• Korean Journal of Forensic Psychology
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• v.11 no.1
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• pp.63-87
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• 2020

Judgment and decision-making studies have shown that people are easily influenced and biased by information irrelevant to the object of judgment. There is a great deal of research that indicates that bias exists in the legal judgment scene. One of them is a bias induced by defendants' character evidence. This study examined whether cognitive activities such as discussion, counterfactual thinking, and peer assessment could reduce the bias induced by the character evidece. In Experiment 1, 121 college students were asked to give the percentage they believed the defendant to be guilty. There was no cognitive activity for the control group. There were three different cognitive activities for the experimental group: discussion, counterfactual thinking and discussion, and counterfactual thinking and peer assessment. Results showed reduction in bias for all the experimental groups, and there was no difference between them. In Experiment 2, there were 125 participants from general population for the same procedure as in Experiment 1. Results showed reduction in bias only for the counterfactual thinking and discussion group. In general discussion, we speculated the implication of the results and the reason for the difference between the two experiments.

• Structural Engineering and Mechanics
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• v.81 no.2
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• pp.179-194
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• 2022

The bending, buckling and free vibration responses of functionally graded material (FGM) beams are investigated semi-analytically by the scaled boundary finite element method (SBFEM) in this paper. In the concepts of the SBFEM, the dimension of computational domain can be reduced by one, therefore only the axial dimension of the beam is discretized using the higher order spectral element, which reduces the amount of calculation and greatly improves the calculation efficiency. The governing equation of FGM beams is derived in detail by the means of the principle of virtual work. Compared with the higher-order beam theory, fewer parameters and simpler control equations are used. And the governing equation is transformed into a first-order ordinary differential equation by introducing intermediate variables. Analytical solutions of the governing equation can be obtained by pade series expansion in the direction of thickness. Numerical example are compared with the numerical solutions provided by the previous researchers to verify the accuracy and applicability of the proposed method. The results show that the proposed formulations can quickly converge to the reference solutions by increasing the order of higher order spectral elements, and high accuracy can be achieved by using a small number of the elements. In addition, the influence of the structural sizes, material properties and boundary conditions on the mechanical behaviors of FG beams subjected to different load types is discussed.

• Korean Journal of Social Welfare Studies
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• v.40 no.1
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• pp.139-161
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• 2009

The purpose of this study was to investigate the paths of the related variables that exert an influence upon the increase in mild and serious delinquencies of part-time work adolescents. Based on differential association theory, social control theory and power resource theory, the research model was composed and analyzed through structural equation model. Data came from survey which was done by fifteen high schools located in Seoul, and 201 questionnaire of returned were used for analysis. The results were congruent with theoretical expectations. The relationship between work hour per week and delinquency was mediated by delinquent propensity of fellow workers, amount of spending money and school adjustment. In conclusion, various theoretical and practical implications for social work practice focusing on the part time work students were discussed. Enforcement of regulation and revision of current law and various ways for helping and supervising working students in school, family and working places are needed.

• Steel and Composite Structures
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• v.44 no.4
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• pp.503-517
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• 2022

This paper presents the mechanical buckling of bi-directional functionally graded sandwich beams (BFGSW) with various boundary conditions employing a quasi-3D beam theory, including an integral term in the displacement field, which reduces the number of unknowns and governing equations. The beams are composed of three layers. The core is made from two constituents and varies across the thickness; however, the covering layers of the beams are made of bidirectional functionally graded material (BFGSW) and vary smoothly along the beam length and thickness directions. The power gradation model is considered to estimate the variation of material properties. The used formulation reflects the transverse shear effect and uses only three variables without including the correction factor used in the first shear deformation theory (FSDT) proposed by Timoshenko. The principle of virtual forces is used to obtain stability equations. Moreover, the impacts of the control of the power-law index, layer thickness ratio, length-to-depth ratio, and boundary conditions on buckling response are demonstrated. Our contribution in the present work is applying an analytical solution to investigate the stability behavior of bidirectional FG sandwich beams under various boundary conditions.

• Journal of The Geomorphological Association of Korea
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• v.27 no.2
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• pp.65-80
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• 2020

This paper deals with risk assessment of life in a landslide-prone area by a GIS-based modeling method. Landslide susceptibility maps can provide a probability of landslide prone areas to mitigate or proper control this problems and to take any development plan and disaster management. A landslide inventory map of the study area was prepared based on past historical information and aerial photography analysis. A total of 550 landslides have been counted at the whole study area. The extracted landslides were randomly selected and divided into two different groups, 50% of the landslides were used for model calibration and the other were used for validation purpose. Eleven causative factors (continuous and thematic) such as slope, aspect, curvature, topographic wetness index, elevation, forest type, forest crown density, geology, land-use, soil drainage, and soil texture were used in hazard analysis. The correlation between landslides and these factors, pixels were divided into several classes and frequency ratio was also extracted. Eventually, a landslide susceptibility map was constructed using a logistic regression model based on entire events. Moreover, the landslide susceptibility map was plotted with a receiver operating characteristic (ROC) curve and calculated the area under the curve (AUC) and tried to extract a success rate curve. Based on the results, logistic regression produced an 85.18% accuracy, so we believed that the model was reliable and acceptable for the landslide susceptibility analysis on the study area. In addition, for risk assessment, vulnerability scale were added for social thematic data layer. The study area predictive landslide affected pixels 2,000 and 5,000 were also calculated for making a probability table. In final calculation, the 2,000 predictive landslide affected pixels were assumed to run. The total population causalities were estimated as 7.75 person that was relatively close to the actual number published in Korean Annual Disaster Report, 2006.

• Journal of the Society of Disaster Information
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• v.20 no.2
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• pp.379-389
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• 2024

Purpose and Method: Crowed Events can lead to sudden accidents caused by unpredictable variables. Therefore, focusing on the '10.29 Itaewon accident' among the representative cases, we examined the accident as the process of occurrence. In addition, improvement measures were suggested through analysis of related legal systems. Result: In the Itaewon accident, a "colony wave phenomenon" occurred due to "ultra-high-density cluster stay". In addition, cluster destruction occurred from a weak location in the cluster due to clusters and pressures in different directions to avoid this. Looking at the laws related to the safety management of Crowed Events, the laws and regulations differ depending on the location and type. Due to the complementary nature of the approach to the legal blind spot, the legal system that uses similar terms of the same concept and is not systematic is causing uncertainty in the application and interpretation of the law. Conclusion: Crowd control and on-site management should be carried out for events when the cluster density is expected to reach 8 people/m² or reached. Consistency should be maintained through the unified application of legislation to related legislation.

• Wind and Structures
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• v.38 no.2
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• pp.129-146
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• 2024

Aiming at the problem of non-stationary wind field simulation of downbursts, a non-stationary down-burst generation system was designed by adding a nozzle and program control valve to the inlet of the original wall jet model. The computational fluid dynamics (CFD) method was used to simulate the downburst. Firstly, the two-dimensional (2D) model was used to study the outflow situation, and the database of working conditions was formed. Then the combined superposition of working conditions was carried out to simulate the full-scale measured downburst. The three-dimensional (3D) large eddy simulation (LES) was used for further verification based on this superposition condition. Finally, the wind tunnel test is used to further verify. The results show that after the valve is opened, the wind ve-locity at low altitude increases rapidly, then stays stable, and the wind velocity at each point fluctuates. The velocity of the 2D model matches the wind velocity trend of the measured downburst well. The 3D model matches the measured downburst flow in terms of wind velocity and pulsation characteris-tics. The time-varying mean wind velocity of the wind tunnel test is in better agreement with the meas-ured time-varying mean wind velocity of the downburst. The power spectrum of fluctuating wind ve-locity at different vertical heights for the test condition also agrees well with the von Karman spectrum, and conforms to the "-5/3" law. The vertical profile of the maximum time-varying average wind veloci-ty obtained from the test shows the basic characteristics of the typical wind profile of the downburst. The effectiveness of the downburst generation system is verified.

• The Journal of the Convergence on Culture Technology
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• v.10 no.2
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• pp.525-530
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• 2024

The need for an environmental monitoring system that obtains and provides environmental information in real time is increasing. In particular, in the case of water quality management in public waters, regular management must be conducted through manual and automatic measurement by law, and air pollution also requires regular measurement and management to reduce fine dust and exhaust gas in connection with the realization of carbon neutrality. In this study, we implemented a system that can measure and monitor water pollution and air pollution information in real time. A hovercraft capable of moving on land and water simultaneously was used as a measurement tool. Water quality measurement and air pollution measurement sensors were installed on the hovercraft body, and a communication module was installed to transmit the information to the monitoring system in real time. The structure of a hovercraft for environmental measurement was designed, and a LoRa module capable of low-power, long-distance communication was applied as a real-time information transmission communication module. The operational performance of the proposed system was confirmed through actual hardware implementation.

• Journal of The Korean Association For Science Education
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• v.18 no.1
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• pp.93-108
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• 1998

This study investigated science textbooks used from 1906 to 1915 in Korea, which is often neglected in previous researches. By doing so, more practical and specific understanding of the science education during that period can be made. It was based on the historical achieves "School Textbook List"(Vol. $4{\sim}9$) which was published by the Ministry of Education and the Government General of Chosen and other sources. The results and conclusions of the research are as follow; (1) The science textbooks which have been used from 1906 to 1915 in Korea can be categorized into three different tapes of books, either written in Chinese, or in Japanese, or in Korean. The names of science textbooks were Nature Study, Physics, Chemistry, Natural History, Hygienics, Physiology, Zoology, Botany, Astronomy, Physiography, Mineralogy, Geology. These names were much broader than those in curriculum settled by the government and rather correspond to the names of science textbooks in curriculum which settled by private schools. Therefore those science textbooks had been mainly used in private schools. Moreover almost all of the science textbooks published in Korea have started to appear after 1906. Since then many schools were newly opened and the number of students increased. It is possible to say that substantial science education in Korea established after 1906. (2) Science textbooks from 1906 to 1915 printed in Korea were controlled in their use by the Ministry of Education and the Government General of Chosen. They were the main means of government regulations, supported by Private School Ordinance, Regulations for Official Examination of textbooks in 1908 and Law of Publication in 1909. According to the result of official examination, as the time went by under the Japanese ruling of Korea, the increasing number of science textbooks were getting banned. While the science textbooks had enjoyed more freedom than the other textbooks from the control by inspection of the Government General of Chosen, the situation has been significantly changed as Japan started to intensity the control of all kinds of textbooks in Korea. Although there were a lot of copied science textbooks, 62 science textbooks printed in Korea, 72 Japanese science textbooks were used in Korea, and 40 Korean were to be engaged in science education compiling and copying science textbooks. There developments in science textbooks alone suggest that there were enormous amount of potentials in Korean science education at that time. However, all of these effects and progresses were destroyed when the sovereign authority of Korea was lost to Japan in 1910.

• Korean Security Journal
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• no.52
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• pp.73-91
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• 2017

This study is based on the political and economic standpoint of each country, Use advanced equipment to prevent new terrorism from causing widespread damage, In order to establish a countermeasures against terrorism in accordance with the reality of Korea, which is effective in responding to terrorist attacks, Korea conducted a SWOT analysis of the terrorist environment and terrorist environment through specialists. First, internal strengths of Korea 's terrorist environment include stable security situation, weakness of religious and ethnic conflicts, strong regulation and control of firearms, and counter terrorism capabilities and know - how accumulated during major international events. Second, the internal weaknesses of the terrorist environment in Korea include the insecurity of the people, the instability caused by the military confrontation with North Korea, the absence of anti-terrorism law system, the difficulty of terrorism control and management by the development of the Internet and IT technology. Third, the external opportunities for Korea 's terrorist environment are as follows: ease of supplementation and learning through cases of foreign terrorism failure, ease of increase of terrorist budget and support with higher terrorism issues, strengthening of counterterrorism through military cooperation with allied nationsRespectively. Fourth, the external threats to the terrorist environment in Korea are the increase of social dissatisfaction due to the continuous influx of defectors and foreign workers, the goal of terrorism from international terrorist organizations through alliance with the United States,Increased frequency of incidents, and increased IS coverage of terrorism around the world. In addition, the SWOT in - depth interviews on the terrorist environment of the expert group were conducted to diagnose and analyze the problems, terrorism awareness and legal system in the Korean terror environment. The results of the study are summarized as follows.First, the basic law on terrorism should be enacted.Second, the establishment of an integrated anti-terrorism organization.Third, securing and nurturing specialized personnel in response to terrorism.