• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.28 no.12
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• pp.116-123
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• 2014

In case of power electronics, th power loss and EMI noise of IGBT is different depends on a adopting technology with the same power rating. To reduce the EMI noise, we could increase the resistance of gate. But in this case, the power loss of IGBT is increased, In this paper, we simulated the power loss of IGBT with the speed profile of elevator by the changing IGBT type, the voltage between gate and emitter, the resistance of gate in converter and inverter for elevator. To optimize the power electronics with the satisfied life time, It is necessary that we calculate the power loss and the rise of temperature in IGBT with the adopting technology type, the resistence of gate, the voltage between gate and emitter.

• Journal of Korean Medical classics
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• v.27 no.1
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• pp.77-87
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• 2014

Objective : The writer has come to see that a study of the Theory of Ministerial Fire of JuDanGae presupposes a study of earlier theories of fire. Therefore, I have analyzed and studied the theories of fire presented by medical doctors since "Nae Gyeong(黃帝內經)" Method : To begin with, I have studied the concepts of grand fire(壯火) and small fire(少火), imperial fire(君火) and ministerial fire(相火) in "Nae Gyeong", and have construed the meaning of human fire(人火) and dragon fire(龍火) by Wang Bing(王冰), and fatty fire(膏火) by Sohn Sa-mak(孫思邈). Next, I have studied true fire(眞火) by Huh Sook-mi(許叔微) and true yang(眞陽) and pit fire(坎火) by Eom Yong-hwa(嚴用和), Theory on Right Kidney as the Gate of Life and Ministeiral Fire(右腎命門相火說) by Yu Wan-so(劉完素), and the reason why Jang Wan-so(張元素) asserted Theory of Three Burners as Ministerial Fire(三焦相火說). Result : I have understood the influence that the concepts of grand fire and small fire, imperial fire and ministerial fire in "Nae Gyeong"have exercised on the later medical doctors, and have also understood the physiological and pathological Fire that influences the human body. Moreover, I have seen that Fire, as discussed by scholars from Huh Sook-mi and Eom Yong-hwa to Yu Wan-so and Jang Wan-so, made great contribution to the later development of Theory of the Gate of Life, getting its entire picture in Eum Hwa. Conclusion : Seeing that the theories of Fire presented by medical doctors since "Nae Gyeong" and prior to JuDan-Gae had great influence on the later development of Theory of the Gate of Life, I have come to understand that along with Eum Hwa by Lee Dong-wan, they must precede a study of the Theory of Ministerial Fire of JuDan-Gae.

• The Journal of Korean Medicine
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• v.17 no.2 s.32
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• pp.88-99
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• 1996

Impotence is defined as a consistent inability to achieve or maintain penile erection that is adequate for completion of sexual intercourse. In oriental midicine, the chief cause of impotence is the decline of the fire from the gate of life, and in western medicine that is psycogenic and organic. Because of the increase aging people and psycologic stress that modern people get, impotence became common. This bibliographic study on impotence in the oriental and western medicine books has come to the following conclusions. 1. The main cause of impotence in the oriental medicine is the decline of the fire from the gate of life(命門火衰), followed by the deficiency of both heart and spleen(心脾兩虛), the depression of Liver energy(肝氣鬱結), and attack of blended wetness and heat to the lower wanner(濕熱下注). 2. The theraphics of impotence in oriental medicine are warming and strenghthening Kidney. softness of Liver energy, tonifying the Kidney to relieve mental strain, clear away the wetness-heat, and infairment of Heart and Spleen. 3. The prescriptions of impotence are Yugyeyum, Gyibitang, Soyosan, Sunjitang, and Yongdamsagantang. 4. In the western medicine, psycotherapy, medical therapy and surgical therapy are the major way to treat impotence.

• Nuclear Engineering and Technology
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• v.54 no.6
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• pp.2107-2119
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• 2022

Accurate remaining useful life (RUL) prediction for critical components of nuclear power equipment is an important way to realize aging management of nuclear power equipment. The electric gate valve is one of the most safety-critical and widely distributed mechanical equipment in nuclear power installations. However, the electric gate valve's extended service in nuclear installations causes aging and degradation induced by crack propagation and leakages. Hence, it is necessary to develop a robust RUL prediction method to evaluate its operating state. Although the particle filter(PF) algorithm and its variants can deal with this nonlinear problem effectively, they suffer from severe particle degeneracy and depletion, which leads to its sub-optimal performance. In this study, we combined the whale algorithm with regularized particle filtering(RPF) to rationalize the particle distribution before resampling, so as to solve the problem of particle degradation, and for valve RUL prediction. The valve's crack propagation is studied using the RPF approach, which takes the Paris Law as a condition function. The crack growth is observed and updated using the root-mean-square (RMS) signal collected from the acoustic emission sensor. At the same time, the proposed method is compared with other optimization algorithms, such as particle swarm optimization algorithm, and verified by the realistic valve aging experimental data. The conclusion shows that the proposed method can effectively predict and analyze the typical valve degradation patterns.

• Proceedings of the PSK Conference
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• 2005.11a
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• pp.130-130
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• 2005

• Journal of The Korean Society of Agricultural Engineers
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• v.53 no.3
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• pp.59-64
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• 2011

The objective of the study is to develop life cycle inventory (LCI) database of dam, a major facility for irrigation water supply. The types of database developed are three out of nine dams according to the size of the wate r storage capacity: two kinds larger than 500,000 $m^3$ depending on gate for discharging (Type 1) and the other dam smaller than 500,000 $m^3$ (Type 2). According to the LCI analysis, type 1 larger than 500,000 $m^3$ storage capacity with gate has the lowest environment impact in the 6 impact categories. The impact of the type 1 accounts for 7~35 % of the type 2 for supplying irrigation water. Comparing with the environment impacts of water for other uses such as drinking and industrial water, the impacts of 1 $m^3$ irrigation water supply is 4~45 % of the one for industrial water supply and 1~16 % of the drinking water's. The three types of LCI DB on the irrigation water by dams will be useful in the application of Life Cycle Assessment in agricultural products and environmental labelling including carbon footprint since it is complied to the guidelines of LCI DB constr uction issued by Ministry of Environment and Ministry of Knowledge Economy.

• Journal of the Korean Society of Safety
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• v.29 no.1
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• pp.7-14
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• 2014

Inverter module, which feeds the converted power to the traction motor for EMU. Consists of the power semiconductors with their gate drive unit(GDU)s and the control computer for driving, voltage, current and speed controls. Electrolytic condenser, connected to the gate drive unit and a core component to drive the power semiconductor, has problems such as reduction in lifetime and malfunction caused by electrical and mechanical characteristic changes from heat generation during high speed switching for generation of stable power. In this study, To check the service life of electrolytic condenser, the test was carried out in two ways. First, In the case of accelerated life testing of condenser, the Arrhenius model is a way of life testing. Another way is to analyze the reliability of the failure data by the method of parametric data analysis. Eventually, life time by accelerated life test than a method of failure data analysis(Weibull distribution) was found to be slightly larger output.

• Animal cells and systems
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• v.11 no.2
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• pp.169-173
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• 2007

Hyperpolarization-activated nonselective cation channels (HCNs) play a pivotal role in producing rhythmic electrical activity in the heart and the nerve cells. In our previous experiments, voltage-dependent $Cd^{2+}$ access to one of the substituted cysteines in S6, T464C, supports the existence of an intracellular voltage-dependent activation gate. Direct binding of intracellular cAMP to HCN channels also modulates gating. Here we attempted to locate the cAMP-modulated structure that can modify the gating of HCN channels. SpHCN channels, a sea urchin homologue of the HCN family, became inactivated rapidly and intracellular cAMP removed this inactivation, resulting in about eight-fold increase of steady-state current level. T464C was probed with $Cd^{2+}$ applied to the intracellular side of the channel. We found that access of $Cd^{2+}$ to T464C was strongly gated by cAMP as well as voltage. Release of bound $Cd^{2+}$ by DMPS was also gated in a cAMP-dependent manner. Our results suggest the existence of an intracellular cAMP-modulated gate in the lower S6 region of spHCN channels.

• International conference on construction engineering and project management
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• 2022.06a
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• pp.975-983
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• 2022

This paper presents an innovative way of integrating scheduling and project controls with the environmental impact of a construction project to track, monitor, and manage environmental emissions at the activity level. As a starting point, scheduling and project controls help monitor the status of a project to provide an assessment of the duration and sequence of activities. Additionally, project schedules can also reflect resource allocation and costs associated with various phases of a construction project. Owners, contractors and construction managers closely monitor tasks or activities on the critical path(s) and/or longest path(s) calculated through network based scheduling techniques. However, existing industry practices do not take into account environmental impact associated with each activity during the life cycle of a project. Although the environmental impact of a project may be tracked in various ways, that tracking is not tied to the project schedule and, as such, generally is not updated when schedules are revised. In this research, a Cradle to Gate approach is used to estimate environmental emissions associated with each activity of a sample project schedule. The research group has also investigated the potential determination of scenarios of lowest environmental emissions, just as project managers currently determine scenarios with lowest cost or time. This methodology can be scaled up for future work to develop a library of unit emissions associated with commonly used construction materials and equipment. This will be helpful for project owners, contractors, and construction managers to monitor, manage, and reduce the carbon footprint associated with various projects.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.41 no.2
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• pp.157-164
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• 2017

A parallel slide gate valve (PSGV) is located between the heat recovery steam generator (HRSG) and the steam turbine in a combined cycle power plant (CCPP). It is used to control the flow of steam and runs with repetitive operations such as startups, load changes, and shutdowns during its operation period. Therefore, it is necessary to evaluate the fatigue damage and the structural integrity under a large compressive thermal stress due to the temperature difference through the valve wall thickness during the startup operations. In this paper, the thermal-structural analysis and the fatigue life evaluation of a 16-inch PSGV, which is installed on the HP steam line, is performed according to the fatigue life assessment method described in the ASME B&PVC VIII-2; the method uses the equivalent stress from the elastic stress analysis.