จำนวน Repository ( 255 )
การศึกษาผลกระทบทางเศรษฐศาสตร์สำหรับระบบจำหน่ายไฟฟ้าที่มีเครื่องกำเนิดไฟฟ้าแบบกระจายตัว
A distributed generation is a small-scale Installed in the customer density sources. The benefits of distributed energy resources is one example. To improve the reliability of power distribution system for the better. The increased reliability of power distribution system that is connected to the source of power distribution efficiency depends on the size of the supply and installation of power distribution are considered appropriate. To Evaluation the reliability in distribution system with the main purpose is to the minimization for customer interruption cost. The technique employed to minimization problem for customer interruption cost in solved by the developed tabu search algorithm together with reliability worth analysis that provide an indirect measure for cost implication associated with power failure. The developed methodology is tested with a distribution system of Roy Billinton Test System (RBTS) bus 2. Numerical results from the tests demonstrate that distributed generation can be used to promote economy and reliability of the distribution systems.
การประเมินสมรรถนะการป้องกันฟ้าผ่าในระบบส่งกําลังไฟฟ้า
This Research purposes assessment of lightning performance on transmission system 69 kV in Metropolitan Electricity Authority (MEA). The case studies illustrated the lightning strike to direct top pole in order to guideline considering the critical flashover voltage value of insulator is able to withstand it and improvement lighting protection in the future. This solution analyzes using the Alternative Transient Program-Electromagnetic Transient Program (ATP-EMTP). The result found that voltage across insulator before and after improvement lightning protection by external ground wire. Factor effect to voltage across the insulators is the tower footing resistance wave of lightning current and interval between towers. It depends on relation with front time of wave. The analysis economics is very important. This Research is studying interruption cost of outage since back flashover so analysis the break even point of the installation external ground. The result found upon improvement lightning protection by installed external ground. The pay back period of that is 9 years installed ago. This result can conclusion is external ground able reduction interruption costs of outage.
Design of the printed loop antenna for HF-RFID system
In this paper the printed loop antenna is proposed for high frequency radio frequency identification (HF-RFID) systems (13.56 MHz). The proposed antenna is designed on the printed circuit board (PCB). The antenna structure consists of printed semi-spiral loop with rectangular structure patch at the middle of loop. It can provide the magnetic field distribution to cover the operating area with various directions that can improve the communication performance between reader and various tag orientations. From the measured results the proposed antenna has more efficient than the printed spiral loop antenna
การวิจัยและพัฒนาการหล่ออลูมิเนียมเพื่อผลิตตัวเรือนเครื่องประดับด้วยการหล่อระบบเหวี่ยง
This paper describes an aluminum casting jewelry manufacturing because of the current manufacturing costs are higher. Material or metal that is commonly used to cast jewelry is silver which aluminum Alternatives to metal. Melting is There is a close color and surface finish can be beautiful. But aluminum is a material that is cheap has studied and tested. Replacement aluminum casting body jewelry. The temperature in the baking mold before casting to test all five temperatures are 550 500 450 400 350 degrees Celsius then casting body jewelry in the next stage of the research process casting jewelry with the. aluminum to Experimental temperatures used in baking mold casting plaster for the mold temperature of 400 is appropriate. Best of casting jewelry with aluminum. The results showed that there is minimal waste and a 102 pieces of 48 pieces and has a smooth surface. A similar performance to the other materials available. Similar properties
The Development of multimedia and interactive system, through network for learning of opportunities school
This research focuses on development of Multimedia and Interactive System through Network for Learning of Opportunities School. This system used as a channel for students to learn outside the classroom and used as a teaching management tool for teacher. Tools for system development were program Microsoft Visual Studio. Database management system with MySQL. Write commands to work with PHP and Java scripts. For evaluating efficiency of the developed system this research used Sample group to answer questionnaires. The population of research is teachers and students of the Bankamwa school (Weboonratsamakee) in totals 97 people. The result of experiment shows that group is recognized the performance of system in the higher level and the system has efficiency of working.