• Bulletin of the Korean Chemical Society
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• v.32 no.6
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• pp.1945-1950
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• 2011

The pyridinolysis of methyl phenyl phosphinic chloride is investigated kinetically in acetonitrile at -20.0 $^{\circ}C$. The Hammett and Br${\o}$nsted plots for substituent X variations in the nucleophiles are biphasic concave downwards with a break point at X = H, and unusual positive ${\rho}_X$ (= 2.94) and negative ${\beta}_X$ (= -0.48) values are obtained for the strongly basic nucleophiles. A stepwise mechanism with a rate-limiting step change from bond breaking for the weakly basic pyridines to bond formation for the strongly basic pyridines is proposed on the basis of biphasic concave downward Hammett and Br${\o}$nsted plots. Unusual positive ${\rho}_X$ and negative ${\beta}_X$ values are rationalized by the isokinetic relationship. The pyridinolyses and anilinolyses of four $R_1R_2$P(=O)Cl-type substrates, dimethyl, diethyl, methyl phenyl, and diphenyl phosphinic chlorides in acetonitrile are compared to obtain systematic information on phosphoryl transfer reaction mechanism. The combination of the two ligands, Me and Ph, shows unexpected kinetic results for both the anilinolysis and pyridinolysis: greatest magnitude of $k_H/k_D$ (= 2.10) involving deuterated anilines $[XC_6H_4NH_2(D_2)]$ for the anilinolysis, and exceptionally fast rate and biphasic concave downward free energy correlation for the pyridinolysis.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.22 no.4
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• pp.417-427
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• 1998

The effect of secondary flow on the heat transfer of a turbulent wake generated by a flat plate was experimentally investigated. The secondary flow was induced in a curved duct in which the flat plate wake generator was installed. All three components of turbulent heat flux were measured in the plane containing the mean radius of curvature of the curved duct. The results showed that mean temperature profiles deviate from the similarity of the straight wake because of the cold fluid transported from the free-stream. The half-width of the mean temperature profile increased rapidly by upwash motion of the secondary flow. The changes to turbulence structure caused by the secondary flow show more pronounced effect on heat transport than on momentum transport. This is because the response to the variation of flow conditions is delayed in temperature field. Negative production of the turbulent heat flux is observed in the inner wake region. From the conditional averaging, it has been found that the negative production of the turbulent heat flux is generated due to a mixing process between the hot and low momentum eddies occupied in the inner wake region and the cold and high momentum eddies in the potential region.

• Transactions of the Korean hydrogen and new energy society
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• v.24 no.2
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• pp.179-185
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• 2013

The behavior of surface film formation was greatly dependent on the speed of potential cycling. In $LiClO_4$ / EC + DEC, cyclic voltammetry results showed that the peaks originated from surface film formation on graphite electrode at the high charge-discharge rate was shifted to the lower potentials as the charge-discharge rate decrease. This indicates that surface films with different morphology and thickness were formed by different charge-discharge rate. Transmission electron microscopy (TEM) results indicated that the properties such as thickness and morphology of the surface film were greatly affected by the charge-discharge rate. Electrochemical impedance spectroscopy (EIS) showed that the resistance of surface film was affected by the speed of potential cycling. In addition, the charge transfer resistance was also dependent on the charge-discharge rate indicating that the charge transfer reaction was affected by the nature of surface film. TEM and EIS results suggested that the chemical property as well as the physical property of the surface film was affected by the charge-discharge rate.

• Journal of the Korea Safety Management & Science
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• v.17 no.3
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• pp.65-79
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• 2015

This study intended to investigate exploratorily the precedent factors affecting two types of perceived balances between work and life(family/leisure) and the antecedent ones affected by them, focusing on the metro train drivers. To attain this purpose, literature survey on the precedent factors, work-life balance, and antecedent factors was performed, and the study model was designed based on this survey, and then this model was analyzed empirically using Multiple-Regression. The results on the precedent factors showed that Job Demand, Self-Efficacy, and Age have significant effects on the negative transfer of work. On the other hand, it was shown that Affiliative Culture, Self-Efficacy, and Internal Locus of Control have significant effects on the family centered balance. And the results on the antecedent factors showed that family centered balance has significant effects on Job Satisfaction, Psychological Depression and Fatigue, Safety Behavior, and accident, and the negative transfer of work has significant effects on Physical and Psychological Depression and Fatigue, Emergency Stress, and Safety Behavior.

• Journal of English Language & Literature
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• v.55 no.6
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• pp.1057-1085
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• 2009

This paper addresses the question of why prepositions are particularly difficult forEFL learners. The first reason for such difficulty lies in the distinction between seemingly equivalent prepositions such as to and with, as in compared to and compared with. Most monolingual learners' dictionaries regard these two phrases as virtually synonymous. Yet, the results of the corpus analysis conducted in this study indicate that there are differences between the two. A second reason why EFL learners have problems with prepositions is that there are often variations in the inputdata. For example, although from generally follows different, in American English different than is also used. On the other hand, in British English, different to is the second most commonly used construction. This type of regional variation, confirmed in the corpus findings of the present paper, causes confusion in students of English. A learner who is not accustomed to British English may be puzzled by the expression different to. Finally, L1 negative transfer is responsible for the incorrect use of expressions such as discuss about. An error of this sort is the result of interference from the learner's mother tongue. The English verb discuss is not subcategorized for a preposition, whereas the equivalent Korean verb, for example, requires a noun phrase combined with the postposition.

• Journal of the Institute of Electronics and Information Engineers
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• v.51 no.1
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• pp.47-51
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• 2014

In this paper, unit cell and arrayed cover for improving the transfer efficiency of resonant wireless power transfer system is proposed. We used the characteristic of zero refractive index for focusing a magnetic field between the transmitting resonator and receiving resonator. For zero refractive index, we designed the unit cell structure that have a negative value of effective permeability. The size of proposed unit cell based on metamaterial structure is $70mm{\times}70mm{\times}3.2mm$, operating frequency is 13.56 MHz. And, the size of arrayed cover is $400mm{\times}400mm{\times}3.2mm$, is consists of 2-layers. The transfer efficiency of the proposed wireless power transfer system are 94.8 %, 93.2 %, 91.4 %, 90.8 % at 100 mm, 200 mm, 300 mm and 400 mm (distance between transmitting and receiving resonator), respectively. And proposed WPT system has a transfer efficiency high than 90 % over the overall distances.

• Journal of Korea Technology Innovation Society
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• v.20 no.3
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• pp.519-545
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• 2017

This study analyzed the factors influencing the technology transfer of Government-Funded Research Institutes from the perspective of resource-based view. In particular, we analyzed the effects of research resources, research capacity, and research results diffusion variables on technology transfer performance. The research resource variables affect the primary output of R&D (patents, research papers) but direct effect on the technology transfer performance was very weak. Among the research competency variables, patent-related variables such as patent registration, patent holdings have a significant effect on the technology transfer performance. However, the research papers have a negative effect on the technology transfer performance. The research results diffusion variables such as TLO organization and TLO budget may partly have a positive impact on technology transfer, but the statistical significance is not clear.

• Proceedings of the KSME Conference
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• 2004.04a
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• pp.1058-1063
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• 2004

This paper presents a new approach regarding thermal characteristics associated with a design of the high efficiency motor. Electrical conduction materials, such as coil and aluminum embedded in the core generate high heat exerting negative influence on both lifetime and performance of machine. Thus, it is necessary to design high efficiency motor considering heat transfer in order to improve motor performance and to be protected against overheating. In this paper, firstly, numerical analysis of electromagnetic field is carried out by the nonlinear transient finite element method (FEM). Secondly, the linear static FEA of magneto-thermal field is implemented by applying source current computed by the nonlinear transient analysis. FE results are validated in terms of electromagnetics and heat transfer by experiments. And then, the pseudo-transient topology optimization using a multi-objective function is performed. The proposed method is applied to a squirrel cage single-phase induction motor of the scroll compressor.

• Journal of Embryo Transfer
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• v.30 no.1
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• pp.33-43
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• 2015

Successful somatic cell nuclear transfer (SCNT) has been reported across a range of species using a range of recipient cells including enucleated metaphase II (MII) arrested oocytes, enucleated activated MII oocytes, and mitotic zygotes. However, the frequency of development to term varies significantly, not only between different cytoplast recipients but also within what is thought to be a homogenous population of cytoplasts. One of the major differences between cytoplasts is the activities of the cell cycle regulated protein kinases, maturation promoting factor (MPF) and mitogen activated protein kinase (MAPK). Dependent upon their activity, exposure of the donor nucleus to these kinases can have both positive and negative effects on subsequent development. Co-ordination of cell cycle stage of the donor nucleus with the activities of MPF and MAPK in the cytoplast is essential to avoid DNA damage and maintain correct ploidy. However, recent information suggests that these kinases may also effect reprogramming of the somatic nucleus and preimplantation embryo development by other mechanisms. This article will summarise the differences between cytoplast recipients, their effects on development and discuss the potential role/s of MPF and or MAPK in nuclear reprogramming.

• Korea Journal of Hospital Management
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• v.1 no.1
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• pp.37-55
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• 1996

This study attempts to analyze the factors affecting the intention of transferring to another hospitals among radiology technologists. 344 cases were reviewed in 5 university hospitals and 1 general hospital. Self-administered questionaire were given to study the socioeconomic characteristics, working conditions, job satisfaction level, and the reasons for transfer among the technologists. The major findings were as follows : 1. Job position and hospital characteristics had a statistically significant relationship with the intention of transferring to another hospital. 2. Those who were not satisfied with their salaries and promotional opportunity showed a higher tendency towards to transfer. 3. Those who were less satisfied with the opportunity for developing the personal ability and had the negative attitude on their job showed a higher tendency to transfer. 4. Those who did not sustain good relationship with their superiors and co-workers scored high on the tendency to transfer. 5. In the result of mutiple regression, recognition of radiation hazard, job satisfaction, satisfaction with salary levels, job attitude were significantly related to transfer. The above indicate that besides economic incentives, job satisfaction and organizational culture to promote their ability and form a good relationship with organization members were very important to decrease the intention of transfer. Since these results represent only 6 hospitals from a limited area, more hospitals nationwide, especially small and medium-sized institutions where there is a high turnover rate of employment, need to be examined in order to investigate the various factors that affect the intention of transferring.