Volume 5, Issue 12, December 2014 Edition

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Microcontroller Based Solar Tracking System and its Implementation[ ]


Sun is a very abundant source of power. Even so, only a fraction of the entire energy is harnessed and that too not efficiently. The main cause of this is the high cost of installation of solar cells. Also solar cells are mostly kept fixed, so they do not obtain the optimum amount of sunlight throughout the day.A new micro-controller based solar-tracking system is proposed implemented and tested. The scheme presented here can be operated as independent of the geographical location of the site of setting up. The system checks the position of the sun and controls the movement of a solar panel so that radiation of the sun comes normally to the surface of the solar panel. The developed-tracking system tracks the sun in the single plane. PC based system monitoring facility is also included in the design. In this paper we have proposed a single axis tracker for our discussions. This avoids the complexity of construction and usage

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Analyzing Difference Mechanical Vibrations Effect between Male and Female to Psychological Responses[ ]


Vibrations can be exposed to human in the form of Whole Body Vibration (WBV) or Tool Hand Vibration (THV). This study explored how difference mechanical vibrations affect between men and women to cognitive and psychological aspects. The value of the acceleration was obtained from the value of Root Mean Square (rms) of acceleration which is the square root of the squares of the three directions of vibration. Ten male and ten female respondents participated in this study, each worked with a computer on a simulator and was exposed to WBV. This research will analyze effects of vibrate and noisy condition to human and explore difference effects of that condition to male and female. Based on the research vibration and noise will effect mental workload of male and female altogether. Human mental workload is higher in vibrate and noisy condition. Mental workload increase from level light to level moderate on NASA TLX scale. Meanwhile there is not difference effect of vibrate and noisy condition between male and female.

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POWER FACTOR CORRECTION OF SINGLE PHASE RECTIFIER BASED ON TWO QUADRANT SHUNT ACTIVE FILTER[ ]


This paper presents a new technique to improve the input power factor of a single-phase rectifier with output inductor, based on a two-quadrant shunt active power filter. This is based on a conventional bidirectional DC-DC converter, which is connected to the output side of the diode bridge. Shunt active power filters consist of a power electronic converter which injects a compensating current to the grid, with the harmonic contents equal to the nonlinear load, but with opposite phase, resulting in a sinusoidal grid current, in phase with the voltage achieving an unity input power factor. The active power filter to this rectifier topology enabled the extension of the rectifier operation range in the continuous conduction mode with regulated output voltage. Circuit description, operation principle, modelling, design and simulation results are presented in this paper.

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The Application of ANFIS-PSO trained in Signal Propagation Modeling for Indoor Wireless Communication Networks; A Review.[ ]


Recently there has been heightened interest on wireless communication networks which is evident in the introduction and use of mobile telephony starting with 1G, 2G, 3G and 4G and wireless LANs. For instance currently in almost every company we can see wireless routers installed in several locations to make access to information much better. The same case happens to mobile phone use which is expected to reach approximately eight billion subscribers by end of 2016. Studies are concentrated on outdoor and indoor propagation of signals where researchers look into proper planning and investigation of signal propagation modelling. Because of the high demand for wireless communication systems, there is need for the researchers to develop accurate propagation models in order to provide better quality of service to the users more so in the outdoor to indoor channels since it is believed that most communication presently and in the future is expected to originate from indoor locations.

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EFFECTS OF SOWING TIME ON YIELD, GOT AND FIBER TRAITS OF UPLAND COTTON (GOSSYPIUM HIRSUTUM L.)[ ]


The study was conducted during cotton season 2014-15 at Central Cotton Research Institute Sakrand to investigate the appropriate time and influence of sowing dates on yield, GOT and fiber traits of upland cotton. The yield attributes; viz. bolls per plant, seed index, boll weight, seedcotton yield, ginning outturn and fiber quality parameters, staple length, fiber fineness and fiber strength was affected highly significant against sowing dates and varieties. The bolls per plant and boll weight were non significant as interaction between sowing date into varieties. The result suggested that cotton crop sown from 1st May given highest results for yield attributing traits seedcotton yield, bolls per plant, boll weight, seed index, whereas it gradually decreased after 30 days interval, when crop sowing late. As regards the fiber quality parameters staple length, fiber fineness and fiber strength also obtained highest values on 1st May sowing, latter on it reduced when crop sowing late on 1st June after 30 days interval.

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Isolation and screening of actinomycetes from marine samples for enzyme production[ ]


Many of the ecological factors of the marine environment were helpful in developing a strategy for discovering useful bioactive agents from marine microorganisms. Among them actinomycetes have gained special importance as they play a major role in recycling of organic matter, production of novel pharmaceuticals, cosmetics, enzymes, antitumor agents, enzyme inhibitors, immune-modifiers and vitamins. The present study was carried out to isolate actinomycetes, which have potential to produce enzymes from selected marine samples. A total of twenty actinomycetes were isolated and were characterized morphologically. Screening test was performed to determine cellulase, protease and lipase activity. Almost all the isolates showed maximum enzyme production.

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Visual Interface to Assess the Human Memory Organization in HCI[ ]


Memory is the fundamental component of humans as well as systems. In the computer system the memory is organised in well organised format and all the elements are suited according to the applications and desired output. Similar classification is also been used for the human memory as described by different psychologists. In this article we categorize the stages of human memory and their conversion from one stage to another as used for direct interaction with computer system. The categorization of memory has basic form as sensor memory and intermediate form as short term memory and final stage as long term memory used to describe the realistic phenomenon of memory organization. We create an interface to categorize the users’ memory in various memory forms by using the applications of lookalike images and identifying whether the images are similar or having some difference as identified by the human memory and recorded the time taken by the user. We also conclude our proposal in by defining the terminology used for transformation of one form of memory into other and its future application.

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Training Outcomes of Designed Yogic Practices on Respiratory Parameters among Female Students[ ]


The intention of the study is to find out the effects of yogic practices on selected Physiological variables on respiratory parameters; Breath Holding Time, Maximum Inspiratory Volume, Peak Flow Rate.Thirty randomly selected female students of engineering Periyar Maniammai University, Vallam, Thanjavur, Tamil nadu, India aged 17 –19 years, volunteered to participate in the study. Subjects were assigned into two groups: A (experimental: N-15) and B (control: N-15). The subjects from Group A were subjected to a 12-week yoga training programme. Each yoga session consisted of 15 minutes of dynamic warm-up exercises, 40 minutes of asanas , 10 minutes of pranayamas and 10 minutes of relaxation. The subjects were evaluated pre and post the 12-week training program. Student’s t-test was used to assess the between-group differences for dependent data to assess the Post-Pre differences. Results indicated that the Physiological variables including Breath holding Time, Maximum Inspiratory, Peak flow rate. Significantly improved in group A compared with the control one. These findings indicate that regular yoga practice can obtain improvements in Physiological vari-ables fitness and may contribute to enhance health status and wellness.

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Battery Less Power Conditioner Using a Super Capacitor[ ]


Providing uninterruptible power to a critical load requires suitable energy storage device preferably an electro chemical battery. But the batteries are a great concern now- a -days since the lead used in most commercial batteries pollute the environment. The capability of providing instant high power, a very long life and very minimum maintenance makes a super-capacitor clearly advantageous than a battery This work proposes to develop a energy friendly ups system using super capacitors as energy storage device. A Matlab simulation model of an online UPS system is presented with the waveforms at various stages. The harmonic content of the super-capacitor based UPS is compared with battery based UPS. Simulation results are presented.

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Power Management in a Renewable Energy Based Hybrid System[ ]


This Work presents a method to operate a grid connected hybrid system. The hybrid system composed of a Photovoltaic (PV) array and a Proton exchange membrane fuel cell (PEMFC) is considered. Two operation modes, the unit-power control (UPC) mode and the feeder-flow control (FFC) mode, can be applied to the hybrid system. The reference value of the hybrid source output must be determined. The variation of hybrid source reference power is eliminated by means of hysteresis. The proposed operating strategy with a flexible operation mode change always operates the PV array at maximum output power and the PEMFC in its high efficiency performance band, thus improving the performance of system operation, enhancing system stability, and decreasing the number of operating mode changes.

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Singular perturbation methods: Application in a hyperelastic compressible cylindrical tube[ ]


This study proposes a mathematical model to investigate stability of arteries. The artery is considered as a prestressed thick-walled tube subjected to dynamical pressure and made of a hyperelastic and composite material. In this context, the purpose of this work focuses on the initial formation of the pathology in human arteries which may be modeled as instability phenomena. For that, a perturbation technique is used on the equations of motion to highlight possible instabilities of the artery. This instability interpretation provides a theoretical approach.

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Geographic- Based Routing Protocol for Heterogeneous Mobile Ad-Hoc Networks[ ]


In infrastructure less network (ILNS), networks might carries with it devices with un-similar characteristics in terms of capacity of the node, antenna and frequency, transmission power and so on. This type of un-similar behavior network, devices are doubtless to transmit at completely different transmission levels, thereby inflicting communication links of frequent break. This may cause link spatial property downside. And also, it attributable to interference raised by high power devices, so networks is going to be severely affected. The related survey of current works, counsel shows that to solely notice the simplex links and to avoid transmissions through such connection. They are not considering the advantages of high-energy devices. This paper highlights strategies to enhance the networking performance of power un-similar ILNs by with efficiency exploiting the benefits and avoiding the disadvantages of high-energy devices.

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Solution Focused Therapy[ ]


This research paper is about solution-focused therapy. In solution-focused therapy, the therapy does not emphasize the problem at all; it stresses and highlights the solution. Solution-focused therapy also considers the client the expert and not the therapist. The client is the expert because no one knows their own lives better than themselves. The therapist is basically there to guide the sessions but the client decides which direction to take. In this paper we go over the history of the theory, types of problems the theory is most useful for, the strengths of the theory, and the weakness of the theory.

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A Stereo Vision-based Guidance System for the Visually Impaired People[ ]


This paper proposes a stereo vision-based algorithm for objects’ depth estimation suggested for guiding visually impaired people. The proposed algorithm is a first step towards a complete system designed for warning visually impaired persons to avoid in front obstacles at a reasonable distance (1m-2m). First, the left and right images are captured by a stereo vision camera. After preprocessing the captured images, objects are detected and segmented using morphological operations then a stereo image rectification is performed. The inliers points differences obtained from epipolar constraint are used to calculate the maximum and the minimum disparity. The suggested algorithm in this paper is tested using images captured for different objects with various distances from the stereo camera. Experimental results show that the proposed algorithm for depth estimation works quite robustly and faster than other methods in the literature.

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ROBOT SOCCER: A REVIEW[ ]


The robot soccer competition is a popular game that offers a set of challenges for intelligent agent researchers using a friendly competition in a dynamic, real-time, multi-agent domain. Soccer is a dynamic game where things change fast and randomly so it cannot be predicted i.e. the robots cannot be pre-programmed. A lot of work has been done in the field of robot soccer to keep the game as close as possible to the real game of soccer. This paper is concentrated on various strategies used in robot soccer.

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PIN-Based scheme for verifying the Physical Entity association[ ]


In software engineering, the term data model is used in two related senses. In the one sense, it is a description of the objects represented by a computer system together with their properties and relationships; these are typically "real world" objects such as products, suppliers, customers, and orders. In the second sense, it means a collection of concepts and rules used in defining data models: for example the model uses relations and tuples, while the network model uses records, sets, and fields. The combination between the data model and process model depicts the business model integration which is the primary goal of the software engineering process. The one common requirement for that data is the confidence in its accuracy and completeness. The social security systems and subsidized services are common practice in many countries, today. The need to a physical identity attached to each beneficiary in such systems is crucial. This will guarantee the delivery of the service to the deserved citizens. Family Card System, FCS, is one of such systems, developed in Egypt, to deliver governmental services to deserved people. To guarantee FCS delivering such services to deserved people, each registered person should be supported by his national number, PIN. FSC itself should be sure that each person not only have a right PIN, but his associated PIN. A big difference between both. In this article, we depict the concepts of data accuracy and how to trust its contents. And association to related person. A scheme for safe entry to the PIN to his related person, signing, and verifying its accuracy and the physical association of the identity to appropriate citizen has proposed.

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Diquark Approach to Calculating the Width of Theta pentaquark state[ ]


Now it is well known that the multiquarks cannot be a simple n-quark states in ground state, because they would freely recombine and decay in baryons and mesons, with a very broad decay width. Lattice QCD (LQCD) determinations of hadrons charge distributions do not support the concept of substantial u - d scalar diquark clustering as an appropriate description of the internal structure of the states, Thus vector diquarks maybe more favourable. In our previous paper we calculated the mass of one interesting multiquark state ( Theta pentaquark, T^+,) by using of vector diquarks. In this paper we use our diquark approach for calculating its decay width using mass calculation results simultaneously. The limit on the T^+ width is very low [20] G_(T )? 1 MeV«G_? for conventional baryon resonances and in quark model this picture is less clear. By using of vector diquark ideas in the chiral limit diquark correlations in the relativistic region and imposing HF interactions between quarks in a vector diquark we have calculated the mass and decay width of Theta pentaquark state simultaneously.

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Obesity of Primary School Children: A Cross-sectional Study in Bangladesh[ ]


The prevalence of obesity and overweight, as a most serious public health problem, has been studied in Bangladesh but not based on a particular city outside of Dhaka. Sylhet, as a developing city, is presumed that it is at risk of holding obese children. So our aim was to uncover the health status of primary school going children of this city and to identify the factors liable to renovate the obesity problem. We collected height, weight and other relevant information from 300 children through a house-based purposive survey. Descriptive analysis and Principal Component Analysis (PCA) have been applied to analyze the data. Among 300 children (aged 5-14 years) we have found 76% are healthy weight, 13.3% overweight, 5.3% underweight and 5.3% obese, where girls have slightly higher obesity rate than boys. Mothers’ occupation, family income, general food intake, computer game and outside-sports are the influential factors of obesity. Although, the level of obesity is not so high, proper steps should be taken to minimize the existing rate through developing both school and family based programs; otherwise the problem could be severe in the future. Taken together, we conclude that the study may help to develop the awareness about the childhood obesity and its associated diseases.

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Effect of Lime-Guinea Corn Husk Ash on the Engineering Properties of Lateritic Soils[ ]


The effect of lime-guinea corn husk (GHA) ash on the engineering properties of lateritic soil was assessed. The lateritic soil, which was modified with guinea corn husk ash and lime as stabilizing agents, was obtained from kudenda along Kaduna-Abuja express way Kaduna (lat. 070, long. 100). The Optimum moisture content (OMC) and Maximum dry density (MDD) of the lateritic soil without stabilizing are 15.24% and 1.73g/cm3 respectively. The sample, on stabilizing with lime-GHA ash, the OMC at 2%, 4%,6%,8%, 10% and 12% of the lime - GHA ash were 15.57%, 15.13%, 18.27%, 18.17%, 21.16% and 21.36% respectively with corresponding MDD of 1.72 g/cm3, 1.74 g/cm3, 1.74 g/cm3, 1.66 g/cm3, 1.62 g/cm3,and 1.61 g/cm3. The OMC at every percentage Lime-GHA were used to cast lateritic bricks and air-dried for 7days, 14days and 21days.The compressive strength of the bricks for 7, 14 and 21days were found to be 0.89N/mm2,0.92N/mm2 and 1.10N/mm2for the control; the compressive strength of the cubes at 7, 14 and 21 days were observed to increased with curing age and reach the optimum strength 8, 10 and 10days respectively (corresponding values of 1.14, 1.21 and 1.35 N/mm2).It is therefore deduced that lateritic soil strength can be improved at 10% each for lime and GHA.

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Social Networks[ ]


Social networking is an Internet based association of a group of people for the purpose of social or business activities. Social networks are established through websites wherein people can associate themselves through registration process and can communicate and share information thereafter. A set of likeminded people can communicate among themselves by forming groups. A social network facilitates new contacts from people around the globe. According to Trampedach, (2014) social network was a powerful mode of communication where individuals can share the information in the form of text, image, voice or video clips. Some of the examples of social networks are facebook, twitter, orkut, vznet, friendster and many others. Along with its multiple benefits, social network also poses certain challenges. The presence of social networks on internet has caused the generation of an enormous amount of information and its unbounded growth with huge number of users has posed a challenging problem. Network engineers are finding ways to manage the user data in an efficient way. With the advance of social networks, users around the world finds themselves connected with the society at all times and can find solution to their problems by discussing the issues with multiple experts all over the world. It has become the effective means for dating, wishing, congratulating, appreciating, passing comments, liking and many more (Boyd, 2014). In this report a detailed analysis has been done on social networking sites and all the pros and cons are discussed in details.

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A review on Emerging trends, Applications and issues of Geospatial Technology in public health in Indian scenario[ ]


Integration of “Information technology”, “GIS” and “GPS” and “Remote sensing” increase the productivity and the quality of Geospatial technology ,so the spatial and non spatial information, data for analysis and decision making by providing, integrated approach and redirect to the disease control and public health and surveillance at local, regional and national levels. Smart planning in terms of emergency public health, care provision and infrastructure protection can be effectively prepared and implemented and Geospatial technology can play a key and vital role in this direction and approach. Various Spatial mapping and samples of different diseases (i.e. vector and water borne diseases) and pollution resources like water distribution lines passing through parallel or cross to the drainage and garbage sites. The availabilities and the accessibilities of health care facilities like the hospitalities, PHC, HP and were located in the GIS environment for further analysis. In this paper we tried out to explore that how Geospatial technology with GIS, GPS and RS is works as a critical tool with several applications disaster related public health issues. And Geographic Information System [GIS] related applications are emerging as powerful technological tools in integrating and analyzing data related to human health in the spatial-temporal context. Further it has also explained the trends, and the applications and the various issues in involves in public health of Geospatial Technology in Indian scenarios. Readability and Reliability of Database, its dependability and accessibility enables the major issues and challenges in India. Creating geo-databases at the micro level in public health departments and the need to relate data on census, demographics, health based, and meteorological, hydrological, environmental, and geographical aspects was emphasized.

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Linked Data Generation with Provenance Tracking: A Review of the State-of-the-Art[ ]


Provenance of data items plays a pivotal role during the reuse and integration of data from the diverse sources. Determination of trust and authenticity is essential to verify various data products available on the web. Over the past few years, data publication in the Linking Open Data (LOD) cloud has been growing rapidly. Due to the absence of meta-data or provenance, data in the web starts suffering from trust and quality. Until now, lot of standard approaches has been proposed for converting legacy data to Linked Data. However, these approaches still lack a reliable method for tracking provenance of the data items. It is imperative to know the existing approaches for better understanding about how the provenance is tracked and stored. This article reviews almost preeminent approaches on tracking provenance during generation of Linked Data from the legacy data systems and presents them concisely by analyzing with various other approaches.

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OPTIMIZATION OF THE ELECTRICAL POWER CONSUMPTION FOR THE DOMESTIC CONSUMERS USING CUTTING-EDGE TECHNOLOGY[ ]


The development in power sector of Bangladesh is relatively slow after liberation war in 1971.The supply of resources is always limited to meet the demand for fast growing population of this country and also the economic and political instability influence the growth of power sector as well. 48.5% people of Bangladesh get the opportunity to use electricity [1].Based on the types and brands of household appliances, the power consumption is different. Most of the household devices are not much energy efficient. The major objective of this project is to survey the electrical power consumption of the domestic consumers and to make comparison of power consumption and efficiency of same sized domestic appliances of different types. Data comparison chart has been made from the collected data. From the chart, proper efficiency, electric bills and monthly bills also calculated. A survey has been conducted in different area of Dhaka city to find out consumer average usage based on income of consumers. Survey data was analyzed to find out the demand of power and percentage of consumer home appliance usage in home. Also, load duration curve has been done to find out total load in home according to the seasonal basis using HOMER. By analyzing the survey results and secondary data, electrical power consumption has been optimized by the most energy efficient home appliance for the domestic users. Besides suggestion of the alternatively improved and energy efficient solution has been given.

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Implementation and Result Analysis of Priority Based Load Balancing In Cloud Computing[ ]


Cloud Computing is not a single terms, it is a combination of two word i.e. cloud and computing. Cloud in cloud computing is the set of hardware, software, network, storage, services, & interfaces that combine to deliver aspects of computing as a service. It has no significance with its name “Cloud”. It generally incorporates infrastructure as a service (IaaS), platform as a service (Pass), and software as a service (SaaS) which are delivered to end users over the Internet. To perform these entire thing load balancing is essential to improve the performance significantly, to provide a tendency of fault tolerance in case the system failures, to maintain the system constancy and to accommodate prospect variation in the system. Load balancing is the mechanism to distribute equal workload and a resource across all the nodes i.e. no single node is over loaded and others remains idle. It guarantees that each and every node has equal load. Now day’s product has been increased rapidly in the cloud computing environment, so we are proposed an algorithm which performs the load balancing on the basis of product priority.

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Review of an Efficient and Optimized Web Mining Technique for Web Log Analysis[ ]


In this paper we reviewed an efficient and optimized algorithm for the web mining for weblog analysis. We are approaching to design a system whose results may applied to the relevant class of issues from search engine, this is to identify the concerned contexts which are directly associated with the securities and marketing of the e-commerce websites it also helpful for the designing of the e-commerce web portals. The concept of the paper is incepted from the Apriori Algorithm and then study various implementation of Apriori algorithm in weblog analysis and page ranking and we compare all the earlier versions of Apriori algorithm. we also study and review the performance of the algorithms implemented for the web mining for weblog analysis and study the time and space complexity with this study we are going to design an technique which can reduce the reduce the data base for the scanning and in result the smaller be the candidate sets in stage wise comparison. We are also trying to make a technique which is much generalized and can be implemented in any type of web log analysis.

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Double Guard: Detecting and Preventing Intrusions In Multi-tier Web Applications[ ]


In today's world we have many issues in internet security and privacy. We use internet in travelling, social media, banking, study etc. But we often face the problems with the privacy of the network system. To accommodate this increase in application and data complexity, web services have moved to a multi-tiered design wherein the web server runs the application front-end logic and data is outsourced to a database or file server. IDS plays a key role in computer security technique. But it also has drawbacks of its own. To overcome those drawbacks Double guard technique is introduced.

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Rechargeable Fan Using a Super Capacitor[ ]


Present day the Indian subcontinent is facing power shortage especially in southern region while the cities getting more share of power, the rural India is suffering from power cuts. To facilitate the production of electricity for basic needs like light and fan, it is prepared to design a rechargeable fan using super capacitor as an energy storage element. This rechargeable fan can be charged from solar panel during the daytime and energy is stored in super capacitor which can work similar to that of a battery. Simulation results are presented in this work.

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Computational Fluid Dynamics Simulation of the dynamics of a tilting disc heart valve prosthesis during the opening and fully open phases[ ]


The study of the hemodynamics is an important component in the design and validation of artificial heart valves. The removal of natural valves and their replacement by artificial valves may considerably alter the physiological flow. This necessitates an extensive verification and validation process involving in-vivo, in-vitro and in-silico models. The pulse duplicator is an in-vitro setup used to validate the performance of the valve dynamics. Physiological pressure and flow waveforms across the valve can be simulated using this setup using lumped impedances representing the systemic resistances and compliances. The use of Computational Fluid Dynamics(CFD) models to simulate the pulse duplicator allows access to parameters like velocity profiles, shear stresses and areas of separation and recirculation which are critical in the design of a heart valve prosthesis. A CFD analysis of the dynamics of a 25 mm sized tilting disc aortic valve was done with geometry and flow waveforms as in the in-vitro pulse duplicator setup. Two phases of the flow were simulated –the opening phase and the fully open phase. The results of the simulation were validated with results from the in-vitro experimental setup.

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The Effect of Indirect Sonication on the Reactivity of Nano Silica Concrete[ ]


The paper studied the effect of changing the duration time of indirect sonication on the reactivity, and dispersion of nano silica as cement substitution for concrete mixes, the optimum duration will then be used to produce nano silica concrete with different substitutions and their compressive strength is to be compared with the -as received- nano silica concrete. The results revealed that optimum nano silica dispersion was found to be reached by applying 5 min of indirect sonication to the nano silica before being added to concrete mix with a gain in compressive strength reached 33% and an increase in the workability as well. Increasing sonication time beyond 7 min resulted in an increase in the re-agglomeration which subsequently affected the compressive strength gain and a significant loss in strength was reported to reach more than -22% for 30 min sonication as compared with the un-sonicated nano silica concrete mix.

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Survey on Particle Swarm Optimization accelerated on GPGPU[ ]


The paper presents an overview of recent research on the Particle Swarm Optimization (PSO) algorithm parallelization on the Graphics Processing Unit for general-purpose computations (GPGPU). This survey attempts to collect, organize, and present reports in the area published since 2007 in a unified way. In order to organize the literature a classification by objective functions and PSO variants is proposed. The paper also compares experimental results taking into account the most popular factor, the calculating acceleration ratio called speedup. Results of the survey are given in a very compact and comprehensive way and could be used as a guide in this area. As a summary, conclusions from categorization, a comparability problem, and possible research areas are discussed.

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The effect of compression rate on hardness for pure Al, Al-5083, and Al-1050 with equal channel angular pressing[ ]


Compared to common metals, with a grain size of tens or hundreds of µm, Ultrafine Grained (UFG) metals, also known as nanocrystalline metals or nonmetals, have their grain size reduced mechanically to about 0.1–1 µm. This structural change affects many mechanical and physical properties of metals. The effect of severe plastic deformation (SPD) during equal-channel angular pressing (ECAP) on grain refinement and strain hardening are studied and was attempted at room temperature to refine grain size of pure Al, Al-5083, and Al-1050. Mechanical properties and the deformation behavior of the ECAP processed material were investigated by the hardness . We can summarize that the increase in velocity (ram speed) on pure Al, Al-5083, and Al-1050 leads to decrease in hardness and an increase in temperature during the ECAP and thus given the opportunity to re-crystallization (geometric dynamic re-crystallization (GDR)) occurs.

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