• Journal of the Chungcheong Mathematical Society
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• v.31 no.4
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• pp.421-427
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• 2018

The aim of this study is to investigate the prolongations of G-structures immersed in the generalized almost r-contact structure on a manifold M to its tangent bundle T(M) of order 2. Moreover, theorems on Hsu structure, integrability and (${F\limits^{\circ}},\;{{\xi}\limits^{\circ}}{{\omega}\limits^{\circ}}_p,\;a,\;{\epsilon}$)-structure have been established.

• 한국전산유체공학회:학술대회논문집
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• 1999.05a
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• pp.23-28
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• 1999

A mutigrid convergence acceleration technique is presented for computing hypersonic inviscid and viscous flows in equilibrium state. The governing equations are solved using an explicit Runge-Kutta method. Curve fitting data in NASA Reference Publication 1181, 1260 are used to calculate equilibrium properties. In order to ensure stability, damped prolongation and modified implicit residual smoothing are proposed. Blunt body test cases are presented to demonstrate the robustness and the efficiency in performance of the proposed methods

• Proceedings of the Korean Biophysical Society Conference
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• 1999.06a
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• pp.64-64
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• 1999

Amitriptyline has been known to induce QT prolongation and ventricular arrhythmias such as torsades de pointes which causes sudden death. We studied the effects of amitriptyline on the human ether-a-go-go-related gene (HERG) channel expressed in Xenopus oocytes.(omitted)

• YAKHAK HOEJI
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• v.29 no.5
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• pp.253-259
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• 1985

In order to search a more active and safer compound, piperine derivatives with substituents in piperidine residue were synthesized and evaluated on CNS depressant activity. N-Piperoyl-2-methylpiperidine (I) and N-piperoyl-3-methylpiperidine (II) were potent in strychnine-induced convulsion. Compound I and N-piperoyl-3-hydroxypiperidine (IX) exhibited a potent inhibitory effect againt pentetrazoleinduced convulsion and a significant prolongation effect of hexobarbital-induced sleeping time. The hydroxy derivatives were more toxic than the methyl derivatives.

• Toxicological Research
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• v.22 no.2
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• pp.109-116
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• 2006

Safety pharmacology studies are conducted to investigated the potential undesirable pharmacodynamic effects of a substance on physiological functions in relation to exposure in the therapeutic range and above. In the International Conference on Harmonisation (ICH), the guideline 'S7A: Safety Pharmacology Studies for Human Pharmaceuticals' has been developed and reached Step 5 of the ICH process in 2001. Now the Korea Food and Drug Administration (KFDA) are going to transfer 'The Guideline for General Pharmacology' into 'The Guideline for Safety Pharmacology'. Safety pharmacology studies should be performed in compliance with Good Laboratory Practice (GLP). Thus, the present paper reviews the Japanese GLP guidelines for pharmaceuticals to help the conduct and inspection of safety pharmacology studies in compliance with GLP. We also reviewed the ICH guidelines 'S7B revised : The Nonclinical Evaluation of the Potential for Delayed Ventricular Repolarization (QT Interval Prolongation) by Human Pharmaceuticals' and 'E14 : The Clinical Evaluation of QT/QTc Interval Prolongation and Proarrhythmic Potential for Non-antiarrhythmic Drugs' to apply our drug approval systems.

• The Korean Journal of Pharmacology
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• v.19 no.1
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• pp.61-69
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• 1983

Hypothermia is an essential preparatory procedure for cardiac surgery, which lows the metabolic rate and myocardial oxygen demand. However, hypothermia itself is a stress enough to change the tonus of sympathoadrenal system, especially the cardiovascular responses to the catecholamines. It is reported that the positive chronotropic and inotropic response of catecholamines is exaggerated during hypothermia because of decreased norepinephrine uptake at the junctional cleft or decreased catecholamine metabolism. On the other hand, there are evidences of diminished catecholamines responses in low temperature ana further, interconversion of adrenergic receptors is also suggested. Present investigation was planned to observe the cardiovascular changes and its responses to catecholamines during surface hypothermia in cat. Healthy mongrel cats, weighing $2{\sim}3\;kg$, anesthetized with secobarbital(30 mg/kg), were permitted to hypothermia by external cooling technic. Esophageal temperature, ECG (lead II), heart rate, left ventricular pressure with dP/dt, carotid artery pressure and left ventricular contractile force were monitored with Polygragh (Model 7, Grass), and the respiration was maintained with artificial respirator (V 5 KG, Narco). Followings are summarized results. 1) Surface cooling caused progressive decrease of body temperature and reached $l8.8{\pm}0.8^{\circ}C$ and $16.9{\pm}0.6^{\circ}C$ in 120 and 150 min respectively, after immersion into ice water, and ventricular fibrillation was developed at $20.4{\pm}0.65^{\circ}C$. 2) Heart rate, blood pressure and myocardial contractility were decreased after initial increase as the body temperature falls. 3) Systolic and diastolicdd P/dt of left ventricular pressure were decreased and that the decrement of diastolic dP/dt was more marked. 4) On ECG, ST depression, Twave inversion and prolongation of PR interval were prominent in hypothermia, and moreover, the prolongation of PR interval was marked just prior to the development of ventricular fibrillation. 5) The cardiovascular responses to catecholamines, especially to isoproterenol, were suppressed under hypothermia.

• Asian Journal of Turfgrass Science
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• v.18 no.2
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• pp.71-76
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• 2004

Solid typed organic fertilizer from cattle manure may Increase plant root growth with the residual effect on soil fertility if it was applied directly into root system. It may also increase labour efficiency by simplifying the work process of manure application to soil. This research was carried out from May to October 1999 to study the fertility prolongation effects of bar typed organic fertilizer from poultry manure by analysing plant growth model compare with those of the chemical fertilizer or powder typed manure. The results showed that the bar typed organic fertilizer increased growth rates of shoot and root system with extending the effect of its fertility by slow releasing on pepper plant. Especially, solidifying organic manure into the bar type made possible the application of cattle manure under plastic mulching. And it also has benefits on simplifying the application process of the fertilization and effect on an extending soil fertility.

• The Journal of the Acoustical Society of Korea
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• v.14 no.5
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• pp.74-82
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• 1995

This paper is study on the voice dialing using HMM and post processing of the connected digits. HMM algorithm is widely used in the speech recognition with a good result. But, the maximum likelihood estimation of HMM(Hidden Markov Model) training in the speech recognition does not lead to values which maximize recognition rate. To solve the problem, we applied the post processing to segmental K-means procedure are in the recognition experiment. Korea connected digits are influenced by the prolongation more than English connected digits. To decrease the segmentation error in the level building algorithm some word models which can be produced by the prolongation are added. Some rules for the added models are applied to the recognition result and it is updated. The recognition system was implemented with DSP board having a TMS320C30 processor and IBM PC. The reference patterns were made by 3 male speakers in the noisy laboratory. The recognition experiment was performed for 21 sort of telephone number, 252 data. The recognition rate was $6\%$ in the speaker dependent, and $80.5\%$ in the speaker independent recognition test.

• Clinical and Experimental Pediatrics
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• v.58 no.7
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• pp.263-266
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• 2015

Purpose: Ventricular repolarization is assessed using the QT interval corrected by the heart rate (QTc) via an electrocardiogram (ECG). Prolonged QTc is associated with an increased risk of arrhythmias and cardiac mortality. As there have been few reports regarding the effects of hyperthyroidism on ventricular repolarization, we studied the association between serum free thyroxine (free T4 [fT4]) and thyroid stimulating hormone (TSH) levels and the QTc interval. Methods: Thirty-eight patients with hyperthyroidism (<30 years old) were included, and we used their clinical records and available ECGs (between August 2003 and August 2011) to evaluate the association between their fT4 and TSH levels and their QTc interval. In addition, we studied the ECGs of 72 age-matched patients with no hyperthyroidism (control group) and compared their data with that from the patients group. Results: The QTc duration in patients with hyperthyroidism was significantly prolonged compared to that in the control subjects (P<0.001). In addition, the number of hyperthyroid patients with abnormal prolonged QTc was significantly higher than that in the control group (P<0.001). Among the patients with hyperthyroidism, patients with prolonged QTc and borderline QTc had higher fT4 levels and there was positive correlation between their fT4 levels and their QTc interval (P<0.05). However, no correlation was observed between their TSH levels and their QTc interval. Conclusion: We report that hyperthyroidism is associated with QTc prolongation. The correlation between the fT4 levels and the QTc interval suggests that thyroid status is associated with QTc values and the risk of cardiac mortality.

• Korean Journal of Food Science and Technology
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• v.27 no.4
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• pp.546-554
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• 1995

Vacuum cooling of crisphead lettuce by pilot-scale vacuum cooling apparatus, transportation under the conventional and cold-chain systems and distribution were carried out for its freshness prolongation and application of cold-chain system for fresh fruits and vegetables. Changes in temperatures of crisphead lettuce were also measured during transportation. $Q_{10}$ value for respiration rate of crisphead lettuce was $1.7{\sim}2.4$ and its initial freezing point was $-0.2^{\circ}C$. Cooling the vegetable to $0^{\circ}C$ was possible in less than 30 minutes by vacuum cooling. The shelf-life was extended by more than 90% by the combination of vacuum cooling and low temperature distribution.