• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.25 no.5
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• pp.261-268
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• 2013

Technologies for preventing contaminants deposition are a key issue in a modern duct system. When particulate matters deposit inside the exhaust pipes, which are widely used in the Urea-SCR system to reduce $NO_x$ emission from heavy duty diesel engines, many problems arise associated with increased flow resistance and corrosion. Therefore, the development of the urea deposition avoidance technologies is being treated as an important issue of the Urea-SCR system. An analytical study was carried out to investigate the effects of the wall flow around the mixer with the variation of the mixer housing surrounding and supporting the mixer, which is designed to increase the wall flow and then to reduce droplet deposition. The housing angles and the position of the mixer were changed：angles of $0^{\circ}$, $1^{\circ}$, $2^{\circ}$, and $3^{\circ}$, and mixer positions of 0 L, 0.5 L, and 1 L. The axial velocity distributions, maximum velocity, the half-width, and momentum distribution of the wall flow were investigated to examine the effect of the mixer-housing assembly geometry.

• 대한예방의학회:학술대회논문집
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• 2000.10a
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• pp.27-28
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• 2000

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.11 no.1
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• pp.56-69
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• 2001

Objectives : This study was designed to develop and standardize a checklist for ergonomic risk factors, and to provide ergonomic guidelines for managing cumulative trauma disorders (CTDs) in automobile assembly lines. Methods : The Checklist for Ergonomic Risk Factors (CERF-1) was developed based on the results of previous studies, and then modified after performing pilot study. Information on the symptoms possibly related with CTDs was obtained using a self-reported Questionnaire from 465 automobile assembly workers. Their job conditions were examined to assess risk factors through both direct observation and video analysis. Results : Rate of detecting risky job through CERF-1 was 85.6%, and was similar to that (88.8%) by Occupational Safety and Health Adminstration(OSHA) checklist but higher than that (63.7%) by American National Standards Institute(ANSI) Z-365. Relationship of the exposure scores derived from CERF-1 with levels of symptom was greater (r=0.49) than OSHA (r=0.28) and ANSI Z-365 (r=0.22). Considering the relationship, jobs scoring higher than 16 could be classified as the Risk Job. and lower than 16 as the Low Risk Job. Sensitivity and specificity of the Risk Job were 92.5 % and 31.5 %, respectively. Odds ratio (OR) after age adjustment was 5.69 (95 % confidence interval 3.15-10.29) for the Risk Job, and these ORs were significantly different from those of the Low Risk Job. The exposure scores were Quite valid, in that the scores at the main survey were significantly correlated with those at the follow-up survey, as suggested by test-retest(r=0.88) and inter-rater reliability(r=0.80). Conclusions : The CERF-1, developed in this study, will be an efficient tool for evaluation of risk jobs for CTDs in automobile assembly lines, and can be used easily by health care providers.

• Journal of the Korean Society of Marine Environment & Safety
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• v.19 no.5
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• pp.552-560
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• 2013

In this paper, an optimization algorithm for the block assembly accuracy control assessment is proposed with consideration for the current block assembly process and accuracy control procedure used in the shipbuilding site. The objective function of the proposed algorithm consists of root mean square error of the distances between design and measured data of the other control points with respect to a specific point of the whole control points. The control points are divided into two groups: points on the control line and the other points. The grouped data are used as criteria for determining the combination of 6 degrees of freedom in the registration process when constituting constraints and calculating objective function. The optimization algorithm is developed by using combination of the sampling method and the point to point relation based modified ICP algorithm which has an allowable error check procedure that makes sure that error between design and measured point is under allowable error. According to the results from the application of the proposed algorithm with the design and measured data of two blocks data which are verified and validated by an expert in the shipbuilding site, it implies that the choice of whole control points as target points for the accuracy calculation shows better results than that of the control points on the control line as target points for the accuracy of the calculation and the best optimized result can be acquired from the accuracy calculation with a fixed point on the control line as the reference point of the registration.

• The Bulletin of The Korean Astronomical Society
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• v.38 no.2
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• pp.48.1-48.1
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• 2013

We present galaxy luminosity functions (LFs) of subgroups in the Ursa Major cluster. The membership of galaxies is determined by radial velocities which are compiled from the SDSS and NED. We found that the faint end slope (${\alpha}$) of the LF of all sample galaxies in Ursa Major is ${\alpha}=-1.13$. This is consistent with previous result, but shallower than that of the Virgo cluster. Interestingly, the subgroups in Ursa Major show different slopes in their LFs. The NGC 3992 and NGC 4111, the massive subgroups in the Ursa Major cluster, exhibit steep slopes of their LFs comparable to that of the Virgo cluster. On the other hand, less massive group (NGC 3877) shows a very shallow slope of -0.84. Based on the results, we discuss the evolution of galaxies and the assembly history of the Ursa Major cluster.

• Bulletin of the Korean Chemical Society
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• v.25 no.11
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• pp.1711-1713
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• 2004

• The Korean Journal of Emergency Medical Services
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• v.11 no.3
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• pp.17-30
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• 2007

Accidents occur frequently and that the date of the emergency situation and the people a good quality of life to actively respond to the emergency scene in the line of business activities and given their lives silently. 1st EMT's is currently the most jobs in the ability to work within a hospital that can be verified by expanding employment opportunities than the rate of youth unemployment and a sharp alleviate part of the current emergency medical institution performing the duties within the contents of this communication in a Emergency patients reflected in the rates for schools that can be revitalized as part of the emergency medical system(part of the emergency medical workers) for the completion of the law concerning emergency care, if you want the current laws and enforcement rules are to be improving. Under the current provisions in law concerning emergency care, and enforceable rules on enforcement issues and identify practical issues for consideration and improvements to enumerate the reasons for the demotion, the following conclusions can be sure until they improve. In addition, the National Assembly recently passed a bill AED use, and enforceable rules to enforce party that can teach AED necessarily a grade, including 1st EMT's to protect people's lives and to actively deal with the emergency situation so that it can be. Resolving these issues in the country where the emergency medical system can create a foundation for the advancement of emergency patients can get a good length of life, opens.

• Clean Technology
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• v.20 no.2
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• pp.141-145
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• 2014

In this study, we studied optical properties on the layer-by-layer (LbL) assemblies consisting of Au nanorods and organic dyes. For this purpose, poly (allylamine hydrochloride), PAH and poly (styrene sulfonate), PSS were selected as ionic polymers and rhodamine B isothiocyanate (RB) was utilized as an organic dye based on its spectral overlap with plasmon band of Au nanorods. In the view point of assembling methods, RB was covalently attached to PAH, then, LbL structure of Au [PSS/PAH]2/PSS/PAH-RB was prepared by sequential coating of PAH, PSS, PAH-RB on Au nanorods. Since the prepared LbL assembly exhibits both plasmonic and fluorescent properties, we studied the mutual nanorod-dye properties by dissolving Au nanorods.

• Clinical and Experimental Pediatrics
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• v.51 no.12
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• pp.1275-1281
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• 2008

National Immunization Program (NIP) in korea is regulated by government for effective prevention of infectious diseases since 1954. But the program is only performed in public health center, so many people had various complaints such as inconvenience to use public center, high cost when vaccinated in private medical organization and lack of speciality and registration etc. In this reason, it was very difficult to raise the vaccination rate to 95 percent, infectious disease preventable rate. With this background national assembly and government try to expand the NIP coverage both public health center and private medical organization with increasing budget from 2009. So in this paper an overview and preparation of Korean pediatrician according to the expanding plan of NIP are described.

• Journal of Korean Society for Geospatial Information Science
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• v.23 no.2
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• pp.17-26
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• 2015

River corridors facilitate dispersal and movement and prevent local extinction of species. As a result of stream restoration projects, which include installation of waterfront and flood control structures, the number of animals, which rely on river corridor, is decreasing. For the study, factors affecting fish assembly were extracted by a species distribution model with the fish data collected from the Seom River in Hoengseong County and City of Wonju, Ganwon Province, Korea between March to October 2013. The riparian connectivity was assessed using species richness and rarity. According to result of the field survey, there were 38 species and 7,061 individuals for fish. The analysis suggests the following. Firstly, factors affecting fish richness in species distribution model results are shown to be velocity, riffle, riparian width, and water width. The accuracy of the model proves to be suitable with the correlation coefficient of 0.83 and MAPE of 19.2%. Secondly, the low rarity area is shown to be straight streams in Jeon river near to Hongseong County and the high rarity area to be streams with large width, existing alluvial area at channel junction between Jeon river and Seom river. Thirdly, according to connectivity results, areas where weirs are installed or riparian buffer area is removed showed low connectivity. The areas where farmland near riparian and forest areas showed high connectivity. The results of this study can be utilized to improve current facilities and enhance connectivity as a restoration guide.