• 제목/요약/키워드: System-level Analysis

검색결과 7,349건 처리시간 0.037초

Analysis of Multi-Level Inventory Distribution System for an Item with Low Level of Demand

  • Lee, Jin-Seok;Yoon, Seung-Chul
    • 산업경영시스템학회지
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    • 제23권60호
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    • pp.11-22
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    • 2000
  • The main objective of this research is to analyze an order point and an order quantity of a distribution center and each branch to attain a target service level in multi-level inventory distribution system. In case of product item, we use the item with low volume of average monthly demand. Under the continuous review method, the distribution center places a particular order quantity to an outside supplier whenever the level of inventory reaches an order point, and receives the order quantity after elapsing a certain lead time. Also, each branch places an order quantity to the distribution center whenever the level of inventory reaches an order point, and receives the quantity after elapsing a particular lead time. When an out of stock condition occurs, we assume that the item is backordered. For considering more realistic situations, we use generic type of probability distribution of lead times. In the variable lead time model, the actually achieved service level is estimated as the expected service level. Therefore, this study focuses on the analysis of deciding the optimal order point and order quantity to achieve a target service level at each depot as a expected service level, while the system-wide inventory level is minimized. In addition, we analyze the order level as a maximum level of inventory to suggest more efficient way to develop the low demand item model.

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국내 전력계통 안정화를 위한 다단계 부하차단 제어전략 수립에 관한 연구 (A Study on Multi Level Load Shedding Control Scheme Strategy for Stabilization of the Korean Power System)

  • 이윤환
    • 전기학회논문지P
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    • 제65권4호
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    • pp.255-261
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    • 2016
  • Korean Power System are operating a load shedding system to prevent voltage instability phenomenon caused by severe line contingencies. In order to apply the load shedding scheme should be selected a location, amount, delay time. Current load shedding system is load shedding amount that has been calculated in the steady-state analysis to load shed the total amount in first level, load shedding amount calculated in advance, it is possible to perform an unnecessary load shedding. In this paper, set a multi-level load shedding control strategy step-by-step selection of load shedding amount for the prevention of excessive load shedding. In addition, through a voltage resilience analysis of the power system by applying motor load ratio and sensitivity parameter to selection the multi level load shedding ratio and delay time. For this reason, to take advantage of the limit data of interchange power, by utilizing interface power flow data to set a multi-level load shedding control strategy for the stabilization of the Korean Power System.

공공정보화사업 제안요청서 품질분석 : 시스템 운영 개념을 중심으로 (Quality Analysis of the Request for Proposals of Public Information Systems Project : System Operational Concept)

  • 박상휘;김병초
    • 한국IT서비스학회지
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    • 제18권2호
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    • pp.37-54
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    • 2019
  • The purpose of this study is to present an evaluation model to measure the clarification level of stakeholder requirements of public sector software projects in the Republic of Korea. We tried to grasp the quality of proposal request through evaluation model. It also examines the impact of the level of stakeholder requirements on the level of system requirements. To do this, we analyzed existing research models and related standards related to business requirements and stakeholder requirements, and constructed evaluation models for the system operation concept documents in the ISO/IEC/IEEE 29148. The system operation concept document is a document prepared by organizing the requirements of stakeholders in the organization and sharing the intention of the organization. The evaluation model proposed in this study focuses on evaluating whether the contents related to the system operation concept are faithfully written in the request for proposal. The evaluation items consisted of three items: 'organization status', 'desired changes', and 'operational constraints'. The sample extracted 217 RFPs in the national procurement system. As a result of the analysis, the evaluation model proved to be valid and the internal consistency was maintained. The level of system operation concept was very low, and it was also found to affect the quality of system requirements. It is more important to clearly write stakeholders' requirements than the functional requirements. we propose a news classification methods for sentiment analysis that is effective for bankruptcy prediction model.

수준관리체계를 통한 핵심 직무역량 향상 방안 - 보안검색요원 판독등급제 중심으로 - (A Plan to Improve Core Job Skills through the Level Management System : Focusing on the X-ray Screening Rating System)

  • 김동민;백정선
    • 품질경영학회지
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    • 제51권4호
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    • pp.677-689
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    • 2023
  • Purpose: The purpose of this study is to design a x-ray screening rating system to improve X-ray screening ability, which is a core job competency of security screener at Incheon International Airport, and to verify its effectiveness through empirical analysis to suggest ways to improve the level management system. Methods: In this study, the effectiveness of the research model was analyzed using T-test tests for effect analysis based on the empirical analysis results derived through the competency evaluation model, the screening rating system. Results: The results of this study are as follows. The average score for regular education before the implementation of the x-ray screening rating system was 94.1 points, but after the implementation of the x-ray screening rating system, the average score for regular education was 95.5 points, an average of 1.4 points increased. In addition, the proportion of those with 95 or more points classified as high scorers also increased significantly from 51.1% to 69.3%. Conclusion: The X-ray screening rating system of security inspectors will systematically manage the level of screening ability, which is a key job competency, and play a strong role in improving competency, while preventing security accidents through early identification and intensive training of level-lowers.

한계분석법과 유전알고리즘을 결합한 다단계 다계층 재고모형의 적정재고수준 결정 (Optimal Spare Part Level in Multi Indenture and Multi Echelon Inventory Applying Marginal Analysis and Genetic Algorithm)

  • 정성태;이상진
    • 경영과학
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    • 제31권3호
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    • pp.61-76
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    • 2014
  • There are three methods for calculating the optimal level for spare part inventories in a MIME (Multi Indenture and Multi Echelon) system : marginal analysis, Lagrangian relaxation method, and genetic algorithm. However, their solutions are sub-optimal solutions because the MIME system is neither convex nor separable by items. To be more specific, SRUs (Shop Replaceable Units) are required to fix a defected LRU (Line Replaceable Unit) because one LRU consists of several SRUs. Therefore, the level of both SRU and LRU cannot be calculated independently. Based on the limitations of three existing methods, we proposes a improved algorithm applying marginal analysis on determining LRU stock level and genetic algorithm on determining SRU stock level. It can draw optimal combinations on LRUs through separating SRUs. More, genetic algorithm enables to extend the solution search space of a SRU which is restricted in marginal analysis applying greedy algorithm. In the numerical analysis, we compare the performance of three existing methods and the proposed algorithm. The research model guarantees better results than the existing analytical methods. More, the performance variation of the proposed method is relatively low, which means one execution is enough to get the better result.

보건진료소 정보시스템을 이용한 보건진료원의 업무 분석 (Service Analysis of Community Health Nurse Practitioner using Information System)

  • 이정렬;유태엄
    • 한국보건간호학회지
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    • 제17권1호
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    • pp.26-34
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    • 2003
  • The purpose of this study was to analyze the activities of Community Health Nurse Practitionses using the Community Health Post Information System(CHPIS). The information system that have been introduced in 1994 and used by 400 Community Health Posts(CHPs) since 1997, which is about $20\%$ of the total CHPs nationwide. Twenty-five CHPs from two provinces participated in the analysis. Seventy-two percent of the CHPs among the participating CHPs started using the system since 1996. The degree of utilization of the information system was classified into three groups (i. e., high. medium, and low). The results revealed that only $48\%$ utilized the system with high level. The areas of analysis of the information system included characteristics of community residents, environmental attributes, and job analysis of Community Health Nurse Practitioners(CHNPs). The study results indicated that primary health care and drug demand and supply system showed the highest level of satisfaction in utilizing the information system by CHNPs.

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진공청소기용 팬-모터 어셈블리의 시스템-레벨 분석 (System-level Analysis of a Fan-motor Assembly for Vacuum Cleaner)

  • 박창환;박경현;장경식
    • 한국유체기계학회 논문집
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    • 제20권1호
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    • pp.5-14
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    • 2017
  • A fan-motor assembly in a vacuum cleaner is analyzed through system-level analysis method. This system consisted of three components, a fan, motor, and the flow resistance of the motor, or of the vacuum cleaner. System-level analysis method is characterized by the combination of torque matching at a constant throttling condition between the fan and the motor and the pressure drop at a constant flow rate due to the flow resistance of the motor, or of the vacuum cleaner. The performance characteristics of the fan-motor assembly and the vacuum cleaner system could be predicted over the whole range of operation, based on the characteristics of each component. The predicted performance of the vacuum cleaner system through system-level analysis agreed well with the experimental results within 4.5% difference of pressure and 6% difference of the efficiency. The effect of flow resistance of a motor is investigated and it is found that the efficiency decrease of fan-motor assembly at the constant flow rate due to the flow resistance of a motor is determined by the flow resistance ratio(FRR), which is defined as a ratio of flow resistance of motor and the flow resistance of a constant throttling condition of a given point. The fan-motor assembly(S2 model) was modified to reduce the FRR from 9.0% to 2.4% and the experimental result shows that the efficiency of S2 model was improved by about 3% at best efficiency point.

Assessing Losers Consent in Mixed Systems: Public Perceptions of Taiwan’s 2008 Legislative Yuan Election

  • Rich, Timothy S.
    • Journal of Contemporary Eastern Asia
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    • 제15권1호
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    • pp.4-16
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    • 2016
  • A large literature identifies perceptual differences between citizens that support winning parties versus losing parties. These analyses fail to capture the complexity of mixed member legislative systems where one can be a winner or loser at both the national and district level. This paper proposes a two-level framework for the analysis of mixed system. An analysis of Taiwan’s first election under a mixed system provides evidence that both support for a national winner and district level winner produce boosts in positive perceptions of the electoral system. National success appears to be a larger motivator of perceptions.

다수준 실험계획법을 이용한 비정규 분포의 신뢰도 계산 방법 (Reliability Analysis for Nonnormal Distributions Using Multi-Level DOE)

  • 최현석;이상훈;곽병만
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2004년도 추계학술대회
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    • pp.840-845
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    • 2004
  • The reliability analysis for nonnormal distributions using the three level DOE(design of experiments) method was developed by Seo and Kwak in 2002. Although this method estimates only up to the first four moments(mean, standard deviation, skewness, and kurtosis) of the system response function, the result and the type of probability distribution determined by using the Pearson system are shown very good. However the accuracy is low in case of nonlinear performance function and sometimes, the level calculated is outside of the region in which the random variable is defined. In this article we suggest a modified three level DOE method to overcome these weaknesses and to obtain optimum choice for 3 levels and weights to handle nonnormal distributions. Furthermore we extend it to finding the optimum choice for 5 levels and weights to increase the accuracy in case of nonlinear performance function. A systematic procedure for reliability analysis is then proposed by using the Pearson system.

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The Analysis of Sulfur Compounds of Odorous Material in Kunsan Industrial Complex

  • Kim, Seong-Cheon;Kim, Ki-Hyun;Choi, Yeo-Jin
    • 한국환경보건학회:학술대회논문집
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    • 한국환경보건학회 2005년도 국제학술대회
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    • pp.399-405
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    • 2005
  • In this study, we investigated the gas chromatography (GC) and pulsed flame photometric detection (PFPD) system for the analysis of four major reduced S compounds including hydrogen sulfide ($H_2S)$; methyl mercaptan ($CH_3SH$); dimethyl sulfide (DMS); and dimethyl disulfide(DMDS) contained in environmental samples. To analyze these compounds in high concentration range (above ppb level), we developed a high mode analytical setting with the loop-injection system. By contrast, we also established a low mode setting for the analysis of low concentration samples (ppt-level samples from ambient air) by the combination with thermal desorption unit(TDU). Comparative analysis of both settings revealed that relative detection properties of four S compounds are systematic enough. The results of high mode analysis indicated that the patterns were systematic among compounds: H2S exhibited the lowest sensitivity, while DMBS showed the strongest one. The results were also compared in terms of sensitivity reductions for all compounds by dividing slope ratios between low and high mode system. Although low mode system exhibited significant reductions on the order of a few tens times, their detection characteristics were highly consistent as it was shown in the high mode setting. To learn more about absolute and relative relations between two different modes of S analysis, future studies may have to be directed to cover more complicated nature of GC/PFPD performance. Hydrogen sulfide($H_2S$) was over in summer about low level of olfactory sense 410 ppt, Methyl mercaptan(C$H_3SH$) was over in apring and summer about low level of olfactory sense 70, Dimethyl sulfide(DMS) was not over in four season about low level of olfactory sense 2,200 ppt. Carbon disulfide($CS_2$) was not over in four deason about Tow level of olfactory sense 210,000, Dimethyl disulfide(DMDS) was not over in summer about low level of olfactory sense2,000.

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