• 전기학회논문지
• /
• 제60권11호
• /
• pp.2176-2181
• /
• 2011

This paper estimates the life cycle cost(LCC) of a propulsion control system using the maintenance information in the high speed train(KTX-1). Life cycle costing is one of the most effective approaches for the cost analysis of long-life systems such as the KTX-1. Until now, most life cycle cost of the system has been studied as a whole system viewpoint. But in case of railway industry, LCC studies are needed on the subsystem like a propulsion control system because subsystems are developed continuously localization. This paper proposes the life cycle cost model which fitted to estimate life cycle cost (LCC) using maintenance information manual. As a result, LCC on propulsion control system increased moderately expect for periodical time when major parts are replaced at the same time. Results will be reflected in the development of domestic products.

• 전기학회논문지
• /
• 제62권2호
• /
• pp.288-292
• /
• 2013

This paper presents the result of life-cycle cost (LCC) estimation for domestic products propulsion control system (motor block unit) of KTX-1 considering periodic maintenance. Life cycle costing is one of the most effective approaches for the cost analysis of long-life systems such as the KTX-1. Life cycle costing includes the cost of concept design, development, manufacture, operation, maintenance and disposal. To estimate LCC for domestic products motor block unit, it was analyzed physical breakdown structure (PBS) on motor unit in view of maintenance cost and unit cost etc. As a results, life cycle cost on motor block unit increased moderately expect for periodical time when major parts are replaced at the same time. hereafter this results will be reflected in the domestic products being developed.

• 비파괴검사학회지
• /
• 제28권6호
• /
• pp.512-518
• /
• 2008

Guided wave technology is advantageous for fast inspection of pipe wall thinning since the guided wave propagates long distance. In this investigation, the method to evaluate gradual wall thinning in a pipe based on the arrival time delay with magnetostrictive patch transducers is presented. Low frequency A0 Lamb waves were generated and measured by the present transducer and it was applied to arrival time delay measurement experiments on a test pipe having gradual wall thinnings artificially manufactured. From experiments, consistent results that wall thinning increases the arrival time delay of A0 waves were obtained. Consequently, the feasibility of the magnetostrictive patch transducers to evaluate wall thinning was verified.

• 한국경제지리학회지
• /
• 제17권4호
• /
• pp.759-770
• /
• 2014

본 논문은 시간의 제약이 활동 및 통행으로 연결됨을 확인하는 것이 목적이며, 이를 위해 우리나라 수도권 전일제 근로자의 평일 시간이용에 집중하였다. 특히, 우리나라의 근로자는 다른 OECD 국가의 근로자보다 근로시간에 할애하는 시간이 압도적으로 많다. 이로 인해 나타나는 시간부족현상은 긴 근로 시간으로 인해 근로 외 활동에 제약이 생기는 문제가 나타날 수 있다는 차원에서 삶의 질 문제를 논의해볼 수 있다. 이와 같은 배경에서, 수도권에 거주하는 전일제 근로자의 시간 제약이 활동 및 통행 제약에 영향을 끼치는지 확인하기 위해 2010 가구통행실태조사의 수도권 자료를 활용하여 통행사슬(trip-chain)을 구성하였으며, 이를 유형별로 구분하고 유형에 따른 시간이용패턴을 분석했다. 그 결과, 시간부족현상이 전반적인 활동의 제약으로 나타났으며, 이는 활동패턴에 영향을 끼치는 것으로 나타났다. 본 논문은 근로시간 및 교통에 관련된 정책 대안에 함의를 가지고 있으며, 향후 활동기반 관점의 삶의 질 측정에 도움이 될 것으로 생각된다.

• 보험의학회지
• /
• 제30권2호
• /
• pp.16-19
• /
• 2011

In patents with diabetes, the higher the serum glucose level was, the more cardiovascular events and death were observed. But with a certain kind of group, to control glucose level tightly does not decrease the incidence of these events. Several studies show that intensive glucose control does not gain benefit in patient with long standing, uncontrolled diabetes, especially having previous cardiovascular events, while definitely preventing progression of newly onset of diabetic nephropathy. Whether intensive glucose control increases mortality in high risk group is obscure and needs more studies with longer observation time.

• 한국해양공학회:학술대회논문집
• /
• 한국해양공학회 2001년도 춘계학술대회 논문집
• /
• pp.108-113
• /
• 2001

In this paper, the real-time prediction of high temperature creep strength and creep strength and creep life for nickel-based superalloy Udimet 720 (high-temperature and high-pressure gas turbine engine materials) was performed on round-bar type specimens under pure load at the temperatures of 538, 649 and 704$^{\circ}C$. The predictive equation of ISM creep has better reliability than that of LMP and LMP-ISM, and its reliability is getting better for long time creep prediction(10$^3$~10sup/5/ｈ).

• 한국신뢰성학회지:신뢰성응용연구
• /
• 제11권3호
• /
• pp.267-279
• /
• 2011

LEDs have been used extensively in the mobile device, automobile, and general lighting because they are semi-permanent, long life, less power consumption, reliable and environmentally friendly. In this paper, the accelerated degradation test(ADT) for a general lighting 4W LED Lamp using external converter is considered. The conditions of ADT are high temperature and high humidity. We show that its life time is log-normally distributed with same parameters under both a normal condition and an accelerated condition, and also derive an accelerated factor.

• The Plant Pathology Journal
• /
• 제33권2호
• /
• pp.103-108
• /
• 2017

World wheat production is now under threat due to the wheat blast outbreak in Bangladesh in early March 2016. This is a new disease in this area, indicating the higher possibility of this pathogen spreading throughout the Asia, the world's largest wheat producing area. Occurrence of this disease caused ~3.5% reduction of the total wheat fields in Bangladesh. Its economic effect on the Bangladesh wheat market was little because wheat contributes to 3% of total cereal consumption, among which ~70% have been imported from other countries. However, as a long-term perspective, much greater losses will occur once this disease spreads to other major wheat producing areas of Bangladesh, India, and Pakistan due to the existing favorable condition for the blast pathogen. The wheat blast pathogen belongs to the Magnaporthe oryzae species complex causing blast disease on multiple hosts in the Poaceae family. Phylogenetic analysis revealed that the Bangladesh outbreak strains and the Brazil outbreak strains were the same phylogenetic lineage, suggesting that they might be migrated from Brazil to Bangladesh during the seed import. To protect wheat production of Bangladesh and its neighbors, several measures including rigorous testing of seed health, use of chemicals, crop rotation, reinforcement of quarantine procedures, and increased field monitoring should be implemented. Development of blast resistant wheat varieties should be a long-term solution and combination of different methods with partial resistant lines may suppress this disease for some time.

• 한국임상약학회지
• /
• 제27권4호
• /
• pp.199-206
• /
• 2017

As the population ages, the life of women after menopause becomes much longer than the past, and the quality of life of old age becomes increasingly principal issue. There is a period that women experience the physical symptoms of menopause, although there are differences in degree, and the management of this period is a suitable time for women to improve their quality of life. According to the menopausal hormone therapy (MHT) and Timing Hypothesis, which has been proven in the Kronos Early Estrogen Prevention Study (KEEPS) and the Early vs Late Intervention Trial with Estradiol (ELITE) study, a relatively young woman before and after menopause can benefit from long-term beneficial effects such as prevention of osteoporosis and cardiovascular disease by early initiation of hormone therapy to alleviate menopausal symptoms. MHT should be considered for all women in healthy (without other important diseases) menopausal years, expecting to improve their quality of life through symptom relief in menopausal women and, in the long term, to prevent cardiovascular disease and osteoporosis. When applying hormone therapy to individuals, it is necessary to establish various treatment strategies according to the menopausal symptoms of individual patients (individualization of treatment) and judge the suitability of clinical application.

• 대한기계학회논문집A
• /
• 제31권2호
• /
• pp.160-165
• /
• 2007

To predict long-term creep life from short-term creep life data, various parametric methods such as Larson-Mille. (L-M), Orr-Sherby-Dorn (O-S-D), Manson-Haferd (M-H) parameters, and a Minimum Commitment Method (MCM) were suggested. A number of the creep data were collected through literature surveys and experimental data produced in KAERI. The polynomial equations for type 316LN SS were obtained by the time-temperature parameters (TTP) and the MCM. Standard error (SE) and standard error of mean (SEM) values were obtained and compared with the each method for various temperatures. The TTP methods showed good creep-life prediction, but the MCM was much superior to the TTP ones at $700^{\circ}C$ and $750^{\circ}C$. It was found that the MCM were lower in the SE values when compared to the TTP methods.