• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2007.04a
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• pp.148-151
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• 2007

We made two injectors that were equal to all design except for existence or nonexistence of swirl chamber of fuel part, because we want to find cooling characteristics at the injector face according to existence or non existence of swirl chamber of fuel part. And we set regenerative cooling channel in injector face for protecting injector face for prolonged combustion time. Two injectors were performed hot firing test, and then we compared cooling characteristics of two injectors. Also we compared O/F ratio effects on cooling characteristics and combustion characteristics.

• Clean Technology
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• v.12 no.4
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• pp.217-223
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• 2006

The operating variables of a desorption step were experimentally investigated tor the cycle of the process made up of benzene adsorption, steam desorption, and drying step. The effect of adsorbent regeneration depending on existence and nonexistence of drying step was studied by breakthrough curves obtained in the adsorption step of the second cycle. The duration of drying step was determined by the experimental results. In case that the amount of nitrogen gas was fixed, the regeneration efficiency increased with the amount of steam. However, the effect of steam decreased as the amount of nitrogen increased. Therefore, it would be possible to predict the optimum amount of steam comparing the amount of nitrogen gas with amount of steam in economic view.

• The Journal of Pediatrics of Korean Medicine
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• v.19 no.2
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• pp.137-152
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• 2005

Objective : As the meaning of collective medical examination, the purpose of this study is to investigate distribution of weak children by measurement according to the five group of weakness (Lung, Heart, Pancreas, Liver, Kidney), and the relationship between the five group of weakness and the Growth failure on primary school children. Methods : This study is composed of 1078 children who attend A primary school in ${\bigcirc}{\bigcirc}$ city. They are divided into 6 groups by grade and for the purpose of effective comparison, The five weak symptoms are studied to determine the association with growth stature among children and we standardize the weak children's height into percent according to age. Results: When each weak children controled grade, sex, body-weight, existence or nonexistence of personal history, physical exercise so on, relatively group of weakness for kidney is statistically less then opposite group and the rest of the people statistically have no significant difference. Conclusions: From the above result, it is suggested that the statistical relationship between the weakness for kidney and growth(p<0.001). It looks forward to have contributed to collective medical examination and children's health care by oriental medical treatment.

• Convergence Security Journal
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• v.8 no.4
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• pp.191-197
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• 2008

A safe computer environment is necessarily required for computer users, because of a damage is widely increased by a malicious software such as the warm, virus and trojan horse. A general vaccine program can detect after the malicious software intruded. This kinds of the vaccine program show good result against a malicious code which is well known, however, there is no function in the vaccine or not enough ability to detect an application software which a malicious code included. So, this paper proposes an application verification system to decide existence and nonexistence of a malicious code in the application software. The proposed application verification system with a mechanism that grasps the flow type of malicious code, can make a reduction of a damage for computer users before the application software executed.

• Journal of the Korean Society of Clothing and Textiles
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• v.27 no.3_4
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• pp.441-451
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• 2003

The purpose of this study was to find out evaluative criteria of cyber store toward shopping orientation, purchasing experience and demographic factors of consumers to visit cyber store. This study surveyed consumers who have an experience of using cyber store and judgment sampling was used. The respondents were 240 men and women living in the metropolitan area of Seoul and Gyeonggi province. Research method was measured by clothing shopping orientation (utilitarian and hedonic factors), cyber store evaluation criteria (convenience, quality & trust and product character factors), purchasing experience(existent and nonexistent) and demographic factors. For data analysis, descriptive statistics, factor analysis, cluster analysis, ANOVA, t-test, Duncan test, and reliability analysis were conducted. The results were as follows: 1. Evaluative criteria of cyber store were considered importantly in order of possibility of exchange and refund, stability of personal information security, substance of quality degree of product and service and store. 2. Among shopping orientation groups, there were significant differences in all evaluative criteria of cyber store: convenience, quality & trust and product character of store. 3. Among groups toward existence and nonexistence in a purchasing experience, there were significant differences in convenience and quality & trust of store. 4. Among Demographic factors(gender, job, education and income) there were significant differences in convenience and quality & trust of store.

• Transactions of the Korean Society of Automotive Engineers
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• v.23 no.3
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• pp.352-359
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• 2015

This study investigates the analysis result of structure and fatigue due to the models of the hub space with bolt joint at wheel and the existence or nonexistence of hub ring as the part of suspension system of vehicle. As the static analysis result, the structural vulnerability can be found at hub bolt and the center of wheel at three models. Model 2 and 3 have nearly same deformation and model 1 can be endured at the least load among three models. As the fatigue analysis result, fatigue lives of three models are same at the severest load of SAE bracket history. As many screw threads of weak bolts are jointed in case of model 1, model 1 is shown to be the weakest at fatigue damage among three models. By the result of this study, model 1 with bolt joint becomes most weakest among three models. As model 2 with no hub ring and model 3 with hub ring have the nearly same states of analysis results, hub ring is shown to have no influence on the safety of automotive driving.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.06a
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• pp.25-26
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• 2007

In this paper, we studied the shadow effect which is one of environmental cause for hot-spot phenomenon on PV by considering electrical effects. We fabricated PV module in case of existence and nonexistence of bypass diode. And maximum output power and thermal distribution was analyzed by shadowing solar cell by increase of 5%. From the results, the PV module's(without bypass diode) maximum output power was reduced by hot-spot gradually. But the PV module's(with bypass diode) maximum output power had no reduction by operation of bypass diode, though solar cell is shadowed more than 60%. The solar cell temperature of PV module(without bypass diode) was $10^{\circ}C$ higher compared to module's one. This is a reason for shortening of durability of PV module.

• Hwankyungkyoyuk
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• v.21 no.2
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• pp.40-50
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• 2008

The purpose of this study was that verify the difference of pro-environmental behavior according to be present or not of experience environmental education for developing pro-environmental and show basic material to prepare efficient operation plans of experience environmental education is based on factor which effect of pro-environmental behavior difference according to the types. Elementary schools were divided through existence and nonexistence of an experience environmental education than I was checked up the pro-environmental behavior of students, who joined in different environmental educations each other. It was analysis by dividing into an environmental education of school, an educator (teacher, environmental-interpreter), and fields for environmental education (school inside and outside) to know types of experience environmental education. In result, elementary schoolers who experienced an experience environmental education at school class, had higher an environment-friendly behavior and elementary schoolers, who experienced an experience environmental education at class from environmental-interpreter, had higher an environment-friendly behavior by and large. As a result, this study showed that the area based on their residential quarter and an experience environmental education with realistic plans to connect with social environmental education for developing pro-environmental carrying out the most positive effect.

• Progress in Superconductivity and Cryogenics
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• v.20 no.4
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• pp.55-59
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• 2018

Currently, the development of industry makes needs larger electric supply. Providers must consider the efficiency about losses and reliability of the system. In this case, DC power system can save electrical energy; long-distance transmission line losses. Relevance to switch technology with a voltage-source converter (VSC) in AC-DC conversion system have been researched. But, protection device of DC-link against fault current is still needed to study much. VSC DC power system is vulnerable to DC-cable short-circuit and ground faults, because DC-link has a huge size of capacitor filter which releases extremely large current during DC faults. Furthermore, DC has a fatal flaw that current zero crossing is nonexistence. To interrupt the DC, several methods which make a zero crossing is used; parallel connecting self-excited series LC circuit with main switch, LC circuit with power electronic device called hybrid DC circuit breaker. Meanwhile, self-excited oscillator needs a huge size capacitor that produces big oscillation current which makes zero crossing. This capacitor has a quite effective on the price of DCCB. In this paper, hybrid self-excited type superconducting DCCB which are using AC circuit breaker system is studied by simulation tool PSCAD/EMTDC.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.3
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• pp.201-208
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• 2021

This study aimed to identify the key factors that affect the financial market performance (Price-Earnings Model) through a sample of 35 public shareholding industrial companies on the Amman Stock Exchange for the period 2010-2019, using statistical models and methods, such as the Simple Linear Regression Model, Correlation Coefficient, and dispersion board. The study results showed the nonexistence of a statistically significant effect between the intellectual capital and market value added (MVA) and market performance. Results also showed a statistically significant positive effect between financial leverage (FL) and the market performance, where the interpreted variation reached 64%. It showed from the analysis results that the relationship between (MVA) and market performance (P/E) agrees with the study hypotheses, while the result related to (FL) disagrees with the study hypotheses. The study recommends that public shareholding industrial companies should focus more on intellectual capital and show its value in the annual financial statements and reports, and those companies that have high profitability and the chance to hold gains and profits should rely less on debt and more on retained earnings, due to the high risk of debt and in line with the present unstable circumstances in Jordan, especially in light of the global Covid-19 crisis.