• 제목/요약/키워드: time availability

검색결과 1,294건 처리시간 0.028초

무기체계 RAM 향상방안 연구 (A Study on the Improvement of RAM for Weapon System)

  • 허동구;최석철
    • 한국국방경영분석학회지
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    • 제27권1호
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    • pp.58-72
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    • 2001
  • This research deals with the weapon system RAM which is the reliability, availability and maintainability for weapon systems. This weapon system RAM is one of very important factors because it is related to the life cycle cost and combat readiness of weapon systems. Therefore, in this research we introduce the weapon system RAM and analyze the problems of weapon system RAM management during system life cycle including acquisition period. Finally we suggest an alternative to improve the weapon system RAM in various agencies which are the department of defense and army headquarter level, etc., in the process of defense acquisition.

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소프트웨어 재활기법에 기반한 주-여분 서버 시스템의 작업전이 시간 분석 (Switchover Time Analysis of Primary-Backup Server Systems Based on Software Rejuvenation)

  • 이재성;박기진;김성수
    • 정보처리학회논문지A
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    • 제8A권2호
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    • pp.81-90
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    • 2001
  • 인터넷의 급속한 확산으로 인하여, 컴퓨터 시스템의 규모 및 복잡도가 점차 증가하고 있으며, 컴퓨터 시스템에 대한 높은 수준의 가용도 요구 조건을 충족시키기 위해, 하드웨어적.소프트웨어적 결함 허용 기법에 대한 연구가 활발하다. 소프트웨어 재활 기법은 서버에 탑재된 소프트웨어의 장시간 가동에 따른 소프트웨어 노화 현상을 다루고 있으며, 서버에서 실행중인 소프트웨어의 수행을 고의적으로 멈춘 후에 결함 발생 가능성이 낮은 초기 상태에서 이를 다시 가동시키는 소프트웨어적 결함 예방 방법의 일종이라 볼 수 있다. 본 연구에서는 주-여분 서버 시스템에서의 작업전이 시간이 소프트웨어 재활에 미치는 영향을 연구하였으며, 가용도 분석을 통해서 작업전이 시간이 재활 정책을 결정함에 있어서 중요한 요소임을 발견하였다.

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무선 ATM LAN 시스템에서 이동 단말에 의한 핸드오버 제어 기법 (Handover Control Scheme Initiated by the Mobile Terminal in Wireless ATM LAN System)

  • 박남훈;김영선;최준균;감상하
    • 한국정보처리학회논문지
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    • 제7권4호
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    • pp.1236-1245
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    • 2000
  • This paper propose a novel scheme, called Mobiel Terminal Initiated Scheme(MTIS), in which mobile terminal initiates the backward handover by sending handover request message with the list of target radio ports. In this scheme, the old ATM switch suporting end-user mobility, denoted by EMAS\ulcorner, checks whether each EMAS\ulcorner, managing the target radio port, has its available resources. If it has, the EMAS\ulcorner performs the path rerouting between CrossOver Switch (COS) and itself after deciding the most suitable target radio port. Therefore, the MT initiates the handover after deciding the most suitable target radio port through the beacon signal of Wireless Access Point (WAP). The EMAS\ulcorner have only to check the resource availability of the target radio port. It is no need to waste time to decide the suitable target radio port. Also, once receiving the request of the resource availability, the EMAS\ulcorner can reduce the rerouting delay time due to perform the path rerouting to the COS. In comparison with that of the ATM-Forum procedure, our proposed MTIS handover delay time reduced 14~21%, and end-to-end transfer delay time reduced 2~9%, as a result of the simulation.

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청소년의 음주·흡연에 따른 구강지식평가 및 구강보건교육의 필요성에 관한 연구 (Study of necessity of teenagers' drinking, mouth knowledge estimation by smoking and dental health education)

  • 최윤화;지윤정
    • 한국치위생학회지
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    • 제8권3호
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    • pp.85-98
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    • 2008
  • This study is to enforce to ready basic data of effective dental education program and no smoking and no drinking program for high school students who do smoking and drinking, executed investigation by own recording way using smoking and questionnaire consisted of actual conditions and caries prevention awareness and dental health knowledge degree of drinking to some man high school. Analyzes result that total 487 people respond in SPSS WIN 13.0 programs and got following sequence. Result of this study is as following. 1. Mans high school students had more students who do not than a drinking student and main current received most soju. Third-year student appeared by thing which receive a lot of soju than 1 or 2 class student but different other difference was not seen by class. 2. Mans high school students had more students who do not than a smoking student and a student who smoke more than 3 years was the most. I can know was old since third-year student smokes than 1 or 2 class student. 3. It was not difference that keep in mind by drinking, smoking availability although there were many students who recognize that all of the on-time dental medical examination, sugar intake limitation, fluorine inclusion toothpaste, teeth fluorine application are seldom effective on caries prevention. 4. Recognized that right brushing is effective relatively on caries prevention. I was shown difference that recognized that righter brushing is effective on bad tooth courtesy call than a student who a student who do not smoke does, and keeps in mind according to smoking availability ($x^2$=6.78, p<0.05). 5. I knew best about question of 'A caries may not treat if is painless' among that question ask knowledge for a caries, and appeared by thing which do not know best about question of 'Know that method that supply fluorine in water'. 6. A student who do not drink general dental know-how for a caries was high knowledge degree for a caries than a drunk student but it was no difference that keep in mind by drinking availability. Also, a student who do not smoke by smoking availability was high knowledge degree for a caries than a done student but difference that keep in mind statistically was not seen. 7. It was no difference that keep in mind by drinking availability, but a student who do not smoke by smoking availability was high relation knowledge degree with food and a caries than a smoked student, and I was shown difference that keep in mind according to smoking availability(t=-2.03, p<0.05). 8. Awareness and synthetic estimation degree of knowledge degree a student who do not smoke than a smoked student mouth knowledge degree high, and I was shown difference that keep in mind according to smoking availability(t=-2.03, p<0.05). When see as result such as singularity, family, school, all social institutions may have to help by national business coming and try so that can become national business based on special know-how for development of effective and epoch-making education program as quickly as possible.

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연구개발 단계에서 성취 가용도를 고려한 최적 수리횟수 결정모델에 관한 연구 (Determination of an Optimal Repair Number with Achieved Availability Constraint at RND Stage)

  • 이재원;이계경;나인성;박명규
    • 대한안전경영과학회지
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    • 제10권3호
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    • pp.89-98
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    • 2008
  • A preventive maintenance model, caller FNBM($\alpha$, $\delta$, $\gamma$)model, is proposed to decide an optimal repair number under achieved availability requirements(r) along with taking two types of failures (repairable or irrepairable) into account. In this model, the current system is replaced by a new one in case when it doesn't meet the achieved availability requirement, even though it is repairable failure; Otherwise it is replaced in time of the first irrepairable failure. Assumed that the j-th failure is repairable with probability ${\alpha}_j$ minimal repairs are allowed for repairable failure between replacements. Expected cost rate for preventive maintenance model is developed using NHPP(Non-Homogeneous Poisson Process) in order to determine the optimal number $n^*$, also numerical examples are shown in order to explain the proposed model. Since the proposed FNBM($\alpha$, $\delta$, $\gamma$)model includes Park FNBM model(1979) and Nakagawa FNBM(p)model(1983) this proposed model is thought to be better than previous model, especially for weapon system which requires availability as primary parameter.

물-에너지-식량-토지 넥서스를 통한 미래 쌀 수급 변화에 따른 자원별 이용량 변화 분석 (Assessment of the Impacts of Rice Self-sufficiency on National Rresources in Korea through Water-Energy-Food-Land Nexus Approach)

  • 이상현;최진용;유승환;허승오
    • 한국농공학회논문집
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    • 제60권4호
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    • pp.93-103
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    • 2018
  • The aim of this study is to apply the Water-Energy-Food-Land Nexus approach which can analyze the trade-offs among resources, and assess the holistic impacts of food security. First, we applied rice as a study crop and analyzed the trend of consumption of rice and the area of paddy fields. Second, the portfolios of water, energy, and land for rice production were constructed using data of footprints and productivity. Finally, the self-sufficiency ratio (SSR) of rice in target year was set as food security scenario and assessed the impacts of food security on water, energy, and land availability. In 2030, the SSR of rice decreased to 87 %, and water use for producing rice decreased from 4,728 to $3,350million\;m^3$, and the water availability index increased from 0.33 to 0.53. However, food security is essential issue and we set the 50 % and 100 % SSR of rice as high and low food security scenarios. For 100% SSR in 2030, about $3,508million\;m^3$ water was required and water availability index reached to 0.5. In other words, there is the trade-off between food security and water-energy-lands availability. Therefore, it is difficult to make a decision whether a high level of SSR is better or worse. However, this study showed the both positive and negative impacts by change of food security and it can be useful for setting the policy decision considering both food security and sustainable resource management at the same time.

혼합수리 과정을 고려한 소프트웨어성능 평가 모형 (A Software Performance Evaluation Model with Mixed Debugging Process)

  • 장규범;이종형
    • Communications for Statistical Applications and Methods
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    • 제18권6호
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    • pp.741-750
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    • 2011
  • 본 논문에서는 소프트웨어의 고장수리 과정 중 완전 수리와 불완전 수리를 모두 고려하는 혼합수리 모형을 제안하려고 한다. 이를 위해 소프트웨어가 가지고 있는 전체 결함의 유형을 고치기 쉬운 결함 유형과 고치기 어려운 결함 유형으로 나누고, 고치기 쉬운 결함의 경우에서는 수리 과정 중 결함을 완전하게 고친다고 가정한다. 또한 고치기 어려운 결함 유형은 완전 또는 불완전 수리가 가능하도록 가정하며, 이러한 가정과 마코프 과정(Markov process)하에서 소프트웨어 성능 평가를 위한 측도 중에 하나인 소프트웨어 가용성(software availability)을 제시하고자 한다.

시뮬레이션 모형과 실험설계법을 활용한 창정비 비용대 효과 분석 사례 (A Case Study on the Cost Effectiveness Analysis of Depot Maintenance Using Simulation Model and Experimental Design)

  • 김성곤;이상진
    • 한국시뮬레이션학회논문지
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    • 제26권3호
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    • pp.23-34
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    • 2017
  • 본 연구는 복수 품목을 정비하는 단일 정비부대의 정비 프로세스를 시뮬레이션으로 모델링하였다. 이를 통해 정비능력을 공유한 정비창이 최적 비용으로 구성품 가동률과 목표 가동율 등을 달성하는지를 분석할 수 있다. 구성품 가동률과 정비시간 등을 핵심 성과지표로 하여 육군 항공기 정비단 엔진 정비프로세스에 대한 시뮬레이션 모델을 구성하고 실증연구를 하였다. 영향요소의 식별을 위해 NOLH 실험설계법을 적용하여, 33가지 시나리오를 구성하고 다중회귀분석을 수행하였다. 이 비용분석 연구를 통해 정비 프로세스의 개선사항을 식별할 수 있었다. 본 연구는 시뮬레이션을 통해 복수품목을 정비하는 단일 정비부대의 비용대 효과 분석 모형을 제공했다는데 의의가 있다.

적분기를 포함한 시간지연 시스템에 대한 제어구조 설계 (Design of Controller for the System with Time-Delay)

  • 양승현;박종식;이석원
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2003년도 하계종합학술대회 논문집 V
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    • pp.2803-2806
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    • 2003
  • In this paper considers the design of the effective controllers for the plant with an integrator and a long dead time. The structure of the new DTC(Dead Time Compensator) that has an additive filter is proposed. Our DTC shows the improved performance in set-point response and disturbance rejection. Especially the bad effect of the long dead time in the disturbance rejection is fairly reduced by using the additive filter. illustrative examples are provided to show the availability of the proposed controller.

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확장된 기술수용모델을 적용한 실시간 화상강의 이용의도에 영향을 미치는 요인 연구 (Study on the Factors Affecting the Intention to Use Real-time Video Conferencing Using Extended Technology Acceptance Model)

  • 이장석;양승현;송병원
    • 한국콘텐츠학회논문지
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    • 제21권1호
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    • pp.292-310
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    • 2021
  • COVID 19의 영향이 교육계에도 직접적인 영향을 미치고 있다. 특히, 비대면 수업이 선택이 아닌 필수가 된 상황에서 실시간 화상강의에 대한 학습자의 만족과 이용의도를 높일 수 있는 방안에 대해 관심이 높아지고 있다. 본 연구에서는 화상강의 특성으로서 학습자-교수자 간 상호작용성, 사회적 실재감, 이용가능성, 자기효능감, 참여정도가 인지된 유용성과 이용 용이성, 학습 만족과 화상강의 이용의도에 영향을 미치는지 분석하였다. 연구결과, 인지된 이용 용이성에는 학습자-교수자 상호작용성과 이용가능성, 자기효능감이 정적인 영향을 미치는 것으로 나타났으며, 인지된 유용성에는 이용가능성을 제외한 모든 변인이 정적인 영향을 미치는 것으로 확인되었다. 또한, 인지된 유용성과 이용 용이성은 학습 만족과 화상강의 이용의도를 높이는 요인인 것으로 확인되었으며, 학습 만족 역시 화상강의 이용의도에 정적인 영향을 미치는 주요 변인인 것으로 나타났다. 본 연구는 실증적인 분석을 통해 향후 많은 교육 현장에서 활용하게 될 실시간 화상강의에 대해 여러 이론적, 실천적 시사점을 제공했다는 점에 의의가 있다.