• 한국안광학회지
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• 제10권3호
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• pp.247-253
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• 2005

본 논문에서 우리는 저시력용 갈릴레이식 망원안경을 설계하였는데 독일 제품을 참조하였다. 설계에 사용한 배율은 일반적인 용도를 위한 2.2X로 하였고, 구경 스탑(aperture stop) 의 크기는 3mm로 하였다. 본 갈릴레이식 망원안경은 Kidger Optics사의 Sigma2100 S/W로 설계하였다. 설계 결과 우리는 MTF 0.25 기준에서 0.25 cycles/arc-minute의 선폭을, 왜곡수차 1% 이내의 수차를 가지는 시스템을 구성할 수가 있었다. 본 시스템은 저시력용으로 유용할 것으로 판단된다.

• 한국정밀공학회지
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• 제4권2호
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• pp.36-46
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• 1987

An optical technique using laser for non-contact measurement of surface roughness and form accuracy of ground surfaces is presented. It is found that, when a ground surface is illuminated by a beam of laser light, the roughness height and slope distribution has significant influence on the pattern of reflection and it maintains an unique Gaussian distribution relationship with the surface roughness. The principle idea of the optical measurement system is therefore monitor the radiation, and then calibrate it in process against surface roughness by means of necessary digital data processing. On the other hand, measuring the form accuracy of a ground surface is accomplished by using a triangular method, which is based on observing the movement of an image of a spot of light projected onto the surface. The image is focused, through a series of lenses for magnification, on a photodetector array lf line configur- ation. Then the relative movement of image and consequently the form accuracy of the surface can be obtained through appropriate calibration procedures. Experimental test showed that the optical roughness measurement technique suggested in this work is very efficient for most industrial applications being capable of monitoring the roughness heights ranging 0.1 to 0.6 .$\mu$m CLA values. And form accuracy can be measured in process with a resolution of 10 .$\mu$m.

• 지질공학
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• 제25권2호
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• pp.165-178
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• 2015

Physical and chemical weathering degrades rock, affecting its structural properties and thus the stability of stone buildings or other structures. Confocal laser scan microscopy (CLSM) is used here to observe temporal changes in the surface roughness of rock samples under simulated accelerated weathering. Samples were pressurized to 50, 55, or 70 MPa using a pressure frame, and subjected to freeze/thaw cycling controlled by a thermostat. The temperature was cycled from -20℃ to 40℃ and back. After each 20 cycles, CLSM was used to assess the change in surface roughness, and roughness factors were calculated to quantify the progression of the surface condition over time. Variations in cross-section line-roughness parameters and surface-roughness parameters were analyzed for specific parts of the sample surfaces at 5× and 50× magnification. The result reveals that the highest and lowest values of the roughness factors are changed according to elapsed time. Freezing/thawing at high pressure caused larger changes in the roughness factor than at low pressure.

• 여성건강간호학회지
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• 제10권2호
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• pp.162-170
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• 2004

Purpose: The purpose of this study was to differentiate between women with three perimenstrual symptom severity patterns : premenstrual syndrome(PMS), premenstrual magnification(PMM), and low symptom(LS), and to explore the related dietary factors to premenstrual symptoms. Method: Women were asked to keep a diary record of perimenstrual symptoms and food intake for 50 days. Result: Symptom patterns were defined for 26 among 38 women ; Eight(21.1%) demonstrated a PMS pattern, three(7.9%) demonstrated a PMM pattern, and fifteen(39.5%) exhibited a LS pattern. There were significant differences in symptom scores during the premenstrual phase($x^2=19.30$, p=.000), menstrual phase($x^2=13.32$, p=.001), and post menstrual phase($x^2=9.93$, p=.007) for three groups. Protein, vit E, vit C, niacin, folic acid, and phosphorus in the premenstrual phase, and energy, and vit B6 in the menstrual period were significantly different between the three groups. Among dietary compositions, amino acids, lipids, fatty acids, saturated fatty acids, natrium, vit B6, niacin, and vit E were negatively related to PMS symptoms. Conclusion: Pattern of perimenstrual symptoms should be differentiated for individualized PMS management. As a more efficient diet assessment for PMS women, randomized nutritional analysis during the 3 phases of the menstrual cycle should be done and a replication study is necessary with a larger sample.

• 정보관리학회지
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• 제21권4호
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• pp.295-314
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• 2004

문화란 정보사회를 살아가며 누리고 있는 물질적, 정신적 생활양식의 복합체로 볼 수 있다. 즉 어떤 특정지역의 구성원들이 공유하고 있는 습득된 지식, 믿음, 기술, 행동들을 모두 포함하는 생활양식이다. 사람들은 정보와 문화가 새로운 부가가치를 창출하는 시대라고 한다. 이와 같은 두 가지 개념의 공통점은 보이지 않은데 있으며, 인간의 내면의 세계에서 창조되는 것으로 수많은 경험과 체험에서 나온다고 볼 수 있다. 이러한 정보문화가 글로벌화 되고 있다. 따라서 이 연구에서는 정보문화의 확산을 위해 필요한 이론적 근거로서 사례를 중심으로 정보문화 창조과정의 모형을 제시하고 있다.

• 한국콘텐츠학회:학술대회논문집
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• 한국콘텐츠학회 2007년도 추계 종합학술대회 논문집
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• pp.691-697
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• 2007

참여와 개방, 공유'로 특징지어지는 웹 2.0의 등장과 함께 UCC는 앞으로 웹 비즈니스를 이끌어갈 핵심 키워드로 주목받고 있다. 그러나 일반 소비자가 생산에 적극적으로 참여하는 프로슈머가 확산되고, 신규 플랫폼의 개발로 UCC의 영향력이 계속 확대되고 있음에도 불구하고 뚜렷한 UCC 비즈니스 모델이 없어서 현재 국내외 업계에서는 이를 타개하기 위해 다양한 노력을 펼치고 있다. 본 논문은 UCC 비즈니스 모델 수립을 위한 기초 연구로서 현재 UCC 서비스 업계의 현황 분석을 통해 그 발전 전망을 살펴보고자 하였다. 즉, UCC 개념과 유형을 살펴보고, 국내외 UCC 서비스의 현황 분석을 통해 기술발전의 방향, 수익모델 등을 살펴보고, UCC 서비스의 문제점 등을 도출하였다. 이를 바탕으로 앞으로 UCC 서비스의 발전 방향에 대해 가늠해 보고자 한다.

• 연구논문집
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• 통권34호
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• pp.79-85
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• 2004

There are several types of life test method for hose assemblies. The two major tests used for hose assemblies are impulse test and burst test. And magnification adjustment of impulse pressure, heating of testing oil and repetitive motions of bending and straightening of testing hose are also performed for accelerating the life. According to the manufacture process of hose and swaging process of fitting, there is a difference in the life of hose assemblies from minimum 7 times to maximum 40 times during the life test in the same functioning condition. Like this, the life test of hose which has a wide scope of life distribution gives a problem that observation should take a long time to find out the existence of the bursting from the beginning of the test to the completion of bursting of hose assemblies. Therefore, this research proposes a process of concentrating on the defective section of hose assemblies and maximizing the life acceleration by giving 'Knockdown stress' to hose assemblies just until before the hose assemblies get out of order.

• 한국강구조학회 논문집
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• 제12권1호통권44호
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• pp.103-110
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• 2000

현수교는 정착 형식에 따라 타정식과 자정식으로 나누는데, 본 연구는 이 두 가지의 정착 형식의 이동하중에 대한 동적 효과의 차이를 살펴보기 위한 것으로, 연구 결과를 동적확대계수를 차량의 속도와 중량의 효과에 대해 제시함으로써 살펴보았다. 본 연구에 유한요소법을 이용하였다. 비선형 다엽식 현가장치와 트랙터-트레일러의 타이어를 모델링하기 위해 6자유도 시스템으로 차량을 모델링 하였다. 교량은 3차원 프레임 요소와 3차원 탄성현수선 요소로 모델링하였다. 바닥판 상부의 조도를 실제의 도로로부터 얻은 스펙트럼으로부터 노면형상을 생성하여 사용하였다.

• The Journal of Advanced Prosthodontics
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• 제7권1호
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• pp.76-84
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• 2015

This article reviews the topic of how to identify and develop a removable partial denture (RPD) path of placement, and provides a literature review of the concept of the RPD path of placement, also known as the path of insertion. An optimal RPD path of placement, guided by mutually parallel guide planes, ensures that the RPD flanges fit intimately over edentulous ridge structures and that the framework fits intimately with guide plane surfaces, which prevents food collecting empty spaces between the intaglio surface of the framework and intraoral surfaces, and ensures that RPD clasps engage adequate numbers of tooth undercuts to ensure RPD retention. The article covers topics such as the causes of obstructions to RPD intra-oral seating, the causes of food collecting empty spaces that may exist around an RPD, and how to identify if a guide plane is parallel with the projected RPD path of placement. The article presents a method of using a surgical operating microscope, or high magnification (6-8x or greater) binocular surgical loupes telescopes, combined with co-axial illumination, to identify a preliminary path of placement for an arch. This preliminary path of placement concept may help to guide a dentist or a dental laboratory technician when surveying a master cast of the arch to develop an RPD path of placement, or in verifying that intra-oral contouring has aligned teeth surfaces optimally with the RPD path of placement. In dentistry, a well-fitting RPD reduces long-term periodontal or structural damage to abutment teeth.

• 대한치과기공학회지
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• 제30권1호
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• pp.131-139
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• 2008

It's very important to find the most appropriate adhesion technique available, taking into consideration factors such as biocompatibility, non-corrosiveness, mechanical stability, etc. Laser welding is the best choice you can make because from a mechanical viewpoint, a laser welded surface has better particle structure than does a casted particle structure. Furthermore, it requires no additional material and the same metal alloy which is used when casting can be used. Therefore, the resulting mixture will consist of a single alloy, instead of utilizing different alloy combinations. Another benefit is the low economic cost. The most beneficial aspects of laser welding is that it is biologicallly friendlly, doesn't require soldering, can fuse different metal alloys together, and can weld on heat-sensitive spots(E.g. around resin or ceramic). A consistent strong pulse is possible. This technique is capable of welding on master models and creates accurate welds. It is capable of due to its stronger, non-corrosive microscope, which allows 25times magnification during the soldering process. This is possible because of its high stability from the tiny particle structure.