• 제목/요약/키워드: Mean residual life function

검색결과 36건 처리시간 0.02초

이중 링크 형식 수평 인입 집 크레인의 피로 해석, 신뢰도 및 수명 예측에 관한 연구 (A Study on Fatigue Analysis, Reliability and Life Expectancy of a Double Link Type Level Luffing Jib Crane)

  • 허철원;문덕홍
    • 한국안전학회지
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    • 제16권4호
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    • pp.65-73
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    • 2001
  • This paper is a study on the fatigue analysis using BS5400 Part10(1980), code of practice for fatigue for a double link type level luffing jib crane which has been operated since the crane was built in 1985 at a domestic pier. South Korea. In addition, on the basis of the design lift due to fatigue analysis and the number of cracks detected from the nondestructive test the structural reliability and the residual life of the crane is predicted by evaluating the expected development of detectable fatigue oracle during the next five to ten years using Paris's Law for predicting fatigue crack growth and Gaussian probability density function to be reasonable for stress ranges below the mean values determined by laboratory tests. The statistical data used for the analysis of the structural reliability and life expectancy is given in the above referred code.

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뇌성마비 성인의 근골격계와 기능 실태 (Musculoskeletal and Functional Status of Adults with Cerebral Palsy)

  • Yoon Myung-ok;Kim Chung-sun
    • The Journal of Korean Physical Therapy
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    • 제17권1호
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    • pp.43-68
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    • 2005
  • The purpose of this study was to report the physical status of adult with cerebral palsy who live in local community areas including Seoul, Busan, Daegu in Republic of Korea at 2004. 202-individuals with cerebral palsy(140 male, 62 female; mean age 31.9 years; range 19 to 64 years) were surveyed. Measures included a 29-item self-reported health status measure focusing on musculoskeletal status and functional performances. Adult cerebral palsy required continuous management for musculoskeletal and ambulatory function through therapeutic approach. This survey is restricted to population who had cared in welfare center for cerebral palsy in local community, so it needs to investigate home-residual adults with cerebral palsy and the population in rural community. The results were as follows: 1. Participants reported that they had a limitation of a daily of life activity due to musculoskeletal pain($43\%$), there was significant differences between a limitation of a daily of life activity and the decreased ambulatory function(p<.05). 2. Thirty six point six percentile of participants had the decreased ADL function, it was significant related with the impaired body location(p<.05) 3. Thirty nine point one percentile of participants who can independently gait had the decreased ambulatory function, it was significant differences with the usage of ambulatory assistive devices(p<.05). 4. There was significant differences ambulatory function both the body region with impairment and a grade of disability(p<.05). 5. Sixteen point three percentile of participants could not ambulate any more, there was significant differences between a age and a point of time for non-ambulation(p<.05). 6. There was significant differences between ambulatory function and physical activity(p<.05).

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의치 장착 노인과 임플란트 장착 노인의 저작능력 및 삶의 질 비교 연구 (A study of comparative the mastication capability and life quality of elderly people using dentures or implants)

  • 김영숙;전보혜
    • 한국치위생학회지
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    • 제11권5호
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    • pp.629-636
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    • 2011
  • Objectives : The purpose of this study was to determine the effects of oral health on the quality of life of elderly patients with dentures or implants. It is our intention that through this analysis we can aid seniors in making the choice between dentures or implants, considering future masticatory function and the likely effects of this decision on the patients quality of life. Methods : This survey was conducted between November 1, 2010 and November 25, 2010, in Kyunggi-Do, whasung city. The research was carried out at one public health center, among elderly patients. 105 seniors were surveyed using the direct interviewing method, oral health related quality of life was measured by the Philadelphia Geriatric Center(PGC) Morale Scale. Collected data was examined using the SPSS 13.0 program, using frequency, mean, and standard deviation analysis, T-test and $x^2$ test. Results : The number of residual teeth for patients who have implants was $20.45{\pm}5.85$, while among those patients with dentures the number was considerably lower, $8.11{\pm}7.66$(p<0.05). The results of patients masticatory function, was $28.13{\pm}2.40$ for those with implants, and $25.35{\pm}4.15$ with dentures. The results were better for those with implants. Among implant patients overall satisfaction was rated $25.21{\pm}3.63$, higher than for those with dentures $20.20{\pm}6.79$(p<0.05). Quality of life was scored higher for patients with implants($12.76{\pm}2.61$) compared to those with dentures($10.47{\pm}3.52$)(p<0.05). The subjects masticatory function was highly related to the number of remaining teeth and greater masticatory function had a positive effect on patients quality of life and life satisfaction. Conclusion : Dental treatments such as dentures and implants will have a great influence on patients quality of life and life satisfaction. Implants can improve the oral health related quality of life and satisfaction and the general quality of life more than denture therapy.

A software reliability model with a Burr Type III fault detection rate function

  • Song, Kwang Yoon;Chang, In Hong;Choi, Min Su
    • International Journal of Reliability and Applications
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    • 제17권2호
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    • pp.149-158
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    • 2016
  • We are enjoying a very comfortable life thanks to modern civilization, however, comfort is not guaranteed to us. Development of software system is a difficult and complex process. Therefore, the main focus of software development is on improving the reliability and stability of a software system. We have become aware of the importance of developing software reliability models and have begun to develop software reliability models. NHPP software reliability models have been developed through the fault intensity rate function and the mean value functions within a controlled testing environment to estimate reliability metrics such as the number of residual faults, failure rate, and reliability of the software. In this paper, we present a new NHPP software reliability model with Burr Type III fault detection rate, and present the goodness-of-fit of the fault detection rate software reliability model and other NHPP models based on two datasets of software testing data. The results show that the proposed model fits significantly better than other NHPP software reliability models.

Optimal Monitoring Frequency Estimation Using Confidence Intervals for the Temporal Model of a Zooplankton Species Number Based on Operational Taxonomic Units at the Tongyoung Marine Science Station

  • Cho, Hong-Yeon;Kim, Sung;Lee, Youn-Ho;Jung, Gila;Kim, Choong-Gon;Jeong, Dageum;Lee, Yucheol;Kang, Mee-Hye;Kim, Hana;Choi, Hae-Young;Oh, Jina;Myong, Jung-Goo;Choi, Hee-Jung
    • Ocean and Polar Research
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    • 제39권1호
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    • pp.13-21
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    • 2017
  • Temporal changes in the number of zooplankton species are important information for understanding basic characteristics and species diversity in marine ecosystems. The aim of the present study was to estimate the optimal monitoring frequency (OMF) to guarantee and predict the minimum number of species occurrences for studies concerning marine ecosystems. The OMF is estimated using the temporal number of zooplankton species through bi-weekly monitoring of zooplankton species data according to operational taxonomic units in the Tongyoung coastal sea. The optimal model comprises two terms, a constant (optimal mean) and a cosine function with a one-year period. The confidence interval (CI) range of the model with monitoring frequency was estimated using a bootstrap method. The CI range was used as a reference to estimate the optimal monitoring frequency. In general, the minimum monitoring frequency (numbers per year) directly depends on the target (acceptable) estimation error. When the acceptable error (range of the CI) increases, the monitoring frequency decreases because the large acceptable error signals a rough estimation. If the acceptable error (unit: number value) of the number of the zooplankton species is set to 3, the minimum monitoring frequency (times per year) is 24. The residual distribution of the model followed a normal distribution. This model can be applied for the estimation of the minimal monitoring frequency that satisfies the target error bounds, as this model provides an estimation of the error of the zooplankton species numbers with monitoring frequencies.

지속성 기흉에서 자가혈액을 이용한 흉막유착술의 효과 (The Effects of Autologous Blood Pleurodesis in the Pneumothorax with Persistent Air Leak)

  • 윤수미;신성준;김영찬;손장원;양석철;윤호주;신동호;정원상;박성수
    • Tuberculosis and Respiratory Diseases
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    • 제49권6호
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    • pp.724-732
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    • 2000
  • 연구배경 : 심한 폐기능 장애가 만생 폐질환 환자에서 발생한 기흉은 그 정도가 심하지 않더라도 심한 호흡곤란을 일으켜 환자의 생명을 위협하기도 한다. 우선 공기 천자 및 흉관삽입을 시행한 후에도 공기누출이 지속되는 경우 흉강경을 이용한 수술적 치료로 공가누출을 근원적으로 막는 것이 가장 좋은 방법이다. 그러나 심한 폐 손상으로 흉강경 삽입을 할 수 없는 경우에는 삽입된 흉관을 통하여 흉막유착을 시도하게 된다. 흔히 사용되는 제재는 tetracycline, talc powder, silver nitrate 등이며 때로는 OK-432, 항암제인 bleomycin, mitomycin등이 사용되기도 한다. 한가지 방법으로는 실패한 경우 다른 약제로 재시도 하지만 그래도 공기누출이 지속되는 경우에는 입원기간이 장기화 되면서 경제적 손실이 따르고 호흡기 합병증이 발생가능하며 때로는 사망할 수도 있다. 또한 주로 사용되던 주사용 tetracycline과 doxycycline 마저 최근 국내 생산이 중단되어 새로운 흉막유착물로의 대체가 필요한 실정이다. 한편 외상등으로 발생한 혈흉에서 적절히 배액되지 않으면 섬유흉(fibrothorax)이 발생 하며, 심한 경우 외과적 흉막박피술로 이를 제거하여야 할 정도로 혈관 밖으로 나온 혈액은 흉강내에서는 강력한 자극제로서 조직간에 유착을 일으킨다는 사실이 이미 알려져 있어 이를 이용한 자가혈액 흉막유착술의 유용성을 알아보고자 하였다. 방법 : 공기누출이 지속되는 기흉이 합병된 중증 만성 폐질환 환자에서 자가혈액 흉막유착을 시행하였다. 이들은 수술적 치료에 적응증이 되지 않았고 일차적으로 시행한 doxycycline 흉막유착술에 실패한 예이다. 흉관 삽입 후 폐가 충분히 펴진 다음에 정맥에서 채취한 환자의 혈액과 50% dextrose를 같은 비율로 섞은 용액을 흉관 또는 pig-tail 카테터를 통하여 흉강대로 주입하여 흉막유착술을 수회 시행하였다. 이의 효과와 통증의 정도, 합병증 여부를 확인하였고, 기흉 발생 이전과 흉막유착후의 호흡곤란 정도와 폐기능의 변화에 대하여 조사하였다. 결과 : 자가혈액 흉막유착술은 지속적인 공기누출이 있는 기흉을 가진 대부분의 대상환자에서 성공적이었으며 1예에서만 6개월 뒤 재발하였다. 자가혈액 흉막유착술 이전의 공기누출기간은 평균 18.4일 이었고 이후는 5.2일 이었다. 일차로 시행한 doxycycline 흉막유착술에 비하여 통증이 적었으며 시술중 4예에서 미열이 있었고 이외의 다른 합병증은 없었다. 평균 21개월(2~68개월)간 추적검사 하였는데 흉막유착은 8예에서 경도로 있었다. 기흉발생 이전과 흉막유착술 시행 후의 호흡곤란 정도와 폐기능 변화는 없었다. 결론 : 자가혈액은 흉막유착술에 이용될 수 있는 유용한 제재로 생각된다. 지속척인 공기유출이 있는 기흉에서 쉽고 적은 비용으로 효과적으로 사용될 수 있었고 시술중이나 시술후에 큰 합병증도 발견되지 않았으며 무엇 보다도 혈액은 얻기가 쉽다. 기존의 doxycycline을 이용한 흉막유착술에 비하여 환자가 통증을 적게 호소하여 편안할 뿐만 아니라 tetracycline계의 약물과 달리 혈액은 때로는 patch로 작용하여 공기누출을 막는 효과가 더 높으며 추적 관찰 결과 시술후의 늑막유착은 심하지 않았다. 따라서 중증 만성 폐질환 환자에서 지속적인 공기누출이 있는 기흉이 있고 수술적 치료에 의한 적용이 되지 않는 경우 자가혈액을 이용한 흉막유착술은 유용한 치료법이라고 사료된다.

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