• Journal of Environmental Science International
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• v.27 no.10
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• pp.809-820
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• 2018

DeNOx experiments for the effects of hydrocarbon additives on diesel SNCR process were conducted under oxidizing diesel exhaust conditions. A diesel-fueled combustion system was set up to simulate the actual cylinder and head, exhaust pipe and combustion products, where the reducing agent $NH_3$ and $C_2H_6/diesel$ fuel additives were separately or simultaneously injected into the exhaust pipe, used as the SNCR flow reactor. A wide range of air/fuel ratios (A/F=20~40) were maintained, based on engine speeds where an initial NOx level was 530 ppm and the molar ratios (${\beta}=NH_3/NOx$) ranged between 1.0~2.0, together with adjusting the amounts of hydrocarbon additives. Temperature windows were normally formed in the range of 1200~1350K, which were shifted downwards by 50~100K with injecting $C_2H_6/diesel$ fuel additives. About 50~68% NOx reduction was possible with the above molar ratios (${\beta}$) at the optimum flow #1 ($T_{in}=1260K$). Injecting a small amount of $C_2H_6$ or diesel fuel (${\gamma}=hydrocarbon/NOx$) gave the promising results, particularly in the lower exhaust temperatures, by contributing to the sufficient production of active radicals ($OH/O/HO_2/H$) for NOx reduction. Unfortunately, the addition of hydrocarbons increased the concentrations of byproducts such as CO, UHC, $N_2O$ and $NO_2$, and their emission levels are discussed. Among them, Injecting diesel fuel together with the primary reductant seems to be more encouraging for practical reason and could be suggested as an alternative SNCR DeNOx strategy under diesel exhaust systems, following further optimization of chemicals used for lower emission levels of byproducts.

• The Journal of the Korea Contents Association
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• v.9 no.12
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• pp.261-269
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• 2009

This study was to analyze the effect of market orientation on service quality and business performance in the firms of private security guards. To attain the goal of the study described above paragraphs, some peoples held in Seoul were set as a collected group. Then, using the purposive sampling method, finally drew out and analyzed 235 peoples in total. The material collection device was the brochure named . The result of reliability check up was here below; Chronbach' $\alpha$=.732. To analyze materials, reliability analysis, SEM were used as statistic analysis techniques. The conclusion based on above study method and the result of material analysis are here below. First, market orientation have influence on service quality. Second, market orientation have influence on business performance. Third, service quality have influence on business performance.

• Clinical and Experimental Reproductive Medicine
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• v.19 no.2
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• pp.163-168
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• 1992

This study was carried out to set up the ovum bank for ovum donation and to determine the best freezing method for human immature oocytes. Human immature follicular oocytes were cryopreserved by slow freezing and rapid thawing method. Immature follicular oocytes were treated by propanediol(PROH) solution by 2 and 4 step method in protocols A & B, respectively. In protocol C, immature oocytes were exposed to sucrose prior to treatment of PROH by 4 step method. We compared survival rate, maturation rate, and fertilization rate of immature oocytes among three protocols. Results were as follows. 1. Oocytes treated by the protocol C showed the highest survival rate( 70.3 %) and maturation rate(34.6%) after thawing. 2. Survival rate of oocytes treated by the protocol C was significantly higher than that of the protocol B after thawing(p<0.05). In conclusion, treatment of oocytes with sucrose prior to expose PROH was the best freezing method. Sucrose may have reduced the toxic effect of cryoprotectant to oocytes. We failed to induce fertilization of oocytes, which were treated by any protocols, by conventional insemination method, but obtained 28.8% fertilization rate by using partial zona dissection(PZD) method. This result suggests that micromanipulation(PZD) of the thawed oocytes before insemination will improve the fertilization rate.

• Journal of Global Scholars of Marketing Science
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• v.7
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• pp.209-238
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• 2001

Objectives of this study were: First, to review the effect of buyer position in power retailer on job performance and store performance. Second, to set up research model specifying relationships between the PAQ dimensions of retailer's buyer, job performance and store performance. Third, to test hypotheses derived from the research model of this study and to establish strategy for managing discount store and department store. Marketing Implications of this study were: First, buyers of power retailers should respond more actively to rapidly changing purchasing situation. Second, job content of buyers in power retailers can be redesigned based upon results of this study. Third, as the size and the length of operation of retailers increase, an innovative system should be invented to enhance the effectiveness of power retailers. Limitations of this study were: First, validity and reliability of data collection methods used in this study were questionable for the lack of past researches in Korea. Second, static research method was employed in this study. Generalization over different time interval was almost impossible from results of this study.

• Journal of Global Scholars of Marketing Science
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• v.9
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• pp.189-201
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• 2002

Objectives of this study were: First, the purpose of this study is to develope the factors affecting private brand based on past researches and to review effects of the consumer perception factors affecting private brand preference. Second, to set up research model specifying relationships among price perception, information search and experience, Quality perception and private brand preference. Third, to test hypotheses derived from the research model of this study and to attempts to explain how to have the effect the private brand preference. Marketing implications of this study were: As a result LISREL analysis, price perception, informations search and experience, quality perception increase and enhance private brand preference. Limitations of this study were: Data collection methods used in this study were questionable for the lack of general analysis in the difference of preference between characteristics of purchaser and characteristics of non-purchaser exactly because our sample was only limited to Changwon, Masan and Jinhae. So future study has to include samples in other regions.

• The Korean Journal of Financial Management
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• v.24 no.1
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• pp.85-107
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• 2007

In this study, I analyzed determinant factors of mutual fund return. The samples was distributed into three types according to the ratio of included stocks in funds. The proxies of mutual funds were set up three ways(returns of fund). As a result of the analysis, I found that growth positively affect to fund return, abnormal return and adjusted abnormal return in all samples. While, according to three types of sample, expected and unexpected fund cash flows had differently effect on fund return. Inferentially, it seemed that the ratio of included stocks in fund was the cause of that. But price pressure hypothesis are not supported. In conclusion, it was not found the possibility of stock market disturbance in this analysis.

• Physical Therapy Korea
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• v.19 no.3
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• pp.1-10
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• 2012

The aim of this study is to compare measurements of abdominal muscle thickness using ultrasonography imaging (USI) to those using a special transducer head device, during five different trunk stabilization exercises, ultimately to determine which exercise led to the greatest muscle thickness. Thirty eight healthy subjects participated in this cross-sectional study. The five types of trunk stabilization - i.e., a sit-up on the supine, an upper and lower extremity raise with quadruped on the prone, a leg raise in sitting on the ball, trunk rolling on the ball, and balance using sling on the prone position - were each performed with an abdominal draw. The thickness of the abdominal muscle - including the transverse abdominal (TrA), internal oblique (IO), and external oblique (EO) - was measured by USI with a special transducer head device, at rest and then at contraction in each position. Data were analyzed using one-way repeated ANOVA with the level of significance set at ${\alpha}$=.05. The results were as follows: 1) the TrA thickness was statistically significant (p<.05), whereas the IO and EO thicknesses were not (p>.05); 2) among the five types of trunk stabilization, TrA thickness significantly increased with the balance using a sling in the prone position, (p<.05), whereas no significant difference was noted for the four types of trunk stabilization (p>.05); 3) reliability data showed that there was a high degree of consistency among the measurements taken using the special transducer head device (ICC=.92). In conclusion, the balance using a sling in the prone position was more effective than any of the four other types of trunk stabilization in increasing TrA thickness in healthy subjects.

• Korean Journal of Construction Engineering and Management
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• v.13 no.3
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• pp.78-88
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• 2012

Previous construction failure researches were focused on the utilization plan based on failure information and development of failure classification. However, it has limitation to set up the plan for prevention of construction failure due to the lack of the number of on-site staffs. In order to prevent effectively construction failure, a prevention plan should be established through quantitative evaluation of failure causes. The purpose of this study is to suggest the assessment method for selection Critical Management Factor(CMF) and to analyze the CMF on the apartment structural framework using FMEA(Failure Mode and Effective Analysis) which is one of the methods of quantitative evaluation. The element of risk evaluation separated degree of failure risk and prevention respectively. The assessment method for selection of CMF can be utilized for planning proactive solutions on the failure, and it can be also selected critical factors about each project phases, type of facility and construction work.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.31 no.6D
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• pp.867-874
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• 2011

The ballast abrasion occurs on the ballasted track upon bridges more than soil roadbed because the track vibration occurs a lot in the ballasted track upon bridges due to girder vibration when a train's weight is loaded onto track even though the identical ballast is used. The phenomena of mud pumping especially, which occurs when drainage is not properly secured for heavy rain, leads to the increase of maintenance work load and the decline of ride comfort. The ballast thickness range in domestic railroad construction rule is uniformly set up according to the design speed of railroad and passing tonnage of train without considering field conditions which is considered in foreign railroad companies. The purpose of this study is to verify the effect of vibration decrease by measuring the acceleration, displacement and ride comfort of ballasted track with the change of ballast thickness on the ballast tracked bridges and to suggest the optimal height of ballast on the Yocheon Bridge built for the test in Honam Line.

• Korean Journal of Community Nutrition
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• v.22 no.3
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• pp.218-227
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• 2017

Objectives: The purpose of the study was to develop dietary change program items that could be used to improve dietary life of the elderly and investigate their validity. Methods: The survey was were analyzed by SPSS program (Ver. 21) and descriptive statistics was performed; a t-test, ${\chi}^2$ test, One-way ANOVA and Friedman test were used to determine the priority. Results: Programs for feeding senior citizens that need to be newly established are largely divided into two fields, namely, application of welfare facilities and application of home care, classified into large, medium and sub-classes. The large class was divided into nutrition management, sanitary control, and other health management. The medium class of nutrition management was divided into nutrition education, nutrition intervention, and menu management and supply. The sub-class was composed of division into application of welfare facilities for the elderly and application of home care for the same age group. Responses showed high rate saying that all the categorized items were necessary and valid. With respect to expectation effect on a community program for old people feeding, 'yes' was 65 people (55.6%) showing very high expectation toward the question whether a community program for old people feeding are newly set up. Conclusions: It is believed that nutrition for the aged will be improved and it will be a help not only to a small facilities without obligation of employing a dietician but also to the aged at home if a community program for old people feeding are newly established.