• 태양에너지
• /
• 제18권3호
• /
• pp.217-228
• /
• 1998

축류비가 5이고 형상비가 7인 장방형(長方形) 노즐을 사용하여 연직 상향의 3차원 자유 충돌 수분류계를 구성하였다. 수평 충돌판에 상향의 장방형 충돌수분류가 충돌할 때, 보조수를 동반하지 않은 단일수분류 및 보조수를 동반하는 수분류에 대하여 노즐-충돌판 사이의 거리, 노즐출구 속도를 변수로하여 노즐의 긴변 방향과 짧은 변 방향에 대하여 전압 및 정압 분포를 측정하였다. 이때 충돌판상에서 정압이 영이 되는 국소 위치까지의 거리인 충돌 반폭을 구하고, 최고 압력을 나타내는 정체점을 기준으로 무차원 정압 분포식을 제시하였다. 또한 각 실험조건에서 정체점상에서의 충돌속도를 구하였으며, 충돌속도는 노즐-전열면간 거리가 증가함에 따라 감소하며 그 감쇄율은 삼차원 자유 분류의 특성감쇄 영역의 유동 특성을 갖는다.

• Steel and Composite Structures
• /
• 제6권6호
• /
• pp.493-512
• /
• 2006

The present paper summarizes the experimental research carried out at the "Politehnica" University of Timisoara, Romania, with the scope of investigating the influence of different column web stiffening solutions on the performance of beam-to-column joints of Moment Resisting Steel Frames. The response parameters, such as resistance, rigidity and ductility were examined. Five different types of panel web stiffening were compared with regard to a reference test. A quasi-linear relationship between the moment capacity and the total shear area of the web panel was observed from the experimental tests while the initial rigidity increased non-proportionally with the same area. Comparisons are presented of the experimental tests with the mathematical model developed by Krawinkler and with the model stipulated in Eurocode 3 Part 1.8. These comparisons showed a generally good agreement in the case of moment capacity, while the computed rigidities were always greater than the experimental rigidities.

• 대한화학회지
• /
• 제55권3호
• /
• pp.490-494
• /
• 2011

이산화탄소 방출을 줄이기 위해 포트랜드 시멘트 성분 일부를 시멘트 보충재를 혼합해준 시멘트의 제조에 대해 연구하였다. 이산화탄소를 0.18 kg $CO_2$/kg 정도 줄이기 위해 포트랜드 시멘트에 보충재를 20 wt% 정도 혼합하였다. 이 혼합시멘트의 압축 강도는 포트랜드 시멘트 ASTM C-150의 표준치를 초과하며, 28일간의 굳는 과정중에 37 MPa의 압축 강도를 가졌다. 혼합시멘트의 미세구조는 포트랜드 시멘트와 유사하였다.

• 한국식품저장유통학회지
• /
• 제15권2호
• /
• pp.274-279
• /
• 2008

해양심층수 간장 및 일반간장을 제조하여 항돌연변이원성과 세포독성을 측정하였으며 sarcoma-180 cell을 이용하여 in vivo에서 항암효과를 살펴보았다. S. typhimurium TA98과TA100 균주를 이용한 실험에서 모든 시료에서 돌연변이원성이 없었으며, 항돌연변이원성 실험에서는 직접변이원인 MNNG($0.4{\mu}g$/plate)의 경우 TA100 균주에서 해양심층수간장의 시료농도 $200{\mu}g$/plate에서 90.9%의 높은 억제효과를 나타내었으며 4NQO($0.15{\mu}g$/plate)에 대해서는 같은 시료농도에서 62.0%의 억제효과를 나타내었다. 그리고 4NQO의 경우 TA98 균주에 대해서 해양심층수 간장은 61.7%의 억제효과를 나타내었으며 모든 시료는 농도 의존적으로 억제하는 것으로 나타났다. 세포독성 효과를 알아보기 위하여 HeLa, Hep3B, AGS, A549와 MCF-7을 사용하였다. 각 시료 추출물의 암세포 성장효과를 조사한 결과, 해양심층수 간장이 1 mg/mL의 농도에서 각각 69.4%, 70.5%, 55.6%, 82.1% 및 73.2%의 억제율을 나타내었다. 그리고 해양심층수 간장은 고형암 성장 억제 실험에서 대조군에 비해서 40.9%의 고형암 성장 억제효과를 나타내었다.

• 한국항공운항학회지
• /
• 제13권1호
• /
• pp.43-49
• /
• 2005

There are several ways to mold the complex material, and it is divided to vacuum pack mold, compression mold, and hand lay up for a high molecular substance as a basic material. Moreover, it can be divided to general manufacturing (Single form) and mold manufacturing(Mold form) under normal temperature for Firefly. Firefly was manufactured with hand lay up and general manufacturing that using the foam core, glass fabric, and template without mold. However, mold manufacturing that is producing the surface by semi-sandwich using thin foam core and glass fabric then reinforce the inside with spar and rib is on developing. Mold manufacturing can make easy to production, standardize the quality, and possible to mass producing. In this paper, we present the mold producing process for canard aircraft "Firefly", and the problems and solutions during producing Firefly. Moreover, it complements the defect that the problems caused by master manufacturing error when produce several masters of a large part, and make the manufacturing process to be shortened by the replacement from the supplementary plate to the foam that is installed when producing lay up mold.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• 제33권2호
• /
• pp.171-175
• /
• 2011

Implant placement on the anterior mandible is considered a common and safe surgical procedure. However, severe hemorrhage can occur if branches of the sublingual artery, which run through the lingual cortical plate of the mandible, are damaged. Excessive hemorrhage caused by injury to the sublingual artery can result in life-threatening problems such as airway obstruction. A 54-year old male patient without any generalized systemic conditions was referred due to active bleeding after implant placement in the anterior mandible. Gauze compression with surgicel and bosimin were performed and hemostasis was achieved. The patient was discharged after 3 days without any supplementary bleeding.

• 대한정형외과학회지
• /
• 제56권1호
• /
• pp.26-33
• /
• 2021

목적: 슬관절 전치환술 후 발생한 대퇴 삽입물 주위 골절에 이중 금속판을 이용한 고정술 후 결과를 평가하고자 한다. 대상 및 방법: 2007년 10월부터 2013년 2월까지 슬관절 전치환술 후 발생한 대퇴골 삽입물 주위 골절 23예 중 Lewis와 Rorabeck의 분류상 II형으로 삽입물 이완은 없으나 과상부 분쇄골절이거나 골절선이 외상과까지 연장됐거나 주대(stem)가 있어 편측 고정만으로 골절부의 안정성을 얻을 수 없다고 판단한 경우에 내, 외측 이중 금속판을 이용하여 내고정술을 시행하고 최소 1년 이상 추시가 가능했던 13예를 대상으로 하였다. 환자의 평균 연령은 72세(65-82세)였고 여자가 11예, 남자가 2예였다. 수상 기전은 낙상이 9예, 교통사고가 4예였다. 류마티스관절염 1예를 제외하고 12예에서 골관절염으로 슬관절 전치환술을 받았고 3예에서 재치환술 등의 이유로 주대가 있었다. 슬관절 전치환술 후 골절 발생까지의 평균 기간은 28개월(1-108개월)이었고, 술 전 환자의 평균 골밀도는 T score -3.2 (-1.7에서 -4.4)였으며, 평균 추시기간은 23개월(12-65개월)이었다. 수술법은 골절부의 내측에 먼저 광근 하방으로 접근하여 해부학적 정복을 시행하고 금속판으로 내고정을 시행한 후 추가로 외측에 최소 절개법을 통해 잠김 압박 금속판을 사용하여 내고정하였다. 골유합 기간 및 합병증, 최종 추시 시 Hospital for Special Surgery Knee Score (HSS)를 평가하였다. 결과: 평균 골유합 기간은 17.4주(7-40주)였으며 2예에서 지연 유합이 발생하였으나 추가적 수술 없이 36주와 40주에 골유합을 얻었다. 1예에서 불유합이 발생하여 재고정술 및 자가골 이식술을 시행 후 3개월에 완전한 골유합을 얻었다. 최종 추시 시 전후방각형성은 평균 2.86도(0-4.9도), 내외반 각형성은 평균 1.67도(-1.2-4.9도)로 전체 예에서 부정 유합은 없었다. 최종 추시 시 슬관절 운동 범위는 평균 90도였고, HSS 점수는 평균 85점(70-95점)이었다. 결론: 슬관절 전치환술 후 발생한 대퇴골 삽입물 주위 골절 시 편측 고정만으로 골절부의 안정성을 얻을 수 없는 경우 이중 금속판을 이용한 내고정술은 안정적인 고정으로 빠른 재활이 가능하고 임상적으로 양호한 결과를 얻을 수 있는 방법으로 생각된다.

• 한국조경학회지
• /
• 제30권5호
• /
• pp.89-97
• /
• 2002

This report describes the first prize design of Midongsan Eco-park, which is located in Chungcheongbuk-do (North Chungcheong) province. Criteria of the winning design are as follows: 1) The design should include a neighborhood park as well as a portion of a green zone, in order to harmonize the area ecosystem, gradually assimilate the surroundings, and serve as an education tool for the public. 2) According to an analysis of area maps and a site-inspection, a preserved area, a buffer area, a restored area, and a developed area should be developed. In the buffer and restored areas, major facilities and activity spaces should be set up. 3) Observation trails should be accessible to visitors, and a variety of adventure programs should be available. 4) The eco-park should be designed to provide a habitat for the Gorani (Chinese water deer) which used to live around Midongsan. 5) For sensuous and vivid visitor experiences, diverse programs are to be designed to accommodate different seasons, visitor ages, and required time. Environment and eco-education are to be emphasized to maximize the effect of the eco-programs. 6) Optimal activities for visitors of different ages, optimal time intervals and eco-programs by age are also suggested. 7) Facilities are zoned into three sections according to level of development. Each section has a main area and supplementary areas for better understanding. 8) Nature-friendly arrangement of facilities and construction should minimize earthwork and adverse effects on the local ecology. Throughout the planning, the following things were learned: longer-term analysis including all season's observation is essential; planning, designing, bui Iding and managing should be based on this careful, extended observation. The contest should have taken plate over a longer period of time in order enable more detailed planing of the eco-park For improved management and activities, a volunteer system in linked with schools eco-institutions and NGOs should be developed with eco-interpreters.

• 대한용접접합학회:학술대회논문집
• /
• 대한용접접합학회 2009년 추계학술발표대회
• /
• pp.55-55
• /
• 2009

FGB(Flexible Glasswool Backing) Submerged Arc Welding has been one of the main welding processes for one side butt welding in shipbuilding industries, which can efficiently improve the welding productivity by the addition of a supplementary filler metal into the molten weld pool. As recent ships have become larger in size, the application of high tensile and higher grade of steels has been continuously increased. Single pass FGB SA welding process accompanies such a high heat input when welding thick plates that the mechanical properties of weld metal can be dramatically degraded. This study has been performed in order to obtain high toughness and tensile properties of high heat input FGB SA welds, and to evaluate the effect of alloy elements on their mechanical properties. To complete welding 25mm-thick EH36 grade steel plate by single pass, 1.2mm diameter and 1.0mm long cut wires has been distributed in the groove before welding, and three different test coupons have been made using C-1.5%Mn, C-1.8%Mn-0.5%Mo, and C-1.4%Mn-1.7%Ni cut wires to investigate the influence of nickel(Ni) and molybdenum(Mo) on the mechanical properties of welds. Test results showed that the addition of Ni and Mo effectively promotes the formation of Acicular Ferrite(AF), while significantly reducing the amount of Grain Boundary Ferrite(GBF) in weld metal microstructures, which resulted in a beneficial effect on low temperature impact toughness and strength.

• 대한물리치료과학회지
• /
• 제29권1호
• /
• pp.41-46
• /
• 2022

Background: The purpose of this study was to develop a sit-to-stand transfer assistive device, and to conduct a feasibility test. Design: A technical note. Methods and results: In this study, we developed a sit-to-stand transfer assistive device for the elderly and the disabled who have difficulty standing up independently from sitting positions. The sit-to-stand transfer assistive device allows the user to transfer the weight from a sitting position to a standing position while shifting the weight forward by grabbing and pulling a support stand. Ten healthy adults participated in the feasibility test of the device. Each participant used the developed sit-to-stand transfer assistive device and investigated supplementation through a brief interview. As a result of the feasibility test, the opinion was that the device could assist the sit-to-stand transfer to some extent. There were opinions that it needed a function to adjust the height of the knee protective plate in the sitting position according to the user's physical characteristics. Because of the inconvenience of operating the lock device for fixing the position and adjusting inclination, there was an opinion that the improvement for a locking device is needed. There were opinions that it would be better to reduce the size of the device due to its inconvenience of portability. Conclusion: In this study, we developed the sit-to-stand transfer assistive device for the elderly and the disabled who have difficulty standing up independently from sitting positions. In addition, it is considered that the upgrade of the device is necessary for the future since there are supplementary opinions on some points.