• Journal of Hydrogen and New Energy
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• v.25 no.3
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• pp.311-318
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• 2014

Performance degradation of a battery in 20 kWh energy storage system (ESS) under various operating conditions was studied. And energy saving of the ESS was also monitored by connecting with 20 kW photovoltaic (PV). PV-connected ESS saved 5~7% of energy consumption in 2013 compared to that without such system in 2012. As charge-discharge cycle increased, capacity decreased and the performance degradation was glaringly obvious after 40 cycles. And as charge and discharge rate increased, the performance degradation was more serious. After 50 charge-discharge cycles, a lot of degraded product was deposited on the surface of anode and cathode electrodes, and the cathode side was more contaminated. Therefore, in order to maintain the cell performance, it was more important to protect the degradation of the cathode side.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.32 no.8
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• pp.668-677
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• 2008

In nuclear power plants, ferritic low alloy steel nozzle was connected with austenitic stainless steel piping system through alloy 82/182 butt weld. Accurate estimation of residual stress for weldment is important in the sense that alloy 82/182 is susceptible to stress corrosion cracking. There are many results which predict residual stress distribution for alloy 82/182 weld between nozzle and pipe. However, nozzle and piping system usually connected through safe end which has short length. In this paper, residual stress distribution for pressurizer nozzle of Kori nuclear power plant was predicted using FE analysis, which consideded safe end. As a result, existing residual stress profile was redistributed and residual stress of inner surface was decreased specially. It means that safe end should be considered to reduce conservatism when estimating the piping system.

• Journal of Korean Medical classics
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• v.25 no.2
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• pp.1-13
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• 2012

Objective : Zhang, Zhongjing(張仲景)'s Sanghanlun(傷寒論) is based on Six-channels system(六經) to classified a disease. But the notion of Six-channels system seems to be a very various angles. For example, Meridian and collateral theory(經絡說), Viscera and Bowels theory(臟腑說), Grade theory(段階說), Surface theory(地面說), Symptoms theory(症候群說), Six-disease theory(六病說), Eight principle pattern theory(八綱說) and all the rest of it. Above all things Meridian and collateral theory was very frequently quoted to explain the Six-channels system(六經). But it's true notion is not restrict to a meridian vessel(經脈). Method : I will try to describe the Sanghanlun's Greater yang disease(太陽病) through the Ke-qin(柯琴)'s Taiyangbingjie(太陽病解), and I would like to point out that the existing perception that Greater yang(太陽) is connected with Bladder meridian(足太陽膀胱經) is wrong. Result : Ke-qin's Taiyangbingjie explained the greater yang disease was connected with Heart(yang within yang), which was located in the top half and the outer layer of the body. In addition to the presence of the diaphragm or lungs are involved with. Conclusion : Practical meaning of greater yang disease is not connect with Bladder meridian, but it is related to the Heart and Lung for maintain the Nutrient and defense circulation (營衛循環).

• Journal of the Korean Society of Hazard Mitigation
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• v.10 no.6
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• pp.99-108
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• 2010

In this study, the characteristics of flow within and around a crossroad connected symmetrically with four roads are numerically analyzed by using a two-dimensional well-balanced HLLC finite volume model. As results of simulations and analyses, the numerical model employed in this study describes relatively well the complex water surface in a crossroad according to the conditions of inflow and road slope. Moreover, the predicted temporal and spatial variations of water depths in a crossroad and outflows at two downstream boundaries agree relatively well with laboratory measurements.

• Journal of Veterinary Clinics
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• v.16 no.2
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• pp.409-412
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• 1999

To establish the electroacupuncture anesthesia for pigs, 6 piglets (Landrace mixed, 1 month old, 3.7~5.3 kg, female: 3 heads and male: 3 heads) were examined. The acupoints used for porcine electroacupuncture anesthesia were An-shen, and Tian-ping and Bai-hui. After horizontal insertion of needle to left and right An-shen, and perpendicular insertion to Tian-ping and Bai-hui, respectively, positive electrode was connected at right An-shen and Tian-ping, and negative electrode was connected at left An-shen and Bai-hui using veterinary electroacupuncture anesthesia apparatus, respectively. Electric condition was 3 V and 30 Hz. To examine the effect of electroacupuncture anesthesia, laparotomy (4 heads) and castration (2 heads)were applied. The induction time of electroacupuncture anesthesia was very rapid and about 1 minute, and pain of the body surface including the extremities was not detected. As for the reactions with electroacupuncture anesthesia, the head was directed to backward, nasal part was curved to one side, and blepharum was closed in part of changed nasal part. In addition, consciousness was vivid, and muscle tension and lift of the tail were observed in early stage but was relaxated afterwards. The pain was not found during incision and suture, bleeding was comparatively small volume and the class of anesthesia effect was excellent.

• Journal of Veterinary Clinics
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• v.16 no.2
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• pp.417-421
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• 1999

To establish the electroacupuncture anesthesia for experimental animal, 5 adult rabbits (Newzealand-white species) and 6 rats (Spraque-dawley) were examined. The acupoints used for electroacupuncture anesthesia were Tian-ping and Bai-hui. After perpendicular insertion of needle to the acupoints, positive electrode was connected at Tian-ping and negative electrode was connected at Bai-hui using veterinary electroacupuncture anesthesia apparatus, respectively. Electric conditions were 2~3 V and 30 Hz in rabbits, and 1.5~2 V and 30 Hz in rats, respectively. To examine the effect of electroacupuncture anesthesia, laparotomy (2 heads), castration (2 heads) and ovariohysterectomy (1 head) were applied in rabbits, and laparotomy (5 heads) and castration (1 head) were peformed in rats, respectively. The induction time of electroacupuncture anesthesia was very rapid and approximately 1 minute, and pain of body surface including the extremities was not detected in rabbits and rats. As for the reactions with electroacupuncture anesthesia, consciousness was vivid, blepharoreaction was not observed and the tail was up at early stage but was down afterwards in rabbits. The same findings except cotinuous lifting of the tail were observed in rats. The pain was not observed during incision and suture, bleeding was comparatively small volume and the class of anesthesia effect was excellent.

• Journal of the Korean Institute of Telematics and Electronics
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• v.26 no.7
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• pp.140-145
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• 1989

In this paper, we present an effective circuit placement method called SOAP (self-organization assisted placement) for rectilinear or arbitrarily-shaped region arised form the layout of ASIC (application specific integrated circuit). Self-organization is a learning algorithm for neural networks proposed by [1] which adjusts weights of synapses connected to neurons such that topologically close neurons are sensitive to inputs that are physically similar. In SOAP, we obtain a good circuit placement result in arbitrarily-shaped region by replacing the block of circuit and the position (x, y coordinates) of the block with the neuron and the weight pair of synapses connected to the neuron, respectively. This method can also be extended to the circuit placement over the nonplanar surface.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.66 no.4
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• pp.643-650
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• 2017

This pap4er analyzes resonance characteristics of a slave motor that is not controlled by load and parameter differences between Dual motors during parallel operation in middle-low speed. Dual SPMSMs(Surface mounted Permanent Magnet Synchronous Motor) connected in parallel to a single inverter controlled by the master and slave control in this paper. Based on the stability analysis of the SPMSM for a variation of torque angle, the 6th nonlinear state equation of the torque angle variation in the SIMM(Single Inverter Multi Motor) structure is derived according to a mathematical model for the dual motors. In general, an analysis of the 6th order nonlinear state equation is complex. Therefore, a resonance frequency generated from the slave motor is found from the characteristic equation of the 2nd order system obtained by linearization and model reduction near steady state operation point. Through simulations and experiments, it is confirmed that the stability analysis of the SPMSMs and state equation models are useful for the variation of the torque angle analyzed in this paper.

• Transactions of the Korean Society of Automotive Engineers
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• v.22 no.2
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• pp.23-28
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• 2014

This study investigates fluid flow and thermal stress at automotive exhaust manifolds as model 1 and 2. The maximum displacements happen at joint part connected with 4 pipes and upper middle of both parts in cases of model 1 and 2 respectively. At inner surface of the part connected with engine, maximum equivalent stresses of 991.85 and 698.96 MPa are shown in cases of model 1 and 2 respectively. As maximum velocities at the outlet at model 1 are shown at 19.46 and 14.61 m/s in cases of model 1 and 2 respectively, model 1 has more pressure drop than model 2. As result, model 2 has less pressure drop than 1. Model 2 has less deformation and stress than model 1. Model 2 has also less pressure drop than model 1. Therefore model 2 has more strength durability than model 1. This study result is applied with the design of safe automotive manifold and it can be useful to improve the durability by predicting prevention against the deformation due to exhaust gas.

• Journal of Korea Water Resources Association
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• v.46 no.7
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• pp.767-781
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• 2013

In this study, the hydraulic model experiments and numerical simulations are carried out to analyze the flood flow characteristics in and around a channel confluence connected asymmetrically with four channels. The numerical model applied in this study is ANSYS CFX (ver. 14) which is the commercial three-dimensional CFD model. As results of comparison between the measured and simulated water depth distributions in and around a channel confluence, the agreement is relatively well satisfied. It can be shown in this study that the water surface profiles in and around a channel confluence are significant different with the two channel directions in which the water are entering and increased inflow.