• 제목/요약/키워드: Inventory control system

검색결과 255건 처리시간 0.032초

채찍효과에 대한 트리즈 분석과 연구현황 고찰 (TRIZ Analysis to Bullwhip Effect and a Survey on Studies)

  • 송창용
    • 산업경영시스템학회지
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    • 제39권3호
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    • pp.109-117
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    • 2016
  • Recently, corporate environment is faced with uncertainty that did not suffer in the past. In addition, as the supply chain was expanded and lengthened, the flow of information and material was complicated. Increase in complexity which amplifies the variability of the individual steps in supply chains further adds to the uncertainty. The bullwhip effect that refers the phenomenon where order variability increases as the orders move upstream in the supply chain became serious. The bullwhip effect is more and more important especially for the enterprise in the supply chain. So, there are many studies now since it was observed about 100 years ago. The aim of this paper is to analyze how to solve the bullwhip effect by using TRIZ (Teoriya Resheniya Izobretatelskikh Zadach). TRIZ is one of the most famous tools for creative solving that applied in many fields ranging from management as well as engineering. Among problems, the dilemma needs creative solutions that require handling the contradictions inherent in that. Among various kinds of problem solving techniques, TRIZ provides the concept of physical contradiction as a common problem solving principle. This study provides a simple process of solving problem explains a case of solving problem in the management field and shows the availability of theory in the inventory control. In accordance with the proposed solving process, the paper analyzes the bullwhip effect by applying the TRIZ tools and then identifies the solution directions. Next, the current studies are classified by the above analysis and important managerial concepts are proposed. Lastly, directions for future research on this area are suggested.

2007년 6월 수도권 오존모사 I - 광화학측정자료를 이용한 SAPRC99 화학종별 휘발성유기물질 배출량 입력자료 평가 (Ozone Simulations over the Seoul Metropolitan Area for a 2007 June Episode, Part I: Evaluating Volatile Organic Compounds Emissions Speciated for the SAPRC99 Chemical Mechanism)

  • 김순태
    • 한국대기환경학회지
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    • 제27권5호
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    • pp.580-602
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    • 2011
  • Volatile organic compound (VOC) emissions in the 2007 CAPSS (Clean Air Protection Supporting System) emissions inventory are chemically speciated for the SAPRC99 (Statewide Air Pollution Research Center 99) mechanism, following the Source Classification Code (SCC) matching method to borrow the U.S.EPA's chemical speciation profiles. CMAQ simulations with High-order Direct Decoupled Method (HDDM) are in turn applied to evaluate uncertainty in the method by comparing the simulated model VOC species to the observations in the Seoul Metropolitan Area (SMA) for a 2007 June episode. Simulations under-predicted ALK1 to ALK4 in SAPRC99 by a factor of 2 to 5 and over-predicted ALK5 by a factor of 7.5 while ARO1, ARO2, OLE1, and ethylene (ETH) are comparable to the observations, showing relative difference by 10 to 30%. OLE2 emissions are roughly 4 times overestimated. Emission rates for individual VOC model species are revised referring to the ratio of simulated to observed concentrations. Impact of the VOC emission changes on the overall ozone prediction was insignificant for the days of which 1-hr maximum ozone are lower than 100 ppb. However, simulations showed ozone difference by 5 to 10 ppb when high ozone above 120 ppb was observed in the vicinity of Seoul. This result suggests that evaluations on individual model VOC emissions be necessary to lead ozone control plans to the right direction. Moreover, the simulated ratios of ARO1 and ARO2 to $NO_x$ are roughly 50% lower than the observed ones, which imply that adjustment in $NO_x$ and VOC emission rates may be required to mimic the real VOC/$NO_x$ condition over the area.

Brief history of Korean national forest inventory and academic usage

  • Park, Byung Bae;Han, Si Ho;Rahman, Afroja;Choi, Byeong Am;Im, Young Suk;Bang, Hong Seok;So, Soon Jin;Koo, Kyung Mo;Park, Dae Yeon;Kim, Se Bin;Shin, Man Yong
    • 농업과학연구
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    • 제43권3호
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    • pp.299-319
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    • 2016
  • The National Forest Inventory (NFI) is important for providing fundamental data for basic forest planning and the establishment of forest policies for the purpose of implementing sustainable forest management. The purpose of this study is to present the development of Korea's NFI including legal basis, sampling design, and measured variables and to review the usage of NFI data. The survey methods and forestry statistics among the Unites States, Canada, Japan, China, and European countries were briefly compared. Total 140 publications utilizing NFI data between 2008 and 2015 were categorized with 15 subjects. Korea has conducted the NFI 6 times since 1971, but only the $6^{th}$ NFI is comparable with the fifth, the previous NFI, because the permanent sampling plots have been shared between the periods. The Korean Forestry Statistics contains only half as many variables as that of advanced countries in Forestry. More researches were needed to improve consistent measurement of diverse variables through implementation of advanced technologies. Additional data for Forest Health Monitoring since the NFI $6^{th}$ must be under quality control which will be an essential part of the inventories for providing the chronological change of forest health.

호텔 종사자들에서 불안 및 우울과 24시간 활동혈압 관련성 (The Relationship between Anxiety, Depression and 24-hour Ambulatory Blood Pressure in Hotel Employees)

  • 배준호;사공정규;김상규
    • 농촌의학ㆍ지역보건
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    • 제36권3호
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    • pp.157-166
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    • 2011
  • 이번 연구는 일개 사업장 근로자를 대상으로 24시간 활동혈압에 따른 고혈압군과 정상군의 불안과 우울정도를 비교하고 불안증상과 우울증상에 따른 혈압 양상을 비교 분석하고자 하였다. 일개 사업장 근로자 107명을 대상으로 2009년 12월 10일부터 2010년 3월 20일까지 사업장을 방문하여 BAI와 BDI로 불안과 우울정도를 조사하였고 임상혈압과 24시간 AMBP로 활동혈압을 측정하였다. 임상혈압과 24시간 AMBP에서 고혈압군과 정상군의 BAI와 BDI 점수는 모두 유의한 차이가 없었지만, 우울증상군에서 정상군보다 야간 이완기혈압 비강하 발생위험도가 6.85배 (CI 1.50-30.01)높았다. 고혈압 치료를 시작하거나 치료 중인 환자에서 치료순응율을 향상시키고 심혈관계 질환 예방을 위해서는 심리적인 중재도 필요하다고 판단되어진다.

3차진료기관 외래약국 투약대기시간에 영향을 주는 요인 (Factors Affecting Patient Waiting Times at the Outpatient Pharmacy Department in a Tertiary Care Hospital)

  • 박하영;한옥연;나현오
    • 한국의료질향상학회지
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    • 제1권2호
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    • pp.60-72
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    • 1994
  • Background: The number of outpatients visiting large university teaching hospitals has increased drastically with the introduction of a nationwide health care insurance in 1989 and the improvement of the socio-economic status of the population. This resulted in long waiting times for services, particularly prescribed drugs, which have been patients' chief complaints. Hospitals have tried to solve the problem with limited success because their approach lacked comprehensive research. The objective of this study is to investigate associations between waiting times and variables defining a total work system. Methods: Data for the outpatient pharmacy department in a tertiary care university teaching hospital located in Seoul was analyzed to achieve the study objective. Associations of pharmacy system variables -- work load, work force, pharmacist work schedule, machine problems, and inventory control -- with mean and 99th percentile of waiting times were examined by the hierarchical stepwise regression method. Day was a unit of the analyses. Results: The regression models explained 65.8% of variance in the mean waiting time and 61.34% in the 99th percentile of waiting times. The break-down of the printer for drug envelops, Automatic Tablet Counters (ATCs), and main computer system lasted longer than 30 minutes increased the mean for 7.7 minutes, 4.5 minutes, and 7.0 minutes, respectively, and the 99th percentile for 14.8 minutes, 9.0 minutes, and 15.7 minutes, respectively. Concerning the work force, study results showed that there were significant differences in the productivity of pharmacists with work experience more than three years, one to three years, and less than one year, and showed that peak time aid work by pharmacists at job assignments other than the outpatient pharmacy, part-time pharmacists, and the installation of ATCs were effective in reducing waiting times, Finally, study findings indicated that the operational policy of work assignment and rotation schedule, supply and inventory of drugs at work tables, and readiness for undisrupted work during the work hours could have a significant effect on waiting times. Conclusion: The study results indicated that efforts to reduce waiting times for prescribed drugs should be geared toward every components of the pharmacy work system ranging from work schedule of pharmacists and supply of dugs at work tables. These findings should provide hospital managers with right directions in battling the problem.

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아로마 흡입요법이 요역동학검사 환자의 불안과 심박변이도에 미치는 효과 (The Effects of Aroma Inhalation Therapy on Anxiety and Heart Rate Variability in the Patients Undergoing Urodynamic Study)

  • 김명완;유양숙;조옥희;조성준
    • Journal of Korean Biological Nursing Science
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    • 제11권1호
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    • pp.32-41
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    • 2009
  • Purpose: This study was to identify the effects of aroma inhalation therapy on heart rate variability and anxiety in the context of urodynamics study. Method: The data were collected from 64 patients who were receiving urodynamics at the C University Medical Center in Seoul, 23 in the experimental group, 22 in the placebo group and 19 in the control group. In the experiment, the subjects of the experimental group inhaled a mixture of lavender and bergamot for 5 min, the subjects of the placebo group inhaled geranyl acetate oil for 5 min and the subjects of the control group relaxed for 5 min. The instruments used in this study included the state anxiety inventory and heart rate variability. Result: The score of state anxiety was no significant differences between the three groups after aroma-inhalation. Also, the sympathetic nerve activity and parasympathetic nerve activity was no significant differences between the three groups after aroma-inhalation. Autonomic nerve balance was maintained significantly in the experimental group as compared to the control groups after aroma-inhalation. Conclusion: The aroma inhalation therapy was very effective in balancing the autonomic nervous system in the patients undergoing urodynamic study.

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영미계목록규칙 발전의 사적 고찰 (A Historical Study on the American-British Cataloging Rules)

  • 심의순;손문철
    • 한국도서관정보학회지
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    • 제11권
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    • pp.143-173
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    • 1984
  • This study has been done to review the historical development of the cataloging system of books with emphasis on those in England and the U. S. The findings can be summarized as follows: (1) In 1844, Sir Panizzi invented what seems to be the first of its kind in history to list the inventory systematically at the British Museum. It is believed to be a complete system consisting of 91 articles. (2) A comparatively systematic system was developed in America by Jewett. in 1852. Composed of only 39 articles, the system is considered a renovative one worked out with due regard to the infrastructure of a library. (3) In 1876, a classic system based on a lexicographical order was set up by Cutter. Rated as the best one that was designed by an individual, the theory has since exercised widespreading effects on cataloging. (4) American and British library scientists collaborated in printing several editions of numerous volumes on the principles of classification, but they are not believed fully successful in establishing a consistent and compressive system. Their efforts found significance rather in their being the first international collaboration and setting a foundation upon which the international system of today has been developed. (5) The ALA Rule, published concurrently in ALA and LC in 1949, had two parts in its classification, the list of authors and that of titles. Its scientific classification has completed the cataloging of books in its developmental stage. (6) The 1967 American-British Rules integrated the cataloging systems published under separate covers by authors and titles. The system as well as the 1961 Paris System has greatly contributed to the standardization of bibliographical description throughout the English-speaking countries. The International Standard Book Description standardized Bibliographic system has enabled the librarians in different countries to exchange their bibliographical sources easily, helped to overcome the language barrier in listing and contributed to the efficient reading of bibliographical records through machines. (7) The second edition of the Angelo-American cataloging Rules, promulgated in 1978 under the influence of the international standard bibliographical description, was the one in which all the previous Rules were revised to have their strong points. The adoption of punctuation system to employ the computerized data processing and the standardization of description are expected to improve the cataloging system not only in the English speaking countries but in the Universal Bibliographic Control as well.

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중증 장애인을 위한 생활환경 제어장치개발에 관한 연구 (A Study on Development of ECS for Severly Handicaped)

  • 임동철;이행세;홍석교;이일영
    • 대한의용생체공학회:의공학회지
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    • 제24권5호
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    • pp.427-434
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    • 2003
  • 본 논문은 음성기반 생활환경 제어장치 (Enviropmet Control System: ECS)의 개발과 적용에 대해 다룬다. 구체적으로 개발 내용은 음성인식을 통한 생활환경의 제어 장치와 음성 지원 이동형 휠체어 리프트 제어장치를 구현하였다. 구현된 시스템은 경수 손상 사지마비 환자에게 적용되었고 활용의 문제점과 장치의 사용이 장애인 및 가족에게 미치는 신체적 정신적 영향을 평가 고찰하였다. 음성 인식 시스템은 HMM기반 실시간 음성 인식 시스템을 구성하였고 임상의 적용을 평가하기 위하여 가전 기구를 제어하도록 간략화된 음성인식 모듈을 구현하여 54세 남자로 완전 제 4 경수 손상인을 대상으로 1주간 관찰하였다. 그리고 설문 조사를 통하여 Beck 우울 척도와 오락 및 사회적 관계성의 변화를 평가하였다. 또한 음성 지원 이동형 휠체어 리프트의 전동기 구동 제어 장치를 개발하고 구조 역학 해석을 통해 기계적 안정성을 평가하고 시제품을 제작 성능 시험을 하였다. 시스템의 실험 결과 95%이상의 인식률을 나타내었다. 설문조사 결과 장애인의 장치에 대한 만족도는 높은 편이고 간호의존도와 사회적 관계성의 증진을 확인할 수 있었다. 이에 더불어 간병인의 부담과 우울 경향의 감소가 있었다. 또한 음성 지원 이동형 휠체어 리프트는 구조 해석 결과, 상단 휠체어 바퀴 지지대의 재료로서의 피로 수명이 우수하고 무게 중심 이동이 안정성을 가짐을 확인하였다. 본 논문은 실시간 음성 인식 시스템과 이동형 휠체어 리프트를 이용한 장애자를 위한 생활환경 제어장치 구성의 한 예를 제시하였고, 실험을 통하여 실시간 음성인식의 중요한 활용 분야인 재활 의학 분야에서 한국형 생활환경 제어장치의 개발의 필요성을 확인하였으며 상용화를 모색의 발판이 될 것이다.

Investigation on How VMI affects Ongoing Performance of Supply Chain System

  • RYU, Chungsuk
    • 유통과학연구
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    • 제18권1호
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    • pp.85-94
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    • 2020
  • Purpose: This study investigates the influence of VMI on the supply chain performance over time. By examining each supply chain member's ongoing performance, this study figures out how VMI allows the vendor to overcome the initial loss and eventually provides the benefit to every supply chain member. Research design, data, and methodology: The proposed mathematical model describes the supply chain system where a manufacturer and a retailer make the operational decisions to maximize their own profits. By using the numerical examples with arbitrary data, VMI and non-VMI are compared in terms of their profit changes over time. Results: The numerical analysis shows that VMI results in greater overall profits for both manufacturer and retailer than non-VMI, while the manufacturer make a loss in the early stage of VMI implementation. This study also examines the impacts of certain conditional factors on the performance of VMI. Conclusions: This study supports the idea that VMI leads to manufacturer's initial loss but it brings greater profits to both manufacturer and retailer than non-VMI after all. In addition, the result of this study provides the managerial implications about the particular condition that allows VMI to achieve a significant financial performance improvement over non-VMI.

전동차 환경성 진단용 RACE프로그램의 주요기능 (Main Function of RACE Software for Environmental Assessment of Electric Motor Unit)

  • 김용기;이재영;서민석;최요한
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2007년도 춘계학술대회 논문집
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    • pp.1244-1249
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    • 2007
  • Pursuing sustainable development throughout society and industry and the field of environmental policy, each international organization or nation has performed international standardization projects on environmental management activities for their system as well as environmental assessment for a product such as life cycle assessment (LCA) and life cycle inventory database (LCI DB), and the environmental aspects have been increasingly demanded as crucial evaluation specifications. Moreover, the conventional environmental policy, which represents the direct-control, has been more dependent on the market forces and product itself after the Climate Change Convention., and the Integrated Product Policy (IPP, EU) is applied vigorously to strengthen global competitiveness of a product and to achieve the effect of environmental improvement for it. According to change of the international railway market, the value of Eco-Design has been increasingly important in developed countries including EU. Thus, each country is establishing its own guidelines, software and database for each product, and developing new policies through Eco-Design with practical results in marketing. To react this and develop Korean railway as an environment-friendly industry with priority to other transportation system as well as maintain high place in technology, the direction of RACE software development of main function is introduced, which is exclusively used for EMU to assess both environmental and economic aspects with LCA and eco-efficiency (EE).

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