• 제목/요약/키워드: 30years

검색결과 9,228건 처리시간 0.036초

기후변화에 따른 R-Factor 값을 고려한 토양 유실량 평가 (The Evaluation of Soil Loss Considering the R-Factor Value Following the Climate Change)

  • 박재현;김동주;김민규;장춘화;강현우;금동혁;임경재
    • 한국관개배수논문집
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    • 제21권1호
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    • pp.64-77
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    • 2014
  • This study evaluated the soil loss considering the R-Factor value following the climate change. To calculate the soil loss of the basin in Jaun-ri, Hongcheon-gun which is the study area, the future climate change scenario and convenience revision were used to build the past 30 years, future 30 years R-Factor and it was applied to USLE model. As a result, as the R-Factor value declined a little in the future, the soil loss was also reduced but it corresponds to the 'very high' according to the OECD soil loss grade so the solution to reduce the soil loss is necessary and it can be used for another study material.

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후천성 심질환의 인공판막치환술에 대한 임상적 고찰 (Clinical Analysis of Prosthetic Valve Replacement on Acquired Heart Disease)

  • 이준영;지행옥
    • Journal of Chest Surgery
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    • 제22권6호
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    • pp.951-959
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    • 1989
  • Between September, 1972 and September, 1989, total 359 patients were operated for acquired heart disease at Department of Thoracic and Cardiovascular Surgery, Hanyang University Hospital. A consecutive series of 293 prosthetic valve replacement was also performed during this period. The results were summarized as follows; 1. There were 141 men and 218 women, whose ages ranged from 6 to 64 years, [mean 35.5 years] 2. Out of 293 cases, mitral valve replacement was 182 cases, aortic valve replacement was 39 cases and double valve replacement was70 cases. 3. Early post-operative death was 30 cases [Mortality; 8.4 %] and late death was 9 cases in the survivors. 4. Re-operation was 30 cases and operative mortality was 10%. 5. Mean post-operative interval was 76 months. [Ranged from 216 months to 2 months] 6. Among re-operation cases, primary prosthetic valve failure was 16 cases and paravalvular leakage was 2 cases. 7. Since January 1988, 79 cases of prosthetic valve replacement were performed and then 1 case was expired. [Mortality; 1.2 %]

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Load-Carrying Capacity Assessment of Deteriorated Rural Bridge

  • Kim, Han-Joong;Kim, Jong-Ok;Yang, Seung-Ie
    • 한국농공학회지
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    • 제44권7호
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    • pp.36-45
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    • 2002
  • Most of rural bridges have passed 30 years of age since they were built, which have to support unexpected overload caused by changed design load and excessive amount of transportation. For these rural bridges, repairs and replacements are needed. Even though there have been attempt to estimate the safety of existing bridges deteriorated with major defects, those approaches must rely on the observable damage and subsequent decisions are made subjectively. To avoid the high cost of rehabilitation, the bridge rating must correctly represent the present load-carrying capacity. Rating engineers use a methods such as Allowable Stress Design (ASD), Load Factor Design (LFD), and Load Resistance Factor Design (LRFD) to evaluate the bridge load carrying capacity. In this paper, the load rating methods are introduced, and it is illustrated how to use the load test data from literature survey. Load test is conducted to the bridge that was built 30 years ago in rural area. From load test results, new maintenance method is suggested instead of the bridge replacement.

Sex Ratio and Approximate Date of Fertilization of the Subsocial Spider Amaurobius ferox Walckenaer (Araneae: Amaurobiidae)

  • Kim, Kil-Won;Choe, Jae-Chun
    • Journal of Ecology and Environment
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    • 제30권3호
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    • pp.277-280
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    • 2007
  • Social spiders consistently show highly female-biased sex ratios. However, the sex ratio of subsocial spiders, which have been suggested as an intermediate stage of the evolutionary pathway towards permanent sociality, is generally unknown. We investigated the sex ratio and approximate date of fertilization of the subsocial spider, Amaurobius ferox Walckenaer (Araneae: Amaurobiidae). Investigation over 2 years revealed that sex ratio of A. ferox was consistent across years and averaged 0.49. By early May $(1^{st}{\sim}10^{th})$, 66.6% of female A. ferox observed in the field had already been inseminated, and by late May $(21^{st}{\sim}31^{th})$, 95.4% of females had been inseminated. This result suggests that A. ferox need a long time or cold temperatures to prepare them for reproduction after the developmental attainment of the adult stage.

Biodiversity and Distribution of Arbuscular Mycorrhizal Fungi in Korea

  • Eo, Ju-Kyeong;Park, Sang-Hee;Lee, Eun-Hwa;Eom, Ahn-Heum
    • 한국균학회지
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    • 제42권4호
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    • pp.255-261
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    • 2014
  • In this study, we summarized previous studies on diversity and distribution of arbuscular mycorrhizal fungi (AMF) for last 30 years in Korea. According to a review of the literature concerning AMF in Korea, 14 genera and 89 species have been recorded. Host plants for AMF are very diverse and include crop species and woody plants in natural forests. Based on the achievements of the last 30 years of study on AMF, we anticipate that relatively more intensive studies of the functional and genetic diversity of AMF will be conducted.

한의대생의 MBTI 성격유형의 변화에 대한 연구 (A Study on the MBTI Personality Type Change of the Korean Medical Students)

  • 이재혁
    • 동의신경정신과학회지
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    • 제30권2호
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    • pp.39-45
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    • 2019
  • Objectives: To study the change of personality types of Korean medical students focusing on the Myers-Briggs Type Indicator. Methods: A survey was conducted on 84 Korean medical students to investigate the change of personality types focusing on the Myers-Briggs Type Indicator. Results: In both freshman and senior student groups, the ISTJ was the most common type. The order of the number of the type changes during the university years was 1 type (45.2%)>2 types (23.8%)>3 types (14.3%)>0 types (11.9%)>4 types (1.8%), and the score of I, S, T, P type increased. Conclusions: As a result of the Korean medical students' MBTI type changes during the university years, the types were changed rather than fixed.

인공 조직 판막의 임상 성적 (Clinical Analysis of Bioprosthetic Heart Valves)

  • 김택진
    • Journal of Chest Surgery
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    • 제24권11호
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    • pp.1074-1080
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    • 1991
  • A total and consecutive 62 patients between 13 and 58 years of age receiving biological prosthetic heart valves at the Korea University Hospital from January 1978 through October 1983 were analyzed. Out of 71 valves replaced, 64 were Carpentier-Edwards valves, 4 were Ionescu-Shiley valves, 2 were Angell-Shiley valves, 1 was Hancock valve. Early mortality within 30 days after operation was noted in 4 cases[6.4%]. There were no cases of valve-related early death. The 58 early survivors were followed-up for a total 387 patient-year over a period of 3 years to 12 years[Mean$\pm$S.D: 6.37$\pm$2.51 years] at the follow-up end of April 1991. During follow-up, seven patients died and late mortality rate was 12%. There were two major late complications: the one is thromboembolism[1.6% /patient-year], the other is primary tissue failure[2.76% /patient-year]. Ten patients underwent re-replacement of 13 tissue valves because of primary tissue failure[nine Carpentier-Edwards, two Ionescu-Shiley, two Angell-Shiley]. There was operative mortality. The probabilities of freedom from primary tissue failure were 95.4% and 75.3% at 5 and 10 years after operation respectively, The actuarial survival rates were 86.2% and 81.8% at 5 and 10 years after initial surgery respectively.

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성인에서의 서천성 심장기형의 외과적 치료 (Surgical Teatment of Congenital Cardiac Malformations in the Adult -A Report of 1389 Surical Cases-)

  • Kyu
    • Journal of Chest Surgery
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    • 제28권8호
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    • pp.747-753
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    • 1995
  • Patients over 14 years of age who have undergone a surgical correction of a congenital cardiac malformations during period of August 1959 through December 1993 have been reviewed. During this period, there were 6894 cases of congenital cardiac lesions consisting of 4576 acyanotic and 2318 cyanotic cases. Among them, a total of 1389 adults [20.1%with various congenital cardiac malformations, 1126 acyanotic group and 263 cyanotic group were operated on. 677 patients were male and 712 patients were female. There were 444 patients under 20 years of age, 365 patients between 20-24 years, 220 patients between 25-29 years, 138 patients between 30-34 years and 222 patients over 34 years. The most common defects were atrial septal defect which accounted for 500 cases [36.0%and another common malformations were ventricular septal defect [276 cases, 19.9% , patent ductus arteriosus [207 cases, 14.9% , tetralogy of Fallot [185 cases, 13.3%and pulmonary stenosis [44 cases, 3.2%in order of incidence. Overall operative mortality for this series was 2.7% [1.5% of acyanotic group and 7.9% of cyanotic groupcompared with 4.6% of operative mortality of total cases of congenital cardiac malformations [2.9% of acyanotic group and 16.7% of cyanotic group . This reviewed series reveals the incidence of operable congenital heart defects appearing in any adult life and demonstrates that surgical repair can be accomplished with a satisfactory low mortality rate.

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사마귀 클리닉 내원환자에 대한 통계적 고찰 (A Statistical Study of Patients visited Wart Clinic)

  • 윤정민;신상호;윤화정;고우신
    • 한방안이비인후피부과학회지
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    • 제22권2호
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    • pp.192-200
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    • 2009
  • Objective : The purpose of this study is to investigate the characteristics of patients with warts. Methods : We conducted statistics study on 100 patients, who had visited to Wart Clinic, from September 2008 to February 2009. Results : The results were as follows. 1. The wart was found more often from female(64%) than from male(36%). The age distributions of patients showed highest in 21-30 years, followed by 31-40 years, and 11-20 years. 2. The distributions of duration of warts showed highest in 1-5 years, followed by 6-10 years, and over 10 years. 3. The most common warts were Verruca plana(48%), Verruca vulgaris(25%), Verruca vulgaris with Palmoplantar wart(14%), Verruca plana with Verruca vulgaris(9%). 4. The Verruca vulgaris was found mostly in the hand, whereas the Verruca plana was seen mostly in the face. 5. Laser therapy was the most common previous treatment, followed by cryotherapy, immunotherapy in order. 6. The distributions of duration of treatment showed highest in 1-4 weeks, followed by 5-8 weeks, 9-12 weeks in order. 7. After treatment, 43 cases(43%) showed complete clearance, and 29 cases(29%) showed partial clearnace. Conclusion : We analyzed the characteristics of patients with warts. Further studies would be needed to develop the better treatment on warts.

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누전차단기 실태조사 및 교체주기에 관한 연구 (A Study on the Real Condition and Life Time of the RCD)

  • 김종민;최명일;김영석;방선배;송길목;서정열
    • 전기학회논문지P
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    • 제59권4호
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    • pp.467-472
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    • 2010
  • In this study, an analysis of the used RCD's condition is conducted to assess the effect on environment of installation area, terms of use, corrosion, contamination etc. According to KS C 4613, the used RCDs were tested to get date which is the RCD's life time. And then, the date is analysed using Minitab which is a statistical program for reliability analysis. As a result, The RCD's MTTF for the all samples is $12.7{\pm}0.23$ years. and the MTTF of RCDs which are used indoor area is $12.9{\pm}0.34$ years, the MTTF of RCDs which are used outdoor area is $11.9{\pm}0.30$ years. Futhermore, the MTTF of RCDs which are used in dry area is a $13.1{\pm}0.26$ years, the MTTF of RCDs which are used in dust area is $13.0{\pm}0.57$ years, the MTTF of RCDs which are used in moisture area is $8.4{\pm}0.77$ years.