• 대한기계학회논문집A
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• 제37권8호
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• pp.975-981
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• 2013

강건 최적화 기법은 설계 초기 단계부터 설계변수의 변동이 목적함수에 미치는 효과를 최소화할 수 있는 유일한 방법이다. 강건 최적화의 정식화를 위해서는 분산을 정확히 예측하고 확률제한조건을 정식화하는 것이 가장 중요한 과정이 된다. 분산 및 확률제한조건을 예측하고 정식화하기 위한 방법으로 공정능력지수 및 식스시그마 기법과 같은 여러 가지 방법이 적용되고 있으나, 실제 공정에서 널리 적용되는 불량률을 이용한 확률제한조건 처리 기법에 대한 연구는 아직까지 전무한 상태이다. 본 연구에서는 자동차 로워암의 무게와 최대응력의 평균과 표준편차에 대한 설계영역을 탐색하고, 이후 로워암의 강건 최적화를 수행하였다. 변동을 예측하기 위한 표준편차의 계산은 2 차 테일러 전개를 통해 수치적인 정확도를 기하였다. 강건 최적화는 설계변수의 불연속성을 고려하기 위하여 최적화 과정에서 미분 정보를 적용하지 않은 심플렉스 알고리즘을 적용하였다.

• 대한통합의학회지
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• 제11권4호
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• pp.41-50
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• 2023

Purpose : The aim of study was to determine the effect of lower trapezius muscle strengthening exercises on the height of rounded shoulder posture and muscle activity in patients with rounded shoulder posture. Methods : Thirty-one subjects with rounded shoulders were selected and assigned, with the use of a random number table, to an experimental group (EG, n=16) that received resistance exercises of the trapezius (lower) muscles or a control group (CG, n=15) that received isometric exercises of the lower trapezius muscles. In the EG, with the subject in a prone position, both arms were abducted at the angles suggested for each posture (145 °, 45 ° abduction), with the hands holding dumbbells to assume a functional posture. The CG performed only isometric exercises without dumbbells in the same conditions. At the start signal, with the thumb raised, the arm was raised to the level of the ear. Both groups were assessed by the height of the rounded shoulder posture (RSP) and muscle activity (EMG). The intervention was performed three times a week. Results : The RSP significantly decreased during the intervention period in both the EG and CG (p<.05), and a significant difference was determined between the RSP of the two groups (p<.05). In the EG, the EMG significantly increased during the intervention period (p<.05), but the CG did not show any significant increase (p>.05). The final EMG was significantly higher in the EG than in the CG (p<.05). Conclusion : Both the EG and CG showed positive improvement in rounded shoulder posture during the intervention period. In particular, lower trapezius resistance exercise appears to reduce shoulder height and positively affects the activity of muscles around the shoulder.

• The Journal of Korean Physical Therapy
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• 제28권2호
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• pp.88-94
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• 2016

Purpose: The purpose of this study was to compare therapeutic climbing exercise and general isometric exercise in patients with shoulder impingement syndrome. Methods: Among 20 adults, study subjects were arbitrarily classified into an experimental group of 10 and a control group of 10. The control group performed general isometric exercise (ISE) and the experimental group performed therapeutic climbing exercise (TC) (3 sets, 3 times per week for 8 weeks). To evaluate the effects of exercise, subjects were evaluated using a Disabilities of the arm, shoulder and hand score (DASH), a goniometer for range of motion, and shoulder activity measured serratus anterior, upper trapezius, and lower trapezius. Independent and paired t-test were used for comparison of the effect between groups. Results: DASH scores showed a significant decrease in both groups after 8 weeks of treatment (p<0.001) and significant difference was observed between the TC groups (p<0.01). Flexion and abduction were significantly increased after 8 weeks of treatment in the ISE group (p<0.001) and flexion, abduction, external and internal rotation were significantly increased after 8 weeks of treatment in the TC group (p<0.001). Serratus anterior and lower trapezius activity were significantly increased after 8 weeks of treatment (p<0.001) and upper trapezius activity was not significantly increased after 8 weeks of treatment in the ISE group (p>0.05). Serratus anterior, lower trapezius, and upper trapezius activity were significantly increased after 8 weeks of treatment in the TC group (p<0.001). Conclusion: Scapular stabilizing exercise using a therapeutic climbing exercise increases range of motion and decreases DASH, and increases activity of shoulder muscles in patients with impingement syndrome.

• 대한안전경영과학회지
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• 제8권4호
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• pp.13-23
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• 2006

Grip strength provides a quick and objective index of the functional integrity of the upper extremities. It is widely used as an assessment measure in physical and rehabilitation medicine. In this study, maximum voluntary grip strength of 20 college students wearing 5 different gloves were measured using Jamar hand dynamometer. The results show that maximum voluntary grip strength was generally reduced when wearing gloves as compared to bare-handed. More specifically, the grip strength was highest when wearing PVC coated glove or bare-handed and getting lowered as wrist band, rubber, leather, and cotton glove in these order. Depending on the measuring posture of grip strength, shoulder height with arm extended forward was higher than the elbow was flexed 90 degree. Moreover, subjects' demographic factors and hand dimensions were not closely related to the grip strength. It is thus recommended that the proper glove should be provided to reduce the negative consequences including dropping a tool, poorer control of a tool. lower quality work, and increased muscle fatigue and in turn to increase the user safety and satisfaction.

• 대한기계학회논문집A
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• 제30권9호
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• pp.1142-1147
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• 2006

A practical method for reducing the number of spot welds in automotive structures considering fatigue crack initiation life is suggested. At first, an influence index for the durability and the fatigue life of a spot weld itself is defined and then taken as the main effect of the DOE analysis. Spot welds that can be removed without serious reduction of durability through numerical experiments are selected by the results of DOE. The proposed method was applied to the shock tower and LCA(lower control arm) structure of a vehicle, which are important components in durability-related point of view.

• 대한지역사회영양학회지
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• 제2권3호
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• pp.366-375
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• 1997

This study was conducted to evaluate the effectiveness and preferences of supplementary drinks for very old subjects who are likely to be malnourished. Twenty- five elderly subjects were divided into two groups. The supplemented group(N=15) received 500mls of nutrient supplement(New Care) two times daily for 4 weeks. This resulted in a significant increase in the total calories, protein, minerals and vitamins. Nutritional status was assessed both anthropometrically and biochemically, before and after the study period. A significant improvement in mid arm circumference, triceps skinfold thickness and serum albumin were observed in the supplemented group but not in the control group. There is a possibility that most of the elderly were in an anemic state at the beginning of the study since their mean hematologic parameters were within the lower normal range while their mean serum osmolarities was slightly higher than normal, . Although mean serum hemoglobin and hematocrit were not increased significantly, th percentage of the recovery rate from anemia in the supplemented group was higher than in the control group. Total lymphocyte count also showed similar tendency. Sensory evaluation of nutritional supplementary drinks were relatively good and the elderly showed great interest in nutrient supplements. This study suggests that a nutritional status of poorly nourished elderly subjects can be improved by providing them with nutritional supplementations.

• 한국통신학회논문지
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• 제34권4B호
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• pp.360-367
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• 2009

본 논문에서는 MAC-SAP (Medium Access Control-Service Access Point)에서 하향 100Mbps 이상의 처리 속도를 요구하는 IEEE 802.11n MAC의 구현을 위한 새로운 방안을 제안하고, 이를 이용해 설계된 MAC의 구조를 제시한다. 제안된 방식을 이용하면, 기존에 MAC 프로토콜의 검증 및 네트워크 기반 시뮬레이션 과정과 소프트웨어 및 하드웨어의 설계 및 검증 과정이 분리되어 진행되던 방식과는 다르게 하나의 통합된 코드를 사용하여 네트워크 시뮬레이션과 시스템의 설계가 밀접한 연관성을 가질 수 있다. 제안된 방식을 통해 구현된 IEEE 802.11n MAC은 상위계층 MAC과 하위계층 MAC의 두 부분으로 구성되며, 각각은 표준에 새롭게 추가된 기능의 효율성을 높일 수 있게 그 기능을 구분하여 각각 소프트웨어와 하드웨어로 설계되었다. 설계된 MAC은 ARM 기반의 FPGA 보드를 통해 검증되었다.

• PNF and Movement
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• 제17권1호
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• pp.119-127
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• 2019

Purpose: The purpose of this study is to show the effect of elastic band on balance and functional ability in chronic stroke patients living in community. Methods: The subjects who participated in the study were 9 patients with chronic stroke. One of them gave up during the study, finally 8 patients performed. The intervention was conducted once a week for 10 weeks. In this study functional reach test (FRT), timed up and go test (TUG), Tinetti performance oriented mobility assessment (Tinetti-POMA) were measured for balance. The coordination training of arms and legs using the elastic band was performed in three positions as supine, side lying, sitting. One arm performed flexion-adduction- external rotation with elbow flexion pattern and the opposite side(diagonal) leg was performed flexion-adduction-external rotation with knee flexion pattern, the other arm's pattern was extension-abduction-internal rotation with elbow extension and the opposite side (diagonal) leg was in extension-abduction-internal rotation with knee extension pattern. The training was performed in each position for 15 minutes in per position. The participants had a five minute break after each training. Results: The results are as follows. FRT and Tinetti-POMA showed significant increase statistically in each position. The TUG showed significant decrease statistically in each position. Conclusion: Even though the coordination training with elastic band had performed once a week, it showed positive effects on balance in chronic stroke patients. Therefore, if we can suggest the appropriate frequencies of coordination training of arms and legs using the elastic band, it can be a method to improve daily life and life quality to patients with chronic stroke.

• 대한방사선기술학회지:방사선기술과학
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• 제46권5호
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• pp.395-399
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• 2023

The knee arthritis patients are generally performed standing position radiography. However, patients with pain caused by degenerative diseases or injuries in the knee have difficulty maintaining a standing position. Therefore, this study aims to develop a knee joint standing weight bearing projection assist device to solve these problems when patients undergo knee radiography due to various diseases. The design of the knee joint weight-bearing radiography assist device is carried out with 3D design and drawing production to secure basic data, electric support and frame manufacture. A fixed device for maintaining the patient's knee standing weight-bearing projection, an electric digital height device, a digital protractor, and a safety device were designed. The arm support is made of PVC with a cushion to relieve the impact and make it easier to remove debris. The digital electric device can be moved up and down according to the patient's height, and a remote control is attached. The safety device is made to be adjustable in size by attaching metal hooks on both sides of the frame and to shield the scrotum. A digital protractor was attached to the side frame to set the desired knee angle. When a self-made assist device was used to perform a knee joint standing weight bearing projection, it helped maintain arm support and lower extremities position. In addition, the height could be adjusted using an assist device during standing projections, which helped the patient maintain the position.

• Journal of Nutrition and Health
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• 제35권1호
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• pp.90-101
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• 2002

This study was undertaken to investigate the nutrient intake, dietary behavior, perception of body image and iron deficiency of high school adolescent girls. The subjects were 463 high school girls in Inchon. This cross-sectional survey was conducted by questionnaires and data were analysed by SAS program. Nutrient intakes collected from 3 day-retails were analyzed by the Computer Aided Nutritional Analysis Program. The following anthropometric measurements were made on all participants height, weight, body fat (%), skinfold thirkness, subscapular skinfold thickness, mid-upper arm circumference and waist-hip circumference. Blood samples were obtained and analyzed for iron nutritional status. The mean obesity index of rural students were highest among students. However, over 18% of the urban and rural students belonged to the low-weight group. Proportions of skipping meals were most high in urban vocational students and the main reason was lack of time for meal. Most nutrient intakes of the students were below the RDA, in particular calcium, iron, vitamin A and vitamin B$_2$. Most of the students were concerned with body image and weight control. Also they were not satisfied with their body image. The mean fell hemoglobin and transferrin saturation of rural students were lowest among students. The total binding capacity of urban vocational student\ulcorner were Invest among students. Prevalence of iron deficiency was most high in urban general students when judged by Hb, MCV and serum ferritin. In conclusion, this study indicates that nutrient intake in the female high school students was considerably lower than RDA. They should also be notified that severe weight control is very harmful for health. And they had lower self -satisfaction for their body image and undesirable flood habits. Therefore, prefer nutrition education is required to maintain desirable flood habits and improve their iron status in female high school students.