• 제목/요약/키워드: Critical Number

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통합적 고찰과 키워드 분석을 이용한 최근 10년(2008-2017) 동안의 국내 중환자간호 연구 동향 분석 (A Study of the Trends in Korean Nursing Research on Critical Care in the Last 10 Years (2008-2017) Using Integrated Review and Key Word Analysis)

  • 강지연;김수경;조영신;고현영;백지현;이수진
    • 중환자간호학회지
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    • 제11권2호
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    • pp.75-85
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    • 2018
  • Purpose : The purpose of this study was to examine the possible direction of critical care nursing research in the future by analyzing the trends of recent Korean studies. Method : Using a database search, we selected 263 articles on critical care nursing that were published in Korean journals between 2008 and 2017. Then, we conducted an integrative review of the contents of the selected articles and analyzed the English abstracts using the relevant packages and functions of the R program. Results : The number of studies concerning critical care nursing has increased over the 10-year period, and the specific topic of each study has diversified according to the time at which it was conducted. In terms of quality, the majority of the research was published in high-level academic journals. The key words regularly studied over the past decade were: knowledge, delirium, education, restraint, stress, and infection. Studies related to vancomycin-resistant enterococci infection, compliance, and standards have decreased, while studies related to death, communication, and safety have increased. Conclusion : Randomized controlled trials and protocol research for evidence-based critical care need to be conducted, as does research on family involvement. The key word analysis of unstructured text used in this study is a relatively new method; it is suggested that this method be applied to various critical care nursing research and develop it methodologically.

Critical Velocity of Fluidelastic Vibration in a Nuclear Fuel Bundle

  • Kim, Sang-Nyung;Jung, Sung-Yup
    • Journal of Mechanical Science and Technology
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    • 제14권8호
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    • pp.816-822
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    • 2000
  • In the core of the nuclear power plant of PWR, several cases of fuel failure by unknown causes have been experienced for various fuel types. From the common features of the failure pattern, failure lead time, flow conditions, and flow induced vibration characteristics in nuclear fuel bundles, it is deduced that the fretting wear failure of the fuel rod at the spacer grid position is due to the fluidelastic vibration. In the past, fluidelastic vibration was simulated by quasi -static semi-analytical model, so called the static model, which could not account for the interaction between the rods within a bundle. To overcome this defect and to provide for more flexibilities applicable to the fuel bundle, Tanaka's unsteady model was modified to accomodate the geometrical differences and governing parameter changes during the operations such as the number of rods, pitch to diameter ratio (P/D), spring force, damping coefficient, etc. The critical velocity was calculated by solving the governing equations with the MATLAB code. A comparison between the estimated critical velocity and the test result shows a good agreement. Finally, the level of decrease of the critical velocity due to the reduction in the spring force and reduced damping coefficient due to the radiation exposure is also estimated.

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소규모 유역에서 자연방류형 단일저류지의 임계지속기간 분석 (The Analysis of Critical Duration of uncontrolled single detention facility in Small Catchment)

  • 박종영;신창동;이정식
    • 한국방재학회 논문집
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    • 제5권2호
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    • pp.17-28
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    • 2005
  • 본 연구의 목적은 소규모 유역에서 홍수 저류시설물과 홍수 조절시설물 사이의 임계지속기간을 평가하는데 있다. 4개 소규모 유역을 통하여 수문분석을 실시하였으며, 유효우량은 NRCS 유효우량 산정방법으로 산정하였다. 홍수 저류시설물과 홍수 조절시설물의 임계지속기간은 허용방류량 고정개념을 이용하여 평가하였다. 허용방류량 고정개념을 이용한 경우 최대 저류비를 발생시키는 시간분포는 Huff 2분위 시간분포로 나타났으며, 자연방류형 단일저류지에서 홍수 조절시설물의 임계지속기간은 홍수 저류시설물의 임계지속기간과 유사한 것으로 나타났다.

Curvilinear free-edge form effect on stability of perforated laminated composite plates

  • Zerin, Zihni;Basoglu, Muhammed Fatih;Turan, Ferruh
    • Structural Engineering and Mechanics
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    • 제61권2호
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    • pp.255-266
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    • 2017
  • In this study, self-supporting roofing elements especially convenient for large-span structures such as stadium, airport terminal, mall, coliseum, etc. were examined with respect to critical buckling load. These elements were assumed as laminated composite plates and, variation of free-edge forms, cutout types and lamination configurations were used as design parameters. Based on the architectural feature and structural requirements, the effects of curvilinear free-edge form on critical buckling load were focused on in this research. Within this scope, 14 types of lamination configuration were specified according to various orientation angle, number and thickness of plies with a constant value of total plate thickness. Besides that, 6 different types of cutout and 3 different free-edge forms were determined. By combining all these parameters 294 different critical buckling load analyses were performed by using ANSYS Mechanical software based on finite element method. Effects of those parameters on critical buckling load were evaluated referring to the obtained results. According to the results presented here, it may be concluded that lamination conditions have more significant influence on the critical buckling load values than the other parameters. On the other hand, it is perceived that curvilinear free-edge forms explicitly undergo changings depending on lamination conditions. For future work, existence of delamination might be considered and progression of the defect could be investigated by using non-linear analysis.

가정배달 노인급식서비스 작업공정관리 모형개발을 위한 PERT-Type System의 적용 (Application of a PERT-Type System on Work Management in Home-Delivered Meals Service Program for Elderly)

  • 양일선;채인숙;유일근
    • Journal of Nutrition and Health
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    • 제34권6호
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    • pp.701-714
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    • 2001
  • The purpose of this study was to apply a PERT-type system, a combination of the project evaluation and review technique(PERT) and critical path method(CPM) on the employees' work time management of flood preparation, assembly, transportation and cleaning in home-delivered meals program for elderly The resources allotment heuristic program was developed by considering the number of employees and cooking utilities, being limited resources of home- delivered meals program. This program could assign the employees to perform the works included in flood preparation, assembly, transportation ind cleaning. Critical path and activities ware identified by PERT-type system on the basic of work time investigation in five senior centers. Work sheets were invented to perform the work by the shortest path with flexible employees'maximum flow As a result of the work time investigation, the most prevalent activities were ones of preparation in center C and E. Besides, the preparation(over fifty percent) was the most proportion among flood preparation, assembly, transportation and cleaning in center C and E. Critical path and activities of 'C'center were cucumber in sauce preparation path and assembly, wrapping in assembly path and case delivery in transportation path. Critical path and activities of 'E'center were Pan-fried Potato Preparation Path and assembly, case covering, wrapping in assembly Path. The work sheet invented by the heuristic program and PERT-type system reduced the work completion time and man hours in both centers.

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SW 테스트 자동화 구현을 위한 핵심성공요인에 관한 연구 (Critical Success Factors for Implementing Software Test Automation)

  • 김성용;민대환;임성택;채봉수
    • Journal of Information Technology Applications and Management
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    • 제27권6호
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    • pp.101-116
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    • 2020
  • This study attempts to derive critical success factors and prioritize activities for implementing the automation of software test. Software testing proceeds in five steps of test plan, test case design, test scripting & test environment setup, test execution & evaluation, and test closure. From the literature, twenty influence factors in the five steps were identified. Focus Group Interviews with ten experts in software testing selected fourteen factors on the basis of importance and feasibility. Some factors were further divided to clarify their meanings and the number of influence factors finally became twenty one. A survey on the influence factors was conducted with 75 IT professionals. An importance-feasibility analysis was applied to the survey responses and classified the influence factors into four groups of essential factors, critical factors, low priority factors, and minimal factors. Essential factors include objectives for test automation, strategies for test automation, test automation training, test automation education, setting up test automation environment, setting up test environment, test automation tool selection. Critical factors include management's continued support, management's continued interest, role of automation engineers, and skills of automation engineers. This result suggests that a lot of efforts should be put into SW test plan for the successful SW test automation and SW automation should proceed in consideration with the priorities and resource consumption.

Assessing Critical Quality Metrics for Successful Baseline Construction Scheduling

  • Bivans, John;Choi, Jin Ouk
    • 국제학술발표논문집
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    • The 9th International Conference on Construction Engineering and Project Management
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    • pp.1241-1241
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    • 2022
  • In the current construction industry, difficulty arises in creating an adequate baseline schedule to establish a fundamental plan for construction. This presentation will present the research findings which investigated industry-recognized schedule metrics that aid in the successful implementation of said schedule. Industry organizations (Association for the Advancement of Cost Engineering, the Government Accountability Office, the Project Management Institute, and local city, state, and county government offices) provide standardized guidelines with specific metrics requirements to ensure successful implementation. However, most of those metrics are substantiated or validated in their effectiveness. The study examined the impact between these industry-recognized critical metrics and three distinct scheduling characteristics: Project Type, Project Duration, and Project Density (number of activities within a schedule). The research results showed that, among the 12 various schedules evaluated in parallel with 20 industry-recognized critical metrics, seven metrics substantially demonstrate a significant impact on a project schedule's success. Furthermore, six of the seven metrics directly correlate to at least one of the three scheduling characteristics outlined. As a result, this research has established more predictable outcomes based on impacts between three distinct project characteristics and 20 of the most discussed/researched critical scheduling metrics in the field. This allows management teams to have more confidence in establishing critical milestones and accurate turnover dates from the start of the project through its final completion.

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Influence of Reynolds Number and Scale on Performance Evaluation of Lift-type Vertical Axis Wind Turbine by Scale-model Wind Tunnel Tests

  • Tanino, Tadakazu;Nakao, Shinichiro;Miyaguni, Takeshi;Takahashi, Kazunobu
    • International Journal of Fluid Machinery and Systems
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    • 제4권2호
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    • pp.229-234
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    • 2011
  • For Lift-type Vertical Axis Wind Turbine (VAWT), it is difficult to evaluate the performance through the scale-model wind tunnel tests, because of the scale effect relating to Reynolds number. However, it is beneficial to figure out the critical value of Reynolds number or minimum size of the Lift-type VAWT, when designing this type of micro wind turbine. Therefore, in this study, the performance of several scale-models of Lift-type VAWT (Reynolds number : $1.5{\times}10^4$ to $4.6{\times}10^4$) was investigated. As a result, the Reynolds number effect depends on the blade chord rather than the inlet velocity. In addition, there was a transition point of the Reynolds number to change the dominant driving force from Drag to Lift.

수평 와이어와 충돌하는 액적 거동에 관한 연구 (A Study of the Behavior of Droplet Impacting on a Horizontal Wire)

  • 강원준;김준영;박지훈;강보선
    • 한국분무공학회지
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    • 제25권3호
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    • pp.103-110
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    • 2020
  • In this study, the behavior of water droplet impacting on a thin horizontal wire was visualized by time-delay photography. The impact behavior modes, critical capture speed and trapped mass were analyzed by changing the droplet size, velocity, wire diameter and eccentricity ratio. As the Weber number increased, the hanging, merging, and splitting modes appeared sequentially for the case of central impact, and the hanging and non-splitting modes appeared for the case of off-center impact. The boundary We number of each mode was affected by the diameter ratio. The critical capture speed was affected much by the degree of eccentricity. For all diameter ratios, it was higher for the case of central impact than for off-center impact. The trapped mass was larger for the case of central impact than for off-center impact and it increased with the smaller We number and the larger diameter ratio.