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"The performance of a 20 MW gas turbine power plant was described by using the exergy analysis and data from the plant?s record books. The first and second laws of thermodynamics, as well as the mass and energy conservation law, were applied in each of the components. The results show that more exergy destruction occured in the combustion chamber up to 71.03% or 21.98 MW. Meanwhile, the lowest exergy occured in the compressor at 12.33% or 3.15 MW. Thermal efficiency of the gas turbine power plant, according to the first law, was 33.77%, and exergy efficiency was 32.25%."

"The performance of a 20 MW gas turbine power plant was described by using the exergy analysis and data from the plant’s record books. The first and second laws of thermodynamics, as well as the mass and energy conservation law, were applied in each of the components. The results show that more exergy destruction occured in the combustion chamber up to 71.03% or 21.98 MW. Meanwhile, the lowest exergy occured in the compressor at 12.33% or 3.15 MW. Thermal efficiency of the gas turbine power plant, according to the first law, was 33.77%, and exergy efficiency was 32.25%."

"Commercialization ofbioethanol has recently intensified due to its market stability, low cost,sustainability, alternative fuel energy composition, greener output andcolossal fossil fuel depletion. Recently, because of greenhouse intensityworldwide, many researches are ongoing to reprocess the waste as well asturning down the environmental pollution. With this scenario, the invention ofbioethanol was hailed as a great accomplishment to transform waste biomass tofuel energy and in turn reduce the massive usages of fossil fuels. In thisstudy, our review enlightens various sources of plant-based waste feed stocksas the raw materials for bioethanol production because they do not adverselyimpact the human food chain. However, the cheapest and conventionalfermentation method, yeast fermentation is also emphasized here notably forwaste biomass-to-bioethanol conversion. Since the key fermenting agent, yeastis readily available in local and international markets, it is morecost-effective in comparison with other fermentation agents. Furthermore, yeasthas genuine natural fermentation capability biologically and it produces zerochemical waste. This review also concerns a detailed overview of the biologicalconversion processes of lignocellulosic waste biomass-to-bioethanol, thediverse performance of different types of yeasts and yeast strains,plusbioreactor design, growth kinetics of yeast fermentation, environmentalissues, integrated usages on modern engines and motor vehicles, as well asfuture process development planning with some novel co-products."

"An active Radio-Frequency Identification (RFID) tag is a low-power device, which is often used as a tracking device, where operation of this tag will be in remote areas from an electrical power source. Therefore, this device requires an independent power source. To meet these needs, solar power may be used, which can be accessed anywhere there is sunlight. Supercapacitors (SC) are used as an energy source to support a solar power system. The advantage of supercapacitors, as an energy storage device, is their long life cycle that means more charging and discharging processes compared to a conventional battery. The design and fabrication of a solar power system for an active RFID tag with supercapacitors as the energy storage will be covered in this paper."

"We propose a simple design of 1×3 optical power splitter which uses gallium nitride (GaN) on sapphire. The design consists of widely used large cross section input rib waveguide, a rectangular multimode interference (MMI) structure, and three-branch rib waveguides. The MMI structure is selected since their attractive performances, such as compactness, low excess loss, wide bandwidth and ease to fabricate. The power splitter is designed for the third telecommunication window, i.e., l = 1.55 µm. Optimization of the geometrical structure parameters for the design is conducted theoretically utilizing 3D FD-BPM method. It is found that the power splitter exhibits excess loss of 0.46 dB and imbalanced of 0.001 dB at l = 1.55 µm for ..."

"The gas diffusion layer (GDL) is one of the critical components of a proton exchange membrane fuel cell (PEMFC). It is generally made of a fossil-fuel-based carbon material. In this study, carbon composite paper (CCP) for GDL was prepared by using carbon material obtained from coconut coir. To obtain the CCP, 80 wt% carbon material from the coconut coir and 20 wt% polymer binder (ethylene vinyl acetate and polyethylene glycol) were mixed in xylene solvent at 100°C, cast on molded glass, and then rolled. The carbon material consists of a mixture of carbon fibers (length: 2 mm) and powders (size: 74 µm). Subsequently, the CCP was treated with polytetrafluoroethylene solution (10 wt%). The physical properties of the CCPs, such as through-plane electrical conductivity, porosity, density, and hydrophobic properties, were investigated. Scanning electron microscopy and energy-dispersive spectroscopy mapping were used to analyze the morphology and polytetrafluoroethylene (PTFE) distribution in the CCP. The through-plane conductivity test showed that CCP with 70 wt% carbon fiber, 10 wt% carbon powder, and 20 wt% polymer was the optimum sample, and it showed the highest electrical conductivity of 2.22 S cm-1. The physical properties of PTFE-treated CCP, such as porosity, density, and contact angle, were almost similar to that of commercial carbon paper used as a GDL. Therefore, the CCP prepared from coconut coir can be applied as a GDL in a PEMFC."

"Barium strontium titanate (BST) or Ba1-xSrxTiO3 with x=0-1 possesses superior dielectric properties, which are widely used in many applications like in communication technology, electronic instrumentations, and various electrical devices. In this paper, the characterization of the particle and crystallite size of Ba1-xSrxTiO3 (x: 0; 0.3; 0.7) is described. A two-step refinement commenced: first by mechanical milling, and then a further refinement under ultrasonic irradiation in a high power sonicator was applied to Ba1-xSrxTiO3 (x: 0; 0.3; 0.7) particles. The crystalline powders were obtained through mechanically alloyed standard research grade BaCO3, TiO2, and SrCO3 precursors in a planetary ball mill.The powders were first found heavily deformed after 60 hours of milling and then went through a sintering process at 1200°C for 4 hours to form multicrystallite particles. The presence of a single phase in the three samples was solidly confirmed in their respective X-ray diffraction (XRD) patterns. The changes of multicrystallite particles into monocrystallite particles were obtained only after crystalline powders were irradiated ultrasonically in a high power sonicator. The processing variable during ultrasonic irradiation was limited to the duration time of irradiation and particle concentration in the exposed media. It is shown that the average sizes of BST particles at x=0; 0.3; 0.7 before ultrasonic irradiation were 353, 348, and 385 nm, respectively. These respective sizes decreased drastically to 52, 35, and 49 nm, respectively, after 12 hours of ultrasonic irradiation. These particle sizes are almost identical with that of their crystallite size. Hence, the synthesis of monocrystallite particles has been achieved. As the particle concentration of media takes effect, it is shown that an exposed media with a higher particle concentration tends to form multicrystallite particles."

"Wireless 3.5G is designed to deliver various kind of multimedia packages through IP network. Quality of Service (QoS) fulfilment is a crucial factor for multimedia applications...."

"Todevelop seismic design criteria for buildings, seismic hazard analysis is required to estimate the ground motionintensity with criteria such as peak groundacceleration (PGA). The seismic hazard can be analyzed by using two approaches: deterministic seismic hazard analysis (DSHA) andprobabilistic seismic hazard analysis (PSHA). In these two approaches, theseismic hazard is evaluated from past earthquake events and active faults data. In Thailand, seismic hazard is classified in the low lying regions; however, in recently years,earthquakes have occurred frequently in the North of Thailand. Toprevent and reduce damage due to earthquakes in the future, determinationof seismic hazard is needed. Thisresearch proposes a deterministic seismic hazardmap evaluated from nineteenactive faults affectingThailand. Two types of active faults are considered: first, an active fault in a subduction zone and second, a crustal fault. The seismic hazard is evaluated by using a groundmotion prediction equation (GMPEs). Four GMPEs are weighted equally forseismic crustal fault, and two GMPEs are weighted equally fora seismic subduction zone. The hypocentral distance isused to evaluate the seismic hazard for all ground motion prediction equations.The Northern part and the Western part of Thailand are high seismic hazardregions, because there are active faults with the large possibility of earthquakes of a maximum magnitude. The seismichazards in the North, West and Northeast of Thailand are about 0.60 g.The seismic hazard in Bangkok is about 0.25 g due to the Three Pagoda fault and Sri Sawat fault. The seismic hazard in the South of Thailand is about 0.40 g."

"The cloud is an outstandingplatform to deal with functionally equivalent services which are exponentiallyincreasing day-by-day. The selection of servicesto meet the client requirements is a subtle task. The services can be selected byranking all the candidate services using their network and non-network Quality-of-Service (QoS) parameters, which is formulated as a NP hard optimization problem. In this paper, weproposed a linear discriminant analysis (LDA) based a four level matching model for service selection based on QoS parameters,which includes description matching of a service, matchmaking phase, LDA-based QoS matching and ranking. The LDA-serviceselection agent is deployed on each cloud to classify services into classes andrank the services based on the aggregate QoS value of each service. Finally,the test results show the efficiency in service selection with minimaldiscovery overhead, significant reduction in the computation time and thenumber of candidate services to be considered."