EGI-01. บทความวิชาการ/วิจัย (วารสารระดับนานาชาติ)
URI ถาวรสำหรับคอลเล็กชันนี้
เรียกดู
การส่งล่าสุด
รายการ A Study on the System Imbalance of the Single-Switch Converter for the Conductive Common Mode Noise Reduction(2555-08-05T04:58:32Z) Boonpirom NimitThis paper reduces system imbalance by replacing the single-switch converter with a synchronized double-switch converter based on two active switches technique and hybrid balance technique, including active balance and passive balance for common mode noise reduction. The system balance is experimentally evaluated by the common mode rejection ratio (CMRR). Finally, examples show that the CMRR of the single-switch converter is improved from 1.67 dB to 32.04 dB when the double-converter with two active switches technique is applied and to 41.5 dB when the double-switch converter with hybrid balance technique is applied.รายการ Optimal Power Flow Considering Non-Linear Fuzzy Network and Generator Ramprate Constrained(2555-08-05T04:54:16Z) Keerati ChayakulkheereeThis paper proposes a fuzzy constrained optimal power flow (FCOPF) algorithm with non-linear fuzzy network and generator ramprate limit constraints. The problem is decomposed into total fuel cost fuzzy minimization subproblem and total real power loss fuzzy minimization subproblem, which are solved by fuzzy linear programming (FLP). In the total fuel cost fuzzy minimization subproblem, the line flow and transformer loading limits and the generator ramprate limits are treated as fuzzy constraints. Whereas, in the total real power loss fuzzy minimization subproblem, the bus voltage magnitude limits are treated as fuzzy constraints. The non-linear S-shape membership function is used for representing soft characteristic of fuzzy constraints. The proposed FCOPF algorithm is tested on the IEEE 30 bus test system with and without lines outage cases. The results show that the fuzzy constrained optimal power flow algorithm can successfully trade off among total fuel cost, line flow and transformer loading and generator ramprate in the total fuel cost fuzzy minimization subproblem and between total real power loss and bus voltage magnitude in the total real power loss fuzzy minimization subproblem.รายการ Seismic Analysis of RC Frames with Brick Infill Panel Strengthened by Steel Cage and Expanded Metal(Engineering Journal, 2564-04-30) Phaiboon PanyakapoThe seismic analysis of reinforced concrete infilled frame strengthened by using steel cage and expanded metal was investigated. The strengthening technique of steel cage consisted of steel angle, batten and expanded metal sheet was employed. The brick infill panel was strengthened with ferrocement and expanded metal. The flexible base foundation was considered by modelling the pile foundation with the lateral and the vertical spring stiffness. Eight types of frames: four existing frames and four retrofit frames were analyzed by nonlinear static analysis and nonlinear time history analysis with 20 ground motion records. It was found that the initial stiffness and the strength of the retrofit frames were significantly higher than those of the existing frames. The observed seismic damage of the retrofit frames was decreased to the specified limit. The initial stiffness of the frames with flexible foundation was lower than that of the fixed base resulting to the larger displacement and the higher seismic damage of the structures.รายการ Seismic Analysis of RC Frames with Brick Infill Panel Strengthened by Steel Cage and Expanded Metal(Engineering Journal, 2564-04-30) Phaiboon PanyakapoThe seismic analysis of reinforced concrete infilled frame strengthened by using steel cage and expanded metal was investigated. The strengthening technique of steel cage consisted of steel angle, batten and expanded metal sheet was employed. The brick infill panel was strengthened with ferrocement and expanded metal. The flexible base foundation was considered by modelling the pile foundation with the lateral and the vertical spring stiffness. Eight types of frames: four existing frames and four retrofit frames were analyzed by nonlinear static analysis and nonlinear time history analysis with 20 ground motion records. It was found that the initial stiffness and the strength of the retrofit frames were significantly higher than those of the existing frames. The observed seismic damage of the retrofit frames was decreased to the specified limit. The initial stiffness of the frames with flexible foundation was lower than that of the fixed base resulting to the larger displacement and the higher seismic damage of the structures.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.รายการ 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 Seismic Strengthening of RC Frame and Brick Infill Panel using Ferrocement and Expanded Metal(Engineering Journal, 2563-05-31) Suvawat Longthong; Phaiboon Panyakapo; Anat RuangrassameeThis paper presents the strengthening of reinforced concrete frame and brick infill panel by using ferrocement technique reinforced with expanded metal. Analytical models of the strengthened frame and infill panel were proposed. An experimental study on the strengthened frames was conducted to verify the proposed models. Two control specimens and two strengthened specimens were compared: the bare frame and the infilled frame. Special strengthening techniques were employed to protect against two major failures: the beam and columns of the frame were fully strengthened to prevent shear failure, and the infill panel was protected against corner compression failure. The frames were investigated under constant vertical load and lateral cyclic load. The seismic behavior of the retrofit frames was compared with the control specimens. The strengthened frames showed the significant increase of strength up to 64% and 87%, and the ductility capacity was also improved 77% and 66% for the bare frame and the infilled frame, respectively. The proposed model of strengthening for the frame and infill panel predicted the lateral resistance of the RC infilled frame with a reasonable accuracy when compared to the observed experimental results.รายการ Seismic Shear Strengthening of Reinforced Concrete Short Columns Using Ferrocement with Expanded Metal(Engineering Journal, 2562-11-30) Songkran Panyamul; Phaiboon Panyakapo; Anat RuangrassameeTypical reinforced concrete short column is brittle in shear rather than flexure under lateral cyclic loading due to its shear deficiency. This paper presents the improvement of seismic behaviour of the reinforced concrete short columns which were strengthened by using ferrocement with expanded metal. Full scale experiments were conducted for two strengthened concrete columns with different volume fractions of expanded metal and the control specimen under lateral cyclic loading. It was found that the seismic behaviour in terms of the shear strength, stiffness, displacement ductility, and energy dissipation were significantly improved. The expanded metal mesh with the high specific surface provided the better performance for controlling the crack propagation. The brittle shear failure mode of the stirrup was reduced and the ductile flexure mode of the longitudinal reinforcement was dominant. The reduced shear force of the stirrup was compensated by the shear force of the expanded metal reinforcement which experienced relatively large strain. The technique of steel angle installation at the corners of column can successfully prevent the effect of sharpened corner wrapping of the mesh. A model to predict the shear strength of the strengthened column is presented in term of the global efficiency factor for expanded mental.รายการ Review of Upper Limb Exoskeleton for Rehabilitation and Assistive Application(International Journal of Mechanical Engineering and Robotics Research, 2563-05) Wanayuth Sanngoen; Sarasit SirawattanakulThe purpose of this research is to review upper limb exoskeleton for industrial and rehabilitation application from other researchers such as control system, mechanical design, load transmission methods, and control strategies. They mainly used the upper limb exoskeleton in the field of rehabilitation and power-assist. Electromyogram or EMG and Force sensor are used for measuring the user motion. Moreover, the load transmission methods have a lot of impact in term of speed and torque such as DC motor with gearbox, DC motor with driving wire, servo motor, and more. In this works, we study the various technique before design and develop the upper limb exoskeleton for supporting who is a disability of upper limb motion, to be more precise, low-cost, lightweight material, modern control algorithm, and capability upper limb motion.รายการ Implementation of Fall Detection for WAR-Exoskeleton Robot(2563-01-01) Wanayuth Sanngoen; Pathid LiamtrakoolpanichIn this paper, we presented a method of detecting the state of the lower limb exoskeleton for a fall detection function based on the WAR exoskeleton robot platform. While in motion, the exoskeleton is to follow the gait pattern data. The exoskeleton functions on distributive control where the hip joints and knee joints are controlled by the PID controller. Several equations are derived which outlines the conditions needed to keep the exoskeleton balanced and unlikely to fall. Deviations from the expected patterns and angle changes in the exoskeleton robot may cause instability and imbalance. Experimental results on the moment during leg motion and positional changes of the centroid while robot is in motion are obtained and used as conditions for fall detection. The method proposed is effective for fall detection in war-exoskeleton robot.รายการ พฤติกรรมการวิบัติของพื้นคอนกรีตเสริมเหล็กเสริมกำลังด้วย CFRP ที่ความเหนียวตํ่า(มหาวิทยาลัยศรีปทุม, 2561-12-20) ชัชวาลย์ พูนลาภพานิช; ณัฐวัฒน์ จุฑารัตน์Two Reinforced concrete one-way slabs with the cross section of 0.10 m x 0.63 m and 2.4 m span length were designed for the live load of 400 kg/m2. One of them was then strengthened according to ACI 318-05 with the 6 layers of CFRP to increase the live load resistance to 800 kg/m2 aiming to fail by CFRP debonding at low ductility range or with the flexural strength reduction factor, , of 0.76 . Third point loading test showed the debonding failure at the interface of CFRP and concrete during yielding of the rebars. The load carrying capacity of strengthen slab was less than predicted ultimate capacity. The maximum tensile strain of outermost carbon fiber sheet was 0.001371 which is also lower than expected standard value. The evaluation of the flexural strength reduction factor, , based on the ultimate strain of rebar is 0.75. The test results showed that CFRP slab strengthening in case of very low ductility may be hardly controlling failure behavior. The proper installation of strengthening system must be conducted under close supervision of licensed engineers and more research in this topic is needed.รายการ เครื่องวัดคุณภาพน้ำยางพาราด้วยระบบดิจิตอล(SPU Conference2018, 2561-12) นิมิต บุญภิรมย์; พัศวีร์ ศรีโหมด; จรัล สว่างอรุณ; นิติพงศ์ ขุนทองบทความฉบับนี้เป็นการออกแบบและสร้างเครื่องวัดคุณภาพน้ำยางพาราด้วยระบบดิจิตอล โดยวัตถุประสงค์จะเป็นการสร้างเครื่องวัดคุณภาพของน้ำยางพาราเพื่อใช้วัดประเมินคุณภาพประกอบกระบวนซื้อขายน้ำยางพาราในระดับท้องถิ่นที่ใช้การอบไล่ความชื้นในน้ำยางพาราด้วยเตาไมโครเวฟก่อนนำมาชั่งเพื่อประเมินคุณภาพของน้ำยางพาราทำให้ใช้เวลานานและไม่แม่นยำ เครื่องวัดคุณภาพน้ำยางพาราที่ได้นำเสนอนี้จะใช้หลักการวัดความหนืดของน้ำยางพาราโดยใช้หลักการปล่อยลูกตุ้มเหล็กที่บรรจุน้ำยางพาราที่ต้องการวัดในหลอดแก้วขนาด 250 มิลลิลิตร และจับเวลาการเคลื่อนที่ของลูกตุ้มผ่านน้ำยางพาราจากปลายหลอดแก้วถึงก้นหลอดแก้ว น้ำยางพาราที่มีความเข้มข้นต่างกันจะได้เวลาการเคลื่อนที่ของลูกต้มเหล็กที่แตกต่างกัน แสดงถึงคุณภาพของน้ำยางพาราในรูปความเข้มข้นหรือมีส่วนผสมของน้ำที่แตกต่างกัน การควบคุมลูกตุ้มและจับเวลาจะประยุกต์ใช้ไมโครคอนโทรลเลอร์ AVR เบอร์ MEGA16 ควบคุมการทำงานและตัวตรวจจับโลหะ เพื่อตรวจสอบเมื่อลูกตุ้มตกถึงก้นของหลอดแก้ว และแสดงผลของเวลาและคุณภาพออกจอ LCD เครื่องวัดคุณภาพน้ำยางพาราเราสามารถนำเครื่องวัดคุณภาพน้ำยางพาราเพื่อเปรียบเทียบกับการวัดด้วยการอบแบบดั้งเดิมและเครื่องมือวัดคุณภาพน้ำยางพารานี้ช่วยให้เกษตรกรชาวสวนยางพาราประหยัดเวลาและเพิ่มความเที่ยงตรงในการหาคุณภาพน้ำยางพารารายการ การศึกษาระบบไฟส่องสว่างบนทางวิ่งและทางขับของสนามบินพานิชย์(SPU Conference2018, 2561-12) นิมิต บุญภิรมย์; กษิเดช ทิพย์อมรวิวัฒน์; ฐาภพ จันทรสุข; ภาดา เสนีย์วงศ์ ณ อยุธยาบทความนี้เป็นการนำเสนอการศึกษาระบบไฟส่องสว่างทางวิ่งและทางขับของสนามบินพานิชย์ โดยมีรายละเอียดหลักคือระบบแสงสว่างเพื่อให้สัญญาณของทางวิ่งและทางขับของสนามบินพานิชย์ขนาดใหญ่เนื้อหาจะกล่าวถึงระบบแสงสว่าง โคมไฟฟ้าชนิดต่าง ๆ โดยแบ่งแยกตามฟังก์ชันตามกระบวนการในส่วนต่าง ๆของการขึ้นลงของอากาศยานหรือเครื่องบิน ความเข้มของการส่องสว่างของโคมไฟฟ้าทั้งในระบบทางวิ่งและทางขับ อ้างอิงตามมาตรฐาน ICAO ANNEX 14 VOLUME 1-9 ระบบการควบคุมการจ่ายกำลังไฟฟ้าด้วยแหล่งจ่ายกำลังไฟฟ้าแบบกระแสคงที่ วงจรการทำงานของตัวควบคุม และวงจรการควบคุมโคมไฟฟ้าแบบอนุกรม เพื่อเป็นข้อมูลพื้นฐานเผยแพร่ต่อผู้ปฏิบัติงานด้านไฟส่องสว่างของทางวิ่งและทางขับของงานไฟฟ้าสนามบิน
