• Journal of the Korean Electrochemical Society
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• v.12 no.4
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• pp.329-334
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• 2009

This study is to develop a fuel cell system applicable to an in situ NMR (Nuclear magnetic resonance) diagnosis. The in situ NMR can be used in real time monitoring of various reactions occurring in the fuel cell, such as oxidation of fuel, reduction of oxygen, transport phenomena, and component degradation. The fuel cell for this purpose is, however, to be operated in a specifically designed tubular shape toroid cavity detector (TCD), which constrains the fuel cell to have a tubular shape. This may cause difficulties in effective mass transport of reactants/products and uniform distribution of assembly pressure. Therefore, a new flow field designed in a particular way is necessary to enhance the mass transport in the tubular fuel cell. In this study, a tubular-shaped close-type flow field made of non-magnetic material is developed. With this flow field, oxygen is effectively delivered to the cathode surface and the produced water is readily removed from the membrane-electrode assembly to prevent flooding. The resulting DMFC (direct methanol fuel cell) outperforms the open-type flow field and exhibits $36\;mW/cm^2$ even at room temperature.

• Journal of the Microelectronics and Packaging Society
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• v.14 no.2 s.43
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• pp.17-21
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• 2007

Dense and periodic arrays of holes and Si nano dots were fabricated on silicon substrate. The nanopatterned holes were approximately $15{\sim}40nm$ wide, 40 nm deep and $40{\sim}80\;nm$ apart. To obtain nano-size patterns, self?assembling diblock copolymer were used to produce layer of hexagonaly ordered parallel cylinders of polymethylmethacrylate (PMMA) in polystyrene(PS) matrix. The PMMA cylinders were degraded and removed with acetic acid rinse to produce a PS. $100\;{\AA}-thick$ Au thin film was deposited by using e-beam evaporator. PS template was removed by lift-off process. Arrays of Au nano dots were transferred by using Fluorine-based reactive ion etching(RE). Au nano dots were removed by sulfuric acid. Si nano dots size and height were $30{\sim}70\;nm$ and $10{\sim}20\;nm$ respectively.

• Korean Journal of Social Welfare
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• v.54
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• pp.177-201
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• 2003

Gambling is prevailing in our society and the family problems of gamblers are also serious. In order to reduce the problems of gamblers and their families, the basic research on gambling would be the first step. In light of this, this study is a survey which has two objectives: to grasp the overall conditions of gambling and the proportion of pathological gamblers; to find the differences between the pathological gamblers' group and the general group in terms of various aspects of family relations in Choongchung area. The findings of this study is as follows, The respondents tend to gamble most with korean playing cards, either in winter or regardless of seasons. They tend to gamble most with family members, relatives, or friends. About 20% of them gamble more often than once a month, and 60% started gambling in their twenties or thirties. The proportion of pathological gamblers was found to be 11.6% of the sample of this study, with men and rural area residents to be significantly more than women and urban area residents. In the various aspects of family lives, such as marital satisfaction, family relations, family violence, family history of addiction, how to spend leisure time with family, it was found that the pathological gamblers' group has significantly more problems than the general group. On the basis of the above findings, the suggestions were made as follows. Firstly, the counter plan to gambling is necessary in the rural area, especially in winter time. secondly, positive leisure activities which substitute gambling needs to be developed, especially for men. Thirdly, family education and family therapy Program is required for the pathological gamblers and their families. Fourthly, governmental policy is necessary for the budget to prevent and treat gambling problems.

• Journal of the Korean Society of Marine Environment & Safety
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• v.22 no.5
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• pp.417-422
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• 2016

Aids to Navigation (AtoN) are marine traffic facilities to improve the safety and efficiency of shipping. "New Dangers" should be appropriately marked using lateral, cardinal or isolated danger marks or by using an Emergency Wreck Marking Buoy. However, Emergency Wreck Marking Buoys are difficult to implement in terms of speed and accuracy of installation. In the case of sinking accidents, it is often difficult to immediately install an Emergency Wreck Marking Buoy because of weather conditions, the marine environment or accident positioning. This study concerns Auto-Releasing Emergency Wreck Marking Buoys, which should be installed in all vessel for safe marine navigation and efficient maritime transport with reference to the Maritime Buoyage System (MBS). Auto-Releasing Emergency Wreck Marking Buoys include an auto-release unit, auto reel chain and auto lighting lantern. These buoys can be automatically released from the deck of a vessel and will float in the water for quick installation at the scene of an accident, even in the case of sinking accidents. Auto-Releasing New Mark Buoys are expected to reduce to installation process, prevent secondary accidents by the risk of navigation and be search and rescue rapidly.

• Journal of Korean Home Economics Education Association
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• v.31 no.2
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• pp.67-77
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• 2019

The purpose of this study was to identify significant differences in dietary guidelines, emotional intelligence, resilience and violence according to the frequency of family meals for middle school students in Daegu. To achieve the purpose of this study, 241 data collected through self-administered questionnaires were analyzed. The collected data were analyzed using the SPSS (v25.0) program for frequency, percentage, standard deviation, reliability, one-way ANOVA and Duncan comparison. The results of this study were as follows. There was a significant difference in the level of the dietary guidelines practice, emotional intelligence and resilience according to the frequency of family meals of middle school students. Implications and suggestions based on the results of this study were as follows. First, family meal frequency is significantly related to middle school students' dietary guidelines practice, emotional intelligence, and resilience (p<0.05). Accordingly, personal efforts and social and institutional arrangements are required to increase the family meal frequency. Second, some of the core competences required in the 2015 revised curriculum were consistent with sub-areas of emotional intelligence and resilience, which can be predicted by the results that family meal experience of middle school students is also related to the development of core competences. In conclusion, increasing family meal frequency is important considering the trend of education, and is required for personality education.

• Journal of Life Science
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• v.22 no.8
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• pp.999-1008
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• 2012

The circadian clock is a self-sustaining 24-hour timekeeper that allows organisms to anticipate daily-changing environmental time cues. Circadian clock genes are regulated by a transcriptional-translational feedback loop. In Arabidopsis, LATE ELONGATED HYPOCOTYL (LHY) and CIRCADIAN CLOCK-ASSOCIATED 1 (CCA1) transcripts are highly expressed in the morning. Translated LHY and CCA1 proteins repress the expression of the TIMING OF CAB EXPRESSION 1 (TOC1) transcripts, which peaks in the evening. The TOC1 protein elevates the expression of the LHY and CCA1 transcripts, forming a negative feedback loop that is believed to constitute the oscillatory mechanism of the clock. In mammals, the transcription factor protein CLOCK, which is a central component of the circadian clock, was reported to have an intrinsic histone acetyltransferase (HAT) activity, suggesting that histone acetylation is important for core clock mechanisms. However, little is known about the components necessary for the histone acetylation of the Arabidopsis clock-related genes. Here, I report that DET1 (De-Etiolated1) functions as a negative regulator of a key component of the Arabidopsis circadian clock gene LHY in constant dark phases (DD) and is required for the down-regulation of LHY expression through the acetylation of histone 3 (H3Ac). However, the HATs directly responsible for the acetylation of H3 within LHY chromatin need to be identified, and a link connecting the HATs and DET1 protein is still absent.

• Proceedings of the Korea Society for Industrial Systems Conference
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• 2000.11a
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• pp.231-231
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• 2000

인터넷기업들은 불과 몇 달 전만 해도 수수께끼로 가득 찬 요지경이었다. 매출액은 늘어났지만 더 많은 손실이 발생했고, 엄청난 적자와는 정반대로 주가는 연일 상승곡선을 그리고 있었다. 오히려 손실을 줄이는 방안을 발표하면 주가가 떨어지는 기현상마저 보여 구경제의 질서에 익숙해 있던 투자자들이나 경영자들을 혼란스럽게 만들고 있다. 그런데 이처럼 높게 평가되던 인터넷 기업들의 주가가 최근에 들어 폭락하고 있다. eToys의 경우 주가가 최고치 였던 ＄86에서 94% 폭락한 ＄4.75에 거래되었고, CDNow는 83%, Buy.com은 81% 등 주요 온라인 업체들의 주가가 80% 이상 하락하였으며 그 외의 적지 않은 인터넷 기업들의 주가 역시 전성기에 비해 90-95%까지 폭락하였다. 이러한 이유로 최근 인터넷기업들의 정확한 가치평가를 하기 위한 연구들이 시도되고 있으며, 이러한 시도 중 비교적 객관적인 정보인 재무정보들을 이용하기 위한 연구들도 있다. 하지만 아직까지는 우리나라의 재무제표들이 제공하는 정보들이 부족하고 IMF이후 비정상적인 주가 등으로 인하여 실증하는데 어려움이 따르고 있다. 또한 인터넷 기업들은 전술한 바와 같이 기존 오프라인상의 제조업형태의 기업들처럼 일반적인 재무제표분석을 통한 가치평가에 어려움을 겪고 있다. 하지만 인터넷을 기반으로 한 디지털 경제에서도 오프라인기업에서와 똑같은 현상이 발생한다는 사실을 간과해서는 안 된다. 현금지출이 도달 가능한 현금유입의 수준을 넘어선다면 결국 도산하는 것은 인터넷기업들도 마찬가지이다. 현재 어떤 기업에 투자하는 것은 그 기업의 미래 현금흐름을 구매하고자 하는 것이다. 따라서 미래의 현금흐름이 커질수록 그 기업의 가치는 상승하게 된다. 현금흐름 분석이 특히 중요한 이유는 기업의 미래 현금흐름을 기업의 타인자본비용과 자기자본비용의 조합인 기회자본비용으로 할인함으로써 현재의 기업가치를 구할 수 있기 때문이다. 이처럼 기업이 영업활동이나 투자활동을 통해 현금을 창출하고 소비하는 경향은 해당 비즈니스 모델의 성격을 규정하는 자료도로 이용될 수 있다. 또한 최근 인터넷기업들의 부도가 발생하고 있는데, 기업의 부실원인이 어떤 것이든 사회전체의 생산력의 감소, 실업의 증가, 채권자 및 주주의 부의 감소, 심리적 불안으로 인한 경제활동의 위축, 기업 노하우의 소멸, 대외적 신용도의 하락 등과 같은 사회적·경제적 파급효과는 대단히 크다. 이상과 같은 기업부실의 효과를 고려할 때 부실기업을 미리 예측하는 일종의 조기경보장치를 갖는다는 것은 중요한 일이다. 현금흐름정보를 이용하여 기업의 부실을 예측하면 기업의 부실징후를 파악하는데 그치지 않고 부실의 원인을 파악하고 이에 대한 대응 전략을 수립하며 그 결과를 측정하는데 활용될 수도 있다. 따라서 본 연구에서는 기업의 부도예측 정보 중 현금흐름정보를 통하여 '인터넷기업의 미래 현금흐름측정, 부도예측신호효과, 부실원인파악, 비즈니스 모델의 성격규정 등을 할 수 있는가'를 검증하려고 한다.

• Proceedings of the Korea Society for Industrial Systems Conference
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• 2000.11a
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• pp.575-585
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• 2000

본 사업은 1994년부터 1996년까지 3년 간 시범사업으로 추진된 지역정보화 사업의 과제인 창원/마산 지역정보 유통망 구축사업을 확대 발전시키고 시스템 운영의 효율화를 도모하고자 DB를 통합하여 확대 재 구축함으로써 전자상거래 기반의 인터넷을 통한 웹 정보 이용 활성화 차원에서 추진되었다. 기 구축되었던 $\ulcorner$창원/마산 지역정보유통망 구축사업$\lrcorner$은 정보화를 통한 지역경제 발전에 일익을 담당하고자 관. 산. 연이 참여한 지역정보화 사업이다. 이러한 창원/마산지역 산업체에 대한 지원효과를 이번에 확대하여 그 동안 Multimedia, Graphics, Web 등 정보화 환경이 크게 변화, 발전됨에 따라 현실적이며 현장적용형 패키지의 개발 지원이 대두된 $\ulcorner$경남지역 정보화확산사업$\lrcorner$은 연구개발정보센터와 창원시, 진해시, 한국기계연구원이 매칭 펀드에 의한 대응자금으로 구축한 시스템이다. 정보수집대상은 경남지역에 소재하고 있는 20개 산업단지 3,700여 입주기업을 정보수집요원이 직접 방문하여 현장에서 필요로 하는 요구정보를 반영하였다. 신규로 구축한 정보는 산업기반 기업체기본정보 DB 및 기업 기술개발 현장적용형 기술정보 패키지정보를 중심으로 구축하였으며, 인터넷 활용교육을 통한 동종 업종간 정보교류체제 구축하였다. 특히 Cyber Market을 구현하기 위해 1,200여건의 기업체정보 및 제조상품 DB를 응용한 제품 Mall 데이터베이스를 구축하였다. 본 사업을 통하여 경남지역 산업단지에 입주한 기업체의 정보 활용을 극대화하여 지역경제 발전에 기여함과 동시에 국내 지역정보화 시범모델로서 위상을 확립하고자 한다.을 기업의 타인자본비용과 자기자본비용의 조합인 기회자본비용으로 할인함으로써 현재의 기업가치를 구할 수 있기 때문이다. 이처럼 기업이 영업활동이나 투자활동을 통해 현금을 창출하고 소비하는 경향은 해당 비즈니스 모델의 성격을 규정하는 자료도로 이용될 수 있다. 또한 최근 인터넷기업들의 부도가 발생하고 있는데, 기업의 부실원인이 어떤 것이든 사회전체의 생산력의 감소, 실업의 증가, 채권자 및 주주의 부의 감소, 심리적 불안으로 인한 경제활동의 위축, 기업 노하우의 소멸, 대외적 신용도의 하락 등과 같은 사회적·경제적 파급효과는 대단히 크다. 이상과 같은 기업부실의 효과를 고려할 때 부실기업을 미리 예측하는 일종의 조기경보장치를 갖는다는 것은 중요한 일이다. 현금흐름정보를 이용하여 기업의 부실을 예측하면 기업의 부실징후를 파악하는데 그치지 않고 부실의 원인을 파악하고 이에 대한 대응 전략을 수립하며 그 결과를 측정하는데 활용될 수도 있다. 따라서 본 연구에서는 기업의 부도예측 정보 중 현금흐름정보를 통하여 '인터넷기업의 미래 현금흐름측정, 부도예측신호효과, 부실원인파악, 비즈니스 모델의 성격규정 등을 할 수 있는가'를 검증하려고 한다. 협력체계 확립, ${\circled}3$ 전문인력 확보 및 인력구성 조정, 그리고 ${\circled}4$ 방문보건사업의 강화 등이다., 대사(代謝)와 관계(關係)있음을 시사(示唆)해 주고 있다.ble nutrient (TDN) was highest in booting stage (59.7%); however no significant difference was found among other stages. The concentrations of Ca and P were not different

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.40 no.4
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• pp.316-329
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• 2012

In this paper, optimum design process of ICP (Inductively Coupled Plasma) torch, which has been used widely in aerospace application, such as supersonic plasma wind tunnel, is presented. For this purpose, the behaviors of equivalent circuit parameters (equivalent resistance and inductance, coupling efficiency) were investigated according to the variations of torch design parameters (frequency, $f$, confinement tube radius, $R$ and coil turn numbers, $N$) in the basis of analytical and numerical MHD (Magneto Hydro-Dynamics) models combined with electrical circuit theory. From the results, it is found that equivalent resistance is increased with the increase of $f$ values but vice versa for equivalent inductance. For elevated values of $R$ and $N$, however, both parameters tend to increase. Based on these observations, ICP torch with a power level of 10 kW can be optimized at the design ranges of $f$=4~6 MHz, $R$=17~25 mm and $N$=3~4 to maximize the electrical coupling efficiency, which is the ratio of equivalent resistance to equivalent inductance.

• Journal of Biomedical Engineering Research
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• v.16 no.4
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• pp.507-516
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• 1995

The nonstationary identifier in the DCT domain is suggested in this study for the identification of AR parameters of above-lesion upper-trunk electromyographic (EMG) signals as a means of developing a reliable real time signal to control functional electrical stimulation (FES) in paraplegics to enable primitive walking. As paraplegic shifts his posture from one attitude to another, there is transition period where the signal is clearly nonstationary. Also as muscle fatigues, nonstationarities become more prevalent even during stable postures. So, it requires a develpment of time varying nonstationary EMG signal identifier. In this paper, time varying nonstationary EMG signals are transformed into DCT domain and the transformed EMG signals are modeled and analyzed in the transform domain. In the DCT domain, we verified reduction of condition number and increment of the smallest eigenvalue of input correlation matrix that influences numerical properties and mean square error were compared with SLS algorithm, and the proposed algorithm is implemented using IMS T-805 parallel processing computer for real time application.