• Title/Summary/Keyword: life-time use

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Dynamic Performance of Geotextile Container under the Simulated Cyclic Train Loading (모사반복 열차하중 재하시 토목섬유 콘테이너의 동적 성능)

  • Hwang Seon Keun;Koh Tae Hoon;Park Sung Hyun;Choi Chan Yong
    • Proceedings of the KSR Conference
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    • 2003.10b
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    • pp.92-97
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    • 2003
  • Roadbed failure due to the rainfall may bring out social and economic demage such as the loss of life and property, the consumption of time and cost for recovery, and the delay of logistics in railway. In this study, the method using Geotextile Container was applied to rehabilitation of the railway roadbed which was failed by rainfall. The real scale tests with the simulated train loading were performed in order to evaluate the dynamic performance at the railway roadbed using Geotextile Container. The results of these tests were compared with unreinforced and reinforced cases with Geotextile Container, respectively. The data gathered by various measurement devices from these real scale tests would be useful to evaluate and understand the roadbed with Geotextile Container. Furthermore, the results of this study would be useful to ensure the workability and to save much time for restoration and to be widely applied to practical use.

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A Study on the Cold Weather Concrete using High Early Strength Concrete (조강시멘트를 이용한 한중콘크리트의 특성평가 연구)

  • 임채용;엄태선;유재상;이종열;이순기;이동호
    • Proceedings of the Korea Concrete Institute Conference
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    • 2003.11a
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    • pp.261-264
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    • 2003
  • Cold weather can lead to many problems in mixing, placing, setting time, and curing of concrete that can have harmful effects on its properties and service life. Korean Concrete Institute (KCI) defines cold weather as a period when the average daily air temperature is less $4^{\circ}C$ and recommends to cast concrete with special care such as shielding, heating and so on. The use of high early strength cements may improve the rate of hardening characteristics of concrete in cold weather by making it possible to achieve faster setting time and evolving more hydration heat than ordinary Portland cement. Higher early strength can be achieved using Type III cement especially during the first 7 days. The strength increase property of Type III cement at low temperature was studied. As a conclusion the heat or heat insulation curing period can be reduced to 50~75%. So, it can be used for cold weather concreting to reduce construction cost and extend the construction season.

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A Case Study on the Family-Friendly Firm Workers' Flexibility Needs (근로자들의 근무유연성에 대한 요구 분석 - 한 가족친화인증기업 근로자들의 사례 -)

  • Lee, Hyun-Ah;Kim, Seon-Mi;Lee, Seung-Mi
    • Journal of Family Resource Management and Policy Review
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    • v.15 no.2
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    • pp.63-84
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    • 2011
  • This qualitative case study focused on the workers' flexibility needs. We selected eight full-time workers from one 2009 family friendly certified firm for observation and in-depth interview. The workers are categorized into three groups; male employees with housewives, double income family workers depending on extended family, and double income family workers depending on paid babysitter. The spouse's work status and informal extended familial support to child care were crucial factors to influence their work family life styles and flexibility needs. The flex time is the most desirable everyday needs for the dual working child caring parents depending on the paid help. And the female workers' concerned about the stigma effect of the institutionalized flexibility use of the inferior labors.

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A Study on the Attitude and the Actual Condition between Housewives and Woman University Students about Furniture Usage and Living Room (거실공간과 가구사용에 대한 주부와 여대생의 의식 및 실태)

  • 임소연
    • Journal of the Korean Home Economics Association
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    • v.33 no.4
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    • pp.289-300
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    • 1995
  • The purpose of this study was to suggest usage that all family members could find satisfaction in the way to use furniture and living room. First of all, methods of research for this purpose were to grip on the points of difference and sameness on the attitude and the actual condition about furniture usage and living room between housewives and woman university students. To make analysis the data, frequency, $\chi$2-test, t-test, F-test and factor analysis were used. The major results are as follows ; 1. There were significant differences in the using time, time zone and life behavior in living room. 2. In furniture usage, housewives and woman university students have significant differences. 3. According to the results of making investigation into degree of satisfaction abut furniture and living room usage, housewives and woman university students have significant differences.

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Study on the Effective Operating Method of on-off Valves for a Pneumatic Servo System (개폐식 밸브를 사용한 공기압 서보 시스템의 효율적 밸브 개폐 방법에 관한 연구)

  • 황웅태;최서호;이정오
    • Journal of the Korean Society for Precision Engineering
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    • v.15 no.1
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    • pp.109-116
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    • 1998
  • This paper is concerned with effective operating method of pneumatic on-off valves for improving position control accuracy, valve life-time and position settling time using modified pulse width modulation with dead-zone (MPWMD). The pneumatic system using on-off valves has advantage of simple construction and low cost compared with a system with servo-valves. The performance of the proposed control method is investigated experimentally for the position control of a pneumatic cylinder using on-off valves. Experimental results show that the proposed algorithm for valve operation can be used to obtain fast and accurate position control compared to the conventional PWMD algorithm. It is also shown that the use of the proposed MPWMD algorithm for the position control significantly reduces the number of valve switching and noise.

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Study on assessment of the environmental impacts for track system by Input-Output Analysis (산업연관분석법에 의한 궤도시스템의 환경부하 평가)

  • Kim, Yong-Ki;Lee, Cheul-Kyu;Jeon, Yong-Sam;Jo, Hyun-Jung
    • Proceedings of the KSR Conference
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    • 2009.05a
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    • pp.73-76
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    • 2009
  • LCA is nowadays getting popular as a tool to assess the environmental impacts. We can assess the environmental impacts of products and also compare the environmental performance between products with LCA. Furthermore, the LCA results can be used for designing eco-friendly products. But LCA needs an enormous amount of data collection, calculations of energy and material balance. which required to spend pretty much time and cost. However, If we use Input-Output Analysis, There is a lot of advantages that we can save time and cost to calculate and also analyze energy-material balance more comprehensively. Therefore, we implemented the fundamental research of the environmental impact assessment on railway system using life cycle inventory analysis and Input-Output Analysis method.

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A Study on Evaluation of Optimal Replacement Period by Reliability Prediction for the Door Control Relay of EMU (전동차 출입문제어 계전기의 신뢰도예측을 통한 적정 교체주기 연구)

  • Han, Jaehyun;Kim, JongWoon;Koo, JeongSeo
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.28 no.7
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    • pp.34-40
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    • 2014
  • In this paper, we want to know the optimal replacement cycle(time) for this study was performed. The optimal preventive replacement age can be fond by finding the value of time that minimizes the cost function(model of Barlow and Jardine). In addition, The reliability of the relay according to the service environment were studied. The use of the exchange relay period is longer, and maintenance cost rate(per hour) may increase, and also the reliability may cause a decline. In addition, considering the preventive maintenance and purchase order, a representative relay(RAX-L440-A type) life was calculated.

Effect of Loess Bedding with Loess Nanoparticles on Sleep Disorder (황토나노입자를 부착한 황토이불 사용이 수면장애에 미치는 효과)

  • Lee, Ku Yeon;Hahm, Suk Chan
    • Journal of Naturopathy
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    • v.11 no.1
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    • pp.9-17
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    • 2022
  • Background: No studies have reported on the effects of loess beddings on insomnia patients. Purpose: It studied the change in quality of life and quality of sleep after having 15 insomnia subjects use the bedding that emits far-infrared rays. Methods: After using loess bedding for the test group and general yellow bedding for the control group, the study was conducted in the form of a questionnaire on the WHO quality of life of the subjects. Results: In the overall quality of life evaluation, the pre-and post-changes significantly improved in the test group. Using loess bedding was greatly enhanced the physical change, the actual sleep time, and the quality of sleep of the test group. The period of sleep was significantly longer post-treating, and the habitual sleep efficiency was considerably higher, and sleep disturbance was significantly lower than before in the test group. Sleep drug use and daytime dysfunction after treating in the test group significantly improved the sleep effect. Changes in the Sociality Scale, Environmental Change Scale, and Quality of Life Scale significantly improved in the test group. The quality of life for 14 items in the test group was significantly correlated. Daytime drowsiness, depression, and anxiety scale changes were significantly improved in the test group. According to the predictive survey, the subjects felt warmth in their body and comfort in mind during and after using loess bedding and evaluated that sleep quality was good. Conclusions: The overall quality of life in the test group increased using loess bedding.

Analysis of contribution and related factors of the elderly: Comparison between Korea and Canada (노인의 생산활동수준 및 관련변수의 분석: 한국과 캐나다 비교)

  • Joung, Soon Hee
    • 한국노년학
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    • v.25 no.2
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    • pp.155-170
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    • 2005
  • The purpose of study is to compare the level of participation of the elderly people in the activity of production between Korea and Canada and to identify the factors related to the participation of the elderly people in the activity of production between Korea and Canada. In order to conduct a comparative culture study two data sets were used; one was the 1999 Survey of Time Use collected by Korean Statistics Office and the other was 1998 Survey of Time Use collected by Canadian Statistics Office. Many countries have been collected a time use survey and used to study labor, welfare, and culture. Total number of 17,730 Korean and 2,729 Canadian between 55 and 84 were included to analyze the data. It is clear from the results that older people engage in various productive behaviors, particularly when the definition of activities is broadened to include unpaid work. It is also clear the overall productive contributions are higher among older Koreans than among older Canadians. While the focus in this study has been strictly on productive activities, the aging well literature suggests that the ability to remain independent in later life is enhanced through continued engagement in productive activities. It is thus critical that we better understand the nature of later-life activities and in particular the wide-ranging contributions made by older people. This is an important area of further exploration.

A study on the CRM strategy for medium and small industry of distribution (중소유통업체의 CRM 도입방안에 관한 연구)

  • Kim, Gi-Pyoung
    • Journal of Distribution Science
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    • v.8 no.3
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    • pp.37-47
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    • 2010
  • CRM refers to the operating activities that always maintain and promote good relationship with customers to ultimately maximize the company's profits by understanding the value of customers to meet their demands, establishing a strategy which may maximize the Life Time Value and successfully operating the business by integrating the customer management processes. In our country, many big businesses are introducing CRM initiatively to use it in marketing strategy however, most medium and small sized companies do not understand CRM clearly or they feel difficult to introduce it due to huge investment needed. This study is intended to present CRM promotion strategy and activities plan fit for the medium and small sized companies by analyzing the success factors of the leading companies those have already executed CRM by surveying the precedents to make the distributors out of the industries have close relation with consumers to overcome their weakness in scale and strengthen their competitiveness in such a rapidly changing and fiercely competing market. There are 5 stages to build CRM such as the recognition of the needs of CRM establishment, the establishment of CRM integrated database, the establishment of customer analysis and marketing strategy through data mining, the practical use of customer analysis through data mining and the implementation of response analysis and close loop process. Through the case study of leading companies, CRM is needed in types of businesses where the companies constantly contact their customers. To meet their needs, they assertively analyze their customer information. Through this, they develop their own CRM programs personalized for their customers to provide high quality service products. For customers helping them make profits, the VIP marketing strategy is conducted to keep the customers from breaking their relationships with the companies. Through continuous management, CRM should be executed. In other words, through customer segmentation, the profitability for the customers should be maximized. The maximization of the profitability for the customers is the key to CRM. These are the success factors of the CRM of the distributors in Korea. Firstly, the top management's will power for CS management is needed. Secondly, the culture across the company should be made to respect the customers. Thirdly, specialized customer management and CRM workers should be trained. Fourthly, CRM behaviors should be developed for the whole staff members. Fifthly, CRM should be carried out through systematic cooperation between related departments. To make use of the case study for CRM, the company should understand the customer and establish customer management programs to set the optimal CRM strategy and continuously pursue it according to a long-term plan. For this, according to collected information and customer data, customers should be segmented and the responsive customer system should be designed according to the differentiated strategy according to the class of the customers. In terms of the future CRM, integrated CRM is essential where the customer information gathers together in one place. As the degree of customers' expectation increases a lot, the effective way to meet the customers' expectation should be pursued. As the IT technology improved rapidly, RFID (Radio Frequency Identification) appears. On a real-time basis, information about products and customers is obtained massively in a very short time. A strategy for successful CRM promotion should be improving the organizations in charge of contacting customers, re-planning the customer management processes and establishing the integrated system with the marketing strategy to keep good relation with the customers according to a long-term plan and a proper method suitable to the market conditions and run a company-wide program. In addition, a CRM program should be continuously improved and complemented to meet the company's characteristics. Especially, a strategy for successful CRM for the medium and small sized distributors should be as follows. First, they should change their existing recognition in CRM and keep in-depth care for the customers. Second, they should benchmark the techniques of CRM from the leading companies and find out success points to use. Third, they should seek some methods best suited for their particular conditions by achieving the ideas combining their own strong points with marketing. Fourth, a CRM model should be developed that will promote relationship with individual customers just like the precedents of small sized businesses in Switzerland through small but noticeable events.

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