• 한국의류학회지
• /
• 제31권2호
• /
• pp.197-205
• /
• 2007

We investigated the effects of washing on the mechanical properties and hand values of spandex/cotton and cotton single jersey fabrics. These knitted fabrics were subjected to 30 laundering cycles with a drum-type washer and were followed by drying at $65^{\circ}C$ with a tumble dryer. The mechanical properties of the cotton knitted fabrics changed greatly during the first washing and then suffered no further change in their properties as the number of washing cycle increased. However, the properties of the spandex/cotton knitted fabrics changed continuously throughout all the washing cycles. The cotton/spandex knitted fabrics showed higher values in tensile and bending properties than did the cotton knitted fabrics, though both kinds of fabrics showed less difference in shearing, surface and compression properties. The spandex/cotton knitted fabrics which had proper density had a higher THV for winter underwear after 30 repeated washings than did the cotton knitted fabrics, and the THVs of both fabrics decreased with the increase in the number of washing cycles.

• 한국전문물리치료학회지
• /
• 제12권4호
• /
• pp.7-11
• /
• 2005

The purposes of this study were to investigate the effects of variability of training on the acquisition of motor skill of closed loop type tracking task using Rotary Pursuit, and to determine if there was a bilateral transfer effect to the non-dominant hand following practice with the dominant hand. Twelve healthy volunteer students (5 males and 7 females, aged 25 to 37) were randomly divided into a constant practice group and a variable practice group. A photoelectric rotary pursuit apparatus with stop clock and repeat cycle timer by Lafayette Instrumentation Co. was used for this study. Rotary pursuit is a closed loop task in which a subject attempts to keep a photoelectric stylus on a lighted target in motion. Subjects performed the clockwise circular pursuit task while standing. Experimental procedure was divided into three sessions, namely, pre-test, training, and post-test. The constant group practiced all 60 trials at 30 rpm. Variable practice group did a varied practice session with 15 trials at speeds of 20 rpm, 26 rpm, 34 rpm, and 46 rpm. No one in either group practiced with their non-dominant arm. A Mann-Whitney test and a Wilcoxon Signed Ranks test were used for statistical analyses. The results of this study showed no different training effect between groups on the post-test with the dominant hand. However, bilateral transfer effect of rotary pursuit task between hands was demonstrated. Possible mechanisms are discussed.

• 대한설비공학회지:설비저널
• /
• 제17권4호
• /
• pp.357-368
• /
• 1988

An application of thermal response coefficient method for obtaining thermal load on stud-frame walls in a typical house is presented. A set of stud-frame walls is two-dimensional heat conduction transients with composite structure. The ambient temperature on the right-hand face of the stud-frame walls is a typical day-cycle input and the room temperature on the left-hand face is a constant input. The desired output is thermal load at the left-hand face. The time-dependent ambient temperature is approximated by a continuous, piecewise-linear function each having one hour interval. The conduction problem is spatially discretized as 8 computer modelings by finite elements to obtain thermal response coefficients. The discretization and round-off errors can be neglected in the range of adequate number of nodes. A 60-node discretization is recommended as the optimum model among 8 computer modelings. Several sets of response coefficients of the stud-frame walls are generated by which the rate of heat transfer through the walls or some temperature in the walls can be calculated for different input histories.

• 대한전자공학회:학술대회논문집
• /
• 대한전자공학회 1998년도 추계종합학술대회 논문집
• /
• pp.755-758
• /
• 1998

As the performance of microprocessor improves, the design complexity grows exponentially. Therefor, it is very important to make the bug-free model as early as possible in a design life-cycle. This paper describes the simulation-based functional verification methodology for the RTL level description model. It is performed by multi-stage verification methods using extensive hand-generated self-checking tests supplemented with random tests. This approach is opplied to the functional verification of the GPU processor of Raptor and various bugs are detected.

• 콘크리트학회논문집
• /
• 제15권2호
• /
• pp.163-172
• /
• 2003

최근 콘크리트 구조물이 점차 대형화, 고층화, 장대화 및 특수화 됨에 따라 강섬유 콘크리트의 적용이 요구되고 있다. 본 연구에서는 반복하중을 받는 강섬유를 혼입한 2경간 연속보에 대한 실험적 연구를 수행하여 피로하중에 의한 강섬유 혼입율(0%, 0.75%, 1.00%, 1.25%)에 따른 피로강도를 규명하고자 하였다. 정적실험을 통하여 극한하중, 초기 휨균열하중 등을 측정하였고 하중과 철근의 변형율 관계, 하중과 처짐 관계 그리고 하중증가에 따른 균열성장과 파괴양상 등을 관찰하였다. 피로실험을 통하여 반복횟수와 처짐 관계, 반복횟수와 변형율 관계 그리고 반복횟수에 따른 균열성장과 파괴양상을 관찰하였다. 피로실험 결과 강섬유를 혼입하지 않은 2경간 연속보는 정적극한강도의 60~70%에서 파괴되었고 S-N곡선으로부터 반복횟수 200만회에 대한 피로강도는 정적극한강도의 67.2% 전후임을 확인 할 수 있었다. 또한, 강섬유를 혼입한 2경간 연속보는 정적극한강도의 65∼85%에서 파괴되었고 S-N곡선으로부터 반복횟수 200만회에 대한 피로강도는 정적극한강도의 71.7%전후임을 확인할 수 있었다.

• Journal of Periodontal and Implant Science
• /
• 제33권3호
• /
• pp.415-437
• /
• 2003

Ginseng Radix(GR) had been used widely from oriental medicine and the effects of it have been investigated by many researchers. The purpose of present study was to investigate the effects of GR on the cell cycle progression and its molecular mechanism in human fetal osteoblast. The results were as follows. Increased cell proliferation was observed in cells exposed to 100 ng/ml, 10 ng/ml of GR-1 at 12 hours and 24 hours, 1 ${\mu}g$/ml of GR-1 at 48 hours, and 100 ${\mu}g$/ml, 10 ${\mu}g$/ml of GK-2 at 12 hours, all treatment groups of GR-2 at 24 hours(p<0.05). S phase and G1 phase was increased in the group of treated with 100 ng/ml of GR-1, with 10 ${\mu}g$/ml and 1 ${\mu}g$/ml of GR-2, with 100 ${\mu}g$/ ml and 10 ${\mu}g$/ml of GR-3 in the cell cycle analysis. The cell cycle regulation protein levels of Cyclin D1, Cyclin E, CDK 2. CDK 4 and CDK 6 were increased in the group of treated with 1 ${\mu}g$/ml and 100 ng/ml of GR-1, with 10 ${\mu}g$/ml and 1 ${\mu}g$/ml of GR-2, with 100 ${\mu}g$/ ml and 10 ${\mu}g$/ml of GR-3. On the other hand, p21 was decreased in the treatment group with 1 ${\mu}g$/ml and 100 ng/ml of GR-1, with 10 ${\mu}g$/ml and 1 ${\mu}g$/ml of GR-2, 10 ${\mu}g$/ml of GR-3, and p53 and p16 was decreased in the treatment group with 100 ng/ml of GR-1, 100 ${\mu}g$/ml and GR-3 and pRb was decreased in the all treatment groups except 1 ${\mu}g$/ml of GR-1. These results suggested that GR increases the cell proliferation and the cell cycle progression in human fetal osteoblast, which is linked to increased cell cycle regulation protein levels of Cyclin D1 , Cyclin E, CDK 2, CDK 4, CDK 6 and decreased cell cycle regulation protein levels of p21, pRb.

• 한국발생생물학회지:발생과생식
• /
• 제16권4호
• /
• pp.279-287
• /
• 2012

We investigated the changes in plasma sex steroid hormones, testosterone (T), estradiol-$17{\beta}$ ($E_2$), 17,$20{\beta}$-dihydroxy-4-pregnen-3-one ($17{\alpha}20{\beta}P$), 11-ketotestosterone (11KT) and cortisol levels from ribbed gunnel, Dictyosoma burgeri in associated with annual reproductive cycle. The gonadosomatic index (GSI) of females increased from November, peaked in February and decreased rapidly from March. The GSI of males also increased from November, peaked in January and then decreased gradually. In females, $E_2$ levels increased and remained high from December to February. The levels of T showed a similar tendency and correlated ($r_s$=0.898, p<0.01) with $E_2$ levels. The levels of $17{\alpha}20{\beta}P$ increased rapidly in February ($4.78{\pm}1.01ng/ml$) and peaked in July ($5.08{\pm}0.65ng/ml$). Cortisol level was peaked in March and correlated with $17{\alpha}20{\beta}P$ levels ($r_s$=0.696, p<0.01). In males, the levels of T was peaked in January and then decreased rapidly. The levels of 11KT were remained high from October to January. On the other hand, the levels of $17{\alpha}20{\beta}P$ fluctuated during reproductive cycle. These results suggest that plasma sex steroids in ribbed gunnels have annual periodicity, and that cortisol may involve in maturation of females.

• Reproductive and Developmental Biology
• /
• 제32권2호
• /
• pp.89-95
• /
• 2008

The present study was undertaken to identify changes of plasminogen activators (PAs) in porcine oviductal epithelial cells (POECs) during the estrous cycle classified with post-ovulatory stages (Post-Ov), early to mid-luteal stages (Early-mid L) and pre-ovulatory (Pre-Ov) stages. The urokinase-type plasminogen activator (uPA) was only observed on day 5 and day 7 of culture in the POECs on all the estrous cycles and gradually increased according to increasing culture times, but not Early-mid L. In POECs-conditioned medium, uPA, tissue-type (tPA) and tPA-PA inhibitor (tPA-PAI) activity were observed at all culture times during estrous cycles. The uPA activity of POECs-conditioned medium on Post-Ov stage were significantly (p<0.05) decreased during prolonged cultures. On the other hand, the tPA activity of POECs-conditioned medium at Post-Ov stage was significantly (p<0.05) higher on day 5 than compared to the other days. Although was higher on day 1 at Post-Ov stage, the tPA-PAI activity of POECs-conditioned medium was significantly (p<0.05) higher on day 7 at all stage than that of day 5 of the culture. Taken together, these results suggest that uPA, tPA and tPA-PAI are produced by POECs, and the variations of the PAs activity are regulated in the different stages of the estrous cycle.

• 한국수산과학회지
• /
• 제30권1호
• /
• pp.132-138
• /
• 1997

동해안 한해성 조개인 북방대합의 자원 증대를 위한 기초 자료를 얻기 위하여 1994년 3월부터 1995년 5월까지 주로 조직학적 방법에 의해 생식소의 발달과정과 생식주기를 조사하였다. 북방대합은 자웅이체로서, 생식소는 해부학적으로 소화맹낭과 족부 근육 사이에 위치하였다. 비만도는 1994년 6월에 0.19로 가장 높았으며 11월에 최소값을 보였다. 생물학적 최소형은 각장 50.0mm였으며, 80.0mm 이상의 대형개체에서도 $10\%$ 미만의 성적으로 미분화한 개체가 관찰되었다. 성숙한 난모세포의 크기는 $50\~60{\mu}m$였으며, 성숙기의 정소에서 정소란이 관찰되었다. 북방대합의 생식주기는 분열증식기 ($10\~1$월), 성장기 ($2\~4$월), 성숙기 ($4\~6$월), 산란기 ($6\~7$월) 및 휴지기 ($8\~9$월)의 연속적인 5단계로 구분되었다.

• 한국건축시공학회지
• /
• 제14권6호
• /
• pp.583-590
• /
• 2014

본 연구에서는 경제적인 창호공사 방안을 확인하기 위해 단열필름이 시공된 창호유리와 일반유리의 생애주기비용을 분석하여 비교하고자 하였다. 이를 위해 Window 6.3과 ECO2-OD 시뮬레이션 프로그램을 사용하여 유리 유형별 창호의 열성능 데이터를 측정하고 사례 건물에 적용하여 냉 난방 유지비용 및 LCC를 산출하여 경제성을 비교하였다. 연구결과 단열필름을 추가적으로 시공함으로써, 냉 난방 유지비용 측면에서는 하절기 태양열이 실내로 투과하는 것을 막아 냉방비용 절감 효과가 있지만, 이로 인해 동절기에는 난방비용이 증가하는 것으로 나타났다. 생애주기비용 측면에서 볼 때, 냉방비용 절감 효과가 난방비용 증가량과 필름 시공 및 수선으로 발생하는 추가비용을 상쇄하지 못하기 때문에 단열필름의 시공은 적절한 방법이 아니라고 할 수 있다.