• Transactions of the Korean Society of Mechanical Engineers B
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• v.26 no.12
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• pp.1756-1762
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• 2002

To effectively meet current regulations on the exhaust emissions of diesel engine required to control the deterioration of air pollution in the whole world, this study is to investigate the effects of water induction through the air intake system on the characteristics of combustion and exhaust emissions in IDI diesel engine. A method fur supplying water through the air intake system to reduce the exhaust emissions has been considered with other methods such as water introduction in the form of water-in-fuel emulsion or water injection directly into the combustion chamber, but it has not been studied about the effects of water on the combustion concepts and the characteristics of exhaust emissions in detail until now. In this study, the formation of NOx was significantly suppressed by decreasing the gas peak temperature during the initial combustion process because the water play a role as a heat sink during evaporating in the combustion chamber, but the smoke was slightly increased by increasing water amount.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.43 no.1
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• pp.28-31
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• 1998

Nodule development was regulated partially by host plant factors originating in the shoots and roots. This study was performed to identify the origin of the factors regulating nodulation in supernodulating soybean (Glycine max [L.] Merr.) mutant 'SS2-2' which was isolated recently from ethyl methanesulfonate (EMS) mutagenesis of 'Sinpaldalkong 2'. Self- and reciprocal-grafts were made among three soybean genotypes which consisted of two supernodulating mutants, SS2-2 and 'nts 382', and a normal nodulating Sinpaldalkong 2. Self-grafted supernodulating mutants were characterized by greater nodule number, nodule dry weight, and $C_2$H$_2$ reduction activity than self-grafted wild types. They were also characterized by relatively higher nodule to root dry weight. Significant shoot genotypic effects were observed on nodule number, nodule dry weight, and $C_2\;H_2$ reduction activity per plant, whereas varying root genotypes had no effects. From this result, it is surmised that supernodulating characters are controlled by a graft-transmissible shoot factor, and mutant SS2-2 may have similar nodulation mechanism to the former supernodulating nts 382. In all grafts, both supernodulating mutants and Sinpaldalkong 2 maintained the similar balance between above ground and below ground parts regardless of significant differences in partitioning of dry matter into root and nodule between supernodulating mutants and Sinpaldalkong 2.

• Journal of Korean Society for Atmospheric Environment
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• v.22 no.5
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• pp.653-660
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• 2006

Due to the stronger exhaust emission regulations and the introduction of advanced technology in Diesel engine, the specific Diesel particulate matters have decreased by about one order of magnitude since the 1980's. In recent years, particle number emissions rather than particulate mass emissions have become the subject of controversial discussions. Recent results from health studies imply that it is possible that particulate mass does not properly correlated with the variety of health effects attributed to Diesel exhaust. Concern is instead now focusing on nano-sized particles. This study has been performed for the better understanding about the Diesel nano-particle measurement and size distribution characteristics in the exhaust system of a turbo charged Diesel engine. A scanning mobility particle sizer(SMPS) system was applied to measure the particle number and size concentration of Diesel exhaust particles. As the experimental results, the number concentrations in the particle size (Dp<200 nm) were very sensitive to dilution conditions. Specially the changes in nano-particle number concentrations(Dp<50 nm) increased along the downstream of exhaust flow. Also we found the dilution conditions were influencing the condensation of SOF and $H_2O$ during dilution and cooling of hot exhaust.

• Fisheries and Aquatic Sciences
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• v.19 no.2
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• pp.9.1-9.7
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• 2016

This study was conducted to identify the general conditions for the isolation and in vitro culture of ovary-derived cells in rockfish (Sebastes schlegeli). The effects of three different enzymes on cell retrieval from ovarian tissues were evaluated first, and then the ovary-dissociated cells were cultured under various culture conditions, with varying basal media and culture temperatures, addition of growth factors, and/or culture types. We found that collagenase type I treatment was effective for cell isolation from ovarian tissues. From a total of 42 trials to evaluate the effects of basal media and culture temperatures on cell culture of ovary-dissociated cells, we observed that Leibovitz's L15 medium was more supportive than Dulbecco's modified Eagle's medium for culture, and the cells could grow at all three temperatures tested, 15, 20, and $25^{\circ}C$, at least up to passage 2. However, growth factor addition did not improve cell growth. Introduction of suspension culture after monolayer culture expanded the culture period significantly more than did monolayer culture alone. Our results may provide a basis for developing an in vitro system for S. schlegeli germline cell culture, which will ultimately lead to improvement of the species.

• Journal of the Korea Safety Management & Science
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• v.17 no.4
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• pp.353-363
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• 2015

In unlimited competitive period changed every time, domestic manufacturing industry feels a crisis between China and Japan, who are leaping to manufacturing strong countries with worldwide manufacturing factories. In this situation, many companies make an effort to learn and introduce Toyota production method drawing innovation of production method and reduction of many costs for high quality, but most of cases were failed. The reason for the failure should be that correct understanding and application of TPS corporate culture were insufficient and job attitude was not considered when applying Toyota production system. Therefore, the purposes of this thesis are to arrange major contents based on relative documents of precedent researchers, conduct a survey for employees of middle and small scaled manufacturers who introduced Toyota production system, analyze changes of enterprises' job attitude by introduction of TPS corporate culture and the effects on company's management results through the various analyses for grasping relationship among TPS corporate culture, job attitude and management results, introduce Toyota production system more effectively and suggest measures to maximize company's long-term management results.

• Management & Information Systems Review
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• v.19
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• pp.105-128
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• 2006

In accomplishing the objectives of the hospital organizations effectively the good results of hospital information systems depends upon the usefulness and forms of informations provided by them under certain conditions. This study is aimed at examining how much hospital information systems are influenced by the characteristics of organizations and information systems. The results are as follows. 1. In the viewpoint of variations of organization characteristics, the support of chief executive group, the participation of users, education and training has good effects on satisfaction rates of users and system utilization rates as evaluation instruments of results of hospital information systems. 2. In the viewpoint of information system characteristics, the nearness of information sources, the scopes and qualities of informations has good effects on satisfaction rates of users and system utilization rates as evaluation instruments of results of hospital information systems. Accordingly interests and supports of chief hospital executives are required in order to heighten the results of hospital information systems, and there must be participations of organization members in their construction and performance. Also there must be training and education of members in the hospital affairs in using them. In such a condition of hospital organizations the good results of hospital information systems will be produced. The above concluded things must be taken into consideration importantly in their introduction and development.

• Journal of the Society of Naval Architects of Korea
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• v.41 no.2
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• pp.106-113
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• 2004

The block assembly of ship consists of a certain type of heat processes such as cutting, bending, welding, residual stress relaxation and fairing. The residual deformation due to welding is inevitable at each assembly stage. The geometric inaccuracy caused by the welding deformation tends to preclude the introduction of automation and mechanization and needs the additional man-hours for the adjusting work at the following assembly stage. To overcome this problem, a distortion control method should be applied. For this purpose, it is necessary to develop an accurate prediction method which can explicitly account for the influence of various factors on the welding deformation. Systematic and quantitative theoretical works to clarify the effects of various factors on the welding deformation have rarely been found. Therefore, in this paper, the effects of various factors, such as welding process and gravity on the butt welding deformation have been investigated through a number of numerical analyses. In addition, this paper proposes a simplified analysis method to predict the butt welding deformation in actual plate structure. For this purpose, a simple prediction model for butt welding deformations has been derived based on numerical and experimental results through the regression analysis. Based on these results, the simplified analysis method has been applied to some examples to show its validity.

• Journal of Korean Elementary Science Education
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• v.27 no.3
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• pp.244-251
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• 2008

One of the problems with testing for the presence of $CO_2$ is that the results are not visible. In order to over-come this weak point, a new testing method was developed with BTB indicator equipment, that made the gas visible. After that, the experiment was performed and tested the effects of the new visible equipment. The visible equipment could be adapted to regular class use successfully. Also, it was effective in that it reduced waste of gas, minimized danger potential through use of $CO_2$ canisters and candle-sticks, and also increased knowledge about indicators. The new experimental method and equipment affected the students' interest. It is possible that the students' positive participation was due to their interest in the new apparatus and application of the visual senses. The new system was tested fer its effects on teaching content and helping to produce sustained memory of the content. There were no significant differences between the groups in terms of content learning on initial content memory. However, when students in both groups were tested 4 months later, the visual experiment group sustained memory performance, while the other group showed a significant decrease. Generally, boys score higher than girls in terms of interest and participation in experimental activities. In this case, however, there were no difference between groups. It may have been due to introduction of new equipment and different methods from the textbooks. So, this could increase participation in science using various experiments.

• IE interfaces
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• v.23 no.4
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• pp.286-299
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• 2010

Recently, as concerns about environmental improvement have increased, various environmentally friendly transportation services have been developed and introduced. However, the effect on the introduction of such services has been not analyzed through a systematic methodology and process. Therefore, this research aims at suggesting a framework to analyze the effect of an environmentally friendly transportation service and investigating the validity of the framework. To the ends, a process to analyze the degree of improvement in transportation systems and environments, the linkage with existing policies, and profitability of the service is proposed. In addition, the concept and value of carsharing service, a representative environmentally friendly transportation service are explained and then the effects of the service are examined in terms of the aforementioned analytic areas, respectively. The results of this research can be utilized to provide the validity of a newly developed environmentally friendly transportation service and reflected to the policies of transportation and environment.

• Korean Journal of Child Studies
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• v.33 no.1
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• pp.147-164
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• 2012

The purpose of this study was to firstly, analyze how childcare center directors and parents experienced the 'I-Sarang Card Business' and secondly, to evaluate the effects of the business, and thus to suggest the ways to improve business strategies. The subjects consisted of 104 childcare center directors and 304 parents using the 'i-sarang card' in Gyeonggi province. The surveys were administered to the subjects, and the data were analyzed by means of the SPSS 12.0 program. The major results of this study were as follows : After the introduction of the 'I-Sarang Card Business', parents found the payment of childcare fee to be more convenient than previously and evaluated the effects of 'I-Sarang Card Business' to be more positive than the childcare center directors. On the other hand, childcare center directors had difficulties in taking care of 'I-Sarang Card Business' related administration and their evaluations were therefore more negative. Based on these results, several ways to improve the business were suggested.