• Journal of Korean Institute of Industrial Engineers
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• v.34 no.4
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• pp.386-397
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• 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.

• Journal of East-West Nursing Research
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• v.10 no.1
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• pp.53-60
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• 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.

• Proceedings of the KSME Conference
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• 2000.11a
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• pp.141-146
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• 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.

• Journal of Ocean Engineering and Technology
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• v.24 no.6
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• pp.97-102
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• 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.

• Proceedings of the Korea Society of Environmental Biology Conference
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• 2004.05a
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• pp.62-62
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• 2004

• KIEAE Journal
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• v.10 no.3
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• pp.63-74
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• 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.

• Proceedings of the Korean Society of Embryo Transfer Conference
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• 2003.10a
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• pp.74-74
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• 2003

• Journal of Korean Society of Industrial and Systems Engineering
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• v.44 no.4
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• pp.98-105
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• 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.

• Journal of Digital Convergence
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• v.15 no.12
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• pp.293-301
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• 2017

Most new products not only suddenly disappear in the market but also quickly cannibalize older products. Under such a circumstance, retailers may have too much stock, and customers may be faced with difficulties discovering products suitable to their preferences among short life cycle products. To address these problems, recommender systems are good solutions. However, most previous recommender systems had difficulty in reflecting changes in customer preferences because the systems employ static customer preferences. In this paper, we propose a recommendation methodology that considers dynamic customer preferences. The proposed methodology consists of dynamic customer profile creation, neighborhood formation, and recommendation list generation. For the experiments, we employ a mobile image transaction dataset that has a short product life cycle. Our experimental results demonstrate that the proposed methodology has a higher quality of recommendation than a typical collaborative filtering-based system. From these results, we conclude that the proposed methodology is effective under conditions where most new products have short life cycles. The proposed methodology need to be verified in the physical environment at a future time.

• 유체기계공업학회:학술대회논문집
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• 1999.12a
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• pp.324-332
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• 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.