• Transactions of the Korean Society of Automotive Engineers
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• v.3 no.1
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• pp.54-64
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• 1995

The effects of swirl on early flame development and late combustion characteristic were investigated using a high speed single-shot visualized 51 engine. LDV measurements were performed to get better understanding of the flow field in this combustion chamber. Spark plugs were located at half radius (R/2) and central location of bore. High speed schlieren photographs at 20,000 frames/sec were taken to visualize the detailed formation and development of the flame kernel with cylinder pressure measurements. This study showed that high swirl gave favorable effects on combustion-related performances in terms of the maximum cylinder pressure and flame growth rate regardless of spark position. However, at R/2 ignition the low swirl shown desirable effects at low engine speed gave worse performances as engine speed increased than without swirl. There were distinct signs of slow-down in flame growth during the period when the flame front expanded from 2.5mm in radius until it reached 5.0mm apparently due to the presence of ground electrode. There seemed to be heat transfer effect on the flame expansion speed which was evidenced in high swirl case by the slowdown of the late flame front presumably caused by relatively large heat loss from burned gas to wall compared with low- or no-swirl cases.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2006.11a
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• pp.351-354
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• 2006

In underwater environment, the control of AUV is difficult, because of the existence of parameter uncertainties and disturbances as well as highly nonlinear and coupled system dynamics. The requirement for the simple and robust controller which works satisfactorily in those dynamical uncertainties, call for a design using the PD or sliding mode controller. The PD controller is very popular controller in the industrial field and the sliding mode controller has been used successfully for the AUV controller design. In this paper, the two controllers arc designed for ISiMI(Integrated Submergible Intelligent Mission Implementation) AUV and the performances are compared by numerical simulation under the modeling uncertainty and disturbances. The design process of PD and sliding mode controller for ISiMI AUV and simulation results are included to compare the performances of the two controllers.

• Korea Journal of Hospital Management
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• v.22 no.4
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• pp.74-86
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• 2017

Purposes: This study was performed to understand the recognition about accreditation motives, support within the hospital and accreditation survey process for the hospitals that participated in the accreditation program and to find out whether these factors are related to hospital management performances, so that the study can suggest plans for activation and development of the accreditation program. Methodology: This study was performed targeting 98 hospitals answered th the survey among 189 acute care hospitals that acquired accreditation from December 2010 to February 2014. For data analysis, frequency analysis, ${\chi}^2$-test, reliability analysis, ANOVA, Kruskal-Wallis H test and multiple regression analysis with SPSS 21.0 were used. Findings: The hospitals that had staff in charge of patient safety had bigger hospital culture change than those that didn't have(p<.05). In addition, the hospital culture change was bigger as internal motives were bigger, and as CEO's will was bigger(p<.05). Meanwhile, as maintenance rate of internal management after accreditation was higher, and as CEO's will was bigger, process improvement level was higher(p<.05). The quality improvement and patient satisfaction level were higher as CEO's will was bigger, and as suitability of survey process was recognized to be high(p<.05). As a result of analyzing the factors that affect hospital management performances with hospital culture change, process improvement and quality improvement combined, as internal management maintenance rate was higher, as CEO's will was bigger, and as suitability of survey process was higher, performances were higher(p<.05). Practical Implications: Hospitals need to reinforce internal motives to improve internal competences such as the whole system maintenance opportunity and staff training. In addition, the will of hospital director is most important, and if there is hospital director's interest in quality improvement and improvement intention definitely, employees voluntarily participate in and cooperate with the accreditation program, so that prompt medical service provision and high quality of medical services can be guaranteed, leading to hospitals' management performances.

• Korean Management Science Review
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• v.17 no.1
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• pp.1-15
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• 2000

This study examined the role effect provided by top management and team operations in applying the inner capabilities of R&D manufacturing and marketing to the performances of new product development. In examining the relationships of the factors in the study direct and indirect effects were determined in the structural model. Implications for new product development were made in the conclusive section.

• Journal of the Korean Operations Research and Management Science Society
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• v.17 no.1
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• pp.1-1
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• 1992

This study examined the role effect provided by top management and team operations in applying the inner capabilities of R&D manufacturing and marketing to the performances of new product development. In examining the relationships of the factors in the study direct and indirect effects were determined in the structural model. Implications for new product development were made in the conclusive section.

• Bulletin of the Korean Space Science Society
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• 2004.10b
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• pp.316-320
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• 2004

This paper describes Ka-band antenna performance analysis of COMS satellite. The key parameters of the antenna system are optimal antenna diameter, feed horn type and horn size, F/D, and the coordinate of offset horns. The paper deals with the method to determine design core parameters of optimal antenna diameter, feed horn type and horn size, F/D, and the coordinate of offset horns, and the performances of design result.

• Korean Journal of Community Nutrition
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• v.11 no.1
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• pp.116-123
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• 2006

The purposes of this study were to develop a tool for assessing internal branding performance and to identify the difference of internal branding performance between local and international hotels. The internal branding performance measure was developed through literature studies and face-to-face in-depth interviews with managers in various departments of 5 deluxe hotels. The questionnaires were distributed to 460 employees in food and beverage departments of 11 deluxe hotels in Seoul, and a total of 398 questionnaires were used for analysis ($86.5\%$). The statistical analyses were completed using SPSS Win (12.0) for descriptive analysis, reliability analysis and t-test, and AMOS (5.0) for confirmatory factor analysis. The results of this study showed that the measure developed in this study was reliable and valid for assessing internal branding performances of hotels. In addition, the internal branding performances of hotels were high at understanding of brand dimensions and relatively low at work and organizational culture and human resource management dimensions, and local hotels showed lower levels of performance than international hotels at the dimensions of work and organizational culture (t = -3.801, P < 0.001) and human resource management(t = -5.397, p < 0.001). In conclusion, it is considered that a strong internal branding strategy should be established for successful brand management, and the practical measure for internal branding performance would be a key factor.

• Journal of the Korean Society for Precision Engineering
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• v.26 no.3
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• pp.73-80
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• 2009

In accordance with the trend for high-speed multi-axes, and the increasing technical sophistication of machine tools, thermal deformation has become an important factor in the accuracy of machine tools. It was analyzed that thermal deformation error accounts for about 70% of all errors made with machine tools. For precise temperature control, both cooling and heating should be implemented. A hot gas bypass type cooling cycle method has a simplified structure and temperature control accuracy to with in ${\pm}0.1^{\circ}C$. In this study, the performances of oil cooler system, including temperature controllability according to hot gas floe and preset temperature sustainability according to temperature load, were tested. It is expected that this study will contribute to the development and performances of oil cooler system, which could minimize thermal errors and improve the quality of precision machine tools.

• Journal of Technology Innovation
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• v.12 no.1
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• pp.161-188
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• 2004

The objective of this research is to evaluate the Creative Research Initiative Program (CRI), a national R＆D program funded by the Ministry of Science ＆ Technology in Korea. The evaluation of CRI covers the following research questions; 1) Have it set a unique position and characteristic distinguished from other government-funded R＆D programs\ulcorner 2) Are the achievements of the program relevant to its goal\ulcorner 3) What is its performances and how much is it achieved its goal\ulcorner The results are the followings; 1) CRI is perceived as a pure basic research, distinguished from other national basic research programs, such as the Coal Oriented Basic Research Program and the SRC and ERC. 2) CRI is a well-adapted R＆D program in confront of the environmental changes and R＆D needs, as well as follows the planned R＆D areas. 3) CRI have performed well in the raising-up world-class research leaders and the nation-wide diffusion of creative R＆D culture, while it got few performances in the overcoming the limitation of the existing technologies and the independent development of original key technologies for future industries. However, the duration of the program, 5 year, is too short to expect concrete outcome, such as creating original technologies. Many of the outcomes of CRI gets a lot of attention from top class scientists in the world, it is expected to generate various R＆D performances in the future.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.21 no.3
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• pp.203-207
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• 2008

Chemical mechanical polishing (CMP) allows the planarization of wafers with two or more materials. There are many elements such as slurry, polishing pad, process parameters and conditioning in CMP process. Especially, polishing pad is considered as one of the most important consumables because this affects its performances such as WIWNU(within wafer non-uniformity) and MRR(material removal rate). In polishing pad, grooves and pores on its surface affect distribution of slurry, flow and profile of MRR on wafer. A subject of this investigation is to apply CMP for planarization of shallow trench isolation structure using microstructure(MS) pad. MS pad is designed to have uniform structure on its surface and manufactured by micro-molding technology. And then STI CMP performances such as pattern selectivity, erosion and comer rounding are evaluated.