• Journal of the Korean Operations Research and Management Science Society
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• v.39 no.4
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• pp.33-49
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• 2014

This study empirically examines the impact of firms' environmental (E), social (S), and governancial (G) factors on their short-term and long-term values. To measure firms' non-financial performance, we use ESG performance grades published by KCGS (Korea Corporate Governance Service). We employ stock log return as the proxy of each firm's short-term value, and Tobin's Q ratio as that of its long-term value. From a series of regression analyses, we find each of the ESG factors generally has a negative impact on stock return while it has a positive impact on the Tobin's Q ratio. These results imply that firms' effort for enhancing their non-financial performance may adversely affect their financial performance in a short term; but in the long-term point of view, firms' values increase through their good images engraved by their respective social, environmental and governancial efforts. In addition, we compare the relative strength of impact among E, S, G, the three non-financial factors on the firms' value measured in Tobin's Q ratio, and find that S (social factor) and G (governancial factor) give statistically significant impact on the firms' value respectively. This result tells us it would be advised to strategically embed CSV (creating shared value) pursuing both of profits and social responsibility in the firms' future agenda. While E (environmental factor) is shown to be an insignificant factor for the firms' value, it should be emphasized as a major concern by all the stakeholders in order to form a sound business ecosystem.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.20 no.2
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• pp.450-460
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• 1996

To investigate the effect of stress wave propagation for crack tip, impact responses of two-dimensional plates with oblique cracks are investigated by a numerical method. In the numerical analysis, the finite element method is used in space domain discretization and the Newmark constant acceleration algorithm is used in time integration. According to the numerical results from the impact response analysis. it is found that the stress fields are bisected at the crack surface and the parts of stress intensity are moved along the crack face. The crack tip stress fields are yaried rapidly. The magnitude of crack tip stress fields are converted to dynamic stress intensity factor. Dynamic sress intensity factor appears when the stress wave has reached at the crack tip and the aspect of change of dynamic stress intensity factor is shown to be the same as the part of the flow of stress intensity.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.19 no.12
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• pp.1306-1314
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• 2009

By rising the interests of the railroad, It has been required the research about railroad structure. And since 2000, the study about railway bridges caused by steel box railway bridges has been only 0.2 %. So I was hard to find out about steel box railway bridges. In this study, I evaluate and analyze 4 types(KTX, Saemaeul, Mugunghwa, Freight) of dynamic caused by train loading, natural frequency and damping ratio, verticality deflection and verticality acceleration, end slope deflection, impact factor for dynamic characteristics analysis. natural frequency was measured 2.45 Hz~3.34 Hz and damping ratio revealed for 1.26~2.84 %. Maximum verticality deflection(4.86 mm) was sufficiently satisfied the design criteria(30.1 mm), but in the case of verticality acceleration's respond, design criteria BRDM(bridge design manual) & CTRL presentation derive rail limit value 0.35 g be more than value 6 time recorded, maximum was measured 0.49 g in 3 kinds of train(KTX, Saemaeul, Mugunghwa), except for Freight. Survey impact factor of Experiment bridge was 0.20 which is measured when the KTX(15:04) was driving. impact factor is enough contended with design criteria 0.29 which is presented in domestic railway design criteria and thoroughly guarantee the dynamic stability.

• Journal of the Korean Society of Costume
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• v.51 no.3
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• pp.51-58
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• 2001

The purpose of this study was to investigate the effects of store image preferences on clothing impulse purchasing of male college students. The sample included 290 male college students, and an instrument was developed based on the previous studies. The statistical analyses used for this study were factor analysis and multiple regression. The result of factor analysis showed that store image preferences consisted of five factors : promotion, display, service, product, brand preferences. Clothing impulse purchasing consisted of product-driven impulse purchasing, situation-driven impulse purchasing, emotion-driven impulse purchasing. Multiple regression revealed that there were significant effects of store image preferences on dimensions of clothing impulse purchasing. For example, promotion preference factor had a positive impact on product-driven impulse purchasing and situation-driven impulse purchasing, but had a negative impact on emotion-driven impulse purchasing. The relative importance of store image preference factors were different according to different dimensions of clothing impulse purchasing.

• Journal of Digital Convergence
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• v.7 no.2
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• pp.71-81
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• 2009

This paper studied the impact of Internet addiction on school life adaptation of high school students. We searched the literature on Internet addiction for such research and analyzed the impact that Internet addiction has on school life fitness. The SPSS statistics program was used for Internet addiction factor analysis and the analysis was carried out through the structure equation model. The family relation, individual relation, school relation and friend relation factor were deduced to Internet addiction as a result. It was revealed that the individual relation factor among Internet addiction factors had an influence on school life fitness. It is expected that this research will prove helpful in providing preventative education for Internet addiction

• Journal of the Korean Society for Railway
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• v.9 no.6 s.37
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• pp.784-791
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• 2006

This paper presents the test results to evaluate the healthiness of the ballast in subway. The test includes the dynamic load test in servicing Line the screen classification test of aggregates and the wear test. From the results, the aspect and the property of the ballast are evaluated. The dynamic load tests explain the relationship between the deterioration of the ballast and the fluctuation of loads. The assessment of impact factor based on the field test results in a good property of test blocks is proposed.

• Structural Engineering and Mechanics
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• v.15 no.1
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• pp.21-38
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• 2003

The formulation of a new bridge-vehicle system using shell with eccentric beam elements has been introduced in a companion paper (Part I). The new system takes into account of the contribution of the twisting and pitching modes of vehicles to the bridge responses. It can also be used to study the dynamic transverse load distribution of a bridge. This paper presents a parametric study on the impact induced by one vehicle or multi-vehicle running across a bridge using the proposed model. Several parameters were considered as variables including the mass ratio, the speed parameter, the frequency ratio and the axle spacing parameter to investigate their effects on the impact factor. A total number of 189 cases were carried out in this parametric study. Within the realistic range of vehicle considered, the maximum impact factors could be 2.24, 1.78 and 1.49 for bridges with spans 10 m, 20 m and 30 m respectively.

• Nuclear Engineering and Technology
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• v.42 no.4
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• pp.394-413
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• 2010

The object of this paper is to identify the key elements that impact a radiation dose at EAB (Exclusion Area Boundary). This study is based on the AST (Alternative Source Terms) as defined in Regulatory Guide 1.183. The LOCA (Loss of Coolant Accident) and the LRA (Locked Rotor Accident) are selected as limiting cases. A sensitivity analysis of accidental behavior with respect to various parameters during LOCA and LRA at Kori Unit 1 is also undertaken for the following objectives: to determine the limiting parameters, to find the impact trend of the radiation dose, and to find the safety margin between AST and TID (Technical Information Document) methodologies. This work confirms that key parameters are particulate removal rate, decontamination factor, iodine chemical form, gap fraction, partitioning factor, and the impact of isotopes group. Comparing TID with AST, the radiation dose of TID is about 80% greater than that of AST under a LOCA, and about 60% greater than that of AST for the case of a LRA; thus the safety margin is remarkably increased when the AST is used. In this work, the sensitivity analysis results are presented in terms of a sensitivity index called the "NDD (Normalized Dose Difference)", which compares the impact of parameters with that of a reference case. These values are derived by using a combination of the leak rate (primary to secondary), iodine chemical form, gap fraction, partitioning factor, spray removal rate, source term, and other variables.

• Coupled systems mechanics
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• v.11 no.4
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• pp.285-295
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• 2022

Laminated composite plates are utilized extensively in different fields of construction and industry thanks to their advantages such as high stiffness-to-weight ratio. Additionally, they are characterized by their directional properties that permit the designer to optimize their stiffness for specific applications. This paper presents a numerical analysis and optimization study of plates made of composite subjected to low velocity impact. The main aim is to identify the optimum fiber orientations of the composite plates that resist low velocity impact load. First, a three-dimensional finite element model is built using LS DYNA computer software package to perform the impact analyses. The composite plate has been modeled using solid elements. The failure criteria of Tsai-Wu's criterion have been used to control the strength of the composite material. A good agreement has been found between the predicted numerical results and experimental results in the literature which validate the finite element model. Then, an Adaptive Simulated Annealing (ASA) has been used to optimize the response of impacted composite laminate where its objective is to maximize the safety factor by varying the ply angles. The results show that the ASA is robust in the sense that it is capable of predicting the best optimal designs.

• Journal of Information Science Theory and Practice
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• v.3 no.2
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• pp.42-57
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• 2015

Purpose. : The present study is an attempt to find out the impact of self-citations on Impact Factor (IF) across disciplines. The study examines the number of research articles published across 27 major subject fields covered by SCImago, encompassing as many as 310 sub-disciplines. The study evaluates aspects like percentage of self-citations across each discipline, leading self-citing countries and continents, and the impact of self-citation on their IF. Scope. : The study is global in nature, as it evaluates the trend of self-citation and its impact on IF of all the major subject disciplines of the world, along with countries and continents. IF has been calculated for the year 2012 by analyzing the articles published during the years 2010 and 2011. Methodology/Approach. : The study is empirical in nature; as such, statistical and mathematical tools and techniques have been employed to work out the distribution across disciplines. The evaluation has been purely under-taken on the secondary data, retrieved from SCImago Journal and Country Ranking. Findings. : Self-citations play a very significant part in inflating IF. All the subject fields under study are influenced by the practice of self-citation, ranging from 33.14% to 52.38%. Compared to the social sciences and the humanities, subject fields falling under the purview of pure and applied sciences have a higher number of self-citations, but a far lesser percentage than the social sciences and humanities. Upon excluding self-citations, a substantial amount of change was observed in the IF of subject fields under study, as 18 (66.66%) out of 27 subjects fields faced shuffle in their rankings. Variation in rankings based on IF with and without self-citation was observed at subject level, country level, and continental level.