• Title/Summary/Keyword: opening width

검색결과 225건 처리시간 0.027초

UHPC의 직접인장응력과 균열개구변위와의 관계에 관한 실험적 연구 (Experimental study on the relationship between direct tensile stress and crack opening displacement of UHPC)

  • 강수태;박정준;류금성;고경택;김성욱
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2008년도 춘계 학술발표회 제20권1호
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    • pp.433-436
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    • 2008
  • 초고성능 콘크리트의 재료적 특성을 평가하는데 있어 무엇보다도 인장거동의 평가가 우선적으로 수행되어야 한다. 일반적으로 콘크리트의 인장거동은 균열이전의 탄성거동과 균열이 발생한 이후의 응력과 균열폭과의 관계 특성에 의해 정의되어진다. 본 연구에서는 초고성능 콘크리트에 대해 직접인장실험 및 휨인장실험을 수행하고 휨인장실험 결과의 역해석을 통해 얻은 인장거동과 직접인장실험을 통해 구한 인장거동의 상관관계를 파악하였다. 또한 유사한 역학성능을 가진 초고성능 콘크리트에 대해 일본에서 제시하고 있는 초고성능 콘크리트 설계지침 중 인장거동 특성과의 비교평가를 실시하였다. 그 결과, 휨인장실험으로부터 역해석을 통해 구한 인장응력-균열폭 관계가 직접인장실험으로 구한 결과와 잘 일치함을 확인하였으며, JSCE에 제시하는 인장연화곡선과의 비교를 통해 본 연구에서의 초고성능 콘크리트가 유사한 연화거동을 보임을 확인하였다.

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Soboliphyme baturini (Nematoda: Soboliphymatidae) Recovered from Stomach of Asian Badger, Meles leucurus, in Geochang-gun, Gyeongsangnam-do, Korea

  • Sohn, Woon-Mok;Na, Byoung-Kuk
    • Parasites, Hosts and Diseases
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    • 제57권5호
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    • pp.521-524
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    • 2019
  • We are going to describe the female soboliphymid nematodes, which were recovered from the stomach of a Asian badger, Meles leucurus (Mammalia: Mustelidae), in Geochang-gun, Gyeongsangnam-do, Korea. In February 1998, we found 2 peculiar nematodes with a cup-like organ in the anterior end from the stomach of badger. Recovered worms were fixed with 10% formalin, cleared in glycerin-alcohol solution and observed under a light microscope with a micrometer. They were 34.46 (33.43-35.50) mm long by 2.13 mm at maximum width. Cephalic sucker cup-like, 3.34 (3.13-3.55) mm wide, 2.40 (2.25-2.55) mm long, with the oral aperture and meridionally striated on the buccal capsule. Oral aperture 2.38 mm in diameter. Circumoral membrane 0.41 (0.38-0.45) mm wide. Esophagus muscular, 4.81 (4.50-5.00) mm long by 0.80 (0.78-0.83) mm at maximum width. Vulva situated at 3.13 mm ventro-anterior level from the esophago-intestinal junction. Vagina anteriad, 3.38 mm long, making a canal from the uterus to the vulva opening. Uterus single, large. Tail 0.35 (0.33-0.38) mm long. Intrauterine eggs long elliptical, 0.058-0.065 (0.062) mm long and 0.030-0.033 (0.031) mm wide. Based on the some morphological characters and host-specificity, our specimens are nearly identical with S. baturini. Therefore, the present report describes S. baturini for the first time in Korea.

관통부의 철근 절단으로 인한 주변 철근의 응력분포 특성 (Stress Distribution Characteristics of Surrounding Reinforcing Bars due to Reinforcing Bar Cutting in Penetration)

  • 정철헌;문일환;이정휘;송재철
    • 대한토목학회논문집
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    • 제42권6호
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    • pp.775-786
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    • 2022
  • 원자력발전소 구조물을 포함하여 플랜트 구조물에서는 사용 중 설비보강을 위하여 벽체 및 슬래브에 관통부를 신설하는 경우가 빈번히 발생하고 있으며, 관통부 설치작업 중에 철근이 절단되는 사례가 일부 발생하고 있다. 이 관통부들은 설계 또는 건설 단계에서 고려된 것이 아니므로 설치 중 발생한 철근의 절단은 사실상 구조물의 손상이기 때문에, 관통부 주변 응력 전이범위 또는 유효폭을 고려한 구조물의 건전성 평가가 필요하다. 본 연구에서는 가동중인 원자력발전소 벽식 건물의 전단벽에 관통부를 신설할 경우에 발생하는 철근 절단의 영향을 평가하기 위하여 다양한 비선형 해석과 정적 가력 실험을 수행하였다. 그리고 관통부 신설과 철근의 절단으로 인한 벽체의 강성저하와 관통부 주변 철근의 응력 및 변형률 분포를 평가하였다.

Experimental study on multi-level overtopping wave energy convertor under regular wave conditions

  • Liu, Zhen;Han, Zhi;Shi, Hongda;Yang, Wanchang
    • International Journal of Naval Architecture and Ocean Engineering
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    • 제10권5호
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    • pp.651-659
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    • 2018
  • A multi-level overtopping wave energy converter was designed according to the large tidal range and small wave heights in China. It consists of two reservoirs with sloping walls at different levels. The reservoirs share a common outflow duct and a low-head axial turbine. The experimental study was carried out in a laboratory wave-flume to investigate the overtopping performance of the device. The depth-gauges were used to measure the variation of the water level in the reservoirs. The data was processed to derive the time-averaged overtopping discharges. It was found that the lower reservoir can store wave waters at the low water level and break the waves which try to climb up to the upper reservoir. The upper sloping angle and the opening width of the lower reservoir both have significant effects on the overtopping discharges, which can provide more information to the design and optimization of this type of device.

PS검층에 의한 터널굴착에 따른 주변암반의 이완영역 평가 (Estimation of Disturbed Zone Around Rock Masses with Tunnel Excavation Using PS Logging)

  • 박삼규;김희준
    • 자원환경지질
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    • 제31권6호
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    • pp.527-534
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    • 1998
  • Excavation of underground openings changes stress distribution around the opening. The survey of this disturbed zone in excavation is very important to design and construct underground facilities, such as tunnel, gas and oil storage, power plant and disposal site of high- and low-level radioactive wastes. This paper presents a zoning of rock masses with tunnel excavation using PS logging. Compressional and shear wave velocities are measured in boreholes drilled in the tunnel wall, which was constructed with blasting and/or machine excavation. The disturbed zone in excavation can be estimated by comparing PS logging data with a tomographic image of compressional wave velocity and compressional and shear wave velocities of core samples. In the side wall of tunnel, the disturbed zone reaches 1.5 m and 1.0 m in thickness for blocks of blasting and machine excavations, respectively. In the roof of tunnel, however, the disturbed zone is 1.0 m and 0.75 m thick for the two blocks. These results show that the width of the disturbed zone is larger in the side wall of tunnel than in the roof, and 1.3 to 1.5 times larger for the blasting excavation than for the machine excavation.

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연신내 성당 리모델링 구축 프로젝트 (Remodeling Project of the 'Yeonsinae' Catholic Church)

  • 배강희;이혁준
    • 한국실내디자인학회:학술대회논문집
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    • 한국실내디자인학회 2006년도 춘계학술발표대회 논문집
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    • pp.53-54
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    • 2006
  • Recently with increasing interest in the operation of life cycle, building remodeling business is spreading like a fashion. Keeping pace with the trend, the present project carried out the remodeling of an existing neighborhood facility into a religious facility based on the concepts of remodeling, reform and renovation. Basic requirements were overcoming spatial limitations, solving structural problems, meeting various functional needs, and securing a spatial size, and the project designed the interior of the building according to these requirements suggested by the owner. To overcome the low floor height of the existing space, the main sanctuary on the 1st floor had the ceiling in the form of a slant and installed indirect lighting into the resulting gaps, maximizing the depth and width of the space visually. The subsidiary sanctuary on the first basement was finished with red bricks, forming an arch using the bricks, to create religious atmosphere. However, considering the low floor height as in the 1st floor and the ceiling even lowered by the arch structure, the arch was formed threefold and the radius of the curvature of the arch was enlarged to secure a spacious feeling. The outer appearance was finished with granite on existing structure to save the cost of construction. In addition to the use of the finishing material, the structure of the arch and the frame of the opening part and the finishing of the walls were expressed with uneven surface in order to avoid the plainness of the appearance.

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Determination of double-K fracture parameters of concrete using split-tension cube test

  • Kumar, Shailendra;Pandey, S.R.
    • Computers and Concrete
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    • 제9권2호
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    • pp.81-97
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    • 2012
  • This paper presents development of double-K fracture model for the split-tension cube specimen for determining the unstable fracture toughness and initial cracking toughness of concrete. There are some advantages of using of split-tension cube test like compactness and lightness over the existing specimen geometries in practice such as three-point bend test, wedge splitting test and compact tension specimen. The cohesive toughness of the material is determined using weight function having four terms for the split-tension cube specimen. Some empirical relations are also suggested for determining geometrical factors in order to calculate stress intensity factor and crack mouth opening displacement for the same specimen. The results of double-K fracture parameters of split-tension cube specimen are compared with those obtained for compact tension specimen. Finally, the influence of the width of the load-distribution of split-tension cube specimen on the double-K fracture parameters for laboratory size specimens is investigated. The input data required for determining double-K fracture parameters for both the specimen geometries are obtained using well known version of the Fictitious Crack Model.

독서자원과 그 협력방안을 위한 시도적 연구-경상북도를 중심으로

  • 김남석
    • 한국도서관정보학회지
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    • 제3권
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    • pp.1-31
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    • 1976
  • If Y'ational developments are depend on the dex-elopment of regional >ociety and de~.elopment of regional society are rely on intellcctual delrelopment of members of regional society, going abreas! oi economic capacity. Estnhlis!l:r,ent of libraries as a treasure-house of mental resources and its Jet-elopment are inevit-able and important. But in every respect :f modern libraries are not equipped with contemporary devclij;!~i:c:\ulcornert of society. One c~i the resolving problems, like this, opening the door of the liI~-,\ulcornerr:~fa-c ilities, as one object, which located in every regional areas, u.9ng the existing facilities, the width of the library services mus: I)c opened. I-' ;- I n,> study is aimed at like the following: 1. is analysizing the situation ~vhich the library facilities of one ti:u~:sa!~d five hundred and fifty nine located here and there ir, Ii.;~-ui:gij~opkr ovince in Korea and s i s t ~t.l lousand seven hundred aid tliirl:~ six village libraries, for connecting as a library networks. 2. Tl\ulcornerc ivhole libraries in Kyungbook province and dividing into four ::arts as a Daegu, Phohang, Ahndong and Kimchun area as a transportation area, school area and resources area which exhibiting the view-point of helping-net~vorksl ike the following,

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인버터를 이용한 냉동용 압축기의 용량 제어 (Control of Refrigerating Compressor Capacity Using Inverter)

  • 양현석;김환성;김정훈;김상봉;김종수
    • 설비공학논문집
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    • 제5권2호
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    • pp.94-101
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    • 1993
  • Recently, efforts of decreasing energy consumption are continously increased and user's preference is also diversified in refrigeration and air conditioning systems. Thus, in order to satisfy these demands, high efficiency, high intelligence, and energy saving for those systems are essential. As the basic study for diverse functions and intelligence of those systems, we investigated the response characteristics through the compressor capacity control concerned with superheat and refrigeration room temperature. And, response characteristics are investigated experimentally by using micro computer based PWM inverter control method. Experimental result of the conventional on-off control method is given in order to be compared to the results of inverter control method. The results obtained through this study are summarized as follows. It is shown from the experimental results of the on-off control method that the range of temperature variation around the steady state ($-18^{\circ}C$) is very large (about $7{\sim}8^{\circ}C$) and the settling time bringing the steady state is not found. In the inverter control method, we can see that the refrigeration room temperature after reaching the setting temperature is very stable without fluctuation and a robust control for disturbance such as opening the door has been realized.

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MRI에 의한 모음의 성도 단면적 측정 및 면적 변이에 따른 합성 연구 (Measurement of the vocal tract area of vowels By MRI and their synthesis by area variation)

  • 양병곤
    • 음성과학
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    • 제4권1호
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    • pp.19-34
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    • 1998
  • The author collected and compared midsagittal, coronal, coronal oblique, and transversal images of Korean monophthongs /a, i, e, o, u, i, v/ produced by a healthy male speaker using 1.5 T MR, VISION. Area was measured by computer software after tracing the cross-section at different points along the tract. Results showed that the width of the oral and pharyngeal cavities varied compensatorily from each other on the midsagittal dimension. Formant frequency values estimated from the area functions of the seven vowels showed a strong correlation (r=0.978) with those analyzed from the spoken vowels. Moreover, almost all of 35 students who listened to the synthesized vowels from area data perceived the synthesized vowels as equivalent to the spoken ones. Movement of constriction points of vowel /u/ with wider lip opening sounded /i/ and led to slight changes in vowel quality. Jaw and tongue movement led to major volume variation with an anatomical limitation. Each comer vowel varied systematically from a somewhat constant volume of the average area. Thus, the author proposed that any simulation studies related to vocal tract area variation should reflect its constant volume. The results may be helpful to verify exact measurement of the vocal tract area through vowel synthesis and a simulation study before having any operation of the vocal tract.

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