• 제목/요약/키워드: least depth

검색결과 458건 처리시간 0.028초

터널 화재시나리오에 따른 콘크리트 PC패널라이닝의 열적손상에 관한 실험적 연구 (An Experimental Study on Thermal Damage under Tunnel Fire Scenario to Concrete PC Pannel Lining)

  • 김흥열;박경훈;김형준
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2008년도 추계 학술발표회 제20권2호
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    • pp.477-480
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    • 2008
  • 터널의 경우 타구조물에 비해 화재빈도가 상대적으로 높지는 않으나, 밀폐된 공간이라는 특성상 5분이내 1000도 이상으로 급격한 온도상승이 발생할 수 있으므로, 화재발생시 대형인명피해 및 화재 후 막대한 보수/보강비용이 파생된다. 이에 본 연구에서는 선진외국의 터널화재 시나리오를 준용하여 화재강도(ISO, MHC, RWS)에 따른 콘크리트 PC패널라이닝의 내부 전열특성 규명하였으며, 열손상 범위를 도출하기 위해서 ITA 기준을 적용하여 평가하였다. 연구결과 ISO화재조건에서는 30mm, MHC에서는 50mm, RWS에서는 100mm의 화재손상범위가 도출되었으며, 폭렬깊이는 RWS에서 30mm가 발생하는 것으로 나타났다. PC패널이 지보재의 역할을 할 경우엔 최소100mm깊이의 콘크리트 화재손상범위에 대한 내화성능확보방안이 적용되어야 하며, 비 지보재일 경우 PC패널라이닝의 두께를 100mm이상 확보하여야 한다.

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건축디자인과정에서 문제해결의 특성에 관한 연구 (A study on the characteristic of problem solving process in the architectural design process)

  • 김용일;한재수
    • 한국디지털건축인테리어학회논문집
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    • 제11권3호
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    • pp.53-59
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    • 2011
  • In creative design, it is necessary to understand the characteristic of architectural design. In the world of design problem, a distinction can be made between those that are well-defined and those that are ill-defined. Well-defined problems are those for which the ends or goal, are already prescribed and apparent, their solution requires the provision of appropriate means. For ill-defined problems, on the other hand, both the ends and the means of solution are unknown at the outset of the problem solving exercise, at least in their entirety. Most of design problems is ill-defined, which is unknown at the beginning of the problem solving exercise. In order to solve the design problem, Designers take advantage of the search methods of problem space, such as global-search-methods(depth-first-methods, breath-first-methods), local-search-methods(generate and test, heuristics, hill-climbing, reasoning) and visual thinking, which is represented through sketching. Sketching is a real part of design reasoning and it does so through a special kind of visual imagery. Also in the design problem solving it have been an important means of problem exploration and solution generation. By sketching, they represent images held in the mind as well as makes graphic images which help generate mental images of entity that is being designed. The search methods of problem space and a visual thinking have been crucially considered in the architectural design. The purpose of this paper is to explore the property of design by means of the pre-existed-experiment data and literature research. The findings will help design the architectural design for more creative results.

전산화 단층촬영을 이용한 한국 성인의 둔부 피하지방두께 측정 -근육주사 바늘길이 산정을 위한 기초조사- (Gluteal Subcutaneous Fat Thickness Measured by Computed Tomography as an Estimate of Proper Gluteal Intramuscular Injections in Korean Adults)

  • 주가을;송경애
    • 대한간호학회지
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    • 제40권2호
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    • pp.247-254
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    • 2010
  • Purpose: To study the thickness of gluteal subcutaneous fat (SCF) and propose an adequate length for needle for gluteal intramuscular injections based on computed tomography (CT) measurements. Methods: The thickness of gluteal SCF were measured and studied for 568 patients who visited a tertiary hospital in Seoul, Korea between January 2007 and February 2009 for routine health screening and who had abdominopelvic CT. Results: The average thickness of gluteal SCF was $15.92{\pm}4.08mm$ in males and $24.90{\pm}5.47mm$ in females. The thickness of gluteal SCF differed significantly according to gender. The gluteal SCF thickness was greater than 20.4 mm for 54 (12.3%) of the 440 male patients and 99 (77.3%) of the 128 female patients. Conclusion: The most common syringe needle used for gluteal intramuscular injections in Korea is a 23 G, 25.4 mm-needle. The SCF thickness must be less than 20.4 mm in order to reach the dorsogluteal muscles to a depth of at least 5 mm if this 25.4 mm needle is used. In many patients, especially in female patients, the 25.4 mm needles will result in improper intramuscular injections with the injection being into the SCF. Therefore an appropriate needle should be selected by considering the gender and SCF thickness of patients receiving gluteal intramuscular injections.

중학교 기술$\cdot$가정 교과서의 '자원의 관리와 환경' 영역과 다른 교과의 교육내용 관련성 분석 (Comparison between the Contents of 'Management of Resource and Environment' Area in Home Economics Textbook and Those of Other Subject Textbooks of Middle School)

  • 김지호;이연숙
    • 한국가정과교육학회지
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    • 제17권1호
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    • pp.55-68
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    • 2005
  • 본 연구는 제 7차 교육과정 기술$\cdot$가정 교과서 중 가정 부분의 '자원의 관리와 환경' 영역 내용과 다른 교과 내용을 분석하여 관련성을 파악하기 위하여 국어, 도덕, 사회, 수학, 과학, 기술, 체육, 음악, 미술 교과서를 분석하였다. 음악을 제외한 전 교과의 내용에서 '자원의 관리와 환경 영역의 내용과 유사한 내용이 발견되었다. 기술$\cdot$가정 교과서의 '자원의 관리와 환경' 영역과 사회교과의 3학년 내용과 많은 관련성을 보이고 있었다 가장 다른 교과와 관련성이 높은 '자원의 관리와 환경' 영역의 내용은 '자원의 활용과 환경' 중단원 중 환경 부분과 '우리들의 소비 생활' 중단원의 소비자 관련 내용으로 나타났다. 그리고 '청소년의 시간과 일 관리' 중단원의 내용이 다른 교과의 내용과 그 관련성이 가장 적게 나타났다. 각 교과마다 목표와 성격이 다르기 때문에 같은 주제라 할지라도, 다루고 있는 초점과 제시방법, 내용의 상세성 정도가 교과마다 차이를 보이 있었다.

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A simple estimate of the carbon budget for burned and unburned Pinus densiflora forests at Samcheok-si, South Korea

  • Lim, Seok-Hwa;Joo, Seung Jin;Yang, Keum-Chul
    • Journal of Ecology and Environment
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    • 제38권3호
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    • pp.281-291
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    • 2015
  • To clarify the effects of forest fire on the carbon budget of a forest ecosystem, this study compared the seasonal variation of soil respiration, net primary production and net ecosystem production (NEP) over the year in unburned and burned Pinus densiflora forest areas. The annual net carbon storage (i.e., NPP) was $5.75t\;C\;ha^{-1}$ in the unburned site and $2.14t\;C\;ha^{-1}$ in the burned site in 2012. The temperature sensitivity of soil respiration (i.e., $Q_{10}$ value) was higher in the unburned site than in the burned site. The annual soil respiration rate was estimated by the exponential regression equation with the soil temperatures continuously measured at the soil depth of 10 cm. The estimated annual soil respiration and heterotrophic respiration (HR) rates were 8.66 and $4.50t\;C\;ha^{-1}yr^{-1}$ in the unburned site and 4.08 and $2.12t\;C\;ha^{-1}yr^{-1}$ in the burned site, respectively. The estimated annual NEP in the unburned and burned forest areas was found to be 1.25 and $0.02t\;C\;ha^{-1}yr^{-1}$, respectively. Our results indicate that the differences of carbon budget and cycling between both study sites are considerably correlated with the losses of living plant biomass, insufficient nutrients and low organic materials in the forest soil due to severe damages caused by the forest fire. The burned Pinus densiflora forest area requires at least 50 years to attain the natural conditions of the forest ecosystem prior to the forest fire.

한국 성인형 치주염 환자의 치주낭 내 세균분포에 관한 암시야현미경적 연구 (Darkfield microscopic study of the bacterial morphotypes in the periodontal pockets of Korean adult periodontitis patients)

  • 박정민;남기윤;이인경;엄흥식;장범석
    • Journal of Periodontal and Implant Science
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    • 제33권2호
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    • pp.247-257
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    • 2003
  • The purpose of this study was to evaluate the difference of subgingival bacterial compositions between periodontally healthy and diseased sites. Subgingival plaque samples were obtained from 100 sites in 20 untreated adult periodontitis patients(experimental group), and 100 sites in healthy individuals(contro1 group). Before sampling, probing pocket depth(PPD) and clinical level of attachment(CAL), Plaque Index(PI), and Sulcus Bleeding Index(SBI) were recorded for each sampled sites. Microbial samples were collected from the bases of gingival sulci or periodontal pockets with sterile curettes. The samples were examined under darkfield microscope(${\times}$400). At least 150 bacteria were evaluated and categorized on the basis of bacterial morphology and motility, i.e. cocci, non-motile rods, motile rods, and spirochetes. In control group, subgingival microbial flora consisted of 73.7% of cocci, 20.0% of non-motile rods, 4.3% of motile rods, and 2.0% of spirochetes. The microbial samples from experimental group consisted of 51.5% of cocci, 19.4% of non-motile rods, 17.6% of motile rods, and 11.6% of spirochetes. The proportion of cocci was higher in control group than in experimental group. Proportions of motile rods and spirochetes were higher in experimental group than in control group. The proportion of nonmotile rods in experimental group and control group was not significantly different. Sulcus Bleeding Index and Plaque Index showed high correlation with the bacterial composition. These findings suggests that examination of subgingival bacterial proportion may serve as more sensitive mirror of the local periodontal status than clinical parameters.

전통복식 문화원형 콘텐츠의 디지털 활용 현황과 제언 (Digital Application and Suggestions of Cultural Prototypes in Traditional Costumes)

  • 조효숙;임현주
    • 복식
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    • 제60권6호
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    • pp.89-100
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    • 2010
  • This study is intended to analyze current status of costume in the cultural industry and explore feasibility of integrating costume as important cultural contents in the digital era. Among the websites for contents as the cultural archetypes, some have strong foundations while others don't. First, as for various archetypal characters restored based on the Korean history, most of their clothes focus on shapes and colors but lack details. They should be produced in 3D to provide back views or textile patterns to users. To ease understanding of the history of costume, user-friendly services such as launch of a pop-up window when users click on specific contents in question should be available for detailed information. At least there should be a link to other related sites where users can conveniently find more details. Second, some sites have too much data under one subject, increasing complexity and undermining orderliness. As a result, it takes long time to identify the site map. In this case, it is required to rearrange the contents with Quick View by subject and related links for in-depth study. Third, each subject is important to develop the archetypes for a variety of purposes. Creation of design derived from them or their commercialization can be an example but these activities should not restrict imagination of users or degrade the value of the archetypes. Last, it is needed to adopt validation system to detect the needs for a regular update (renewal) and to fix errors. We found many servers whose operation is not stable in general. When these technical issues are addressed for stable operation, users will rely on the sites to utilize them for their purpose of developing the cultural archetypes. In conclusion, advancement of www.culturecontent.com is essential. Based on efficient management and operation of the system, the quality of contents would be increased and multi-faceted advertising campaigns focusing on needs should be launched, to promote application of the contents. This is the recommendation for the future of the cultural archetype industry in Korea.

Constant Temperature Artificial Incubation of Spawned Eggs in Natural Nests from the Chinese Freshwater Soft-Shelled Turtle, Tryonyx sinensis Strauch(1862)

  • Oh, Young Nam;Kim, Sung Han
    • 한국발생생물학회지:발생과생식
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    • 제21권1호
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    • pp.101-110
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    • 2017
  • On June 14, 2008 (the first experiment) and July 24, 2008 (the second experiment), the shores of the Boseong River and the sandy beaches, Seokgok-myun, Moksadong-myun, Gokseong-gun in Jeollanam Province were investigated and a total of 29 soft-shelled turtle (Tryonyx sinensis) eggs in the natural spawning nest eggs were collected (13 eggs were collected in the first experiment and 16 eggs in the second experiment). The temperatures in the natural spawning nests were $25.9-36.9{\pm}0.5^{\circ}C$, the depth of the eggs was $5.2-7.5{\pm}0.5cm$ as the distance of the average $6.4{\pm}0.5cm$. 29 eggs were scattered at least 0.2 cm interval. Artificial incubation of 29 eggs was conducted in artificial nest boxes in thermo-plastic composition of the incubator, and then incubated at $26.5-35.5{\pm}0.5^{\circ}C$, and an average constant temperature was $31.2-32.1{\pm}1.0^{\circ}C$. The incubation days ranged from 53 to 55. In case of most turtles, incubation at $31^{\circ}C$ (higher temperatures) generally produces all or mostly females, while incubation at $25^{\circ}C$(cooler temperatures) produces all or mostly males. Exceptionally, in case of genus Trionyx, the sex ratio of female : male of T. sinensis of a freshwater soft-shelled turtle was approximately 1:1, which differs from other genera of turtles and makes T. sinensis Strauch only turtles presently known to lack temperature-dependent sex determination.

아스팔트 혼합물의 용적 특성을 이용한 소성변형 추정 연구 (Estimation of Rutting based on Volumetric Properties of Asphalt Mixture)

  • 이상범;도영수;김광우
    • 한국도로학회논문집
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    • 제6권3호
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    • pp.79-90
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    • 2004
  • 본 논문은 아스팔트 포장의 주요 파손 형태의 하나인 소성변형을 예측하기 위한 연구로서 빠르고 손쉽게 구할 수 있는 혼합물의 공극 관련된 물리적 특성인 공극률, 골재간극률 포화도 등에 근거하여 소성변형과의 상관성을 추정하고자 하였다. 이를 위하여 두 종류의 골재, 밀입도, 갭입도, 일반아스팔트, 개질아스팔트 등을 조합한 혼합물에 대하여 반복주행시험을 수행하였다. 그 결과 혼합물의 공극관련변수로 소성변형 깊이의 추정이 가능함을 확인하였다. 또한 국내에서 사용하지 않고 있는 물성이 골재간극률이 소성변형에 크게 영향을 미치는 인자로 확인되어 향후 국내 배합설계규정에 이 규정을 추가하는 것을 고려해야 할 것으로 사료되었으며, 포화도는 국내의 규정이 너무 높아 하향조정이 필요한 것으로 판단되었다.

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Clinical effect of calcium chelating and deproteinizing agent containing dental conditioning gel on alleviation of periimplant mucosa inflammation

  • Yang, Kwang-Heon;Lee, Jue-Yeon;Jung, Jin-Hyung;Shin, Hyun-Seung;Cho, In-Woo
    • 대한치과의사협회지
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    • 제53권9호
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    • pp.618-627
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    • 2015
  • Purpose : The purpose of this clinical study was to evaluate the effect of chelating and deproteinizing agent containing dental conditioning gel on alleviation of peri-implant mucosa inflammation. Methods: 36 patients with functionally loaded implants for at least 1 year and have clinical signs of peri-implant mucositis were recruited. At baseline, all implants received subgingival prophylaxis with ultrasonic scaler. In the test group, patients were provided a chelating and deproteinizing agent dental conditioning gel (Clinplant$^{(R)}$) and were given instructions to applicate it around the implants using an interdental brush for 2 weeks. Chlorhexidine and saline were provided to the positive control group and negative control group, respectively. The modified sulcus bleeding index (mSBI), modified plaque index (mPI), and probing pocket depth (PPD) were evaluated at baseline, 1 week, and 2 weeks. Results: In the Clinplant$^{(R)}$ and chlorhexidine group, mSBI (-0.81, -0.85 respectively; p<0.01), mPI (-0.46, -0.5 respectively; p<0.01), and PPD (-0.58, -0.48 respectively; p<0.01) at 2 weeks were significantly reduced from baseline. In the saline group, all the clinical parameters were reduced but there was no statistical significance. The saline may be attributed to the influence of prophylaxis at baseline. Conclusions: The present study demonstrated the beneficial clinical effects of chelating and deproteinizing agent containing dental conditioning gel to decrease peri-implant mucosa inflammation equivalent to chlorhexidine. This dental conditioning gel might be useful for alleviation of peri-implant mucosa inflammation.