• Journal of Digital Contents Society
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• v.2 no.1
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• pp.9-19
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• 2001

Web robot is an important Internet software technology used in a variety of Internet application software which includes search engines. As Internet continues to grow, implementations of high performance Web robots are urgently demanded. For this, researches specially geared toward performance scalability of Web robots are required. Hoover, because researches are focused mostly on addressing issues related to commercial implementations, scientific researches and studies are not still made on the performance scalability. In this research, Ive choose a Web robot model implemented by fork-join based. multiprocesses. With respect to the model, we evaluate the effect on the collection efficiency that the timeout values set to requests from Web robots to Web servers have. Also, we analysed the behaviors of Web robots by comparing the execution time between the URL extraction and the uniqueness checking for the extracted URLs. as well as by comparing between the computation time and the network time. Based on the analysis result, we suggest the direction for the design of high performance Web robots.

• Journal of Digital Convergence
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• v.11 no.11
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• pp.37-52
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• 2013

Prior to full-scale implementation of smart grid, the Korean government is conducting a smart grid testbed in Jeju island. However, the participants of the ongoing program are skeptical about the success of the expansion of smart grid. The concern rises from various reasons; the limits of the Korean electricity market mainly led by both the government and KEPCO, high stability and reliability of the existing electricity grid, insufficient utilization of renewable energy, and public fear of raised electricity bills. Five key issues in regards to facilitating the Korean smart grid market are extracted and evaluated. The issues are conflict of interest among participants, the effect of introducing real-time pricing, lack of customer participation of demand response, and absence of business models.

• Journal of The Korean Association For Science Education
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• v.37 no.4
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• pp.693-703
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• 2017

In this study, 37 elementary, middle, and high school science teachers attending graduate schools of education were surveyed about their thoughts about the difficulty of teaching science units and teaching methods to teach these units to students. After experiencing the activity of making new teaching tools using scratch, we tried to confirm the development of TPACK among the teachers. Through the questionnaire survey for elementary, secondary, and high school science teachers, we selected the unit of Planetary Movement of the Solar System as a unit that is difficult for teachers to teach. We gave them the experience of instruction on tool making process for implementing a planetary operation model using scratch. Then, based on the questionnaires and class presentations, we analyzed the change of awareness about technology introduction and the development of their TPACK. As a result, most of the teachers showed changes of perceptions related to TK, TCK, TPK; the use of programming for creating teaching materials enhances teachers' understanding of the teaching contents; the teachers were convinced that students would develop the ability to construct models that fit observational phenomena; they thought that there would be a positive educational effect in the positive domain.

• Journal of Service Research and Studies
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• v.7 no.2
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• pp.53-66
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• 2017

This study was conducted to develop core competence model for bancassurance personnel. Prior studies have conducted both FGI and specialist workshops to explore and define the necessary competencies for bancassurance personnel. As a result, 17 such competencies have been identified. A survey involving 105 bancassurance personnel from affiliated banks was conducted to compare perceived importance with retention levels of the aforementioned required competencies. SPSS 20.0, T-test, Borich analysis, and The Locus for Focus model were utilized to confirm education priority and for statistical analysis. The bancassurance personnel competencies that were rated as high in importance and retention were as follows: relationship building, interpersonal understanding, proactive execution of duties, and introspective self-confidence. In chronological order, the educational priorities for the required competencies were found to be as follows: professionalism, proposal capability, achievement orientation, and relationship building.

• Journal of the Korean Magnetics Society
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• v.8 no.4
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• pp.224-230
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• 1998

The relationships between R-H curves of gaint magnetoresistance (GMR) spin valve trilayer films and M-H curves of each magnetic layer consisting of the trilayer films were analyzed and simple formula representing the relations between the curves were suggested for theoretical analysis and study of magnetoresistance (MR) in those films, especially where the MR is from the difference of coercivity. Using two kinds of NiFe/Cu/Co films, which had been deposited on Cu(50 $\AA$)/Si(111, 4$^{\circ}$ tilt-cut) and Cu(50 $\AA$)/glass, R-H and M-H curves were measured and compared with the calculated ones, which were obtained by appying the M-H curves of single NiFe and Co films, deposited on the same substrates, to the previously reported single-domain and multi-domain models. The calcuated ones were well consistent with the measured ones and the suggested simple relationships between R-H and M-H curves are thought to be very useful for the deep understanding of MR behavior and the reasonable approach to improve MR properties in GMR spin valve trilayer films.

• Journal of the Korea Convergence Society
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• v.8 no.9
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• pp.331-338
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• 2017

The purpose of the present convergence study is to investigate the relationship among self control, fairness, and happiness. It is to determine whether fairness had a mediating role in the relationship between self control and happiness. Participants were 275 undergraduate students. Self control, fairness, and happiness scales were used. For data analysis, correlation analysis, factor analysis, structural equation modeling analysis were conducted. The present study used structural equation modeling to examine the relation among variables. The analyses revealed that the present data best fit the research model in which self control were directly associated with happiness and mediated by fairness(${\chi}^2(51)=91.723$, TLI=0.919 CFI=0.937 RMSEA=0.054). The results indicate that self control affect happiness directly. And also self control affect happiness indirectly by mediation of fairness. Self control had a positive effect on fairness and happiness. This suggests that it is important to have educational and psycho-social interventions to improve happiness of undergraduate students.

• Journal of the Korea Convergence Society
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• v.8 no.4
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• pp.189-197
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• 2017

In the design of an automotive structural component, one of the more important tasks for a design engineer is to determine the life of the component and to ensure that the component will not fail prematurely. In order to accomplish this, a design engineer will first use simple section analysis to come up with a section shape in the concept design stage and use more advanced analysis for stress level. At this stage, the analysis should focus on understanding overall behavior in terms of load paths and gross stress levels. A model that is adequate for a stiffness analysis of the structure will usually provide an adequate level of stress information in the design process. To perform a detailed stress analysis, the structure models must have the detailed local areas such as stress concentrations or force(or displacement) distributions. This paper is to present the design considerations for the stress analysis of automotive structure.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.11 no.4
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• pp.287-295
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• 1986

In this paper, a SBC(sub-band-coding) is proposed to code a speech signal for a digital mobile radio and a robustness of speech quality of the SBC over the Rayleigh fading channel is investigated via a computer simulation. First the Rayleigh fading channel and 16-ary DPSK receiver models are presentes and verified its validitties by comparing with theoretical values. Three different measures: SNR, LPC distance measure and subjective listening test, were used to evaluate the effects due to the Rayleigh fading channel errors. From the results of computer simulation at BER=$10_{-3}$, $10_{-2}$, 5$ imes$$10_{-2}$, it was found that the speech remained quite intelligible at BER=$10_{-2}$and the link is still usuable even at BER=5$ imes$$10_{-2}$ Thus it was concluded that the SBC can be applicable to the digital mobile radio on the Rayleigh fading channel error in the range of $10_{-4}$~$10_{-2}$ without emplowing any error correction codes.

• The Journal of the Korea institute of electronic communication sciences
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• v.8 no.9
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• pp.1333-1342
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• 2013

New & renewable energy becomes a crucial subject to solve the problems inherent in the current energy resources, which results in the fast development of the new & renewable energy industry worldwide. However, not only its base is still weak but the high initial investment for technology development and certain scale of an energy market are required in many cases. For this reason, many countries in the world, including Korea, run the energy policies to foster the new & renewable energy industry such as RSP and FIT. In general, a policy should be established to take various, intertwined interests as well as a number of variables related to economic, social, environmental, and international matters into comprehensive consideration. For new & renewable energy industry, there are many variables to be considered and indexes necessary for evaluation but it is hard to take all of them into account. Even though they were considered, no criteria are available for use in a consistent manner. Therefore, this study plans to develop an evaluation model for the Korean new & renewable energy policy.

• KIPS Transactions on Computer and Communication Systems
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• v.4 no.10
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• pp.349-360
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• 2015

In recent year, phishing attacks are flooding with services based on the web technology. Phishing is affecting online security significantly day by day with the vulnerability of web pages. To prevent phishing attacks, a lot of anti-phishing techniques has been made with their own advantages and dis-advantages respectively, but the phishing attack has not been eradicated completely yet. In this paper, we have studied phishing in detail and categorize a process of phishing attack in two parts - Landing-phase, Attack-phase. In addition, we propose an phishing detection methodology based on web sites heuristic. To extract web sites features, we focus on URL and source codes of web sites. To evaluate performance of the suggested method, set up an experiment and analyze its results. Our methodology indicates the detection accuracy of 98.9% with random forest algorithm. The evaluation of proof-of-concept reveals that web site features can be used for phishing detection.