• 대한약리학회지
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• 제31권2호
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• pp.195-206
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• 1995

The study was undertaken to examine the possibility of the involvement of $K^+$ channels in the mechanism of relaxant-action of imipramine on the isolated canine detrusor muscle strips. Canine urinary bladder were isolated, and smooth muscle strips of 15 mm long and 2 mm wide from the mid-portion of anterior wall were made in the Tyrode solution of $0{\sim}4^{\circ}C$. The strips were prepared for isometric myography in Biancani's isolated muscle chamber containing 1 ml of Tyrode solution, which was maintained with pH 7.4 by aeration with $95%\;O_2/5%CO_2\;at\;37^{\circ}C$. RP 52891, a non-specific $K^+$ channel opener, concentration-dependently suppressed the spontaneous phasic contractions of the detrusor strips. Imipramine, a tricyclic antidepressant, also reduced the spontaneous contractions in a concentration-dependent manner. RP 52891 was more potent than imipramine(p<0.05), and Imipramine was more efficient than RP 52891(p<0.05).Procaine, a voltage-dependent $K^+$ channel blocker, glibenclamide, an ATP-dependent $K^+$ channel blocker, and apamin, a calcium-dependent $K^+$ channel blocker antagonized the relaxant effect of RP 52891, but not of imipramine. Imipramine reduced the electric field stimulation (EFS) -induced contractions concentration-dependently. None of the $K^+$ channel blockers employed for this study, procaine, glibenclamide or apamin antagonized the inhibitory action of imipramine on the EFS-induced contraction. These results suggest that in canine detrusor, the $K^+$ channels of the characteristics of voltage-dependent, ATP-dependent and/or calcium-dependent are exist, and the inhibitory action of imipramine on the contractility of the detrusor is independent from the $K^+$ channels.

• 한국자기학회:학술대회 개요집
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• 한국자기학회 1998년도 춘계연구발표회 논문개요집
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• pp.64-65
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• 1998

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 1996년도 봄 학술발표회 논문집
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• pp.47-64
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• 1996

• 한국주조공학회지
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• 제18권5호
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• pp.462-466
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• 1998

Interest in rapid solidification of magnesium alloys stems from the fact that conventional ingot metallurgy alloys exhibit poor strength, ductility, and corrosion resistance. Such properties can be improved by microstructural refinement via rapid solidification processing. Mg-5wt%Zn alloys have been produced as continuous strips by melt overflow technique and the strips were consolidated by hot extrusion. The yield stress, tensile strengh and ductility obtained in asextruded Mg-5wt%Zn alloy were ${\sigma}_{0.2}=152\;MPa$, ${\sigma}_{T.S{\cdot}}=263\;MPa$ and ${\varepsilon}=21.8%$. In order to evaluate the influence of additional elements on mechanical properties, Th and Zr were added in rapidly solidified Mg-5wt%Zn alloy. An 130% increase in yield stress of as-extruded Mg-5wt%Zn-3wt%Th-1wt%Zr alloy was attributed to grain refinement by rapid solidification and elemental addition.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2000년도 봄 학술발표회논문집
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• pp.61-68
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• 2000

In general, the design of membrane structures takes three steps. The first is shape finding analysis which is determination of initial equilibrium geometry with uniform stresses. The second step involve the computation of the stress-deformation to get completed membrane under various load conditions. The third step is to divide the membrane structures into several plan strips from the initial equilibrium states. This procedure is needed because of the initial shape has usually undevelopable curved surface and is called as "cutting patterns generation". By introducing this work, the deformation due to the initial stress is removed and approximate cutting patterns are generated. In this approach, however, material properties is not considered, therefore the error between the design stresses and actual stresses during the fabrication of plan strips should be occurred. In this paper, actual equilibrium shape analysis procedure for HP shape models is presented. The deviations of stresses between the design stresses and actual stresses are estimated.

• 대한의용생체공학회:의공학회지
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• 제16권2호
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• pp.139-148
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• 1995

In this paper we report the device of a multi-channel clinical instrument developed for determi¬nation of the levels of the urinary urobilinogen, glucose, ketone, bilirubin, protein, ascorbic acid, nitrite, pH, occult-blood, specific gravity, and leukocytes semiquantitatively. The test parameters are expressed on the dry test strips as a range of color intensities by chemical reactions. The instrument measures the value of each substance by reading the reflectance light emanated from the test strips. We also designed the reagent strip cassette and loader in order to intercept the outside interference. The loader can be operated semi-automatically. The light source is consisted on light emitting diodes at three specific wavelengths (560 nm, 610 nm, 650 nm). Precision of the system was evaluated by testing a series of commercial control urine samples. Furthermore, the performance of the instrument was compared with two other test methods on the urine samples from 100 persons. Our results showed a good repeatability between tests and a satisfactory agreement between the readings by our instrument and visual evaluation.

• 센서학회지
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• 제21권6호
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• pp.408-412
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• 2012

An in-line dispersive delay line (DDL) demands low and controllable reflectivity of the reflectors, especially if the surface acoustic wave (SAW) propagates all the way along the reflecting structure. The metal reflectors are usually too strong and introduce too much attenuation in such a device. The proposed solution of this problem is to spatially separate the acoustic channels for different frequencies with the help of Fan-shaped Transducers (FIDT) and to use narrow open metal reflectors to reduce reflectivity. Special arrangement of FIDT is performed to use 180-deg. reflection of the SAW. Narrow open metal strips with a metallisation ratio of the order of 20% are used as reflectors with small and controllable reflectivity. Reflectivity of such strips is estimated both theoretically and experimentally. Experimental performance of the proposed DDL is presented.

• Journal of Pharmaceutical Investigation
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• 제7권1_4호
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• pp.28-37
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• 1977

The pharmacological actions to methanol extract(PME) obtained from Plantaginis semen were examined in the rabbit. 1) PME, when administered into the vein of rabbit, produced the fall of blood pressure and stimulation of respiration. The former action was inhibited by atropine but the latter not affected by atropine. 2) PME caused contraction in both isolated intestinal and uterus strips, atropine blocked the contraction of intestinal strips while did not the uterus contraction. 3) PME decreased the heart rate of rabbit anesthetized with urethane. 4) PME elicited antidiuresis with doses ranging from 10mg/kg. The antidiuresis appeared to be related to the hemodynamic changes decreases in the renal plasma flow and glomerular filtration rate. Urinary sodium and potassium decrease in the renal plasma flow and glomerular filtration rate. Urinary sodium and potassium decrease in relation to the diminished filtration.

• Journal of Electrical Engineering and Technology
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• 제6권6호
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• pp.849-852
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• 2011

This paper investigates a method to tackle the resonance problems of the rectangular power-bus structure(PBS) using thin sheets loaded with periodic metal strips. The equivalent surface impedance of the proposed loading is calculated and involved in the expression of the impedance that accounts for in the PBS, in order to improve the resonance behavior of the original structure. The effects of the strips and the immediate surroundings are illustrated by a number of numerical experiments. Also the restrictions of the technique are addressed.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2007년도 춘계학술대회논문집
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• pp.71-74
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• 2007

The objective of this presentation is to introduce a recent development of a magnetostrictive grating technique using an optimal yoke to efficiently generate and measure SH (Shear-Horizontal) waves in a plate. Gratings are effective means to generate frequency-tuned waves, but the gap between magnetostrictive gratings inevitably obstructs magnetic flow. Because magnetic field is the main physical quantity to actuate and sense ultrasonic waves, the transducer performance is most significantly influenced by the magnetic field distribution in the strips. Thus, wave transduction efficiency can be substantially improved if better magnetic flow is formed in the strips. To improve the efficiency, the topology optimization method was used to determine an optimal yoke configuration. A series of experiments on an aluminum plate were conducted using a grating with and without the designed yoke; when the yoke was used, the signal outputs increased up to 60 %.