• 한국지반공학회논문집
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• 제21권7호
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• pp.13-20
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• 2005

본 연구에서는 입도분포가 액상화 저항강도 및 동적물성치에 미치는 영향을 실험적으로 검증하였다. 우리나라 준설매립토의 입도분포 조사를 통해 준설매립토의 보편적인 평균입경 4가지와 균등계수 3가지를 선정하였고 평균입경과 균등계수를 각각 달리한 총 12종류의 대표적 준설매립토의 입도분포를 선정, 시료를 제작하였다. 제작된 시료를 이용하여 진동삼축시험을 수행하여 평균입경과 균등계수가 액상화 저항강도에 미치는 영향을 분석하였다. 또한 공진주시험을 수행하여 입도분포가 동적물성치에 미치는 영향도 분석하였다.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2008년도 추계 학술발표회 제20권2호
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• pp.625-628
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• 2008

도로공사에서 포장 콘크리트의 품질관리에 사용되고 있는 휨인장강도 시험체의 크기를 줄여 용이한 취급과 양생조의 활용도를 높이기 위해 시험체별 크기효과를 확인하고 이에 대한 보정계수를 도출하였다. 32mm 조골재가 사용된 본 실험에서는 별다른 크기효과를 관찰할 수 없었고, Bazant 등이 제안한 예측식에 실험결과를 적용하여 이를 확인할 수 있었다. 또한, 보정계수의 적용을 위해 도출된 예측식을무차원화하고 w/c와 압축강도의 관계를 도식화한 크기효과 보정 도표도 제안하였다.

• 한국추진공학회지
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• 제5권1호
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• pp.42-48
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• 2001

지난 20년 동안 인장하중과 굽힘 하중 상태에서 복합재료 적층판의 크기효과에 관한 많은 연구가 수행되었으며, 시편의 크기를 증가함에 따라 복합재 적층판의 강도가 저하되는 경향은 잘 알려져 있다. 그러나, 복합재 압축시험의 어려움으로 인해 압축하중 상태에서 시편의 파괴강도에 대한 크기효과에 관한 연구는 거의 수행되지 않았다. 본 연구에서는 홀을 갖는 복합재의 압축 강도에 대한 크기 효과를 고찰하기 위해 T300/924C, $>[45/-45/0/90]_{3S}$를 사용하였으며, 시편의 크기 변화를 위해 2차원면적 변화(시편의 폭 및 길이 변화)를 고려하는 평면 스케일링 방법을 사용하였다. 실험 결과는 유한폭을 가지는 평판에 대한 명확한 홀 크기 효과를 보였을 뿐만 아니라, 같은 a/W(홀 직경/시편 폭)를 갖는 시편에서도 크기 효과를 확인할 수 있었다. 반면에, 홀이 없는 시편은 명확한 강도 크기 효과를 보이지 않았다.

• 한국의류학회지
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• 제32권1호
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• pp.123-133
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• 2008

The purpose of this study is to analyze dissatisfaction and size appropriateness of the women with big breast for design the high functional big size brassiere. The data were collected from 179 women(between the ages of 20 and 39) residing in Gwang-ju using a questionnaire to purchase, wearing comfort, dissatisfaction of the size, wire and the pad of the big size brassiere. The data were analyzed with Chi-square test, t-test and ANOVA using statistical program SPSS 12.0. The results of this research are as follows; 1) Seven-two-point-two percent of the women with big breast more than C cup size polled said they had difficulty in looking for the suitable size of the brassiere and they usually weared the smaller size than the their own size. As a result, they felt inconvenience for the discord with the nipples and lack of the shape revision. 2) According to the result of the correlation analysis, breast size and Rohrer's index showed low correlation. 3) After dividing all respondents for this research into categories of the group of more than C cup and less than B cup the differences in responses were compared. The dissatisfaction with brassier were 'discord of cup size', 'pain due to the wire' and 'unnatural breast shape' in the group of more than C cup, compared to 'discord of cup size' and 'deformation of the wire and pad' in the group of less than B cup.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2001년도 추계학술발표회
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• pp.23-26
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• 2001

Batch test and column test were performed to develop the design factors for PRBs against the contaminated groundwater by ammonium and lead. Clinoptilolite, one of the natural zeolites having excellent cation exchange capacity(CEC), was chosen as the reactive material through the ion-exchange mechanism. In the batch test, the reactivity of Clinoptilolite to ammonium and lead was examined with varying the particle size of Clinoptilolite. The nit weight of Clinoptilolite showed removal efficiencies of 65 % against the ammonium and 98% against lead. The effect of particle size of Clinoptilolite was not noticeable. In the column test, the permeability was examined using flexible-wall permeameters with varying the particle size of Clinoptilolite. When the washed Clinoptilolite having the diameter of 0.42-0.85 nm was mixed with Jumunjin sands in 20:80 ratio (w/w), the highest permeability of 2$\times$10$^{-3}$ -7 x 10$^{-4}$ cm/s was achieved. The reactivity and the strength property of the mixed material were investigated using fixed wall column having 8 sampling ports on the wall and the direct shear test, respectively. Clinoptilolite was found to be a suitable material for PRBs against the contaminated groundwater with ammonium and/or heavy metals.

• Journal of the Korean Wood Science and Technology
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• 제18권3호
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• pp.6-16
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• 1990

The objectives of this study were to investigate the relative effects of specific gravity and particle size on internal bond and tensile strengths and fracture toughness of particleboard and to compare mechanical strength with fracture toughness. The particleboard was manufactured with three different particle sizes at specific gravity levels of 0.6, 0.7, and 0.8 with a resin content of 10% based on oven dry weight. The results were summarized as follows: 1. Internal bond strength. fracture toughness in internal bond test. maximum tensile strength, and fracture toughness in tension test increased with the increase of specific gravity of particleboard. 2. As partcle size increased, internal bond strength, fracture toughness. maximum tensile strength. and fracture toughness in tension test increased. 3. The maximum tensile strength and fracture toughness appeared to be in a direct relationship, and then maximum tensile strength could be used for predicition of fracture toughness for tension test. 4. The fracture toughness in internal bond test was somewhat independent on induced crack length.

• 한국잠사곤충학회지
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• 제13권1호
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• pp.69-72
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• 1971

1. 연감시료량의 적정량을 알아보기 위해 200, 100, 50, 20, 10gr의 생사시료를 연감검사한 결과 각처리간에는 통계적차이를 인정할 수 없었으나 실제로 시료량의 과대 과소에 따른 측정 및 처리오차를 감안할 때 100gr 시료가 적정량이었다. 2. 섬도사를 이용하여 연감검사를 할 경우 꼬인 상태와 풀은 상태로 연감처리할 경우 탄산나트륨같이 제교력이 강한 정연제에서는 차이가 없었으나 Marseilles 비누같이 제교력이 약한 것은 연감율에 있서 현저한 차이가 있었다. 3. 5종의 정연제를 비교한 결과 합성세제와 국산 Marseilles비누와 통계적 유의차를 인정 할 수 없으므로 이와의 대체 이용이 가능하다. 4. 정연제의 제교력은 대체로 정연액의 PH가 클수록 크고 작을수록 작은 경향이 있다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 추계학술대회
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• pp.1240-1245
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• 2003

Reduced activation ferritic steel (JLF-1) is considered as a promising candidate material for blanket or first-wall structure of D-T fusion reactors. The fracture tests of fracture resistance curve (J-R curve) and $J_{IC}$ are desirable to investigate the exact fracture toughness of JLF-1 steel, since it has a high ductility. The fracture toughness of JLF-1 steel is affected by the configuration of test specimen such side groove, specimen thickness or specimen size. In this study, the fracture toughness tests were performed with various size(plane size and thickness) and various side groove of specimens. The test results showed the standard specimen with the side groove of 40 % represented a valid fracture toughness. The fracture resistance curve increased with increasing plane size and decreased with increasing thickness. However, the fracture resistance curve of half size specimen was similar to that of the standard specimen.

• International Journal of Fluid Machinery and Systems
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• 제7권2호
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• pp.60-67
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• 2014

In order to clarify the effect of inlet bellmouth size of semi-opened type axial fan on its performance and flow fields around rotor, fan test and flow field measurements using hotwire anemometer were carried out for 6 kinds of bellmouth size. As results of fan test, the shaft power curve hardly changed, even if the bellmouth size changed. On the other hand, the pressure-rise near best efficiency point became small with the bellmouth size decreasing. Therefore, the value of maximum efficiency became small as the bellmouth size decreased. As results of flow field measurements at fan inlet, the main flow region with large meridional velocity existed near blade tip when the bellmouth size was large. As bellmouth size became smaller, the meridional velocity at fan inlet became smaller and the one at outside of blade tip became larger. As results of flow field measurements at fan outlet, the main flow region existed near rotor hub side.

• 한국압력기기공학회 논문집
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• 제5권2호
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• pp.7-12
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• 2009

The flaws detected by the non-destructive surface test methods shall be sized by means of the volumetric test such as an UT(ultrasonic test) or an ECT(eddy current test) for the purpose of analyzing and repairing them. It is generally known that the ECT is a comparatively effective technique for the small size cracks which are located shallowly from the surface. On this study, the ECT technique was tried to size the depth of the crack-like EDM notches, and it is identified that the ECT is an appropriate depth sizing technique for the shallow cracks less than 3mm in the Martensitic CA6NM material.