• 대한물리의학회지
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• 제11권3호
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• pp.41-47
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• 2016

PURPOSE: Forward head posture (FHP) is one of the most common postural problems among white-collar workers who perform highly repetitive tasks in the same position. The aim of this study was to research the effects of thoracic and lumbar support fixtures on forward head posture (FHP) during visual display terminal (VDT) work. METHODS: The subjects were 36 healthy male students with no problems in their medical history or respiratory systems. The subjects were randomly assigned to three groups: control group (n=12), thoracic support fixtures (n=12), and lumbar support fixtures (n=12). We conducted a text typing task of the same content for 20 minutes, and evaluated the angles, including the craniovertebra angle (CVA), craniorotation angle (CRA) with photogrammetry. RESULTS: The thoracic and lumbar support fixture groups showed a statistically significant difference at the CVA and CRA to the control group (p<.05), and the post-hoc test showed an increase of the CVA and decrease of the CRA than the control group. However, when we compared the effects of thoracic and lumbar support fixtures on FHP, there was no significant difference in the difference in decrease of the CVA or increase of the CRA (p>.05). CONCLUSION: We determined that VDT work using thoracic and lumbar support fixtures has a positive effect on forward head posture in white-collar workers. Further studies are required to find the more effective location of support fixtures.

• 한국CDE학회논문집
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• 제20권4호
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• pp.348-356
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• 2015

It is important to devise methods for assisting dentists to consistently determine implant positions and directions and to accurately perform drilling tasks during dental implant surgery. In this paper, we propose a novel approach to tooth implant placement planning which deals with the determination of the positions and directions of multiple implant fixtures for a set of missing mandibular teeth and suggests the selection of the sizes and types of the implant fixtures. We combine Korean standard data in the sizes and positions of human teeth with the patient specific 3D models of mandibular jawbones, nerve curves, and neighboring teeth around the missing teeth in order to determine the positions and directions of the implant fixtures for the missing teeth. Using the geometric and spatial information of the jawbones, the teeth and the implant fixtures, we can construct the 3D models of surgical guide stents which are crucial to perform drilling tasks with ease and accuracy. Adopted in 3D simulation of dental implant placement, the approach can provide surgeon students with good educational contents. We also expect that, with further work, the approach can be used as a useful tool to plan for dental implant surgery.

• 한국화재소방학회논문지
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• 제24권5호
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• pp.136-141
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• 2010

본 연구에서는 옥내 조명 설비의 전원을 ON/OFF 하기 위해 사용되는 저압용 스위치의 구조 및 발열 메커니즘을 제시하고, 에너지원의 종류에 따라 스위치의 고정금구 및 가동 접점 등의 소손패턴을 제시함으로써 향후 예상되는 PL 분쟁의 판단 근거를 확보하는데 있다. 스위치에 인가된 일반 화염은 한국산업규격(KS)의 난연성 시험 방법을 적용하였다. 또한 스위치에 공급된 전류는 대전류공급장치(PCITS)를 이용하였다. 실험이 진행될 때 주위의 온도는 $22{\pm}2^{\circ}C$, 습도는 40~60%를 유지시켰다. 스위치의 발열은 배선과 클립의 접속 불량, 가동 접점의 절연 열화 및 접촉 불량 등에 의해서 생성되는 것으로 판단된다. 일반 화염에 의해 소손된 스위치는 표면이 균일하게 탄화되었으며, 화원을 제거하면 자연 소화되었다. 일반화염에 의해 탄화된 스위치를 분해한 결과 고정금구 및 가동 접점 등은 비교적 양호한 형태를 보였으나 외함, 클립 지지대, 가동 접점, 표시램프 등에서 탄화 및 변색을 확인할 수 있었다. 과전류에 의해 소손된 스위치는 배선을 연결하는 클립 및 클립 지지대 등은 소손의 흔적이 거의 없으나 고정금구, 가동 접점, 표시 램프 등은 심하게 탄화되었다. 즉 접촉 저항이 큰 부분에서 집중적으로 소손되었고 내부에서 외부로 탄화가 진행되는 패턴을 나타냈다. 따라서 소손된 스위치의 탄화 패턴 및 금속 금구류의 특성을 분석하면 최초의 에너지원 판정이 가능하다.

• 대한심미치과학회지
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• 제8권1호
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• pp.46-59
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• 1999

A fixed bridge is preferred as a prosthetic option supported by oral implants. However, it is very difficult to re tore edentulous maxilla with fixed prosthesis in cases with improper position and angulation of fixtures, abnormal jaw relation, and need for proper lip support. Six Br${\aa}$nemark implants were installed in edentulous maxilla opposing mandible with natural dentition. A removable hybrid prosthesis attached to a bar milled by 6 degrees was therefore designed to overcome such disadvantages of fixed prosthesis. Lateral stabilization of removable prosthesis was obtained by framework closely fitting the milled bar. Support for the prosthesis was ensured by three elevated areas on the bar. Two precision attachments(CEKA REVAX) provided appropriate direct and indirect retention without influencing support. A clinical and laboratory procedure was presented.

• 한국정밀공학회지
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• 제18권1호
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• pp.98-103
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• 2001

Machining is the commonly used process in the manufacturing of prototypes. This process offers several advantages, such as rigidity of the machine, precision of the machine, precision of the operation and specially a quick delivery. The weight and immobility of the machine support and immobilize the part during the operation. However, despite these advantages it shows, machining still presents several limitations. The immobilization, location and support of the part are referred to as fixturing or workholding and present the biggest challenge for time efficient machining. So it is important to select and design the appropriate fixturing assembly. This assembly depends on the complexity of the part and the tool paths and may require the construction of dedicated fixtures. With traditional techniques, the range of fixturable shapes is limited and the identification of suitable fixtures in a given setup involves complex reasoning. To solve this limitation and to apply the automation, this paper presents the Reference Free Part Encapsulation(RFPE) and implementation of the encapsulation system. The feature-based modeling system and the encapsulation system are implemented. The small part of which it is difficult to find out the appropriate fixturing assembly is made by this system.

• 대한가정학회지
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• 제39권6호
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• pp.109-122
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• 2001

This study was performed to identify the roles of residents for the environmentally sound and sustainable development, taco-polis(kologisches Bauen), eco-village and Symbiotic Housing. These buildings will achieve energy efficiency through design strategies such as passive solar heating system, natural cooling and day lighting. Their infrastructure will feature parking on the periphery, extensive pedestrian paths, outdoor ground lights that preserve stellar visibility, and environmentally sensitive technologies such as low writer use fixtures. And they will restore biodiversity while protecting the wildlife, wetlands, forests, soil, air and water. Their houses wile be designed to support home-based occupations, offering high-speed Internet access and other options to promote a localized, sustainable economy. To support and encourage the evolution of sustainable settlements, it is necessary to prepare constructing the physical facilities and the social functions relating with residents. The roles of residents are important to provide a high Quality lifestyle and to integrate a supportive social environment with a low-impact way of life. This study concluded the four main roles of residents for the sustainable of Eco-polis and Ecovillage. 1. Residents assist transition towards a sustainable society as eco-conscious consumers in the planning stage. 2. Residents live in a ecological way for the sustainable ecovillage. 3. Residents exchange information and education for increasing the community glue as a communication network. 4. Residents support and transmit their cultural vitality and tradition for the next generation. So, users are expected to encourage resident's participation in the planning, design, ongoing management and maintenance of the sustainable ecovillage.

• 대한치과보철학회지
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• 제29권1호
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• pp.167-213
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• 1991

The successful replacement of missing teeth has been one driving aim behind the emergence of implant dentistry as both a technology and clinical vocation for over four decades. To date, a multitude of dental implant devices had been designed and utilized in the patient population. Most of these devices have been designed without support of the engineering criteria. The long-term success of any dental implant is dependent upon the optimization of stresses which occurs during oral function and parafunction. Although many studies have examined the biologic interactions between dental implants and living tissue, few studies have been reported on the biomechanical aspects of dental implants. The purpose of this study was to analyze the stress distribution of osseointegrated prosthesis on certain conditions, such as amount of load, location of load, length of fixtures, number of fixtures used, arch shape, bone quality, etc. Three dimentional finite element analysis was used for this study. FEM models were created using commercial software(Super SAP. for IBM 16 bit AT computer. All elements were 8-node brick, isoparametric. Mandible and prosthesis was modeled with 780 elements and 1074 nodes. The results were as follows : 1. In case of cantilever extension, there was a compressive stress at the base of the first implant and a tensile stress at the base of the second implant. 2. The stresses were linearly proportional to the amount of load. 3. The stresses were linearly proportional to the length of cantilever. 4. There was a stress concentration at the neck of the implant and bone under horizontal loads.

• 한국주거학회:학술대회논문집
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• 한국주거학회 2000년도 학술발표대회논문집
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• pp.123-129
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• 2000

The purpose of this study was to provide the fundamental data for the effective housing remodeling plan. Through the questionnaire survey, the actual conditions of remodeling in apartment housing were investigated. And as the result of statistic analysis, the relationships between characteristics of remodeling and building life-cycle, and family life-stage, were found out. The major findings of this study are as follows; 1) Most of apartment residents have remodeled the family living space and private living space. In detail, they performed remodeling frequently the change of finishing materials, facilities and equipments, and the change of the location of curtain wall ＆ storage fixtures. 2) It might be predicted that the building life-cycle was influential variable to predict apartment residents' remodeling. Therefore, in planning the support service for the remodeling, the building life-cycle should be taken into consideration.

• Management Science and Financial Engineering
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• 제10권2호
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• pp.73-87
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• 2004

Automotive and aircraft assembly process rely on fixtures to support and coordinate parts and subassemblies. Fixture layout in multi-station panel assemblies has a direct dimensional effect on final products and thus presents a quality problem. This paper describes a methodology for fixture layout design in multi -station assembly processes. An optimal fixture layout improves the robustness of a fixture system against environmental noises, reduces product variability, and eventually leads to manufacturing cost reduction. One of the difficulties raised by multi-station fixture layout design is the overwhelmingly large number of design alternatives. This makes it difficult to find a global optimality and, if an inefficient algorithm is used, may require prohibitive computing time. In this paper, simulated annealing is adopted and appropriate parameters are selected to find good fixture layouts. A four-station assembly process for a sport utility vehicle (SUV) side frame is used throughout the paper to illustrate the efficiency and effectiveness of this methodology.

• 한국농촌건축학회논문집
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• 제17권4호
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• pp.57-65
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• 2015

In contrast to apartments, detached houses offer the possibility of more than one entrance connecting interior and exterior spaces. This study examines the location, function, and use of second doors in detached houses in rural areas. The study employs survey and interviews conducted in 2015, focusing on 18 detached houses among 40 houses previously surveyed in 1995. In 1995, 21 second doors were found, while in 2015, 19 were found. The study led to the following conclusions. First, most houses did have second doors installed by 1995 or 2015. Second doors tended to be installed in kitchen and utility rooms. The function of second doors was most closely connected to the kitchen because utility rooms were placed adjacent to kitchens. Secondly, changes in the use and number of second doors were changes in family life cycle and composition, the need for new equipment facilities, the use of new architectural materials, and the installation of new second doors for extension of space. Finally, exterior spaces accessed by second doors tend to be a meeting of semi-interior or semi-exterior space and exterior space only. Those spaces tended to be designed for kitchen fixtures or to support kitchen activities.