• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.30 no.3
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• pp.143-148
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• 2018

In this study the performance and humidity variation for 2 unit cells connected in series were experimentally measured. The relative flow direction of hydrogen and air was changed from parallel flow to counter flow. Internal humidity distribution was then measured by 5 embedded sensors on each channel. In all experimental conditions, the former unit cell showed a better performance and the gap is noted to be higher when counter flow is applied. The performance was noted to be higher at high humidification case in the parallel flow. However, in the counter flow, the difference of performance according to the humidification is negligible. Hydrogen and air are discharged from the PEMFC unsaturated with water vapor at parallel flow/low humidification condition, which explains lower performance of the PEMFC than other conditions. The humidities in hydrogen and air streams of counter flow were noted to increase rapidly even at low humidification condition and the consequential even hydration of membrane is the reason of higher performance.

• Journal of the Korean Home Economics Association
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• v.20 no.4
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• pp.133-142
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• 1982

The Consumer Education is one of the rapidly raised problems in the process of recent Economic Growth. As the Society and its economy changes into Oligopoly, the nature and the scope of the Consumer Education also changes. However, We don't have an institutional, systematic education of consumers. Even the basic concepts of Consumer Education has not yet been established, because it is in an infant state. Thus, the aim of this paper is to establish the fundermental concepts of Consumer Education and to help settlement of the direction of Consumer Education. The conclusions are as following: First, Consumers as the objects of Consumer Education are limited to the Ultimate-Consumer; and they can divided into three groups-Individual Consumer, Consumer-Group, the Consuming Masses. Now were have to deal with not only the concept of Ultimate Consumer which limited to the Consumer, but deal with the realistic problems involving Citizens and Livers. Second, Consumer Education is systematic educational activity in order that Consumers can assume an subjective behavior for the purpose of improvement and support of their own rights in society. Third, Consumer Education which enforced Consumers' Cooperative Society and Goods Test is the movements of systematic resistance of consumers. The former aims at Economic Equilibrium, while the latter Informative Equilibrium. so, the two movements should channel the direction of Consumer Education in order to realize the Equilibrium.

• Journal of Oriental Neuropsychiatry
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• v.3 no.2
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• pp.97-106
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• 1992

The literature which was written about manual technique of 'Four method of conducting the Qi(氣)'suggest the following results. 1. Four method of conducting the Qi(氣) is a total method based on the basic manual method, lifing and thrusting, twisting and rotating(捻轉), timing the insertion and withdrawal(呼吸) ect. 2) Cheongryongphami method(靑龍擺尾法) come to understanding channels and conducting and Qi(氣), Paekhoyodu method(白虎搖頭法) using a channels understanding and Qi(氣) introducing, Changkuthamhyeol method(蒼龜探穴法) using a channels understanding, Ceokpongyeongweon method(赤鳳迎源法) using a collaterals understanding. 3) Cheongryongphami(靑龍擺尾) and Changkuthamhyeol method(蒼龜探穴法) were used on disease like insufficiency symptom-complex(盧證), Paekhoyodu(白虎搖頭) and Ceokpongyeongweon method(赤鳳迎源法) were used on excessivess symptom-complex(實證) of pathogenic factors selectively. But all of them often used on C.V.A. 4) The Yang Channel's points, under the elbow and knee point, are often used as points which are used in "Four method of conducting the Qi(氣), and the Yin, Ren(任) Du(督) channels are used less than the former. 5) The manual techniques of 'Four method of conducting the Qi(氣)' are often used in clinically. "Four method of conducting the Qi(氣)"has been studies as above, but there weren't a lot of literature which is about total manual technique of acupuncture. So there is a need study about it.

• Journal of Korea Water Resources Association
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• v.48 no.4
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• pp.291-298
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• 2015

The aim of this study is that a theoretical formula for estimating the one-dimensional longitudinal dispersion coefficient is derived based on a transverse distribution equation for the depth averaged stream-wise velocity in open channel. In "Part I. Theoretical equation for stream-wise velocity" which is the former volume of this article, the velocity distribution equation is derived analytically based on the Shiono-Knight Model (SKM). And then incorporating the velocity distribution equation into a triple integral formula which was proposed by Fischer (1968), the one-dimensional longitudinal dispersion coefficient can be derived theoretically in "Part II. Longitudinal dispersion coefficient" which is the latter volume of this article. SKM has presented an analytical solution to the Navier-Stokes equation to describe the transverse variations, and originally been applied to straight and nearly straight compound channel. In order to use SKM in modeling non-prismatic and meandering channels, the shape of cross-section is regarded as a triangle in this study. The analytical solution for the velocity distribution is verified using Manning's equation and applied to velocity data measured at natural streams. Although the velocity equation developed in this study do not agree well with measured data case by case, the equation has a merit that the velocity distribution can be calculated only using geometric data including Manning's roughness coefficient without any measured velocity data.

• Korean Journal of Optics and Photonics
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• v.35 no.3
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• pp.107-114
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• 2024

In this study, the feasibility of using the covariance-matrix-adaptation-evolution-strategy (CMA-ES) algorithm in a multichannel coherent-beam-combining (CBC) system was experimentally verified. We constructed a multichannel CBC system utilizing a spatial light modulator (SLM) as a multichannel phase-modulator array, along with a coherent light source at 635 nm, implemented the stochastic-parallel-gradient-descent (SPGD) and CMA-ES algorithms on it, and compared their performances. In particular, we evaluated the characteristics of the CMA-ES and SPGD algorithms in the CBC system in both 16-channel rectangular and 19-channel honeycomb formats. The results of the evaluation showed that the performances of the two algorithms were similar on average, under the given conditions; However, it was verified that under the given conditions the CMA-ES algorithm was able to operate with more stable performance than the SPGD algorithm, as the former had less operational variation with the initial phase setting than the latter. It is emphasized that this study is the first proof-of-principle demonstration of the CMA-ES phase-control algorithm in a multichannel CBC system, to the best of our knowledge, and is expected to be useful for future experimental studies of the effects of additional channel-number increments, or external-phase-noise effects, in multichannel CBC systems based on the CMA-ES phase-control algorithm.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.36 no.1
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• pp.54-59
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• 2000

This paper presents a control system that uses a fuzzy algorithm in controlling the depth of a model midwater trawl net, and experimental results carried out in the circulating water channel by using a model trawl winch system.The fuzzy controller calculates the length of the warp to be changed, based on the depth error between the desired depth and actual depth of the model trawl net and the ratio of change in the depth error. The error and the error change are calculated every sampling time. Then the control input, i.e. desirable length of the warp, is determined by inference from the linguistic control rules which an experienced captain or navigator uses in controlling the depth of the trawl winch controller and the length of the warp is changed. Two kinds of fuzzy control rules were tested, one was obtained from the actual operations used by a skilled skipper or navigator, and the other was a modified from the former by considering the hydrodynamic characteristics of the model trawl system.Two kinds of fuzzy control were tested, one was obtained fro the actual operations used by a skilled skipper or navigator, and the other was a modified from the former by considering the hydrodynamic characteristics of the model trawl system.The results of these model experiments indicate that the proposed fuzzy controllers rapidly follow the desired depth without steady-state error although the desired depth was given in one step, and show robustness properties against changes in the parameters such as the change of the towing sped. Especially, a modified rule shows smaller depth fluctuations and faster setting times than those obtained by a field oriented rule.

• The Journal of the Korea Contents Association
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• v.17 no.1
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• pp.567-584
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• 2017

This study investigated formats and structure of meanings for the TV talk shows with North Korean defectors. The authors selected of Channel A and of TV Chosun as research subjects. As results of this study, it was found that the former dealt with heavy issues about North Korea, expressed positive perspectives on North Korea and fantasic expectations about South Korea, and produced superior dicourse of South Korea. On the other hand, the latter one dealt with light and sensational items about North Korea, employed dialogues about critics and disappointments on South Korea, and produced problematic discourse about South Korea. The former produced a kind of converged discourse structure to create superior ideology of South Korea, while the latter produced a kind of dichotomous discourse structure to create frustrating ideology. In short, through this study, it turned out that North Korean defectors suffered from their confused identities, unclear self identities, and minority positions in the South Korean society.

• Nuclear Engineering and Technology
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• v.18 no.3
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• pp.200-208
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• 1986

The loss of coolant accident based on a double-ended cold leg break is analyzed with the discharge coefficient (Ca) of 0.4. This analysis covers the whole transient period from the start of depressurization to the complete refilling of the core by using RELAP4/MOD6-EM and RELAP4/ MOD6-HOT CHANNEL for the system thermal-hydraulics and the fuel performance during the blowdown phase respectively, and RELAP4/MOD6-FLOOD and TOODEE2 during the reflood phase. A simple analytical method has been developed to account for the lower plenum filling by approximating steam-water countercurrent flows and superheated wall effects at the downcomer during the refill period. Based on the informations. at the time of EOB (end-of-bypass), the refill duration time and the initial reflooding temperature were estimated and compared with the results from the RELAP4/MOD6, resulting in a good agreement. In addition, some parametric studies on the EOB were performed. The form loss coefficient between upper head and upper downcomer was found to be sensitive to the occurrence of the spurious EOB. Appropriate form loss coefficients should be taken into account to avoid the flow oscillations at the downcomer. The analyses with the six and three volume core nodalizations, respectively, show much similar trends in the system thermal-hydraulic performance, but the former case is recommended to obtain good results.

• Korean Journal of Cognitive Science
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• v.23 no.4
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• pp.425-455
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• 2012

Multi-dimensional verbal short-term memory mechanisms are largely divided into the phonological channel and the lexical-semantic channel. The former is called phonological short-term memory and the latter is called semantic short-term memory. Phonological short-term memory is further segmented into the phonological input buffer and the phonological output buffer. In this study, the language performance of each of three patients with similar levels of conduction aphasia was analyzed in terms of multi-dimensional verbal short-term memory. To this end, three patients with conduction aphasia were instructed to perform four different aspects of language tasks that are spontaneous speaking, repetition, spontaneous writing, and dictation in both word and sentence level. Moreover, the patients' phonological memories and semantic short-term memories were evaluated using digit span tests and verbal learning tests. As a result, the three subjects exhibited various types of performances and error responses in the four aspects of language tests, and the short-term memory tests also did not produce identical results. The language performance of three patients with conduction aphasia can be explained according to whether the defects occurred in the semantic short-term memory, phonological input buffer and/or phonological output buffer. In this study, the relations between language and multi-dimensional verbal short-term memory were discussed based on the results of language tests and short-term memory tests in patients with conduction aphasia.

• Korean journal of communication and information
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• v.31
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• pp.51-84
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• 2005

The purpose of this paper is to investigate characteristics of active information and opinion giver in the interactive-public communication space of internet. More specifically, this study explores that the active information and opinion giver have the same traits with opinion leader, which are personal attributes (topic involvement and individuation), social activity, source of information and influentials, and socio-demographic attributes. The research consisted of a questionnaire, which was administered using e-mail, and 175 replies were returned. The results show that higher activity of sending information and opinion is associated with characteristics of opinion leader. First, It was found that higher activity group in sending information and opinion have higher degree of topic involvement and individuation than lower group. Second, the former is more active behavior than the latter in social activity. Third, it was examined that behaviors of sending and giving information and opinion with interpersonal communication channel was connected with those of the interactive-public communication space in internet. Also, the result of analysis with mass communication channel was found the distinction in three different kinds of magazines which is related with specific media. Finally, characteristics of socio-demography were not different between two group, with the exception of gender.