• Vacuum Magazine
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• v.2 no.2
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• pp.12-16
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• 2015

Organic photovoltaics (OPVs) have attracted significant interest in an interdisciplinary research field for the decades as a next-generation photovoltaic device due to their unique advantages. One of requirements for OPVs having high power conversion efficiency is the favorable energy level alignment between the electrode/organic and organic/organic interfaces to manage the exciton dissociation and improve the charge transport. In this review, strategies to enhance the OPV performance by controlling the energy level alignment are discussed. The insertion of an exciton blocking layer leads to the efficient dissociation of photogenerated excitons at the donor/acceptor interface enhancing the short-circuit current density. The choice of a donor having a high ionization energy and an acceptor having a low electron affinity increases the open-circuit voltage. The insertion of an appropriate work function modifier which reduces the charge injection barrier removes the S-kink in current density-voltage characteristics of OPVs and improves the fill factor. This review would give a valuable guide to design the efficient OPV structure.

• KEPCO Journal on Electric Power and Energy
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• v.2 no.1
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• pp.43-47
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• 2016

This system is a diagnosis system that checks whether it causes a partial discharge of a power cable or not. It is to classify normal from abnormal-normal, PD (Partial Discharge) sound through analysis of RLCR (Relative Level Crossing Rate) and spectrogram energy algorithm. Partial discharge diagnostic system has a function that stores PD sound and analyzes the data. The wave shape of PD sound is similar to noise and is systematically generated by partial discharge. Therefore, in this paper, we could discreminate between normal and abnormal case using relative level crossing rate (RLCR) and spectrogram of frequency energy rate.

• Nuclear Engineering and Technology
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• v.35 no.4
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• pp.261-273
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• 2003

The characteristics of the recirculation operation of LMR which are different from the conventional plants such as PWR and fossil fuel plants were investigated using a computer code TSGS developed in this study. For simulating the transient behavior of the steam generation system, a water level control algorithm utilizing digital control hardware features was introduced. By investigation, the function of the recirculation operation was defined, the major features of the operation were found. Also good performance of the level control algorithm was confirmed.

• Nuclear Engineering and Technology
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• v.32 no.5
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• pp.504-513
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• 2000

The adsorption characteristics of methyl iodide generated from the simulated off-gas stream on various adsorbents such as silver ion-exchanged zeolite (AgX), zeocarbon and activated carbon were investigated. An extensive evaluation was made on the optimal silver ion-exchanged level for the effective removal of methyl iodide at temperature up to 38$0^{\circ}C$. The degree of adsorption efficiency of methyl iodide on silver ion-exchanged zeolite is strongly dependent of silver ion-amount and process temperature. The influence of temperature, methyl iodide concentration and silver ion-exchanged level on the adsorption efficiency is closely related to the pore characteristics of adsorbents. It would be facts that the effective silver ion-exchanged level was about 10 wt%, based on the degree of silver utilization for the removal of methyl iodide.

• Journal of Families and Better Life
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• v.8 no.2
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• pp.119-134
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• 1990

The purpose of this study were to investigate; The contact of housewives with governmental public advertisement about the energy conservation, general tendency about the energy conservation consciousness and behavior. For these purposed, a survey was conducted using questionnaires. Data analysis were conducted from 367 housewives with children in Seoul. Used statistical method were Frequency Distribution, percentile, Mean, one Way Anova, t-test, F-test, Pearson's Correlation, Multiple regression Analysis and Path Analysis. Major findings are as follows. 1) Level of public advertisement contact was low. In contrast to , level of energy conservation consciousness, consciousness change, and behavior was adequately high. 2) Statistically significant difference were found in advertisement contact according to the husband's age , Energy conservation consciousness change according to husband's occupation, and energy conservation behavior according to family life cycle. 3) Energy conservation consciousness changes were increased by advertisement contact. Energy conservation behaviors were increased by conservation consciousness and the degree of conservation consciousness change. 4) Governmental public advertisement about the energy conservation has both direct and indirect effect on the energy conservation behavior. From these finds, the following suggestions are made. Governmental effort about the energy conservation advertisement is needed to be activated. And the implications for the future study was need to incorporate the psychological variables in energy conservation study.

• Journal of the Korean Society of Food Science and Nutrition
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• v.12 no.3
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• pp.264-272
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• 1983

In order to investigate the effect of dietary protein and energy on growing female and male rats, Sprague-Dawley 90 female rats and 54 male rats of 3 weeks old weighing approximately 70-80g and 54-75g, respectively, were subjected feeding trials for 8 weeks and then subsequently to metabolic trials for 2 weeks. Three dietary energy levels(3,200, 3,600, 4,000 kcal/kg) were employed and each energy level contained three protein levels (15, 25, 35% of 3600 kcal ME/kg) and three rat levels (10, 20, 40% of 3,600 kcal ME/kg) by addition of an appropriate amount of carbohydrate and the following result were obtained. As the protein level was increasing, digestibilities of dry matter and carbohydrate tended to decrease whereas that of protein was slightly increasing. On the other hand, digestibility of fat was always very high regardless of the level of protein but that tended to be slightly improved as the level of energy or rat increased. The digestibilities of female and male rats tended to be same. The digestibilities of dry matter, crude protein, crude fat and carbohydrate were 83%, 90%, 96% and 93%, respectively, and they were neither affected by protein and energy levels nor observed differently depending upon the sex. Nitrogen retention of female and male rats were best for LPHE ration. In other words, both nitrogen retention was improved as the level of energy increased and the level of protein decreased. The gross energy intake was high at low protein level in female rats and at medium protein level in male rats. That tended to decrease as the level of energy increased in female rats whereas that was not affected by the level of energy in male rats. The metabolic energy efficiency was highest for LPHE ration in female rats and for LPME ration in male rats.

• Asian-Australasian Journal of Animal Sciences
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• v.4 no.4
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• pp.383-393
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• 1991

The present study was carried out to investigate the effect of cimaterol on growth performance, carcass quality and cellular functional activity of broilers as affected by the various protein and energy levels. In starter period (0-21 days) all chicks were fed the basal diet which contained approximately 23 % crude protein and 3200 kcal of metabolizable energy per kg of diet. The cimaterol was added during 22-49 days and during the period of 8th week the cimaterol was withdrawn. In finisher period (22-49 days), a $2{\times}2{\times}3$ factorial arrangement consisting of 2 levels of cimaterol (0 mg/kg, 0.25 mg/kg), 2 levels of protein (19%, 17%) and 3 levels of energy (3200, 2900, 2600 kcal/kg) was used. In the finisher period, the body weight gain and feed efficiency was improved by the supplementation of cimaterol. The high protein and high energy level with supplementation of cimaterol had showed the highest body weight gain and feed efficiency, without significant difference. The administration of cimaterol had no effects on percentage of abdominal fat content, giblet and neck. Eventhough the difference was not significant (p>0.05), carcass yield was improved slightly by the administration of cimaterol. The effect of cimaterol on carcass composition was clearly demonstrated that protein content of broilers was not increased (p>0.05) but fat content decreased significantly (p<0.05). The ultilization of nutrients in experimental diets was not significantly affected by feeding cimaterol compared to control group. The results of in vitro studies with liver and adipose tissue showed that cimaterol increased the lipolytic activities at 19% protein level whereas at 17% protein level this effect was variable. Lipogenic activities in liver and adipose tissue were not affected with the administration of cimaterol but the activities increased as energy decreased, particularly in liver tissue. In cell studies with acinar culture of liver tissues, cimaterol had no effect on protein synthetic activity but the parameter was increased at higher level of dietary protein and energy. Protein secretion in liver was increased by the supplementation of cimaterol. In addition, at high protein level the protein secretion was increased and has shown the highest values at medium energy level.

• Journal of the Korean Society for Railway
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• v.9 no.1 s.32
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• pp.1-6
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• 2006

The purpose of this study is to calculate transmission loss of the high speed railway's wall section accurately. Transmission loss measurement of ideal case i.e. the wall in the laboratory condition was carried out in first, which results were compared with those by statistical energy method. Transmission loss values of high speed railway calculated out by experimental method are compared with those from closed form solution. Commercial statistical energy analysis was also used to predict the outside pressure level using those measured transmission loss values. Simple SEA model could estimate reasonable exterior sound pressure level.

• Journal of Electrical Engineering and Technology
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• v.13 no.1
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• pp.326-332
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• 2018

In this paper, the design process and the control method of the power conversion system (PCS) that consists of a bidirectional DC-DC converter and a 3-level T-type inverter for an energy storage system is presented. Especially the design method of the output LCL filter for a 3-lvel T-type inverter without complex mathematical process are proposed. The validity of the control method and design process in this paper are verified through simulation and experimental analysis.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 1999.11a
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• pp.143-148
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• 1999

A distributed real-time system that is being wed now is usually divided into three level : higher level, middle level, and lower level. The higher level network is usually called an information network, the middle level is called a control network, and the lower level is called a field network or a divice network. This dissertation suggests and implements a middle level network which is called PICNET-NP (Plant Implementation and Control Network for Nuclear Power Plant). PICNET-NP is based partly on IEEE 802.4 token-passing bus access method and partly on IEEE 802.3 physical layer. For this purpose a new interface, a physical layer service translator, is introduced. A control network using this method is implemented and applied to a distributed real-time system.