• Journal of the Society of Naval Architects of Korea
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• v.34 no.4
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• pp.61-71
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• 1997

Numerical and experimental studies are carried out to analyse the resistance characteristics of a hydrofoil catamaran which is advancing on calm water with uniform speed. For the hydrofoil catamaran with modified Wigley hull which has asymmetric transverse section and transom stem, the studies are carried out for the range of Froude number 0.2 to 1.0 and the angle of attack of the hydrofoil $0.0^{\circ}$ to $3.0^{\circ}$. The model tests are carried out in the ship model basin of Inha University. Also the numerical computations using a finite difference method are performed for the simulations of fluid flow around the hull form and the results are compared with the results of the model tests. The present computation results show well quantitative agreement with the experimental results. The experimental results show that the shape and angle of attack of the foils exerts a considerable influence on the running posture and resistance performance of ship.

• Korean Journal of Applied Biomechanics
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• v.31 no.4
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• pp.259-269
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• 2021

Objective: The purpose of this systematic review and meta-analysis was to investigate age-related bimanual coordination functions in older adults. Method: Thirteen studies that compared bimanual coordination functions in older adults with those in healthy young adults qualified for this meta-analysis. We additionally categorized 21 total comparisons from the 13 qualified studies into two types of task-related moderator variables: (1) kinematic versus kinetic movements and (2) symmetry versus asymmetry movements. Results: Random effects model meta-analysis found that older adults revealed significant bimanual coordination impairments as compared with young adults (Hedges's g = -0.771; p < .0001; I² = 74.437%). We additionally confirmed specific bimanual coordination deficits using two moderator variables: 1) kinematic (Hedges's g = -0.884; p < .0001; I² = 0.000%) and kinetic (Hedges's g = -0.666; p = .023; I² = 86.170%). 2) symmetry (Hedges's g = -0.712; p = .001; I² = 74.291%) and asymmetry (Hedges's g = -0.817; p < .0001; I² = 76.322%). The moderator variable analysis indicated older adults indicated bimanual coordination deficits in the upper extremities than healthy young adults while performing kinematic bimanual coordination tasks and asymmetry coordination tasks. Conclusion: These findings suggest that developing motor rehabilitation programs based on asymmetric bimanual movement task for enhancing interlimb coordination functions of older adults may be crucial for increasing their independence in everyday activities. Given that elderly revealed the deficits in lower extremities coordination when older adults perform gait, posture, and balance, future studies should estimate lower limb coordination functions in elderly people.

• Physical Therapy Rehabilitation Science
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• v.10 no.2
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• pp.167-174
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• 2021

Objective: Single leg bridge exercise (SLBE) improves trunk muscle activation and provides muscle stability by aligning joints related to posture. This preliminary study aimed to investigate the effects of SLBE on abdominal muscle activation in subacute stroke patients. Design: Cross-sectional study. Methods: Fifteen subacute stroke patients (9 males, 6 females) voluntarily participated in this study. SLBE was performed on the affected side. Each individual patient performed an SLBE ten times in three sets and was asked to hold their position for 5 s. Muscles activity was recorded using a surface electromyography (EMG) system before and after the SLBE. A surface EMG system was used to analyze the muscle activity during general bridge exercise, including the rectus abdominis (RA), internal oblique (IO), and external oblique (EO) abdominal muscles. Results: Muscle activity of both EO and IO on the affected side significantly increased (p<0.05), whereas the muscle activity of the RA and the three muscles on the unaffected side did not show a significant difference. In addition, improvement in muscle asymmetry of the EO and IO showed a significant change after SLBE (p<0.05). Conclusions: SLBE is effective in activating the abdominal muscles of stroke patients on the affected side and is a helpful exercise intervention that activates the muscles to transform asymmetric abdominal muscles into symmetric patterns.

• The Journal of the Korea Contents Association
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• v.22 no.3
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• pp.576-585
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• 2022

In determining the cause of dysmenorrhea, it is necessary to investigate postural alignment and balance. The purpose of this study is to compare and analyze whether there is a difference in posture alignment and foot pressure balance according to the dysmenorrhea degree. The subjects were twenty female students in their 20s, who had pain caused by dysmenorrhea. According to the degree of dysmenorrhea, the subjects were divided into mild and severe groups. In the results, there was a significant difference only in shoulder height asymmetry angle between the mild and severe groups (p<0.05), and there was no significant difference in pelvic and knee joint alignment. In the correlation analysis, there was a significant positive correlation between the dysmenorrhea score (MDQ) and shoulder height asymmetry angle was found. These results indicate that dysmenorrhea symptom and asymmetric alignment of shoulder are related. To analyze these factors, further research will need to investigate the correlation between dysmenorrhea and spinal alignment.

• Journal of International Academy of Physical Therapy Research
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• v.4 no.2
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• pp.573-587
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• 2013

The purpose of this study was conducted in order to analyze the effects of the manual intervention and self-corrective exercise models of general coordinative manipulation(GCM) on the balance restoration of spine & extremities joints with distortions and mal-alignment areas. The subjects were the members who visited GCM Musculoskeletal Prevent Exercise Center from March 1 2012 to December 31 2013 because of spine & extremities joints distortion and mal-alignments, poor posture, and body type correction. All subjects were diagnosed with the four types of the GBT diagnosis. And according to the standards of the mobility vs stability types of the upper & lower body, they were classified into Group 1(40 persons) and Group 2(24 persons). For every other day for three times a week, GCM intervention models were applied to all subjects for four weeks, adding up to 12 times in total. Then the balance restoration effects were re-evaluated with the same methods. The results are as follows. 1) Balance restoration effects of VASdp(Visual analysis scale pain & discomfort) and ER(Equilibrium reaction: ER) came out higher in GCM body type(GBT) II III IV of Group 1. 2) In case of balance restoration effects in Moire and postural evaluation areas, Group 1 was higher and cervical and scapular girdle were higher in Group 2. The balance restoration of the four GBT types was significant in all regions(p<.05), and the scapular girdle came out as high in the order of GBTII IV I. 3) In case of thoracic-lumbar scoliosis and head rotation facial asymmetric cervical scoliosis ribcage forward, the balance restoration effects of the upper body postural evaluation areas came out the highest in Group 1 and Group 2, respectively. The balance restoration effects of the four GBT types were significant in all regions(p<.05), and came out the highest in lumbar scoliosis GBTIII I, ribcage forward and thoracic scoliosis GBTII IV. 4) The balance restoration effects of the lower body postural evaluation areas came out higher in Group 1 and Group 2 for pelvis girdle deviation patella high umbilicus tilt and hallux valgus foot longitudinal arch: FLA patella direction, respectively. The balance restoration effects of the four GBT types were significant in all regions(p<.05), and came out the highest in pelvis girdle deviation GBTIII I and patella high-direction GBTIV II I. 5) The balance restoration effects between the same GBT came out significant (p<.05) in all evaluation areas and items. The conclusions of this study was the manual intervention and self-corrective exercise models of the GCM about the mal-alignment of the spine & extremities joints across the whole body indicated high balance restoration effects(p<.05) in spine & extremities joints in all evaluation areas.

• Strategy21
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• s.34
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• pp.58-92
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• 2014

Even after S. Korea took 5.24 Measure(24 May 2014), N. Korea has not stopped raising provocations such as the shelling of Yeonpyeong Island, electronic and cyber attacks. To make matters worse, the communist country lunched long-range missiles(twice) and conducted 3rd nuclear test, escalating tensions which could possibly lead to an all-out war. Korean Government failed to respond properly. However, escalation into an all-out war was deterred by the CFC immediately carrying out its peacetime duty(CODA). The US made a rapid dispatch of its augmentation forces(Aircraft carrier, nuclear-powered submarine, strategic bomber, F-22) to the Korean Peninsula. In recognition of the importance of the Combined Forces Command, since May 2013 the Park Geun-Hye Administration has been pushing ahead with re-postponement of Wartime Operational Control Transfer(which initially meant the disassembling of the CFC as of 1 December 2015) More recently, there has been a series of unusual indicators from the North. Judging from its inventory of 20 nuclear weapons, 1,000 ballistic missiles and biochemical weapons, it is safe to say that N. Korea has gained at least war deterrence against S. Korea. Normally a nation with nuclear weapons shrink its size of conventional forces, but the North is pursuing the opposite, rather increasing them. In addition, there was a change of war plan by N. Korea in 2010, changing 'Conquering the Korean Peninsula' to 'Negotiation after the seizure of the Greater Seoul Metropolitan Area(GSMA)' and establishing detailed plans for wartime projects. The change reflects the chain reaction in which requests from pro-north groups within the South will lead to the proclamation of war. Kim, Jeong-Un, leader of N. Korean regime, sent threatening messages using words such as 'exercising a nuclear preemptive strike right' and 'burning of Seoul'. Nam, Jae-June, Director of National Intelligence Service, stated that Kim, Jung-Un is throwing big talks, saying communization of the entire Korean Peninsula will come within the time frame of 3 years. Kim, Gwan-Jin, Defense Minister, shared an alarming message that there is a high possibility that the North will raise local provocations or a full-fledged war whenever while putting much emphasis on defense posture. As for the response concept of the Korean Government, it has been decided that 'ROK·US Combined Local Provocation Counter-Measure' will be adopted to act against local provocations from the North. Major provocation types include ▲ violation of the Northern Limit Line(NLL) with mobilization of military ships ▲ artillery provocations on Northwestern Islands ▲ low altitude airborne intrusion ▲ rear infiltration of SOF ▲ local conflicts within the Military Demarcation Line(MDL) ▲ attacking friendly ships by submarines. Counter-measures currently established by the US involves the support from USFK and USFJ. In order to keep the sworn promise, the US is reinforcing both USFK and USFJ. An all-out war situation will be met by 'CFC OPLAN5027' and 'Tailored Expansion Deterrence Forces' with the CFC playing a central role. The US augmentation forces stands at 690,000 troops, some 160 ships, 2,000 aircraft and this comprise 50% of US total forces, which is estimated to be ninefold of Korean forces. The CFC needs to be in center in handling both local provocations and an all-out war situation. However, the combat power of S. Korean conventional forces is approximately around 80% of that of N. Korea, which has been confirmed from comments made by Kim, Gwan-Jin, Defense Minister, during an interpellation session at the National Assembly. This means that S. Korean forces are not much growing. In particular, asymmetric capabilities of the North is posing a serious threat to the South including WMD, cyber warfare forces, SOF, forces targeting 5 Northwestern Islands, sub-surface and amphibious assault forces. The presence of such threats urgently requires immediate complementary efforts. For complementary efforts, the Korean Government should consider ① reinforcement of Korean forces; putting a stoppage to shrinking military, acquisition of adequate defense budget, building a missile defense and military leadership structure validity review, ② implementation of military tasks against the North; disciplinary measures on the sinking of ROKS Cheon-an/shelling of Yeonpyeong Islands, arrangement of inter-Korean military agreements, drawing lessons from studies on the correlation between aid for N. Korea, execution of inter-Korean Summit and provocations from the North, and ③ bolstering the ROK·US alliance; disregarding wartime operational control transfer plan(disassembling of CFC) and creation of a combined division.