• 제목/요약/키워드: life-time use

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무선 애드혹 망에서의 전력 인식 동적 소스 라우팅 (Power-Aware Dynamic Source Routing in Wireless Ad-hoc Networks)

  • 정혜영;신광욱;임근휘;이승학;윤현수
    • 한국정보과학회논문지:정보통신
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    • 제31권5호
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    • pp.519-531
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    • 2004
  • 무선 애드혹 통신망은 고정된 기간망 없이 이동 기기들이 모여서 형성하는 임시 무선 시스템이다. 무선 애드혹 통신망에서는 이동 기기들이 모여서 통신망을 형성하므로 개개의 이동 기기의 수명이 통신망 자체의 수명을 결정짓는 중요한 요소가 된다. 망의 구조에 따라서 어떠한 경우는 단지 하나의 이동 기기가 자신의 배터리를 모두 소모하고 동작을 멈추었을 뿐인데, 이것이 통신망의 분할(partition)을 가져올 수도 있다. 이처럼 이동 기기의 수명은 각 이동 기기가 가지고 있는 배터리에 의존하므로 될 수 있는 한 소모하는 에너지량을 줄여 모든 이동 기기들이 골고루 오래 살수 있도록 하는 것이 전체 통신망의 수명을 늘릴 수 있는 방안이 된다. 본 연구에서는 모든 이동 기기들이 오랫동안 함께 살 수 있도록 최적의 경로를 선택하여 통신을 하도록 하는 전력 인식 동적 소스 라우팅(Power-Aware Dynamic Source Routing: PADSR) 프로토콜을 제안한다. PADSR에서는 송신 기기가 패킷(packet) 전송을 위한 경로를 선택할 때 어떤 특정 이동 기기의가 에너지를 많이 소모하지 않도록 하기 위하여 경로 선택 시에 경로에 포함되어 있는 이동 기기들의 남아있는 배터리량과 패킷을 전달하는데 소모하게 되는 송신 에너지량을 고려한다. 따라서 PADSR을 사용하게 되면 통신망의 수명이 연장된다.

Addition of Myofascial Release Therapy to Therapeutic Exercise for Management of Nonspecific Neck Pain

  • Ha, Yangsun;Hahm, Suk-Chan
    • 대한통합의학회지
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    • 제9권2호
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    • pp.35-41
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    • 2021
  • Purpose : It is necessary to demonstrate the effect of non-invasive and non-pharmacological interventions such as manual therapy and therapeutic exercise for the management of nonspecific neck pain. In the present study, we aimed to investigate the efficacy of myofascial release therapy plus therapeutic exercise for disability owing to neck pain and quality of life in individuals with nonspecific neck pain. Methods : Eighteen participants with nonspecific neck pain were randomly allocated to intervention (n=9) and control groups (n=9). The intervention group received a myofascial release therapy for 20 min and performed neck stabilization exercises for 30 min twice a week for 4 weeks. The control group performed neck stabilization exercises for 30 min twice a week for 4 weeks at the same time points as the intervention group. Disability owing to neck pain and quality of life were quantified using the neck disability index (NDI) and the Korean version of the World Health Organization Quality of Life Brief Version (WHOQOL-BREF), respectively. NDI and WHOQOL-BREF were assessed before and after intervention. Results : The disability owing to neck pain significantly changed between the groups over time (total score of NDI, p=.049). There were significant time and group interactions in pain (pain intensity of NDI, p=.035) and concentration (concentration of NDI, p=.049). Personal care, lifting, reading, headaches, work, driving, sleeping, and recreation did not show significant improvement between the groups over time. Total score, overall quality of life and general health, physical health domain, psychological domain, social relationships domain, and environmental domain quantified by WHOQOL-BREF did not show significant improvements between the groups over time. Conclusion : These results suggest the clinical use of myofascial release therapy in addition to therapeutic exercise for the management of nonspecific neck pain. Further studies are needed to generalize the findings of this study.

전북지역 영양교사의 식생활교육 실태와 연수 요구도 분석 (Operation and Training Demand on Dietary Life Education of Nutrition Teachers in Jeonbuk Province)

  • 박은숙
    • 한국생활과학회지
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    • 제23권1호
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    • pp.149-161
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    • 2014
  • The purpose of this study was to investigate the nutrition teachers' operation and demand of dietary life education in Jeonbuk Province. The study was carried out using a self administered questionnaire and the subjects were 190 nutrition teachers. The questions were general characteristics of the subjects, operating status as frequency, place, the main use time, and training demand on dietary life education by elementary school and middle & high school, teaching career, and training hours. The results are as follows. Most of the subjects were female(98.9%), more than half were 40's(52.1%) in their age, school work career was 13.2 years. Frequency of the dietary life education operation was once per month(56.8%), 2~3 times per month(27.9%), and place of education were dinning room (49.7%), classroom(25.9%). Almost of the subjects(90.4%) recognized the facilities for education was lack, 89.3% of them did the education materials was lack, also. The desirable frequency of dietary life education was once per month(48.9%), and once per week(35.3%.) The half of the subjects recognized the objects of the dietary life education was not only students but also their parents and teachers. The proper education time was dietary life education tim (34.2%), discretion activity time(31.1%). Most of the subjects(95.7%) had willing to get training, the proper training program was 30 hours, and they prefer summer vacation(61.0%) than winter vacation(30.5%) and semester(8.6%). Proper experimental practice ratio of environment : health : thanks were 30% : 43% : 27%. It is concluded that the demand of nutrition teachers is necessary for their education program in elementary and middle & high school.

파라미터를 이용한 LDPE 절연열화 과정의 수면예측 (A LIFE PREDICTION OF LDPE DEGRADATION PROCESSING USING PARAMETERS)

  • 김성홍;서장수
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2000년도 학술대회 논문집 전문대학교육위원
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    • pp.40-43
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    • 2000
  • Our studies diagnose insulation degradation using the method of computer sensing system, which has the advantages of PD(partial discharge) and AE(acoustic emission) sensing system. To use advantages of these two methods can be used effectively to search for treeing location and PD in some materials. In analysis method of degradation, using statically operator such as the center of gravity (G), the gradient of the discharge distribution(C), we have analyzed for the prediction of life which we can be obtained the time, occurred of many pulse of small discharge amplitude.

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보수 모르타르용 고성능 유동화제의 사용 적합성에 관한 실험적 연구 (A Study on the Experimental Study on Use Proper of Superplasticizer for Repair Mortar)

  • 김영삼;송태협;이문환;이세현
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2006년도 춘계 학술발표회 논문집(II)
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    • pp.297-300
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    • 2006
  • Recently, To extend building's life, the use amount of repair mortar has been rapidly increased and naphthalenesulfonic and melanminesulfonic, polycarboxylic superplasticizer etc. are used for repair mortar in large numbers of construction site for efficient work. In this study, it was going to examine the use proper of superplasticizer for repair mortar through the hydrate setting time test and flow test with the mortar combination which replaced by alumina cement and added superplasticizer. As a result, the fluidity of the mortar replaced by alumina cement(10%) and added superplasticizer was dropped down and setting time was shortened. Especially this appearance was more increased on the mortar combination added ploycarboxylic and melanminesulfonic superplasticizer than naphthalensulfunic superplasticizer.

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Evaluation of Performance and Service Life of Low Pressure LPG Regulators for Home Use

  • Kim Young-Gyu;Cho Seok-Beom;Kim Pil-Jong;Kwon Boo-Kil
    • Journal of Mechanical Science and Technology
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    • 제20권3호
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    • pp.329-334
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    • 2006
  • This paper presents the evaluation of LPG (Liquefied petroleum gas) regulators for home use. For the evaluation, several properties of the regulators were experimentally analyzed, such as the operation of safety device, the adjusting and lock-up pressure, the adjusting spring and the diaphragm, with respect to the used time of the regulators. Experimental results showed that the initial operation performances of regulators were degraded with increase of the service time and also showed that the degradation of the performance and material property could become serious after about six-year-use of the regulators.

장기사용된 1Cr-0.5Mo 주증기관의 수명평가 (Life Evaluation of Long-time Used 1Cr-0.5Mo Main Steam Pipe)

  • 백수곤;홍성인
    • Journal of Welding and Joining
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    • 제16권1호
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    • pp.70-76
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    • 1998
  • Most fossil power plants and many critical components will be approaching the end of their nominal design life. At the same time, utilities are finding it economically attractive to extend the use of these plants for several more years, Especially Main steam pipe that operated under high temperature and pressure, often under the more severe operating conditions associated with cycling duty, is most important pipe system and critical component in fossil power plant. To extend the viability of older pipe system and to improve the operation and maintenance reliability, some technologies of precise diagnosis and life management have evolved out of the necessity. The purpose of this study is to descrive the related technologies and show the example of one power plants. The purpose of this study is to descrive the related technologies and show the example of one power plants. The stress analysis was done using ANSYS FEM Code. The branch area from main steam to turbine was the high stressed zone. To evaluate the degradation of the pipe material, replica, visual check, magnetic test, hardness test were done at the welding spot. The degradation level of welding point was E/F, so the remaining life of the welded area was about 0-25%.

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Mixed Use Complex 디자인에 관한 연구 -업무/상업/문화오락/주거기능 복합의 사례분석을 중심으로- (A Study on the Mixed Use Complex Design)

  • 이혜진
    • 디자인학연구
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    • 제21권
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    • pp.207-217
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    • 1997
  • Mixed Use Area (Multifaceted Integration) is getting increasingly demanded since it has several merits such as preventing CBD from being emptied during night time, making daily life comfortable and utilizing the land more efficiently. However, the characteristic of Mixed Use Area -as advantages of it-, which is that it combines residence, retail, office, cultural, entertainment facilities altogether could be regarded as a weakness when it is viewed from each functions' original purposes such as residential and retail areas'. Accordingly, it is needed to do basic research and develop design guidelines of the Mixed Use Area to prepare its another take-off. The purpose of this research is to study theoretical background of Mixed Use Area's birth, understand its status quo by examining examples overseas and presented possible standardized ways of developing it.

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은퇴한 노인의 생활시간 사용에 관한 연구 (A Study on the Time Usage of the Retired Elderly)

  • 이신숙
    • 한국생활과학회지
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    • 제20권2호
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    • pp.311-325
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    • 2011
  • The purpose of this study was to analyze patterns of time usage of the retired elderly so as to improve their quality of life. The subjects of this study were 225 elderly people in Jeonnam Province. The statistics used for data analysis were frequency, percentage, mean, standard deviation, t-test, and multiple regression. The major findings were as follows : (1) The retired elderly spend more time in physiological activities and leisure, and there was no day difference in time use. (2) On weekdays, the variables affecting labor time were age, former job, health state, and education. On the weekends, education, health state, and former job had significant effects on the amount of time spent on labor. (3) The variables affecting participation and volunteer time were: monthly living expenses, age, spouse, former job, and house, on weekdays, and on the weekends, significant factors were spouse, age, and former job. (4) The variables affecting leisure time were education, age, monthly living expenses, religion, and economic state, on the weekdays, and on weekends, the significant factors were education, economic state, house, religion, and former job.

서울시 통행시간 변화의 요인분석: 생활시간조사자료를 중심으로 (Analysis of Factors Affecting Travel Time Change Using the Time Use Survey Data in Seoul)

  • 구자헌;추상호
    • 한국ITS학회 논문지
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    • 제17권1호
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    • pp.1-16
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    • 2018
  • 생활패턴의 변화는 통행의 목적을 변화시키기 때문에 궁극적으로 통행패턴의 변화를 야기한다. 이에 따라 본 연구에서는 1999년부터 2014년까지 통계청에서 조사한 생활시간조사자료를 활용하여 연도별 통행시간에 영향을 미치는 요인을 분석하고자 한다. 가구관련, 개인관련, 시간관련 변수들을 고려한 통행시간에 관한 다중선형회귀모형을 구축하였으며, 요일별 차이를 보기위해 주중과 주말을 분리하여 추정하였다. 모형 추정 결과, 가구관련, 개인관련, 시간관련 변수가 통행시간에 영향을 미치는 것으로 분석되었다. 가구관련변수의 경우 개인관련변수에 비해 비교적 적은 변수들이 유의한 것으로 나타났는데, 이는 통행이 개인특성에 더 큰 영향을 받기 때문인 것으로 판단된다. 각 활동시간들은 통행시간에 양의 영향을 미치는 것으로 분석되어 통행이 파생수요임을 나타내고 있다. 또한 여가활동시간이 가장 큰 영향력이 있는 것으로 도출되어, 여가를 위한 통행시간이 타활동에 비해 증가하는 것으로 분석되었다.