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The main emphasis of this paper is on the power quality based comparison of two identical systems modeled in ETAP, one comprising CFLs as lighting load and the other has fluorescent lights as lighting source. Current waveforms along with its spectrum for the HTs (High Tension side) and LTs (Low Tension side) of distribution transformers, voltage waveforms and their spectrum at different buses have been compared in terms of THDv and THDi at various locations.

Abstract This study newly introduces a complementary cooperative algorithm considering generative adversarial network (GAN)-Conditional Latent Space (CLS) combined with bidirectional long short-term memory (BLSTM) for improved and efficient lithium-ion rechargeable battery state prediction. The GAN-CLS algorithm, which is an advanced method of GAN, can generate corresponding images from an input label description. Long short-term memory (LSTM) is a specific recurrent neural network (RNN) architecture that can predict sequences more accurately than conventional RNNs. In terms of battery state prediction, the combination of two methods (GAN-CLS and LSTM) surely provides more improved and efficient rechargeable battery state prediction in contrast to conventional state predictors. The procedure of this study is as follows. First, we propose methods to enhance the data from battery charge/discharge by converting prepared data to images; then, the GAN-CLS method is used to generate corresponding battery data from previous images. Subsequently, the generated data is used to train the BLSTM model. Finally, the trained model is used to predict the battery state. By various experiments and verification, it is concluded that the proposed study can be a good solution for rechargeable battery state prediction (reduction of the time cost 50 times in modeling and 20 times in train/test, provision of a more accurate prediction mean square error (MSE) smaller than 0.0025 and the average MSE less than 0.0013).

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Exterior insulation finishing systems (EIFSs) can efficiently promote energy efficiency of buildings. In this study, an EIFS with high thermal efficiency is presented to improve the insulation behavior of building enclosure. Based on heat transfer analysis results, energy simulations of buildings with fire spread prevention structures were performed. Results revealed that heat flow through the wall increased by 10.3 % when using a metal rail to fix the insulation; in contrast, using non-combustible phenolic foam reduces heat flow by 37.4 %, satisfying the requirement for fire spread prevention structures. Additionally, the energy consumption decreased by 8.8 % when both mineral wool and phenolic foam were applied. Fire spread prevention structures are essential to improve the fire safety performance of buildings. This external insulation system efficiently promote energy saving in building; additionally, leveraging a phase change material to improve the thermal storage performance of the building can reduce energy consumption by up to 11.9 %.

AbstractIn Korea, seven species belonging to five genera of the family Bostrichidae have been recorded to date. To these seven species, we are adding four other species, namely, Psoa rubripennis sp. nov., Dinoderus speculifer Lesne, 1895, Heterobostrychus hamatipennis (Lesne, 1895), and Xylothrips pekinensis (Lesne, 1902: comb. nov.) to the Korean fauna. In addition, the genus Calophagus Lesne, 1902, is synonymized with the genus Xylothrips Lesne, 1901 (syn. nov.) and Xylothrips cathaicus Reichardt, 1966, is synonymized with X. pekinensis (Lesne, 1902: syn. nov.). We herein present the key to the identification of species of the Korean Bostrichidae family and three similar Xylothrips species in Asia using their photographs.

Abstract This paper addresses three main subjects in supercritical heat transfer: (1) difference in thermal characteristics between upward and downward flows; (2) effect of simulating flow channel shape; (3) evaluation of the existing supercritical heat transfer correlations. To achieve the objectives, a series of experiments was carried out with CO2 flowing upward and downward in a circular tube with an inner diameter of 4.57 mm and an annular channel created between a tube with an inner diameter of 10 mm and a heater rod with an outer diameter of 8 mm. The working fluid, CO2, has been regarded as an appropriate modeling fluid for water, primarily because of their similarity in property variations against reduced temperatures. The mass flux ranged from 400 to 1200 kg/m2 s. The heat flux was varied between 30 and 140 kW/m2 so that the pseudo-critical point was located in the middle of the heated section at a given mass flux. The measurements were made at a pressure of 8.12 MPa, which corresponds to 110% of the critical pressure of CO2. The difference between the upward and downward flows was observed clearly. The heat transfer deterioration was observed in the downward flow through an annular subchannel over the region beyond the critical point. Several well-known correlations were evaluated against the experimental data, and new correlations were suggested for both a tube and an annular channel.

Nowadays, wave energy plays an important role in renewable energy resource. In over thirty years, researches in wave energy converter system (WEC) have been deployed and carried out. This paper presents a design of wave energy converter using 5 cylinders combining with hydraulic power take-off system in order to convert the mechanical energy from ocean wave to electricity, or another useful and usable source. The WEC uses ordered 5 cylinders to represent the motion of the floating buoy under the wave elevation. The design and specification of the WEC system are presented. Buoy and wave interaction mathematical model is built and the hydraulic mathematical model is also presented. The system performance test is implemented and the result is shown.

In this study, numerical simulations and performance evaluation has been carried out to investigate performance characteristics of air-type high pressure piston pump. ANSYS and CFX were applied for analyzing the structure and flow behavior of air-type high pressure piston pump, respectively. The performance evaluation of high pressure piston pump was performed experimentally, the results were compared with simulation. It was found that the freezing phenomenon was improved by 20% and the pressure fluctuation decreased by 50%, compared with the previous pump.