• 제목/요약/키워드: Quality Improvements

검색결과 1,105건 처리시간 0.032초

Effects of System Reliability Improvements on Future Risks

  • Yang, Heejoong
    • 품질경영학회지
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    • 제24권1호
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    • pp.10-19
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    • 1996
  • In order to build a model to predict accidents in a complicated man-machine sytem, human errors and mechanical reliability can be viewed as the most important factors. Such factors are explicitly included in a generic model. Another point to keep in mind is that the model should be constructed so that the data in a type of accident can be utilized to predict other types of accidents. Based on such a generic prediction model, we analyze the effects of system reliability. When we improve the system reliability, in other words, when there are changes in model parameters, the predicted time to next accidents should be modified influencing the effects of system reliability improvements. We apply Bayesian approach and finds the formula to explain how a change on the machine reliability or human error probability influences the time to next accident.

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대학도서관의 공간사용 실태에 관한 연구 (A Study on the Space Usages of Academic Libraries)

  • 안준석
    • 교육시설 논문지
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    • 제21권6호
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    • pp.25-32
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    • 2014
  • Korean academic libraries are facing serious space shortage problems due to an inability to accommodate for the rapidly increasing number of printed materials. Despite the current situation, Korean academic libraries have largely focused on impractical applications of the new library paradigm, using technology or management programs to improve the quality of research and learning environments of the university. However, such improvements would be fruitless without first resolving the space shortage crisis. In order to make realistic improvements to the quality of academic libraries, this study used questionnaires to employ the opinions of librarians currently practicing at such Korean libraries. Survey questionnaires about types and causes of space shortage problems, library facility expansion plans, expected effects of expansion, frequency of and reasons for furniture relocation, and tight spaces needing improvement were distributed to selected 4-year college librarians through Google Drive. Analysis of survey responses indicated that library space shortage was largely responsible for the hindrance of research and learning environments. Furthermore, it reflected the urgency to secure book storage space.

QFD를 활용한 가치요소 중심의 물류서비스 개선방안 (Improvements of logistics service focusing on value factors utilizing QFD)

  • 정용석;강경식
    • 대한안전경영과학회지
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    • 제19권4호
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    • pp.209-219
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    • 2017
  • Logistics companies want to be competitive companies in fierce logistics market and are worrying about securing of differentiated competitiveness for it. The standards judging if logistics industry maintains the competitiveness are based on the satisfaction of users due to the well-established service system that can response not only economic feasibility of logistics costs such as transportation costs, storage costs, unloading charges, information costs, etc. but also diversity and upgradability of logistics needs. Therefore, this study focuses on seeking of service quality improvements with VBSD(Value Based Service Design) model focusing on customer value factors based on Kano model and QFD based service design approach from angles of customer value improvement and service costs reduction.

홍채와 음성을 이용한 고도의 개인확인시스템 (Development of Advanced Personal Identification System Using Iris Image and Speech Signal)

  • 이대종;고현주;곽근창;전명근
    • 한국지능시스템학회논문지
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    • 제13권3호
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    • pp.348-354
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    • 2003
  • 본 논문에서는 홍채인식과 화자식별 방법을 결합한 고도의 개인확인 시스템을 제안한다. 제안된 방법은 홍채인식과 화자식별의 장점만을 부각시켜 최종적으로 결정법칙에 의해 화자를 인식하는 구조로 되어 있으며, 특히 음성에 노이즈가 첨가된 환경하에서도 우수한 성능을 보일 수 있도록 시스템을 구성하였다. 제안된 알고리즘의 성능을 검증하기 위하여 실험한 결과, 보안의 정도가 높은 상급(High)에 해당하는 인식률은 홍채만을 이용한 경우보다 56.7%, 음성을 이용한 화자식별 방법만을 사용한 경우보다 10% 정도 인식률이 향상되었다. 또한 음성에 노이즈를 첨가한 경우에도 보안의 정도가 높은 상급(High)에 해당하는 인식률은 홍채만 이용한 경우보다 인식률이 30%, 노이즈가 첨가된 음성만 이용한 경우보다 60% 정도 향상된 인식률을 보였다.

유한요소 기법을 활용한 설계검증 및 4M 변경점 관리를 통한 레이더장비 품질 신뢰성 확보에 관한 연구 (A Study on the Design Verification by Using Finite Elements Method and Quality Improvement of Radar by Managing Change Points of 4M)

  • 조희진;박세진;이남호;정원용
    • 품질경영학회지
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    • 제47권3호
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    • pp.437-451
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    • 2019
  • Purpose: The purpose of this study is to improve the quality of the PGM system by improving the structure and production process of slip-ring rotary joint for radar. Methods: The improvement measures for each cause are established through failure analysis of broken items. Specifically, changing in the housing to improve the heating system. Changing the transportation method to prevent damage to equipment during transport. Changing work process of the attenuator ring to prevent damage. etc. Results: The results of this study are as follows; improving the heating system reduces heat generated by the attenuator by about 7 degrees and obtain additional temperature margins. Reduction of defect rate because of adding X-band rotary joint run-out measurement test, ESS of slip-ring rotary joint and Transportation improvement(reinforced flight boxes, tube protection, etc). Getting stable VSWR values by improving work process of attenuator overheating due to a bad bonding process. Conclusion: Through this study, improvements were made to slip-ring rotary joint that failed repeatedly for various reasons. As a result of the application of the improvements, the same fault does not occur until now, so we can see that the quality of PGM has improved.

토양개량제 처리가 물푸레나무와 소나무 묘목의 생장과 양분농도에 미치는 영향 (The Effects of Soil Improvements on Growth and Tissue Nutrient Concentrations of Fraxinus rhynchophylla and Pinus densiflora Seedlings in a Nursery)

  • 박병배;변재경;조민석;한시호;정문호;김세빈;배기강
    • 한국환경복원기술학회지
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    • 제19권2호
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    • pp.41-54
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    • 2016
  • The production of high quality seedlings is a very important phase in silvicultural systems for successful reforestation or restoration. The purpose of this study was to measure both growth performances and nutrient responses of Fraxinus rhynchophylla and Pinus densiflora seedlings, which are commercially planted in Korea, according to soil improvement treatments. We applied 8 types of soil improvements: control with no treatment, compost B and compost Y as organic materials, vermiculite, perlite, two level of zeolite, and mix of vermiculite, perlite, and zeolite as inorganic materials in a permanent national nursery. Only compost B treatment significantly increased soil pH, organic matter, total nitrogen, available phosphorus, exchangeable potassium and calcium at the 0-10 cm soil depth. The growth of F. rhynchophylla and P. densiflora was the highest at the compost B treatment and the lowest at the vermiculate treatment. Compost B treatment allocated more carbon to aboveground than belowground by 39%, especially to foliage. On the vector diagnosis, there was 'shortage' on compost B treatment because of all increases of N contents, N concentrations, and growth and 'over accumulation' on vermiculite treatment because of more N uptake compared with dry weight increase. This study suggested optimal use of soil improvements is very important to improve soil quality in a permanently used nursery.

새로운 $TiSi_2$ 형성방법과 STI를 이용한 초박막 게이트 산화막의 특성 개선 연구 (Study of Improvement of Gate Oxide Quality by Using an Advanced, $TiSi_2$ process & STI)

  • 엄금용;오환술
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2000년도 추계종합학술대회 논문집(2)
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    • pp.41-44
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    • 2000
  • Ultra large scale integrated circuit(ULSI) & complementary metal oxide semiconductor(CMOS) circuits require gate electrode materials such as meta] silicides, titanium-silicide for gate oxides. Many previous authors have researched the improvements sub-micron gate oxide quality. However, little has been done on the electrical quality and reliability of ultra thin gates. In this research, we recommend novel shallow trench isolation structure and two step TiSi$_{2}$ formation for sub 0.1${\mu}{\textrm}{m}$ gate oxide.

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Experiences of Implementing TPM in Swedish Industries

  • Liselott Lycke;Akersten, Per-Anders
    • International Journal of Reliability and Applications
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    • 제1권1호
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    • pp.1-14
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    • 2000
  • The global marketplace is highly competitive and organisations, who want to survive long-term, have to continuously improve, change and adapt in response to market demands. These improvements should focus on cost cutting, increasing productivity levels and quality and guaranteeing deliveries in order to satisfy customers. Total Productive Maintenance (TPM) is one method, which can be used to achieve these goals. TPM is a change management approach that involves employees from both production and maintenance departments. The purpose is to eliminate major production losses by introducing a program of continuous and systematic improvements to production equipment. TPM should be developed and expanded to embrace the whole organisation and all employees should be involved in the process as members of improvement teams. This paper gives a short description of the development of TPM and the TPM implementation process. Findings are reported from a case study in which one of the authors had the possibility of following and guiding a company through their TPM implementation. The implementation process takes several years and the research has focused on the initial three years. The study demonstrates that driving forces, obstacles and difficulties often are dependent on the organisation, its managers and the individual employees.

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타이치 운동이 여성노인의 체력과 삶의 질에 미치는 효과 (Effects of Tai Chi Exercise on Physical Fitness and Quality of Life in Elderly Women)

  • 박정아;김숙영
    • 재활간호학회지
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    • 제17권1호
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    • pp.38-47
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    • 2014
  • Purpose: This study was performed to investigate the effects of Tai Chi exercise on physical fitness and quality of life (QOL) in elderly women. Methods: This study was designed as a quasi-experimental, nonequivalent control group pre-post test design. The subjects were elderly women over 60 years old who enrolled senior citizen centers and elderly welfare center. Thirty-three people were conveniently assigned to an experimental group (n=15) or a control group (n=18). The data were collected from September 2009 to May 2010. The experimental group was trained Tai Chi exercise for 8 weeks (one hour Tai Chi classes twice a week and once a week by themselves at home). Data were analyzed by Fisher's exact test, ${\chi}^2$-test and independent t-test. Results: The experimental group experienced significant improvements in flexibility. The experimental group experienced significant improvements in physical component summary (p=.017) and mental component summary (p=.027) of QOL. Conclusion: Tai Chi exercise can be used as a nursing intervention for improvement of physical fitness and QOL in elderly women.