• Geomechanics and Engineering
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• v.9 no.6
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• pp.729-742
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• 2015

The aim of the present work was the study of instability in a loose sand from Les Dunes beach in Ain Beninan, Algeria, where the Boumerdes earthquake occurred in 2003. This earthquake caused significant structural damages and claimed the lives of many people. Damages caused to infrastructures were strongly related to phenomena of liquefaction. The study was based on the results of two drained and six undrained triaxial tests over a local sand collected in a region where liquefaction occurred. All the tests hereby analyzed followed compression stress-paths in monotonic conditions and the specimens were isotropically consolidated, since the objective was to study the instability due to static loading as part of a more general project, which also included cyclic studies. The instability was modeled with the second-order work increment criterion. The definition of the instability line for Les Dunes sand and its relation with yield surfaces allowed the identification of the region of potential instability and helped in the evaluation of the susceptibility of soils to liquefy under undrained conditions and its modeling. The dilatancy rate was studied in the points where instability began. Some mixed tests were also simulated, starting with drained conditions and then changing to undrained conditions at different time steps.

• Proceedings of the KSR Conference
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• 2008.11b
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• pp.169-178
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• 2008

In this paper, it is shown that Carson's equation can still be applied for the calculation of the series reactance of transmission lines with no ground return current as well as the one with ground return. It is proved in the following method. First two voltage drop equations for three-phase three wire transmission line are derived, one without considering ground return and the other using Carson's equation. The impedance matrix of the two equations are different from each other. But if we put the condition of zero ground current, $I_a+I_b+I_c=0$, those two equations becomes the identical equations. Therefore even a transmission line is not grounded, its line parameters can still be obtained using the Carson's equation. It has been confused whether or not Carson's equation can be used for an ungrounded system. It is because where ever Carson's equation is shown in the book, it also says that the system has ground return current paths as a premise. It is also verified with EMTP studies on the test circuit.

• Journal of Korea Trade
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• v.23 no.4
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• pp.131-148
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• 2019

Purpose - Based on the Korea-China FTA as the starting point, this paper makes an empirical analysis of the main influencing factors of the FTA utilization and performance of SMEs. Design/methodology - Taking into account the relationship between the internal and external environmental factors on FTA activities and performance of Korea's SMEs, with PLS-SEM and data obtained by the questionnaire, Smart PLS was applied for the analysis. Findings - The recognition of FTA in SMEs has a significant positive effect on FTA utilization and performance, the international marketing orientation factor only has a significant positive effect on the performance, while the inadequate improvement of non-tariff barriers has a significant negative impact on FTA utilization. In addition, FTA activity has a significant mediation effect on two paths. Originality/value - This paper is of great practical relevance as a tool to enable SMEs to make effective utilization of Korea-China FTA and improve their imports and exports. The paper helps grasp the main factors affecting the utilization and performance of FTA for SMEs, also to establish FTA Business Model and FTA utilization plans for specific industries in the future regarding tariff and non-tariffs compatibility.

• Journal of Auto-vehicle Safety Association
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• v.10 no.4
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• pp.40-49
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• 2018

Currently, a lot of researches about high risk test scenarios for autonomous vehicle and advanced driver assistance systems have been carried out to evaluate driving safety. This study proposes new type of test scenario that evaluate the driving safety for autonomous vehicle by reconstructing accident database of national automotive sampling system crashworthiness data system (NASS-CDS). NASS-CDS has a lot of detailed accident data in real fields, but there is no data of accurate velocity in accident moments. So in order to propose scenario generation method from accident database, we try to reconstruct accident moment from accident sketch diagram. At the same step, we propose an accident of occurrence frequency which is based on accident codes and road shapes. The reconstruction paths from accident database are integrated into evaluation of simulation environment. Our proposed methods and processor are applied to MILS (Model In the Loop Simulation) and VILS (Vehicle In the Loop Simulation) test environments. In this paper, a reasonable method of accident reconstruction typology for autonomous vehicle evaluation of feasibility is proposed.

• Transactions of the Korean hydrogen and new energy society
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• v.29 no.6
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• pp.668-679
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• 2018

Experimental and numerical data were compared through a counterflow burner for the characteristic of basic flame about SNG- C11. In order to use the numerical mechanism accurately, the validation was carried out at strain rate ($a_g=30$, $120s^{-1}$) and the UCSD model showed satisfactory results. The effective Lewis number of the extinction boundary, and the behavior of extinction for the symmetric flames of the SNG-C11, could be explained through the trend of $Le_V$, and the flame of the extinction condition was inspected by the major species, key radicals and the chemical reaction paths. The interactions phenomenon in the merged flames has chemical reaction path for producing $HO_2$ were generated at stagnation point. It can be expected the one of major factors in interaction phenomenon.

• Journal of Fashion Business
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• v.22 no.6
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• pp.25-38
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• 2018

Recently, issues on the environment, which have become key bottlenecks relative to sustainable economic development, have generated common concern. However, relatively scant research has been devoted to consideration of relations between consumers' environmental concern, green fashion advertisement value, and green consumption. In this study, using structural equation modeling (SEM), effects of environmental concern, perceived green fashion advertisement value, and attitude towards green fashion advertisements, on ecological purchases and their interrelationships are investigated. A model is constructed to link aforementioned constructs. Data, was collected through a questionnaire-based online survey (www.sojump.com) of 260 Korean consumers and 260 Chinese consumers. Findings suggest that environmental concern can improve their perception of green advertisement value. One of the findings showed strong positive relationship among green advertisement value, positive attitude, and purchase intention towards green fashion advertisement, while environmental concern negatively influenced their attitude towards green fashion advertisements. It suggests that if companies adopt green advertising strategies, environmentally-conscious consumers are willing to pay more, to purchase green fashion goods in to satisfy their needs. We should put more effort in educating consumers about environmental issues, to raise the level of environmental awareness and satisfy their concerns relative to green fashion goods. Conversely, there is significant positive relationship with the moderating effect of consumers' nationality in all paths, so results above would make significant contributions to green literature, and would also contribute to advertisement strategy implications as well. Especially fashion marketers, an use accurate and fair environmental claims in their advertisements to increase sale and profits.

• Journal of Auto-vehicle Safety Association
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• v.11 no.3
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• pp.30-36
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• 2019

This paper suggests a car-following algorithm for urban environment, with multiple target candidates. Until now, advanced driver assistant systems (ADASs) and self-driving technologies have been researched to cope with diverse possible scenarios. Among them, car-following driving has been formed the groundwork of autonomous vehicle for its integrity and flexibility to other modes such as smart cruise system (SCC) and platooning. Although the field has a rich history, most researches has been focused on the shape of target trajectory, such as the order of interpolated polynomial, in simple single-lane situation. However, to introduce the car-following mode in urban environment, realistic situation should be reflected: multi-lane road, target's unstable driving tendency, obstacles. Therefore, the suggested car-following system includes both in-lane preceding vehicle and other factors such as side-lane targets. The algorithm is comprised of three parts: path candidate generation and optimal trajectory selection. In the first part, initial guesses of desired paths are calculated as polynomial function connecting host vehicle's state and vicinal vehicle's predicted future states. In the second part, final target trajectory is selected using quadratic cost function reflecting safeness, control input efficiency, and initial objective such as velocity. Finally, adjusted path and control input are calculated using model predictive control (MPC). The suggested algorithm's performance is verified using off-line simulation using Matlab; the results shows reasonable car-following motion planning.

• Nuclear Engineering and Technology
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• v.51 no.1
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• pp.138-145
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• 2019

With the application of digital technology to safety-critical infrastructures, cyber-attacks have emerged as one of the new dangerous threats. In safety-critical infrastructures such as a nuclear power plant (NPP), a cyber-attack could have serious consequences by initiating dangerous events or rendering important safety systems unavailable. Since a cyber-attack is conducted intentionally, numerous possible cases should be considered for developing a cyber security system, such as the attack paths, methods, and potential target systems. Therefore, prior to developing a risk-informed cyber security strategy, the importance of cyber-attacks and significant critical digital assets (CDAs) should be analyzed. In this work, an importance analysis method for cyber-attacks on an NPP was proposed using the probabilistic safety assessment (PSA) method. To develop an importance analysis framework for cyber-attacks, possible cyber-attacks were identified with failure modes, and a PSA model for cyber-attacks was developed. For case studies, the quantitative evaluations of cyber-attack scenarios were performed using the proposed method. By using quantitative importance of cyber-attacks and identifying significant CDAs that must be defended against cyber-attacks, it is possible to develop an efficient and reliable defense strategy against cyber-attacks on NPPs.

• Korea Trade Review
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• v.44 no.3
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• pp.203-226
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• 2019

This study incorporates the structural relationships between leadership styles (LS), affect climate (AC), and organizational performance (OP) in Korean export manufacturing companies with three or more overseas subsidiaries. A theoretical model is suggested with the following empirical results. First, the positive effect of engaging leadership (EL) on organizational citizenship behavior (OCB), as well as of engaging leadership, involving leadership (IL), and goal-oriented leadership (GL) on team performance (TP), proved to be significant. Second, both engaging leadership and goal-oriented leadership have significant positive effects on optimism, while involving leadership has significant negative effects on pessimism. Third, only optimism has a positive (+) effect on OCB and TP. The mediating effects were proved to be significant in two paths: one in EL->optimism->OCB and the other in EL->optimism->TP. Finally, in responding to rapid changes in the external environment of exporting companies, the engaging leadership is a key source of organizational performance by forming a favorable affect climate. Therefore, top management should recognize the role of team leaders and strengthen their leadership training. In addition, it was confirmed that leaders with emotional intelligence that can respond to the affects of members play a more important role in forming an optimistic climate in Korea export manufacturing enterprises with foreign subsidiaries.

• Journal of Family Relations
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• v.22 no.2
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• pp.51-69
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• 2017

Objectives: The purpose of this study was to examine the associations and paths among parenting behaviors, cyber delinquency, and moral sensitivity in adolescents to reduce and prevent cyber delinquency. Method: The data was collected by a survey for 270 students from a middle school and a high school in G city. The valid 262 cases were analyzed by frequency, descriptive analysis with SPSS 18.0 and tested by structural equation model by using AMOS 18.0 program. Results: Results showed that 1) 'control' among the parenting behaviors has positive effects on the cyber delinquency in adolescents, 2) 'intimacy and rationality' among the parenting behaviors has positive impacts on the moral sensitivity, 3) it shows that moral sensitivity has negative effects on the cyber delinquency in adolescents, and 4) bootstrapping test for indirect effect of moral sensitivity was verified significantly. We founded the full mediation of moral sensitivity and the path of 'intimacy and rationality' to cyber delinquency through moral sensitivity. Conclusions: The results implied 1) provision of the parent education and program for parents and newlyweds to learn positive parenting behaviors and 2) application of moral education to develop moral sensitivity of adolescents in schools and communities.