• 제목/요약/키워드: Reduction effect of settlement

검색결과 77건 처리시간 0.021초

단계석션압 조건에 따른 석션보드드레인 공법의 효율 분석 (Analysis of Efficiency of Suction Board Drain Method by Step Vacuum Pressure)

  • 김기년;한상재;김수삼
    • 대한토목학회논문집
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    • 제28권6C호
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    • pp.321-329
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    • 2008
  • 본 연구에서는 전통적인 압밀촉진공법의 단점을 보완하기 위한 방법으로 석션보드드레인 공법을 제안하고, 본 공법의 개량특성을 파악하기 위해, 배수재 종류 및 단계 진공압 조건에 따른 일련의 Column 실험을 실시하였다. 이때 실험 간 발생되는 침하량과 실험 종료 후 발생된 함수비 저감효과 및 강도증진효과를 파악하고, 개량 기간에 따른 압밀도를 파악하여 각 조건에 따른 최적의 석션보드드레인 공법 영향인자를 산정하고자 하였다. 각 배수재(포켓식 성곽형, 코일형, 하모니카 형, 원형 및 열융착식 성곽형배수재) 종류에 따른 개량 효과를 파악하기 위한 실험 결과, Core 형상(원형, 판형)과 필터의 Core 부착 여부(포켓식, 열융착식)에 의해 열융착식 성곽형 배수재와 포켓식 원형배수재의 배수효율이 다른 배수재의 경우 보다 좋게 나타났다. 단계석션압 조건 실험의 경우 최종 단계석션압인 $-0.8\;kg/cm^2$으로의 기간이 짧을수록 개량도가 크게 나타났다. 또한 각 석션압 단계 별 압밀도-적용기간 곡선 상의 변곡점을 이용하여 압밀효과를 극대화 시킬 수 있는 적용기간을 산정할 수 있었다.

웹기반 굴착 영향도 예측 및 위험도 평가 시스템 개발 (Development of web-based system for ground excavation impact prediction and risk assessment)

  • 박재훈;이호;김창용;박치면;김지은
    • 한국터널지하공간학회 논문집
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    • 제23권6호
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    • pp.559-575
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    • 2021
  • 최근지반굴착 공사의 증가로 인해 지반침하사고 발생 가능성은 점점 높아지고 있지만, 지하안전관리에 관한 특별법 제정 등 제도적인 강화에도 불구하고 지반침하사고를 근본적으로 예방하는 것은 매우 어려운 실정이다. 도심지 지반굴착의 여러 사례를 살펴보면, 굴착 전에 다양한 정보를 활용해 예측했던 지반침하 거동특성은 시공 중에 확인된 결과와 무시할 수 없을 정도의 차이를 보이고 있다. 이러한 원인은 지반조건의 변화, 지반침하 예측방법의 한계, 설계와 착공 시기의 계절적인 차이, 현장여건을 고려한 공법의 변경 및 기타 다양한 사유에 의한 장기간의 공사 중지 등의 현장 여건 변경이 주요 원인으로 고려될 수 있다. 이에 대응하기 위한 방안으로, 다양한 시공정보를 통한 안전관리시스템 도입을 예를 들 수 있으나 아직까지는 굴착으로 인한 영향 및 위험도를 예측할 수 있는 시스템은 부재한 실정이다. 본 연구에서는 도심지 굴착사업의 설계·시공에 있어서 지반침하와 주변 구조물에 미치는 굴착 영향도를 사전에 예측하고 위험도 평가를 할 수 있는 시스템을 개발하였으며, 과거에 획득된 현장계측 데이터를 통해 현재 및 장래 지하수위와 침하량 등을 예측할 수 있는 시계열 분석기법과 지반공학 데이터 시각화(Geotechnical Data Visualization, GDV) 기술을 적용하였다. 본 연구에서 개발된 웹기반 평가시스템을 통해 과거에 획득된 데이터를 이용하여 현재 및 장래 지하수위 변화 및 침하량 예측 등 굴착으로 인한 위험도 예측 및 관리가 가능할 것으로 기대된다.

중소벤처기업의 SCM역량과 프로세스 개선이 운영성과에 미치는 영향 (The Effects of SCM Competency and Process Improvement on Operational Performance in Small and Venture Companies)

  • 이설빈;박주경
    • 벤처창업연구
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    • 제13권6호
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    • pp.143-154
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    • 2018
  • 본 연구는 중소벤처기업의 SCM(공급사슬관리)역량과 프로세스 개선이 운영성과에 미치는 영향력을 밝히는데 목적을 갖고 중소벤처제조기업 179개사를 대상으로 실증 분석하였다. 연구결과를 보면 중소벤처기업의 SCM역량이 프로세스 개선과 운영성과에 유의한 영향을 미쳐 가설은 모두 채택되었다. 또한, 중소벤처기업의 SCM역량이 운영성과에 미치는 영향에서 프로세스개선의 매개효과 또한 유의적인 영향을 미쳐 가설4도 채택되었다. 이와 같은 결과는 중소벤처기업의 SCM역량으로서의 전략적 제휴, 기술개발, 역량집중화 요인과 프로세스 개선 요인으로서의 착수 준비, 상세 계획, 실행 관리 요인이 운영성과 요인으로서의 품질성과, 원가절감, 수익증가에 긍정적인 영향을 미치는 요인임을 실증해 주었다. 이는 중소벤처기업에서의 SCM을 도입하여 역량을 극대화시켜 프로세스를 보다 개선시키고 성과를 높이기 위해 중소벤처기업에 적합한 전략적 제휴와 기술 개발과 동시 역량집중화를 위한 선별적 투입전략이 요구됨을 의미한다. 따라서 이의 조기 적용과 정착을 위해 중소벤처기업 자체 내 업무 프로세스의 착수준비, 상세계획을 기획하여 뚜렷한 전사적 목표 관리하에 공동 실행에 옮김으로서 이들 속성에 비례한 엄격한 관리와 실행이 이어질 때 기대성과 또한 극대화 될 수 있음을 시사해준 것으로 평가할 수 있다.

Reliability of mortar filling layer void length in in-service ballastless track-bridge system of HSR

  • Binbin He;Sheng Wen;Yulin Feng;Lizhong Jiang;Wangbao Zhou
    • Steel and Composite Structures
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    • 제47권1호
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    • pp.91-102
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    • 2023
  • To study the evaluation standard and control limit of mortar filling layer void length, in this paper, the train sub-model was developed by MATLAB and the track-bridge sub-model considering the mortar filling layer void was established by ANSYS. The two sub-models were assembled into a train-track-bridge coupling dynamic model through the wheel-rail contact relationship, and the validity was corroborated by the coupling dynamic model with the literature model. Considering the randomness of fastening stiffness, mortar elastic modulus, length of mortar filling layer void, and pier settlement, the test points were designed by the Box-Behnken method based on Design-Expert software. The coupled dynamic model was calculated, and the support vector regression (SVR) nonlinear mapping model of the wheel-rail system was established. The learning, prediction, and verification were carried out. Finally, the reliable probability of the amplification coefficient distribution of the response index of the train and structure in different ranges was obtained based on the SVR nonlinear mapping model and Latin hypercube sampling method. The limit of the length of the mortar filling layer void was, thus, obtained. The results show that the SVR nonlinear mapping model developed in this paper has a high fitting accuracy of 0.993, and the computational efficiency is significantly improved by 99.86%. It can be used to calculate the dynamic response of the wheel-rail system. The length of the mortar filling layer void significantly affects the wheel-rail vertical force, wheel weight load reduction ratio, rail vertical displacement, and track plate vertical displacement. The dynamic response of the track structure has a more significant effect on the limit value of the length of the mortar filling layer void than the dynamic response of the vehicle, and the rail vertical displacement is the most obvious. At 250 km/h - 350 km/h train running speed, the limit values of grade I, II, and III of the lengths of the mortar filling layer void are 3.932 m, 4.337 m, and 4.766 m, respectively. The results can provide some reference for the long-term service performance reliability of the ballastless track-bridge system of HRS.

사업장 보건관리 사업의 형태별 수행성과 분석 -비용편익 분석을 중심으로- (Performance of Occupational Health Services by Type of Service : Cost Benefit Analysis)

  • 조동란;김화중
    • 한국직업건강간호학회지
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    • 제4권호
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    • pp.5-29
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    • 1995
  • Occupational health services in Korea have been operated as dual types : one is operated by occupational health care manager and the other is health care agency without their own personnel. The performance of occupational health service should be different due to the variety of characteristics of health care manager and workplace, qualification of health care manager. This study is to analyze performance of occupational health care services with a particular consideration of job performance shape and efficiency, based on comparing those two types of health care management to show on the basic data for the settlement of more qualitative health care management system at workplace. For this study, total 391 places in Seoul and Inchon city area ; 154 places (39.4%) managed by designated health care manager and 237 places (60.6%) by the agency with their commission are selected as research samples. Tools for data collection are questionnares that have been investigated during the period of 20 September 1993-20 December 1993. Those data are compared with percentiles, mean, standard deviation and B/C ratio using SPSS PC program. Conclusions observed from the tests and each comparison could be summerized as follows : 1. Occupational health care have been accomplished at workplaces with designated people than with agencies people, and coverage rate of the occupational health care services has differences, due to management types. The reason of these results is due to visit only one or two times monthly by the agencies, while their own health care manager obsess, at the workplaces all the times. 2. Most of the expense for environmental control of all health care services expenditures shows that there is almost no fundamental improvement because more expenses are needed for procuring personal protective equipment and measuring work environment instead of environmental improvement. 3. It is investigated how much the cost of occupational health care services needs per worker, and calculated how much the cost needs per service hour per worker. The results from this show that the cost of occupational health services at workplaces with their own managers used less than the cost of health care agencies, eventually the former gives better services with less cost than the latter. 4. Benefit/Cost ratio is also produced by total benefit/total cost. The result from the above way reads 4.57 as a whole, while their own manager having workplaces reads 4.82 and the agencies do l.56. Even if their own manager performing workplaces spent more cost, this system produces more benefit than the agencies management. 5. The B/C ratio for medical organization such as local clinic, health care center and pharmacy shows more than or equal to at the workplaces controlled by the agencies. It is inferred that benefit would be much less than the cost used, with so being inefficient. 6. It is assumed that the efficiency ratio of health education is equal to reduction rate of workers medical organization visit. Estimated reduction rate 5%, 10%, 15%, show that the efficiency ratio of health education have an effect on producing benefits. It is estimated that more benefit can be produced if more qualitative education will be provided for enhancing health care efficiency. 7. Results of this study cannot be generalized because there are large scale of deviation in case of workplaces with less than 300 full time workers, but B/C ratio reads 2.69 as a whole and 3.25 at workplaces with their own health care manager are higher than 1.63 at the workplaces manged by the agencies. Finally, all the benefit concerning health care services could not be quantified, measured and shown on the value of money. This is a reason that a considerable part of benefits are so underestimated. This is also thought that measurement tools should be developed for measuring benefits of health care services with a comprehensive quantification. in the future. It is also expected that efficiency of occupational health care services should be investigated using cost-effectiveness analysis.

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비도시 정주지의 탄소중립 기여도 분석 - 농촌지역 그린인프라를 대상으로 - (Analysis of Contribution to Net Zero of Non-Urban Settlement - For Green Infrastructure in Rural Areas -)

  • 이동규;안병철
    • 한국조경학회지
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    • 제50권3호
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    • pp.19-34
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    • 2022
  • 본 연구는 비도시 정주지에 해당하는 농촌지역 그린인프라에 대한 탄소중립 기여도를 정량적으로 분석하여 비도시 정주지에 대한 탄소중립 정책 및 이행방안 수립시 활용할 수 있는 기초자료를 제공하기 위하여 진행하였다. 주요 목적은 첫째, 농촌지역 그린인프라를 체계화하고, 둘째, 그린인프라 요소별 원단위를 도출하며, 셋째, 이를 활용하여 우리나라의 탄소중립에 미치는 영향을 정량화하여 제시하는 것이다. 본 연구에서는 선행연구 조사 및 분석을 통해 도출된 농촌지역 그린인프라 요소에 대한 적정성 검증을 위하여 내용 타당도(CVR) 분석을 실시하였고 그린인프라 요소별 탄소감축량 원단위는 관련 분야 연구 결과를 활용하였으며 그 결과는 다음과 같다. 첫째, 농촌지역 핵심기능(Hubs)의 그린인프라는 마을숲, 습지, 농경지, 스마트팜, 연결기능(Links)은 하천, 마을녹지, 빗물 재활용시설이 .500 이상의 CVR값을 가지는 것으로 나타나 적정한 것으로 분석되었다. 둘째, 그린인프라 요소별 원단위는 선행연구 결과를 활용하여 최소값, 최대값, 중간값으로 구분 제시하여 탄소중립을 위한 공간적 계획, 설계 등에 활용될 수 있도록 하였다. 셋째, 농촌지역 그린인프라를 우리나라 비도시지역 정주지에 적용할 경우 최소 70.76 백만 톤, 최대 141.16 백만 톤에 달하는 CO2 를 간접적으로 감축하는 효과가 있는 것으로 분석되었다. 이는 2019년 농업부문 탄소배출량의 3.4배에서 6.7배에 달하는 양으로 탄소중립 기여도가 매우 높다고 볼 수 있으며, 이를 활용한 경제적 가치는 최소 약 1조 6천억 원에 달하여 농촌지역 활성화, 녹색일자리 창출, 농촌 산업생태계 전환 등에도 크게 기여할 수 있을 것으로 예상된다. 본 연구는 비도시지역의 정주지에 대한 탄소중립 기여도를 정량적으로 제시하였으며, 농촌지역 그린인프라 각 요소별 탄소감축 원단위를 도출함에 따라 마을단위의 탄소중립을 위한 공간적 계획, 설계 시 활용할 수 있는 기초연구로서 의의를 가진다. 특히, 그린인프라 요소별 탄소감축 원단위는 마을단위 탄소중립 정책, 계획 수립 시 정량적 목표제시 및 달성 여부 점검 등에 활용가능할 것이며 이를 기반으로 하여 시군구 등 지역단위와 도시단위의 탄소중립화에 확대 적용할 수 있을 것이다.

국민식생활(國民食生活) 향상(向上)을 위(爲)한 곡류제품(穀類製品)의 경제적( 經濟的) 영향강화(營養强化)에 관(關)한 연구(硏究) (A Study on the Economical Nutrition Supplement of Cereal Food for Improvement in our National Eating Habits)

  • 주진순;유종열;김숙희;이기열;한인규
    • Journal of Nutrition and Health
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    • 제6권1호
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    • pp.1-9
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    • 1973
  • I. Subject of the Study: Studies on the economical nutrition supplement of cereal foods for the improvement in our notional eating habits. II. Purpose and Importance of the Study: 1. Our nation is confronted with the situation that the rice, a principal food, short of some essential amino acids, lysine and threonine, leads to imbalanced meals insufficient in the nutrient of protein, to bring many difficulties in the elevation of our national physique. 2. The shortage of even the rice imperfect in the nutrient of protein makes the import of lots of foreign rice inevitable. It is considered that the protein supplement and decrease in the consumption amount, of rice, is a serious key to the solution of our food difficulty, and then a way of the proetin supplement of rice through the addition of essential amino acid is to be rarely applied in the view of the our present finance and situation. 3. In the present experiment, therefore, it aims to the suggestion of an aspect of the improvement in our national eating habits guiding in the nutrition elevation which our nation can afford economically through the development of first, a way of the protein supplement by the mixture of cereals producted plentifully in our country, and second, a way of the decrease in the consumption amount and the improvement in the nutrition of rice through the substitution of the other cereals for rice. III. Contents of Scope of the Study: 1. Objects of the study: Objects of the study are the following three items; a) The nutrition supplement of rice through the mixture of cereals. Our nation makes mainly rice as a principal food, but practically many kinds of cereal are produced in our country. They contain different levels and qualities of each nutrient and they are different from one another in the kinds of essential amino acid consisting protein. For that reason, the mutual complement efficeincy of insufficient nutrients is observed through the mixture of cereals. b) The nutrition supplement of rice through the addition of superior protein sources to rice, a principal food. The development of rice as superior foods in the sense of nutrition is conducted through the risement in protein quality by the addition of protein sources in good quality, for example, fish flour (anchovy flour), egg powder, milk powder, and so on, and through the supplement of vitamins and minerals. c) The decrease in the consumption amount of rice through the substitution of the other cereals for rice, as a principal food. The compensation for the short amount of rice is made by the reduction in the consumption of rice through the discovery of a way of substitution of the other cereals for rice, as a principal food and of the settlement of problems in nutrition and finance subsequent to this. 2. Contents of the study: a) An ideal mixture-ratio of cereals is established for rats by feeding mixed foods(rice-barely or rice-wheat) containing 5%, 15%, 25%, 35% and 45% level of either barely or wheat. b) The nutritive value is determined in the whole subsititution of other foods for rice, and then, a way of the complement of over and under nutrients is devised. c) The ideal combination is investigated for rats through feeding mixed foods of main food, rice and supplement foods of protein sources, soy bean, fish flour, egg powder and milk Powder. d) According to results from the above three experiments, the concise functional test for men and the examination of economical property are made. 3. Scope of the study: a) The observation of the effect of each diet on the growth rate for rats. The growth rate of rats was observed for 15 groups of mixed foods of a main food, rice, and wheat flour, barley powder or soy bean powder, respectively, and 12 groups of wheat flour diets supplemented with $1{\sim}3%$ milk powder, and rice or wheat flour diets supplemented with 5% of milk powder, egg powder, fish flour or soy bean powder, respectively. b) The determination of food consumption. The food consumption was determined at weekly intervals for 27 kinds of diet described in a) item. c) The determination of food efficiency rate. The food efficiency rate for each diet was determined by calculation from the gained body weight and the food consumption amount at the same intervals described in b) item. d) The determination of protein efficiency rate. The protein efficiency rate for each diet was determined by calculation form gained body weight and the protein amount of the food consumption amount at the same intervals described c) item. e) The determination of the body component. The hematocrite and hemoglobin levels in the blood, total nitrogen in the serum, blood sugar, and lipids and glycogen in the liver were determined. f) The observation of nitrogen balance. As a means of the observation of nitrogen balance, the total nitrogen in the urine was determined. g) The analysis of economical property. The economical property was analyzed as the gained body weight to the amount equivalent to one won through the conversion of the food consumption amount into money. h) The functional test for men. The concise functional test for men was made in order to establish if the best diet for experimental animals can be applied to men. IV. Results of the Study: The national food product plan, nationwide nutritive enlightment and the improvement activities in our country eating habits, especially, mixed and powder food problems are to be significantly referred, and the following results must be applied. a) In the mixed foods of cereals, the mixed food of the rice-barley containing $5{\sim}15%$ level of barley is best in terms of nutrition. b) The addition of superior protein sources, egg, Bilk, soy bean, or fish, respectively to either rice or wheat flour makes a great risement in the nutritive value. c) The animal protein is more effective in the elevation of nutritive value of cereals. d) Rice takes the most nutritive operation and has the highest preference, among rice, wheat flour and barley. e) Wheat flour is more economical than rice in evaluation of the gained body weight to the regular money, and the addition of fish or soy bean is more economical than that of any other supplement food. But the above results are true of the range of nutrition and economical property. f) The study on the nutrition composition and barley will lead to the improvement in our national eating habits as mixed food of the rice-barley containing $5{\sim}15%$ level of barley is more nutritive. g) This study on the nutrition only for the growing animal can not be considered as a perfect and entire evaluation. Consequently, the perfect data for our national nutrition can be obtained from the experiment similar to this for the much longer period examining, in details, the growth rate, change of physical strength, mental and bodily change, average life span, and resistance ability to infectious diseases.

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