• Journal of Korean Society of Transportation
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• v.25 no.2 s.95
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• pp.73-81
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• 2007

The purpose of this paper is to perform a basic study on the interaction between lanes, which can be achieved through analyzing traffic breakdown at the microscopic level. Using aerial photographic data for the microscopic analysis, this study analyzed the characteristics of traffic flow at a merging area. This research produced aggregated traffic data such as flows, speeds, and densities in 30 second intervals by lane for the macroscopic analysis and individual headway data by lane for the microscopic analysis. The paper contains an analysis of lane characteristics through flows, speeds, densities, and headway variations and also investigates the influence of ramp flows on mainline flows with space-time diagrams. Firstly, the merging area in this study is divided into three sections: before-merging, during-merging, and after-merging. The transition process was analyzed at each lane. Secondly, the breakdown was observed in detail with data divided in 50-foot units. The breakdown was checked through the relationships between ramp and freeway mainline flows, various techniques were proposed to analyze the breakdown, and the formation of breakdown was introduced as three stages in this study. In the near future, the findings of this study could contribute to determining the dynamic capacity on freeways by easily understanding changeable traffic breakdown patterns over time and space.

• Journal of Satellite, Information and Communications
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• v.4 no.2
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• pp.12-19
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• 2009

In the modern UAV systems, the role of radar payload has been increasing with its unique performance of day-and-night operation and see-through capability over hidden obstacles. Contrary to the satellite reconnaissance, UAV is expected to provide high resolution target detection and recognition capability while frequent flight missions would deliver enhanced SAR image and local information over the target area. STK(Satellite Tool Kit) is a professional space-analysis software widely used in all phases of a space system's life cycle. The simulation of STK is efficient and accurate relatively. In this paper, the author attempt to model the UAV operation and measure the expected SAR image quality. STK(Satellite Tool Kit) is employed to analyze UAV operation and produce SAR raw data. A SAR simulator is developed to produce high resolution SAR image for various ground targets.

• Journal of Korean Ophthalmic Optics Society
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• v.10 no.4
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• pp.339-345
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• 2005

In this paper, we studied the principle that correct the emmetropia to the aphakia using intraocular lens. At present, in an ophthalmic clinic, I.O.L which is using for correction of the vision clinically has presented how to prescribe more accurately by using optical method. To correct the Aphakia for the emmetropia, we considered that the basic cause of Ametropia was the refraction and the axial length. The correction principle is made equal to the Back Focal Length(BFL) and the vitreous length from lens to retina. For the confirmation of the correction principle, we used the Gullstrand number I eye model in emmetropia. For the myopia and hyperopia, we used the clinical data and replaced crystalline lens with intraocular lens.

• Research in Plant Disease
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• v.18 no.4
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• pp.381-386
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• 2012

Nematode fauna in Dokdo island was investigated for two years between 2008 and 2009. Population density and biomass were $239,500m^2$ (26,000-836,000) and $103.9mg/m^2$ (3.0-388.6), respectively. Total of 31 species of nematodes were identified : Acrobeloides is the most important genus with prominence value (PV) of 117.8, followed by Rhabditidae (PV = 81.9), Prismatolaimus (PV = 39.0), and Aphelenchoides (PV = 31.4). Among feeding group, bacteriovorus nematode composed 77% of density and 62% of biomass followed by plant-parasitic and fungivorus nematodes. A species of Pratylenchus having distinctive tail terminus is under study as a new species. Biological indices, Shannon and Wiener index (2.46), Simpson's diversity index (0.86), Species evenness (0.73), Species richness (1.30) indicate that nematode fauna in Dokdo island is diverse and unique. This study may give a general idea of nematode fauna at the Dokdo island.

• Journal of Korean Society of Forest Science
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• v.68 no.1
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• pp.1-10
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• 1985

This study was carried to analyze the structural change of interrelationships between the forestry including forest product processing and the other industrial sectors. The interindustry tables (19 setors) were drawn with the aid of the interindustry table published in 1970, 1975 and 1980 in connection with the forestry and forest product processing. In addition, the input coefficient and inverse matrix coefficient were calculated in the light of the 19 sector of interindustry tables. Owing to the change of economic structure during the period of 1970-1980, the importance of forest in Gross National Product has been decreasing. But it has shown that forestry is a kind of original industry having a great deal of intermediate demand which is constantly increasing. Therefore, forestry could be regarded as a supply industry to other industries. In addition, the import coefficient of forestry products in larger than that of other industries and it keeps increasing.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.41 no.4
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• pp.319-326
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• 2013

This paper describes the orbital dynamics operation results for the launch and early operations phase (LEOP) of KOMPSAT-3, which was successfully launched on May 18, 2012. At the initial phase, operational orbit determination was carried out using ground tracking data and GPS navigation solution. And, both in-plane and out-of plane maneuvers were executed in order to change the orbit from the injection orbit to the mission orbit. In addition, the accuracy of precise orbit determination was indirectly evaluated by overlapping method using GPS raw data of KOMPSAT-3 and international GNSS service data from worldwide-distributed ground stations. Currently, KOMPSAT-3 is operated in pre-defined mission orbit, and its various kinds of orbit data are generated and distributed to support the normal mission operations.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.2
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• pp.707-712
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• 2013

In patients with acute myocardial infarction (AMI), the delay from symptom onset to hospital arrival has a critical effect on morbidity and mortality. This study examined to find out the determinants of the prehospital delay in patients with AMI. The study sample consisted of 597 patients hospitalized with AMI between Jan and Dec 2009. Demographic, medical history, and clinical data were abstracted from the hospital medical records of patients with confirmed AMI, the prehospital delay was categorized as less than or greater than 6 hours. Older age, low socioeconomic status(medical aid), and low use of Emergency medical system were associated with delays in seeking emergency care for Acute myocardial infarction. Education programs to improve patient knowledge of acute coronary syndrome symptoms and promote patient responsiveness with regard to seeking medical care should be used to reduce the prehospital delay time, especially in the low socioeconomic group.

• The Journal of Korean Association of Computer Education
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• v.17 no.6
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• pp.135-146
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• 2014

The study has compared the effects in SNS-utilized instruction that each of self centric activities and social interaction added social activities affected self initiative, attitudes and self efficacy to information technology respectively. The research methods utilized the pre experimental design as nonequivalent experimental group. The data was analyzed by paired t-test and content analysis. The results showed that the SNS class utilized self-centric activities were effective in self-initiative and attitudes toward information technology, while social interaction added social activities were effective in not only self-initiative and the attitudes of information technology but also self efficacy of information technology. And content analysis of the effects of the education showed that information sharing, instancy and accessibility were advantageous but information security and privacy issues were problematic. That is, it was confirmed that when self-centric activities and social interaction activities were practised simultaneously in SNS-utilized instruction, the self initiative which learners planed and executed by themselves, the attitudes and self efficacy of information technology which were able to enhance learning ability and to show satisfaction to individual learning were improved.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.28 no.1
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• pp.38-48
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• 2010

The Gwanghalu garden which has a pond of approximately $6,000m^2$ around the pavilion at Namwon City, used as official uses consists of the various imaginary environmental elements such as moon palace as an immortal world, miniatured cosmology and law of nature. This study has focused on the interpretation of the imaginary environmental elements at 1) the name of garden structures, 2) the paintings on the structures, 3) the poems on the garden, and then emphasized on the values of imaginary environments at the historic sites which have been abandoned because of the Westernized scientific attitude in landscape design. Imaginary environment is the 3rd one above the natural and built environment which was a long traditional culture. Accordingly education on landscape architecture might pay attention to this lost environment, imaginary to give the people dream.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.3
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• pp.1515-1521
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• 2014

This study applies simulation-based education and care for acute myocardial infarction nursing students to investigate the effect of critical thinking, problem solving, and academic achievement of a single group before and after the raw experimental design. A total of 137 subjects were arbitration period September-October 2011, enforcement and arbitration were evaluated after simulation-based training six weeks total. Data analysis was performed using SPSS Win17.0, Paired t-test, the mean and standard deviation, Pearson's correlation coefficient was used. Research results of simulation-based training program to improve critical thinking, problem solving, and academic achievement were As increase critical thinking and problem solving ability was improved. whereas, Critical thinking skills and problem solving ability was no significant difference with academic achievement. Simulation-based training program to improve the practical skills of nursing students learning was found how useful it, that there is a need to take advantage of hands-on training in a variety of cases that can be common in the field of clinical scenarios developed by. To do this, It seems to be necessary to the development and operation more varied and appropriate hands-on training method.