• Journal of Forest and Environmental Science
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• v.32 no.4
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• pp.384-391
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• 2016

In this study, regions infected by pine wilt disease were extracted by using object-based classification method (OB-infected region), and the characteristics of special distribution about OB-infected region were figured out. Scale 24, Shape 0.1, Color 0.9, Compactness 0.5, and Smoothness 0.5 was selected as the objected-based, optimal weighted value of OB-infected region classification. The total accuracy of classification was high with 99% and Kappa coefficient was also high with 0.97. The area of OB-infected region was approximately 90 ha, 16% of the total area. The OB-infected region in Age class V and VI was intensively distributed with 97% of the total. Also, The OB-infected region in Middle and Large DBH class was intensively distributed with 99% of the total. In terms of the topographic characteristics of OB-infected region, the damages occurred approximately 86% below the altitude of 200 m, and occurred 91% with a slope less than 10 degree. The damage occurred a lot in low hilly mountain and undulating slope. In addition, the accessibility to road and residential area from OB-infected region was less than 300 m in large part. Overall, it was figured out that artificial effect is stronger than natural effect with regard to the spread of pine wilt disease.

• Transactions of the Korean Society of Automotive Engineers
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• v.11 no.6
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• pp.205-212
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• 2003

This paper may provide a basic design data for the safer car seat mechanism and the quality of the material used by finding out the passenger's dynamic behavior when protected by seat belt during collision. A computer simulation with finite element method is used to accomplish this objective. At first, a detailed geometric model of the seat is constructed using CAD program. The formation of a finite element from a geometric data of the seat is carried out using Hyper-Mesh that is the commercial software for mesh generation and post processing. In addition to seat modeling, the finite element model of seat belt and dummy is formed using the same software. Rear impact analysis is accomplished using Pam-Crash with crash pulse. The part of the recliner and right frame is under big stress in rear crash analysis because the acceleration force is exerted on the back of the seat by dummy. The stress condition of the part of the bracket is checked as well because it is considered as an important variable on the seat design. Front impact model which including dummy and seal belt is analyzed. A Part of anchor buckle of seat frame has high stress distribution because of retraction force due to forward motion of dummy at the moment of collision. On the basis of the analysis result, remodeling and reanalysis works had been repeatedly done until a satisfactory result is obtained.

• Journal of The Korean Society of Grassland and Forage Science
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• v.30 no.4
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• pp.301-308
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• 2010

This study was carried out in the Chungnam National University grassland experimental field from October, 2007 to December, 2009 in order to find out the growth characteristics, seasonal anthesis distribution and botanical composition of the wildflowers which were altogether composed of 70% sheep fescue and 30% introduced wildflowers. The experimental species contained 23 species in total to which sheep fescue (fundamental turfgrass) and 22 introduced wildflowers belonged. At the time of the anthesis of the wildflowers, the average plant height was 29.7 cm at first growing season and 34.1 cm at second growing season. They bloomed out into eight colors, but into simplified two colors during August, September, and October. The blooming season leant toward April and June and from August there were lots of difficulties in the wildflower blooming and the maintenance of their consistency. The botanical composition of wildflowers, sheep fescue, and weeds were 21%, 64%, and 15% in the first growing season (2008) and 19%, 65%, and 16% respectively, in the second growing season (2009). Based on this result, cultivating the introduced wildflower grassland has more difficulty because there is some difficulty in the wildflower seasonal distribution and the maintenance of its consistency. And thus, the introduction of more various wildflower such as perennials and flowers blooming after summer, and the seed-mixture combination method should be studied.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2014.10a
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• pp.533-538
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• 2014

Power generator is one of the most important component of electricity generation system to convert mechanical energy to electrical energy. I t designed robustly to maintain high system reliability during operation time. But unexpected failure of the power generator could happen and it cause huge amount of economic and social loss. To keep it from unexpected failure, health prognostics should be carried out In this research, We developed a health prognostic method of stator windings in power generator with statistical data analysis and degradation modeling against water absorption. We divided whole 42 windings into two groups, absorption suspected group and normal group. We built a degradation model of absorption suspected winding using Fick's second law to predict upcoming absorption data. Through the analysis of data of normal group, we could figure out the distribution of data of normal windings. After that, we can properly predict absorption data of normal windings. With data prediction of two groups, we derived upcoming Directional Mahalanobis Distance (DMD) of absorption suspected winding and time vs DMD curve. Finally we drew the probability distribution of Remaining Useful Life of absorption suspected windings.

• Proceedings of the KIEE Conference
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• 2003.07a
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• pp.259-261
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• 2003

This paper suggests wireless diagnosis and monitoring system using SMS mode of mobile communication network for distribution transformer which could prevent electrical accident in the near future. Data are acquired by measuring the temperature of insulator oil in the distribution transformer and load current. Data acquisition of sensor using mobile communication network carried out filtering of sensor's output to optimize the size of send data Merit of this inspection method is that management, control and monitoring some transformers can be carried out using only one server. This inspection method will be the way of inspection to be worth spotlight in the near future because it is able to solve easily with the minimum facility inspection about state of transformer which is operating, to wide coverage about machine's wrong operation in other field.

• Journal of the Korean Wood Science and Technology
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• v.23 no.2
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• pp.77-82
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• 1995

With the aim to utilize pine wood(Pinus densiflora Sieb. et Zucc.) as an interior building materials, such as flooring material, monoethylene glycol(MEG) resin solution was impregnated into greenwood. Specimens of three different qualities, that is, normal wood, resinous wood and compression wood, were prepared. Distribution of resin element(phosphorus) in MEG resin solution-impregnated woods and preservative effectiveness against brown rot fungi(Tyromyces palustris and Serpula lacrymans) of these woods were investigated. The results were as follows: 1. The concentration of phosphorus into cell walls of resinous wood and compression wood was lower compared to that of normal wood. This shows that the quality of wood has an influence on the penetration of MEG resin solution into the wood. It was shown from a leaching test that MEG resin could be leached out easily from the cell walls. 2. The resinous wood and compression wood, even without MEG resin solution impregnation had high decay resistance. For normal wood, significant improvement of preservative effectiveness was observed after impregnation of MEG resin solution. It was shown that MEG resin was leached out from the woods after leaching test, resulting in the reduction of preservative effectiveness. From this result, suitability of MEG resin solution-impregnated woods as an interior materials was recognized.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.19 no.4
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• pp.363-367
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• 1986

Distributional patterns of Ulnung-do's Polychaetous annelid worms comprising 64 species out of 53 genera were divided into four zoogeographical groups with reference to the distribution of the world's polychaetous annelid worms; cosmopolitan, northern, temperate and tropical types. It was found out that there were 25 species of cosmopolitan type taking up $39\%$, 20 species of northern type, $31\%$, and 19 species of temperate type, $30\%$, but tropical type was not found. When compared with the polychaetous annelid worms of the neighboring coastal areas of the Yellow Sea, the east coast of U.S.S.R., Korea and Japan, those of Ulnung-do island were shown to have highest similarity to those of Yellow Sea follwed by the areas in the order named.

• Clean Technology
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• v.8 no.2
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• pp.67-76
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• 2002

Dewatered sludge of 400,000t/y from water treatment plants in Korea is being disposed through landfill and ocean dumping. However, the disposal is posing more and more serious environmental problems at the same time not only because of landfill site shortage in municipal suburbs, but because of the concern it will contaminate the oceans. In this study, the research on utilizing the sludge dried by flash dryer as covering soil in the landfill sites was carried out to solve these problems on environmental affinity. Both dewatered and dried sludge were exposed to the natural condition and observed according to the atmospheric changes. An experiment of soil engineering characteristics of the dried sludge and tests on mixed sludge(silty sandy soil : dried sludge = 10:90 ~ 30:70) such as particle size distribution, liquid and plastic limit, moisture content, specific gravity and compaction test were carried out. According to the compaction test, the compaction was confirmed as the optimum water content ratio was observed in the condition of SM-silty sand of particle size distribution, NP of liquid and plastic limit, 101.4% of moisture content, 2.04~2.12 of specific gravity. The results showed that dried sludges mixed with at least 30% of natural soil could be used as daily covering soil in the landfill sites.

• Korean Journal of Social Welfare
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• v.42
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• pp.107-138
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• 2000

Today, the public assistance program in Korea is provided mainly for the livelihood protection beneficiary in urban area. The fact that the urban community-centered program is also applied to the livelihood protection beneficiary in rural area brings about some problems in fitness and effectiveness of resource distribution. The purpose of my study is to present my opinion that the public assistance program for the rural community should be put in practice after being fully distinguished from the urban program for the effective distribution of limited social welfare resources to insure the minimum standard of living and seek the self-support contribution which is the purpose of the public assistance program. The subject for this study were livelihood protection beneficiaries living in both rural and urban area. And the study was carried out in this parts: first, the way of life in them, second, the contents of 6 main public assistance programs being carried out. Total number of the livelihood protection beneficiaries are 279 case: 143 case from 15 Dong in 5 cities, and 136 case from 15 Myun in 5 counties. And the social worker who are performing the public assistance programare consisted of 50 case: 25 case from 5 Dong in 5 cities, and 25 case from 5 Myun in 5 counties. This research reach the result that the differentiate performance of the public assistance program in rural community would be an effective device for self-support to be freed from the vicious circle of poverty.

• Journal of Microbiology and Biotechnology
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• v.18 no.5
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• pp.908-912
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• 2008

To achieve a higher succinic acid productivity and evaluate the industrial applicability, this study used Mannheimia succiniciproducens LPK7 (knock-out: ldhA, pflB, pta-ackA), which was recently designed to enhance the productivity of succinic acid and reduce by-product secretion. Anaerobic continuous fermentation of Mannheimia succiniciproducens LPK7 was carried out at different glucose feed concentrations and dilution rates. After extensive fermentation experiments, a succinic acid yield and productivity of 0.38 mol/mol and 1.77 g/l/h, respectively, were achieved with a glucose feed concentration of 18.0 g/l and $0.2\;h^{-1}$ dilution rate. A similar amount of succinic acid production was also produced in batch culture experiments. Therefore, these optimal conditions can be industrially applied for the continuous production of succinic acid. To examine the quantitative balance of the metabolism, a flux distribution analysis was also performed using the metabolic network model of glycolysis and the pentose phosphate pathway.