• 제목/요약/키워드: Table height

검색결과 288건 처리시간 0.025초

Study of modified Westergaard formula based on dynamic model test on shaking table

  • Wang, Mingming;Yang, Yi;Xiao, Weirong
    • Structural Engineering and Mechanics
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    • 제64권5호
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    • pp.661-670
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    • 2017
  • The dynamic model test of dam-reservoir coupling system for a 203m high gravity dam is performed to investigate effects of reservoir water on dynamic responses of dam during earthquake. The hydrodynamic pressure under condition of full reservoir, natural frequencies and acceleration amplification factors along the dam height under conditions of full and empty reservoir are obtained from the test. The results indicate that the reservoir water have a stronger influence on the dynamic responses of dam. The measured natural frequency of the dam model under full reservoir is 21.7% lower than that of empty reservoir, and the acceleration amplification factor at dam crest under full reservoir is 18% larger than that under empty reservoir. Seismic dynamic analysis of the gravity dams with five different heights is performed with the Fluid-Structure Coupling Model (FSCM). The hydrodynamic pressures from Westergaard formula are overestimated in the lower part of the dam body and underestimated in its upper part to compare with those from the FSCM. The underestimation and overestimation are more significance with the increase of the dam height. The position of the maximum hydrodynamic pressure from the FSCM is raised with the increase of dam height. In view of the above, the Westergaard formula is modified with consideration in the influence of the height of dam, the elasticity of dam on the hydrodynamic pressure. The solutions of modified Westergaard formula are quite coincident with the hydrodynamic pressures in the model test and the previous report.

Relationship between needle depth for lumbar transforaminal epidural injection and patients' height and weight using magnetic resonance imaging

  • John, Hyunji;Sohn, Kyomin;Kim, Jae Hun
    • The Korean Journal of Pain
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    • 제35권3호
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    • pp.345-352
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    • 2022
  • Background: Optimal needle depth in transforaminal epidural injection (TFEI) is determined by body measurements and is influenced by the needle entry angle. Physician can choose the appropriate needle length and perform the procedure more effectively if depth is predicted in advance. Methods: This retrospective study included patients with lumbosacral pain from a single university hospital. The skin depth from the target point was measured using magnetic resonance imaging transverse images. The depth was measured bilaterally for L4 and L5 TFEIs at 15°, 20°, and 25° oblique angles from the spinous process. Results: A total of 4,632 measurements of 386 patients were included. The lengths of the left and right TFEI at the same level and oblique angle were assessed, and no statistical differences were identified. Therefore, linear regression analysis was performed for bilateral L4 and L5 TFEIs. The R-squared values of height and weight combined were higher than the height, weight, and body mass index (BMI). The following equation was established: Depth (mm) = a - b (height, cm) + c (weight, kg). Based on the equation, maximal BMI capable with a 23G, 3.5-inch, Quincke-type point spinal needle was presented for three different angles (15°, 20°, and 25°) at lumbar levels L4 and L5. Conclusions: The maximal BMI that derived from the formulated equation is listed on the table, which can help in preparations for morbid obesity. If a patient has bigger BMI than the one in the table, the clinician should prepare longer needle than the usual spinal needle.

한국 대학도서관 가구의 표준화에 관한 인간공학적 연구 -서가${\cdot}$의자${\cdot}$책상${\cdot}$ 목록함을 중심으로- (Human Engineering Approach to the Standardization of Shelving, Chairs, Tables and Card Cabinets for College and University Libraries In Korea)

  • 손정표
    • 한국문헌정보학회지
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    • 제11권
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    • pp.3-42
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    • 1984
  • This is to establish a model of the standardization of shelving, chairs, tables and card cabinets for college and university libraries in Korea. The size of furniture was measured on the base of the analysis of the human factors, such as the standard size of human bodies of the college students in Korea, the scope of work area, the moving degree of muscles, the limit of the visual field, etc. The results of this study are as follows: 1. It is desirable that the standard shelf length should be 800mm. and the maximum . shelving height should not exceed 1,803mm. And it is desirable that the bottom shelf has a ground clearance of about $210\~390mm$. 2. It is advisable that the sloped shelving has the slope from about 1,000mm, or 930mm, and the gradient should be $19^{\circ}$ from the above mentioned sloping position and the bottom of each shelf. And it is desirable that the slope height of each shelf should be 77mm. 3. It is advisable that the seat area for users should be $410\~420\times420mm$, and the seat height should be $390\~0400mm$. 4. It is desirable that the table size per user should exceed $490\times880\~890mm$, and the table height should be $680\~690mm$. 5. It is advisable that each tray of the card cabinet should hold about 740 cards, and the depth should exceed 430mm. And it is desirable that the maximum height of card cabinets should be as follows: 60du(drawer units)-$1,400\~1,460mm$, 30du-1, 300mm, 15du-1,100mm. In addition, it is advisable that the 30du cabinet should accomodate 5 trays vertically and 6 trays horizontally for avoiding the worst working position rather than 6 trays vertically and 5 trays horizontally. 6. It is desirable that the height of sliding reference shelves in card cabinets, or consultation tables should be 900mm. But in the case of the sliding shelves, it is desirable to be as follows: 15du-900mm when the card cabinet height is more than 1,100, mm, but unnecessary when less than 1,100mm high, 30du-1,000mm, or 1,100mm in the case of $5\times6du$, but 900mm in the case of $6\times5du$, $60du-900\~950mm$ when the card cabinet height is $1,400\~1,460mm$.

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C-arm을 이용한 EVAR(Endovascular Aneurysm Repair) 시술시 Lead Curtain 설치에 따른 Staff의 피폭선량 감소에 대한 연구 (The investigation of the exposure dose reduction of the Staff according to the Lead Curtain installation in EVAR(Endovascular Aneurysm Repair) surgical operation using C-arm)

  • 유인웅;정재연;이관섭
    • 대한디지털의료영상학회논문지
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    • 제14권2호
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    • pp.33-38
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    • 2012
  • In EVAR procedure using long time C-arm, we studied exposure dose reduction and effeciency through measuring surgical staff's ESD by installing lead curtain operating table next to. The height 3 the spot (50cm, 100cm, 150cm) dose was measured on 2 locations for 600sec in the X-ray radiation considering the surgical staff's movement. To install the curtains, we compared before and after the dose. As a result, it can confirm that dose of the installation former of 50cm height and after is reduced about 75% and 91% in 2 locations. In 100cm height, the reduction of the dose was a bit confirmed. There as to dose value, measured on 150cm height the installation former and after was nearly no change. This research examined the exposure dose about the radiation of the surgical staff during EVAR procedure in which the operation time is the long time. It was implemented in the object that it reduces the radiation exposure. It could confirm the certain effect of the experimental result exposure dose reduction In EVAR procedure using long time C-arm, we studied exposure dose reduction and effeciency through measuring surgical staff's ESD by installing lead curtain operating table next to. The height 3 the spot (50cm, 100cm, 150cm) dose was measured on 2 locations for 600sec in the X-ray radiation considering the surgical staff's movement. To install the curtains, we compared before and after the dose. As a result, it can confirm that dose of the installation former of 50cm height and after is reduced about 75% and 91% in 2 locations. In 100cm height, the reduction of the dose was a bit confirmed. There as to dose value, measured on 150cm height the installation former and after was nearly no change. This research examined the exposure dose about the radiation of the surgical staff during EVAR procedure in which the operation time is the long time. It was implemented in the object that it reduces the radiation exposure. It could confirm the certain effect of the experimental result exposure dose reduction.

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Shaking Table Model Test of Shanghai Tower

  • Lu, Xilin;Mao, Yuanjun;Lu, Wensheng;Kang, Liping
    • 국제초고층학회논문집
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    • 제2권1호
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    • pp.79-83
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    • 2013
  • Shaking table test is an important and useful method to help structural engineers get better knowledge about the seismic performance of the buildings with complex structure, just like Shanghai tower. According to Chinese seismic design guidelines, buildings with a very complex and special structural system, or whose height is far beyond the limitation of interrelated codes, should be firstly studied through the experiment on seismic behavior. To investigate the structural response, the weak storey and crack pattern under earthquakes of different levels, and to help the designers improve the design scheme, the shaking table model tests of a scaled model of Shanghai tower were carried out at the State Key Laboratory of Disaster Reduction in Civil Engineering, Tongji University, Shanghai, China. This paper describes briefly the structural system, the design method and manufacture process of the scaled model, and the test results as well.

다공성 패드를 갖는 챔버의 배열에 따른 공기 부상 테이블의 비접촉 부상 수준에 대한 연구 (Non-Contact Level on Air Levitation Table with Porous Chamber Array)

  • 김준현;정영석;이태걸;김태훈;정효재
    • 한국생산제조학회지
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    • 제22권6호
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    • pp.913-920
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    • 2013
  • This paper presents an applicable basic design that can configure non-contact levitation table for conveying a large sheet of glass. The suggested air levitation table consists of a series of air chambers with porous pads and fans as the conveyor system. The air supply chambers are arrayed to supply an adequately strong upward airflow for supporting the glass. Levitation is controlled by the size and discharge velocity, of the chamber arrays, as well as the glass supporting height. After pre-evaluation of the glass rigidity and the filer functional performance, a one-way fluid structure interface (FSI) analysis is performed for predicting pressure and deflection working of the 8G glass in the transverse and longitudinal directions, respectively. After comparing calculated levels of flatness of the glass, it determines the chamber array for the linear non-contact conveying motion.

노내 핵계측 검출기 안내관 인출 및 삽입용 자동화 시스템 설계 (Development of Thimble Handling Equipment for Nuclear In-Core Flux Mapping System)

  • 조병학;변승현;박준영
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2005년도 학술대회 논문집 정보 및 제어부문
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    • pp.225-227
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    • 2005
  • The in-core neutron Flux Mapping System in a pressurized water reactor yields information on the neutron flux distribution in the reactor core at selected core locations by means of movable detectors. The obtained data are used to verify the reactor core design parameters. The detector cables run through guide tubes(thimbles), and typically thirty-six to fifty-eight thimbles are allocated in the reactor depending on the number of fuel assemblies. These thimbles are inserted into nuclear fuel assemblies through conduits connected from the bottom of the reactor vessel to a seal table. During the plant refueling outage period, the thimbles are withdrawn up to 4m from the seal table, the height of a nuclear fuel. In spite of their importance, however, the thimble handling work has been performed by only human operators. In addition, its efficiency is very low due to narrow working environments on the seal table, thereby resulting in the excessive radiation exposure of maintenance personnel. To solve these problems, a new thimble handling equipment for in-core flux mapping system was developed, and we confirmed its effectiveness through experiments.

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구조 특성을 반영한 인간형 로봇을 위한 실시간 CoM/ZMP 궤적 변환 방법 (Real-Time CoM/ZMP Trajectory Transformation Method for Humanoid Robots Considering Structure Characteristics)

  • 홍석민
    • 한국항행학회논문지
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    • 제21권1호
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    • pp.132-137
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    • 2017
  • 본 논문에서는 로봇의 구조나 보행 상황을 반영해 하나의 보행 패턴을 다른 보행 패턴으로 변환하게 해주는 영모멘트 점 (ZMP; zero moment point)와 질량 중심 (CoM; center of mass)의 실시간 변환 방법을 제안한다. 일반적으로 휴머노이드 로봇은 높이와 질량과 같은 자체적인 구조 특성을 가지고 있다. 이러한 구조적 특성으로 인해 인간 또는 휴머노이드 로봇으로부터 측정되거나 생성되어진 CoM / ZMP 보행 패턴을 다른 로봇에 직접 적용하는 것은 어렵다. 이를 위하여 간단한 휴머노이드 로봇 모델인 cart-table model을 사용해 보폭의 길이, 보행 시간, CoM 높이 변화에 따라 보행 패턴의 특성을 분석한다. 그러한 분석으로부터 변환 방정식을 유도하고 시뮬레이션을 통해 제안된 방법을 검증한다.

Actual Conditions of Lighting Environment of Kitchen and Washroom Spaces in Houses between China and Korea

  • An, Ok-Hee;Jia, Hao;Lee, In-Hyo;Kim, Hyun-Ji
    • 조명전기설비학회논문지
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    • 제25권3호
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    • pp.1-6
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    • 2011
  • To compare the lighting environment of kitchen and bathrooms in the apartments in China and Korea, this research conducted a study of the current status, targeting 68 households in China and 79 households in Korea. The results are as follows. First, the Korean kitchen space is a little bigger than China's, but the height of the sink and table show no difference. China does not use local lighting in the kitchen. And Korea 40.2[%], China 65.6[%] is sink's KS based was below. In the case of the dining table, KS criteria satisfy both Korean and Chinese standards. 20[%] appear to be very feeble; urgent improvements are required. Secondly, regarding the size of the bathroom, Korea and China show similar sizes; the average height of the vanities and toilet is higher in Korea than in China by 2[cm]. China does not use local lighting in the bathroom. The levels of illumination were measured; lighting is higher in China's bathrooms compared to Korea's.

40평형 아파트 식생활용품 수납실태에 따른 부엌가구디자인 (The Kitchen furniture design Based on Stored items of Cooking Area in 40-pyung type apartment Houses)

  • 김기인;김선중;권명희
    • 한국주거학회:학술대회논문집
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    • 한국주거학회 2009년 춘계학술발표대회 논문집
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    • pp.304-309
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    • 2009
  • The purpose of this study is to develop kitchen furniture design for 40-pyung apartment Houses based on stored item of Cooking, Eating and Utility Area. The research data is gotten at a field study of stored items of Cooking, Eating and Utility Area and depth interview. The results of this study were as follows; 1)The kitchen furniture the preparation unit and the sink, the kitchen table, the heating unit and the service table, arranged at the tall storage. 2)The total bulk considered and holding volume ($2.7m^3$) with ground clearance (40%) planned with about $4.21m^3$. 3)Assumed at height and 162cm did a lower part height with 860mm and the upper depth 340mm, did with 700mm where raises. the storage the ceiling which raises will select and considered and with 2200mm did. 4)Arrangement of the kitchen the kitchen form which is an open type (L/DK or L.D.K) arranged many in forms of letter.

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