• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2018년도 춘계학술대회
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• pp.371-373
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• 2018

자전거 등하교 및 출퇴근족의 안전을 위하여 방향 표시등의 기능은 반드시 필요하다. 본 연구에서는 아두이노를 활용하여 조립식 자전거에 방향 표시등 기능을 개발하였다. 아두이노의 간단한 기능을 통해 핸들에 스위치를 부착하여 방향 표시등을 켜고 끄게 할 수 있다. 또한 간단한 기능이므로 자전거를 가지고 있는 사람들이 스스로 DIY를 하여 제작할 수 있는 메이커 활동으로 적합하다고 판단된다. 본 논문에서 제안된 기능을 통하여 자전거에 필요한 서비스를 많이 부착할 수 있는 가능성을 열어두었다.

• 대한치과보철학회지
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• 제32권2호
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• pp.225-233
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• 1994

The restorations of the severely damaged teeth by post core have been increased with the developement of endodontic procedures. But high failure rates of these procedures being reported, various restorative modifications were induced for successful treatments. Cast post-core and prefabricated post with core buildups are choice of treatment. The main causes of failure of the restorations are the fracture of post and core, root fracture, and recurrent caries due to microleakage. Recently, the acid etching technique and the use of dentin bonding agent at tooth surface to reduce the possible microleakage at the tooth-restoration interfaces were introduced. The object of this study was to measure and compare the microleakage by the types and cementation methods of post-core. For this study, forty extracted human anterior teeth were selected for specimen. After cleansing and routine endodontic procedures, anatomic crowns of each specimen were removed at the level of 2mm above the cementoenamel junction. Canals were preparated for post insertion and specimens were divided into four groups randomly. Post-cores were fabricated according to method for each group. Microleakage was measured by length of dye penetration at the tooth-restoration interfaces with measuring microscope at 50 magnification. Oneway ANOVA and t-test were performed for statistical analysis of resulting data. The following results were obtained from this study. 1. There wert significant statistical differences in degree of microleakage between each group (p<0.01). 2. Cast post-core cemented with ZPC (Group I) showed the most severe microleakage pattern$(1.5547{\pm}0.0872mm)$, and cast post-core cemented with adhesive resin cement after tooth surface treatment with dentin bonding agent (Group II) showed the least microleakage $(0.1497{\pm}0.0872mm)$. 3. Group IV revealed less dye penetrations than group III, but no statistical significance was seen between two groups.

• 건축역사연구
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• 제7권4호
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• pp.61-75
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• 1998

The Unite d'Habitation at Marseilles was an experimental project that Le Corbusier had been waiting for since 1920s in order to explore his ideals and visions in mass housing and city planning. As a leader of the first generation members in CIAM, Le Corbusier tried to give a new form and an order to the Unite d'Habitation at Marseilles in both building design and city planning level. The purpose of this research is to investigate the design characteristics of the Unite d'Habitation at Marseilles in three different levels of built environment with a particular emphasis on the process through which an original form is derived from its contextual settings. In the level of city planning, Le Corbusier aimed to reshape traditional low-rise urban housing by deploying several Unites spaciously. Le Corbusier believed that the spacious deployment of Unites would bring us both the functional economy in the city and the natural amenity in the suburbs. As Unite d'Habitation would be called frequently as vertical garden city, the influence of suburban garden city on Unite d'Habitation is apparent. In the building level, the binomial harmony of individual-collectivity was pursued by providing three different public floors and by combining 23 different family unit types in the Unite d'Habitation at Marseilles. In order to visualize the concept of object-type, family units were prefabricated and inserted into the structural frame of the Unite d'Habitation at Marseilles. Two family units are combined to make a three-story section with street corridor in the middle. This three-story section unit is very original as it has access corridor every third floor and each unit could have considerable depth with the help of the living space of two story height. In consideration of formal and plan similarity as well as contextual edivdence, it is concluded that the three-story section of the Unite d'Habitation is derived more from Narkomfin Apartments than from the monastery at Ema or Immuble Villas.

• 디지털융복합연구
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• 제18권11호
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• pp.207-214
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• 2020

본 연구는 다양한 환경에서 임시 주거를 위한 공간을 쉽게 구성하는 방법을 분석한다. 이를 위해 모듈라 조립식 건축 구조의 사례를 분석하고 임시 주거 공간을 형성할 수 있는 다양한 해결 방안을 탐색한다. 본 연구를 통해 예측이 불가능한 다양한 상황에서 사용자의 안정적 생활 환경을 위한 주거 공간을 구축하기 위해 다양한 방법을 제안하고자 한다. 이와 관련된 다양한 해외의 특허 사례를 수집하고 분석하여 다음과 같이 총 4가지의 그룹으로 그 결과를 도출하였다. 이는 1) 소규모 부품을 활용한 조립 방식, 2) 프리패브 모듈의 적층 방식, 3) 공간 확장 방식, 그리고 4) 세부요소의 제작 방식으로 구분될 수 있으며, 이를 기반으로 향후 보다 더 저비용 및 효율적으로 구축이 가능한 프리패브 임시 주거 공간의 구조를 연구하고자 한다.

• 한국전산구조공학회논문집
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• 제24권5호
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• pp.513-520
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• 2011

본 연구에서는 스트라치 시스템의 긴장설치과정 해석을 수행하기 위한 개선된 명시적 해석법을 제안하였다. 스트라치 시스템은 Stressed-Arch에서 유래한 용어로 슬리브에 의한 갭이 도입된 유동 하현재가 내부의 긴장재에 의한 초기장력의 도입으로 서서히 닫히게 되고, 이에 따라 전체 구조물이 상승하여 최종적인 아치형태의 구조물을 형성하는 독창적인 구조시스템이다. 스트라치 시스템의 초기장력 도입과정을 긴장설치(stress-erection process) 과정이라 하며, 초기곡률의 도입에 따라 유동 상현재에는 과도한 초기변형이 발생하여 소성거동에 의한 강체회전이 발생하는 불안정 구조물이 된다. 본 연구에서는 이러한 스트라치 시스템의 불안정 거동특성을 해석하기 위해서 소성힌지가 적용된 보-기둥요소를 사용하여 유동상현재를 모델링하였고, 불안정 구조물의 해석법에 효과적으로 사용되는 동적이완법의 개선된 알고리즘을 개선하여, 실제 스트라치 구조물의 긴장설치과정 해석을 수행하였으며, 실제 프로젝트에 대한 해석결과의 분석을 통하여 제안된 해석법의 적용성을 검증하였다.

• The Journal of Advanced Prosthodontics
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• 제3권2호
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• pp.90-95
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• 2011

PURPOSE. To compare the fracture resistance and the mode of failure of endodontically treated teeth restored with different post-core systems. MATERIALS AND METHODS. Root canal treatment was performed on 40 maxillary incisors and the samples were divided into four groups of 10 each. For three experimental groups post space preparation was done and teeth were restored with cast post-core (Group B), stainless steel post with composite core (Group C) and glass fiber post with composite core using adhesive resin cement (Group D). Control group (A) samples were selected with intact coronal structure. All the samples were prepared for ideal abutment preparation. All the samples were subjected to a load of 0.5 mm/min at $130^{circ}$.until fracture occurred using the universal testing machine. The fracture resistance was measured and the data were analyzed statistically. The fracture above the embedded resin was considered to be favorable and the fracture below the level was considered as unfavorable. The statistical analysis of fracture resistance between different groups was carried out with t-test. For the mode of failure the statistical analysis was carried out by Kruskal-Wallis test and Chi-Square test. RESULTS. For experimental group Vs control group the fracture resistance values showed significant differences (P<.05). For the mode of failure the chi-square value is 16.1610, which means highly significant (P=.0009) statistically. CONCLUSION. Endodontically treated teeth without post core system showed the least fracture resistance demonstrating the need to reinforce the tooth. Stainless steel post with composite core showed the highest fracture resistance among all the experimental groups. Teeth restored with the Glass fiber post showed the most favorable fractures making them more amenable to the re-treatment.

• 대한치과보철학회지
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• 제46권3호
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• pp.280-289
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• 2008

STATEMENT OF THE PROBLEM: Recent data regarding the effects the cement type and abutment heights on the retentive force of a prosthetic crown are inconsistent and unable to suggest clinical guidelines. PURPOSE OF THE STUDY: This study evaluated the effects of different types of temporary cements and abutment heights on the retentive strength of cement-retained implant-supported prostheses. MATERIALS AND METHODS: Prefabricated implant abutments, 4 mm in diameter, $8^{\circ}$taper per side, and light chamfer margins, were used. The abutment heights of the implants were 4 mm, 5.5 mm and 7 mm. Seven specimens of a single crown similar to a first premolar were fabricated. Six commercially available temporary cements, TempBond, TempBond NE, Cavitec, Procem, Dycal, and IRM, were used in this study. Twenty-four hours after cementation, the retentive strengths were measured using a universal testing machine with a crosshead speed of 0.5 mm/min. The cementation procedures were repeated 3 times. The data was analyzed using two-way analysis of variance and a Tukey test (${\alpha}$=0.05). RESULTS: The tensile bond strength ranged from 1.76 kg to 19.98 kg. The lowest tensile strengths were similar in the TempBond and Cavitec agents. Dycal showed the highest tensile bond strength (P<0.01). More force was required to remove the crowns cemented to the long abutments (P<0.05). CONCLUSION: TempBond and Cavitec agents showed the lowest mean tensile bond strength. The Dycal agent showed more than double the tensile bond strength of the TempBond agent.

• 한국공간구조학회:학술대회논문집
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• 한국공간구조학회 2008년도 춘계 학술발표회 논문집
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• pp.49-52
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• 2008

목재자원을 효율적으로 활용하기 위한 목적으로 개발된 공학목재는 기존에 구조용으로 사용되어 오던 목재제품에 비해 강도가 높으면서도 안정적인 장점을 가지고 있다. 또한 설계 상세에 따라 부재를 주문 제작이 가능하며, 대규모 건축물에도 주요 구조체로 사용되어져 오고 있다. 장 스팬이 요구되는 재료로 구조용 집성재나 목재 I형장선, 단판적층재(LVL) 등을 활용하여 사용되고 있다. 본 프로젝트는 공학목재 중에서 집성재 및 막재를 이용한 구조 시스템으로, 강원도 뿌리기념관 공원공사 중 "야외무대 지붕공사"로 구조 재료, 구조설계 및 시공에 관한 내용으로 구성되어 있다. 지붕 구조재는 PVF/PFLT(테드라 필름코팅) 소재의 막이 사용되었다. 기둥 및 경사 부재는 강재(SS400)를 사용하였고, 캔틸레버 보 부재는 비대칭 구성 집성재(10S-28B)를 이용하였다.

• 콘크리트학회논문집
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• 제28권2호
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• pp.129-139
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• 2016

대형 PC기둥의 양중부하를 줄이고 접합부의 구조일체성을 개선하기 위한 대안으로서, 중공 PC기둥이 사용될 수 있다. 본 연구에서는 PC부의 생산성과 구조일체성을 개선한 새로운 중공 PC기둥을 개발하였다. PC부를 제작하기 위하여 구조용 골형플레이트를 내부영구거푸집과 수평 관통철근을 사용하였다. 제안된 PC기둥의 내진성능을 검증하기 위하여, 1/2 스케일의 기둥 실험체 4개에 대하여 일정 축력에서 반복 횡가력실험을 수행하였다. 실험 변수로는 횡철근 간격, 강섬유 사용여부, 그리고 PC부의 두께가 고려되었다. 실험 결과, 제안된 PC기둥은 외곽 PC부의 취성적인 파괴 없이 우수한 하중재하능력과 변형능력을 보이는 것으로 나타났다. PC부에 횡철근을 촘촘히 배근하거나 강섬유를 사용할 경우, PC 콘크리트의 탈락을 제한하여 변형능력을 증가시킬 수 있었다.

• KIEAE Journal
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• 제16권6호
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• pp.103-108
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• 2016

Purpose: This study has developed economical and environmentally friendly storage type infiltration facilities that securing storage space inside the infiltration facility. It focused on preventing flooding rainfall as well as securing more groundwater through rainwater infiltration that is valuable for the dry season. In addition, this study compares the installation cost of the storage-type infiltration facility to the cost of the conventional rainwater management facilities to demonstrate the economic efficiency of the storage-based infiltration facility. Method: Unit infiltration of this facility is calculated and when it was applied to a certain capacity, the amount of countermeasures are proposed in case study. Result: Unit infiltration of it is $0.2541m^3/hr$ and un it Temporary storage of it is $1.054m^3/m$. As a result, the infiltration effect of this facility is $1.306m^3/hr$. The cost was approximately 30% reduction in time to apply the storage type infiltration facility as compared with the case to apply the existing penetration of the facilities. Since the penetration of the existing facilities is smaller than that and it has much securing volume to process the same the amount of countermeasures. Therefore, it is determined that the cost significantly increases in material cost part. On the other hand, storage type infiltration facility is installed a small quantity because Unit Temporary storage and infiltration are bigger than that. So, it occurred to reduce material and installation costs.