• 한국컴퓨터정보학회논문지
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• 제11권2호
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• pp.131-143
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• 2006

무선통신 기술의 급속한 발전으로 무선 인터넷 서비스가 점차 확대되고 있고 그 중 모바일 실시간 처리가 큰 비중을 차지하고 있다. 모바일 트랜잭션 처리는 낮은 대역폭과 핸드오버, 응답시간 지연 등으로 그것의 활성화를 저해하는 여러 가지 문제점을 지니고 있음에도 불구하고 모바일 컴퓨팅 분야에 다양하게 응용되고 있다. 그래서 모바일 컴퓨팅 환경에서 제한된 대역폭을 효율적으로 사용하고, 병목현상을 개선한 새로운 동시성 제어 기법이 요구된다. 본 논문에서는 모바일 컴퓨팅 환경에서의 동시성 제어 문제를 효과적으로 해결하고 동시에 여러 트랜잭션을 처리하여 병렬성을 증진시키는 낙관적 동시성 기법을 제안하였다. 기존기법과 달리, 제안하는 기법은 같은 세그먼트 내에 다른 데이터를 접근하는 트랜잭션에게 세그먼트를 허용함으로써 불필요한 대기시간을 최소화 할 수 있도록 하여 시스템 처리율을 향상시켰다. 그리고 제안된 동시성 제어 기법의 알고리즘을 제안하였다.

• 한국컴퓨터정보학회:학술대회논문집
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• 한국컴퓨터정보학회 2008년도 제38차 하계학술발표논문집 16권1호
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• pp.99-103
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• 2008

분배시스템에서 완제품에 대한 재고통제 운용전략은 기업들에 있어 많은 관심의 대상이 되어 오고 있으며, 스케일 메리트(scale merit)기대를 위한 소종대량 취급방식은 고객 요구의 다양화로 더 이상 지속하기 힘들게 되었다. 이러한 환경변화에 대응하기 위하여 많은 기업들은 다양한 제품을 취급하는 추세에 있다. 그러나 기업이 고객 요구 다양화에 부응하기에는 많은 비용이 소요된다. 게다가 잔여재고는 진부화 또는 불량재고가 되어 기업에 부담을 가중시킨다. 이러한 비효율적인 문제해결을 위하여 본 연구는 다종소량 취급 방식과 소종소량 취급 방식의 비용비교를 통하여 물류수송비용 및 재고비용 감소의 합리화를 도출하였다.

• 대한지역사회영양학회지
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• 제8권5호
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• pp.744-754
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• 2003

At present, health care industries throughout the world are struggling with the challenges to set up financial structures as cost-effective ways and means of satisfying customer needs for health care services. Many hospitals consign foodservice management to foodservice companies for the purpose of efficiency. The companies taking charge of hospital foodservice are also striving to gain an advantage over keen competitions. This study applied Quality Function Deployment(QFD) to one hospital (which will be shown as $\ulcorner$A hospital$\lrcorner$ below) managed by a contract foodservice company for the purpose of strategy planning to provide sustainable competitive advantage. First of all, this study scanned internal and external environment of $\ulcorner$A hospital$\lrcorner$ by means of a Quality Measurement Tool and a fieldwork study. With the result of environment scanning, this study elicited 20 strategies through SWOT analysis, which were categorized by 4 perspectives such as financial, customer, internal process, learning and growth perspectives. Finally, the priorities of 20 strategies were extracted from QFD methodology. According to the results obtained by applying QFD to $\ulcorner$A hospital$\lrcorner$'s foodservice, the strategies which $\ulcorner$A hospital$\lrcorner$ foodservice was obliged to introduce and implement were : the specialization of Children's hospital foodservice, scientific foodservice management through the standardization of foodservice operations, the maintenance of sanitary quality through sanitary system, the remodeling of facilities, the introduction of new equipment, the prompt and accurate response to customer needs, the development of appropriate patient menus, the provision of competitively priced meals for patient selection, the development of a demand forecast model by considering the characteristics of a children's hospital, improvement of productivity and the reduction of labor costs through the employment of experienced employees based on their seniority.

• 한국응급구조학회지
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• 제11권2호
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• pp.87-101
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• 2007

Health and disease related characteristics of 226 selected by systematic sampling from 452 personal emergency response system(PERS) beneficiaries and actual conditions of using PERS by them are as follows. Over 86% of PERS beneficiaries have not good health conditions and 70.7% of them have chronic diseases. On social supports family was highest as 52.2% and cases having social workers' assistance were 15.2%, but 53 as 23.7% had not visit or call from anyone and showed very low social supports. 86.2% was given PERS within 3years and 79.1% had it by the recommendation from related agencies and 4.0% was by their demand. On wearing it, 78.3% didn't bring it with them and 92% of them answered they were not sick and then it was found that they didn't use it because they had not special emergency. On satisfaction with paging system's operation, 81.3% answered they were satisfied with it, 48.8% used it for 'acute and emergency diseases' and 29.3% called ambulance for 'appointed medical treatment'. Time required for ambulance to arrive at the field was within 10 min. in 87.8% and after 10 min. in 12.2% and emergency service for beneficiaries by fire service was very good. On satisfaction with use of PERS, 85.4% were satisfied with it, 81.9% who requested repair or replacement of radio paging got it back after one or two days of their request and they answered they were satisfied with A/S. 45.5% answered they powered off it because 'they didn't use it' and 12.1% had 'economical reason of phone charge'.

• 한국수소및신에너지학회논문집
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• 제23권4호
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• pp.412-419
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• 2012

Increasing demand for natural gas and higher natural gas prices in the recent decades have led many people to pursue unconventional methods of natural gas production. POSCO-Gwangyang synthetic natural gas (SNG) project was launched in 2010. As the market price of natural gas goes up, the increase of its price gets more sensitive due to the high cost of transportation and liquefaction. This project can make the SNG economically viable. In parallel with this project, KEPCO (Korea Electric Power Corporation) joined in launching the SNG Quality Standard Bureau along with KOGAS (Korea Gas Corporation), POSCO and so on. KEPCO Research Institute is in charge of SNG fueled gas turbine combustion test. In this research, several combustion tests were conducted to find out the effect of hydrogen contents in SNG on gas turbine combustion. The hydrogen in synthetic natural gas did not affect on gas turbine combustion characteristics which are turbine inlet temperature including pattern factor and emission performance. However, flame stable region in ${\Phi}$-Air flow rate map was shifted to the lean condition due to autocatalytic effect of hydrogen.

• 한국항만경제학회지
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• 제26권4호
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• pp.101-121
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• 2010

국내 화물자동차운송시장은 공급과잉이라는 열악한 경영환경에 직면해 있을 뿐만 아니라 화물운송과정에 있어서 심각한 구조적 문제를 안고 있다. 이러한 요인들은 국내 화물자동차운송산업의 경쟁력을 약화시키고 관련산업의 발전을 저해하는 결과를 초래하고 있다. 특히 최근 한국경제의 침체와 화물자동차운임하락 등의 문제는 화물자동차 운수사업자들의 생계를 위협하고 있다. 한국 정부 및 국회는 화물자동차운수사업법의 개정을 통해 이러한 문제를 정책적으로 해결하고자 노력하고 있다. 개정법률안의 핵심적 내용 중의 하나는 화물자동차운송정보망 사용의 의무화이다. 본 논문에서는 화물자동차운송정보망의 구축전략을 개념적으로 제시하고 4가지 수요 시나리오를 가정하여 정보망사업에 대한 경제적타당성 분석을 수행하였다. 분석결과 화물정보망의 구축은 각 화물자동차운송사업자들의 유형별로 전국적 기반하에서 각각 구축하는 것보다는 화물자동차운송사업자들이 공동으로 지역별로 구축하는 것이 보다 효과적으로 나타났다. 이러한 공동 정보망 구축시 투자 타당성은 높은 것으로 나타났다.

• Journal of Magnetics
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• 제21권2호
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• pp.266-272
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• 2016

Transcranial magnetic stimulation devices has been used mainly for diagnostic purposes by measuring the functions of the nervous system rather than for treatment purposes, and has a problem of considerable energy fluctuations per repeated pulse. The majority of strokes are caused by ischemia and result in brain tissue damage, leading to problems of the central nervous system including hemiparesis, dysfunction of language and consciousness, and dysfunction of perception. Control is difficult and the size is large due to the difficulty of digitalizing the energy stored in a capacitor, and there are many heavy devices. In addition, there are many constraints when it is used for a range of purposes such as head and neck diagnosis, treatment and rehabilitation of nerve palsy, muscle strengthening, treatment of urinary incontinence etc. Output stabilization and minimization of the energy variation rate are required as the level of the transcranial magnetic stimulation device is dramatically improved and the demand for therapeutic purposes increases. This study developed a compact, low cost transcranial magnetic stimulation device with minimal energy variation of a high repeated pulse and output stabilization using a real time capacitor charge discharge voltage. Ischemia was induced in male SD rats by closing off the common carotid artery for 5 minutes, after which the blood was re-perfused. In the cerebrum, the number of PARP reactive cells after 24 hours significantly decreased (p < 0.05) in the TMS group compared to the GI group. As a result, TMS showed the greatest effect on necrosis-related PARP immuno-reactive cells 24 hours after ischemia, indicating necrosis inhibition, blocking of neural cell death, and protection of neural cells.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2005년도 추계종합학술대회
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• pp.67-70
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• 2005

최근 해양레저의 수요가 증가하면서 해상 안전과 급변하는 기상환경에 따라 신속하고 체계적인 정보의 제공에 관심이 집중되고 있다. 해상에서 모바일 단말기를 통한 지리정보의 제공에 있어서 전자해도의 사용은 방대한 양의 데이터 정보와 해도표현의 복잡한 처리 방식으로 인하여 국내에서는 PDA 환경에서 구동하는 수준까지 진행되었고, 아직은 선박의 의무적인 항해 장비에 탑재되어 사용되고 있을 뿐이다. 본 논문에서는 기상정보 등의 각종 해양 레저 정보와 전자해도의 이미지 정보를 효율적으로 모바일 휴대폰 단말기에 서비스하기 위하여 제한적인 단말기의 자원 관리와 캐슁 기법을 통한 신속한 정보의 제공, 이미지 변환 및 데이터베이스 구축과 빠른 검색을 위한 색인 관리를 담당하는 서버 시스템을 개발하고자 한다.

• 한국정보통신학회논문지
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• 제17권12호
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• pp.2952-2959
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• 2013

본 논문에서는 국제 통신 프로토콜이 적용된 스마트미터를 개발하였다. 스마트미터는 전력 공급 사업자와의 데이터 교환을 위해 양방향 통신 및 제어 기술, 전기 기기의 등록 및 해제를 위한 통신 프로토콜이 요구된다. 스마트미터의 통신 프로토콜은 미국과 유럽을 중심으로 표준화가 진행되고 있으며, 본 논문에서 제안하는 스마트미터의 통신 프로토콜은 북미방식인 ANSI C12.22 표준을 채택하여 적용하였다. 스마트미터는 또한 전력 사용자에게도 실시간으로 소비 전력 정보와 요금 정보를 제공해야 하며, 사용자는 이 정보를 바탕으로 적절하게 수요반응을 할 수 있어야한다. 본 논문에서는 스마트미터에서 측정되는 전력량이 실시간으로 사용자에게도 보고될 수 있도록 하였으며, IHD(In Home Display)를 윈도우즈 소프트웨어로 구현하여 개발된 스마트미터와의 연동을 실현하였다.

• 한국기후변화학회지
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• 제8권3호
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• pp.265-273
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• 2017

Recently the Paris Climate Change Accord has been officially put into effect, making global efforts to implement Greenhouse Gas (GHG) reductions, and also International environmental regulations in the automotive sector will be further strengthened. The electric vehicle, which minimizes the particulate matter generated by existing internal combustion engine automobiles, is evaluated as a representative eco-friendly automobile. However, charging the battery of an electric vehicle is not fully environment-friendly if it is fueled by electricity that is being generated by fossil fuels as an energy source. The energy generated by the photovoltaic power generation system, which is an infinite clean energy, can be used to charge an electric vehicle's battery. Currently, shortage of charging facilities, time of charging, and high battery prices are the problem of activating the supply of electric vehicles. This study is to build a conjunction between the EVBSS (Electric Vehicle Battery Supply System) and ESS (Energy Storage System), which can quickly supply the photovoltaic charged battery to the required demand. If the charged battery in the Battery Swapping Station (BSS) is swapped swiftly, it will dramatically shorten the waiting time for charging the battery. As a result, if the battery is rented when it is needed, electric vehicles can be sold without the cost of a battery, which accounts for a large portion of the total cost, then the supply of electric vehicles are expected to expand. Furthermore, it will be an important alternative to maneuver climate change by minimizing GHG emissions from internal combustion engine vehicles.