• Korean journal of communication and information
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• v.72
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• pp.52-91
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• 2015

The purpose of this study is to examine the effects of attribute agenda-setting and priming through content analysis and a survey about Particulate Matter($PM_{10}$ & $PM_{2.5}$) using both promotional news and general news. The study results were as follows. First, promotional news and general news were found to showcase similar cognitive attributes. Second, the results did not show a significant relationship between highlighted attributes in media coverage and the public's salient attributes, but media attributes had been generally reflected in the public's perception because the public was highly aware of the importance of all media attributes. Third, the recognition of the public's attribute importance affected the direction of public opinion, which resulted in the acceptance of priming effects. Meanwhile, the recognition of the public's attribute importance towards economic damage, international cooperation, individual response, and the recognition of promotional news had affected risk perception. Furthermore, the recognition of promotional news and involvement appeared to have an interaction effect on risk perception.

• The Korean Journal of Financial Management
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• v.7 no.1
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• pp.1-20
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• 1990

In most of studies on market efficiency, the stability of risk measures and the normality of residuals unexplained by the pricing model are presumed. This paper re-examines stock splits, taking the possible violation of two assumptions into accounts. The results does not change the previous studies. But, the size of excess returns during the 2-week period before announcements decreases by 43%. The results also support that betas change around announcements and the serial autocorrelation of residuals is caused by events. Based on the results, the existing excess returns are most likely explained as a compensation to old shareholders for unwanted risk increases in their portfolio, or by uses of incorrect betas in testing models. In addition, the model suggested in the paper provides a measure for the speed of adjustment of the market to the new information arrival and the intensity of information contents.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.34 no.1
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• pp.13-20
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• 1998

The moving behaviour of Yellowtail Seriola quinqueradiata schools in the main-net of a large scale set-net was investigated in relation to the catching function of the funnel-net by a scanning sonar. The investigation was took place in the Kishihata set-net fishing ground located in Nanao city Ishigawa prefecture, Japan from Nov. 9 to Nov. 13, 1992. The obtained results are summarized as follows; 1. Fish schools showed the greatest number at the playground in the morning and at the bag-net in the afternoon. The fish schools remained long time in the main-net. 2. The rate of fish school through the funnel-net was smaller than that of fish school which is though the playground and bag-net. Because the Yellowtail school changed the shape of school in passing the funnel-net. 3. The rate of entering the bag-net was 24%, among the fish school heading to the outer funnel-net. But, the rate of escaping to the playground was 27%, among the fish school heading to the inner funnel-net. It seems that the structure of the outer funnel-net was not enough to lead the fish to the bag-net. However, the structure of the inner funnel-net was very effective at preventing escape. 4. It is appropriate to haul the net in the morning in considering the number of accumulated fish in the bag-net during the survey.

• Management & Information Systems Review
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• v.38 no.2
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• pp.225-240
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• 2019

It has been known that health industry clusters promote economy of a nation in a macro view and make growth and development of individual firm. As a result, Korean health industry has been grown to play a role of making a high value added in Kwangkyo, Daedeok, Wonju, and Songdo. Using 156 firms locating in health industry clusters such as Kwangkyo, Daedeok, Wonju, and Songdo in increasing value added, this study investigated the structural relationships among R&D resources, R&D collaboration, policy support, and operational performance. All hypotheses, except a hypothesis for the effect R&D resources on operational performance, are reported to be statistically significant. In other words, the positive effect of R&D resources on policy support is reported. And policy support and R&D collaboration positively affect operational performance, and also the positive effect of policy support on R&D collaboration is reported. From the empirical results, we can know that policy support and R&D collaboration are the crucial factors to promote operational performance of the firms locating in Korean health industry clusters. It is important that this study has been investigated with the firms of health industry developing economy of a nation.

• Journal of Environmental Impact Assessment
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• v.28 no.1
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• pp.23-34
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• 2019

Global warming becomes a serious issue that poses subsidiary issues like a sea level rise or a capricious climate over the world. Because of severe heat-wave of the summer in Korea in 2016, a big attention has been focused on urban heat island since then. Not just about heat-wave itself, many researches have been concentrated on how to adapt in this trendy warming climate and weather in a small scope. A big part of existing studies is mitigating "Urban Heat Island effect" and that is because of huge impervious surface in urban area where highly populated areas do diverse activities. It is a serious problem that this thermal context has a high possibility causing mortality by heat vulnerability. However, there have been many articles of a green infrastructures' cooling impact in summer. This research pays attention to measure cooling effect of a street planting considering urban canyon and type of green infrastructures in neighborhood scale. This quantitative approach was proceeded by ENVI-met simulation with a spatial scope of a commercial block in Seoul, Korea. We found the dense double-row planting is more sensitive to change in temperature than that of the single-row. Among the double-row planting scenarios, shrubs which have narrow space between the plant and the land surface were found to store heat inside during the daytime and prevent emitting heat so as to have a higher temperature at night. The quantifying an amount of vegetated spaces' cooling effect research is expected to contribute to a study of the cost and benefit for the planting scenarios' assessment in the future.

• Tunnel and Underground Space
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• v.31 no.6
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• pp.593-609
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• 2021

We proposed a numerical method for the thermo-mechanical behavior of rock fracture using a grain-based distinct element model (GBDEM) and simulated thermally induced fracture slip. The present study is the benchmark simulation performed as part of DECOVALEX-2023 Task G, which aims to develop a numerical method to estimate the coupled thermo-hydro-mechanical processes within the crystalline rock fracture network. We represented the rock sample as an assembly of Voronoi grains and calculated the interaction of the grains (blocks) and their interfaces (contacts) using a distinct element code, 3DEC. Based on an equivalent continuum approach, the micro-parameters of grains and contacts were determined to reproduce rock as an elastic material. Then, the behavior of the fracture embedded in the rock was characterized by the contacts with Coulomb shear strength and tensile strength. In the benchmark simulation, we quantitatively examined the effects of the boundary stress and thermal stress due to heat conduction on fracture behavior, focusing on the mechanism of thermally induced fracture slip. The simulation results showed that the developed numerical model reasonably reproduced the thermal expansion and thermal stress increment, the fracture stress and displacement and the effect of boundary condition. We expect the numerical model to be enhanced by continuing collaboration and interaction with other research teams of DECOVALEX-2023 Task G and validated in further study experiments.

• (The) Research of the performance art and culture
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• no.43
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• pp.229-261
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• 2021

On the musical stage in 2019, there were many works depicting the Japanese colonial period. This is due to 2019 the timeliness of the March 1st Movement and the centennial of the establishment of the Provisional Government of the Republic of Korea. The way of remembering and commemorating historical facts reflects the power relationship between memory subjects and the time, namely the politics of memory. Until now, stage dramas dealing with the era of Japanese rule have focused on the commemoration of modern national and national defense, including feelings of misfortune and respect for patriots. This study analyzed the metaphor of the memorials emphasized to the audience in the commemorative musicals Shingheung Military School, Ku: Songs of the Goblin, and Watch which were performed in 2019, and looked at how to adjust memories and memorials. The above works highlight the narratives of ordinary people as well as those recorded against the backdrop of the Manchurian Independence Movement and Hongkou Park, expanding the object of the commemoration. Through this, active armed resistance efforts, self-reflection and reflection were highlighted. The case of Shingheung Military School revealed the earnestness of ordinary people who led the independence movement through the movement of central figures. Ku: Songs of the Goblin revises memories by reproducing forgotten objects and apologizing through time slip. Watch has strengthened the spectacles of facilities through documentary techniques such as photography, news reels, and newspaper articles, but it also reveals limitations limited to records. In the 3.1 Movement and the 100th anniversary of the establishment of the Provisional Government of the Republic of Korea, devices that actively reveal that the "people's movement" is connected to the present. To this end, the official records reflected the newly produced values and memories and devoted themselves to the daily lives and emotions of the crowd. In addition, both empirical consideration and calligraphy were utilized to increase reliability. These attempts are meaningful in that they have achieved the achievement of forming contemporary empathy.

• Journal of the Korean Chemical Society
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• v.48 no.1
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• pp.77-84
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• 2004

The purpose of this study was to analyze the controversial points in the concepts of materials in the science textbook of middle school and to provide alternatives of teaching method. For this study, units in connected textbooks were analyzed and the teaching method using ball-and-stick models was developed. The subjects were 130 second graders from a middle school in Seoul, Korea. It aimed to compare the effectiveness of using ball-and-stick models for lesson with the one of traditional lessons, in learning concepts concerning materials by cognitive levels and to investigate the difference of scientific concept formation about concepts concerning materials by their cognitive levels between experimental group and control group by using concept formation questionnaires. Before the instructions, a short-version GALT was administered. After instructions, the posttest of concepts and attitude test connected with science subject were administered, and 10 months later, the posttest of concepts was administered to analyze the long-term memory effects. According to the results, the experimental group using the ball-and-stick models had significantly higher scores at conceptual understanding and long-term memory effects than the control group and improved the attitude relevant to science subject, and also had affirmative effects in attitude for science and science work. When analyzing the results according to the cognitive level, the long-term memory effects was high in the concrete operational stage students. From the results of this study, middle school students that are more concrete operational stage and transitional stage than formal operational stage elevates interesting in studying by using ball-and-stick models and making material form concretely. It would be effective in helping the students develope the correct concepts by connecting real world as materials and the particle world as atom.

• Journal of The Korean Association For Science Education
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• v.34 no.5
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• pp.437-447
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• 2014

Learning progressions (LP), which describe how students may develop more sophisticated understanding over a defined period of time, can inform the design of instructional materials and assessment by providing a coherent, systematic measure of what can be regarded as "level appropriate." We developed LPs for the nature of matter for grades K-16. In order to empirically test Korean students, we revised one of the constructs and associated assessment items based on Korean National Science Standards. The assessment was administered to 124 Korean secondary students to measure their knowledge and submicroscopic representations, and to assign them to a level of learning progression for the particle nature of matter. We characterized the level of students' understanding and models of the particle nature of matter, and described how students interpret various representations of atoms and molecules to explain scientific phenomena. The results revealed that students have difficulties in understanding the relationship between the macroscopic and molecular levels of phenomena, even in high school science. Their difficulties may be attributed to a limited understanding of scientific modeling, a lack of understanding of the models used to represent the particle nature of matter, or limited understanding of the structure of matter. This work will inform assessment and curriculum materials development related to the fundamental relationship between macroscopic, observed phenomena and the behavior of atoms and molecules, and can be used to create individualized learning environments. In addition, the results contribute to scientific research literature on learning progressions on the nature of matter.

• Journal of Astronomy and Space Sciences
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• v.14 no.1
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• pp.94-108
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• 1997

The temperature of the upper thermosphere is generally varied with the solar activity, and largely with geomagnetic activity in the high latitude. The data analyzed in this study are acquired at two ground stations, Thule Air Base($76,5{deg} N, 68.4{deg} W, A = 86{deg}$) and $S{psi}ndre Str{psi}mfjord (67.0{deg} N, 50.9{deg} W, A = 74{deg}$), Greenland. Both stations are located in the high latitude not only geographically but also geomagnetically. The terrestrial night glow at 6300 ${angs}$ from atomic oxygen has been observed from the two ground-based Fabry-Perot interferometers, during periods of 1986~1991 in Thule Air Base and 1986~1994 in $S{psi}ndre Str{psi}mfjord$. Some features noted in this study are as follows: (1) The correlation between the solar activity and the measured thermospheric temperature is highest in the case of $3{leq}Kp{leq}4$ in Thule, and increases with the geomagnetic activity in $S{psi}ndre Str{psi}mfjord$. (2) The measured temperatures at Thule is generally higher than those at $S{psi}ndre Str{psi}mfjord$, but the latter shows steeper slope with the solar activity. (3) The harmonic analysis shows that the diurnal variation(24hrs) is the main feature of the daily temperature variation with a temperature peak at about 13-14 LT (LT=UT-4). However, the semi-diurnal variation is evident during the period of weak solar activity. (4) Generally the predicted temperatures from both MSIS86 and VSH models are lower than the measured temperature, and this discrepancy grows as the solar activity increases. Therefore, we urge modelers to develope a new thermospheric model utilizing broader sets of measurements, especially for high solar activity.