• 제목/요약/키워드: Draw-down

검색결과 85건 처리시간 0.032초

Effects of geometric shape of LWSCR (lazy-wave steel catenary riser) on its global performance and structural behavior

  • Kim, Seungjun;Kim, Moo-Hyun
    • Ocean Systems Engineering
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    • 제8권3호
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    • pp.247-279
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    • 2018
  • This study aims to investigate the behavioral characteristics of the LWSCR (lazy-wave steel catenary riser) for a turret-moored FPSO (Floating Production Storage Offloading) by using fully-coupled hull-mooring-riser dynamic simulation program in time domain. In particular, the effects of initial geometric profile on the global performance and structural behavior are investigated in depth to have an insight for optimal design. In this regard, a systematic parametric study with varying the initial curvature of sag and arch bend and initial position of touch down point (TDP) is conducted for 100-yr wind-wave-current (WWC) hurricane condition. The FPSO motions, riser dynamics, constituent structural stress results, accumulated fatigue damage of the LWSCR are presented and analyzed to draw a general trend of the relationship between the LWSCR geometric parameters and the resulting dynamic/structural performance. According to this study, the initial curvature of the sag and arch bend plays an important role in absorbing transferred platform motions, while the position of TDP mainly affects the change of static-stress level.

관개용 관정의 양수량과 영향인자들의 상관관계에 관한 연구 (A Study on the Correlation between Pumping Rates and Influential Factors in Tube Wells for Irrigation)

  • 류한열;구자웅
    • 한국농공학회지
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    • 제16권2호
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    • pp.3410-3419
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    • 1974
  • The purpose of this study is to find out the correlation between pumping rates and influential factors in the tube wells for irrigation through the analysis of various statistical data of the existing tube wells for irrigation and pumping tests. Statistical data of the existing tube wells for irrigation were collected from the authorities concerned, and pumping tests were carried out for twelve tube wells. The results of this study are summarized as follows: 1. The drilled tube wells are the most useful among various tube wells in securing pumping rates. 2. The enlargement of well diameter or the improvement of pumping equipments is necessary in drilled tube wells with pumping rates more than 806 ㎥/day, and the adjustment of foot valves or the special control of pumping equipments is necessary in tube wells with pumping rates less than 300 ㎥/day. 3. The choking of aquifer and slits can be prevented by removing earth and sand piled in tube wells. 4. The increase of well loss and the destruction of aquifer can be prevented by determining the optimum pumping rates through the step draw down tests. 5. The thickness of gravel packing is rather thin in drilled tube tube wells. 6. High pamping rates can be gained by deepening the depth of tube wells in the place the ground water storage is abundant, the thickness of aquifer is thick. and the depth of tube wells is deep. 7. Higher pumping rates can be obtained by constructing tube wells in the place where the drawdown is little and the coefficient of transmissibility is large.

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저출산 대책에 대한 다학제적 접근 (Multidisciplinary Approach to Low Fertility Issue in Korea)

  • 박정한
    • 보건행정학회지
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    • 제28권3호
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    • pp.233-239
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    • 2018
  • A rapid decrease of total fertility rate to 1.08 in 2005 prompted the Korean government to plan and implement a '5-year plan for ageing society and population policy' starting from 2006. The 1st and 2nd 5-year plans had not shown any discernible impact on the fertility and the 3rd 5-year plan was launched in 2016. However, the fertility rate is going down further. The author reviewed the contents and assessment reports of the fertility promotion plan to suggest ideas for complementing the shortcomings of it. Author defined the major determinants of marriage and child birth as philosophy, politics, sense of value, social norm, culture, healthcare, and education. The plan was examined in view of these determinants. Transformation of Korea from an agricultural society to an industrialized society in a short period of time had brought about changes in most of the determinants of marriage and child birth; in particular philosophy and sense of value. These aspects were not put into consideration in the plan. Author suggested to launch a social education program for the general public to establish a sound philosophy of life, reform the sense of value on family, child birth and education, and cultivate the skill to draw a consensus through discussions on the social issues. A special program to promote marriage of women at the optimum age for child birth was proposed. The government should implement well balanced policy for economic development and labor. Multidisciplinary approach was recommended for these tasks.

지역사회개발과 사회교육을 위한 개발커뮤니케이션 접근 (Development Communication Approaches to Community Development and Adult Education)

  • 전은경;김성수
    • 농촌지도와개발
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    • 제7권2호
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    • pp.359-376
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    • 2000
  • The purposes of this exploratory study were to interrelate the scholastic discipline of the ‘development communication’ into ‘community development’ and ‘adult education’ in terms of interests, views and theoretical backgrounds of these fields of social sciences; and to draw some implications for developing scholastic interactions among these fields to pursue common social changes of human society. Development communications provide opportunities to set goals, to decide contents, and to utilize communication media in developmental efforts. Contemporary trends of development communication, community development and adult education are concerned with indigenous, two-way, bottom-up and people-centered communication from exogenous, one-way, top-down and institution-centered communication of the past. Multidisciplinary approaches to communication concepts and methodology may increase the potentials of community development and adult education in terms of efficiency and effectiveness. Some of the development communication approaches such as traditional and folk media approach. new media or ICT(information & communication technology) approach, participatory communication for development approach, communication support development approach and mass media approach may be applicable for community development and adult education. Better understanding on development communication approaches will be needed for the adult educators as well as community development practitioners.

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문화재 복원 데이터 획득을 위한 사진 해석 (Image Analysis for Data Acquisition of Restore Cultural Assets)

  • 윤희천;손덕재;박준규
    • 한국측량학회지
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    • 제27권2호
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    • pp.273-279
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    • 2009
  • 문화재를 잘 보존하고 전승하는 것은 후손들의 몫이다. 현재 목조건물 형태의 문화재는 환경적 요인에 의하여 여러 번의 중수와 재건을 한 경우 대부분이다. 본 연구에 활용한 문화재는 11번의 중수와 재건을 한 것으로 초기의 모습이 많이 훼손되었다. 따라서 문화재청에서는 원형으로 복원을 하고자하였다. 그러나 원형 복원을 위한 자료로는 사진해석을 위한 자료가 없는 단 한 장의 사진만 존재한다. 본 연구에서는 자료부족으로 사진측량학적 해석을 하기 어려운 보물 제322호 관덕정의 1900년 이전 사진을 소실점을 이용한 기하학적 해석을 통하여 복원에 필요한 자료를 획득할 수 있었다. 또한 연구 결과로 획득한 자료는 실제 복원을 위한 기초 자료로 제공하였다.

Ergonomic Design of Necklace Type Wearable Device

  • Lee, Jinsil;Ban, Kimin;Choe, Jaeho;Jung, Eui S.
    • 대한인간공학회지
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    • 제36권4호
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    • pp.281-292
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    • 2017
  • Objective: This study aims to identify important physical design variables in designing a necklace type wearable device, and to present design guidelines to maximize comfort that a user feels upon wearing the device. Background: Interests in fitness culture and personal health are on the rise recently. In such a situation, demand for necklace type wearable devices is projected to increase a lot, as the devices enable users to use their hands freely and to enjoy various contents through connection with mobile devices. However, the necklace type wearable device's comfort was assessed to have the lowest comfort in a running situation, where human body moves up and down and left and right more than other devices wearable on other human body parts. Therefore, the usability of a necklace type wearable device was low. In this regard, studies on identification of the variables affecting user comfort upon wearing a necklace type wearable device and on physical design direction maximizing comfort and usability are needed. Method: A pretest and a main test were carried out to draw the direction of necklace type wearable device design. In the pretest, wearing evaluation on the diverse types of devices released in the market was conducted to draw physical design variables of the devices affecting comfort. Furthermore, variables significantly affecting the comfort of a device were selected through an analysis of variance (ANOVA). In the main test, anthropometry was performed, and information on anthropometric items corresponding to the design variables selected in the pretest was acquired. Based on the pretest results and the anthropometric information in the main test, the present study produced design guidelines maximizing the comfort of a necklace type wearable device with regard to major design variables upon dynamic tasks. Results: According to the pretest results, the variables having effects on comfort were the angle of side points, width, and height. Due to interactions between variables, those need to be simultaneously considered upon designing a device. Upon dynamic tasks, the angle of side points and width of a device was designed to be smaller than mean angle of the trapezius muscle and neck width, and thus attachment to human body was high. As height was designed to be larger than mean neck front and rear point width, comfort was higher due to feeling of stability. Conclusion: Because user sensitivity to comfort was high at human body's inflection points, a device needs to be designed for users not to feel high pressure on specific body parts with the device fitting human body shape well. A design considering user's situation is also required in further studies.

A study on Development of Footwear Shape Scanner for Off-Line Robot Path Programming

  • Lho, Tae-Jung;Song, Se-Hoon;Ju, Hyun-Woo;Lee, Jung-Wook;Cho, Jae-Kung;Ahn, Hee-Tae
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2003년도 ICCAS
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    • pp.808-812
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    • 2003
  • We need a lot of manpower and we can cut down a labor cost by applying industrial robots the footwear bonding automation process. In this study, we suggest how to program off-line robot path along a shoe's outsole shape in the footwear bonding process by 5-axis microscribe system like robot arms. This microscribe system development consists 5-axis microscribe mechanics, signal processing circuit, and PC with software. It is the system for making database of a shoe's outsole through the movement of a microscribe with many joints. To do this, first read 5-encoders' pulse values while a robot arm points a shoe's outsole shape from the initial status. Then, calculate a relative shoe's outsole by Denavit-Hatenberg's (D-H) direct Kinematics of known length of links and coordinate values. Next, calculate the encoders' pulse values of the robot arm's rotation and transmitting the angle pulse values to the PC through a circuit. Finally, it is able to display a shoe's outsole at real-time by computing the Denvavit-Hantenberg's (D-H) direct kinematics in the PC. With the coordinate values calculated above, we can draw a bonding gauge-line on the upper. Also, we can make off-line robot path programming compute a shoe's bonding area on the upper. These results will be effectively applied for programming a robot path on off-line and automatically.

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아유르베다의 정의와 인도전통의학과의 관계에 대한 고찰 (Study of Definition of Ayurveda and Its Relations with Indian Traditional Medicine)

  • 김진희;한창현;김남일
    • 한국의사학회지
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    • 제23권1호
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    • pp.1-10
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    • 2010
  • Ayurveda is one of the most historic and comprehensive medical system in the world. It was passed down as Buddhist medicine with Buddhism to influence enormously to East Asian medicine. Therefore, researches on Ayurveda is important in studying East Asian medicine as well as in studying Indian traditional medicine and althernative medicine. However, in previous studies, the term, 'Ayurveda', was mistaken and misused frequently. Clarifying the relations between the definition of Ayurveda and Indian traditional medicine is essential in preventing future controversy. Therefore, such relations were studied to draw following conclusions. 1. 'Ayurveda' is the term determining the oldest medicine system in the world that originated in India. Reportedly, the first book about Ayurveda is "Agnivesha samhita", and the oldest existing book is "Charaka Samhita". No records were found on medine books named Ayurveda, and interpreting Ayurveda to be a name of a book is explicitly misunderstanding. 2. There are various divisions of Indian traditional medicine in previous studies. However, divisions in 6 types of Ayurveda, Siddha, Unani, Yoga, Naturopathy and Homoeopathy is the most proper. 3. Ayurveda gained some similarities as it exchanged with other medicine systems. However, since each medicine system has unique characteristics, they must be separately studied. Especially, current Indian traditional medicine system has many divisions. Terms of 'Indian traditional medicine' and 'Ayurveda' must be separately used.

재택근무자를 위한 홈 오피스 가구디자인에 관한 연구 (A Study on The Furniture Design for Home Office Worker)

  • 양영완
    • 디자인학연구
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    • 제11권2호
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    • pp.17-28
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    • 1998
  • 오피스의 개념이 바뀌면서 그 기능과 역할이 축소되고, 가정이 곧 사무실 화하는 업무형태가 주목을 받고 있다. SOHO(Small Office Home Ofice)라고 불리우고 있는 '가정내의 사무실' 즉 '홈 오피스'는 정보통신기술의 발달로 인해 가능해졌고, 기업의 리스트럭처링(Restructuring)붐을 타고 날로 확산 추세에 있다. 재택 근무 형태는 직원에게 여유 있는 시간과 집중력을 배가시킨 업무효율을, 기업에는 고정비용의 감소와 생산성 향상을 제공한다. 또한 교통문제나 환경문제를 해소할 수 있고, 여성이나 고령자, 장애자 등의 잠재 노동력을 활용할 수 있는 장점도 있다. 향후 업무형태의 주종을 이룰 것으로 예상되는 홈 오피스의 공간계획, 가구배치 등 디자인상의 문제를 연구하여 재택 근무자 들에게 효율적인 업무수행을 높이고 창조적인 환경을 제공하는 것이 무엇보다도 중요하다. 또한 합리적인 홈 오피스 가구디자인을 위해서는 건축, 인테리어 디자이너는 물론 정보통신 전문가, 고용문제 전문가 등 관련 분야의 전문가들이 공동으로 연구 추진되어야 할 것이다.

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방사형집수정에 의한 강변여과수 수위하강 특성 (Draw-down Characteristics of Bank Filtration by Using the Horizontal Collector Well)

  • 정지훈;박재현;박창근;양정석
    • 한국수자원학회:학술대회논문집
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    • 한국수자원학회 2005년도 학술발표회 논문집
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    • pp.240-244
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    • 2005
  • 현재 강변여과수 개발은 수직정 위주로 개발되어졌으나, 수직정을 이용한 취수 방식은 산출량에 대한 한계를 가지고 있어 대용량 취수를 위해서 많은 취수정 착정이 불가피하다. 취수정 증가와 더불어 유지관리상의 문제점을 가지고 있으며 실제 운영에서 문제점이 나타나고 있는 실정이다. 이러한 수직정 취수정의 문제점을 해결하기 위해 방사형 집수정을 이용한 강변여과수 개발이 시도 되고 있다. 현재 창원시 대산면 일대에서 국내최초로 방사형집수정을 이용한 강변여과수 개발이 진행되고 있으며, 현재 방사형 취수정 1기가 시공 완료되어 시험 가동 중에 있다. 방사형 집수정에 의한 강변여과수 개발은 대용량 취수를 목적으로 설치되기 때문에 산출량뿐만 아니라 집수정 인근의 수위하강에 특성이 중요한 요소 중에 하나이다. 본 연구에서는 창원시 대산면 일대에서 진행되고 있는 방사형 집수정 설치에 따른 강변여과수 산출시 집수정 인근 수위하강 특성 파악을 위한 모니터링을 목적으로 실시하였다. 수위하강 특성 관측을 위해 양수실험을 위해 대용량 양수펌프 설치, 유량검증을 위한 대형 웨어 설치, 수위변화 측정을 위해 집수정 30m 반경에 8개의 관측정을 착정하여. 디지털 수위측정기를 설치하여 수위하강 특성을 모니터링 하였다. 수위 모니터링 결과 취수정의 수위하강 특성과 유사하게 수평정의 수위하강 경향 나타났으며, 강변에 가까운 수평정의 수위하강은 약 $30\% 감소하였으며, 집수정 양수량에 변화에 따라 민감하게 반응하지 않는 특성을 나타냈다.

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