• Journal of the Korean Geotechnical Society
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• v.27 no.8
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• pp.31-37
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• 2011

In order to evaluate the effect of matric suction on the strength and deformation characteristics, the unsaturated unconfined compression test is performed for the statical1y compacted silty sand. Specimens used were made under conditions with various initial degrees of saturation. The initial matric suction, matric suction at the peak shear strength and the volumetric deformation during the shear process were measured. From these results, it was found that the initial degree of saturation exerts the influence on the behaviors of suction, peak shear strength and the volumetric deformation. Furthermore, the suction stress($P_s$) which means the apparent cohesion due to matric suction in the unsaturated shear strength could be derived.

• Journal of Internet Computing and Services
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• v.4 no.1
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• pp.75-86
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• 2003

In this paper, we extended hierarchial structure of managed object class to support Role-Based Access Control, and described constraint conditions that have support dynamic temporal function as well as statical temporal function established by management process. And we defined about violation notifications should report to manager when rules violate constraint conditions. Also we presented system architecture that support RBAC with MIB(Management Information Base) of ITU-T recommendation. By access control enforcement and decision function, constraint conditions and activated translation procedure of each roles are described, our system presents dynamic temporal property systematically.

• Journal of Korean Biological Nursing Science
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• v.10 no.1
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• pp.62-68
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• 2008

Purpose: This study was conducted to test the effect of the 12 weeks brisk walking exercise program on body composition, blood pressure, blood glucose and blood lipid for middle-aged woman with obesity. Method: The subject were 25 obese women in 40-64 yr old who were composed of over 30% body fat. For the analysis, descriptive statistics, paired t-test were used for statical analysis with SPSS 15.0. Result: The results were summarized as follows: first, the body weight, body mass index (BMI), % body fat of the obese woman were significantly decreased after implementing the 12 weeks brisk walking exercise program (p<.5). Second, the systolic blood pressure, diastolic blood pressure and blood glucose were significantly decreased after the 12 weeks brisk walking exercise program (p<.5). Third, the serum cholesterol was significantly decreased (p<.05) but serum triglyceride was not significantly decreased the after 12 weeks brisk walking exercise program. Conclusion: These results suggest that the brisk walking exercise program has an effect on decreasing body weight, BMI, percent body fat, blood pressure and serum cholesterol in middle-aged woman with obesity to reduce obesity and prevent chronic disease.

• Journal of the Korean Home Economics Association
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• v.30 no.1
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• pp.149-161
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• 1992

The purpose of this study is to analyze information search activity in purchasing behavior of household electric goods. Qusetionare survey method was used in this research. The sample was taken from 302 housewives living in Seoul, from 9th of Nov. to 20th of Nov, in 1991. Used statical methods were Frequency, Percentage, Crosstab, Anova, and Regression Analysis. The major findings are summarized as follows : 1) Component elements of information search : The means of acquiring information is that friends, neighbors, sales are most. A cause of choosing information is the sequence of satisfaction after using, easiness of interaction. The time in choosing goods is more month. 2) Component element of information search as social economic status housewife : children numbers and means of acquiring information(P<.01), education and a cause of choosing information(P<.05), life cost per month and a cause of choosing information(P<.05), social economic status and a time information search are significant. 3) A perception of risk as searching information : Among searching content of information a price influence a perception of risk. 4) Content of searching information and satisfaction of purchasing experience : Best choice is significant as quality of goods, difference of quality is significant as safety and degree of offering information is significant as a brand. 5) Satisfaction of purchasing experience following practical use of information : Best choice is significant as viewing of an exhibit and opinion of user. Difference of quality is not significant as any vairable. Degree of offer information influence searching pamphlet, searching an advertisement and opinion of user. 6) A perception of risk following source of an information : A perception of risk is most influenced by pamphlet.

• Journal of the Korean Society of Safety
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• v.7 no.1
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• pp.39-45
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• 1992

The impulsive stress and wave propagation of a glass/epoxy laminate subjected to the transverse low-velocity impact of a steel ball are investigated theoretically and experimentally. A plate finite element model based on Whitney and Pagano's theory In consunchon with experimental contact laws is used for the theoretical investigation. The specimens fo, statical indentation and impact test we composed of ［0/45/0/-45/0］$_{2s}$ and ［90/45/90/-45/90］$_{2s}$ stacking sequences and have clamped-simply supported boundary conditions. Finally, these two results are compared and then the impulsive stress and wave propagation characteristics of this laminated composite are studied.ied.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.62 no.6
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• pp.870-875
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• 2013

After introducing diagnosis equipment power failure prevention activities for distribution system have become more active. To do facility diagnosis and maintenance work more efficiently we need to evaluate reliability for the system and should determine the priority line with appropriate criteria. Thus, to calculate risk factor for the power distribution line that are composed of many component facilities its historical failure events for the last 5 years are collected and analysed. The failure statics show that more than 60% of various failures are related to environment factors randomly and about 20% of the failures are refer to the aging. As a strategic evaluation system reflecting these environmental influence is needed, a system on the basis of the probabilistic approach related statical variables in terms of failure rate and failure probability of electrical components is proposed. The figures for the evaluation are derived from the field failure DB. With adopting Bayesian rule we can calculate easily about conditional probability query. The proposed evaluation system is demonstrated with model system and the calculated indices representing the properties of the model line are discussed.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.05a
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• pp.704-707
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• 1999

Partial discharge(PD) in air insulated electric power systems is responsible for considerable power lossesfrom high voltage transmission lines. PD in air often leads to deterioration of insulation by the combined action of the discharge ions bombarding the surface and the action of chemical compounds that are formed by the discharge and may give rise to interference in ommunication systems. PD can indicate incipient failure. Thus understanding and classification of PD in air is very important to discern source of PD. In this paper, we investigated PD in air by using statical method. We classified air discharge with corona, surface discharge and cavity discharge by source of discharge. we used the mean pulse-height phase distribution $H_{qmean}(\psi)$, the max pulse-height phase distribution $H_{qmax}(\psi)$ , the pulse count phase distribution $H_n(\psi)$ and the max pulse height vs. repetition rate $H_{q}(n)$ for analysis PD pattern. We used statistical operators, such as skewness(S+. S-1, kurtosis(K+, K-), mean phase(AP+. AP-), cross-correlation factor(CC) and asymmetry from the distribution.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• v.9 no.2
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• pp.495-498
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• 2005

The study is aimed at searching algorithm upgrading which can automatically compose goods displayed according to the degree of popularity regarding customer's requests, for the purpose of design of an intellectual shopping mall on the net and putting it into force by using classified technical Data-mining and statical analysis including personal information , entrance records and purchase records. This is for the study of strategic marketing. The system can automate the conventional shopping mall system by manual and personal judgements and also suggest a new formation of marketing techniques to strengthen the competition in B2B market which is steeply increasing.

• Transactions of the Korean Society of Automotive Engineers
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• v.2 no.6
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• pp.1-8
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• 1994

To enhance the strength of gears for transmission, Generally caburizing heat treatment is applied. But there are some problems in this technology the distortion of gears during heat treatment process, and the discontinuity of manufacturing process. For these reasons, the high frequency induction hardening process is widely used. This method is one of the surface hardening process to improve the wear resistance and fatigue life of the machine components. In this study, to compare the bending fatigue strength of caburized gear with that of induction hardened gear, bending fatigue testing of gears with two different cases was performed by using an electrohydraulic servo-controlled fatigue testing machine and double tooth bending fatigue test fixture. Fatigue life distributions at constant stress levels were established directly from fatigue data. For gear design, the fatigue strength distribution at specified life is more important. This distribution is obtained by statical transformation from fatigue life distribution. Reliability of bending fatigue strength was estimated by P-S-N curves and Weibull distribution.

• Journal of The Korean Society of Agricultural Engineers
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• v.54 no.3
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• pp.81-89
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• 2012

This paper presents a set of controlled simulated statical and engineering mechanical experiments accessible via the virtual world environment (VWE) and virtual physics lab S/W. Online courses of the university offering courses and/or programs online are growing and the number of students want education in ways which fit their personal places, e-learning is becoming more important and ubiquitous each year. In this study, first of all, question is rather 'How do we execute the learning effectiveness of e-learning courses?' than 'Why does they need e-learnig or VW-learning?'. In particular, is it possible to effectively teach mechanical engineering courses online? The answer was 'No'. So, there is little research on many of these questions. And another important question is 'Is e-learning cost effective?'. For the answer, This research provided that an instructional design model is used to 'How to think and apply the Newtonian forces' in the virtual physics lab S/W. Collected data from student are administered in the spring semester when students studied 'Introduction to Bio-resources and Systems Engineering'. Results show that a cadre of students can take highly interactively physical properties of mechanical engineering in the virtual laboratory environment. Those show that VWE is greater than that of a similar real world presentation or experimental lab, since most of students are delighted to modify and retry modeling works in the VWE.