• 한국해양공학회지
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• 제33권1호
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• pp.33-41
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• 2019

Estimating fatigue damage is a very important issue in the design of ships. The springing and whipping response, which is the hydro-elastic response of the ship, can increase the fatigue damage of the ship. So, these phenomena should be considered in the design stage. However, the current studies on the the application of springing and whipping responses at the design stage are not sufficient. So, in this study, a prediction method was developed using fluid-structural interaction analysis to assess of the fatigue damage induced by springing and whipping. The stress transfer function (Stress RAO) was obtained by using the 3D FE model in the frequency domain, and the fatigue damage, including linear springing, was estimated by using the wide band damage model. We also used the 1D beam model to develop a method to estimate the fatigue damage, including nonlinear springing and whipping by the vertical bending moment in the short-term sea state. This method can be applied to structural members where fatigue strength is weak to vertical bending moments, such as longitudinal stiffeners. The methodology we developed was applied to 325K VLOC, and we analyzed the effect of the springing and whipping phenomena on the existing design.

• Physical Therapy Rehabilitation Science
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• 제13권1호
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• pp.53-70
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• 2024

Background: The conventional deadlift is a popular exercise for enhancing trunk, core, and lower extremity strength. However, its use in sports medicine is constrained by concerns of lumbar injuries, despite evidence supporting its safety and rehabilitative benefits. To optimize muscle activation using resistive bands in variable resistance therapy, we explored their feasibility in the deadlift. Design: Comparative experimental design Methods: Surface electromyography recorded muscle activity in the trunk and lower extremities during lifting, with normalization to the isometric Floor Lift using Maximal Voluntary Contraction. Kinematics were measured using inclinometer sensors to track hip and trunk sagittal plane angles. To prevent fatigue, each subject only used one of the three pairs of bands employed in the study. Results: Our study involved 45 healthy subjects (mean age: 30.4 ± 6.3 years) with similar baseline characteristics, except for years of lifting and strength-to-years-of-lifting ratio. Various resistance band groups exhibited significantly higher muscle activity than conventional deadlifts during different phases. The minimal resistance band group had notably higher muscle activity in the trunk, core, and lower extremity muscles, particularly in the end phase. The moderate resistance band group showed increased muscle activity in the mid-and end-phases. The maximum resistance band group demonstrated greater muscle activity in specific muscles during the early phase and overall higher activity in all trunk and lower extremity muscles in the mid and end phases of the deadlift (p<0.05). Conclusion: Our findings provide valuable insights into muscle activation with various resistance bands during deadlift exercise in clinical and gym settings. There appears to be a dose-response relationship between increased resistance bandwidth, external load, myoelectric activation, and range.

• 한국전산구조공학회논문집
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• 제20권4호
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• pp.501-507
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• 2007

본 연구의 전편에서는 이동최소제곱 유한차분법을 이용한 고체역학문제의 정식화 과정이 소개되었다. 후편에서는 수치예제를 통해 이동최소제곱 유한차분법의 정확성, 강건성, 효율성을 검증했다. 탄성론 문제의 해석을 통해 개발된 해석기법의 우수한 수렴률을 확인했다. 탄성균열문제에 적용하여 간편한 불연속면 모델링이 가능하고, 적응적 절점배치를 통해 특이 응력해를 정확하고 효율적으로 계산할 수 있음을 보였다. 국소화 밴드문제 해석결과를 통해 변위나 응력이 급격하게 변화하는 특수문제에 대한 정확성과 효율성을 확인했으며, 본 해석기법이 다양한 특수 공학적 문제로 확장될 수 있을 것으로 기대된다.

• 패션비즈니스
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• 제24권3호
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• pp.17-29
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• 2020

This study aimed to produce fiber stretch sensors for smart soccer socks to prevent injuries during training. A sensor was manufactured with stretchable fabric and tested to ensure convenience during training. In order to manufacture the fiber stretch sensor, a CNT dispersion solution was applied to an e-band and elastic polyester fabric, and the performance of the sensors was evaluated by a tensile test. Performance evaluation showed that both of the tested fabrics are excellent for this purpose. Both sensors were attached to socks to create prototype wearable devices, and an experiment was conducted to determine whether a resistance change accompanying relaxation and contraction of the gastrocnemius muscle could be detected. In order to accurately evaluate performance as a sensor, the fabric was stretched 20 times at low speeds of 1 Hz and 0.5 Hz. A change in resistance due to tension was observed, with both the E-band and the stretchable poly fabric showing high sensitivity and high reproducibility. Both can be used as relaxation/contraction sensors. Smart soccer socks were made using the two materials, and an evaluation was conducted. Tensile tests were done on the smart soccer socks; the tests were done 20 times per sock, and the sensor showed a stable resistance change between 30 and 40 ohms depending on the tension of the sensor. As a result, we confirmed that smart soccer socks with stretch sensors made of E-bands can measure changes in the gastrocnemius muscle.

• 패션비즈니스
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• 제12권3호
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• pp.116-135
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• 2008

To investigate the actual distribution condition and clothing construction factors of the working clothes supplied to the Changwon national industrial complex, 5 major companies in machinery, automotive, industrial engineering, shipbuilding and rolling stock in the industrial complex located in Gyeongsangnam-Do were selected. The questionnaire designed for the research consisted of working clothes distribution policies in manufacturing industry and the actual conditions of the design facts, repair and maintenance of the working clothes, etc. The analysis of the clothing construction factors of the working clothes provided by 5 respondent companies were conducted in parallel. The results derived from the study were as follows: The basic types of working clothes were the blouson jacket and straight pants; safety equipments for manufacture were safety helmets, gloves, snickers, goggles, masks, ear caps, wristlets, leggings, apron, etc. The size-charts adopted by the participant companies were the small-medium-large and cm/inch measurement size systems. To solve wearer's dissatisfaction with the garment fit, certain clothing construction factors were used, e.g. strap bands and the elastic band on a waist band. The types of fabrics used for the working clothes were mainly polyester/cotton and polyester/rayon blended ones. Moreover, to provide with more air permeability to wearers, the warp knit material was used to construct the lining and the armpit or back bodice slits. Lock, two-thread chain, safety, overedge stitches were applied with flat, lap felled, French, superimposed, lapped, bound and edge finishing seams to construct the working clothes selected.

• 한국지진공학회논문집
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• 제24권1호
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• pp.49-57
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• 2020

In this study earthquake records were collected for rock conditions that do not reflect seismic amplification by soil from global earthquake databases such as PEER, USGS, and ESMD. The collected earthquake records were classified and analyzed based on the magnitude and distance of earthquakes. Based on the analyzed earthquakes, the design response spectrum shape, effective ground acceleration, and amplification ratios for each period band are presented. In addition, based on the analyzed data, the story shear force for 5F, 10F, 15F, and 20F were derived through an analysis of the elastic time history for multi-DOF structures. The results from analyzing the rock earthquake record show that the seismic load tends to be amplified greatly in the short period region, which is similar to results observed from the Gyeongju and Pohang earthquakes. In addition, the results of the multi-DOF structure analysis show that existing seismic design criteria can be underestimated and designed in the high-order mode of short- and medium-long cycle structures.

• 근관절건강학회지
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• 제13권1호
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• pp.7-19
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• 2006

Falls are a major sources of death and injury in elderly people. Aged-related changes in the physiological systems which contribute to the maintenance of balance are well documented in older adults. These changes coupled with age-related changes in muscle and bone are likely to contribute to an increased risk of falls in this population. Regular exercise may be one way of preventing falls and fall-related fractures. However, the optimal exercise prescription to prevent falls has not yet been defined. On the literature review of exercise intervention for fall prevention in the elderly, exercise appeared to be a useful tool in fall prevention by improving fall risk factors. The optimum exercise prescription; moderate intensity frequency of 3-4 times per week, duration of 30-60minutes can contribute to decreased hazards and number of fall. Fall prevention protocol should include safety, falling effect, enjoyment, and easiness to follow for older people. Effective exercise programs suggested for fall prevention were such as weight-bearing exercise, resistance exercise, lower muscle strength with elastic band, swiss ball exercise walking, tai chi, and yoga.

• 복식문화연구
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• 제7권2호
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• pp.289-303
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• 1999

This study aimed to provide basic data for designing adaptive dresses for the disabled elderly. The procedure of this study consisted of 3 parts ; 1. the survey of 205 nursing-care providers who take care of the disabled elderly, 2. the market survey of dadptive dresses for the disabled elderly, 3. wearing-tests of those adaptive dresses which are in the market. The results are as follows ; 1. The most popular style for the disabled elderly in nursing facilities was non-collar, regular pajamas. And the most favorite design was a pajama\`s style which has no collar but has a round neckline, front opening and 7/10 length shirt\`s sleeves, with pants of an elastic band waist. And the most desirable fabric was a physiologically comfortable one. 2. The system of adaptive dress sizes for the Korean elderly consisted of 85, 95, 105 ㎝, while that for the japanese elderly was divided into F/S/M/L/LL according to gender. 3. In the case of a pajama\`s style. it is necessary for the elderly men in the facilities need bigger sizes for their jump suits. When we tested the adaptive dresses for the elderly in the nursing facilities, in the case of a pajama\`s style, it was most difficult for us to pull pants over around the buttocks. In the case of jump suits, it was most difficult for us to dress and undress the adaptive dresses around the chest.

• 기본간호학회지
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• 제15권4호
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• pp.457-466
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• 2008

Purpose: The purpose of this study was to determine the effects of low intensity exercise program with telephone coaching on the physical fitness of elderly people who are receiving home visiting nursing care. Method: This study was conducted using a non-equivalent control group pretest-posttest design. The participants were 61 elders. Elders (34) in the experimental group performed low intensity exercise and of these 16 received telephone coaching. The low intensity exercise program consisted of stretching, muscle strengthening with an elastic band, massage, and ball exercise, five days a week, for sixteen weeks. Data were collected from July 2007 to December 2007. $x^2$-test, ANCOVA with SPSS WIN 11.0 program were used to analyse the data. Results: There were statistical differences in the right grasping power in the right hand (p=0.021), Raising behind of right arm (p=0.006), Raising behind of left arm (p=0.007). Conclusion: These results indicate, that a low intensity exercise program with telephone coaching can help improve physical fitness in elders receiving served home visiting nursing care.

• 대한물리의학회지
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• 제12권1호
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• pp.61-66
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• 2017

PURPOSE: The purpose of this study was to investigate the effects of isometric upper limb contraction on the trunk and lower extremity muscles during the sit-to-stand activity in elderly females. METHODS: Eighteen healthy elderly females performed three directional isometric upper extremity contractions (flexion, extension, and horizontal abduction movements) using an elastic band during sit-to-stand activity. Electromyography signals were collected from the internal oblique, erector spinae, rectus femoris, and biceps femoris muscles. RESULTS: Internal oblique activity was greater in bilateral shoulder flexion and bilateral shoulder horizontal abduction than in neutral position (p<.05). Erector spinae and rectus femoris muscle activities in bilateral shoulder flexion was greater than in neutral position and bilateral shoulder extension (p<.05). Biceps femoris activity was significantly greater in bilateral shoulder flexion than in bilateral shoulder extension and horizontal abduction, and in neutral position compared to bilateral shoulder extension (p<.05). CONCLUSION: These results suggest that incorporating isometric upper limb contraction may be beneficial for enhancing the contribution of trunk and lower extremity muscle activities to trunk stabilization during sit-to-stand activity. Therefore, isometric upper limb contraction during sit-to-stand tasks, especially in flexion, may be used to elicit contraction of the lumbopelvic region muscles within a tolerable range, for developing endurance and strength in the elderly.