School of Engineering
URI ถาวรสำหรับชุมชนนี้
เรียกดู
กำลังเรียกดู School of Engineering โดย ชื่อ
ตอนนี้กำลังแสดง1 - 20 ของ 715
ผลลัพธ์ต่อหน้า
ตัวเลือกเรียงลำดับ
รายการ Alkali-Activated Masonry Units Using Crushed Cellular Lightweight Concrete to Fully Replace Cement and Natural Sand(2566-04) วริสรา เลิศไพฑูรย์พันธ์; สุรพันธ์ สันติยานนท์คอนกรีตบล็อกมวลเบาแบบเติมฟองอากาศ (CLC) ที่แตกหักเสียหายจากการผลิต การขนย้าย รวมทั้งเศษเหลือจากการตัด เป็นขยะที่จะต้องขนทิ้ง ซึ่งเสียค่าใช้จ่ายและเป็นภาระต่อพื้นที่ฝังกลบ การผลิต CLC ก็ต้องใช้ซีเมนต์และทรายที่เป็นทรัพยากรธรรมชาติที่ใช้แล้วหมด หากสามารถนาเศษ CLC กลับมาใช้ใหม่เพื่อเป็นวัสดุก่อสร้างก็จะเป็นผลดีต่อสิ่งแวดล้อมและตอบสนองต่อโมเดลเศรษฐกิจบีซีจี (BCG Economy) งานวิจัยนี้จึงนาเศษ CLC ที่บดละเอียด ผสมกับสารกระตุ้น (Activating Solution) คือโซเดียมไฮดรอกไซด์และโซเดียมซิลิเกต เพื่อพัฒนาเป็นวัสดุเบาก่อผนังแทน CLC ชนิด C16 ที่ต้องมีค่ากาลังต้านแรงอัดไม่น้อยกว่า 51 กิโลกรัมต่อตารางเซนติเมตร โดยใช้ความเข้มข้นของโซเดียมไฮดรอกไซด์ 5 และ 7.5 โมลาร์ และมีอัตราส่วนของ เศษ CLC: สารกระตุ้น เป็น 1: 1.5 ผลการวิจัยพบว่า ก้อนตัวอย่าง มีค่าความต้านแรงอัดสูงสุด (ที่ 28 วัน) เท่ากับ 115 และ 99 กิโลกรัมต่อตารางเซนติเมตร สาหรับส่วนผสมที่ใช้ความเข้มข้นโซเดียมไฮดรอกไซด์ เท่ากับ 5 และ 7.5 โมลาร์ ตามลาดับ และมีความหนาแน่นอยู่ระหว่าง 1,600-1,650 กิโลกรัมต่อลูกบาศก์เมตร ทุกระยะเวลาการบ่มรายการ All EE Papers(2554-02-18) Ajarn EEรายการ All ME Papers(SPU Knowledge Bank, 2554-02-18) Ajarn MEรายการ Application of Distributed Slack Bus Power Flow to Competitive Environments(Proceeding of the Australasian University Power Engineering Conference 2007, 2550-12-09) Keerati ChayakulkheereeThis paper presents the mathematical model of distributed slack bus power flow (DSPF) program and its application to competitive electricity supply industry (ESI). The advantage of DSPF is its ability to compute the frequency deviation when the ACE is treated as fixed value. It can represent the automatic generation controls (AGC) for maintaining nominal frequency. More specifically, the proposed method can diversify the power imbalance to voltage controlled buses in the system via participation factor. Therefore, the AGC of the generators can be incorporated in the analysis. The participation factors of the generators are obtained by the weighted average of AGC accepted quantities in ancillary services market. The results shows that the proposed method can satisfactory represent the system behaviour that all generators are response to power imbalance. In addition, the proposed method results in the better justified AGC setting in competitive electricity market than that of using single slack bus power flow. The DSPF is tested with the IEEE 30 bus system and compared to single slack bus power flow solution. Numerical results shown that the method can effectively represent the generation control characteristics to the power flow model and potentially be applied to simulate the competitive electricity markets.รายการ Application of Distributed Slack Bus Power Flow to Competitive Environments(2555-08-05T07:32:46Z) Keerati ChayakulkheereeThis paper presents the mathematical model of distributed slack bus power flow (DSPF) program and its application to competitive electricity supply industry (ESI). The advantage of DSPF is its ability to compute the frequency deviation when the ACE is treated as fixed value. It can represent the automatic generation controls (AGC) for maintaining nominal frequency. More specifically, the proposed method can diversify the power imbalance to voltage controlled buses in the system via participation factor. Therefore, the AGC of the generators can be incorporated in the analysis. The participation factors of the generators are obtained by the weighted average of AGC accepted quantities in ancillary services market. The results shows that the proposed method can satisfactory represent the system behaviour that all generators are response to power imbalance. In addition, the proposed method results in the better justified AGC setting in competitive electricity market than that of using single slack bus power flow. The DSPF is tested with the IEEE 30 bus system and compared to single slack bus power flow solution. Numerical results shown that the method can effectively represent the generation control characteristics to the power flow model and potentially be applied to simulate the competitive electricity markets.รายการ Avalanche Gain and Shot Noise in Silicon-based Planar MSM Structures(The 41st Electrical Engineering Conference (EECON-41), 2561-11-21) Sanya Khunkhao; Aphichata Thongrak; Korn Puangnak; Wanchai ChankaipolThe properties of planar metal-semiconductor-metal (MSM) optical sensor structures on dc photocurrent gain have been investigated an experimentally. The structure has two co-planar Mo/n-Si Schottky-barrier junctions on silicon of resistivity 9-12 Ω-cm and the electrode separation is 2000 µm. The current-voltage (I-V) characteristics measurements under illumination in visible range showed a rapid increase in photocurrent at higher biases examined. The dependence of I-V characteristics and noise measurements, such photocurrent increased was ascribed to avalanche multiplication of carriers photogenerated in the Schottsky junction as applied reverse-biased. From low-frequency (10-50 kHz) signal measurements, it was found that multiplication factor larger than 100 at 10 kHz and 30 at 50 kHz was achieved.รายการ BIM IFC - FM services in HVAC operations(2564-11-17) เด่นชัย วรเดชจำเริญรายการ BIM utilization for the operation and renovation enhancement of chiller plant manager system performance(2565-11-04) Denchai Woradechjumroen; Somkiat Sohab-รายการ Contingency Estimation based on Risk Events of Tunnel Construction : Case study Nam Thuen 1 Hydropower Project(RSU International Research Conference 2019, 2562-04-26) Paijit Pawan and Thammasak RujirayanyongThis study aimed to integrate risk event occurred in tunnel construction and calculate contingencyรายการ Development of Lightweight Concrete Interlocking Block Panel with Water Treatment Sludge and Expanded Metal Ferrocement(Engineering Journal, 2564-01-31) Rattawit Amornpunyapat; Phaiboon Panyakapo; Mallika PanyakapoAn innovative lightweight concrete interlocking block panel was developed to improve the lateral resistance of the infilled frame with green construction material. The water treatment sludge obtained from Bang Khen water treatment plants was employed to replace the fine aggregate. The lightweight concrete interlocking block panel was strengthened with ferrocement technique and expanded metal sheet. Three sets of the strengthened block panels with various sizes of expanded mental were investigated: concrete block panel, interlocking block panel with thin bed adhesive mortar, interlocking block panel with thick bed cement mortar. The concrete with mixed proportion of cement, sand, water, foaming agent, and sludge of 1:0.70:0.60:0.006:0.30 by weight was suitable for producing the lightweight concrete block according to the Thai Industrial Standard. The compressive strength test of masonry prisms and the diagonal tension (shear) test were conducted for the three sets of the strengthened block panels. The test results reveal that the interlocking block was superior to the conventional concrete block in terms of strength and ductility capacity due to the effect of interlocking between the block. The shear key with thick bed cement mortar is more effective than the thin bed adhesive mortar typically used in the construction of lightweight concrete.รายการ Distributed Slack Bus Power Flow Part I: Mathematical Model and Framework(The 30th Electrical Engineering Conference, 2550-10-25) Keerati ChayakulkheereeThis paper presents the mathematical model and test example of distributed slack bus power flow (DSPF) program. The method can diversify the power imbalance to voltage controlled buses in the system via participation factor. Therefore, the automatic generation controls (AGC) of the generators can be incorporated in this power flow model. The DSPF is tested with the IEEE 30 bus system. Numerical results shown that the method can effectively represent the generation control characteristics to the power flow model and potentially be applied to the overcoming competitive electricity supply industry.รายการ Distributed Slack Bus Power Flow Part II: Prospect and Challenge for Competitive Environments(The 30th Electrical Engineering Conference, 2550-10-25) Keerati ChayakulkheereeThis paper introduces an application of distributed slack bus power flow to competitive electricity supply industry (ESI). The participation factors of the generators are obtained by the weighted average of AGC accepted quantities in the ancillary services market. The results shows that the proposed method can satisfactory represent the system behavior that all generators are response to power imbalance. In addition, the proposed method results in the better justified AGC setting in competitive electricity market than that of using single slack bus power flow.รายการ Economic of Power System Reliability [Presentation](2551-02-24T04:30:40Z) Keerati Chayakulkheereeรายการ Energy storage for enabling integration of power system(2561-09) Pachern Jansaรายการ The Enhanced System Performance of Solar Cells by Diffused Reflection(International Symposium on Engineering and Natural Sciences, 2558-08) Apirak Sawatkit; Varunyou BunyaopasThis study aims to investigate efficiency enhancement of solar cells by using the mirror reflector to increase the intensity of sunlight. In conducting the study, 2 sets of 40-watt solar cells with the dimension of 470 mm. width x 676 mm. length x 2 mm. thickness, and a mirror reflector which was 235 mm. wide and 676 mm. long were used. The reflector was tilted at 67 degrees horizontal to one solar cell and the cell was faced southward at 14 degrees horizontal, the perfect angle for maximum sun exposure in the area of Pachee district, PhraNakhon Si Ayutthaya province, where the study was carried out. During the experiment, temperature, electricity current, voltage, and sunlight intensity were observed and recorded. The data was collected between April 9-15, 2014, from 6 a.m. to 6 p.m., the period when sunlight intensity reached the maximum point. Generally, the sky was clear and the temperature was high during that period, so it was expected that the efficiency of solar cells would drop. However, the study found that the solar cell with more focused sunlight due to the mirror reflector produced the power at the rate of 17.02% on the day when the temperature of the solar cell was 67.4 degrees Celsius. The data suggested the likeliness of higher efficiency and the average rate of 27.13% increase in energy output of the solar cell, compared to the typical efficiency of solar cells when no mirror reflectors were used.รายการ The Enhanced System Performance of Solar Cells by Diffused Reflection(International Symposium on Engineering and Natural Sciences, 2558-08) Apirak SawatkitThis study aims to investigate efficiency enhancement of solar cells by using the mirror reflector to increase the intensity of sunlight. In conducting the study, 2 sets of 40-watt solar cells with the dimension of 470 mm. width x 676 mm. length x 2 mm. thickness, and a mirror reflector which was 235 mm. wide and 676 mm. long were used. The reflector was tilted at 67 degrees horizontal to one solar cell and the cell was faced southward at 14 degrees horizontal, the perfect angle for maximum sun exposure in the area of Pachee district, PhraNakhon Si Ayutthaya province, where the study was carried out. During the experiment, temperature, electricity current, voltage, and sunlight intensity were observed and recorded. The data was collected between April 9-15, 2014, from 6 a.m. to 6 p.m., the period when sunlight intensity reached the maximum point. Generally, the sky was clear and the temperature was high during that period, so it was expected that the efficiency of solar cells would drop. However, the study found that the solar cell with more focused sunlight due to the mirror reflector produced the power at the rate of 17.02% on the day when the temperature of the solar cell was 67.4 degrees Celsius. The data suggested the likeliness of higher efficiency and the average rate of 27.13% increase in energy output of the solar cell, compared to the typical efficiency of solar cells when no mirror reflectors were used.รายการ The Enhanced System Performance of Solar Cells by Diffused Reflection(International Symposium on Engineering and Natural Sciences, 2558-08) Apirak Sawatkit; Varunyou BunyaopasThis study aims to investigate efficiency enhancement of solar cells by using the mirror reflector to increase the intensity of sunlight. In conducting the study, 2 sets of 40-watt solar cells with the dimension of 470 mm. width x 676 mm. length x 2 mm. thickness, and a mirror reflector which was 235 mm. wide and 676 mm. long were used. The reflector was tilted at 67 degrees horizontal to one solar cell and the cell was faced southward at 14 degrees horizontal, the perfect angle for maximum sun exposure in the area of Pachee district, PhraNakhon Si Ayutthaya province, where the study was carried out. During the experiment, temperature, electricity current, voltage, and sunlight intensity were observed and recorded. The data was collected between April 9-15, 2014, from 6 a.m. to 6 p.m., the period when sunlight intensity reached the maximum point. Generally, the sky was clear and the temperature was high during that period, so it was expected that the efficiency of solar cells would drop. However, the study found that the solar cell with more focused sunlight due to the mirror reflector produced the power at the rate of 17.02% on the day when the temperature of the solar cell was 67.4 degrees Celsius. The data suggested the likeliness of higher efficiency and the average rate of 27.13% increase in energy output of the solar cell, compared to the typical efficiency of solar cells when no mirror reflectors were used.รายการ EV wireless charging towards industrial adaptation(Advance Industry Media Plus Co., Ltd, 2563-11) Pachern Jansa-รายการ Evaluation of CPMS installation and performance for energy savings(Department of Mechanical Engineering, Faculty of Engineering, King Mongkut’s University of Technology Thonburi (KMUTT), 2565-12-13) Denchai Woradechjumroen; ์Nontawat MoonsriA large building or a factory with an open office area is commonly used for a centralized chiller plant system (CPS), including a chiller, chilled water pump, condensing pump, and cooling tower. A centralized control system called chiller plant management system (CPMS) has been installed to reduce complex operations and allow the system to operate according to the settings for appropriate working time. Even though there is an installation guide from developing countries, installing hardware and software in Thailand still lacks clear standards or guidelines. As a result, the communication speed between the control system and the device is inappropriate. It leads to restrictions on data transmission and difficulty assessing performance with appropriate data. As a guideline for future development, this research proposes development for evaluating hardware, software and CPMS performance (characteristic quantity (CQ) and heat balance). It is divided into hardware checks according to aggregate communication and sub-communication to obtain adequate data for the system performance evaluation. The guidelines have been developed by recommended equipment manufacturers widely used in Thailand. It is used in three large-scale commercial buildings. It was found that the communication device supports data transmission every 15 minutes, there is no communication signal interruption, and the software system is suitable for recording CPS data to support: (1) energy-saving assessment and (2) process of ecU9zzVtYvaluating the performance of the CPS system in terms of CQ analysis and heat balance theory. The finding process can be used to evaluate exiting CPMS performance before the improvement.รายการ Fault detection involving unfavorable interaction effects to enhance the fault diagnostics of refrigeration systems in commercial supermarkets(Springer Verlag, 2564-04-15) Denchai woradechjumroen; Thananchai LeephakpreedaMost HVAC&R machine issues are inherently caused by problems in routine operations, decommissioning problems, improper design, and poor installation, and these issues can result in excessive energy consumption and a short equipment lifespan. Existing fault detection and diagnosis (FDD) methods for refrigeration systems have been considered in supermarket environments. However, typical HVAC systems are generally operated without considering indoor conditions as the drivers of refrigeration operations. This issue leads to unreliable refrigeration data for FDD design. This article systematically proposes a novel fault detection method for faulty HVAC operations related to problems in routine operations and the excessive energy use of refrigeration systems. Four steps are developed as a novel unfavorable interaction strategy to identify abnormal HVAC operations based on identified energy signatures. Outdoor and zonal air temperatures (OAT and ZAT) are concurrently utilized to specify typical area operations for rooftop units (RTUs). A fault detection approach is proposed based on RTU outliers using plots of OAT and ZAT versus the energy consumption of the refrigeration system based on fixed 10% differences in the indoor relative humidity range. The findings of a case study involving five supermarkets demonstrate the potential to identify the outliers that cause unsuitable dead-band zones and temperature set points for RTU operations, which can lead to excessive energy consumption of refrigeration units. The proposed methodology enhances the data reliability and robustness of FDD for refrigeration systems.
