• Proceedings of the KSRS Conference
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• v.1
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• pp.130-133
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• 2006

Three scatterometers will be launched by Europe, India, and China in the next few years and they will fly in tandem with QuikSCAT of the United States. The potential improvement in coverage will open up new operational and research applications.

• Journal of Communications and Networks
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• v.14 no.5
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• pp.578-587
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• 2012

One of the key elements in the emerging, packet-based long term evolution (LTE) cellular systems is the deployment of multiple femtocells for the improvement of coverage and data rate. However, arbitrary overlaps in the coverage of these femtocells make the handover operation more complex and challenging. As the existing handover strategy of LTE systems considers only carrier to interference plus noise ratio (CINR), it often suffers from resource constraints in the target femtocell, thereby leading to handover failure. In this paper, we propose a new efficient, multi-objective handover solution for LTE cellular systems. The proposed solution considers multiple parameters like signal strength and available bandwidth in the selection of the optimal target cell. This results in a significant increase in the handover success rate, thereby reducing the blocking of handover and new sessions. The overall handover process is modeled and analyzed by a three-dimensional Markov chain. The analytical results for the major performance metrics closely resemble the simulation results. The simulation results show that the proposed multi-objective handover offers considerable improvement in the session blocking rates, session queuing delay, handover latency, and goodput during handover.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.15 no.6
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• pp.69-77
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• 2012

This study observes the purchased lands in riparian areas of Suncheon City region and proposes a reasonable management method. For the study, the site surveying and analysis on the neglected purchased lands is executed, then, based on the site analysis result, the appropriate management method for each neglected purchased land is established. Each management method is approached from the ecological restoration perspective. According to site surveying and analysis of the neglected purchased lands, most of the sites were bare and agricultural lands. The reason for this is thought to be as when purchasing a land, the areas with higher nonpoint source pollution are bought preferentially. As for the dominant species coverage, 26% ($364,000m^2$) of the total neglected purchased land area in Sucheon City was covered with the dominated species, and for the exotic species coverage, 17% ($232,000m^2$) of the total neglected purchased land area in Sucheon City was covered with the exotic species. The survey site constituted of five different invasive species such as Japanese Hop (Humulus japonicus), Daisy Fleabane (Erigeron annuus), and Evening Primrose (Oenothera odorata). As for the natural succession on site, about 47% of the area showed poor natural succession process. The reason for this outcome is understood as having a lack of appropriate management for purchased lands. Based on the site surveying and analysis, especially the current management state of the and its location, the research site was categorized into preservation, restoration, and improvement sites. During the establishment of the ecological riparian belt, the comprehensive management for preservation, restoration, and improvement of the purchased lands should be executed.

• The Korean Journal of Ecology
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• v.21 no.5_3
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• pp.665-673
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• 1998

This study was conducted to clarified the relationship between bird community and forest structure and present the counterplan for protection and management of bird community from February 1993 to July 1995 at deciduous and coniferous forest within Mt. Nam area, Seoul, Korea. DBH distribution has not significant differences in each study site. Deciduous forest had more foliage coverage in all layers than coniferous forest. Total 41 species of birds, which were 16 species of resident, 14 species of summer visitor, 4 species of winter visitor, and 7 species of passage migrant were recrded in two study sites. Leaf use rate of birds was increased the increase of coverage. The number of breeding species and pairs, breeding density, and diversity index were greater in deciduous forest than coniferous forest. The number of species and pairs on bush-nesting and foraging guild were greater than other guilds. And the nuber of species and pairs on hole nesting guild were the fewest in nesting guild. Use rate of artificial nests for improvement of habitat quality was greater in coniferous forest than deciduous forest. Maintenance of bush layer, increase of coverage and leaf layer diversity, supply of artificial nests, management of large trees, and control of natural enemy were necessary for protection and management of bird community in Mt. nam area.

• Journal of Applied Reliability
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• v.17 no.4
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• pp.325-331
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• 2017

Purpose: There is active research that improves both reliability and fatigue life of structures which widely used in the aerospace fields of defense industry. The effects of three parameters (pressure, peening time, nozzle distance) on Almen intensity and coverage will be investigated by using the experimental and analyzed data. Methods: we employed a Box-Behnken design. Additionally, to verify the validity of the optimal condition obtained from experimental results, metallurgical analyses of the shot-peened aerospace part were conducted with respect to surface morphology, residual stress. Results: Optimal shot peening condition is determined as (distance, pressure, time) by optimizing simultaneously the two responses of intensity and coverage. At the optimal peening condition the prediction interval for Almen intensity is well within the required range. And, the validity of the condition was checked by using the real aerospace aluminum alloy plate. Conclusion: Shot peening introduces significant levels of compressive residual stress and induces improves both reliability and fatigue life of structures.

• The Korean Journal of Health Service Management
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• v.12 no.3
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• pp.13-26
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• 2018

Objectives: This study investigated how Korean daily newspapers frame the present government's health insurance coverage expansion policy, Moon Jae-in Care. Methods: A contents analysis was conducted to construct news frames represented in the four Korean daily newspapers' editorials and columns on Moon Jae-in Care during from April 2017 to April 2018. News text was classified into three different layers of frames: expressive element, narrative structure, and implied values. Results: The analysis revealed that the frequency of narrative frames was as follows: health system improvement (20.8%), public burden (14.6%), opposition by doctors (14.6%), and populism (12.5%). The financial sustainability accounted for 41.7% of the value frame, followed by procedural legitimation (18.8%), and coverage expansion (16.7%). The results also revealed that reported frames were different among newspapers: Chosun Ilbo tended to report in a negative tone, while Hankyoreh shinmun and Kyunghyang shinmun used a positive tone. Conclusions: This finding suggests that there are salient framings in reports on Moon Jae-in Care. Based on the results, the government needs to present a detailed financing plan on Moon Jae-in Care in detail. I discussed another implication of media frames results.

• The Journal of the Korea Contents Association
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• v.22 no.8
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• pp.94-105
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• 2022

The purpose of this study is to suggest improvement plan for a commentary on figure skating in Korea from comparing to NBCSN and MBC's coverage of the 2018 Pyungchang Olympic Games employing both of quantitative and text analysis. Results indicate that NBCSN and MBC's commentary on figure skating have definitely different characteristics in terms of expertise and dramatizing ability. The commentator of MBC frequently used monotonous and repetitive emotional expression and provided incoherent information in very automatic way. Whereas, NBCSN's comments expressed very diverse way on introduction of players, explanation of technique and evaluation, especially on dramatizing ability to contextualize combining players' performance and background information.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.4 no.1
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• pp.90-97
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• 2001

For improvement of water quality, $20m^2$ of artificial floating plant islands planted with Iris pseudoacorus, were installed in small pond on March, 1999. Small pond has surface area $1,000m^2$ and mean depth 1.5 m. The density of plants was 16 per $m^2$ by using jute pot. Environmental parameters such as COD, SS, T-N, T-P and planktons were biweekly measured from 29 March to 28 September. Because of the small portion of floating island, the effect for water quality improvement was not sufficient. But considering the data of plant growth and nitrogen and phosphorus uptake capacity of plant, about 40% of coverage by artificial floating island was needed for elimination of whole nutrients from inflow.

• Korea journal of population studies
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• v.17 no.1
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• pp.53-72
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• 1994

The historical study reveals that our ancestors had maintained a system which could produce data on population and households. The main purposes of maintaing the system at that time were taxation and conscription. At the present time, however, there are three major data sources which produce the statistics on pop-ulation and households in Korea : Civil Registration System, Resident Registration System and Popula-tion Census. These three systems are found to have some problems. there are some inherent problems in the regis-tration systems, such as problems in its coverage, accuracies in contents and timeliness in reporting the vital events and publishing the results. The population census has also non- sampling erors, such as errors in coverage, respone and non-response. Apart from the above mentioned problems, there are also conflicting problems arised from having three data sources, We can find some overlapping problems and difficulties in comparative studies. In the future, these problems should be considered for the improvement of the quality of statistics on population and household.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.06a
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• pp.1306-1309
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• 2003

In the present paper, finite element analyses were carried out to evaluate the most important feature of a stent, that is. high radial strength and flexibility. Palmaz-Schatz 154 stent and two new models(stent A, stent B) were selected because they are the most representatives of tubular stents. Finite element analyses for the stent system were performed using ABAQUS/Explicit code. As a result, Palmaz-Schatz 154 stent shows sufficient radial strength but it needs some improvement in general properties such as high flexibility, low elastic recoil, low longitudinal contraction and low metal coverage area. Other two models show that sufficient flexibility, foreshortening and longitudinal recoil.