondary data and a precise classification process. The goal of this study was to classify and map the land use and land cover of the study area using remote sensing and Geospatial Information System (GIS) analysis. The classification was done using Landsat 8 satellite images acquired in December 2020 covering the study area. The Landsat image was downloaded from the USGS. The Landsat image with 30 m resolution was geo-referenced to the WGS_84 datum and Universal Transverse Mercator (UTM) Zone 30N coordinate projection system. A radiometric correction was applied to the image to reduce the noise in the image. This study consists of two sections: the Land Use/Land Cover (LULC) and Accuracy Assessments using the confusion and contingency matrix and the Kappa coefficient. The LULC classifications were vegetation (agriculture) (67.87%), water bodies (0.01%), mining areas (5.24%), forest (26.02%), and settlement (0.88%). The overall accuracy of 97.87% and the kappa coefficient (K) of 97.3% were obtained for the confusion matrix. While an overall accuracy of 95.7% and a Kappa coefficient of 0.947 were obtained for the contingency matrix, the kappa coefficients were rated as substantial; hence, the classified image is fit for further research.

Keywords: Confusion Matrix, contingency matrix, kappa coefficient, land used/ land cover, accuracy assessment.

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1676 Study of Effect of Removal of Shiftrows and Mixcolumns Stages of AES and AES-KDS on their Encryption Quality and Hence Security

Authors: Krishnamurthy G N, V Ramaswamy

Abstract:

This paper demonstrates the results when either Shiftrows stage or Mixcolumns stage and when both the stages are omitted in the well known block cipher Advanced Encryption Standard(AES) and its modified version AES with Key Dependent S-box(AES-KDS), using avalanche criterion and other tests namely encryption quality, correlation coefficient, histogram analysis and key sensitivity tests.

Keywords: Encryption, Decryption, Avalanche, keysensitivity.

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1675 Survey of Key Management Algorithms in WiMAX

Authors: R. Chithra, B. Kalavathi, J. Christy Lavanya

Abstract:

WiMAX is a telecommunications technology and it is specified by the Institute of Electrical and Electronics Engineers Inc., as the IEEE 802.16 standard. The goal of this technology is to provide a wireless data over long distances in a variety of ways. IEEE 802.16 is a recent standard for mobile communication. In this paper, we provide an overview of various key management algorithms to provide security for WiMAX.

Keywords: Broadcast, Rekeying, Scalability, Secrecy, Unicast, WiMAX.

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1674 Modeling and Simulation of Axial Fan Using CFD

Authors: Hemant Kumawat

Abstract:

Axial flow fans, while incapable of developing high pressures, they are well suitable for handling large volumes of air at relatively low pressures. In general, they are low in cost and possess good efficiency, and can have blades of airfoil shape. Axial flow fans show good efficiencies, and can operate at high static pressures if such operation is necessary. Our objective is to model and analyze the flow through AXIAL FANS using CFD Software and draw inference from the obtained results, so as to get maximum efficiency. The performance of an axial fan was simulated using CFD and the effect of variation of different parameters such as the blade number, noise level, velocity, temperature and pressure distribution on the blade surface was studied. This paper aims to present a final 3D CAD model of axial flow fan. Adapting this model to the available components in the market, the first optimization was done. After this step, CFX flow solver is used to do the necessary numerical analyses on the aerodynamic performance of this model. This analysis results in a final optimization of the proposed 3D model which is presented in this article.

Keywords: ANSYS CFX, Axial Fan, Computational Fluid Dynamics (CFD), Optimization.

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1673 Experimental Studies on Multiphase Flow in Porous Media and Pore Wettability

Authors: Xingxun Li, Xianfeng Fan

Abstract:

Multiphase flow transport in porous medium is very common and significant in science and engineering applications. For example, in CO2 Storage and Enhanced Oil Recovery processes, CO2 has to be delivered to the pore spaces in reservoirs and aquifers. CO2 storage and enhance oil recovery are actually displacement processes, in which oil or water is displaced by CO2. This displacement is controlled by pore size, chemical and physical properties of pore surfaces and fluids, and also pore wettability. In this study, a technique was developed to measure the pressure profile for driving gas/liquid to displace water in pores. Through this pressure profile, the impact of pore size on the multiphase flow transport and displacement can be analyzed. The other rig developed can be used to measure the static and dynamic pore wettability and investigate the effects of pore size, surface tension, viscosity and chemical structure of liquids on pore wettability.

Keywords: Enhanced oil recovery, Multiphase flow, Pore size, Pore wettability

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1672 A Numerical Investigation on the Dynamic Stall of a Wind Turbine Section Using Different Turbulent Models

Authors: S. A. Ahmadi, S. Sharif, R. Jamshidi

Abstract:

In this article, the flow behavior around a NACA 0012 airfoil which is oscillating with different Reynolds numbers and in various amplitudes has been investigated numerically. Numerical simulations have been performed with ANSYS software. First, the 2- D geometry has been studied in different Reynolds numbers and angles of attack with various numerical methods in its static condition. This analysis was to choose the best turbulent model and comparing the grids to have the optimum one for dynamic simulations. Because the analysis was to study the blades of wind turbines, the Reynolds numbers were not arbitrary. They were in the range of 9.71e5 to 22.65e5. The angle of attack was in the range of -41.81° to 41.81°. By choosing the forward wind speed as the independent parameter, the others like Reynolds and the amplitude of the oscillation would be known automatically. The results show that the SST turbulent model is the best choice that leads the least numerical error with respect the experimental ones. Also, a dynamic stall phenomenon is more probable at lower wind speeds in which the lift force is less.

Keywords: Dynamic stall, Numerical simulation, Wind turbine, Turbulent Model

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