• 제목/요약/키워드: Multiple-Case Study

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커먼레일 타입 피에조 인젝터의 정밀 다단분사 제어를 위한 분사특성 연구 (A Study on the Injection Characteristics of a Piezo Injector for Controlling Accurate Multiple Injection)

  • 박희범;김형익;박상기;이기형
    • 한국분무공학회지
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    • 제18권4호
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    • pp.176-181
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    • 2013
  • In this study, injection quantity, rate and spray image of multiple injections which are important design parameters for a piezo type injector have been investigated. Interval of injections and a number of injections in multiple injection strategy has been controlled to verify interaction of each injection. Spray characteristics of multiple injections have been researched through optical process with a high speed camera in a high pressure chamber. In addition, a method of RMS(Root Mean Square) process has been used for comprehending the distribution of injection easily. As a result, in case of piezo type injector, characteristics of injection quantity according to charging voltage and the difference of injection quantity between single and triple injection were confirmed. Also, injection rate for increasing injection duration was confirmed. And spray characteristics of multiple injections were improved; multiple injections were possible in a shorter time interval between each injection. With this study, a possibilities of more accurate multiple injection control would be expected.

복시를 호소하는 다계통위축증 환자 치험 1례 (A Case Study of Multiple System Atrophy Patient with Diplopia Using Korean Medical Treatment)

  • 정민호;손정화;조기호;문상관;권승원;정우상
    • 대한한방내과학회지
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    • 제38권2호
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    • pp.246-251
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    • 2017
  • In this study, a 54-year-old female woman diagnosed as Multiple System Atrophy (MSA) presented diplopia with other symptoms - gait disturbance, ataxia, sleep apnea, dysuria. She had been cared with Korean medical treatment - Herbal medicine, acupuncture, bee venom acupuncture, electroacupuncture, cupping, moxa. Notable improvement was observed in diplopia expressing time and Unified Multiple System Atrophy Rating Scale (UMSARS). For MSA patient with no typical treatment indispensable, Korean medical treatment may be effective.

미계측 관측 강수 자료 생성을 통한 제주도 지역의 수문총량 추정 (Estimating the Total Precipitation Amount with Simulated Precipitation for Ungauged Stations in Jeju Island)

  • 김남원;엄명진;정일문;허준행
    • 한국수자원학회논문집
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    • 제45권9호
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    • pp.875-885
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    • 2012
  • 본 연구에서는 미계측 강수자료를 생성하여 공간 해석함으로써 제주도의 정확한 수문총량을 산정하였다. 미계측 강수자료는 본 연구에서 제시된 수정된 다중회귀선형 모형으로 생성하였으며 공간강수량은 PRISM을 적용하여 구하였다. 수정된 다중선형회귀 모형에 의한 미계측 강수자료의 추정 값들은 기존의 강수 패턴과 유사한 양상을 나타내어 모형의 정확도가 우수한 것으로 나타났으며, 공간강수량의 해석결과는 Case 1(원자료)과 Case 2(미계측 강수자료를 보완한 자료)의 연평균 강수량이 약 1.5%의 미미한 차이를나타내었으나 고도별 연평균 강수량 차이는 최대 37.4%가 증가하는 것으로 산정되었다. 따라서 본 연구에서 제안한 미계측 관측 자료 생성방법은 현재 관측소의 밀도가 낮은 곳과 국지적으로 강수량의 변화가 큰 곳에서의 수문총량의 산정시 유용할 것으로 판단된다.

A Study on Collision Avoidance Action in the Situation of Encountering Multiple Ships by the Reserve Officer

  • Park, Deuk-Jin;Yim, Jeong-Bin;Yang, Hyeong-Sun
    • 해양환경안전학회지
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    • 제24권3호
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    • pp.346-351
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    • 2018
  • The proportion of collision in the total marine accidents is high. The main causes of collisions are navigation rule violation, safety speed violation, neglected watch-keeping and improper collision avoidance action. There are two main ways of avoiding collision situations during maritime navigation: the method of altering course and reducing ship's speed. The purpose of this study is to analyze the result of the collision avoidance action of the reserve officer in case of encountering a multiple number of ships using the ship handling simulator. Full-mission ship handling simulator was used to experiment the situation scenarios that encountered multiple ships. After the experiment, the questionnaire about the experiment was investigated. A total of 50 subjects were participated in the experiment. Experimental results showed that the number of the experimenters who used the engine was 11 and the number of the experimenters who did not use the engine was 39. In the case of using the engine, there were 0 collision accident, 1 grounding accident, and 10 no accidents. However, when the engine was not used, there were 28 collision accidents, 2 grounding accidents, and 9 no accidents. The causes of these results can be found in the survey results. 74 % of the non used engine participants said they were hesitate to use the engine. As can be seen from these results, the reserve officer are hesitant to use the engine and need a way to get correct of it. Maritime course subject can emphasize the importance of using ship's engines and case study also can be it. So, It is considered that various case study scenario will need to developed by various tools in the future.

3지 신호교차로의 교통사고 발생모형 - 청주시를 사례로 - (Traffic Accident Models of 3-Legged Signalized Intersections in the Case of Cheongju)

  • 박병호;한상욱;김태영
    • 한국안전학회지
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    • 제24권2호
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    • pp.94-99
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    • 2009
  • This study deals with the traffic accidents at the 3-legged signalized intersections in Cheongu. The goals are to analyze the geometric, traffic and operational conditions of intersections and to develop a various functional forms that predict the accidents. The models are developed through the correlation analysis, the multiple linear, the multiple nonlinear, Poisson and negative binomial regression analysis. In this study, two multiple linear, two multiple nonlinear and two negative binomial regression models were calibrated. These models were all analyzed to be statistically significant. All the models include 2 common variables(traffic volume and lane width) and model-specific variables. These variables are, therefore, evaluated to be critical to the accident reduction of Cheongju.

Multiple dynamic programming에 관한 연구 (A Study of Multiple Dynamic Programming)

  • 박영문
    • 전기의세계
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    • 제21권1호
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    • pp.13-16
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    • 1972
  • Dynamic Programming is regarded as a very powerful tool for solving nonlinear optimization problem subject to a number of constraints of state and control variables, but has definite disadvantages that it requires much more computing time and consumes much more memory spaces than other technigues. In order to eliminate the above-mentioned demerits, this paper suggests a news technique called Multiple Dynamic Programming. The underlying principles are based on the concept of multiple passes that, instead of forming fin lattices in time-state plane as adopted in the conventional Dynamic Programming, the Multiple Dynamic Programming constitutes, at the first pass, coarse lattices in the feasible domain of time-state plane and determines the optimal state trajectory by the usual method of Dynamic Programming, and at the second pass again constitutes finer lattices in the narrower domain surrounded by both the upperand lower edges next to the lattice edges through which the first pass optimal trajectory passes and determines the more accurate optimal trajectory of state, and then at the third pass repeats the same processes, and so on. The suggested technique insures remarkable curtailment in amounts of computer memory spaces and conputing time, and its applicability has been demonstrated by a case study on the hydro-thermal power coordination in Korean power system.

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한약치료와 표적항암요법(아피니토)을 병행하여 부분 관해 된 신세포암 간전이 환자 1례 (A Case Report of Partial Remission of Renal Cell Carcinoma with Multiple Liver Metastases Treated with Korean Herbal Medicine in Conjunction with Targeted Anticancer Therapy Afinitor)

  • 장성환;박지혜;유화승
    • 대한암한의학회지
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    • 제22권2호
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    • pp.13-24
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    • 2017
  • Objectives: The purpose of this study is to report the effect of Korean Herbal Medicine (KHM) on a Renal Cell Carcinoma with multiple liver metastases patient. Methods: One renal cell carcinoma with multiple liver metastases patient was treated by KHM in conjunction with targeted anticancer agent (Afinitor). The effect of KHM was measured by scanning with Computed Tomography (CT), Blood Test, Visual Analogue Scale (VAS) and Eastern Cooperative Oncology Group scale. Results: Multiple hepatic tumors were reduced after the treatment during 5 months (Partial Remission, PR). As treatment was performed, complications induced by targeted anticancer agent (Afinitor) were alleviated. Conclusions: This case provides us a possibility that Korean Herbal Medicine offers potential benefits for renal cell carcinoma with multiple liver metastases patient.

다중퍼지목표계획법을 이용한 PULP 제조공정의 최적화에 관한 연구 (Optimal Design of PULP Process Using Multiple Fuzzy Goal Programming)

  • 박주영;신태용;이동현
    • 산업경영시스템학회지
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    • 제15권26호
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    • pp.59-66
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    • 1992
  • This Paper, first, tries to optimize the output specifications with uncertain characteristics. And then aims to solve the problem not only by making use of transformed multiple regression equation which can yield objective function of output characteristics but also by formulating developed multiple fuzzy goal programming using fuzzy set theory which can treat uncertainty easily, and the efficiency of these techniques, will be also demonstrated through a case study.

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부유식 다수 풍력 발전기에 작용하는 비대칭 공력 하중의 영향 (Influence of Asymmetric Aerodynamic Loading on Multiple Unit Floating Offshore Wind Turbine)

  • 배윤혁
    • 한국해양공학회지
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    • 제29권3호
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    • pp.255-262
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    • 2015
  • The present study developed a numerical simulation tool for the coupled dynamic analysis of multiple turbines on a single floater (or Multiple Unit Floating Offshore Wind Turbine (MUFOWT)) in the time domain, considering the multiple-turbine aero-blade-tower dynamics and control, mooring dynamics, and platform motions. The numerical tool developed in this study was designed based on and extended from the single-turbine analysis tool FAST to make it suitable for multiple turbines. For the hydrodynamic loadings of floating platform and mooring-line dynamics, the CHARM3D program developed by the authors was incorporated. Thus, the coupled dynamic behavior of a floating base with multiple turbines and mooring lines can be simulated in the time domain. To investigate the effect of asymmetric aerodynamic loading on the global performance and mooring line tensions of the MUFOWT, one turbine failure case with a fully feathered blade pitch angle was simulated and checked. The aerodynamic interference between adjacent turbines, including the wake effect, was not considered in this study to more clearly demonstrate the influence of the asymmetric aerodynamic loading on the MUFOWT. The analysis shows that the unbalanced aerodynamic loading from one turbine in MUFOWT may induce appreciable changes in the performance of the floating platform and mooring system.

On successive machine learning process for predicting strength and displacement of rectangular reinforced concrete columns subjected to cyclic loading

  • Bu-seog Ju;Shinyoung Kwag;Sangwoo Lee
    • Computers and Concrete
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    • 제32권5호
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    • pp.513-525
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    • 2023
  • Recently, research on predicting the behavior of reinforced concrete (RC) columns using machine learning methods has been actively conducted. However, most studies have focused on predicting the ultimate strength of RC columns using a regression algorithm. Therefore, this study develops a successive machine learning process for predicting multiple nonlinear behaviors of rectangular RC columns. This process consists of three stages: single machine learning, bagging ensemble, and stacking ensemble. In the case of strength prediction, sufficient prediction accuracy is confirmed even in the first stage. In the case of displacement, although sufficient accuracy is not achieved in the first and second stages, the stacking ensemble model in the third stage performs better than the machine learning models in the first and second stages. In addition, the performance of the final prediction models is verified by comparing the backbone curves and hysteresis loops obtained from predicted outputs with actual experimental data.