• Korean Journal of Veterinary Research
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• v.13 no.1
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• pp.35-38
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• 1973

It was discovered that furamizole, one of the nitrofuran derivatives, possesses a strong antibacterial activity upon various organisms. Since then, a number of nitrofuran derivatives have been examined for antibacterial activity. This experiment was carried in vitro to evaluate with regard to antibacterial activity upon Mycoplasma gallisepticum. As a result, furamizole was found to be a good effective compound upon Mycoplasma gallisepticum. Furamizole inhibited the growths of the three strains of Mycoplasma gallisepticum and two strains of the same species at a concentration of $0.064{\mu}g/mI$. and $0.016{\mu}g/mI$. In short, there were not great differences in sensitivity to furamizole among the five strains tested.

• Applied Biological Chemistry
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• v.28 no.2
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• pp.82-87
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• 1985

Aiming at the improvement of accuracy and sensitivity of gibberellin analysis by gas chromatography-selected ion monitoring (GC-SIM), the mass spectra of two types of 29 gibberellin derivatives, methyl ester-trimethylsilyl ethers and trimethylsilyl ester-trimethylsilyl ethers, were obtained and their advantages and disadvantages in GC-SIM analysis are discussed.

• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.575-578
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• 2009

Pentacene has excellent semi-conducting characteristics. But pentacene practically used in OTFTs gives rise to problems mainly due to its sensitivity to oxygen and its very low solubility. In order to make up the problems, 6,13-disubstituted pentacene derivatives were synthesized and characterized. The properties of the compounds were characterized by FT-IR, NMR spectroscopy and UV-visible spectrophotometer. Now we are measuring the charge transport mobility and the on/off current ratios.

• The Korean Journal of Pharmacology
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• v.12 no.1
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• pp.15-22
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• 1976

The clinical abuse of C.N.S. stimulants during recent years has directed particular attention. Effect of various organs other than C.N.S. was also extensively investigated with those agents. It has been shown that, although there is a wide variation in sensitivity between species, caffeine stimulates gastric secretion in man, cat, guinea pig and dog. Roth and Ivy(1944) reported that caffeine and histamine acted synergistically in stimulating gastric secretion in the cat. Vaille et al(1966) studied that production of pancreatic juice in the rat was enhanced, but bile secretion was not affected by caffeine. In clinical study the effect of chlorpromazine on the external pancreatic secretion in the 24 subjects, the volume fell more than 20% in 7 subjects. (Skajaa et al 1960) It is widely known that C.N.S. stimulants enhanced spontaneous motor activity in the mice, while tranquilizers depressed the activity. Woo (1975) reported that the group of mice treated with chlorpromazine showed markedly inhibited motor activity and in the group of mice treated with amphetamine, there was a significant increase in the motor activity. The purpose of the present experiment was to study the effects of C.N.S. stimulants and depressant on the exocrine pancreas, and on the spontaneous motor activity in the rats. The results obtained are summarized as follows. 1. In animals treated with xanthine derivatives, the volume of pancreatobiliary secretion was markedly increased. 2. Total bilirubin output was elevated markedly in the xanthine derivatives and imipramine treated animals. The bilirubin concentration was increased in xanthine derivatives treated group. 3. The concentration of cholate in the bile was decreased in the chlorpromazine treated group. 4. The activity of lipase in the pancreatobiliary juice was elevated markedly in the xanthine derivatives treated group only. 5. In the all experimental groups, the activity of amylase in pancreatobiliary juice was significantly elevated. 6. In the caffeine treated group, spontaneous motor activity was markedly increased in $30{\sim}60$ minutes, and the amphetamine treated group showed the increased motor activity in first 30 minutes. 7. The group of rats treated with chlorpromazine showed markedly inhibited motor activity after 30 minutes, and the imipramine treated group showed similar result but less inhibition.

• Journal of computational fluids engineering
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• v.11 no.3 s.34
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• pp.1-7
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• 2006

Euler and Navier-Stokes flow analyses for helicopter rotor in hover were performed as low and high fidelity analysis models respectively for the future multidisciplinary design optimization(MDO). These design-oriented analyses possess several attributes such as variable complexity, sensitivity-computation capability and modularity which analysis models involved in MDO are recommended to provide with. To realize PC-based analyses for both fidelity models, reduction of flow domain was made by appling farfield boundary condition based on 3-dimensional point sink with simple momentum theory and also periodic boundary condition in the azimuthal direction. Correlations of thrust, torque and their sensitivities between low and high complexity models were tried to evaluate the applicability of these analysis models in MDO process. It was found that the low-fidelity Euler analysis model predicted inaccurate sensitivity derivatives at relatively high angle of attack.

• Transactions of the Korean Society of Automotive Engineers
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• v.6 no.1
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• pp.205-212
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• 1998

In this study, the effects of water vapor in inlet air on combustion efficiency, general performance, knock characteristics and emission gas concentration were investig- ated through the experiments of combustion and vibration analyses, emission gas analysis by changing water vapor quantity in inlet air with temperature and humidity auto control unit. With partial vapor pressure increase, the brake torque at wide open throttle status decreased and the average ignition delay angle increased, IMEP (indicated mean effective pressured using the integral and 3rd derivatives of filtered cylinder pressure as knock intensity, which matched well with the method of frequency power spectrum of block vibration signal. Water vapor in intake air had influence on the spark knock sensitivity. With the increase of water vapor content in intake air NOx emission was decreased and HC emission was increased.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• v.2
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• pp.45-50
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• 2006

본 연구는 Manta형 무인잠수정(Manta-type Unmanned Undersea Vehicle)의 동안정성을 검토한 후에 이 데이터를 기초로 하여 6자유도 수치 시뮬레이션을 실시하였다. 또한, 수치 시뮬레이션을 통하여 각각의 유체력미계수가 UUV의 6자유도 운동에서 미치는 영향에 대하여 검토하였다. 민감도 해석(Sensitivity Analysis)을 위한 방법은 간접법(Indirect Method)을 사용하였다. 수학모델 및 유체력미계수의 추정은 손경호 등(2006)의 결과를 이용하여 수행하였다. 연구를 통하여 UUV의 조종운동 모델에서 각각의 유체력미계수가 가지는 상대적 중요도를 알 수 있었다.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.25 no.6
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• pp.829-836
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• 2001

A dependable boundary reconstruction technique is proposed. The finite element method is used for the analysis of the direct heat conduction problem to realize the deformable grid system. An appropriate strategy for grid update is suggested. A complete sensitivity analysis is performed to obtain the derivatives required for restoration of the optimal boundary. With the result of the sensitivity analysis, the unknown boundary is sought using the sequential quadratic programming. The method is applied to reconstruction of boundaries with sinusoidal, step, and cavity form. The overall performance of the proposed method is examined by comparison between the estimated the exact boundaries.

• Proceedings of the KSME Conference
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• 2001.06a
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• pp.686-691
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• 2001

Structural optimization often require the evaluation of design sensitivities. The Semi Analytic method(SAM) is popular for shape optimization because this method has several advantages. But when relatively large rigid body motions are identified for individual elements, the SA method shows severe inaccuracy. In this paper, the improvement of design sensitivities corresponding to the rigid body mode is evaluated by exact differentiation of the rigid body modes. Moreover, the error of the SA method caused by numerical difference scheme is alleviated by using a series approximation for the sensitivity derivatives and considering the higher order terms.

• Computational Structural Engineering
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• v.7 no.2
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• pp.131-138
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• 1994

Derivatives of eigenvalues and eigenvectors for statistical properties is presented. Dynamic response of random system including uncertainties for the design variable is calculated with the first order perturbation method to original governing equation. In optimal design methods, there is fundamental requirement for design gradients. A method for calculating the sensitivity coefficients is developed using the governing equation and first order perturbed equation.