• Korean Journal of Veterinary Research
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• v.32 no.2
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• pp.181-194
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• 1992

Two hundred and eighty nine strains of Yersinia enterocolitica isolated from healthy pigs were tested for the presence of 40~50 Megadalton virulence-associated plasmids and plasmidmediated in vitro virulence-associated properties, i.e., congo red uptake, calcium dependency, autoagglutination, CRMOX reaction, crystal violet binding and pyrazinamidase reaction. The correlationships between in vitro virulence-associated properties and the presence of 220 Kdalton outer membrane protein(OMP) were examined in strains with or without virulence-associated plasmids. The correlationships between the presence of plasmids on the production of the OMP and the expression of in vitro virulence-associated properties were studied with $CRMOX^+$ strains and acridine orangecured $CRMOX^-$ mutants. The results were as follows : 1. Of the in vitro virulence-associated tests with 289 strains of Y enterocolitica, 275 strains (95.2%) were positive for pyrazinamidase test, and followed by in order of crystal violet binding test, 226 (79.2% ) ; CRMOX test, 190 (65.7%) ; autoagglutination test, 1.85(64.0%) : calcium dependency test, 86 (29.8%) and congo red uptake test, 47(16.3%). 2. The correlationship between autoagglutination and CRMOX test(r=0.90) was highly significant (p<0.01). 3. In 190 strains(65.7%) bearing the virulence-associated plasmids(MW 40~50 Mdalton), the correlation between the presence of plasmids and their in vitro virulence-associated properties were highest with CRMOX test(r=0.93) and followed by in orders of AAG test(0.81), CV test(0.46), PYZ test(0.37) and CD test(0.18), but no correlationship between the presence of plasmids and CR test(-0.11). 4. The $CRMOX^+$ strains produced the 220 Kdalton OMP when they were cultured at $37^{\circ}C$, but not at $26^{\circ}C$. The presence of 220 Kdalton OMP was correlated significantly with in vitro virulence properties and the presence of virulence-associated plasmid, respectively. 5. In the isogenic $CRMOX^-$ mutant strains, of which plasmid were cured by treatment with acridine orange not only in vitro virulence-associated properties(CR 100%, CD 100%, AAG 82.6%, CV 58.3%) disappeared but also 220 Kdalton OMP(100%) was not produced. These results indicate that the positive CRMOX reaction is plasmid-mediated and the CRMOX test is potential as an in vitro virulence tests with Y enterocolitica.

• The Journal of the Acoustical Society of Korea
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• v.15 no.4
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• pp.24-31
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• 1996

In this paper, we present a speech translation system for hotel reservation, KT_STS(Korea Telecom Speech Translation System). KT-STS is a speech-to-speech translation system which translates a spoken utterance in Korean into one in Japanese. The system has been designed around the task of hotel reservation(dialogues between a Korean customer and a hotel reservation de나 in Japan). It consists of a Korean speech recognition system, a Korean-to-Japanese machine translation system and a korean speech synthesis system. The Korean speech recognition system is an HMM(Hidden Markov model)-based speaker-independent, continuous speech recognizer which can recognize about 300 word vocabularies. Bigram language model is used as a forward language model and dependency grammar is used for a backward language model. For machine translation, we use dependency grammar and direct transfer method. And Korean speech synthesizer uses the demiphones as a synthesis unit and the method of periodic waveform analysis and reallocation. KT-STS runs in nearly real time on the SPARC20 workstation with one TMS320C30 DSP board. We have achieved the word recognition rate of 94. 68% and the sentence recognition rate of 82.42% after the speech recognition tests. On Korean-to-Japanese translation tests, we achieved translation success rate of 100%. We had an international joint experiment in which our system was connected with another system developed by KDD in Japan using the leased line.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.3
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• pp.171-176
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• 2016

This paper proposes road safety facilities applying Hot-dip zinc-aluminum-magnesium alloy-coated steel sheets and coils to reduce the loss of function caused by the corrosion of steel in the service state. Vehicle crash simulations and full-scale crash tests were carried out to provide reliable information on evaluating the crash performance with the products of road safety facilities built with hot-dip zinc-aluminum-magnesium alloy-coated steel. From the results of the simulations and full-scale crash tests, the impact behaviors evaluated by the three-dimensional crash simulations considering the strain-rate dependency in a constitutive model were similar to those obtained from the full-scale crash test results. The full-scale crash test results met the crashworthiness evaluation criteria; hence, the proposed bridge barrier in this paper is ready for field applications.

• Tribology and Lubricants
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• v.23 no.6
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• pp.298-300
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• 2007

Frictional characteristics of mesoporous $SiO_2$ thin films were evaluated with different pore sizes. The films were manufactured by sol-gel and self-assembly methods to have a porous structure. The pores on the surface may play as the outlet of wear particle and the storage of lubricant so that the surface interactions could be improved. The pores were exposed on the surface by chemical mechanical polishing (CMP) or plasma-etching after forming the porous films. The ball-on-disk tests with mesoporous $SiO_2$ thin films on glass specimen were conducted at sliding speed of 15 rpm and a load of 0.26 N. The results show considerable dependency of friction on pore size of mesoporous $SiO_2$ thin films. The friction coefficient decreased as increasing the pore size. CMP process was very useful to expose the pores on the surface.

• Aerospace Engineering and Technology
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• v.2 no.2
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• pp.1-10
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• 2003

An airship is statically unstable, because it has no wing, comparatively small tail and large hull. Hence, an accurate prediction of dynamic stability is critical. In this study, dynamic stability data of the Mid-Size Airship is acquired through forced oscillation wind tests. The test was done in BAR LAMP which is Birhle Applied Research Inc's facility located in Germany. The test was composed with 16 static runs and 26 dynamic runs. As a result, dynamic characteristics of the airship depends on sideslip angle, angular rate and its direction as well as angle of attack. Generally, it is obtained that 3 directional moments have damping, but normal force, side force, and cross-derivatives are unstable. The dynamic derivatives are not sensitive to control surfaces, but have nonlinear dependency on sideslip angle.

• Transactions of Materials Processing
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• v.27 no.4
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• pp.227-235
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• 2018

The flow stresses have been identified prior to a numerical simulation for predicting a deformation of materials using the experimental or analytical analysis. Recently, the flow stress models considering the temperature effect have been developed to reduce the number of experiments. Artificial neural network can provide a simple procedure for solving a problem from the analytical models. The objective of this paper is the prediction of flow stress on the fiber metal laminate using the artificial neural network. First, the training data were obtained by conducting the uniaxial tensile tests at the various temperature conditions. After, the artificial neural network has been trained by Levenberg-Marquardt method. The numerical results of the trained model were compared with the analytical models predicted at the previous study. It is noted that the artificial neural network can predict flow stress effectively as compared with the previously-proposed analytical models.

• Transactions of Materials Processing
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• v.14 no.7 s.79
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• pp.607-612
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• 2005

In this paper, warm deep drawing process with local heating and cooling technique was attempted to improve the formability of AZ31 magnesium alloy which is impossibly to form by conventional methods at room temperature by finite element method and experiment. For FE analysis, in first model with considering heat transfer, both die and blankholder were heated to 573K while the punch was kept at room temperature by cooling water. Also distribution of thickness and von Mises stress at room temperature and 498k for warm deep drawing were compared by FEM. Uniaxial tension tests at elevated temperature were done in order to obtain the temperature dependence of material constant under temperature of $293K\~573K$ and cross head velocity of $5\~500mm/min$. The phenomenological model for warm deep drawing process in this work was based on the hardening law and power law strain rate dependency. Deep drawing experiment were conducted at temperatures of room temperature, 373K, 423K, 473K, 498K, 523K, and 573K for the blank and deep drawing tools(holder and die) and at a punch speed of 10mm/min.

• Korean Journal of Food Science and Technology
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• v.19 no.6
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• pp.515-519
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• 1987

The kinetics of thermal softening of chinese cabbage was investigated by puncture tests with an Instron. It was concluded that low temperature-long time blanching and pasteurization process provided an opportunity of improving the texture of pasteurized Kimchi. The rate of softening showed apparent first order kinetics, and the apparent Arrhenius activation energies ranged from 2.8-42.4 kcal/mol. The temperature dependency of the softening rate during pasteurization was more profound by blanching at blanching at higher temperature.

• Geotechnical Engineering
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• v.2 no.1
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• pp.55-66
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• 1986

Considering the effects of confining pressure, initial shear stress, cyclic stress ratio and number of loading cycles, cyclic triaxial tests are carried out to clarify the soil dynamic properties such as shear modulus and value of material damping of clay under undrained cyclic loading conditions. The results show that no obvious dependency on initial shear stress and effective confining stress are recognized in the shear modulus and damping ratio plotted versus strain. However, the shear modulus decreases and the damping ratio increases with increasing axial strain. When compared with others, it is also revealed that the shear moduli are distributed within the range curves obtained using empirical equations derived by Marcuson et al. (3) and Kokusho et al. (4), and damping ratios are distributed between the curves obtained by Kokusho et al. (4) and Ishihara et al. (9).

• KDI Journal of Economic Policy
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• v.26 no.1
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• pp.105-140
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• 2004

Korea is entering the class of aging population nations. This paper investigates the extent demographic factors and the aging population affect the saving rate, using an extended life-cycle/permanent-income hypothesis on saving. The results of the tests with Korean household survey data from 1977 to 2002 reveal that real saving rates increase when the duration of lifetime and per household real disposable income rise, and decrease when the growth rate of income and net worth-to-GDP ratio rises. The growth rate of per household real disposable income has negative effects, suggesting that households calculate their life cycle income in a forward looking manner. The elasticities with respect to a change in the lifetime horizon and the growth rate of per household income are 0.58 and -0.03, respectively. A one percent rise in the net worth to GDP ratio reduces the saving rate by 0.3 percent. A one percent rise in per household income increases it by 0.33 percent. The younger-age and the elder-age dependency ratios have insignificant effects on the household saving rate behavior. When Korean life expectancy rises, the private saving rate declines modestly and the government saving rate declines substantially. The economy's real net saving rate declines from 33 percent in 2002 to 30 percent by the year 2030.