• Transactions of the Korean Society of Automotive Engineers
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• v.5 no.5
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• pp.86-96
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• 1997

In this paper, engine-CVT consolidated control algorithm was developed. Engine -CVT control strategy suggested uses throttle control based on power difference and CVT ratio control based in CVT ratio map. Simulation results showed that the larger the rate of CVT ratio, the better the engine performance in the optimal operation line. Also, it was found that the engine performance where the magnitude of the acceleration changes abruptly depends on the magnitude of the rate of CVT ratio. Comparing the results of CVT control only without engine control, the engine-CVT control algorithm suggested in this work showed better performance demonstrating that the consolidated control algorithm should be required for the engine optimal operation.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1993.10a
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• pp.518-523
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• 1993

A computer program has been developed for analyzing the two-dimensional unsteady conservation equations for transport phenomena in the ool region of direct rolling with semi-solid metal in order to describe the velocity and temperature, and the solidification process of the semi-solid metal. The energy equations of cooling roll is solved simultaneously with semi-solid metal in order consider heat transfer through the cooling roll. The FDM(finite difference method) and FEM(finite element method) are used in region of pool and roll, respsctively, to reduce computing time and to improve accuracy of calculation. In the present study, influence of solid fraction and casting speed are investigated in a point of view of strip formability with semi-solid metal.

• Transactions of the Korean Society of Automotive Engineers
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• v.5 no.6
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• pp.111-119
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• 1997

In this paper, engine-CVT consolidated control performance were investigated experimentally. Engine-CVT consolidated control was composed of engine throttle control based on power difference and CVT ratio control based on CVT ratio map. Experimental results showed that engine optimal operation was obtained while satisfying the driver's desire, i. e., following the given drive mode by engine-CVT consolidated control. Also, it was found that engine performance is subjected to inertia of the powertrain where the magnitude of acceleration changes abruptyly. Comparing with the results of CVT only control, the results of engine-CVT consolidated control showed better performance. Therefore, in order to meet the driver's desire as well as keeping the engine optimal operation, the engine-CVT consolidated control could be suggested as an integral solution.

• Proceedings of the SOHE Conference
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• 1997.12a
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• pp.39-43
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• 1997

Toha-jeod was manufactured by seven methods ; low salt group (L:15% sodium chloride), high salt g group (H:23% sodium chloride), 50% conventional soybean sauce group (S), low salt group containing 2% w wheat bran (W2%-L), high saIt group containing 2% wheat bran (W2%-H),high salt group containing 2% wheat bran (W2%-H), high salt group containing 4% wheat bran (W4%-H). After these seven groups were refrigerated at $4{\pm}1^{\circ}C$, they were sampled at intervals of three months and analyzed functional components. The free amino acid in Toha-jeod which are omitine, glutamic acid, leucine, alanine, lysine and valine increased gradually up to six months of fermentation and decreased by nine months. Conventional soybean sauce group increased continuously during the fermentation process. Hypoxanthine was altered almost among other nueletides. ATP was not detected, IMP and inosine had disapapted after the six months fermentation. Polyene fatty acids and n-3 fatty acids were decreased and s saturated fatty acids were not altered in the group containing wheat bran during fermentation. In the Hunter values, the group containing wheat bran and high salt group showed lower level than the group n not containing wheat bran and low salt group. Redness indicating the value of Toha-jeod increased as Toha-jeod was fermentated. Low salt group and conventional soybean sauce group were superior to other groups in the extent of redness. As the fermentation of Toha-jeod progressed for a long time, molecular weight distribution tended to become less molecular and the formation of chitin oligosaccharides was increased significantly. After nine months of fermentation, 24.75% chitin oligosaccharides [($GlcNAd_4$ ~ ($GlcNAd_8$, M.W. 823~1789] were created in the high salt group containing 2% wheat bran. [($GlcNAd_6$. M.W. 1236J , that is NACOS-6, which was reported as an antitumor activity material, was present in 4.01~4.37% of total Toha chitin content. 66.30% chitin oligosaccharides were created in conventional soybean sauce.

• Transactions of the Korean Society of Automotive Engineers
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• v.25 no.3
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• pp.367-373
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• 2017

In this paper, a new shift map was proposed to improve the fuel economy of a transmission mounted electric device(TMED) type dual clutch transmission(DCT) plug-in hybrid electric vehicle(PHEV) by considering transmission and motor losses. To construct the shift map, powertrain efficiencies of the engine-DCT-motor were obtained at each gear step. A shift map that provides the highest powertrain efficiency was constructed for the given wheel torque and vehicle speed. Simulation results showed that the fuel economy of the target PHEV can be improved by the new shift map compared with the existing engine optimal operating line(OOL) shift control.

• Proceedings of the KSME Conference
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• 2000.04a
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• pp.690-695
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• 2000

This article deals with the analytic results on the development and application of the Spherical CVT. The Spherical CVT is marked by its simple configuration, the infinite torque multiplication characteristic, and the smooth transitions between forward/neutral/reverse states of output speed. In this study, we describe the conceptual principles behind the Spherical CVT and some applications of it, which we developed recently. And, we propose the shifting algorithm based on the analytic consideration of CVT powertrain system. Contrary to conventional shifting algorithms using the OOL(optimal operating line) of the power source, the proposed shifting algorithm is represented as a $2^{nd}$ order equation in an explicit form, and it reveals the possibility of theoretic design of all optimal controller. As an example, we present numerical results that demonstrate the energy saving possible and the proposed shifting algorithm from the use of the Spherical CVT over standard reduction gear unit, using an ideal dc motor model.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.11 no.9
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• pp.4264-4279
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• 2017

In this paper, maximum likelihood-based automatic lexicon generation using mixed-syllables is proposed for unlimited vocabulary voice interface for East Asian languages (e.g. Korean, Chinese and Japanese) in AI-assistant based interaction with mobile devices. The conventional lexicon has two inevitable problems: 1) a tedious repetition of out-of-lexicon unit additions to the lexicon, and 2) the propagation of errors during a morpheme analysis and space segmentation. The proposed method provides an automatic framework to solve the above problems. The proposed method produces a level of overall accuracy similar to one of previous methods in the presence of one out-of-lexicon word in a sentence, but the proposed method provides superior results with the absolute improvements of 1.62%, 5.58%, and 10.09% in terms of word accuracy when the number of out-of-lexicon words in a sentence was two, three and four, respectively.

• Journal of Embryo Transfer
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• v.11 no.2
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• pp.95-101
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• 1996

The present study investigated the effect of treatment with nocodazole on the efficiency of cell cycle synchronization and development of mouse 4-cefl embryos. In addition, developmental ability of reconstituted embryos that received nuclei from 4-cell embryos synchronized with nocodazole at M phase was examined in vitro and in vivo. (1) When 4-cell blastorneres exposed to culture medium containing l$\mu$g /ml nocodazole for 2, 4, 6 and 8 hrs, 40% (40/10l), 75% (l19/159), 85% (87/102) and 97% (155/160) of nuclei were synchronized at M phase, respectively. (2) Treated with nocodazole for 4 hrs, the proportion of 4-cell embryos developed to blastocysts (98%, 60/61) was not significanUy different from that of the control embryos (98%, 196/201). However, the developmental ability of 4-cell embryos treated for 8 (87%, P<0.05)and 12 hrs (76%, P

• Microbiology and Biotechnology Letters
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• v.28 no.2
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• pp.105-110
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• 2000

Various environmental factors such as pH, temperature and initial glucose concentration were investigated for enhancing cell growth in fermentations of Phellinus linteus WI-OOl, a producer of polysaccarides with potent anticancer activities. Optimal pH and temperature were around 5.5 and $28^{\circ}C$, respectively. Relatively little variation of pH was observed ranging between 5.5 and 6.5 during the whole fermentation period. Maximum cell concentration and specific growth rate were investigated in the media containing initial glucose concentrations of 0.5%, 1 %, 2%, 3% and 4%. High initial glucose concentration enhanced biomass production but showed negative effect on specific growth rate. In bioreactor experiments with various feeding strategies, increases of 28% and 42% in final cell concentration were obtaind as compared to conventional batch process, by adopting pulse and continuous supplement of 2% glucose solution, respectively.

• Journal of Korean Academy of Nursing Administration
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• v.5 no.1
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• pp.99-111
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• 1999

The purpose of this study was to investigate the relationship between public health nurse's decentralization, participation of decision-making and organizational commitment and to provide basic data for the improvement of public health nurse's organizational effectiveness. Data were collected from Aug. 1 to Aug. 30, 1998 (collection rate-96%) through questionnaires by 163 public health nurses working in Taejon and Chungnam. The instruments were used Van de Ven and Ferry's Job Authority scale, Hage and Aiken's Hierarchy of Authority scale. Participation of Decision-making scale. and Mowday's Organizational Commitment Questionnaires. Collected data were analyzed by SPSS PC+. The results were as follows 1. There were significant differences of age(P<.05), career, spending time for major study, and experience who called expert(P<.01) to decentralization. 2. There were significant differences of career (P<.05), educational level, and spending time for major study(P<'OOl) to participation of decision-making. 3. There were significant differences of career. spending time for D1ajor study, self-evaluation to specialty(P<.01) and experience who called expert (P<.001) to organizational commitment. 4. 1) A significant correlation was found between decentralization and self-evaluation to specialty (P<.05), age, career, spending time for major study, and experience who called expert (P<.01.). 2) A significant correlation was found between participation of decision-making and self-eval-uation to specialty(P<.05), age, career, spending time for major study, experience to call expert, and decentralization (P<.01). 3) A significant correlation was found between organizational commitment and age(P<.05). career. spending time for major study, self-eval-uation to specialty, experience who called expert. decentralization, and participation of decision-making (P<.01). 5. Decentralization w·as the best predictor of or ganizational commitment(17%), also experience who called expert, self-evaluation to specialty explained the organizational commitment.