• Journal of Forest and Environmental Science
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• v.33 no.2
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• pp.105-112
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• 2017

The distribution and form of pine wood nematode (PWN) were investigated in Jinju-si and Sacheon-si areas, where infested with pine wilt disease (PWD). The average PWN population per g of the tubulation part in the wilted Japanese balck pine were 381.2 and 341 in Jinju-si and Sacheon-si, respectively. The PWN population per g of affected Japanese black pine with wilt rate below 60% were 556 and 518 in Jinju-si and Sacheon-si, respectively. The ratios of PWN and other plant-parasitic nematode in the wilted Japanse black pines were 48% vs. 52% in Jinju-si and 53% vs. 47% in Sacheon-si after exposure to PWD for 1 year. The survivorship of pine wood nematode in the sampled trees after 1 year was 0-10% in the Jinju-si area and 5-20% detected in the Sacheon-si area. In the forest areas affected by PWN, the highest survival rates were 37.2% and 39.8% at 25 cm diameter at breast height (DBH) in Jinju-si and Sacehon-si, respectively, while the highest wilt rates were 30.5% and 28.3% at 30 cm DBH in Jinju-si and Sacehon-si, respectively.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2006.05a
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• pp.17-24
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• 2006

We consider the sensor location problem (SLP) on a given sensor field. We present the sensor field as grid of points. There are several types of sensors which have different detection ranges and costs. If a sensor is placed in some point, the points inside of its detection range can be covered. The coverage ratio decreases with distance. The problem we consider in this thesis is called multiple-type differential coverage sensor location problem (MDSLP). MDSLP is more realistic than SLP. The coverage quantities of points are different with their distance form sensor location in MDSLP. The objective of MDSLP is to minimize total sensor costs while covering every sensor field. This problem is known as NP-hard. We propose a new integer programming formulation of the problem. In comparison with the previous models, the new model has a smaller number of constraints and variables. This problem has symmetric structure in its solutions. This group is used for pruning in the branch-and-bound tree. We solved this problem by branch-and-cut(B&C) approach. We tested our algorithm on about 60 instances with varying sizes.

• The Plant Pathology Journal
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• v.16 no.1
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• pp.36-42
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• 2000

The coat protein gene of iris severe mosaic potyvirus, which was isolated in Korea, ISMV-K, from iris plant was cloned and its nucleotide sequence was determined. The coat protein of the virus contained 252 amino acid residues, including five potential N-glyxosylation site motifs. The coat protein of ISMV-K has 99.1% and 98.4% sequence identities with those of the Netherlands isolate of ISMV (ISMV-Ne) form crocus for the nucleotide and amino acids, respectively. The coat protein of ISMV-K has 50.4% to 60.3% nucleotide sequence identities and 47.3% to 55.7% amino acid identities with those of other 21 potyviruses, indicating ISMV to be a distinct species of the genus. The coat protein of ISMV-K was closely related with bean yellow mosaic virus and clover yellow vein virus in the phylogenetic tree analysis among the potyviruses analyzed. ISMV was easily and reliably detected from virus-infected iris leaves by RT-PCR with a set of the virus-specific primers.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.21 no.5
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• pp.720-725
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• 2012

Sodium hypochlorite is used worldwide as a water disinfectant and in bleaching agent. Sodium hypochlorite applied to water initially undergoes hydrolysis to form free chlorine consisting of hypochlorous acid(HOCl) and hypochlorite ion($OCl^-$). For free chlorine determination, an electrochemical method is simple due to the electroactivity of free chlorine; it measures current and is free of most reagents. Amperometric free chlorine sensor has been developed with gold (Au)-based electrode. The 3-electrode free chlorine sensor whose working and counter electrodes were Pt exhibited excellent response to HClO at +400mV vs. Ag/AgCl/sat. KCl. In addition, the use of a pH error correction algorithm provided a reliable measurement of residual free chlorine in water sample without any pretreatment in the normal pH range(pH 6~8) of municipal water supply. The free chlorine sensor installed in on-line monitoring system could be used to continually monitor the level of residual free chlorine in real samples.

• Research in Plant Disease
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• v.26 no.2
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• pp.88-94
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• 2020

Recently, the severe dieback of apple trees resulting from soil-borne diseases has occurred in South Korea. The casual agents of dieback were surveyed on 74 apple orchards that had been damaged nationwide in 2016-2019. The number of apple orchards affected alone by Phytophthora rot, violet root rot, and white root rot was 31, 34, and 3, respectively. Also, the total number of mixed infection orchards was 6. Out of 9,112 apple trees affected by dieback, the trees damaged by Phytophthora rot, violet root rot, and white root rot were 3,332, 3,831, and 44, respectively. Moreover, the total number of mixed infection apple trees was 1,905. The provinces mainly affected were Gyeongnam, Gyeongbuk, Chungbuk, and Jeonbuk. The survey on these infected apple orchards will be available to form management strategy for the dieback that had been increased by soil-borne fungal pathogens.

• Journal of Environmental Science International
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• v.12 no.2
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• pp.119-124
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• 2003

An effective grafting method for jujube nursery trees was developed to shorten the operation time, improve the percentage of "takes" and shoot emergence, and form the better graft union. Out of 7 grafting methods the splice, modified scion Ono graft and the bark graft showed relatively short operation time during the grafting operation comparing to the modified rootstock Ono graft or the chip budding. Among these methods, the bark graft demonstrated 100% "takes", but the modified scion Ono graft or the standard Ono graft showed 58.3% of "takes". The percentages of the vegetative shoot emergence were 100% fir the bark graft, 70% f3r the modified scion Ono graft and lower emergence percent for the rest grafting methods. The union tissue formation for the modified scion Ono graft, the bark graft, or the whip-and-tongue graft was significantly larger than the standard Ono graft or the splice graft. In a close examination of the cross sectional areas of the graft union formation through the microscope, the bark graft was superior, the standard Ono graft was inferior and rest of the grafting methods were intermediate.ing methods were intermediate.

• Journal of Information Technology Services
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• v.15 no.1
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• pp.197-210
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• 2016

With the advent of text analytics, VOC (Voice of Customer) data become an important resource which provides the managers and marketing practitioners with consumer's veiled opinion and requirements. In other words, making relevant use of VOC data potentially improves the customer responsiveness and satisfaction, each of which eventually improves business performance. However, unstructured data set such as customers' complaints in VOC data have seldom used in marketing practices such as predicting service time as an index of service quality. Because the VOC data which contains unstructured data is too complicated form. Also that needs convert unstructured data from structure data which difficult process. Hence, this study aims to propose a prediction model to improve the estimation accuracy of the level of customer satisfaction by combining unstructured from textmining with structured data features in VOC. Also the relationship between the unstructured, structured data and service processing time through the regression analysis. Text mining techniques, sentiment analysis, keyword extraction, classification algorithms, decision tree and multiple regression are considered and compared. For the experiment, we used actual VOC data in a company.

• Fisheries and Aquatic Sciences
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• v.14 no.4
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• pp.295-301
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• 2011

We investigated the genetic structure of Korean and Japanese ayu Plecoglossus altivelis populations by examining 669 individuals from 14 populations using three microsatellite loci. Genetic variation did not differ significantly among the populations examined in terms of allelic number and heterozygosity. Korean populations were genetically close to each other, implying that persistent gene flow has occurred in these populations. This suggests that eastern populations in Korea form a single large population and all of the Korean populations are distinct from the Japanese populations. Pairwise population $F_{ST}$ estimates, principal component analyses, and a neighbor-joining tree showed that genetic separation between the southern and pooled eastern coast populations was probably influenced by restricted gene flow. Hierarchical analysis of molecular variance (AMOVA) revealed a weak but significant genetic structure among three ayu groups (eastern and southern coasts of Korea and the Japan coast), and no genetic variation within groups. The estimated genetic population structure and potential applications of microsatellite markers may aid in the proper management of ayu populations.

• Journal of the Korean Society for Nondestructive Testing
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• v.31 no.6
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• pp.609-615
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• 2011

Excitation and propagation of electromagnetic field of a cylindrical coil above an arbitrary number of conductive plates for pulsed eddy current testing(PECT) are very complex problems due to their complicated physical properties. In this paper, analytical modeling of PECT is established by Fourier series based on truncated region eigenfunction expansion(TREE) method for a single air-cored coil above stratified conductive structures(SCS) to investigate their integrity. From the presented expression of PECT, the coil impedance due to SCS is calculated based on analytical approach using the generalized reflection coefficient in series form. Then the multilayered structures manufactured by non-ferromagnetic (STS301L) and ferromagnetic materials (SS400) are investigated by the developed PECT model. Good prediction of analytical model of PECT not only contributes to the development of an efficient solver but also can be applied to optimize the conditions of experimental setup in PECT.

• Annual Conference on Human and Language Technology
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• 1999.10e
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• pp.297-303
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• 1999

오늘날 전산망을 통해 대량의 다양한 언어 정보가 일상 언어로 교환되고 있다. 따라서 대량의 이러한 정보를 효율적으로 처리할 수 있는 언어 정보 처리 시스템이 필요하다. Hausser (1999)와 이기용(1999)는 그러한 언어 정보 처리 시스템으로 데이터베이스 의미론을 주장하였다. 이 의미론의 특징은 자연언어의 정보 처리 시스템 구축에 상업용 데이터베이스 관리 시스템을 활용한다는 점이다. 이때 야기되는 문제 중의 하나가 표상(representation)의 문제이다. 그 이유는 언어학의 표상 방법이 데이터베이스 관리 시스템의 표상 방법과 다르기 때문이다. 특히, 관계형 데이터베이스 관리 시스템(RDBMS)에서는 테이블 (table) 형식으로 각종 정보를 표시한다. 따라서, 이 논문의 주안점(主眼点)은 언어학에서 흔히 쓰이는 표상 방법, 즉 문장의 통사 구조를 표시하는 수형(tree)이나 의미 구조를 표시하는 논리 형태(logical form), 또는 단어나 구의 특성을 나타내는 자질 구조(feature structure)를 테이블 형식으로 대체하는 방법을 모색하는 것이다. 더욱이 관계형 데이터베이스 관리 시스템에서는 테이블에 대한 각종 연산, 특히 두 테이블을 연결(link)하는 작업이 가능하고 이런 연산 과정을 통해 정보를 통합하거나 여과할 수 있기 때문에 관련 정보를 하나의 테이블에 표상하거나 정보 자료의 분산 저장과 자료의 순수성을 유지하는 것이 용이하다. 이 논문은 곧 이러한 점을 가급적 간단한 예를 들어 설명하는 데 그 목적이 있다.