• 한국자원식물학회지
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• 제7권1호
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• pp.1-5
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• 1994

To decrease the bolting rate of Angelica gigas, The growth inhibitors such as MH, Pp333 (paclobutrazol) and CCC(chloroniequat or Cycocel) were treated twice with the interval of 20 days atthe forming stage of flower bud.Growth and bolting rate in plot treated inhibitors were retarded and decreased, and the yield ofroots was also decreased compared with non - treatment. The treatments of MH and Pp333 amongthree inhibitors showed the better effects in decreasing the bolting than that of CCC, but they did notshow the significant in the yield and contents of decursin among each of them.In order to improve the decreasing effects by chemicals, selection of suitable reagents, concentrationand number of treatment should be investigated.

• 오토저널
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• 제5권4호
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• pp.41-46
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• 1983

The influence of inlet air humidity on the flame velocity and combustion of the spark ignition engine were described experimentally by means of the flame velocity measuring apparatus using ion-current. The flame velocity are greatly influenced air fuel ratio and engine speed, and linealy decrease according to the increasing of inlet air humidity. The flame travell curve is very similar to the rate of mass burned and combustion progressive is estimated mostly by only the rate of mass burned curve. The decreasing of the mean flame velocity is about 0.4m/s for increasing of 0.001 specific humidity and we think the reason is mainly decreasing of thermal conductivity.

• Bulletin of the Korean Chemical Society
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• 제10권5호
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• pp.448-452
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• 1989

NADH analogs, 1-benzyl-3-substituted (X)-1,4-dihydropyridines 1-4 (1: X = $CONH_2$; 2: X = $CSNH_2$; 3: X = $COOCH_3$; 4: X = $COCH_3$) were synthesized. The second order rate constants for hydration reaction and oxidation reactions by $Cu^{2+}$, $Fe(CN)_6^{3-}$ or methylacridinium iodide (MAI) of the compounds were determined. For all reactions investigated, the rate constants increased with decreasing electronegative character of the 3-substituents of 1,4-dihydropyridines : the decreasing order of the reaction rates was 2>1>3>4. However, the sensitivity of the reaction rates on the 3-substituents differed among the reactions. This was explained in view of mechanisms of the reactions.

• 한국광학회지
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• 제12권5호
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• pp.347-351
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• 2001

Zeeman 감속기를 사용하여 감속한 나트륨 원자를 자기광학적 방법으로 포획하였다. 자기광학적 방법으로 포획된 원자의 개수와 온도를 측정하고, 포획이 가능한 포획광의 주파수 영역과 펌핑광의 주파수영역을 나타내었다. Zeeman 감속기로부터 유입하는 원자의 양을 조절한 경우에 원자 개수의 증가율과 감소율을 측정하고, 이들 차이로부터 $N_2$에 비례하는 손실에 대하여 논의하였다.

• ETRI Journal
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• 제45권1호
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• pp.119-130
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• 2023

We propose a quantized gradient search algorithm that can achieve global optimization by monotonically reducing the quantization step with respect to time when quantization is composed of integer or fixed-point fractional values applied to an optimization algorithm. According to the white noise hypothesis states, a quantization step is sufficiently small and the quantization is well defined, the round-off error caused by quantization can be regarded as a random variable with identically independent distribution. Thus, we rewrite the searching equation based on a gradient descent as a stochastic differential equation and obtain the monotonically decreasing rate of the quantization step, enabling the global optimization by stochastic analysis for deriving an objective function. Consequently, when the search equation is quantized by a monotonically decreasing quantization step, which suitably reduces the round-off error, we can derive the searching algorithm evolving from an optimization algorithm. Numerical simulations indicate that due to the property of quantization-based global optimization, the proposed algorithm shows better optimization performance on a search space to each iteration than the conventional algorithm with a higher success rate and fewer iterations.

• The Korean Journal of Physiology and Pharmacology
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• 제2권3호
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• pp.287-295
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• 1998

Diazepam is known to have cardiovascular depressive effects through a combined action on benzodiazepinergic receptor and the GABA receptor-chloride ion channel complex. Moreover, it is known that barbiturates also have some cardiovascular regulatory effects mediated by the central GABAergic system. Therefore, this study was undertaken to delineate the regulatory actions and interactions of these systems by measuring the responses of the cardiovascular system and renal nerve activity to muscimol, diazepam and pentobarbital, administered intracerebroventricularly in rabbits. When muscimol $(0.03{\sim}0.3\;{\mu}\;g/kg)$, diazepam $(10{\sim}100\;{\mu}\;g/kg)$ and pentobarbital $(1{\sim}10\;{\mu}\;g/kg)$ were injected into the lateral ventricle of the rabbit brain, there were similar dose-dependent decreases in blood pressure (BP) and renal nerve activity (RNA). The relative potency of the three drugs in decreasing BP and RNA was muscimol ＞ pentobarbital ＞ diazepam. Muscimol and pentobarbital also decreased the heart rate in a dose-dependent manner; however, diazepam produced a trivial, dose-independent decrease in heart rate. Diazepam $(30\;{\mu}g/kg)$ augmented the effect of muscimol $(0.1\;{\mu}g/kg)$ in decreasing blood pressure and renal nerve activity, but pentobarbital $(3\;{\mu}g/kg)$ did not. Bicuculline $(0.5\;{\mu}g/kg)$, a GABAergic receptor blocker, significantly attenuated the effect of muscimol in decreasing BP and RNA, either alone or with diazepam, and that of pentobarbital in decreasing BP and RNA, either alone or with muscimol. We inferred that the central benzodiazepinergic and barbiturate systems help regulate peripheral cardiovascular function by modulating the GABAergic system, which adjusts the output of the vasomotor center and hence controls peripheral sympathetic tone. Benzodiazepines more readily modulate the GABAergic system than barbiturates.

• 품질경영학회지
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• 제10권2호
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• pp.2-9
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• 1982

In principle the methods of increasing the reliability of complex system can be classified into the following four basic methods: (1) using the stand-by redundancy; (2) decreasing the failure rate of the system; (3) decreasing the time of continuous operation; (4) decreasing the mean repair time. Among the above four methods, it is generally known that the method of stand-by redundancy is the most effective general, to increase the reliability of systems. Therefor this paper aims to compare the gain in reliability which is achieved by applying stand-by redundancy with other methods, and to show the characteristics of each method From the comparison of the methods of increasing reliability, the following important facts are found: When the method of stand-by redundancy is used to increase the reliability of complex systems intended for long-term operation, a hight multiplicity of stand-by redundancy is required. Thus an increase of the reliability of complex system by applying stand-by redandancy is realized at the expense of characteristics such as weight, size, cost, increased complexity of operation conditions. And this property restricts its use in systems which are critical with respect to weight, size, cost or operation conditions. The method of stand-by redundancy is the most effective when this method is used to increase the reliability of complex systems intended for short-term operation, and the method of decreasing failure rate is the most effective when it is used to increase the reliability of systems intended for long-term use. The methods of increasing reliability discussed in this paper make it possible to make highly reliable systems. But it is not possible to make a highly reliable system using a single method of increasing reliability, even if it is the most effective one. Therefore it is recommended to use all or a majority of the above four methods by choosing it in accordance with the properties of the system under construction.

• 수산해양기술연구
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• 제35권1호
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• pp.35-40
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• 1999

We selected horse mackerel Trachurus japonicus, mackerel Scomber japonicus and arrow squid Todarodes pacificus, to use in the experiment. These fishes migrate to the Cheju coast and were caught by set-net. We studied the leading effect on the fish schools using the attracting lamps in an outdoor water tank at the Marine Research Institute in Cheju National University. The results obtained are summarized as follows; 1. The attracting rate of fish schools was increasing as the time between switching on and off each lamp was getting longer when each of the attracting lamps was switched on and off in order. However, the attracting rate of mackerel school showed a tendency to be higher than that of the other two species. 2. The attracting rate of fish schools was increasing as the time of switching off the lamps was getting longer when the attracting lamps which had been switched on were switched off in order. However, the attracting rate of mackerel school showed a tendency to be higher than that of the other two species. 3. The attracting rate of fish schools was decreasing as the speed of moving the attracting lamp was getting faster when the attracting lamp was moving. However, the attracting rate of mackerel school showed a tendency be higher than that of the other two species. 4. To determine the distance between the attracting lamps, there would be two methods. One is switching on and off the attracting lamps in order, and the other is switching off the attracting lamps in order which had been switched on. The methods showed that the attracting rate of fish schools were decreasing as the distance between the attracting lamps were getting longer. However, the attracting rate of mackerel school showed a tendency to be higher than that of the other two species.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2008년도 춘계 학술발표회 초청강연 및 논문집
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• pp.97-104
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• 2008

The objective of this study was to investigate the strength characteristics of frozen clay. Compressive strength tests were performed on frozen clay with different water contents at various temperatures. The dry density of specimens and strain rate was kept constant. Test results showed that compressive strength increased with increasing water content and decreasing temperature. The increase in peak strength became more significant the lower the temperature for a given water content. The failure mode changed from brittle to ductile deformation with increasing water content and decreasing temperature. Tests also showed an increase in deformation modulus with increasing peak strength, increasing water content and decreasing temperature.

• 연구논문집
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• 통권26호
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• pp.95-102
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• 1996

The carbide growth behavior of MAR-M247 LC alloy was investigated by directional solidification and quench method. The carbide volume fraction, trapping and growth behavior were correlated with the growth rate. It was found that the carbide volume fraction decreases at slower growth rate. This decreasing was caused by lower solid-liquid interface trapping ability at the slower growth rate.