• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2000년도 추계학술대회 논문집
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• pp.93-96
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• 2000

This study discusses a non-contact optical technique, phase shifting electronic speckle pattern interferometry, that is well suited for a deformation measurement. However, the phase shifting method has difficulties for determinating a deformation quantitatively beacuse of the characteristics of arctan function. In order to solve this problem, phase unwrapping methods has been studied during the last few years. In this study, using phase unwrapping based on line by line scanning phase shifted fringe patterns are studied to determinate a deformation quantitatively. Also least square fitting method is applied to reduce noise and improve image resolution.

• 대한가정학회지
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• 제47권4호
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• pp.83-98
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• 2009

he purpose of this study was to assess if the availability of the family-friendly corporate welfare programs had an effect on job satisfaction of married female employees after controlling for other factors such as job, personal and household characteristics. This study analyzed 215 working mothers who had the children under 6 years of age using the Korea Labor Panel Data(2005). The study established that married female employees working in the companies with more family-friendly corporate welfare programs exhibited higher job satisfaction on working hours, communication and human Relationships and other fringe benefits. Therefore, we recommended that family-friendly corporate welfare programs should be more available and developed in order to promote better job satisfaction for married female employees.

• 한국의상디자인학회지
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• 제5권3호
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• pp.25-36
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• 2003

The purpose of this study is to analyze the expressive technique of grunge look in knitwear fashion. For this study, I have investigated theories of retro and decontructionism trends, and have examined pictures from professional fashion magazines. The results of study on the expressive technique of grunge look reflected on the knitwear fashion were as follows; (1) patchwork technique, which is an outstanding method of recycling, (2) handknitting technique, which came from retro trend of hippism, (3) unfinished edge, which emphasized the image of poverty and incompleteness, (4) irregular lace knitting and slash technique, which is the typical details of grunge look and denies the traditional fashion order, (5) hand stitch technique using various materials, which gives second-hand mood of hippie look, and (6) fringe details, which originated from the unfinished edge technique.

• 대한기계학회논문집A
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• 제20권10호
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• pp.3211-3223
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• 1996

In this paper, the propagation of elastic wave generated by loading impact to plates made of isotropic of anisotropic material was studied. And the influence of boundary conditions (free or clamped edge) upon the reflection of elastic wave was anlyzed. Also, double exposure holographic interferometer using ruby pulse laser was formed in order to investigate transient waves. Before the elasitc wave was reflected from the edges, the elastic wave of isotropic plate such as aluminum plate showed circular interferometric fringe pattern, whereas that of anisotropic plate such as epoxy composite laminates showed elliptical one. And the transverse displacement curves obtained from experiment and theory for both plates agreed well. Also, the waves reflected from the boundary edges showed much differences according to the boundary condition of edges.

• 대한기계학회논문집
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• 제12권4호
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• pp.806-812
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• 1988

본 연구에서는 상술한 바와 같이 광간섭에 의한 포성재료 및 초저온, 초고온 에 사용되는 재료의 응력확대계수 측정법에 대한 응용의 한 방법으로서 테프론 균열 주형법에 의한 인공열을 에폭시(epoxy)판으로 주형하고 레이저 간섭법에 의한 응력 확대계수의 측정을 시도하여 광소자(phototransistor)로 추적하기에 적당하고 선명한 간섭무늬를 얻을 수 있는 판사면 중심간의 구이를 실험적으로 결정하고 광탄성법에 의 한 실험결과와 비교하여 레이저 간섭법의 실용성을 확인하려고 한다.

• 한국환경교육학회:학술대회논문집
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• 한국환경교육학회 2002년도 후반기 정기 학술발표대회
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• pp.79-85
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• 2002

Inquiry activity contents presented at a chapter on natural environment and our lives in 6 science textbooks of the middle school were analyzed based on kinds of the inquiry Loaming classified by textbook. The number of inquiry activity subjects showed severe variation as mean value was 8.3${\times}$3.7 ranged from 4 to 15. Moreover, textbooks had little common point among each other as the percentage of subjects appeared together in the textbooks more than 3 kinds, 50% of total ones investigated, was just 26.3%. Data interpretation occupied significant position in the inquiry activity as 42% of total activity contents, whereas observation and experiment (or survey) did slight part of the activity as 10% and 16%, respectively even though they are main factors of science education. A model for field education based on the reasonable common subjects was prepared in the Gildong ecological park located In the eastern fringe of Seoul as a plan in order to solve the problems.

• 대한기계학회논문집A
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• 제28권11호
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• pp.1646-1655
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• 2004

A description of the basic principles of moire interferometry leads to the design of a eight-mirror four-beam interferometer for obtaining fringe patterns representing contour-maps of in-Plane displacements. The technique is implemented by the optical system using an environmental chamber for submicro-displacement mesurement. In order to estimate the reliability and applicabili쇼 of the system developed, the measurement of coefficient of thermal expansion (CTE) for a aluminium block is performed. Consequently, the system is applied to the measurement of thermal deformation of a WB-PBGA package assembly. Temperature dependent analyses of global and local deformations are presented to study the effect of the mismatch of CTE between materials composed of the package assemblies. Bending displacements of the packages and average strains of solder balls are documented. Thermal induced displacements calculated by FEM agree quantitatively with experimental results.

• 대한치과보철학회지
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• 제31권4호
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• pp.679-686
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• 1993

The osseointegrated implant conducts the stress directly to the bone due to lack of cushoning effect of periodontal ligament. So, the design and material quality of superstructure plays an important role in resolution and diffusion of stress. Recently, the various superstructures have been developed to improve esthetics and resolve various complicated conditions. The purpose of this study was to evaluate the stress induced by various system on the osseointegrated implant using UCLA abutment, EsthetiCone abutment, Anatomic abutment as well as Branemark conventional abutment. The stress distribution was evaluated by the photoelastic method which can simultaneously observe all around stress distribution. The superstructures embedded in epoxy resin specimen were loaded at various angle with a force of 15Kg to analyse the stress distribution of the fixture. The results of this study were obtained as follows : 1. Under vertical loading, the large and broad stress was distributed below the fixture in all systems. 2. The fringe order of the stress was increased in proportion to tillting the specimen. The largest stress was shown in 25 angled degree tilting case. 3. The Branemark conventional abutment showed the lowest value, and EsthetiCone abutment, Anatomic abutment and UCLA abutment showed the stress value in accending order.

• 대한기계학회논문집
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• 제7권2호
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• pp.161-167
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• 1983

In this study the phenomenon of cutting stress which arises on cutting tools and work pieces in cutting process is investigated by rake angle of cutting tools and feed for this measurement, P$_{s}$-1 (high modulus, photolastic Inc.) was used as a cutting tool, P$_{s}$-3 (medium modulus, photolastic Inc.) was used as work piece and reduction apparatus was attached to the head stock, and orthogonal cutting was adapted as a cutting method and transparent glass was used to block the strain in the orientation of thickness. The followings are the results of this study. (1) Photoelastic experimental equipments have made it possible to make dynamic measurement and analyze stress distribution in cutting tool and work piece surface which has hitherto been conducted only in static measurement and analyzing method. (2) The maximum stress arising at tools and work pieces in cutting process is on the tool edge tip, and the maximum stress arising on the tip of cutting tools is equal to that on the contacting area of work pieces in values. (3) The distributions of maximum shear stress on certain parts of the cutting tools and work pieces are as follows; for cutting tools, .alpha.=12.deg., .alpha.=0.deg., .alpha.=-12.deg. in order, and for work pieces, .alpha.=-12.deg., .alpha.=0.deg., .alpha.=12.deg. in opposite order.der.

• 한국멀티미디어학회논문지
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• 제21권8호
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• pp.864-875
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• 2018

In this paper, we propose a measurement method for height of white light scanning interferometer using deep learning. In order to measure the fine surface shape, a three-dimensional surface shape measurement technique is required. A typical example is a white light scanning interferometer. In order to calculate the surface shape from the measurement image of the white light scanning interferometer, the height of each pixel must be calculated. In this paper, we propose a neural network for height calculation and use virtual data generation method to train this neural network. The accuracy was measured by inputting 57 actual data to the neural network which had completed the learning. We propose two new functions for accuracy measurement. We have analyzed the cases where there are many errors among the accuracy calculation values, and it is confirmed that there are many errors when there is no interference fringe or outside the learned range. We confirmed that the proposed neural network works correctly in most cases. We expect better results if we improve the way we generate learning data.