• Proceedings of the Optical Society of Korea Conference
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• 2000.02a
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• pp.32-33
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• 2000

최근 디지털 정보 처리 기술의 획기적인 발전과 함께 저가의 반도체 레이저의 개발로 말미암아 광기록 장치(optical pickup device) 및 고속 광통신(optical fiber communication)분야에 응용을 위한 레이저 광학 시스템에 대한 연구가 활발하다. 광신호의 커플링(coupling) 및 스위칭(switching)을 기반으로 하는 이러한 광학 시스템은 일반적으로 광신호의 변조를 위한 광학 요소와 광학 요소의 공간적 제어를 위한 정밀 구동기로 구성되는데, 기존의 상용 시스템의 경우에는 독립적으로 기 제작된 광학 요소와 정밀 구동기를 사후에 조립하는 방법으로 소기의 목적을 달성하였다. 이와 같은 경우 제작에 많은 노력과 비용이 요구되며, 성능의 획기적인 향상을 기대하기 어려우므로 최근에는 Optical MEMS 혹은 MOEMS(Micro-Opto-Electro-Mechanical System)로 대변되는 마이크로머시닝기술(micromachining technology)을 이용한 초정밀 광학계의 제작 기술을 통하여 기존 시스템의 한계를 극복하고자 하는 노력이 다각도로 모색되고 있다. (중략)

• 한국게임학회지
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• v.6 no.1
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• pp.41-43
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• 2009

게임에서의 텍스트를 추출하고 이를 분석하고자 하였다. 기본적으로 그레마스의 구조생성기호학을 활용하여 텍스트를 분석하고자 하였는데, 연구방법론에서는 현상학, 해석에서는 정신분석학의 이론에서도 도움을 받았다. 구체적인 분석대상으로는 온라인게임인 스타크래프트, 리니지, 스페셜포스를 선택하였다. 연구문제는 이들 세 게임의 의미생성방식에 대한 탐구로 구성되었다. 각 게임의 의미생성방식은 구조생성기호학의 세 가지 층위에서 구분되어 연구되었다. 즉, 심층구조, 기호-설화구조, 담화구조의 세층위로 전환, 발화되면서 점진적으로 의미가 풍성해지는 과정이 탐구되었다. 각 게임의 차이, 나아가 게임 장르간의 차이는 주로 심층 수준의 차이에서 기인한다고 보인다. 이들 게임의 주요 공통점이자, 다른 매체와의 차이점은 행동자 모델에서 두드러지는데, 바로 이용자가 스스로 주체의 위치를 점하게 되는 것이다. 상호작용성으로 대변되는 게임의 특성은 이용자의 텍스트로의 적극적인 개입을 할 수 있게끔 한다. 이러한 적극적인 개입은 이용자가 스스로 텍스트의 주체가 되도록 허용하는데, 주체가 된다고 함은 곧 스스로의 욕망을 직접 대상에 투사하면서 텍스트를 창출함을 의미한다. 바로 이러한 점이 게임의 의미생성방식의 큰 특징이며 다른 매체들과의 주요한 차이점이기도 하다. 더불어 게임이 우리 문화와 사회에 커다란 영향을 미칠 수 있는 기제임이 입증되는 것이기도 하다.

• Journal of Korean Society of Steel Construction
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• v.19 no.6
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• pp.599-610
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• 2007

In this paper, we described a co-rotational formulation for the geometrical nonlinear analysis of three-dimensional frames. We suggested a new concept called the Zero-Twist-Section Condition (ZTSC) to decide the element coordinate system consistently. According to the ZTSC procedure, it is possible to obtain an element coordinate system and natural deformations consistently when finite displacements and rotations are induced in an element. Based on the developed procedure, numerical examples are investigated to calculate natural rotations while finite displacements are imposed on an element. Also, the developed co-rotational procedure gives accurate results in the analysis of post-buckling problems with finite rotations.

• Current Industrial and Technological Trends in Aerospace
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• v.4 no.1
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• pp.3-12
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• 2006

세계 항공기산업은 새로운 기술과 새로운 전략, 이른바 ‘차세대’라는 단어로 대변될 수 있는 다음세대를 위한 개발과 전략의 변화를 겪고 있다. 먼저 군용기의 경우 미국의 F-35가 첫 선을 보이면서 차세대 전투기의 새장을 열어가고 있으며 우리나라 역시 T-50/A-50, 한국형헬리콥터(KHP)개발, 조기경보기 도입 등 공군력 강화를 위한 준비들이 단계적으로 이루어지고 있어 그에 따른 산업발전이 기대되고 있다. 민간 항공기를 살펴보면 A-380과 같은 대형 항공기 개발 추세와 A320과 B737과 같은 Narrow-body 항공기 생산이 증가하는 양상을 보이고 있다. 또한 개인용 소형제트기(VLJ)와 같은 항공기들은 차세대 틈새시장(niche market)을 형성, 발전가능성을 열어가고 있다. 민간항공기의 향후 생산전망을 살펴보면, 대형여객기의 경우 2015년까지 총 7,900여대로 연평균 800여대의 생산이 이루질 전망이며 헬리콥터의 경우 연평균 1,870여대로 총 18,730여대의 헬리콥터가 생산될 전망으로 약 1,200억불의 시장을 형성할 것으로 전망되고 있다. 이렇듯 군용기 시장에서는 차세대의 첨단 항공기 개발과 양산이 가시화되고 있으며 민간항공기의 경우, 특정 세분시장(market segment)의 주도적 개발과 양산보다는 비즈니스 환경의 변화와 고객층의 다양화로 인해 각 시장의 고객 니즈(needs)에 부합되는 다양한 항공기 개발과 양산이 이루어질 것으로 보인다.

• Journal of The Korea Institute of Healthcare Architecture
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• v.24 no.2
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• pp.79-87
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• 2018

Purpose: The purpose of this paper is to provide logical basis on enlargement of toilet floor space for the disabled by "ACT ON GUARANTEE OF PROMOTION OF CONVENIENCE OF PERSONS WITH DISABILITIES, THE AGED, PREGNANT WOMEN. ETC" Revised Enforcement regulation [Asterisk 1] (2018.2.10.) and to help with making plans, designs and establishing policies by conducting experimental study with the enhanced floor area regulations. Methods: We conduct Experimental study, field work and interview for this paper. In experimental study, verification of the effective floor area was proceeded by measuring activity space for people in manual wheelchair, electric wheel chair and electric scooter and also reviewed useable area with the space expanded 0.2m both width and depth. In filed work, conducted an observation what other things (ex. sanitary equipment, hand rail and so on) can also affect the active space as well as effective floor space. In the interview, other problems and requirements that were not revealed were experimental study and observation of field work. Results : it's expected to provide better access to toilets for the disabled with the law revision of effective floor area. But, with the usage increasement of enlarged wheel chair and electric wheel chair, expanding side areas of toilet is also highly likely to be required going forward. Implications : Additional research is required on locations of exists and internal arrangement that effect the usage of toilet. It should be led to Universal design by making additional investigation and verification of the users patterns.

• Journal of the Korean Geotechnical Society
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• v.33 no.12
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• pp.93-105
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• 2017

This study presents direct shear tests, model tests, and numerical simulations to assess the effect of reduction of soil strength because of saturation during formation of ground cave-in caused by damaged sewer pipe lines. The direct shear test results show that the saturation affects the cohesion of soil significantly although it does not influence the friction angle of soil. To experimentally reproduce ground cave-in, the model tests were performed. As ground cave-ins were accompanied with extreme deformation, conventional finite element method has difficulty in simulating them. The present study relies on generalized interpolation material point method, which is one of meshless methods. Although there are differences between the model test and numerical simulation caused by boundary conditions, incomplete saturation, and exclusion of groundwater flow, similar ground deformation characteristics are observed both in the model test and numerical simulation.

• Journal of Radiation Protection and Research
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• v.31 no.3
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• pp.135-140
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• 2006

Intakes of radionuclides through both inhalation and ingestion pathways may occur particularly in an incident involving unsealed radionuclides. If one assume only one intake path in this case, which is usual in routine monitoring, a significant error in the evaluated committed effective dose($E_{50}$) may result. In order to demonstrate the potential errors, variations of the resulting committed effective doses were analyzed for different fractions of the inhaled activities to the total intake of $^{241}Am$. Simulated bioassav measurements for the lungs, urine and feces were generated based on the biokinetic model and data of the radionuclide, 5 ${\mu}m$ AMAD and absorption type M for inhalation, for various inhalation fractions. The potential errors in $E_{50}$ due to the assumption of one intake path were in the range from -100% to as large as +34,000% when the bioassays were made 3 days after the intakes. Larger errors are expected when only the feces assay is applied while inhalation intake exists. A strategy which employs two types of bioassay was proposed to reduce the error caused by a misjudgement of the intake path.

• Journal of The Korea Institute of Healthcare Architecture
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• v.26 no.1
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• pp.17-27
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• 2020

Purpose: The purpose of this study is to identify the difference in toilet approach way by wheelchair users according to the direction of the door and to suggest the layout of the toilet rooms most accessible to the wheelchair users. Methods: Survey to wheelchair users about approach to toilet have been conducted for the data collection. 90 answers have been analyzed statistically by SPSS 19.0 program. Results: The conclusions of this study are as follows. Firstly, spinal cord disorders prefer diagonal approach and lateral approach to the toilet, but brain lesions prefer diagonal approach and frontal approach to toilet. Secondly, the manual wheelchair users prefer the diagonal approach and the lateral approach to the toilet, and the electric wheelchair users has a different approach way to the toillet depending on the direction of the door. Finally, the layout of accessible toilets have to be designed for the diagonal approach to toilet, which is most preferred by wheelchair users. Implications: The toilet approach varies according to the disability types and the wheelchair types. Therefore, the size of accessible toilets should be larger than now considering the access of variety wheelchair users.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.5
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• pp.894-899
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• 2001

Intakes and excretions of zinc and copper were determined for 8 female adolescents (aged 16.4$\pm$0.5 y; body mass index 20.4$\pm$1.3kg/$m^2$; body fat 33.3$\pm$2.5%; bone mineral density of lumbar spine in L2-L4; 0.96$\pm$0.08g/$\textrm{cm}^2$) when they consumed diets basal and high in calcium for 6 days each. All subjects consumed a basal Ca diet containing 800 mg, Korean RDA level of the subjects, and a high Ca diet containing 1200mg, RDA plus 2 SDs of calcium intake. The diets provided 58% of energy intake as carbohydrate, 25% as fat, and 17% as protein. Food, urine and fecal samples were collected during the last 3 days of each feeding period and were assayed. Mean daily intakes on the basal and high calcium diets, respectively, were 6.57 and 6.37 mg for zinc and 910 and 812 $\mu\textrm{g}$for copper. Fecal excretion of copper and zinc in relation to intake was significantly greater on the high calcium than on the basal calcium diet. Hence, apparent absorption rate was significantly lowered from 98.7% on the basal calcium diet to 97.9% on the high calcium diet for zinc from 66.3% to 56.4% for copper, respectively. Urinary loss of copper was not detectable but that of zinc was 0.38mg on the basal diet and 0.47mg on the high calcium diet. Copper retention was 899$\pm$105$\mu\textrm{g}$/day on the basal calcium diet and 792$\pm$20.8$\mu\textrm{g}$/day on the high calcium diet, and zinc retention was 3.95$\pm$0.91mg/day and 3.11$\pm$0.89mg/day. Thus, copper and zinc retention was significantly decreased on the high calcium diet (p<0.05). Summarizing the results, apparent absorption and retention of zinc and copper were significantly decreased by calcium supplementation. Therefore, it is suggested that interactions among minerals should be considered in determining RDA.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.5 no.2
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• pp.143-149
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• 2002

Purpose: The following study was performed to reveal the relationship between Clostridium difficile colitis in childhood and associated antibiotics. Methods: From January 2000 to June 2002 at Seoul National University Children's Hospital, 85 symptomatic pediatric patients who showed positive stool culture for Clostridium difficile were included. The implicated antibiotics within 2 months before stool culture were analyzed. Of the 85 patients, there were 50 males and 35 females, and their average age was 2.5 years. Results: There was a history of implicated antibiotics within 2 months in 55 cases (67%). Forty-three patients (78%) of them showed Clostridium difficile in stool culture during antibiotics treatment. The time interval between the initiation of antibiotics and stool culture ranged from one day to 7 weeks (mean 10 days) in these patients. In the remaining 12 patients, Clostridium difficile was detected after the discontinuation of antibiotics. The time interval between the discontinuation and stool culture ranged from one day to 7 weeks (mean 12 days). The associated antibiotics were cefotaxime (20 cases), amikacin(15 cases), ampicillin (13 cases), cefazolin (8 cases), vancomycin (8 cases), etc. In 31 cases, more than one antibiotics were prescribed. Conclusion: When diarrhea occurred in young children during antibiotic usage or with a past history of recent antibiotic usage, Clostridium difficile should be investigated as a cause of diarrhea for proper management.