• 대한인간공학회지
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• 제27권3호
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• pp.71-79
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• 2008

Walking shoes for walking and jogging have been used to enjoy lots of leisure time. Functional shoes such as walking shoes have special functions to improve body motility by changing of shoe shapes. The walking shoes could improve the motility by structural transformation of outsole as increase degrees of heel and toe. The study on insoles has not been conducted enough on the contrary of the study of outsole. The purpose of this study is to perform ergonomics analysis whether the Arch Supported insoles have an improving effect of muscle activities or not. Experiments were performed with 6 subjects who are health and haven't experienced any diseases past. EMG(Electromyography) and Foot Pressures were measured repeatedly for 5 seconds at 0 hour, after 1 hour and after 2 hours of walking. Insoles used for experiment are normal insole, insole inserted Arch Support and pad. The electrodes for EMG measurement were set on waist (erector spinae), and thigh (vastus lateralis), calf (gastrocnemius). Evaluations of EMG were analyzed by shift of MF (Median Frequency) and MPF (Mean Power Frequency). Foot Pressure was analyzed by mean pressure of feet and change of walking time. As results, Arch Support insole had larger frequency shift value than that of normal insole. Frequency shift between Arch Support insoles and normal insole showed significant difference on 95% confidence interval. And insole 1 has the highest value of frequency shift. For results of foot pressure, Arch Support insoles show continuous decreasing tendency when comparing with normal insoles by changing of times. Also, insole 1 has the highest decreasing value of foot pressure. Therefore, this study presented that the Arch Support insole can promote muscle activities and improves comfort for a prolonged walking.

• Journal of Acupuncture Research
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• 제17권2호
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• pp.85-93
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• 2000

We came to the conclusion after considering all the information from many kinds of books on the circulation courses, cross-link points, functions and the symptoms of disease of Chongmai. The results were as follows : 1. The Chongmai that starts from a Uterus flows to Dazhu through the inside of vertebra after joining Renmai and Duimai at Huiyin. The Chongmais up-line that comes out from Qichong into a surface of body arrives and is scattered at a chest through an abdomen. One strand of them goes upward again and is connected to a throat and lips area. After coming out from Qichong, separated down-line is divided into two parts when it arrives a inner part of a heel through the inner part of a leg. One is for an instep, the other is for the sole of a foot. 2. We call it "Sea of Twelve Meridians" or "Meridian's Sea". Because Chongmai controls all of Meridian by acquired "Basic energy" as getting Stomach's energy, Kidney's energy and air-energy, and there are responsible of physiological phenomenon control. And also we name it "Sea of Blood", because it starts from and provides a nutrition to Uterus. 3. All of these four Meridian such as Renmai, Kidney Meridian, Stomach Meridian and Spleen Meridian are ones that flow around the part of a chest and an abdomen. Chongmai makes energy and blood circulation of a chest and an abdomen be stronger and be controlled. Therefore it makes viscera, bowels and body surface be warm and given a nutrition. So Chongmai becomes "Sea of Viscera and Bowels". 4. Chongmai provides a nutrition for ligament and muscle and makes legs get warm as making energy and blood circulate from head to foot. If Chongmai is energetic, hair is completely easy to grow. 5. To see in pathological phase, Chongmais failure or weakness causes like a chest pain, stomachache, heart attack, a menstrual irregularity and sterility and so on. And also if Chongmai is damaged, it happens that giving a nutrition for lips area is stopped, and then mustache doesn't grow any more.

• 대한조선학회논문집
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• 제56권6호
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• pp.550-558
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• 2019

The roll motion of a general vessel, which is more influenced by resonance as compared to other motions, adversely affects the passenger and hull. Therefore, reducing the roll motion through an anti-rolling system is critical, and most ships use various devices such as anti-rolling tanks, bilge keels, and fin stabilizers to accomplish this. In this study, a simplified model is developed for the application of an anti-rolling device for unmanned semi-submersible vessels. The applied anti-rolling device is installed on the stern and stem of a ship using a pair of servo motors with added weight, and the motor is controlled through the Arduino. The moment of the motor is designed and implemented based on a mathematical model such that it is calculated through the restoring force according to the heel angle of the ship. The performance of the proposed system was verified by utilizing the roll damping coefficient calculated by the free-roll decay test and logarithmic decrement method and was validated by a towing tank test. The system is expected to be used for unmanned vessels to perform sustainable missions.

• Physical Therapy Rehabilitation Science
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• 제7권1호
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• pp.35-40
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• 2018

Objective: The purpose of this study was to investigate the immediate effect of applying self-myofascial release (SMR) to the plantar fascia using a foam roller on hamstring and lumbar spine superficial back line (SBL). Design: Randomized controlled trial. Methods: Thirty-one healthy adults agreed to the method and purpose of the study. Selection and exclusion criteria were screened, and baseline measurements for the Toe Touch test and passive straight leg raise (PSLR) test were obtained. The participants were then randomly assigned to the SMR group or the sham group. After group assignment, the SMR group rolled the surface of the foot from the heel to the metatarsal head using a foam roller for 5 minutes. The sham group received passive mobilization of the ankle joint in the supine position. Afterwards, the Toe Touch test and the passive straight leg-raise test were re-assessed. Results: In the SMR group, the Toe Touch test results showed significant improvement (p<0.05). Left and right PSLR test results showed a significant increase (p<0.05). In the sham group, there was no significant difference between pre and post-test results. The SMR group showed a significant difference in the PSLR test and Toe Touch test compared to the sham group (p<0.05). Conclusions: The results of this study showed that SMR on the plantar fascia was immediately effective for improving the flexibility of the SBL of the lumbar spine and hamstring.

• 대한족부족관절학회지
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• 제5권1호
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• pp.69-73
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• 2001

Purpose: The purpose of this study is to report the result of endoscopic assisted curettage and bone graft for the treatment of simple bone cyst in the calcaneus. Materials and Methods: Three cases in three patients who had curettage and bone graft of simple bone cyst in the calcaneus under endoscopic view were prospectively reviewed. A minimum follow-up of 1 year was required for entrance into the study. The results of treatment were clinically and radiologically assessed. Results: One case with preoperative heel pain gained complete relief of the pain at postoperative four weeks. All three cases had radiological union of grafted bone at an average of thirteen weeks after the operation. Shortened hospitalization and decreased postoperative pain were remarkable. Complications such as infection, skin necrosis, nerve injury, and, fracture were not seen. There was no evidence of the recurrence of the cyst in all three cases. Conclusion: Endoscopic assisted curettage and bone graft of simple bone cyst in the calcaneus is thought as an effective alternative procedure avoiding the possible complications of the classic method.

• 한국항해항만학회지
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• 제30권5호
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• pp.375-379
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• 2006

세일링요트의 추진시 횡류를 방지하기 위하여 선체 하부에 킬을 부착하게 되는데 이는 세일의 양력에 의한 횡흐름을 멈추게 하는 역할과 힐 모멘트를 없애고 복원력을 생기게 한다. 이는 안전성에 영향을 미치기 때문에 적절한 킬의 선택은 중요하다고 할 수 있다. 또한 킬 하부에 부가물의 부착은 발라스트 중량중심을 낮춤으로서 선체 복원력에 중요한 영향을 미치므로 킬에 대한 최적형상 도출은 매우 중요하다. 이에, 본 연구에서는 저항성능 향상을 위한 동일 침수표면적의 핀킬 하부 부가물에 따른 저항특성을 비교 실험하였다. 실험방법으로는 회류 수조를 이용하여 3가지 핀킬 하부 부가물 모형킬을 모형선에 부착하여 형상별 저항특성을 비교 분석하였다. 분석 결과에 따른 저항감소 최적 형상을 도출 하였다.

• 한국구조물진단유지관리공학회 논문집
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• 제21권3호
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• pp.86-92
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• 2017

장스팬 구조물은 사용하중 하에서 바닥진동 문제가 발생할 가능성이 크다. 따라서 구조물 바닥판의 진동성능을 향상시키기 위한 가장 일반적인 방법은 슬래브의 두께를 증가시키는 것이지만 기존의 구조시스템에서 슬래브의 두께를 증가시키면 슬래브 자중의 증가로 건축물 전체의 효율성이 떨어지게 되는 문제점이 있다. 따라서 슬래브의 두께를 증가시키면서도 자중은 크게 증가하지 않는 바닥판 시스템으로 중공슬래브에 관한 관심이 커지고 있는 상황이다. 이에 부력방지능력 및 시공성 향상을 위하여 데크플레이트와 경량성형재를 결합한 형태의 중공슬래브를 개발하였고, 이 중공슬래브를 적용한 실물(mock-up) 건축물에 대한 사용성 검증을 위한 진동성능 평가를 수행하였다. 측정된 결과값을 분석한 결과, 일본건축학회의 "건축물의 진동에 관한 거주 성능 평가지침"에 의하면 1등급인 거실, 침실에 사용해도 될 수준으로 평가되었다.

• 한국운동역학회지
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• 제20권4호
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• pp.381-386
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• 2010

This study examined the changes in the walking pattern during level walking under low illumination conditions. Fourteen male subjects ($22.1{\pm}2.21$ years, $174{\pm}3.74\;cm$, $68.86{\pm}10.81\;kg$) with normal vision and no disabilities were enrolled in this study. All experiments were performed on a level walkway with three conditions: normal walking (preferred & low speed) and walking with low illumination. 3D motion capturing system was used for acquisition and analysis of the walking motion data with a sampling frequency of 120Hz. The walking speed, normalized jerk(NJ) at the center of mass(COM), wrist and heel, knee and elbow joint angle, ratio of the knee joint angle to elbow joint angle and the toe clearance on stance phase were used to compare the differences in walking pattern between the two illumination conditions, The results showed that the walking speed and joint angles decreased in low illumination, whereas the NJ and toe minimum clearance increased. In low illumination, most variables were similar to effects of low speed walking, but toe clearance was different from the effects of low speed. These results can be used as primary data for examining the changes in the level walking pattern of young adults under low illumination. Further study will be needed to compare these results in young adults with those in the elderly.

• 한국운동역학회지
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• 제28권1호
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• pp.29-35
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• 2018

Objective: The purpose of this study was to determine the asymmetry of vertical ground reaction force (GRF) components between dominant and non-dominant legs in rested and fatigued states in prolonged running. Method: Twenty healthy men, heel strikers, were included (age: $24.00{\pm}5.0years$; height: $176.1{\pm}6.0cm$; body mass: $69.0{\pm}6.0kg$) in this study. Subjects ran on an instrumented treadmill for 130 minutes. During treadmill running, GRF data (1,000 Hz) were collected for 20 strides at five minutes (rested) and 125 minutes (fatigued) running while they were unaware of collecting data. Asymmetry indexes (ASI) were calculated to quantify the asymmetry magnitude in rested and fatigued states. Paired t-test was used to verify the differences between dominant and non-dominant legs in rested and fatigued states. In addition, one-way repeated measure analysis of variance was applied for comparison of ASI of both states. The level of significance was set at p < .05. Results: Passive force peak magnitude, loading rate, and impulse affecting the development of running injury were found significantly greater in dominant leg than in non-dominant leg at rested state (p < .05). However, passive force peak time and active force peak magnitude were found significantly different between legs in fatigued state (p < .05). To determine changes in percentage of asymmetry between legs in both states, ASI was used. ASI for all variables increased in fatigued state; however, no significant differences were found between both states. Conclusion: This study found that fatigue did not affect differences in vertical GRF between dominant and non-dominant legs and asymmetry changes.

• 한국운동역학회지
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• 제17권3호
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• pp.147-154
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• 2007

This study's purpose is to investigate the effects on leg muscle activity caused by perturbation, using a trapdoor system during the support phase of gait for healthy adults (n = 6, height $177.5{\pm}5.5cm$, weight $81.0{\pm}9.5kg$, age $30.0{\pm}3.3yrs$). The trapdoor had the functional ability of causing inversion or eversion. The release time for the trapdoor was specified for two times, 0.3 and 0.5 seconds after heel contact. While altering these variables, EMG was recorded for the leg muscles (rectus femoris, biceps femoris, vastus lateralis, tibialis anterior, gastrocnemius, soleus). The following conclusions were derived. The steptime was longer for the 0.5s eversion than 0.3s inversion condition. So in order to regain stability after the perturbation the unsupporting leg reached forward rapidly. This quick reflex can be observed through the center of pressure (COP) and its rapid change in direction. The gastrocnemius was activated throughout the total experiment. There was a low amount of activity recorded in the rectus femoris, vastus lateralis and tibialis anterior except for the condition of inversion 0.3s. For most of the conditions, the highest average EMG peak values were recorded during the condition of inversion 0.3s. The iEMG patterns were similar for the conditions of inversion 0.3s and eversion 0.3s. To cope with the rapid change in these conditions, the biceps femoris was activated. During the experiment except for the condition of normal gait, the activity of the soleus and gastrocnemius was relatively high. Therefore, to prevent injury from perturbation of the lower leg strengthening of the soleus and gastrocnemius is required. Likewise to prevent injury to the thigh strengthening for the biceps femoris.