• 열처리공학회지
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• 제7권2호
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• pp.118-128
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• 1994

Five alloys were selected randomly in the composition range showing the best shape memory effect in Fe-Mn-Si system reported by Murakami. The shape memory effects of those alloys were mainly investigated through the training treatment which consisted of the repetition of 2% tensile deformation at room temperature and subsequent annealing at $600^{\circ}C$ above $A_r$ temperature. At the same deformation degress in rolling $600^{\circ}C$-annealing for 1 hr. showed the best shape memory effect, and 10%-deformation degrees represented maxima of the shpae memory effects at all annealing temperatures, $500^{\circ}C$, $600^{\circ}C$ and $700^{\circ}C$. The shape memory effects of the alloys were increased by increasing training cycle up to 5 cycles. This was because a large number of dislocations introduced by training process gave rise to increase in the austenite yield stress, and acted as nucleation sites for stress induced ${\varepsilon}$ martensite. The thermal cycling treatment, repetition of cooling in nitrogen at $-196{\circ}C$ and heating to $300^{\circ}C$ for 5 min., did not improve the shape memory effect.

• 제어로봇시스템학회논문지
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• 제5권3호
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• pp.353-362
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• 1999

This paper presents a shape reconstruction method for automatic inspection of the solder joints on PCBs using X-ray. Shape reconstruction from X-ray radiographic image has been very important since X-ray equipment was used for improving the reliability of inspection result. For this purpose there have been lots of previous works using tomography, which reconstructs the correct shape, laminography or tomosynthesis, which are very fast algorithm. Latter two methods show outstanding performance in cross-sectional image reconstruction of lead type component, but they are also known to show some fatal limitations to some kinds of components such as BGA, because of shadow effect. Although conventional tomography does not have any shadow effect, the shape of PCB prohibits it from being applied to shape reconstruction of solder joints on PCB. This paper shows that tomography using Iterative Reconstruction Technique(IRT) can be applied to this difficult problem without any limitations. This makes conventional radiographic instrument used for shape reconstruction without shadow effect. This means that the new method makes cost down and shadow-free shape reconstruction. To verify the effectiveness of IRT, we develop three dimensional model of BGA solder ball, make projection model to obtain X-ray projection data. and perform a simulation study of shape reconstruction. To compare the performance of IRT with that of conventional laminography or tomosynthesis, reconstruction data are reorganized and error analysis between the original model are also performed.

• 한국유체기계학회 논문집
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• 제11권4호
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• pp.45-51
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• 2008

The purpose of this study is to examine the effect of nozzle shape on the performance and internal flow of a cross-flow hydro turbine. CFD analysis for three kinds of nozzle shape is conducted to simulate the effect of nozzle shape. The results reveal that relatively narrow nozzle width is effective to increase the turbine efficiency and output power. Almost output power is achieved at Stage 1. Therefore, optimum design of the nozzle shape is necessary to improve the turbine performance. Recirculation flow in the runner passage decreases the turbine efficiency and output power because the flow make hydraulic loss and collision loss in the region. Air should be put into the runner passage and the recirculating flow should be suppressed by the air layer in the runner.

• 한국군사과학기술학회지
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• 제21권2호
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• pp.180-187
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• 2018

In this study, we develop a prediction method of cavity shape taking gravity effect and angle of attack of cavitator into consideration simultaneously. Logvinovich's theoretical formulas are superimposed to predict the change of cavity centerline due to both gravity effect and angle of attack of cavitator. It is found that as the angle of attack of cavitator increases, the gravity effect is weakened due to decrease in cavity volume, and even in case of the same angle of attack, cavity shape changes in different ways depending on whether the angle of attack of cavitator is positive or negative. We conclude that cavity shapes are largely affected by the angle of attack of cavitator, and the gravity effect and angle of attack of cavitator should be considered at the same time for the prediction of cavity shape.

• 패션비즈니스
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• 제9권2호
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• pp.28-39
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• 2005

This chapter presents how 'optical illusion' works in applying makeup and how to differentiate the direction, location and shape at eyebrow lines in the aspect at physiognomy. For this study, employed were five types of face shape produced by Photoshop program - round, square, long, inverted triangle. and diamond. The best-matched facial shape was examined through a questionnaire research after applying the optical illusion of eyebrow lines to the five types of face shape. The results were revealed to be identical to ones presented in make-up teaching materials. In conclusion, it was found that well-matched shape and size of eyebrow could make some changes in the facial impression, changing the face shape into oval shape. The facial line can be modified and supplemented by reshaping such facial parts as the eyebrow, producing well-balanced facial shape. Consequently, make-up was proved to be one of the methods which can be used to create social and psychological effect which can make a favorable facial impression and individuality, natural impression and image making depending on different purposes, taking advantage of optical illusion effect.

• 패션비즈니스
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• 제12권1호
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• pp.164-172
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• 2008

A face is the place where individuals can first give their images visually. This chapter presents how 'Visual optical illusion' works in applying makeup and how to differentiate the direction, location and shape of Lip in the aspect of physiognomy. For this study, employed were five types of face shape produced by Photoshop program. The best-matched facial shape was examined through a questionnaire research after applying the optical illusion of Lip to the five types of face shape. The results were revealed to be identical to ones presented in make-up teaching materials. In conclusion, it was found that well-matched shape and size of Lip could make some changes in the facial impression, changing the face shape into oval shape. The facial line can be modified and supplemented by reshaping such facial parts as the Lip, producing well-balanced facial shape. Consequently, make-up was proved to be one of the methods which can be used to create social and psychological effect which can make a favorable facial impression and individuality, natural impression and image making depending on different purposes, taking advantage of optical illusion effect.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2011년 춘계학술대회논문집
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• pp.58-64
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• 2011

The objective of this paper is to investigate the gravity effect on the shape characters of natural supercavity. A finite difference solver along with an implicit, dual time, preconditioned, three-dimensional algorithm has been used to solve the two-phase Navier Stokes equations. Numerical solutions were performed for natural supercavitating flow past a disk for different cavitation and Froud numbers. The numerical results were compared with corresponding analytical results in quantitative manner and it was found that the shape of supercavity was reasonably predicted Numerical results indicated that the gravity effect can induce the asymmetry of supercavity. The asymmetry was apparent when the froud number was smaller so that for constant cavitation number when we reduced the froud number the opt of the axis of supercavity increased. Moreover, for specific froud number a decrease in cavitation number resulted in an increase in the offset of the supercavity Numerical results revealed that for froud number greater than 25 the gravity effect is negligible.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1990년도 가을 학술발표회 논문집
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• pp.113-116
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• 1990

This study is designed to analyze the variation of grading and shape of aggregate with the number of rotations of Los-Angeles abrasion machine, and is aimed to analyze the effect of slump and compressive strength of strength of concrete with the shape of coarse aggregate by the abrasion act.

• 설비공학논문집
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• 제16권4호
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• pp.374-382
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• 2004

Diffuser design is crucial for water-chilled heat storage. Its impact on the system performance is more significant for the underground tank due to inherent limit on the aspect ratio and tank shape. The effect of diffuser shape on the performance of the water-chilled heat storage is numerically investigated. Three dimensional simulation has been conducted for fully incorporating the complex diffuser shape and the non-symmetric tank shape. Mixing at the inlet of the diffuser depends on the inlet Reynolds number, Froude number and the diffuser shape. Three types of the diffuser shape and the broad range of Reynolds number (Re=400, 800, 1200) and Froude number (Fr=0.5, 1.0, 2.0) are examined. The performance of the heat storage tank is evaluated by the thermocline thickness which is reverse to the degree of stratification. The radial regulated plate diffuser, which is the suggested diffuser shape in this study, shows the lowest thermocline thickness in the condition considered.

• International Journal of Advanced Culture Technology
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• 제5권1호
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• pp.17-25
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• 2017

The purpose of this study was to investigate the effects of self-identity on body shape management for college students. This study used descriptive research to analyze the effects of self-identity, which has contained factors of Subjectivity, Self-acceptance, Future Confidence, Goal Orientation, Scrupulous. The subjects were 404 college students located in C province who were voluntarily agreed. Multiple regression analysis was conducted to verify the effects on self - identity and body shape management. As a result, self - acceptance of self - identity' subcomponents had no effect on body shape management, but future confirmation, goal orientation, Scrupulous, intimacy affects body shape management(P < 0.001). Based on these results, in order to manage the body shape of college students, it is considered effective to present the visible goals and apply the programs that students can do themselves. In addition, it can be seen that it is effective to start body shape management during college group life to enhance intimacy.