• Transactions of the Korean Society of Automotive Engineers
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• v.10 no.6
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• pp.178-186
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• 2002

3-D numerical studies are performed to investigate the effect of the trunk height and approaching air velocities on the pressure distribution of notchback road vehicle. For this purpose, the models of test vehicle with four different trunk heights are introduced and PHOENICS, a commercial CFD code, is used to simulate the flow phenomena and to estimate the values of pressure coefficients along the surface of vehicle. The standard k-$\xi$ model is adopted for the simulation of turbulence. The numerical results say that the height variation of trunk makes almost no influence on the distribution of the value of pressure coefficient along upper surface but makes very strong effects on the rear surface. That is, the value of pressure coefficient becomes smaller as the height is increased along the rear surface and the bottom surface. Approaching air velocity make no differences on pressure coefficients. Through the analysis of pressure coefficient on the vehicle surfaces one tried to assess aerodynamic drag and lift of vehicle. The pressure distribution on the rear surface affected more on drag and lift than pressure distribution on the front surface of the vehicle does. The increase of trunk height makes positive effects on the lift decrease but negative effects on drag reduction.

• Journal of the Korea Fashion and Costume Design Association
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• v.18 no.2
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• pp.15-33
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• 2016

Women in their 30s and 40s, who are at the center of "ageless" and "down-aging" consumer trends, are likely to encounter problems with fitting and size conformity when they wear casual clothes targeting women in their 20s. Hence, differences in upper body sizes and body types between women in their 20s and women in their 30s and 40s were analyzed. The data for this study was from the 6th Size Korea survey of body measurements of 1,675 female adults in their 20s-40s. SPSS 21.0 for Windows was used for analysis of the collected data. To examine differences in average upper body size between women in their 20s and women in their 30s and 40s, descriptive statistics and independent sample t-tests were conducted. Factor and cluster analyses were used to classify body types by age groups. Comparing direct measurement items showed that women in their 20s tend to have higher average values for most height-related items-including body height-and lower average values for circumference, thickness, and width than women in their 30s and 40s. Factors in determining the upper body shapes of women in their 20s to 40s were narrowed to five; through a cluster analysis, upper body shapes of women were classified into three body types as follows. Type 1 women are shorter and thinner with small frames; Type 2 women have the highest vertical values for their upper bodies and average values for obesity-related categories of circumference, thickness, and width. Type 3 women are the shortest and has the highest body mass index (BMI), verifiable as obese. By analyzing differences in body type distribution according to age groups, it was found that more than 90% of women in their 20s belong to Types 1 and 2. On the other hand, most women in their 30s and 40s are identified as Type 3.

• Journal of the Korea Fashion and Costume Design Association
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• v.20 no.2
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• pp.73-87
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• 2018

As men in their 30s are spending more money on clothing, it is becoming increasingly important to first conduct an anthropometric study and then develop garment patterns accommodating the changes found in body sizes and types of men in their 30s, in order to effectively address their fit dissatisfaction. Thus this study aims to explore changes in upper body sizes and body types of men in their 30s, which provide basic measurements for designing major garment items including jackets and shirts. To this purpose, key anthropometric dimensions of the upper body of men in their 30s, taken from the 6th (2015) and 7th (2016) surveys conducted by Size Korea, were analyzed using SPSS 24.0 for Windows. Independent sample t-tests were conducted on major upper body sizes to track changes with measuring time. Factor and cluster analyses were used to classify body types. By comparing the two surveys, it was found that the overall body sizes of men in their 30s were increasing in height-related items, circumference, thickness, and width, -as well as body weight and BMIs. Upper body height-related items, in particular, showed a higher average value in the 6th survey than in the 7th, indicating that the overall body types of men are becoming "westernized" with longer legs and shorter torso. Finally, five factors were derived to determine the typical upper body types of men in their 30s and the body types were classified into three categories according to the cluster analysis. First, those with a relatively small build with short stature and torso. Second, those with the highest stature and vertical dimension with the smallest torso volume and least body fatness. Third, those with the biggest torso volume and most body fatness with bigger width between armpits and shoulders. The distributional pattern analysis showed that men in their 30s tend to have increasingly higher stature but lower body weight and BMIs than in the past, implying that their body types are becoming close to those of men in their 20s.

• The Journal of Korean Academy of Prosthodontics
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• v.29 no.1
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• pp.73-89
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• 1991

Impression ragistration is an improtant and difficult phase of prosthodontic treatment procedures and a tray of appropriate size and shape is essential to obtain the accurate impression. Particularly, in edentulous patients, the size and forms of their residual alveolar ridges are different from one another. Therefore, in this study, various measurements were taken on the edentulous models. And the measurements were analyzed and compared with one another. The results were as follows ; 1. The mean of denture bearing area was $32.86cm^2$ in the upper jaws, $24.20cm^2$ in the lower jaws and the variation of denture bearing area was greater in the upper than in the lower jaws and in males than in females. 2. The mean of A-P(anteroposterior) ridge length was 48.72mm in the upper jaws, 53.05mm in the lower jaws and that of males was longer than that of females. 3. The mean of most posterior ridge width was 47.23mm in the upper jaws, 58.03mm in the lower jaws and the difference of that between males and females was least in both jaws. 4. In the upper jaws, the mean of ridge width was 29.66mm on anterior 1/4, 42.79mm on middle, 48.95mm on posterior 1/4 line and the mean of palatal height was 4.56mm on anterior 1/4, 10.01mm on middle, 10.84mm on posterior 1/4 line. 5. In the lower jaws, the mean of ridge width was 33.24mm on anterior 1/4, 50.19mm on middle, 59.16mm on posterior 1/4 line and the mean of lingual ridge height was 5.49mm on anterior 1/4, 9.16mm on middle, 16.72mm on posterior 1/4 line. 6. The correlation coefficient(=r) between denture bearing area and A-P ridge length was 0.83 in the upper jaws and 0.75 in the lower jaws. The corelation between denture bearing area and AP ridge length was statistically significant, but, between denture bearing area and A-P ridge length and between A-P ridge length and the most posterior ridge width was not statistically significant in both jaws. 7. Alveolar ridge forms were classified into three(ovoid, "u" shape, and "v"shape) categories. In the upper jaws, ovoid was 66%, "u" shape was 24%, and "v" shape was 10%, in the lower jaws, ovoid was 66.7%, "u" shape was 20%, and "v" shape was 13.3%.

• The Korean Journal of Quaternary Research
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• v.8 no.1
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• pp.33-42
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• 1994

The study area is filled up by alluvium which can be classified into lower and upper beds by the facies of deposits and their degree of weathering. The lower bed is not of marine but of fluvial. The upper bed is mainly composed of clay and silt or fine sand beds col-ored dark or dark gray which are of neritic or brackish yielding mollusca fossils. The oyster(Crassostrea ariakensis) obstained from the depth of 3m below the present sea level in the upper bed was dated at 4,100 110Y.B.P. and the veneridae(Meretrix lamarck) 1m height above the present delta plain in the old sand bar was dated at 1,700 85Y,B,P. It is therfore concluded that the study area a small kern col of terrestri-al basin prior to postglacial age had experienced the Holocene transgression. Consequently the study area is considered to have been progressively formed under neritic or brackish circumstance before 1,700Y.B.P.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1996.11a
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• pp.144-149
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• 1996

In this paper, the clamping type forging of helical gears has been investigated. Clamping type forging is an operation in which the product is constrained to extrude sideways through an orifice in the container wall. Punch is cylindrical shaped. The punch compresses a cylindrical billet placed in a die insert. As a consequence the material flows in a direction perpendicular to that of punch movement. The forging has been analysed by using the upper-bound method. A kinematically admissible velocity field has been developed, wherein, an involute curve has been introduced to represent tooth profile of the gear. Numerical calculations have been carried out to investigate the effects of various parameters, such as module, number of teeth, helix angle, friction factor and initial height of billet on the forging of helical gears.

• Proceedings of the Korean Geotechical Society Conference
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• 2002.10a
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• pp.689-696
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• 2002

The behavior of two-level soil-reinforced segmental retaining wall was examined using the finite element analysis. A number of different case was analyzed by varying the reinforcement length and the offset distance between the upper and lower wall. The results indicate that the interaction between the upper and lower walls can be neglected the upper wall is located beyond the distance of the lower wall height. A so found is that for moderate offset distances, the interaction between the two walls generally is limited to the external stability of the wall. Implication of the findings are discussed

• Journal of the Korean Society for Precision Engineering
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• v.12 no.11
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• pp.91-97
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• 1995

In this study, a deformation model for the regular polygonal-shaped tubes from hollow-cylindrical billets is proposed and a kinematically admissible velocity field is obtained from this deformation model. The final stage upper-bound extrusion load and the average extruded length are determined by minimizing the total power consumption with respect to chosen parameters. Experiments have been carried out with hard solder billets at room temperature. The theoretical predictions of the extrusion load are in good agreements with the experimental results and there is generally reasonable agreement in average extruded height between theory and experiment.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2010.04a
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• pp.671-672
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• 2010

• The korean journal of orthodontics
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• v.23 no.4 s.43
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• pp.455-474
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• 1993

Degenerative joint disease(DJD) has hun known as one of the diseases which affect the middleor old-aged people. But as orthodontists are getting interested in the adult orthodontics, it is not rare for them to meet the open-bite patients with the TMJ DJD in their clinics. The purpose of this article is to investigate the cephalometric characteristics of the open-bite cases with TMJ DJD. Twelve TMJ DJD patients($15.1\~39.5$ years old) were selected from the patients who visited Department of Orthodontics, Seoul National University Hospital. Cephalograms were taken and means from 60 measurements were compared by t-test with those of the fifty four healthy adults($20.0\~26.7$ years old) who have normal occlusion and TMJ. In this study male and female are compared respectively, for in the normal samples 26 measurements showed significant differences between the male and the female. The results and conclusions axe as follows: 1 In DJD group, ANB and Angle of convexity decreased, which means the retruding of the mandible. The interincisal angle was smaller than that of the normal group. The means of the overbite were -2.1mm in male and -3.0mm in female, and the means of the overjet were 5.6mm in male and 6.7mm in female. The profile was similar to that of Angle's Class II div.1 open-bite. 2. SN-GoMe and FMA increased in DJD but SN-PP and FH-PP did not show any significant difference. In TMJ DJD open-bite cases, the bony structure lower than the palatal plane seemed to play an important role in developing open-bite. 3. In DJD group, PH-ArGo, SArGo and Y-sxis angle increased significantly, but genial angle showed no significant difference. The means of hか were 50.1mm in male and 40.2mm in female, which were significantly smaller than those of the normal(56.5mm in male, 50.9mm in female). These findings seemed to indicate the posterior rotation of mandible resulted from the shortening of the ramus height. 4. Anterior faical height(AFH), upper anterior facial height(UAFH) and lower anterior facial height (LAEH) of DJD showed no significant increase as compared with those of the noraml group. There was no significant difference in the ratio of upper anterior facial height to lower anterior facial height(UAFH/LAFH). But, lower posterior facial height(LPFH) was significantly smaller than that of the normal group. 5. It was thought that the peculiar profile of the TMJ DJD open-bite was resulted from the posterior rotation of mandible as the ramus became short following the degerative destruction of of the condylar head and neck.