• Transactions of Materials Processing
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• v.8 no.3
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• pp.295-295
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• 1999

In the present study, the corrosion behavior of AZ91D as-cast alloy was investigated form the viewpoint of the distribution aspect of precipitate ($Mg_{17}Al_{12}$) and the variation of Al concentration in the Mg-rich matrix. The dendrite arm spacing (DAS) of an as-cast specimen was measured as a function of degree which describes the distribution aspect of the precipitate, and the salt spray test was conducted for various grain-sired specimens fur 20 days. The dendrite arm spacing increased as the grain size increased to about 150㎛, but a constant value is indicated when the grain size exceeds that range. Although the relationship between the corrosion rate and grain size is of a nonlinear type, the linear trend between the corrosion rate and the dendrite arm spacing is maintained for the overall range of dendrite arm spacing. Since the precipitate in the as-cast alloy is discontinuously distributed, this linear relationship means that the variation of Al-solute concentration in the Mg-rich matrix has a more potent effect than the protective action of the precipitate on the corrosion behavior of an as-cast alloy.

• Journal of the Korean Society of Costume
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• v.54 no.1
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• pp.69-81
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• 2004

The purpose of this study was to find out apparel fit satisfaction according to item(jacket, pants, skirt) by body perception and body satisfaction. This research was done by a survey method. Descriptive Statistics, Pearson's Correlation, Crosstabs were used for data analysis. The results of this study are as follows. 1) Correlation between body perception and body satisfaction : The subjects were less satisfied with larger or thicker girth of upper body. The subjects were less satisfied with thicker upper arm, lower arm, waist and lower abdomen. The subjects were more satisfied with taller height. The subjects were less satisfied with larger or thicker girth of lower body. The subjects were less satisfied with thicker hips. thighs, calves, ankles, and longer crotch length. However, they were more satisfied with longer legs. 2) Apparel fit by body perception and body satisfaction: The subjects who were less satisfied with thicker upper arm, waist, thighs and wider hips were less satisfied with the upper arm area, waist area. hip area of jacket. The subjects who were more satisfied with longer arms were more satisfied with the sleeve length of jacket. The subjects who were less satisfied with wider shoulder width were less satisfied with the upper back width of jacket. It means the shoulder width affected more the upper back width of jacket than shoulder width of jacket. The subjects who were less satisfied with wider hips were less satisfied with the hip area of pants and skirt. The subjects who were less satisfied with thicker thighs were less satisfied with the thigh area and the hip area of pants and skirt. The subjects who were less satisfied with longer crotch length were less satisfied with the crotch length of pants. 3) Difference between actual body and perceived body by Rohrer Index: Rohrer Index 109 calculated by average of the ideal height(165.83cm) and weight(49.78kg) of the subjects ranged in thin body type(below 120). The subjects tended to perceived their bodies fatter than their actual bodies. Also, the subjects tended to perceived their lower bodies fatter than upper bodies.

• Journal of Chest Surgery
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• v.12 no.3
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• pp.174-182
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• 1979

This is a report on four cases of successful surgical correction of coarctation of the aorta [COA] in Department of the Thoracic & Cardiovascular Surgery, Hanyang University Hospital. The first case was a postductal type of coarctation of the aorta associated with Patent ductus arteriosus [PDA], Persistent left superior vena cava [LSVC] and richly developed collateral circulation. Blood pressure was measured to be hypertensive at the arm, but hypotensive at the legs. The coarctation of the aorta was corrected with following procedure: Partial resection of the aortic wall with diaphragmatic structure lust above and below the coarctating line of the aorta, and then the defect of the aortic wall was closed by lateral aortographic suture. PDA was closed by ligation procedure. The second case a preductal type of coarctation of the aorta associated with PDA, LSVC, ventricular septal defect [VSD] and poorly developed collateral circulation. Normal blood pressure was measured at the arm, but hypotension was observed at the legs. Correction of coarctation of the aorta was performed under the establishment of tube bypass because of poor collateral circulation. After resection of coarctating short segment, end to end anastomosis was performed without any tension. PDA was closed by division procedure. Simple suture closure of VSD was performed by open heart surgery two weeks after correction of COA. The third case was a long segment COA without any other anomaly. Blood pressure was measured to be hypertensive at the arm, but hypotensive at the legs. Vascular prosthesis was performed using Teflon graft tube after resecting coarctating long segment [6.5 cm] of the aorta. The fourth case was a long segment COA associated with aortic insufficiency and richly developed collateral circulation. Normal blood pressure was measured at the arm, but hypotension was observed at the legs. Vascular prosthesis was performed using Teflon graft tube after resecting coarctating long segment [6.0 cm] of the aorta. Both blood pressure and peripheral pulse on the arm and the legs returned to normal postoperatively in all patients.

• Journal of the Korean Institute of Intelligent Systems
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• v.17 no.6
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• pp.738-743
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• 2007

In this paper, a muscle motion sensing system and an artificial arm control system are studied. The artificial arm is for the people who lost one's forearm. The muscle motion sensing system detect the intention of motion from the upper arm's muscle. In sensing system we use flex sensors which is electrical resistance type sensor. The sensor is attached on the biceps brachii muscle and coracobrachialis muscle of the upper arm. We propose an algorithm to classify the one's intention of motions from the sensor signal. Using this algorithm, we extract the 4 motions which are flexion and extension of the forearm, pronation and supination of the arm. To verify the validity of the proposed algorithms we made experiments with two d.o.f. artificial arm. To reduce the control errors of the artificial arm we also proposed a fuzzy PID control algorithm which based on the errors and error rate.

• Korean Journal of Applied Biomechanics
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• v.16 no.2
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• pp.45-53
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• 2006

The purpose of this study was to analyze exercise related mechanical variables according to performance levels and Kumi-kata types in elite judo players (G1) and non-elite judo players, namely university players (G2). To achieve this purpose, three players in G1 whose main special skill was Morote-Seoinage and three university judo players(G2) was selected as comparative group. Then they were examined for distinguishing A and B types of Kumi-kata. Analyzed variables were the time required to show skills, knee degree, elbow degree. After analysing this study, conclusions were derived as follows. 1. In total necessary time of showing skills according to group of Kumi-kata type, G2 was longer than G1 in both A type (20.9%) and B type (23.7%). In necessary time of phase, in only 3P, G1 was shorter than G2 in A type (50%) and B type (75%). There was no difference in time required of 1P and 2P according to Kumi-kata type of group and in only 3P, B type was shorter than A type in both B type (75%) of G1 and B type (50%) of G2 2 There was no difference in elbow degree of offensive arm according to group of Kumi-kata type, however in A and B types, G1 could use skills by extending in kake phase, but G2 could use skills by bending. Elbow degree of offensive arm according to Kumi-kata type of group showed difference in E1. and F2 of G1. A and B types of G1 extended elbow degree in Kake phase, but G2 bent elbow degree so exercise program which could movable range extensively in Kake phase is needed.

• The Research Journal of the Costume Culture
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• v.25 no.5
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• pp.561-576
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• 2017

The purpose of this study was to classify the upper torso body types of obese Korean adult women using the 7th Korea National Anthropometric Study data and compare the body type differences according to three age groups: 20s~30s, 40s~50s, and 60s. A total of 548 adult women whose BMI was in the obese range of 25 or higher and whose age ranged from 20s to 60s were selected from the anthropometric database. Twenty-nine body measurements related to torso and arm areas important for torso and sleeve pattern development were chosen. Five drop values by differences between bust, waist, and hip circumferences were also chosen for analysis. The number of obese women increased with age. The results revealed seven factors according to the factor analysis and three obese body types based on the cluster analysis. Body type 1 (47.3% of obese women) was characterized by narrow shoulders, a small or medium torso, and a straight waist. Body type 2 (42.4% of obese women) was characterized by a defined waist and a larger lower torso than upper torso. Body type 3 (10.3% of obese women), the largest obese body type among the three types, was characterized by a large bust, large abdomen area, and long upper torso. Women in their 20s to 30s were most likely to have body type 2, women in their 40s to 50s were evenly distributed between body types 2 and 3, and women in their 60s were most likely to have body type 1.

• Transactions of the Society of Information Storage Systems
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• v.2 no.1
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• pp.21-25
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• 2006

The new multimedia information environment requires smaller optical data storage systems. However, one of the difficulties encountered in designing small form factor(SFF) optical pick-up is to emit the heat which is generated from laser diode(LD). Heat generated at the LD can reduce the optical performance of the system and the lifetime of LD. Therefore, it is important to include the thermal design in the design stage of SFF optical pick-up system for high performance and the longer lifetime of LD, and furthermore, to analyze the thermal characteristics of LD in detail micro heat transfer analysis is necessary. In the present study, micro heat transfer analysis was performed using the finite element method for the $28{\times}11{\times}2mm^3$ super slim swing-arm type optical pick-up actuator for Blu-ray disk. Two different materials were used for a swing-arm; a double layer polycarbonate/steel structure and a single aluminum structure.

• Journal of the Institute of Electronics and Information Engineers
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• v.51 no.10
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• pp.256-263
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• 2014

We have designed and made three kinds of FBG(Fiber Bragg Grating) Acoustic Transducer using Hopper type WDM on the use of recently developed FBG in Korea. The newly designed three kinds of FBG Acoustic Transducer using Hopper type WDM have an excellent merit of practical use with simple structure of sensors arm as well as the merit with existing fiber sensors. It was possible to detect sound waves in the range of 10 Hz to 18 kHz through the newly designed three kinds of FBG Acoustic Transducer and also, possible to detect its signal within the maximum range of 8.6 m by the use of most suitable resonance condition of the transducer. Especially, we can expect the utilization of low-frequency signal detection instead of existing acoustic sensor in the environment of electric noise and inferior condition. Furthermore, they can be developed as the high-sensibility and multi-point signal detection system through the sensor array system.

• Journal of the Korean Society for Precision Engineering
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• v.17 no.3
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• pp.68-75
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• 2000

The flexibility of a manipulator inevitably yields vibration at the end effector. In this work, position and vibration control for a flexible robot arm was studied using a separate voice coil type actuator to raise the accuracy and speed of end tip. A flexible robot arm with a tip mass is modeled as an Euler-Bernoulli beam. An $H_$\infty$$ controller is adapted to get a robust control against unmodeled higher-order mode vibration, output sensor noise, and etc. Simulations and experiments show that the modeling of the system is acceptable and robust vibration control is also achieved.

• Journal of KSNVE
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• v.10 no.2
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• pp.299-305
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• 2000

In this study, the characteristics of transmitted vibration on hand-arm system are examined when operating electric hand tools. Also through the correlation analysis between anthroponetric data and transmitted vibration, and comparison study with appropriate amount of work done based on the ISO criteriaa, the basic data for the ergonomic work design can be presented. The types of electric tools and works for the experiment are drill (general type and impact type), grinder, wire brush and steel to analyze the characteristics of transmitted vibrations, the amount of transmitted vibrations in X, Y and Z direction at tool(T), hand(H), wrist(W), and the joint between foream and upper arm(A) were measured at the frequency range of 6.3∼1000[HZ]. Also, the limit of human exposure to vibration, and the response of frequency were conducted.