• Journal of Astronomy and Space Sciences
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• v.26 no.2
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• pp.171-186
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• 2009

Various Earth-Moon transfer trajectories are designed and analyzed to prepare the future Korea's Lunar missions. Minimum fuel trajectory solutions are obtained for the departure year of 2017, 2020, 2022, and every required mission phases are analyzed from Earth departure to the final lunar mission orbit. N-body equations of motion are formulated which include the gravitational effect of the Sun, Earth and Moon. In addition, accelerations due to geopotential harmonics, Lunar J2 and solar radiation pressures are considered. Impulsive high thrust is assumed as the main thrusting method of spacecraft with launcher capability of KSLV-2 which is planned to be developed. For the method of injecting a spacecraft into a trans Lunar trajectory, both direct shooting from circular parking orbit and shooting from the multiple elliptical intermediate orbits are adapted, and their design results are compared and analyzed. In addition, spacecraft's visibility from Deajeon ground station are constrained to see how they affect the magnitude of TLI(Trans Lunar Injection) maneuver. The results presented in this paper includes launch opportunities, required optimal maneuver characteristics for each mission phase as well as the trajectory characteristics and numerous related parameters. It is confirmed that the final mass of Korean lunar explorer strongly depends onto the initial parking orbit's altitude and launcher's capability, rather than mission start time.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.1
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• pp.448-456
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• 2020

This study found that it is critical to consider farmers' intention to adopt new technology in order to facilitate the spread of new technology. Based on this assumption, the research team analyzed the following: factors that influence intention of adoption and marginal effects on those factors. The data were collected from 99 farmers who did not participate in the pilot projects on dissemination of new technologies developed by the Rural Development Administration (RDA). A total of 19 observed variables were set to measure seven latent variables: educational support; technical support; funding support; compatibility; trialability; observability; and antipathy. The intention to adopt new technology was established as the dependent variable. According to the ordered logit analysis, educational support, observability, and antipathy were found to have significantly affected the intention to adopt new technology; their odds ratio were 6.938, 2.716, and 0.501, respectively. According to the marginal analysis, educational support, observability, and antipathy were found to have significantly affected the intention to adopt new technology; their marginal effects were 20.2 %, 10.4 %, and -7.2 %, respectively. Therefore, this study suggests the following to facilitate the spread of new technology: first, provide quality support services through effective deduction; second, increase the visibility of new technology; and third, enhance the credibility of agricultural institutions by developing continuous relations with farmers to reduce their antipathy.

• Korean Security Journal
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• no.61
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• pp.9-38
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• 2019

As the scales & density of the Korean national infrastructures have been increased, they will be identified as rich and attractive potential targets for intensified North Korea's attack in the rear region and terrorism attack. In addition, due to changes in security environment such as drone threats and lack of security forces under the 52-hour workweek law, I think that it is the proper time point to reevaluate the effectiveness and appropriateness of the current physical protection system and its shift to a new system. In this study, the direction and improvement of the perimeter physical protection systems of the national infrastructures are to be studied from the viewpoints of its concepts of operations and design methodology, focusing on the nuclear power plant. The reason why we focus on nuclear power plants is because they cause wide-range and long-term damages caused by radioactive materials disperal and pollution, along with short-term damage caused by the interruption of electricity generation in the event of damage to nuclear power plants. With the aim of extracting improvement directions, as we will comprehensively review domestic research trends and domestic·overseas related laws, and consider Korea's specificity, we try to reframe the concept of operation - systematization, mobilization and flexibility -, and establish criteria on system change. In order to improve the technical performance of the new perimeter physical protection system, we study on high-fidelity·multi-methodology based integrated design methodology, breaking from individual silo-type design methods, and I suggest improvement of government procurement, its expansion to export business and other national infrastructure.

• Journal of Korean Tunnelling and Underground Space Association
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• v.22 no.3
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• pp.323-335
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• 2020

In this study, a series of site measurement of particulate and gases pollutants at five tunnels were carried out along with case studies to review the suitability of the current road tunnel ventilation design standards. Previous studies by other researchers have shown that the ratios of the level of measurement to the standard were 27.9%, 1.6% and 3.4% for TSP, CO and NOx, respectively. Those measured in this site study shows even lower ratios; the ratios were 2.6%, 0.8% and 0.3%, for TSP, CO and NOx, respectively. The particle size analysis of TSP for the five tunnels shows that PM10 including tire wear and re-suspended road dust exceeded 20.4%. This implies that non-exhaust particulate matter must be taken into account, since the current design standards for the particulate matter (visibility) include only the engine emission. Based on the recent research results, for vehicle emission rate and slope-speed correction factors, revision of ventilation design standards for pollutants is required. WRA (PIARC) also emphasizes the necessity of the ventilation design standards for pollutants. In addition, enactment of a new road tunnel ventilation system operation standard or guideline is strongly recommended when considering the low operating rate of the ventilation system with jet-fans.

• The Journal of the Korea Contents Association
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• v.19 no.10
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• pp.560-567
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• 2019

South Korea, which has entered an aged society, is about to enter a super-aged society in 2025. With the increase of an aging population, traffic accidents by aged drivers have been settled as a social problem. Now, when Korea is facing a super-aged society to come, a study was conducted to prevent traffic accidents that occur while the elderly people are driving through a disaster prevention design. For theoretical research, this study examined the concept and necessity of disaster prevention design, the present condition of an aged society, aged drivers' physical and cognitive characteristics, and the policies related to the forms of traffic lights the elderly people see. In addition, to propose the design, this study investigated and analyzed the traffic safety forms and colors of the International Standards Organization and proposed the first and second forms of the design of traffic lights for the gradual improvement of the traffic lights based on that. The first improved design form is a plan for displaying a triangle, an arrow with a large area, and a quadrangle in the lens of the head of the existing traffic lights, and the second improved design form is a plan for introducing a new traffic light head and forming the traffic light with a bigger triangle, an arrow with a large area and a quadrangular lens. Since it has a visually clearer form than the present traffic lights, it is expected that aged drivers who have physical and cognitive characteristics due to aging can secure better visibility and conspicuity and that they can make better reflex responses than they can now, also in the change of driving environment (rain and heavy snowstorm, etc.). In addition, it is expected that this study would be a preceding study to prepare standard guidelines on traffic safety signs other than traffic lights to be prepared for the super-aged society.

• The Journal of the Korea Contents Association
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• v.19 no.1
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• pp.404-412
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• 2019

The purpose of this study is to develop the usability evaluation contents based on the needs of different stakeholder's related to the usability of the product, and to derive the design direction and apply it as the evaluation standard by applying the product design based on the results. I created a stakeholder map for a fire detector product and identified stakeholders related to usability. Based on 3 factors(Physical, cognitive, emotional) of the usability evaluation, I conducted survey on the building users and the building managers who have different requirements. There are 12 directions (ease of installation, durability, maintainability, additional functionality, effectiveness, attractiveness, visibility, consistency of information, environmental harmony, consistency, Image suitability, reliability). Through weighted analysis of three usability evaluation factors, I found factors were ranked in the same order of importance, but they were different in importance figure. Based on the results of the survey, overall product usability aspects were improved but effectiveness and environmental coordination aspects needed to be improved.

• Journal of the Korean Society of Marine Environment & Safety
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• v.28 no.4
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• pp.525-532
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• 2022

The port of Mokpo operates the largest number of coastal passenger ships and routes in Korea. These coastal passenger ships pass through narrow channels in the south-west coast of Korea owing to the geographical effect. It is difficult to find a research for the safety of the marine traffic environment in the narrow channel used by coastal passenger ship. Therefore, in this study, the navigation safety of the target coastal passenger ship was analyzed in the narrow channel near the port of Mokpo using the Korea design standard for port and harbour facilities. As a result of the analysis, the width of the narrow channel between Maek-island and Dali-island is narrower than 1.5 times of the target ship's length over all, the degree of curvature of the narrow channel exceeds the standard value of 30°, and several fishing gears exist near the narrow channel. Finally, the following were suggested to improve the safety of navigation on the narrow channel: keeping one-way traffic during the day-time, and navigating through the designated fairway during night·visibility restriction·low tide.

• Journal of the Korean Society for Library and Information Science
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• v.56 no.4
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• pp.5-28
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• 2022

In this study, LD construction cases of overseas libraries were analyzed with focus on published datasets, reused vocabulary, and interlinked external datasets, and based on the analysis results, basic data on LD construction plans of domestic libraries were obtained. As a result of the analysis of 21 library cases, overseas libraries have established a faithful authority LD and conducted new services using published LDs. To this end, overseas libraries collaborated with other libraries and cultural institutions within the region, within the country, and nationally under the leadership of the library, and based on this cooperation, a specialized dataset was published. Overseas libraries used Schema.org to increase the visibility of published LDs, and used BIBFRAME for subdivision of description to define various entities and build LDs based on the defined entities. Overseas libraries have utilized various defined entities to link related information, display results, browse, and download in bulk. Overseas libraries were interested in the continuous up-to-date of interlinked external datasets, and directly utilized external data to reinforce catalog information. In this study, based on the derived implications, points to be considered when issuing LDs by domestic libraries were proposed. The research results can be used as basic data when future domestic libraries plan LD services or upgrade existing services.

• Journal of Korean Library and Information Science Society
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• v.53 no.4
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• pp.319-345
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• 2022

This study aims to investigate the perceptions of researchers and information professionals on scholarly journals and events hosted by the four primary associations for library and information science in Korea and to suggest improvements. The four associations include the Korean Society for Library and Information Science, the Korean Library and Information Science Society, the Korean Society for Information Management, and the Korean Biblia Society for Library and Information Science, and they co-funded this study. A total of six focus group interviews were conducted with 21 university professors, researchers, librarians, practitioners, and executive directors of associations who are actively engaged in research and academic activities. Findings presented, first, that the overall process of the journal article review and publishing needs to be improved to enhance the quality of the journals. Second, efforts should be made to increase the visibility of practice by increasing opportunities for information professionals to submit and publish manuscripts with findings from the field. Third, each journal can be specialized by differentiating the scope of journals, providing articles with findings in practice, and facilitating collaborations with scholars abroad or in other fields. To improve scholarly events, first, a large-scale academic conference can be held regularly, co-hosted by the four associations, promoting academic needs and social networking. Third, each association can specialize in academic events in collaboration with professional institutions and agencies. Fourth, the opportunities to participate in academic events should be increased for early-career researchers, practitioners, and graduate and undergraduate students.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2021.05a
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• pp.67-69
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• 2021

Weather radar images can be used in a variety of ways because of their high visibility in terms of visuals. In other words it has the advantage of being able to grasp the flow of weather phenomena using not only the raw data of the weather radar, but also the change characteristics between consecutive images. In particular image processing techniques are gradually expanding in the field of meteorological research, and in the case of image data having high resolution such as weather radar images it is expected to produce useful information through a new approach called image processing techniques. In this study the weather phenomena flow was calculated as a vector from the change of the weather radar image according to time interval with the optical flow method, one of the image processing techniques. The characteristics of the weather phenomena to be analyzed were derived through vector analysis resolution suitable for the scale of weather, vector interpolation in regions where no radar echo exists, and the removal of relative flow vectors to distinguish the flow of specific weather and the entire atmosphere. Through this study, it is expected that not only the use of raw data of weather radar, but also the widening of the application area of weather radar, such as the use of unique characteristics of image data, and the active use of image processing techniques in the field of meteorology in the future.