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A Novel Handoff Necessity Estimation Approach Based on Travelling Distance
No full textMobility management is one of the most important challenges in Next Generation Wireless Networks (NGWNs) as it enables users to move across geographic boundaries of wireless networks. Nowadays, mobile communications have heterogeneous wireless networks offering variable coverage and Quality of Service (QoS). The availability of alternatives generates a problem of occurrence of unnecessary handoff that results in wastage of network resources. To avoid this, an efficient algorithm needs to be developed to minimize the unnecessary handoffs. Conventionally, whenever Wireless Local Area Network (WLAN) connectivity is available, the mobile node switch from cellular network to wireless local area network to gain maximum use of high bandwidth and low cost of wireless local area network as much as possible. But to maintain call quality and minimum number of call failure, a considerable proportion of these handovers should be determined. Our algorithm makes the handoff to wireless local area network only when the Predicted Received Signal Strength (PRSS) falls below a threshold value and travelling distance inside the wireless local area network is larger than a threshold distance.Through MATLAB simulation, we show that our algorithm is able to improve handover performance
The Effectiveness of Science Textbook Based on Science Technology Society for Elementary School Level
No full textThis study reports a quasi-experimental investigating the development of Science textbook based on Science Technology and Society for elementary school. The data collection was got from the achievement test (pretest-posttest). The population was all fourth-grade students of elementary schools in Gatak Subdistrict and the sample of the study was two schools as an experimental class and control class. The research sample was taken by random sampling technique. The results of this research showed that there was an improvement of student achievement before and after the implementation of science textbook based on Science Technology and Society. The result of the independent sample t-test shows that tobs is higher than table (5.489>1.681). The outcomes of the learning improvement in the experimental class based on the acquisition of N-Gain scores of 0.558. Based on tobs results, H0 is rejected. So it can be concluded that the development of a science textbook based on Science Technology Society in elementary school is appropriate to use for learning
An Assessment of Project Teacher Exchange for ASEAN Teachers (TEACH) Program
No full textAssociation of Southeast Asian Nations (ASEAN) integration aims to unite the South East Asian countries to promote better opportunities for the member countries in different areas such as economics and education. As a response, Philippine Normal University spearheaded the formation of the Association of Southeast Asian Teacher Education Network to promote collaboration with ASEAN countries and enhance teacher education programs. The formation of AsTEN creates the impetus to explore possibilities for the internationalization of teacher education programs among the ASEAN countries. Thus, the Institute of Teaching and Learning of PNU initiated the Project Teacher Exchange for ASEAN Teachers (TEACH). This paper reports the assessment of the piloting of the Project TEACH as experienced by the Thai participants. Moreover, this research aims to develop a model that can be utilized by other ASEAN communities as they prepare for their own international teacher education programs
Elementary School Third Grade Students’ Expectations of Their Teachers in The Course of Language Education
No full textThe purpose of the study is to determine the elementary school third grade students’ expectations of their classroom teachers within the context of the course of language education. The sampling of the study is comprised of 200 elementary school third grade students attending elementary schools in the Milas Province of the city of Muğla. The data were gathered by means of the questionnaire, which had six sub-categories, in order to identify students’ expectations of their teachers. The findings of the study revealed that the students have high expectations of their teachers in terms of the sub-dimensions of active participation, verbal participation, written participation, participating in reading, inclusion of the topics and measurement and evaluation. The students’ expectations of their teachers in relation to the sub-dimension of measurement and evaluation were found to be varying significantly depending on the gender variable. This difference is in favor of boys
Recognition of Metal Objects inside Wall using Antipodal Vivaldi Antenna
No full textThis paper present a recognition technique of metal placed inside and between two walls. A unique scheme of recognition of metallic objects through Ultra Wide Band (UWB) Modified Antipodal Vivaldi Antenna (MAVA) frequency range of (3.1GHz to 10.6 GHz) is presented in this paper.The working mechanism of detection system based on Time Domain Reflectrometry (TDR) using through wall imaging (TWMI). A very small duration pulses generated by Vector Network Analyzer (VNA) which are used for illuminate the wall.The analysis of a system under UWB antenna probe array. The simulation results of MAVA have given an enormous potential of penetration, in order to recognize concealed metal objects with fine precision, proving a smart development in the detection system technology. The improvement of resolution in an image, special filters have been developed and implemented. The design and optimization progression is conceded out via CST simulation software for parametric performance assessment of return loss, radiation pattern and directivity
RF Energy Harvesting with Multiple Sources in Wireless Mesh Network
No full textEnergy harvesting (EH) module for wireless sensor network has become a promising feature to prolong the conventional battery inside the devices. This emerging technology is gaining interest from sensor manufacturers as well as academicians across the globe. The concept of employing EH module must be cost effective and practical. In such, the use of EH module type besides RF is more realistic due to the size of the scavenger module, the availability of the resources and conversion efficiency. Most of the oil and gas plants have some drawbacks in scavenging RF from surrounding (i.e. router, Wi-Fi, base station, cell phone) due to its placement in remote area and thus limited energy sources could be a threat in this application. Multiple sources, including co-channel interference (CCI) in any constraint nodes is a feasible way of scavenging several wastes from ambient RF energy via wireless mesh topology. In this paper, a 3-node decode-and-forward (DF) model is proposed where the relay node is subject to an energy constraint. Multiple primary sources and CCI are added in the system model known as Multiple-Source and Single-Relay (MSSR). A mathematical model is derived in Time Switching Relaying (TSR) and Power Splitting Relaying (PSR) schemes to obtain an average system throughput at a destination. Numerical simulation with respect to the average throughput and EH ratio was performed and compared with the Single-Source and Single-Relay (SSSR) and ideal receiver. By applying multiple sources and CCI as an energy enhancement at the constraint node, the optimal value of EH ratio for TSR can be reduced significantly by 10% as compared to the ideal receiver whereas the optimal value of EH ratio for PSR is outweigh TSR in terms of overall system throughput
A Study of Some Iterative Methods for Solving Fuzzy Volterra-Fredholm Integral Equations
No full textA fuzzy Volterra-Fredholm integro-differential equation (FVFIDE) in a parametric case is converted to its related crisp case. We use homotopy analysis method to find the approximate solution of this system and hence obtain an approximation for the fuzzy solution of the FVFIDE. This paper discusses existence and uniqueness results and convergence of the proposed method
Harmonic Load Diagnostic Techniques and Methodologies: A Review
No full textThis paper will review on the existing techniques and methodologies of harmonic load diagnostic system. The increasingly amount of harmonic producing load used in power system are the main contribution in quantifying each harmonic disturbance effects of the multiple harmonic producing loads and it became very important. Literature proposes two different techniques and methods on the harmonic source identification under the soft computing technique classification. The advantages and disadvantages of harmonic load identification techniques and methods are discussed in this paper. In the proposed method, the issue on the harmonic contribution is determine and transformed to a data correlation analysis. Several techniques to identify the sources of harmonic signals in electric power systems are described and reviewed based on previous paper. Comparative studies of the methods are also done to evaluate the performance of each techniques. However, without sufficient information in this inconsistent environment on the property of the power system, accurate harmonic producing load diagnosis methods are important and further investigations in this regard assumes great implication
Evaluation of Power Minimization for Routing Protocol and Multicast Networks
No full textIn this paper explore the scenario of wireless multicast with a single source and multiple relay that together convey consecutively refined sources to multiple receiver. Joint source-channel coding (JSCC) protocol is proposed aimed at mitigating the complexity and difficulty in signal synchronization in multicast taking end-to-end mean cube error deformation as the quality of service measure the problems of JSCC communication are formulated to minimize the total power utilization where both relay selection and power allocation at the base station (BS) and all the relays are jointly determined to solve the formulated problem that is nonetheless nonlinear in nature a two-step iterative algorithm is investigated for power allocations at all transmitters where a in order quadratic programming method is developed into find a strict local minimum. To reduce the computation complexity a heuristic algorithm for relay selection is presented. Case studies are conducted to verify the proposed formulations and solution methods
Relay Based Performance Metrics of Bluetooth Scatternet Scheduling
No full textBluetooth is an emerging mobile ad-hoc network that accredits wireless communication to connect various short range devices. A single hop network called piconet is the basic communication topology of bluetooth which allows only eight active devices for communication among them seven are active slaves controlled by one master. Multiple piconets are interconnected through a common node, known as Relay, to form a massive network called as Scatternet. It is obvious that the performance of Scatternet scheduling is highly dependent and directly proportionate with the performance of the Relay node. In contrary, by reducing the number of Relays, it may lead to poor performance, since every Relay has to perform and support several piconet connections. The primary focus of this study is to observe the performance metrics that affects the inter-piconet scheduling since the Relay node’s role is like switch between multiple piconets. In this paper, we address and analyze the performance issues to be taken into consideration for efficient data flow in Scatternet based on Relay node