จำนวน Repository ( 2131 )
การหาค่าพารามิเตอร์ของตัวควบคุมแบบสัดส่วนบวกอินทิกรัลแบบ อัตโนมัติด้วยขั้นตอนวิธีเชิงพันธุกรรมสำหรับระบบการขับเคลื่อนมอเตอร์ซิงโครนัสชนิดแม่เหล็กถาวร
Proportional plus integral controller has been widely used in permanent magnet synchronous motor (PMSM) drive system due to its simple structure while achieving zero steady-state error. However finding out the optimal parameters of the controller is not an easy task. For this reason this paper presents an automated optimization of proportional plus integral controller for permanent magnet synchronous motor drive system using genetic algorithms. Simulation and experimental results verify the effectiveness than ones of the trial and error method.
การลดของเสียในกระบวนการผลิตชิ้นงานความเที่ยงตรงสูงโดยใช้หลักแนวคิดของลีน กรณีศึกษา : บริษัท อาร์แอนด์ดี พรีซิชั่น จำกัด
R & D PRECISION CO.LTD manufactures various types of work. Yet there were defects of work in previous working and the company was unable to deliver products to customers as required and some might have been destroyed. As the information referred to the waste detected each month from January 2014 to June 2014 it is found that the volume of defect rate was 9.56 percent resulting in losing cost of production and other business opportunities. This research aims to reduce waste in the production of high precision with lean concepts. The study starts from the analysis of employees working information by creating a value stream mapping. The study found that cylindrical grinding takes the longest time. Then the study explored and determined the root cause of the problem by using a Pareto Diagram together with a Fish-Bone Diagram to analyze the minor causes. It is found that most wastes are caused by measuring control especially for the work that has a shaft hole with thickness of 2.25 mm. Thus the study and experiment were conducted to determine the flow rate of the coolant for the work piece in the cylindrical grinding machine and a fixed value is the rate of decreasing the size of work speed of stone wheel and work type of coolant and type of grinding stones. The goal is to reduce waste by not less than five percent and to improve the process of reducing waste effectively which will affect the environment having lesser wastes from production. It also supports competitiveness and rapid change of industry manufacturing highprecision parts in the future even better.
กระบวนการสนับสนุนการตัดสินใจในการปรับปรุงประสิทธิภาพกระบวนการผลิตน้ำดื่มด้วยการประยุกต์ใช้เทคนิคการรีโทรฟิตและกระบวนการวิเคราะห์เชิงล้าดับชั้น
The objective of this research was presented a decision support making process for efficiency improvement of drinking water processing using retrofit technique for machine and equipment rehabilitate. This methodology was applied Analytic Hierarchy Process (AHP) for selecting an appropriate maintenance sub-contractor. To complete the research existing water purifying machine and tools were inspected to assess its capacity. Future capacity of the purifying machine was also identified. Consequently machine and tools such as water tank and water filter were inspected for retrofitting for the example water tank water filter water quality control and bottle packing. Finally the analytic hierarchy process was utilized to select the most appropriate maintenance sub-contractor. In this process both qualitative and quantitative processes were analysed. The result of this research has been found that this multicriteria decision making process could be used to support the decision making investment process of water purification retrofit unit at Faculty of Engineering Rajamangala University of Technology Phra Nakorn efficiently. Furthermore it could be reduced bias from decision makers while the decision was accepted by all stakeholders.
การประยุกต์เทคนิคการควบคุมกระบวนการทางสถิติในการตรวจติดตามการปล่อยก๊าซคาร์บอนไดออกไซด์จากการเดินทางโดยรถไฟฟ้าบีทีเอส
CO2 emission of rail transportation system plays more important role including the expansion of BTS route that consume the energy and emit CO2 gas more and more. The purpose of this research was to find out amount of CO2 emission from travelling by BTS train and determine specific CO2 emission per product in the form of gCO2e/passenger/km then forecasting on CO2 emission from BTS operations. Research process was initiated from collecting monthly data on ridership distance and electricity for 55 months continuously then regression analysis CUSUM and time series analysis were used for prediction and analysis of CO2 emission. The finding indicated that BTS’s specific CO2 emission was 24.7 gCO2e/passenger/km. Forecasting CO2 Emission from BTS result that Winters Exponential Smoothing Method is most accuracy then Double Exponential Smoothing Method Trend Analysis Method and Decomposition Method respectively. The result of these analysis could be used to calculate carbon footprint from staff travelling by BTS train and promote people to use public transport by government as sustainable transportation concept.
การเลือกใช้โซล่าเซลล์ที่มีประสิทธิภาพให้เหมาะสมกับการใช้งานใน ภูมิประเทศเขตร้อนชื้น
Now is a great time to be an entrepreneur as there are many solar business opportunities to develop. The market for solar products is growing quickly over last year so now this market is helping people get the most from the sun. The market and can be a great source of ideas for usage in the home and with your business. To measure efficiency of the solar energy in Thailand we have installed and tested the solar cell to detect and record the voltage electric current electric power temperature on the solar cell outdoors and check factors related to efficiency of the solar cell when high temperature and efficiency of the solar cell in various weather conditions. The following is the summary of average Wattage and used the Cumulative Sum Control Chart techniques. The Resulting research shows the direct current electric supply below: Solar cell “A” current distribute 85.78 W Solar cell “B” current distribute 81.19 W Solar cell “C” current distribute 95.65 W The temperature on the solar cell can be seen below: Solar cell “A” is 53.88 °C Solar cell “B” is 53.68 °C Solar cell “C” is 52.79 °C Summary of result is the solar cell “C” has highest electric power and the least temperature and this solar cell “C” suitable for use in Thailand. This research results is only relevant when deciding which solar cell to select