• 산업경영시스템학회지
• /
• 제39권4호
• /
• pp.49-59
• /
• 2016

Naval combat system developed in-country is progressing at an alarming rate since 2000. ROK navy will be achieved all vessels that have combat system in the near future. The importance of System Engineering and Integrated Logistics Support based on reliability analysis is increasing. However, reliability analysis that everyone trusted and recognized is not enough and applied practically for development of Defense Acquisition Program. In particular, Existing Reliability Analysis is focusing on reliability index (Mean Time Between Failure (MTBF) etc.) for policy decision of defense improvement project. Most of the weapon system acquisition process applying in the exponential distribution simply persist unreality due to memoryless property. Critical failures are more important than simple faults to ship's operator. There are no confirmed cases of reliability analysis involved with critical failure that naval ship scheduler and operator concerned sensitively. Therefore, this study is focusing on Mean Time To Critical Failure (MTTCF), reliability on specific time and Operational Readiness Float (ORF) requirements related to critical failure of Patrol Killer Guided missile (PKG) combat system that is beginning of naval combat system developed in-country. Methods of analysis is applied parametric and non-parametric statistical techniques. It is compared to the estimates and proposed applications. The result of study shows that parametric and non-parametric estimators should be applied differently depending on purpose of utilization based on test of normality. For the first time, this study is offering Reliability of ROK Naval combat system to stakeholders involved with defense improvement project. Decision makers of defense improvement project have to active support and effort in this area for improvement of System Engineering.

• 성인간호학회지
• /
• 제12권4호
• /
• pp.517-532
• /
• 2000

The purpose of this study was to develop a critical pathway for case management of patients who have received Lumbar Laminectomy because of low back pain, arm and leg numbness, and radiating pain in the leg. For this study, a preliminary critical pathway was developed through a review of the literature including five critical pathways which are currently being used in the USA. In order to identify the overall service contents required by these patients, 30 cases were analyzed. These cases were taken from medical records of those with Lumbar Laminectomy between January, 1998 and December, 1998 in the department of neurosurgery at the Pusan National University Hospital in Pusan. An expert validity test was done for the preliminary critical pathway, a clinical validity test was also done using 12 patients with Lumbar Laminectomy between October 1, 1999 and January 31, 2000. After these processes, the final critical pathway was developed. The results are summarized as follows. 1. The vertical axis of the critical pathway includes the following eight items: assessment, consultation, diet, test, medication, treatment, activity, education/ discharge planning. The horizontal axis includes the time from the start of hospitalization to discharge. Analysis of the 30 medical records was done. analysis of the service contents showed the horizontal axis of the preliminary critical pathway was set from hospitalization to the 12th post operation day and the vertical axis was set to include eight items, the contents which should have occurred, according to the time frames of the horizontal axis. 2. As a result of the expert validity test, it was found that among the 233 items, 203 showed over 88% agreement and 30 of them showed less than 88% agreement, which were then revised or deleted from the critical pathway. At the preliminary meeting for the clinical validity test, the time of hospitalization on the horizontal axis was shortened to the 10th post operation day. A clinical validity test was done with 12 patients with Lumbar Laminectomy. All the cases progressed according to the critical pathway although some variances were noted in assessment, consultation, test, medication, and treatment. 3. Based on these results, a final critical pathway was determined. In conclusion, this critical pathway is partially applicable to the care of patients with Lumbar Laminectomy and needs further investigation.

• 한국건설관리학회논문집
• /
• 제6권6호
• /
• pp.81-89
• /
• 2005

건설사업은 위험에 대한 노출수위가 크기 때문에 프로젝트의 공정을 관리하는 적극적인 위험관리가 강하게 요구되고 있으나 현재의 일반적인 공정관리기법은 위험인지 및 위험분석을 하기에는 부적합한 것이 사실이다. 따라서 본 연구는 현재의 공정관리 문제점을 개선하기 위한 공정관리 모델의 개발을 목적으로, 건설현장에서 실질적 인 위험관리를 수행할 수 있는 모델을 개발하였다. 위험관리에 초점을 둔 새로운 공정관리모델은 주공정 관리 및 위험주공정 관리를 함께 수행할 수 있을 것이다.

• 전자공학회논문지C
• /
• 제36C권4호
• /
• pp.1-16
• /
• 1999

본 논문에서는 테스트 생성 과정에서 자주 사용되는 임계의 확장 개념으로 임계-쌍을 정의한다. 그리고 임계의 특성을 나타내는 요소로서 임계성, 임계율, 임계설정율 등을 정의한다. 이 요소들을 이용하여 임계-쌍의 사용이 단일 임계의 사용보다 더 효율적이라는 것을 입증하고, FFR에서의 테스트 패턴 생성 시에 임계값에 대한 평가 회수, 경로선의 탐색 회수 및 생성 시간에서 더 효율적이라는 것을 보여준다. 시뮬레이션을 통해서 ISCAS85 벤치마크 테스트 회로에 대한 실험 결과를 비교 분석한다.

• Journal of Computing Science and Engineering
• /
• 제8권1호
• /
• pp.34-42
• /
• 2014

Time-predictability of computing is critical for hard real-time and safety-critical systems. However, currently there is no metric available to quantitatively evaluate time-predictability, a feature crucial to the design of time-predictable processors. This paper first proposes the concept of architectural time-predictability, which separates the time variation due to hardware architectural/microarchitectural design from that due to software. We then propose the standard deviation of clock cycles per instruction (CPI), a new metric, to measure architectural time-predictability. Our experiments confirm that the standard deviation of CPI is an effective metric to evaluate and compare architectural time-predictability for different processors.

• 한국정보과학회:학술대회논문집
• /
• 한국정보과학회 2003년도 봄 학술발표논문집 Vol.30 No.1 (A)
• /
• pp.226-228
• /
• 2003

실시간 운영체제(Real-Time Operating System)는 그 실행환경상 시스템이 예상치 못한 특정 이벤트가 발생하는 악 조건속에서도 태스크 수행의 데드라인을 초과하지 않도록 시간적인 측면의 determinism을 보장하는 안정된 스케줄링 기능을 갖춘 운영체제이다. 또한, 예상치 못한 fault 를 미연에 방지할 수 있는 장치를 가지고 있어야 한다. 본 논문에서는 예상치 못한 fault 를 미연에 방지하기 위하여 필요한 운영체제를 설계 및 구현하는데 그 목적이 있다.

• JSTS:Journal of Semiconductor Technology and Science
• /
• 제16권6호
• /
• pp.771-780
• /
• 2016

Detecting a set of longest paths is one of the crucial steps in static timing analysis and optimization. Recently, the process variation during manufacturing affects performance of the circuit design due to nanometer feature size. Measuring the performance of a circuit prior to its fabrication requires a considerable amount of computation time because it requires multi-corner and multi-mode analysis with process variations. An efficient algorithm of detecting the K-most critical paths in multi-corner multi-mode static timing analysis (MCMM STA) is proposed in this paper. The ISCAS'85 benchmark suite using a 32 nm technology is applied to verify the proposed method. The proposed K-most critical paths detection method reduces about 25% of computation time on average.

• 한국식품조리과학회지
• /
• 제2권2호
• /
• pp.76-83
• /
• 1986

Time and temperature, pH and Aw, and microbiological evaluation were made to identify critical control points during various phases in product flow of chicken soup preparation in a university foodservice establishment. The results are summarised as follows: 1) Time and temperature data indicated that the phases of cooling after cooking, post-preparation, and holding ingredients at room temperature before assembly were critical. 2) pH and Aw values were in favorable for microbial growth. 3) Microbiological data indicated that the phases of basic ingredients. post-preparation and holding ingredients before assembly were critical. 4) Critical control points identified were; basic ingredients, cooling after cooking, post-preparation, holding before assembly and service, and assembly and service. 5) Several guidelines were suggested for the effective qualitly control program.

• 간호행정학회지
• /
• 제8권3호
• /
• pp.475-488
• /
• 2002

Purpose : The purpose of this study is to establish a basis of patient classification in the ICU by selecting the determination critical indicator of special nursing activities that show high interrilation with daily total nursing care time. Method : This study is composed of the six steps. The first step is the listing direct nursing activities in the ICU. The last step is the determination indicator of each group were selected on the basis of their relationship to the daily total nursing care time of each patient classification group and each nursing activity. Result : Result shows that: 1. direct nursing activities in the ICU are 149 items of 13 territories. 2. the average time and frequency for each direct nursing activities 3. total direct nursing care time of 42 patients in ICU for 2 days. According to the results of the Cluster analysis, the first group is 10 people, the second group is 13 people, the third group is 16 people, the fourth group is 3 people. 4. Determination critical indicator is the item that is r>0.6(p<0.05) of Pearson Correlation between each patient daily total nursing care time and 149 items of nursing activities. The nursing activities selected were as follows: 2 items in the first group, 17 items in the second group. 16 items in the third group, 8 items in the fourth group. Conclusion : This study can help future studies which measure nursing activities standard time or assigns value to nursing activities time.

• Computers and Concrete
• /
• 제20권2호
• /
• pp.119-127
• /
• 2017

Time-dependent buckling of embedded straight concrete columns armed with Silicon dioxide($SiO_2$) nano-particles exposed to fire is investigated in the present study for the fire time. The column is simulated mathematically with Timoshenko beam model. The governing mass conservation equations to describe heat and moisture transport in concrete containing free water, water vapor, and dry air in conjunction with the conversion of energy are considered. The characteristics of the equivalent composite are determined using Mori-Tanaka approach. The foundation around the column is simulated with spring and shear layer. Employing nonlinear strains-displacements, energy methods and Hamilton's principal, the governing equations are derived. Differential quadrature method (DQM) is used in order to obtain the critical buckling load and critical buckling time of structure. The influences of volume percent of $SiO_2nano-particles$, geometrical parameters, elastic foundation and concrete porosity are investigated on the time-dependent buckling behaviours of structure. Numerical results indicate that reinforcing the concrete column with $SiO_2nano-particles$, the structure becomes stiffer and the critical buckling load and time increase.