• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2008년도 춘계 학술발표회 제20권1호
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• pp.1085-1088
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• 2008

철근공사에서 이음은 필연적으로 발생되며, 일반적으로 겹침이음을 통해 이음강도를 확보한다. 인장 이음길이는 인장 정착길이를 기준으로 산정되며, 정착길이는 실험적으로 도출된 부착강도 모델을 기반으로 결정된다. 인장이음은 휨을 받는 경우에 발생되므로 부재의 휨변형이 반드시 발생된다. 휨변형에의해 프라이(Prying) 거동이 발생되어, 철근이 피복콘크리트를 밀어내는 힘이 발생된다. 이러한 힘은 부착응력에 의해 발생되는 인장응력과 동일한 역할을 한다. 프라이 거동에 의해 발생된 인장응력과 부착응력에 의해 발생된 인장응력의 합이 콘크리트 인장강도에 도달하면 이음부가 파괴되므로, 프라이거동의 존재는 부착강도를 저하시키게 된다. 역학적 모델을 구성하여 휨부재의 인장이음에서 프라이거동이 이음강도에 미치는 영향을 분석하였다. 프라이 거동에 의한 인장응력은 보강근의 인장강도와 탄성계수에 비례하며, 휨부재의 휨강성에도 영향을 받는 것으로 나타났다. 또한 이음되는 보강근의 간격에 반비례하여 인장응력이 유발된다. 따라서 슬래브와 같이 휨강성이 작은 부재에 촘촘하게 이음된 경우에는 현행 설계기준보다 긴 이음길이를 확보할 필요가 있다.

• 한국생물물리학회:학술대회논문집
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• 한국생물물리학회 2003년도 정기총회 및 학술발표회
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• pp.38-38
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• 2003

The electrical properties of neurons are produced by the coordinated activity of ion channels (Hille, 1992). $K^{+}$ channels play a key role in shaping action potentials and in determining neural firing patterns. Small conductance $Ca^{2+}$-activated $K^{+}$ (S $K_{Ca}$ ) channels are involved in modulating the slow component of afterhyperpolarization (AHP) (Kohler et al., 1996). Here we examine whether rat type 2 S $K_{Ca}$ (rSK2) channels can affect the shape of the action potential and the neural firing pattern, by overexpressing rat SK2 channels in Aplysia neuron R15. Our results show that rSK2 overexpression decreased the intraburst frequency and changed the regular bursting activity of neurons to an irregular bursting or beating pattern in R15, Furthermore, the overexpression of rSK2 channels increased AHP and reduced the duration of the action potential. Thus, our results suggest that ectopic S $K_{Ca}$ channels play an important role in regulating the filing pattern and the shape of the action potential.ntial.

• The Korean Journal of Physiology
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• 제21권1호
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• pp.1-12
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• 1987

There is evidence that the effect of extracellular $Ca^{2+}$ on heart rate is temperature-dependent: at $38^{\circ}C$ excess $Ca^{2+}$ induces positive chronotropic response, whereas at $30^{\circ}C$ there is no significant chronotropic effect of $Ca^{2+}$. The cause of this temperature-dependency, however, remains still unclear. Therefore, this study was undertaken to investigate the chronotropic effect of external $Ca^{2+}$ at different temperature in the isolated rabbit atria and in the small strips of SA node cut perpendicularly to crista terminalis. In the isolated atria, the $Ca^{2+}$ effect was temperature-dependent: at $35^{\circ}C$ excess $Ca^{2+}$ evoked positive chronotropic response, while at $30^{\circ}C$ there was no significant changes in sinus rate. On the contrary, in the small SA strips external $Ca^{2+}$ induced negative chronotropic effect. At $35^{\circ}C$ changes in $Ca^{2+}$ concentration from 2 to 4, 6, and 10 mM decreased the sinus rate by $2.7{\pm}1.6%$, $11.2{\pm}3.7%$ and $23.2{\pm}8.1%$ respectively. Lowering the temperature to $30^{\circ}C$, the negative chronotropic effect of $Ca^{2+}$ became greater. With intracellular microelectrodes transmembrane potential was recorded in the small SA strips at $30^{\circ}C$, $35^{\circ}C$ and $38^{\circ}C$. As temperature increased from 30 to $38^{\circ}C$, sinus rate was accelerated by $13/min/^{\circ}C$, $APD_{50}$(action ptential duration from peak to 50% repolarization) decreased by $5\;msec/^{\circ}C$, and amplitude of action potential was slightly decreased. With an increase in $Ca^{2+}$ concentrations from 0.5 to 6 mM, overshoot increased and MDP decreased. These $Ca^{2+}$ effects on the overshoot and MDP of action potentials were not altered by temperature. But the $Ca^{2+}$ effects on the rates of diastolic depolarization, systolic depolarization and repolarization were modified by temperature. Discrpancy of the chronotropic effects of $Ca^{2+}$ between isolated atria and small SA strips was discussed.

• 약학회지
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• 제29권3호
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• pp.130-143
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• 1985

Bumetanide, when given intravenously in dogs, induced a potent diuresis with an increased amounts of sodium and potassium excreted in urine due to inhibition of reabsorbing them in renal tubule. Furthermore, clearances of osmolar substance and para-aminohippuric acid were increased, but clearace of free water diminished without any change of creatinine clearance. Bumetanide, administered directly into a renal artery, elicited diuresis only in the infused(experimental) kidney by the same mode of action as in the intravenous cases in renal function of the dog. Renal effects of intravenous bumetanide after pretreatment with the small dose of indomethacin (5.0mg/kg) revealed reduction only in clearance of paraaminohippuric acid. However the much dose of indomethacin (5.0mg/kg+5.0mg/kg/hr) or arachidonic acid showed a significant inhibition in the change rates of all renal function by bumetanide. Morover, pretreatment of probenecid also made a marked reduction in renal effects induced by bumetanide. From the above results, it is thought that bumetanide causes diuretic action due to dual mechanism inhibiting reabsorption of electrolytes in loop of Henle and increasing blood flow in kindney, that are provoked through the mediation of prostaglandins.

• Journal of information and communication convergence engineering
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• 제10권2호
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• pp.168-174
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• 2012

Flash is the most popular 2D animation and game development software, supporting vector and media technology at the core, which enables the development of small and pithy games. It is widely used in Web animation, courseware, TV commercials, game development, and other works of design. In this paper, we propose a control movement function and auxiliary functions for an alpine skiing game based on ActionScript 3.0. The control movement function is designed with moving phases (i.e., free fall, sliding, projectile, and landing). The auxiliary functions include drawing path, start/restart movement, and saving the highest score. In addition, for the visual design of our game, we designed animations in connection with a character and background. In order to facilitate testing the friction, users can input a chosen friction value. Without user input, the friction default is set at 0.97.

• 사상체질의학회지
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• 제2권1호
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• pp.213-221
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• 1990

Effect of Jeo Ryong-Tang water Extract on Renal Function in Rabbit and Dog. In order to investigate the Pharmacological action of Jeo Ryoung-Tang on renal function, this study was performed in rabbit and dog, making use of it's water extract. Jeo Ryoung-Tang water extract (JRWE), when given into ear vein of rabbits, produced diuresis in a small dose, but antidiuresis in a large dose. Diuretic action of JRWE accompanied the increase of glomerular filtration rate (GFR), renal plasma flow (RPF) and amounts of $Na^+$ in exdreated in urin, but fractional excretion of filtered $Na^+$ was not changed. JRWE, when injected into proleg's vein of dog, produced diuresis, At this time, changes of renal function were similar to that of diuresis in rabbit. JRWE, when infused into a renal artery of dog, exhibited the diuresis in both kidney. It is thought that JRWE, when given into vein of rabbit or dog, induces the diuresis, and the mechanism of it's diuresis is the increase of renal plasma flow through secondary action by some endogenous humoural substance.

• 생약학회지
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• 제14권1호
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• pp.9-16
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• 1983

Experimental studies were implemented to evaluate clinical efficacy of 'Daeshiho-Tang' and to validate Oriental medicine description of the recipe which has been widely used in metabolic diseases and febrile diseases. Following results were obtained; 1. Suppressive action was shown on convulsion due to cerebrocortical causes but no such action was noted either myelic or diencephatic causes in mice. 2. Analgesic and antipyretic actions were recognized in mice, rats and rabbits. 3. Antispasmodic actions were recognized on contraction of the ileum induced by $BaCl_2$ and histamine in mice and guinea-pigs. 4. Transport accelerating action of the small intestine was gained in mice.

• 대한한방내과학회지
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• 제15권2호
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• pp.197-208
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• 1994

In order to investigate the efficacy of Siljangsan by using the experimental animals, the action of gastric juice secretion, antiulcer. transport rates in the intestine and anti-cathartic action were studied. The following results were obtained. 1. Preventive effects on ulcer induced by pylorus-ligated and Ethanol-HCI were recognized 2. Suppression effects on gastric juice secretinon, free of acidity and total acidity were recognized, but pepsin output was not recognized. 3. For the transport ability of intestine of mice, the ability of small intestine was activated and large intestine was suppressed in the group administrated 4. Anti-cathatic action of mice induced by castor oil was recognized. According to above results, effect based on oriental medical reference was consistent with the actual experimental effect.

• 약학회지
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• 제18권1호
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• pp.39-48
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• 1974

Intravenously administered total water extract of Hoelen, (Pachymae fungus) in a dose of 10mg/kg and its methanol lextract, in a smaller dose than total water extract, produced significantly increase on urinary volume, sodium nad potassium excretion, and osmolar nad free water clearances. Increasing the doses produced more pronounced renal responses. Glomerular filtration rate and renal plasma flow changed littl with both extract. On the contrary, water extract from residue obtained on extraction with organic solvents exhibited no significant changes on the parameters of the renal function. In experiments, in which the total water extract was infused directly into a renal artery and urines from both ureters were collected separetely, a small dose of 0.3mg/kg/min showed no diuresis, but a large dose of 1.0mg/kg/min elicited diuretic action even on the contralateral kindneys. It is, therfore, concluded that Hoelen induces diuresis, mainly by inhibiting reabsorption of electrolytes in the renal tubules, and that the renotropic action may be mediated by some endogenous humoral substances.

• 약학회지
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• 제31권5호
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• pp.273-279
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• 1987

The effects of organic acidic drugs on the absorption, excretion and diuretic action of furosemide were studied. Cefalexin, p-aminohippuric acid (PAH), ibuprofen and p-amino salicylic acid (PAS) were selected as organic acidic drugs. The in situ absorption rate and absorption rate constant of furosemide (30$\mu{M}$) were significantly (p<0.05) decreased by 30$\mu{M}$ of cefalexin, PAH, ibuprofen and PAS in rat small intestine. The plasma concentration of furosemide was significantly (p<0.01) increased by cefalexin, PAH and ibuprofen in rabbits. But the urinary excretion rate, renal clearance and diuretic action of furosemide were significantly (p<0.05) decreased by cefalexin, PAH, ibuprofen and PAS in rabbits.