• 한국운동역학회지
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• 제16권2호
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• pp.97-108
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• 2006

C. H. OH, S. N. CHOI, T. G. NAM, The Kinematic Analysis of the Tennis Flat Serve Motion, Korean Jiurnal of Sports Biomechanics, Vol. 16, No. 2, pp. 97-108, 2006. By the comparison and the analysis of the different factors during the tennis flat serve motion such as the required time per section, the movement displacement of the racket, the velocity of the upper limbs joints, the physical center of gravity, and the angle and the angular velocity of the upper limbs joints between an ace player and a mediocre player, these following results were drawn. First, the experiment result of the total time required per section in a tennis flat serve motion showed that an ace player was faster than a mediocre player by 0.4 seconds. This result suggested that it was required to increase the speed of the racket head by a swift swing to perform an effective flat serve motion. Second, the experiment result of the movement displacement of the racket in the tennis flat serve motion showed that an ace player greatly moved toward the left side on an x-axis. But both an ace and a mediocre player were shown to be at the similar points on a y-axis at the moment of the impact of the racket. An ace player was also shown to be located at a higher position on a z-axis by 0.23m. Third, the velocity of the center of gravity of an ace player was faster in every phase than that of a mediocre player in a tennis flat serve motion. Fourth, the velocity of the upper limb joints of an ace player was faster in every phase than that of a mediocre player in a tennis flat serve motion. Fifth, the experiment result of the speed of the racket head in tennis flat serve motion showed that a mediocre player was faster than an ace player in the first phase, but the latter was faster than the former in the second, third, and the fourth phases. Sixth, at the moment of impact of a tennis flat serve, an ace player had greater flexion of the angle of the wrist joints by an 11.8 degree than a mediocre player. An ace player also had greater extension of the angle of the elbow joint and the shoulder joint respectively by a 5.2 degree and a 1.4 degree with a mediocre player. Seventh, an ace player had greater angular velocity of the upper limb joints and the hip joints than a mediocre player at the moment of the impact of tennis flat serve. Eighth, an ace player was shown to have a greater change of the forward and the backward inclination (or the anterior and posterior inclination) of the upper body

• 한국운동역학회지
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• 제17권1호
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• pp.29-39
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• 2007

This study were obtained elapsed time phase-by-phases, displacement, user angle, velocity and angular velocity to analyse kinematically contributing factors at impact of forehand drive motion, on targeting three male players. The results of the study were presented as follows; In the forehand drive swing, the elapsed time by phases was a total of .52 seconds: .30 seconds from backswing to impact and .22 seconds from impact to follow-through, Considering the mean change in locations of COM of each(part$\rightarrow$body segment) at impact, racket head, left shoulder, right wrist and left hip, the left-right directions(X-axis) were showm to be each $.61{\pm}.03$, $1.19{\pm}.08$, $.66{\pm}.03$, $.94{\pm}.06$, and $.45{\pm}.03m$. The displacement differences of COM of each body segment were shown to be -.57, -.05, -.33, and .16m. For the vertical direction(Z-axis), the center of mass was lowest at impact and highest at E3. For the displacement of the right wrist on the left hip, the right wrist moved to .82m to the lower direction without change in the locations of the hip from E1 from E2. When the left hip moved .02m from E2 to E3, the right wrist moved .7m in the upper direction. In respect to the velocity of each body segment, the hip and the shoulder joint accelerated and then the wrist followed. Then the right wrists of all the subjects and their racket heads showed maximum speed, and an effective swing was observed. At the angle of each part, the angle of the right wrist was the smallest at the backswing and the largest at the moment of the impact. Then it increased gradually in the follow-through section. In respect of angular velocity for subject A, the hip moved and the largest change occurred. Immediately before the impact, the subject made a swing using his right wrist, his hip, and the shoulder joint, showing the maximum value, which was judged to be effective.

• Journal of Radiation Protection and Research
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• 제41권3호
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• pp.196-205
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• 2016

Background: The emergency planning zone (EPZ) of the city of Busan is divided into the precautionary actions zone (PAZ) and the urgent protective action planning zone; which have a 5-km radius and a 20-km to 21-km radius from the nuclear power plant site, respectively. In this study, we assumed that a severe accident occurred at Shin-Kori nuclear unit 3 and evaluated the dispersion speed of radiological material at each distance at various wind speeds, and estimated the effective dose equivalent and the evacuation time of PAZ residents with the goal of supporting off-site emergency action planning for the nuclear site. Materials and Methods: The total effective dose equivalent, which shows the effect of released radioactive materials on the residents, was evaluated using the RASCAL 4.2 program. In addition, a survey of 1,036 residents was performed using a standardized questionnaire, and the resident evacuation time according to road and distance was analyzed using the VISSIM 6.0 program. Results and Discussion: According to the results obtained using the VISSIM and RASCAL programs, it would take approximately 80 to 252.2 minutes for permanent residents to move out of the PAZ boundary, 40 to 197.2 minutes for students, 60 to 232.2 minutes for the infirm, such as elderly people and those in a nursing home or hospital, and 30 to 182.2 minutes for those temporarily within the area. Consequently, in the event of any delay in the evacuation, it is estimated that the residents would be exposed to up to $10mSv{\cdot}h^{-1}$ of radiation at the Exclusion Area Boundaries (EAB) boundary and $4-6mSv{\cdot}h^{-1}$ at the PAZ boundary. Conclusion: It was shown that the evacuation time for the residents is adequate in light of the time lapse from the initial moment of a severe accident to the radiation release. However, in order to minimize the evacuation time, it is necessary to maintain a system of close collaboration to avoid traffic congestion and spontaneous evacuation attempts.

• 생물정신의학
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• 제2권2호
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• pp.205-217
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• 1995

1) Paroxetine이 5-HT흡수에 가장 강력하고, 선택적이었으며, 그 다음이 fluvoxamine, sertraline, fluoxetine순이었고, sertraline은 다른 SSRIs와는 달리 NE보다 DA억제작용이 더 강했다. 2) Paroxetine이 muscarinic cholinergic 수용체에 대한 친화력이 다소 높았을 뿐, 전반적으로 SSRIs는 histamine $H_1$과 ${\alpha}_1$에 대한 친화력은 약했다. 3) Paroxetine은 ${\beta}$-adrenoceptor와 cyclic AMP에 영향을 미치지 않는 반면, sertraline은 ${\beta}$-adrenoceptor와 cyclic AMP의 감소를 가져왔다. 4) SSRIs의 생체이용율은 대략 50%이었으며, 투약후 2~8시간 사이에 최고혈중농도에 도달하였으며, 특히 sertraline은 음식물과 같이 복용시 혈장의 concentration time curve와 최고 농도를 증가시켰다. 5) Sertraline은 혈중농도가 용량에 비례하였으며, 모든 SSRIs는 비교적 큰 용량분포를 보이고, 높은 비율로 혈장 단백질과 결합되어 있었다. 6) Fluoxetine 대사물의 5-HT 억제 작용이 제일 강했다. 그러나 paroxetine, fluoxetine, sertraline 대사물은 강도는 서로 다르지만 간의 isoenzyme IID6를 억제하며, 그 중에서 paroxetine의 억제작용이 제일 강력하다. 7) Sertraline은 TCAs나 haloperidol과 병합사용시 TCAs나 haloperidol의 혈중농도의 유의한 변화가 없었으며, MAOI A형인 moclobemide와 비교적 안전하게 병용 치료할 수 있다. 8) SSRIs는 TCAs와 비교해볼 때 치료효과는 유사하였으나 fluvoxamine은 자살사고에, paroxetine은 우울중에서 나타나는 불안과 운동성 초조증에 효과적이다. 9) 급성 우울증 삽화시 현저한 효과를 보인 후 적어도 4개월 이상의 유지치료기간이 필요하다. 10) SSRIs는 위장관계통의 부작용이 가장 많았고, 부작용은 일반적으로 분복한 경우가 적었다.

• The Journal of Korean Physical Therapy
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• 제10권1호
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• pp.1-6
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• 1998

효율적으로 국소마취를 유발시키는 procaine이온도입의 효과적인 농도를 조사하였다. 19세에서 34까지의 자원자 45명을 9명씩 무작위로 5군으로 나누어 배치하고, 각군 대상자의 오른쪽 전완 전면에 각각 $2\% (pH\;5.2H),\;4%(pH\;5.12),\;8\%(pH\;4.98),\;16\%(pH\; 4.72),\;32\%(pH\;4.52)$ 염산 procaine용액 2ml를 적신 $3.5\times3.5 cm$의 면패드를 대고 4mA로 10분간 양극 직류전류를 통전시켰다. 이온도입 직후부터 5분 간격으로 21 G주사침으로 이온도입부위를 1mm함몰되게 눌러 바늘로 찌르는 통증을 느낄 때까지 감각검사를 시행하여 국소마취지속시간을 측정하였다. Procaine의 농도에 따른 축소마취지속시간을 일원분산분석한 결과 유의한 차이를 보였으며 (F=5.83; df=4, 40; p<.001). 이를 사후검정한 결과 농도 $4\%$의 국소마취지속시간이 농도 $2\%,\;8\%,\;16\%,\;32\%$보다 유의하게 길었다 (p<.01). 또한 상관분석 결과 약물의 농도는 국소마취지속시간과 상관관계가 없었다 (r=-0.41, NS). 본 연구 결과 $4\%$ 농도의 염산 procaine 용액의 이온도입이 국소마취지속시간을 가장 길게 유지하여 $4\%$ 염산 procaine 용액이 이온도입에 가장 효과적인 농도였음을 알 수 있었다.

• Journal of Nutrition and Health
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• 제36권1호
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• pp.24-31
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• 2003

The present study was attempted to investigate the antioxidant capacity of popular yellow-green vegetable juices (kale, Angelica keishei, carrot, small water dropwort) and to investigate the effect of vegetable juices on protecting oxidative damage to DNA in cultured Chinese hamster lung (CHL) cells. Antioxidant capacity was analyzed by TRAP assay (Total radical-trapping antioxidant potential). Cellular DNA dmamage was measured by SCGE (single-cell gel electrophoresis, also known as comet assay. Cells incubated in medium with PBS (negative control) or with various concentration of the freeze dried green juices (25, 50, 100, 250 $\mu\textrm{g}$/$m\ell$) resuspended in PBS were treated with $H_2O_2$ (200 ${\mu}{\textrm}{m}$) as an oxidative stimulus for 5 min at 4$^{\circ}C$. The physiological function of each vegetable juice on oxidative DNA damage was analyzed and expressed as tail moment (tail length X percentage migrated DNA in tail) . Kale juice had the highest TRAP value suggesting that kale has the highest antioxidant capacity followed by Angelica keishei, small water dropwort and carrot. Cells treated with $H_2O_2$ had extensive DNA damage compared with cells treated with PBS or pre-treated with vegetable juice extracts. All green juices inhibited $H_2O_2$-induced DNA damage with kale being the most effective juice among the tested juices. These results indicate that green juice supplementation to CHL cells followed by oxidative stimulus inhibited damage to cellular DNA, supporting a protective effect against oxidative damage induced by reactive oxygen species. (Korean J Nutrition 36(1) : 24-31, 2003)

• Structural Engineering and Mechanics
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• 제72권5호
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• pp.631-642
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• 2019

The objective of the present study is to examine the flexural behavior of two-span post-tensioned lightweight aggregate concrete (LWAC) beams using unbonded tendons and the reliability of the design provisions of ACI 318-14 for such beams. The parameters investigated were the effective prestress and loading type, including the symmetrical top one-point, two third-point, and analogous uniform loading systems. The unbonded prestressing three-wire strands were arranged with a harped profile of variable eccentricity. The total length of the beam, measured between both strand anchorages, was 11000 mm. The test results were compared with those compiled from simply supported LWAC one-way members, wherever possible. The ultimate load capacity of the present beam specimens was evaluated by the collapse mechanism of the plasticity theorem and the nominal section moment strength calculated following the provision of the ACI 318-14. The test results showed that the two-span post-tensioned LWAC beams had lower stress increase (Δf_ps) in the unbonded tendons than the simply supported LWAC beams with a similar reinforcement index. The effect of the loading type on Δf_ps and displacement ductility was less significant for two-span beams than for the comparable simply supported beams. The design equations for Δf_ps and Δf_ps proposed by ACI 318-14 and Harajli are conservative for the present two-span post-tensioned LWAC beams, although the safety decreases for the two-span beam, compared to the ratios between experiments and predictions obtained from simply supported beams.

• Asian-Australasian Journal of Animal Sciences
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• 제24권10호
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• pp.1365-1371
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• 2011

The intensity and duration of sexual behavior in Bos indicus was assessed through the continuous observation of sexual receptivity. Two groups of cows were formed: only synchronized (n = 50) and other group further superovulated (n = 20). An intravaginal implant that released progesterone over 9 d was used. After removing the implant, 25 mg of $PGF_{2{\alpha}}$ was administered. In the superovulated group, the administration of 280 mg (Follicle stimulant hormone) FSH-P1 per cow with a decreasing dosage over 4 d was utilized. In both groups, behavioral observations began at the moment of implant removal. Sexual behavior was analyzed using a Kruskal-Wallis test to compare the mean of hours in estrus, effective mountings and number of mounts/hour during estrus. A nonparametric survival analysis was performed using the time in two ways: i) when an event happened it was placed in a 24 h timeframe and, ii) the time of observation in continuous form (96 h) assessing the difference between curves by the log rank test Chi-square. The only significant difference was the number of mounts/h during receptivity (p<0.05). In the superovulated group three periods of sexual activity during the day were identified, with these events being of greater frequency and duration than the synchronized group (p = 0.02); besides, the superovulated group began estrus before the synchronized group (p = 0.0035) when using the total period. In a simulation study, when the number of observations went from two (06:00-18:00) to three periods (06:00, 12:00 and 18:00) cows detected accurately (<6 h after the onset) increased more than 20%. The results show that superovulated cows presented greater intensity and duration of sexual activity in contrast with only synchronized animals.

• 한국산학기술학회논문지
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• 제16권9호
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• pp.6160-6168
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• 2015

의료기관 종사자의 손 위생 수행은 의료관련 감염의 전파를 예방하는 가장 효과적인 방법이다. 본 연구는 직종별 손 위생 수행 측정과 분석을 위해 세계보건기구(WHO)의 손 위생 수행 평가도구를 이용한 직접관찰방법으로 2010년 10월 25일부터 12월 31일까지 수행되었으며, SPSS 21.0으로 기술분석, 교차분석, 다중로지스틱분석을 하였다. 총 8,644 건의 손 위생 상황이 관찰되었고, 손 위생 수행률은 94.1%였으며 의사가 가장 낮았다(83.3%; OR:0.209, 95%CI:0.174-0.252). 직종별 수행률(p<0.001), WHO에서 권고하는 5개 상황(WHO's 5Moments)별 수행률은(p<0.001) 유의한 차이를 보였으며, 간호사(p=0.003)와 의료기사직(p<0.001)이었다. 본 연구결과 손 위생 수행률 향상을 위한 직종별 특성화된 손 위생 전략과 WHO's 5Moments에 따라 차별화된 전략 개발이 필요할 것으로 사료된다.

• 한국산학기술학회논문지
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• 제15권10호
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• pp.6329-6335
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• 2014

스트럿-타이 모델에서 절점 폭은 해석과 설계에서 중요하다. 그것은 트러스 유사 시스템에서 힘의 분포에 영향을 준다. 또한, 설계 코드를 만족시키기 위한 모든 스트럿 및 절점의 검증에도 영향을 미친다. 여기서 코드는 ACI-318 코드를 의미한다. 절점 폭을 결정하는 4가지 방법이 있다. 즉 1)유효 깊이를 보 높이의 0.9배로 가정하는 방법 2)모멘트 평형을 이용하는 방법 3)절점 폭을 380mm로 가정하는 방법 그리고 4)본 연구에서 제안된 방법이다. 106개의 파라미터 연구를 분석하였다. 그 결과 필요로 하는 총 강재량이 4가지 방법 모두 크게 차이가 나지 않기 때문에 가장 쉬운 방법으로 선택하는 것이 시간 절약 측면에서 좋을 것으로 판단된다.