• The Journal of Advanced Prosthodontics
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• 제10권5호
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• pp.381-387
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• 2018

PURPOSE. Cement-retained implant prostheses can lack proper retrievability during repair, and residual cement can cause peri-implantitis. The purpose of this in vitro study was to evaluate the influence of abutment height and convergence angle on the retrievability of cement-retained implant prostheses with lingual slots, known as retrievable cement-type slots (RCS). MATERIALS AND METHODS. We fabricated six types of titanium abutments (10 of each type) with two different heights (4 mm and 6 mm), three different convergence angles ($8^{\circ}$, $10^{\circ}$, and $12^{\circ}$), a sloped shoulder margin (0.6 mm depth), a rectangular shape ($6mm{\times}6.5mm$) with rounded edges, and a rectangular ledge ($2mm{\times}1mm$) for the RCS. One monolithic zirconia crown was fabricated for each abutment using a dental computer-aided design/computer-aided manufacturing system. The abutments and crowns were permanently cemented together with dual-curing resin cement, followed by 24 hours in demineralized water at room temperature. Using a custom-made device with a slot driver and torque gauge, we recorded the torque ($N{\cdot}cm$) required to remove the crowns. Statistical analysis was conducted using multiple regression analysis and Mann-Whitney U tests (${\alpha}=.05$). RESULTS. Removal torques significantly decreased as convergence angles increased. Multiple regression analysis showed no significant interaction between the abutment height and the convergence angle (Durbin-Watson ratio: 2.186). CONCLUSION. Within the limitations of this in vitro study, we suggest that the retrievability of cement-retained implant prostheses with RCS can be maintained by adjusting the abutment height and convergence angle, even when they are permanently cemented together.

• 디자인학연구
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• 제12권1호
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• pp.157-166
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• 1999

컴퓨터의 도입과 함께 VDT 증후군이라는 새로운 사회문제가 제기되고 있다. 다양한 체격의 사용자가 무리 없는 자세로 VDT작업을 수행하기 위해서는 인간공학적인 설계기준이 필요하다. 본 연구에서는 선 연구의 설계지침을 이용하여 설계 권장치수를 먼저 제시하였다. 이에 대찬 타당성 검증을 위해 사용자의 선호치수를 구하였고, 그것과 설계지침에 따른 차이를 분석하였다. 그리고 안락감과 신체불편도 평가를 통한 주관적 평가와 근전도(EMG)분석을 통한 객관적 평가를 사용하여 각 설계치수가 인체에 미치는 영향을 비교분석 하였다. 워크스테이션에서 중요한 키보드의 높이는 팔꿈치보다 높이가 낮다면 손과 손목에 영향을 미치고, 높으면 목과 어깨에 피로를 가져다준다. 본 연구 실험결과 한국인을 위한 키보드책상의 권장치수는 고정식일 때 660mm 조절식일 때 540-774mm를 추천한다. 그 외 설계권장치수는 본문에 제시하였으며 이와 같은 인간공학적 권장치수는 결론적으로 사용자의 신체에 맞게끔 조절범위를 제공하므로 설계 분야에 중요한 기초자료가 되리라본다.

• 한국의상디자인학회지
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• 제24권3호
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• pp.49-61
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• 2022

This study aims to provide upper body shape information by analyzing the measurement data of middle-aged women aged 50-69, including baby boomers, whose economic power and activity have improved compared to the previous generations. In order to provide accurate upper body shape information by analyzing the body type using the 8th Size Korea measurement data, body shapes were classified through factor and cluster analysis using 75 direct measurement items. Upper body type was classified according to the factors, and the associated characteristics were analyzed. As a result of the comparative analysis of the upper body measurements from the 4th to the 8th Size Korea measurement, it was found that in the height item, both the waist height and the hip height increased, making the overall height greater and the leg length longer. The body circumference items tended to increase, but were found to decrease significantly in the 8th Size Korea (2021) measurement. Middle-aged women were classified using five factors. Factor 1 was the upper body obesity factor, and Factor 2 was the trunk vertical factor. Factor 3 was the width of the back shoulder, Factor 4 was the vertical factor behind the back, and Factor 5 was the length factor of the front garment composition. Middle-aged women were classified into four body types through cluster analysis. Type 1 is relatively small and skinny, Type 2 has the most obese upper body and developed back shoulders, and Type 3 is skinny and has a long back and short front. In Type 4, the upper body was relatively long and the shoulders were narrow.

• 한국운동역학회지
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• 제29권2호
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• pp.121-128
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• 2019

Objective: The aim of this study was to examine the relation between swing phase and airborne phase of Tkatchev motion which was successfully performed with following motion by excellent middle and high school athletes in horizontal bar. Method: The subjects for this study were 8 male middle and high school top athletes. After their Tkatchev motions were filmed by two digital highspeed camcorders setting in 90 frames/sec at the 44th National Gymnastics against Cities and Provinces, the % lapse time lapse time of each instant, inferred maximum force acting on horizontal bar, and other kinematical variables were calculated through DLT method. After the relations among the % lapse times of each instants of downswing-start, downswing-finish, whipswing-finish, release, peak-height, and lapse time of regrasp, the relation among maximum force acting on bar, % lapse time, peak height, and the relation between % lapse time and release height were examined, the biomechanical timing characteristics of Tkatchev motion were as follows. Results: Firstly, it was revealed that the whole lapse time was $1.62{\pm}.06s$ and the correlation between the % lapse time of downswing-start and % lapse time of release was .819. Secondly, it was revealed that the pattern of COG path was shifted forwardly and tilted 11 clockwise from origin. Thirdly, it was revealed that maximum force acting on bar was inferred in $2,283{\pm}425N$ ($4.7{\pm}.6BW$) and the correlation between maximum force and peak height was r = .893. Lastly, it was revealed that the horizontal and vertical component of body COG velocity was $-2.14{\pm}.29m/s$, $2.70{\pm}.43m/s$ respectively, release height was $.49{\pm}.12m$, and shoulder angle was $139{\pm}5deg$, and that the later the % lapse time of release, the higher the release height (r = .935). Conclusion: It is desired that the gymnastic athletes should delay the downswing-start near the horizontal plane on $2^{nd}$ quadrant because the later the % lapse time of downswing, the higher the release height. After all the higher release height could ensure the athletes to regrasp the bar safely, the athletes should exercise to make downswing-start delay.

• 한국생활과학회지
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• 제10권4호
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• pp.379-390
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• 2001

The purpose of this study is to investigate the fitness according to drafting method of the block patterns for women in Korea. The major findings of this study are as follows: 1. According to comparative analysis of required measurements, two measurements of back length and bust girth are used in Proportional Drafting Method (Munhwa). In case of Compromise Drafting Methods are used across chest, across back, bust length, bust width, full length in front, across shoulder and shoulder length in addition to back length and bust girth. The type of Armstrong as a Short Measure Drafting Method uses 10 measurements for the drafting the bodice. 2. While Esmod block pattern arid Armstrong's block pattern are the lightest in full width and other widths. Rasara block pattern is the most ample. In Lee, Myung-hee's block pattern and Lee, Hyung-sook's block pattern, amounts of drooping are decided $3{\sim}4cm$, but drooping amounts of other block patterns are decided corresponding to real measurements. While cap height in Esmod and Armstrong's sleeve patterns are directly measured Armhole length of the block pattern, cap height of other sleeve patterns are used armhole depth and cap height length as well as armhole length. 3. When analyzing to indirect measurements, Esmod block pattern shows the least different between full length of block pattern and that of body form. Munhwa block pattern and Kim, Hyosook's block pattern are mostly same to body form back length. However all of the block patterns are sheller than body form length. In case of Suh, Wansuk's block pattern, across back and across chest are same size, but other block patterns show difference between across back and across chest. Most block patterns' neck width in front and bach bodice are almost same. Front neck width is generally bigger than back neck width in some cases.

• 대한인간공학회지
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• 제35권6호
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• pp.595-609
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• 2016

Objective: The purpose of this study was to develop and validate the guidelines for Medic Work Table (MWT) based on the anthropometric data of medical technologists. Background: Users' anthropometric data such as sitting height, sitting elbow height, knee height, and so on are significant factors for designing comfortable and useful furniture. Thus, many guidelines for different types of desks and chairs based on the users' anthropometric data have been suggested to many researchers. However, few researches have been conducted to provide design guidelines for MWT for blood collecting task. Medical technologists often use their upper extremities to perform blood collecting task with high repetitions. These repeated motions could be a critical factor in the prevalence rate of Work-related Musculoskeletal Disorders (WMSDs). Therefore, a study on ergonomic design of MWT would be essential in preventing the WMSDs and improving the quality of the working environment of medical technologists. Method: This study suggested design guidelines for ergonomic MWT by focusing on the heights of the upper side and underside, depths of the inside and outside, and width of MWT through anthropometric studies and literature reviews. Afterwards, a new MWT was made using the suggested design guidelines for this study. Five healthy medical technologists participated to evaluate the original MWT and new MWT. All participants took part in the range of motion (ROM) test, electromyography (EMG) muscle activity test, and usability test to validate the suggested guidelines in this study. EMG signals of related muscles (Flexor Carpi Ulnaris, Extensor Carpi Ulnaris, Deltoid Anterior, and Biceps Branchii) were recorded through the surface electromyography system from both the original MWT and the new MWT. The ROM test of the shoulder and elbow flexion was also assessed using motion sensors. Results: The newly designed MWT showed decreased ROMs of the shoulder and elbow up to 22% and 18% compared to the original MWT. The muscle activities in the new MWT also showed a decrease of 13% in Anterior Deltoid, 6% in Biceps Brachii, 5% in Flexor Carpi Ulnaris, and 8% in Extensor Carpi Ulnaris muscle groups, compared to the original MWT. In the usability test, the satisfaction score of the new MWT was also 56.1% higher than that of the original MWT. Conclusion: This study suggested guidelines for designing MWT and validating the guidelines through qualitative and quantitative analyses. The results of motion analysis, muscle activity, and usability tests demonstrated that the newly designed MWT may lead to less physical stress, less awkward posture, and better physical user interface. Application: The recommended guidelines of the MWT would be helpful information for designing an ergonomic MWT that reduces physical loads and improves the performance of many medical technologists.

• 복식
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• 제35권
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• pp.167-180
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• 1997

The purpose of this study was to find out some of the problems consumers have with ready to wear garments sizing and clothing satisfaction the following women's garments; sweaters T-shirts blouses jackets pants skirts one-piece jumpers and burberry(coats). For this study questionnaires were administered to female students in community college. Employing a sample of 166 students data were analyzed by Frequencies X2-test t-test ANOVA Factor Analysis and Regression. Major results of this study were summerized as follows: 1) Purchasing clothing subjects considered mainly bust circumference for T-shirts and blouse shoulder width for jackets and jumpers hip circumference for pants and skirts and length for sweaters(knit) one-piece and burberry(coats) as a reference of fitting sites. 2) In relation with dissatisfaction with apparel fit hip circumference of pants including jeans was found as the most unsatisfactory site. Besides subjects were dissatisfied with skirts sweaters one-piece jackets blouses burberry(coats) jumpers T-shirts in order. In relateion with height and body type were most dissatisfied with pants(jeans) 3) Factors related to clothing deprivation of ready-to-wear garment were identified as aethetics elements practical elements economic elements and fittness elements. Fittness elements were most dissatisfied factors with all items of garments except for skirts.

• 복식
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• 제26권
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• pp.279-288
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• 1995

The objective of the study was to provide fun-damental data on somatotype for elderly women by classifying the somatotype and analyzing the characteristics of their somatotype. The subjects were 368 women ages of 60∼84, they were measured direct anthropometry. In or-der to find out differences among the age groups, the 368 subjects were grouped into two age groups(Group 1 aged 60 to 69, Group 2 ; aged 70 to 84) Data were analyzed using Factor analysis, Cluster analysis, Duncan test and Analysis of variance. The results of this study were as follows. 1. The characteristics of Elderly women's somatotype were bending of the upper-torso, fat-ness of the waist and abdomen, drooping of the bust and shoulder and hip. In addition, height, girth, depth and width items were decreased in their sizes respectively. 2. Through the factor analysis, we extracted 5 factors from anthropometric measurements. Factor components were obesity, height, girth of the leg and arm, length of the upper-torso except the center front length, the center front length, we categorized by 4 clusters using 5 factor scores. And after the cluster analysis using 5 factor scores, 4 clusters were categorized. The characteristics of clusters were as follows. Type 1 was characterized by short, obesity type, and droopy bust. Type 2 was characterized by short and slender type, dropped bust, and bending somatotype from the lateral view. Type 3 was characterized by middle sized and straight somatotype from the lateral view. Type 4 was characterized by tall and obese type from the lateral view.

• 한국생활과학회지
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• 제12권5호
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• pp.787-795
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• 2003

This research studied several somatotypes for children's upper bodies in order to suggest the basic data of bodice patterns of children's clothing. By extracting the component factors from the children's bodices, they were classified into several somatotypes to recognize an individual body type. Three hundred and fifty eight children's wears were estimated as research objects to analyze their somatotypes for the 44 items representing upper bodies through anthropometric measurement and photometric measurement. The results are as follows : 1. Seven factors were extracted as a result of factor analysis. 2. Data were classified into three types as a result of cluster analysis : Type 1 was characterized as low fat body, small skeleton size, and forward belly ; type 2 as high fat body, normal hight, backward shoulder, and the lowered shoulders ; type 3 as medium fat body, tall height, somewhat crouching back, and the rising shoulders. 3. As a results of the discrimination analysis for the three types, the highly discriminated items were height, width of bosom, front center length. weight, width of waist or the length of waist. One could discriminate one's own body type by obtaining the classification function from these five items.

• 소성∙가공
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• 제16권6호
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• pp.457-462
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• 2007

The drawbeads, which are used for controlling the flow of the sheet into die cavity by imposing the tension and for preventing the forming defects like wrinkling, springback, etc. during the sheet forming process, affect the formability strongly because of the differences in the restraint and opening forces according to the drawbead shapes and dimensions. In this study, the experimental device enabling to measure the drawbead restraining and opening forces is manufactured and the drawing forces of circular, square, and step drawbeads are measured. The drawbead restraining and opening forces of a circular drawbead are increased as its drawbead height is increased. Similarly, those of a square drawbead are increased as its height is increased and shoulder radii decreased. The drawbead forces obtained from the experiment were compared with those calculated in the numerical simulation of stamping process of automotive fender. Good agreement was found so that the experimental measurements can be used in the simulation of auto-body stamping process.