• The Journal of the Acoustical Society of Korea
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• v.12 no.3
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• pp.34-42
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• 1993

수중운동 추적체계의 추적 성능은 표적에 부착된 핑거로부터의송신음향이 수중센서에 도달하기 까지의 시지연과, 해저에 부설된 각 센서가 시지연을 이용하여 기하학적으로 계산하는 LOP를 얼마나 정확하게 추출하느냐에 달려있다. 본 논문에ㅓ는 수중운동 추출하느냐에 달려있다. 본 논문에서는 수중운동 추적체계의 추적성능을 예측하기 위하여 먼저 CRLB를 이용한 시지연 예측오차의 기준경계식을 유도하고, 임의 표적운도에 이를 적용시켜 추적거리오차를 추출하였다. 시뮬레이션 결과, 표적이 원형 기동하는 경우보다 직선 기동하는 경우에 표적위치에 따라 오차의변화가 더 심하고, 수중운동 추적체계의 이론적 설계성능은 주파수 대역에 의해 영향을 가장 많이 받음을 확인하였다. 한편 4km*4km 범위의 수중센서 패턴을 사용하고 주파수 대역폭을 200Hz로 취한 경우 시간지연에 의한 수중운동 추적체계의 이론적 추적오차는 0.24m 이내로 시뮬레이션 되었다.

• 대한근관절건강학회:학술대회논문집
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• 1998.11a
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• pp.296-302
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• 1998

• The Journal of the Korea Contents Association
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• v.9 no.10
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• pp.218-226
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• 2009

This study conducted the following experiment to examine effects of bone metabolism on aquatic exercise, Drynariae Rhizoma and aquatic exercise with Drynariae Rhizoma. This experiment was conducted to compare bone strength, bone mineral density, weight, change of femur, osteocalcin, ALP, Ca and P effects by aquatic exercise for 6 weeks, Drynariae Rhizoma and Drynariae Rhizoma for aquatic exercise with 40 SD rats of postoophorectomy osteoporosis and it divided 10 subjects. experiment group (I) is applying postoophorectomy osteoporosis group, (II) is applying aquatic exercise group, (III) is applying Drynariae Rhizoma group and (IV) is applying aquatic exercise with Drynariae Rhizoma group. These result lead us to the conclusion that osteocalcin were showed a statically increase and blood Ca level were showed a statically decrease on other groups compare to group(I). Consequently, aquatic exercise and Drynariae Rhizoma would be lead to increment of bone metabolism on postoophorectomy osteoporosis.

• The Journal of the Korea Contents Association
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• v.9 no.12
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• pp.656-664
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• 2009

The purposes of this study were to examine whether aquatic exercise has influence on the neuroplasticity and vestibulo-motor function in diffuse brain injury rats. 80 Sprague-Dawley rats were assigned to four groups; Group I: control group (n=20), Group II: aquatic exercise (n=20), Group III: treadmill exercise with change of velocity and inclination (n=20), Group IV: simple treadmill exercise (n=20). And we applied exercise each groups for 3 weeks except Group I. Before the rats were sacrificed to identify immunohistochemistry study at each time of measurement day, Rota-Rod test was given to assess changes in vestibulomotor function. then, the immunohistochemistry study of GAP-43 in discrete regions of the rat brain was performed to measure changes in neuroplasticity. The results demonstrate that aquatic exercise group is more effective than other groups. expression of GAP-43 and vestibulo-motor function were increased most in aquatic exercise group. Therefore, this study suggest that aquatic exercise may effective therapeutic approach to increase neuroplasticity and vestibulo-motor function in traumatic brain injury.

• Korean Journal of Applied Biomechanics
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• v.19 no.3
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• pp.539-547
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• 2009

The purpose of this study was to investigate the changes of kinetic and kinematic parameters in obstacle gaits after 12 weeks of an aquatic exercise program. Eight female elders walked in four different heights of obstacles(0, 2.5, 5.1, & 15.2cm) on their self-selected speed. The ROM of hip was significantly increased after the aquatic exercise program. Swing and Stance duration were decreased. The step length was significantly increased and the step width was decreased. After the exercise program the clearance between the right foot and the top of obstacle(except 15.2cm) increased and the crossing speed was increased. The braking force, propulsive force, braking impulse, and propulsive impulse were significantly changed after the aquatic exercise program. The 12 weeks of the aquatic exercise program resulted in lower body strength and balance gains in female elders. The improvements were associated with changes in kinetic and kinematic parameters leading to an obstacle-crossing speed and a safer lower-limb control. The aquatic exercise program is suggested as an effective intervention to promote gait ability and prevent fall-related to the injuries.

• The Journal of the Korea Contents Association
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• v.10 no.4
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• pp.206-215
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• 2010

This study was designed to investigate the effects of mild hypothermia and Aquatic exercise on function Activity after experimental Spinal Cord Injury(SCI) rats. Experimental groups were divided into the control group (non-treatment after SCI induction), group I(hypothermia after SCI induction), group II(exercise after SCI induction), group III(hypothermia and exercise after SCI induction). After operation, rats were examined neurological motor behavior test at 3, 7, 14, 21 days and Immunohistochemical assessment at 3, 7, 21 days.Each other 14 days were a statistically significant difference between control group and group II, III(p<.001) in BBB scale, between control group and group III(p<.05) in grid walk test. In mmunohistochemical assessment, there was appeared highest express in group III. Based on these results, mild hypothermia and exercise was effected functional Activity after SCI.

• The Journal of the Acoustical Society of Korea
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• v.40 no.4
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• pp.314-319
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• 2021

The measurement of the Underwater Radiated Noise (URN) for the underwater vehicle should consider both the acoustic interference due to the surface reflection and the calculation of the Closet Point of Approach (CPA). In this paper, I tried to analyze the underwater vehicle's URN using the Lloyd's mirror effect. First, the theoretical Lloyd's mirror pattern was compared with the sea trial result, and the sea trial results corresponded well with the theoretical predicted pattern. And then the CPA distance could be estimated by the Lloyd's mirror pattern. As a results, acoustic source level shows the spectral fluctuation due to the acoustic interference of the Lloyd's mirror effect.

• 대한근관절건강학회:학술대회논문집
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• 2001.04a
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• pp.191-196
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• 2001

• Journal of the Korea Society of Computer and Information
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• v.26 no.8
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• pp.75-81
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• 2021

The purpose of this study was to investigate the effects of aqua exercise program on body composition, blood components, and physical fitness in the elderly women. This study included 23 elderly women. The aqua exercise program was performed for fifty minutes a day, 2 times a week for 12 weeks with moderate-intensity level. Data was analyzed with SPSS using descriptive statistics and the paired t-test. The findings of this study presented that the aqua exercise program showed significant improvements in the body mass index (t=2.42, p=.024), the abdominal circumference (t=4.36, p<.001), and the level of blood glucose (t=3.19, p=.004) and LDL cholesterol (t=3.33, p=.003). These results suggest that aqua exercise is an effective strategy which has positive effects on body composition and blood components among elderly women. It might be possible to promote health condition in elderly women by implementing aqua exercise program which could be considered aging and excercise intensity.

• 대한근관절건강학회:학술대회논문집
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• 1999.11a
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• pp.339-344
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• 1999