• 산업경영시스템학회지
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• 제21권47호
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• pp.181-191
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• 1998

Bevel gears are suitable for transmitting power between shafts at practically any angle or speed. However, the particular type of gear best suited for a specific application is depends upon the mountings, available space, and operating conditions. Therefore it is important in any general design imploying gears to first make a study of all the conditions under which the gear must operate. Presented in this paper is a S/W calculating design parameters automatically for bevel gears. This S/W provides the Standards for the design of straight bevel, zerol bevel, spiral bevel and hypoid gears. Topics include preliminary design parameters, blank design including standard taper, uniform depth, duplex taper and tilted root so that Gleason, Klingelnberg and Oerlikon machine tools are covered.

• Macromolecular Research
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• 제10권1호
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• pp.44-48
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• 2002

The supermolecular structures of poly(ethylene terephthalate) (PET), poly(ethylene 2,6-naphthalate) (PEN), and their blend were investigated with optical microscopy and small angle light scattering. With increasing the crystallization temperature, incomplete spherulitic texture was developed for the PET samples. At a high crystallization temperature of 220 $^{\circ}C$, the light scattering pattern represented a random collection of uncorrelated lamellae. The general morphological appearances for the PEN samples were similar to that of the PET. A notable feature was that the spherulites of the PEN formed at 200 $^{\circ}C$ showed regular concentric bands arising from a regular twist in the radiating lamellae. The spherulitic morphology of the PET/PEN blend was largely influenced by the changes of the sequence distribution in polymer chains determined by the level of transesterifcation. The increased sequential irregularity in the polymer chains via transesterification caused a morphological transition from a regular folded crystallite to a tilted lamellar crystallite.

• 한국태양에너지학회 논문집
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• 제29권3호
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• pp.59-65
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• 2009

In this paper, to find effective way of the production of the distilled water with solar radiation, 4 different boxes of condensation systems were compared. The bottom size of boxes are identical but the angles of top collecting plates are different. During the solar radiation, condensation did not occur and the condensation start when solar radiation was decreased. The maximum condensation reached when the temperatures of the top and bottom parts are equal. The condensation was continued until sunrise with gradually reduced amount. When top plate angle was $45^{\circ}$, condensation was highest compared with the other angles.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2008년도 하계학술대회 논문집 Vol.9
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• pp.437-438
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• 2008

The Conventional patterned vertical alignment (PVA) device shows a very high contrast ratio at normal direction and does not require rubbing process. However it has a disclination area in which the liquid crystal can be collision in the boundary domain region. In this paper, we studied PVA(Z-shape) device in which the liquid crystal can be tilted down in multiple directions stably because the surface pretilt angle is controlled by photopolymerization of the UV - curable reactive mesogen (RM) under a proper condition. Consequently, the device shows improved electro optical properties as compared to conventional PVA mode.

• 제어로봇시스템학회논문지
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• 제18권2호
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• pp.110-117
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• 2012

This paper describes a new design of optical flow estimation system with three cameras. Optical flow provides useful information of camera movement; however a unique solution is not usually available for unknowns including the depth information. A camera and two tilted cameras are used to have different view of angle and direction of movement to the camera axis. Geometric analysis is performed for cases of several independent movements. The ideas of taking advantage of the extra information for robot navigation are discussed with experimental results.

• Bulletin of the Korean Chemical Society
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• 제15권5호
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• pp.369-374
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• 1994

Self-assembled (SA) and Langmuir-Blodgett (LB) monolayers of arachidic acid on silver surfaces have been investigated by a reflection-absorption Fourier transform infrared spectroscopy. Arachidic acid was adsorbed on silver as carboxylate with its two oxygen atoms bound symmetrically to the surface. Although both the SA and LB monolayers consisted of fully extended trans zigzag carbon chains, a closer examination indicated that the SA monotayers should possess a more ordered crystalline structure than the LB monolayers. The infrared spectral data dictated that the extent of methyl group exposure at the air-film interface was greater in the SA monolayers than the LB monolayers, in agreement with the contact angle measurement. From a theoretical analysis, the alkyl chains in each monolayers seemed to be tilted away from the surface normal by less than $3.5^{\circ}$, but in opposite directions. Arachidic acid monolayers were concluded to have same structure as stearic acid monolayers.

• International Journal of Air-Conditioning and Refrigeration
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• 제17권4호
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• pp.123-128
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• 2009

In this paper, effective ways to produce distilled water with solar radiation was investigated. Four different boxes of condensation systems were compared. The bottoms of the boxes were identical, but the angles of the top collecting plates were different. During the solar radiation, condensation did not occur. Condensation started when solar radiation was decreased. The maximum condensation was found when the temperatures of the top and bottom parts were equal. The condensation was continued until sunrise with gradually reduced rate. When the collecting plate angle was $45^{\circ}$, condensation was the highest compared with other angles.

• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2010년도 춘계학술발표대회
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• pp.417-420
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• 2010

반도체 패키지 제조공정 중에는 제품에 일련번호를 인쇄하는 마킹공정이 있다. 마킹 공정에서 새겨진 문자는 해당 관리기준에 따라 관리되고 있는데 최근 반도체 패키지의 소형화에 따라 인쇄된 마크문자의 틀어짐 정도가 관리기준에 미달되는 문제가 발생되고 있다. 본 논문에서는 마크문자의 검사 항목 중 tilted mark(angle mark) 검사를 위한 회전량 측정방법으로 golden section searching 방법을 적용한 고속 라돈 변환(radon transform)방법을 제안한다. 실험에서는 제안한 방법이 일반적인 라돈 변환에 비해 최대 약 21 배의 회전량 측정속도가 향상되는 것을 확인하였다.

• 농업과학연구
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• 제49권4호
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• pp.677-696
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• 2022

Development of radish collectors may enhance radish production and promote upland crop mechanization in the Republic of Korea. Theoretical analysis of power is crucial to ensure the optimum design of agricultural machinery. The aim of the present study is to analyze theoretically the power requirement of a tractor-mounted radish collector under development and to propose design guidelines. The important components of the radish collector were belt-type conveyors, three hydraulic motors, and a direct current (DC) winch motor to operate the total radish collecting process. Theoretical equations were used to calculate the hydraulic motor's power, winch motor power, and draft power at loaded and unloaded conditions. A variety of tractors (44 - 74 kW) and different soil characteristics (hard, firm, tilted, and sandy) were considered to investigate the appropriate drawbar power. Variations of the power requirement of the tractor-mounted radish collector were observed due to modifications of the design parameters. The required hydraulic power of the stem cutting conveyor, stem cutting blade, and transfer conveyor of the radish collector were 0.23 and 0.24, 0.18 and 0.19, and 0.19 and 0.22 kW under unloaded and loaded conditions, respectively. The maximum draft power was calculated as 0.89, 1.07, 1.25, and 1.61 kW at a 30° tilted angle for hard, firm, tilted, and sandy soil, respectively. The calculation showed 2.07 kW DC power was required for unfolding or folding the stem-cutting conveyor. A maximum power of 4.78 kW was prescribed for conducting the whole process of the tractor-mounted radish collector. The analysis of power introduced in this study will be helpful to select the appropriate design parameters for the successful development of a tractor-mounted radish collector.

• 대한치과의사협회지
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• 제56권3호
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• pp.134-141
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• 2018

Purpose: To measure the head tilting angle creating initial condylar cut-off and to find the head position inducing the superimposition of the cervical vertebrae over the mandibular ramus on panoramic radiograph. Materials and Methods: The panoramic radiographs were taken with Didactic skull on cervical spine model (Scientific GmbH, Hamburg, Germany) using Kodak 8000c Digital Panoramic radiography. For the inherent radiolucency of the plastic skull model, radiopaque 1 mm diameter lead wires were attached along the margin of the mandibular condyle, ramus, mandibular body, cervical vertebrae, and FH plane of the skull model. For measuring the head tilting angle creating the condylar head cutoff, panoramic radiographs were taken by tilting the FH plane downward in 5 degree increments. For finding the distance between transverse process of the third cervical vertebra and gonion inducing superimposition of cervical vertebrae on the mandibular ramus, panoramic radiographs were taken by decreasing the distance in 0.5 cm increments. Result and Conclusion: The condylar cutoff began to appear when the head of skull model was tilted downward by 15o. As the head tilting angle increasing, the condylar cutoff became more prominent. The superimposition of cervical vertebrae over the mandibular ramus began to appear when the distance between the gonion and third cervical vertebra was 1.0 cm. As the distance decreasing, the superimpostion became more prominent.