• Journal of Mechanical Science and Technology
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• v.20 no.5
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• pp.710-716
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• 2006

Micro-PIV system with a high speed CCD camera is used to measure the flow field near the advancing meniscus of a water slug in microchannels. Image shifting technique combined with meniscus detecting technique is proposed to measure the relative velocity of the liquid near the meniscus in a moving reference frame. The proposed method is applied to an advancing front of a slug in microchannels with rectangular cross section. In the case of hydrophilic channel, strong flow from the center to the side wall along the meniscus occurs, while in the case of the hydrophobic channel, the fluid flows in the opposite direction. Further, the velocity near the side wall is higher than the center region velocity, exhibiting the characteristics of a strong shear-driven flow. This phenomenon is explained to be due to the existence of small gaps between the slug and the channel wall at each capillary corner so that the gas flows through the gaps inducing high shear on the slug surface. Simulation of the shape of a static droplet inside a cubic cell obtained by using the Surface Evolver program is supportive of the existence of the gap at the rectangular capillary corners. The flow fields in the circular capillary, in which no such gap exists, are also measured. The results show that a similar flow pattern to that of the hydrophilic rectangular capillary (i.e., center-to-wall flow) is always exhibited regardless of the wettability of the channel wall, which is also indicative of the validity of the above-mentioned assertion.

• Transactions of the Korean Society of Mechanical Engineers
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• v.16 no.5
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• pp.849-863
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• 1992

A very simple and computationally efficient numerical method is developed for the free vibration of isotropic and orthotropic composite triangular plates. A set of two-dimensional simple series functions is used as an admissible displacement functions in the Rayleigh-Ritz method to obtain the natural frequencies, nodal patterns and mode shapes for the plates. From the prescribed starting function satisfying only the geometric boundary conditions, the higher terms in the series functions are constructed with adding order of polynominal. Natural frequencies, nodal patterns and mode shapes are obtained for right triangular plates with three different support conditions. The obtained numerical results are presented, and the isotropic and some orthotropic cases are verified with other numerical methods in the liternature.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.35 no.4
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• pp.417-424
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• 2011

A fuel assembly consists of five major components, i.e., a top end piece (TEP), a bottom end piece (BEP), spacer grids (SGs), guide tubes (GTs) and an instrumentation tube (IT); in addition, it also includes fuel rods (FRs). The TEP/BEP should satisfy stress intensity limits according to the conditions A and B of ASME, Section III, Division 1-Subsection NB. In a dual-cooled fuel assembly, the array and position of fuel rods are different from those in a conventional PWR fuel assembly; these changes are necessary for achieving power uprating. The flow plates of the TEP and BEP have to be modified accordingly. The pattern and shape of the flow holes were newly designed. To verify the strength compatibility, the Tresca stress limit according to the ASME code was investigated in the case of an axial load of 22.241 kN. In this paper, the stress linearization procedure for strength evaluation of a newly designed TEP is presented.

• The Journal of Korean Medicine
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• v.25 no.1
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• pp.1-20
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• 2004

Objectives : Based on the analysis of Yin-Yang[음양] characteristics and symptoms, each person is classified into Yin-Yang. Also the validity of the result is statistically analized. Methods : From Feb. to May. 2003, the data were collected through a questionnaire given to 690 patients. The questionnaire was composed of 34 items which were about personality, habit, sweat, response to coldness, thirst, bowel, urine, physical shape, and menstruation for women only. SD(Semantic Differential Technique) used for each item, each item is measured as a contrast of two opposite symptoms. Reliability analysis was used to select items and categories. Based on means of items in each category the Yin-Yang index was developed. The validity of Yin-Yang index was investigated using classification and clustering analysis. In statistical analysis, SPSS V10.0.7 PC was used. Results : The obtained results are summarized as follows: 1) We constructed Yin-Yang index based on the middle point of the sum of categorical means. Then we classified each person into Yin or Yang. 2) To investigate the validity of the distribution of personal Yin-Yang degree, the crosstabulation of results from clustering and classification was used. The hit ratio for classification was much higher than Maximum Chance Criterion($C_{max}$), and concurrence in crosstabulation was successful. Therefore we can infer that the distribution of Yin-Yang was valid. Conclusions : Based on Yin-Yang characteristics and symptoms, we was analyzed personal degree of Yin-Yang, and confirmed the validity of its distribution. Therefore this index can be used further for Bian-Zheng [변증] and classification of the constitution.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.16 no.7
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• pp.1495-1504
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• 2012

This paper proposes an algorithm to classify and analyze facial features such as eyebrow, eye, mouth and chin based on the geometric features of the face. As a preprocessing process to classify and analyze the facial features, the algorithm extracts the facial features such as eyebrow, eye, nose, mouth and chin. From the extracted facial features, it detects the shape and form information and the ratio of distance between the features and formulated them to evaluation functions to classify 12 eyebrows types, 3 eyes types, 9 mouth types and 4 chine types. Using these facial features, it analyzes a face. The face analysis algorithm contains the information about pixel distribution and gradient of each feature. In other words, the algorithm analyzes a face by comparing such information about the features.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.47 no.11
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• pp.779-786
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• 2019

Effects of chamfered perforated plate on pressure loss characteristics were studied with CFD analysis. Both inlet chamfer angle and outlet chamfer angle were considered. Perforated patterns were compared by pressure loss coefficient in certain porosity and Reynolds number. Reynolds number effects were studied for several chamfer angles and plate thickness. As the inlet chamfer angle was increased, the pressure loss coefficient was decreased until the certain angle and reversed to increase. In the outlet chamfered shape cases, the pressure loss coefficient was increased with chamfer angle. Effects of pattern shapes and Reynolds number on pressure loss characteristics were negligible with different chamfer angles and thickness studied in this paper.

• Journal of the Korean Society of Costume
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• v.27
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• pp.163-171
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• 1996

As the current stage of the fashion begins to follow the styles of the past the study on he past costume is getting more importance and as the methodology of the study the accurately ap-proached study through the rehabilitation of the past costume is more needed than the simple re-arrangement of the historical documents. By this methodology this study can be positioned as a re-creation activity. The results of the study are as follows. 1) Style: The S-line silhouette remains be-cause of the straight silhouette or the blossom style bodice. This dress has various types of sil-houette but generally it forms one silhouette and is one-piece. 2) color and Material: The material varies hile the color is divided as the main color of ivory and the stress color of brown. This shows not only that the material has been varied but also that they tried to reduce the monotony. 3) Pattern and Sewing: The simple external figure and the previous stage typically shows the movement to the simplicity of the contemporary and the num-ber of patterens is plenty and the sewing method is also complex. 4) Detail. To overcome the simplicity of the style and to show the characteristics of the afternoon dress the skunk fur the net the sash, and the bow are used. 5) Structural Characteristics: The front open-ing the back opening and the side opening coexists in one-pieced dress and this forms unique structure and complex fastening device. The ribbon tape and casing not only finish the seam but also fix the shape of the dress. Synthetically the 1913-14 afternoon dress has the characteristics of transitional stage in which the characteristics of the costume of 1910s and the remnants of the characteristics of the pre-vious costume style and shows the character-istics of afternoon dress well in terms of the ma-terial the structure and the detail.

• Journal of the Korean Society of Costume
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• v.65 no.4
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• pp.1-18
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• 2015

The subject of study is about the illustrations of the round collar Po(袍類) in the Akhak-gwebeom(樂學軌範) which was published in 1493. These illustrations are painted records of what musicians and dancers in the palace were wearing during performances. While each illustration of the Po is similar in that they all have round collars, each has a different name Sam(衫), Ui(衣), Dallyeong(團領) and formative characteristics, and these features were analyze in the study. Sam refers to the Gongbok(公服) as it has long and big sized sleeves, Ui is the word used to represent the basic unit of outerwear, and Dallyeong is believed to refer to the Sibok(時服) and Sangbok(常服). In the formative aspects, Sam's auxiliary sleeve is one of the ways wearing the sleeve of innerwear shown outward and it's assumed to have been produced for visually matching the formal look as well as the convenience free to use of hands. The Mu of Dan-ui(丹衣) is less than the number of the excavated artifacts, it produced in a relatively simplified form. Also, illustration of Dallyeong corresponds to the artifacts and configuration of the 15th to 16th centuries, the costume culture of that time seems to be reflected specifically. While Hyungbae(胸背) used in the form of rectangles and circles such as petals. it tried to represent the country at the official event by borrowing the upper class in the costume that musicians and dancers wear, also showed the rank and social status symbolically by having the differences in the shape and pattern. While the costume culture at the time is reflected, it can be found that the objective of raising the country's dignity is implied by transforming the detailed structure for the practicality, borrowing the costume elements of the high social status and transformed them.

• Journal of the Korean Society of Costume
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• v.61 no.6
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• pp.60-73
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• 2011

Men's fashion has not much changed due to the pervasive patriarchy Because of the change of gender roll and attitude towards one's appearance and fashion, men began to express themselves with fashion in the late 90's. The purpose of this study is to categorize men's image and their fashion styles from Korean TV dramas to provide informations for predicting men's fashion trend in rapidly changing market. Through the analysis of three dramas with 30% or more of audience rating by all age groups from January to July, 2009, nine distinctive male images were selected and their styles were analyzed; silhouette, details, materials, color, accessories, and hair-style. The results are as follows: In the past holding neat and straight line silhouettes but today shows tight silhouette. In color and detail, the use of brilliant chromatic colors, use of hight saturation colors, big and brilliant pattern, ruffles, frills, beads, knitwear, mix matched new composed materials, and light materials are dominant. While short and simple shape of hair-styles were predominant in the past, now we see more varied hair length. Not only that, variety of perms and colors are showed on TV screens. Hence, the results show that a lot of radical change has happened in the men's fashion, and marketing propositions that reflects this change in men's fashion market are requested along with trendy emotional product development and coordination proposals, and finally calls for more multilateral study and market search of male consumers.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.6 no.3
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• pp.273-277
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• 2005

We prepared $0.25\~l.5um$ poly silicon gate array test group with $SiO_2$ spacers in order to employ NiCo composite salicide process from 15nm Ni/15nm Co/poly structure. We investigate the residual metal shape evolution by varying the rapid thermal silicide anneal temperature from $700^{\circ}C\;to\;1100^{\circ}C$. We observed the residual metals agglomerated into maze type and line type on $SiO_2$ field and silicide gate, respectively as temperature increased. We propose that lower silicide temperature would be favorable in newly proposed NiCo salicide in order to lessen the agglomeration causing the leakage and scum formation.