• 제목/요약/키워드: Short-life

검색결과 2,378건 처리시간 0.029초

Modeling and Evaluating Inventory Replenishment for Short Life-cycle Products

  • Wang, Ching-Ho;Lint, Shih-Wei;Chou, Shuo-Yan;Tsai, Chun-Hsiang
    • 대한산업공학회지
    • /
    • 제34권4호
    • /
    • pp.386-397
    • /
    • 2008
  • Due to the rapid advancement of technologies, a growing number of innovative products with a short life-cycle have been introduced to the market. As the life-cycles of such products are shorter than those of durable goods, the demand variation during the life-cycle adds to the difficulty of inventory management. Traditional inventory planning models and techniques mostly deal with products that have long life-cycles. The assumptions on the demand pattern and subsequent solution approaches are generally, not suitable for dealing with products with short life-cycles. In this research, inventory replenishment problems based on the logistic demand model are formulated and solved to facilitate the management of products with short life-cycles. An extended Wagner- Whitin approach is used to determine the replenishment cycle, schedules and lot-sizes.

중년여성의 건강증진을 위한 단기교육과 강화요법 프로그램의 효과 (The Effects of the Short Term Education and Reinforcement Program to Health Promotion in Women in Mid-life)

  • 김원옥;원정숙;현경선;한상숙;김귀분;이명희;박영미
    • 동서간호학연구지
    • /
    • 제10권1호
    • /
    • pp.53-60
    • /
    • 2004
  • The purpose of this study was to examine the effects of the short term education and reinforcement program to health promotion in women in mid-life. This study has been done between February and April, 2004 and the subjects of the study were 26 women in mid-life. The treatment intervention was applied during total 8 weeks as 5 days for the short term education and 7 weeks for reinforcement with 1 time per a week. The short term education included health education for menopause, effect of exercise, healthy diet, management of stress and management of chronic illness and stretching exercise and recreation. The collected data were processed using the SPSS Win(12.0) program and analyzed using Wilcoxon Signed Ranks Test. The result of this study are as follows : 1. The short term education and reinforcement program significantly effected on the total cholesterol, HDL-cholesterol, triglyceride. 2. The short term education and reinforcement program significantly effected on the anxiety, but not depression. 3. The short term education and reinforcement program non significantly effected on the sleep disturbance and self-efficacy of exercise. 4. The short term education and reinforcement program significantly effected on the practice of healthy life. In conclusion, the short term education and reinforcement program effected on the physical health index, anxiety and practice of healthy life.

  • PDF

짧은 피로균열의 랜덤하중하의 균열닫힘 및 진전거동(Part II : 진전거동 및 진전수명예측) (Crack Closure and Growth Behavior of Short Fatigue Cracks under Random Loading (Part II : Growth Behavior and Growth Life Prediction))

  • 이신영;송지호
    • 대한기계학회:학술대회논문집
    • /
    • 대한기계학회 2000년도 추계학술대회논문집A
    • /
    • pp.141-146
    • /
    • 2000
  • Crack closure and growth behavior of physically short fatigue cracks under random loading are investigated by performing narrow- and wide-band random loading tests for various stress ratios. The importance of the crack closure phenomenon is examined by predicting the growth lives of short cracks using obtained crack opening behavior. Artificially prepared two-dimensional, short through-thickness cracks are used. The crack opening load of short cracks is much lower under random loading than under constant-amplitude loading corresponding to the largest load cycle in a random load history. This result indicates that the largest load cycle in a random load history has an effect to enhance crack opening of short cracks. Most of the life prediction ratios are within the factor of 2 scatter band except several data at very short crack sizes, indicating that crack growth predictions based on the measured crack opening data are excellent. From the results obtained in this study, it can be concluded that crack closure is the primary factor governing fatigue crack growth of short cracks under random loading as well as under constant-amplitude loading.

  • PDF

스테인리스 강의 단시간 크리프 파단시간의 변동성과 수명예측 (Variability of Short Term Creep Rupture Time and Life Prediction in Stainless Steels)

  • 정원택;공유식;김선진
    • 한국해양공학회지
    • /
    • 제24권6호
    • /
    • pp.97-102
    • /
    • 2010
  • This paper deals with the variability of short term creep rupture time based on previous creep rupture tests and the statistical methodology of the creep life prediction. The results of creep tests performed using constant uniaxial stresses at 600, 650, and $700^{\circ}C$ elevated temperatures were used for a statistical analysis of the inter-specimen variability of the short term creep rupture time. Even under carefully controlled identical testing conditions, the observed short-term creep rupture time showed obvious inter-specimen variability. The statistical aspect of the short term creep rupture time was analyzed using a Weibull statistical analysis. The effect of creep stress on the variability of the creep rupture time was decreased with an increase in the stress level. The effect of the temperature on the variability also decreased with increasing temperature. A long term creep life prediction method that considers this statistical variability is presented. The presented method is in good agreement with the Lason-Miller Parameter (LMP) life prediction method.

장수명 공동주택의 관리자 유지관리 지침(I) (The Maintenance Guideline of Long-Life Housing for the Manager(I))

  • 지장훈;김수암;윤상조;정준수
    • KIEAE Journal
    • /
    • 제10권3호
    • /
    • pp.63-74
    • /
    • 2010
  • The general housing causes various environmental problems on the squandering of the resources and the production of the construction wastes, as it was removed and rebuilt because of the short-life in 20-30 years after constructing. The short-life of the general housing makes the rebuilt-term short and takes a negative attitude in maintenance. In the other hand, the long-life housing is constantly dwelling house that considers the carbon reduction among the world issues, Support and Infill. The long-life housing promotes the durability of Support and maximize the variability of Infill through separation of Support & Infill. It's useful dwelling house in maintenance as well as various life-cycle and life style. As the maintenance guideline of dwelling house is used for long-life housing, there is not distinction considering who controls maintenance and there is not conception considering alteration, variability and convenience. Consequently, it is required to develop the proper maintenance guideline applied maintenance process for long-life housing. Therefore this study shows efficient maintenance guideline for manager in long-life housing.

경기순환주기 소비위험과 한국 주식 수익률 횡단면 (Business Cycle Consumption Risk and the Cross-Section of Stock Returns in Korea)

  • 강한길
    • 산업경영시스템학회지
    • /
    • 제44권4호
    • /
    • pp.98-105
    • /
    • 2021
  • Using the frequency-based decomposition, I decompose the consumption growth to explain well-known patterns of stock returns in the Korean market. To be more specific, the consumption growth is decomposed by its half-life of shocks. The component over four years of half-life is called the business-cycle consumption component, and the components with half-lives under four years are short-run components. I compute the long-run and short-run components of stock excess returns as well and use component-by-component sensitivities to price stock portfolios. As a result, the business-cycle consumption risk with half-life of over four years is useful in explaining the cross-section of size-book-to-market portfolios and size-momentum portfolios in the Korean stock market. The short-run components have their own pricing abilities with mixed direction, so that the restricted one short-term factor model is rejected. The explanatory power with short- and long-run components is comparable to that of the Fama-French three-factor model. The components with one- to four-year half-lives are also helpful in explaining the returns. The results about the long-run components emphasize the importance of long-run component in consumption growth to explain the asset returns.

수명주기가 짧은 상품들에 대한 시퀀스 기반 개인화 서비스 (A sequence-based personalized service for the short life cycle products)

  • 최주철
    • 디지털융복합연구
    • /
    • 제15권12호
    • /
    • pp.293-301
    • /
    • 2017
  • 대부분의 신상품들은 시장에서 급격히 사라질 뿐만 아니라 기존 상품들의 매출감소를 불러온다. 이처럼 수명주기가 짧은 상품으로 인해 소매상들은 과다한 재고를 보유하게 될 뿐만 아니라 소비자들은 자신들의 선호를 맞는 제품들을 발견하는데 어려움을 겪는다. 이런 문제를 해결에 하는데 있어서 추천 시스템은 좋은 해결방법이 될 수 있다. 그러나 대부분의 추천 시스템들은 소비자의 고정된 선호를 이용하기 때문에 변화하는 소비자의 선호를 반영하지 못하는 문제가 있다. 이러한 문제를 해결하기 위하여 본 연구에서는 시간에 따라 변화하는 소비자의 선호를 반영한 추천 방법론을 제안하였다. 제안한 방법론은 소비자의 동적 선호 프로파일 작성, 네이버 형성, 추천 리스트 작성의 3 단계로 구성되어 있으며, 모바일 이미지 거래 데이터를 이용하여 제안된 방법론의 유용성을 검증하였다. 시험결과 제시된 방법론의 추천 정확도가 전통적인 협업필터링의 정확도 보다 높았다. 이러한 결과를 통해, 본 연구에서 제한한 방법론이 짧은 수명주기를 가진 제품을 추천하는데 효과적이라는 결론을 내릴 수 있다. 따라서 향후 제안된 방법론을 현업에 적용하여 실제적 유용성을 검증할 필요가 있다.

인공생명 알고리듬에 의한 고속, 소폭 저널베어링의 최적설계 (Optimum Design of High-Speed, Short Journal Bearings by Artificial Life Algorithm)

  • 이윤희;양보석
    • 유체기계공업학회:학술대회논문집
    • /
    • 유체기계공업학회 1999년도 유체기계 연구개발 발표회 논문집
    • /
    • pp.324-332
    • /
    • 1999
  • This paper presents the artificial life algorithm which is remarkable in the area of engineering for optimum design. As artificial life organisms have a sensing system, they can find the resource which they want to find and metabolize it. And the characteristics of artificial life are emergence and dynamical interacting with environment. In other words, the micro interaction with each other in the artificial life's group results in emergent colonization in the whole system. In this paper, therefore, artificial life algorithm by using above characteristics is employed into functions optimization. The effectiveness of this proposed algorithm is verified through the numerical test of single and multi objective functions. The numerical tests also show that the proposed algorithm is superior to genetic algorithm and immune algorithm for the Multi-peak function. And artificial life algorithm is also applied to optimum design of high-speed, short journal bearings and verified through the numerical test.

  • PDF