• Korean Journal of Applied Biomechanics
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• v.33 no.1
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• pp.17-24
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• 2023

Objective: The purpose of this study was to investigate the effects of different frequency on of knee extensors muscle function during electrical muscle stimulation (EMS). Method: In this research, 40 subjects who have no musculoskeletal disorder, and less than a year workout experience were recruited in order to analyze effects of EMS with different stimulus frequency. Forty subjects were randomly divided into four groups of ten subjects in each group. A EMS training program with different frequencies (without EMS [WE], EMS with frequency 30 Hz [E30], EMS with frequency 60 Hz [E60], EMS with frequency 90 Hz [E90]) was assigned to each group. Throughout eight weeks of training, test subjects were simultaneously carried out knee extension exercises such as squat, leg extension, and leg-press while using EMS with different frequency (20 min, pulse width 250 ㎲, on-off ratio 1:1). Isokinetic knee extension strength, muscle activity of the rectus femoris (RF), the vastus medialis (VM), and the vastus lateralis (VL), and the median frequency of the RF, the VM, and the VL were collected and compared between pre and post training in order to find effects of applying EMS with different frequencies. For each dependent variable, a one-way ANOVA was to determine whether there were significant differences among four different conditions (p<.05). When a significant difference was found, post hoc analyses were performed using the contrast procedure. Results: When compared to WE and E90, E30 causes significant increase in isokinetic knee extension strength. No significant differences were found in EMG values across different EMS conditions. However, the median frequency of the VM in E30 was significantly increased than the corresponding value for WE. Conclusion: The results of this study showed that EMS training with 30 Hz frequency had positive effect on knee extensor. Based of the findings of the present study, EMS training with lower frequency may help the performer to focus on developing strength in knee extensor muscles.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2003.10a
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• pp.87-92
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• 2003

Generally, in jack up rig design for harsh environment, its leg height is a major factor for achieving a sufficient serviceability & operability in terms of the worst environment and the workable depth. Due to difficulties in constructing such a high-slender leg, inaccessibility of yard fabrication equipment, etc. the construction of Jack up rig fur harsh deep sea has not been common. Method using heavy crawler crane, fabrication tower or extension by the floating crane vessel is still conventional construction but, considering high cost fur mobilizing heavy lift vessel (HLV) or additional marine work for implementing preload / full height test at sea, the ground-base construction is much advantageous. Air skidding method (ASM hereafter) is ground-based construction methodology, newly developed due to such requests. ASM could also be extended to similar engineering fields. This paper presents the operating sequence, design parameters and procedure which were verified through successful operation at the end of May 2002.

• Journal of International Academy of Physical Therapy Research
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• v.11 no.2
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• pp.2036-2041
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• 2020

Background: Ankle sprain in the Lead Leg Side (ALLS) is common in fencing athletes, and studies comparing the ankle range of motion (ROM) and strength of both legs are insufficient. Objectvies: To compare the ankle ROM and hip strength between two legs in fencing athletes who has ankle instability in the lead leg side. Design: Cross-sectional design. Methods: Seven fencing athletes with ankle instability participated in this study, and they randomly assigned into ankle in the Lead Leg Side (ALLS) and ankle in the Rear Leg Side (ARLS). Instability was determined by the Cumberland Ankle Instability Tool (CAIT), and then joint ROM and hip muscle strength were measured. Results: There were significant differences in dorsiflexion ROM, hip strength (extension and abduction) between the ALLS with ankle instability and ARLS (P<.05). Conclusion: This study suggests that the ankle ROM and hip muscle strength of ARLS are greater than ALLS in fencing athletes with ankle instability.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2011.06a
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• pp.1423-1424
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• 2011

• The Journal of Korean Physical Therapy
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• v.11 no.2
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• pp.149-161
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• 1999

The purpose of study wan to compare the effect of balance performance in the elderly by the strengthening exercise. Thirty-one health elderly women aged 60 to 79 years participated in this study. Participants were divided into exercise(21) and control group(10). Exercise participants received strengthening exercise for 45 minutes in three times a week for 6 weeks while control subjects continued their normal activities, Exercise included resisted hip flexion, extension, abduction and adduction, knee flexion and extension, ankle dorsiflexion and plantrarflexion. All subjects were assessmented clinical test of sensory interaction and balance. one leg stance test, Berg balance test. Exercise and control subjects were teated before, midway through, and at the end of the trial. These collected data were analyzed by using oneway and repeated ANOVA, scheffe's test, 1-test and correlation. The results of this study were as fellows. 1. There were statistically significant difference in balance performance clinical teat of sensory interaction, and balance(p<.01), one leg stance test(p<.05), Berg balance test(p<.05) by the strengthening exercise. 2. There was correlation between static balance and dynamic balance(p<.01). 3. There was correlation between static balance and weight(p<.05), dynamic balance and height(p<.01), and weight(p<.01).

• Journal of Agricultural Extension & Community Development
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• v.23 no.1
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• pp.27-37
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• 2016

This paper estimated the demand function of the cuts of pork by using the consumer panel and the weather data from the Korea Meteorological Administration with a log-log model and AIDS model. The results show that the price elasticity of demand for cuts of pork is high in the sequence of arm shoulder, leg, special cuts, tenderloin, blade shoulder. In contrast, spare rib, belly and loin are classified as low price elasticity of demand. The income elasticities of demand for leg and blade shoulder are 11% and 7.6% respectively. The loin is classified as inferior goods, because demand decreases when income increases. The results also demonstrate show that the demand increases highly in the sequence of loin, arm shoulder, spare rib, belly if housewife is older, and the demand of belly increases when family number increases. Belly substitutes every cut except spare rib, and tenderloin substitutes special cuts. Spare rib, on the other hand, does not substitute other cuts. In addition, job status, family member, husband job, purchasing place, consumer characteristic, eating-out times, purchasing time, and weather are statistically significant.

• The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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• v.25 no.1
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• pp.21-27
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• 2019

Background: The purpose of this study was to investigate the effects of Graston technique for lower extremity range of motion (ROM), muscle strength, walking ability in hemiplegia patients. Methods: Twelve subjects participated in this study. The ROM of the knee extension was measured by 90-90 straight leg raise test, the hamstring and quadriceps muscle strength was collected by utilizing a handheld dynamometer. In addition walking speed was evaluated by 10 meter walking test. The group was applied intervention using a Graston instrument for one minute. After intervention, immediate effect was assessed. The significant level was set at ${\alpha}=.05$. Results: The ROM of the knee extension, quadriceps muscle strength and walking speed were significantly increased. Hamstring muscle strength was significantly reduced. Conclusion: The results of this study suggest that Graston instrument technique has the effect of instantaneously flexibility the muscles, and the muscle applied with the technique has weakened, while the muscle of the opposite side has increased the muscle strength. In addition, the muscle flexibility and the walking speed have increased.

• Archives of Plastic Surgery
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• v.32 no.4
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• pp.447-453
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• 2005

The coverage of soft tissue defects around the knee joint or upper one third of lower leg presents a difficult challenge to the reconstructive surgeon. Various reconstructive choices are available depending on the location, size and depth of the defect. The authors present their clinical application of a medial sural artery perforator island flap as a useful alternative method for upper one third of lower leg and knee reconstruction. From 2002 to 2004, we operated total 4 patients (total 4 flaps) using the medial sural artey perforator island flap for coverage of the defect on upper one third of lower leg and knee, of 4 patients, 3 patients was men and one was woman. Average patient age was 54.6 years. The largest flap obtained was 10x8cm2. Postoperative follow up of the patients ranged from two to 33 months. In two cases, defects was located on upper one third of lower leg and in other two cases, defects were on the knee. All four cases had bone exposure open wound. In angiography, 2 cases had injured in the anterior tibial artery, 1 case had injured in the posterior tibial artery. There were no diabetes or other vascular disease. All 4 flaps were survived completely, without minor complications such as venous congestion and hematoma. Donor morbidity was restricted substantially to the donor linear scar. There were no functional impairment. As the main advantages of the medial sural perforator island flap, it ensures constant location and reliable blood supply without sacrificing any main source artery or damaging underlying muscle. This procedure is valuable extension of local flap for defect coverage with minimal functional deficit donor site and good aesthetic result on the defect. We consider it as one of the useful methods of the upper one third of lower leg and knee reconstruction.

• The Journal of Dong Guk Oriental Medicine
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• v.5
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• pp.79-95
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• 1996

When we see normal gait, gait cycle is seperated as stance phase and swing phase. It needs 6 determinant of gait of pelvic rotation, pelvic tilt, knee joint of stance phase, ankle and foot motion, ankle and knee motion, and pelvic movement to be accomplished. In addition, a joint and muscle action is accomplished biomechanically at the same time with its gait cycle. In oriental medicine, the relationships between chang-fu physiology and meridian physiology are summaried as follows ; ${\bullet}$ chang-fu physiology : Spleen manages the extremities. Liver manages soft tissues. Liver stores blood. Kidney stores essences. Kidney manages bones. ${\bullet}$ meridian physiology : The Leg Greater Yang Meridian and meridian soft tissues The Leg Yang-Myeong Meridian and meridian soft tissues The Leg Lesser Yang Meridian and meridian soft tissues The Leg Greater Yin Meridian and meridian soft tissues The Leg Lesser Yin Meridian and meridian soft tissues The Leg Absolute Yin Meridian and meridian soft tissues Especially, we can find out relations between in a "blood supplied feet can walk well" that explains "blood regulations and by liver nourishing effects"that is the closest concept of muscle. Abnormal gaits are due to three causes as following; first, physical defect secoud, pain third, nervous system or instability of muscle. In oriental medicine, we can know relationship in "atrophy, numbness, stroke, convulsion, muscular dystrophy of knee, rheumatoid arthritis, five causes of infantile growing defects, five causes of softening, sprain". Especially, atrophy is the most important symptom. Gait evaluation should be emphasized where a point can walk 8 feet to 10 feet considering stride width, stride length, the body weight center, stride number, flexion, extension, rotation of a joint as a standard factor. The point is we should find out something strange in a patient's side, front and back view. After that we should find out its cause as an index that we can observe abnormal findings in a joint and muscle.

• Journal of the Korean Society of Physical Medicine
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• v.2 no.2
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• pp.101-112
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• 2007

Purpose : The purpose of this study was to evaluate influence of sacroiliac joint mobilization on lower extremity muscle strength. Methods : The subjects were consisted of thirty patients who had Leg length inequality(LLI) of more than 10mm(16 females. 14 males) from 21 to 41 years of age(mean aged 24.87). All subjects randomly assigned to sacroiliac joint mobilization group(n=15), control group(n=15). sacroiliac joint mobilization group received sacroiliac joint mobilization about 10 minutes for 3 times per week during 4 weeks period. Control group not received intervention during 4 weeks period. The tape measure method(TMM) was used to measure functional Leg length inequality. Biodex System 3 Pro was used to measure strength of Knee extension & flexion. All measurements of each subjects were measured at pre-test, 2weeks post-test and 4weeks post-test. Results : 1. The LLI of sacroiliac joint mobilization group was significantly reduced according to within treatment period(p<.05), most significantly reduced between pre-test and post-test(p<.05). sacroiliac joint mobilization group significantly more reduced than control group(p<.05). 2. The knee extension strength of sacroiliac joint mobilization group was significantly increased according to within treatment period(p<.05), most significantly increased between pre-test and post-test(p<.05). sacroiliac joint mobilization group significantly more increased than control group(p<.05). 3. The knee flexion strength of sacroiliac joint mobilization group was significantly increased according to within treatment period(p<.05), most significantly increased between pre-test and post-test(p<.05). sacroiliac joint mobilization group significantly more increased than control group(p<.05). Conclusion : sacroiliac joint mobilization can reduce LLI and increased lower extremity muscle strength.