• The Korean Journal of Pesticide Science
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• v.14 no.3
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• pp.241-246
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• 2010

Field experiments were carried out to establish economic threshold for com borer (Ostrinia furnacalis (Guen$\'{e}$e)) on waxy com plants by examining the number of adult insects caught in pheromone traps and the injury levels of waxy com which were artificially controlled. Adult com borers were lured into the pheromone traps during the whole growth period in five areas in Gangwon province including Chuncheon. The number of com borers trapped was the greatest in Chuncheon followed by Cheolwon and Hongcheon, and the same trend was observed for injury level of waxy com. Based on marketable yield data of waxy com plants related to the artificially-controlled injury levels at tassel stage, spray threshold was determined as the injury level of 11~15%, where the injury of com plants exceeded the economically admitting level.

• Korean journal of applied entomology
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• v.31 no.1
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• pp.45-49
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• 1992

Studies were conducted to control Spodoptera exigua in Allium fistulosum field using synthetic sex pheromone trap. Heavily, medium and lightly damagd fields at early transplanting time showed no differences in control effects after 8 weeks of establishment of pheromone traps in Allium fistulosum fields. Number of damaged leaves in each treated field was 0.2-3 individuals per 60 hills comparing with 33.2 individuals at non-treated field. Also, the numbers uf male adults attracted to pheromone traps were 1.8-5.0 individuals at the big inning of installation but increased to 25.8, 49.9, 74.9, and 77.4 individuals after 2, 4, 6, and 8 weeks, respectively. There was a negative correlation between amount of male adults attracted to pheromone traps and number of damaged leaves (r=-0.9572*). Number of adults attracted to various colored light trap for 30 days were 6 in red, 11 in white and none in blue comparing with 1,041 individuals in pheromone trap.

• Journal of Radiation Protection and Research
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• v.24 no.1
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• pp.1-7
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• 1999

Using the TBP slovent extraction method, a simple and precise method for determining uranium isotopes in the environment samples was developed. The soil sample was decomposed with $HNO_3$ and HF. Uranium isotopes were extracted with 15% TBP in $CCl_4$ from aqueous phase to organic phase, and Th fraction was removed with 8M HCl. Uranium fraction was purified in back extraction step with 1M HCl. Optimized electrode position conditions of uranium Isotopes were set using a new electrode position solution including a DTPA chelating agent. The new method of uranium isotopes determination was validated with a result of application to IAEA Reference Soils.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.22 no.9
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• pp.1179-1184
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• 2018

Korean travel agencies that have been utilizing the Internet passively feel threatened as global online travel agencies are quickly permeating the Korean travel market. Under these circumstances, this study conducted a focused analysis on how ICT affects the business environment of travel agencies. Based on the analyzed data, it also presents coping strategies for the Korean travel agencies. First, it is imperative to accelerate platform development to counteract the distribution structure of global tourism products. Second, it is essential that travel agencies actively utilize big data, the new paradigm of technology where data are generated at high speed, high volume, and for numerous purposes. Third, it is necessary to actively utilize a travel blog marketing strategy. As a communication tool for travel agencies, the continuing development of the Internet highlights the usefulness of marketing activities using blogs. Finally, it is essential to provide each customer more specialized travel consultancy.

• Journal of the Society of Naval Architects of Korea
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• v.33 no.4
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• pp.142-149
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• 1996

Pyramid type three roll bending machines are widely used in roll-bending process to produce singly curved plate. In forming singly curved plate, controlling the vertical displacement of the center roller is most important to acquire the shape required and automation system of the process. In this paper roller bending process is modeled as an elastic-plastic phenomenon and analyzed using beam theory and finite element method. In finite element analysis the workpiece is modeled by using beam elements and plane strain elements respectively. Through the analyses vertical center roller displacement is obtained to get constant curvature distribution along arc length. The relationship between center roller displacement and curvature in steady state as well as residual stress and strain along plate thickness direction are calculated through finite element analysis.

• Applied Biological Chemistry
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• v.31 no.2
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• pp.143-146
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• 1988

The effect of gamma irradiation on controlling infestation of insects on rice grain were investigated. The egg and larva stages of rice weevil (Sitophilus oryzae) were more radiosensitive than the pupal and adult stages. The complete mortal dose of the first two stages was 0.05kGy, while it was 0.5kGy in the second two stages. In indian-meal moth (plodia interpuctella Hubner), sterile doses of egg, larva, pupa and adult were 0.04 to 0.05, 0.05 to 0.06 and 0.2 to 0.25kGy, respectively. Therefore, the irradiation dose within 1.0kGy was considered to be effective for rice storage so far as reinfestation was prevented. Attractiveness of indian-meal moth toward the rice irradiated at 1.0 to 5.0kGy was non-significant in F-test.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.02a
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• pp.210-210
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• 2010

저항 구조를 가진 유기 쌍안정성 소자는 비휘발성 기억 소자 중에서 구조가 간단하고 제작비용이 저렴하며 플렉시블이 용이한 장점 때문에 많은 연구가 진행되고 있다. 유기물/무기물 복합재료를 사용한 유기 쌍안정성 소자 제작에 대한 연구는 많이 진행되어 왔지만, 넓은 에너지 밴드 갭을 가진 $SnO_2$ 나노 입자가 삽입된 고분자 박막을 기반으로 제작한 유기 쌍안정성 소자에 대한 연구는 상대적으로 미흡하다. 본 연구에서는 Poly(methyl methacrylate) (PMMA) 박막 안에 분산된 $SnO_2$ 나노 입자를 사용하여 제작한 유기 쌍안정성 소자의 전기적인 특성을 관찰하였다. 소자를 제작하기 위해 나노 입자의 전구체인 Tin 2-ethylhexanoate (95%) 2.4 mmol을 dibutyl ether (99.3%) 10 ml에 용해시킨 후, 용매열 화학적 방법을 사용하여 용매 안에서 $SnO_2$ 나노 입자를 합성하였다. 용매 안에 들어있는 1 wt%의 $SnO_2$ 나노 입자와 100 mg의 PMMA를 2 ml의 클로로벤젠에 용해하여 고분자 용액을 제작하였다. 하부 전극 역할을 하는 indium tin oxide가 증착된 유리 기판 위에 고분자 용액을 스핀 코팅하고, 열을 가해 용매를 제거하여 $SnO_2$ 나노 입자가 분산되어 있는 PMMA 박막을 형성하였다. 그 위에 Al 전극을 증착하여 기억 소자를 완성하였다. 제작된 유기 쌍안정성 소자의 전류-전압 (I-V) 측정 결과에서는 동일한 전압에서 서로 크기가 다른 전류가 흐르는 I-V 곡선의 히스테리시스 특성이 나타났다. 그러나 $SnO_2$ 나노 입자가 없는 PMMA 박막으로 형성된 유기 쌍안정성 소자에서는 I-V 곡선의 히스테리시스 특성이 나타나지 않았다. 따라서 PMMA 박막 안에 삽입된 $SnO_2$ 나노 입자가 유기 쌍안정성 소자의 메모리 효과에 결정적인 영향을 준 것을 알 수 있었다. 전류-시간 측정 결과에서는 소자의 ON/OFF 비율이 시간에 따라 큰 변화 이 없이 1000 사이클 이상 지속적으로 유지 하고 있음을 보여 줌으로써 유기 쌍안정성 소자를 장시간 사용할 수 있음을 나타내 주었다.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.25 no.9
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• pp.1144-1151
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• 2021

The pressing process is a compression process in which a product is made by applying force to a heated or unheated material to transform it into the desired shape. Due to the characteristics of press equipment that produces products through continuous compression for a short time, product defects occur continuously, and systems for solving these problems are being developed using various technologies. This paper proposes a real-time defect detection system based on an artificial intelligence algorithm that detects defects. By attaching various sensors to the press device, the relationship between equipment status and defects is defined and collected based on a big data platform. By developing an artificial intelligence algorithm based on the collected data and implementing the developed algorithm using an embedded board, we will show the practicality of the system by applying it to the actual field.

• Korean journal of applied entomology
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• v.61 no.1
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• pp.51-62
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• 2022

Numerous insect pests threaten the Korean orchard industry through feeding on various tissues of fruit trees. Generally, the control of economically important orchard pests is based on the use of chemical insecticides. Owing to growing concerns regarding the environmental and human health effects of insecticides, environment-friendly pest control strategies are urgently needed. Pheromones of orchard pests could lead to an environmentally safe control system based on mating disruption or mass trapping. This review summarizes the functions and compounds of known pheromones from 51 orchard pests in Korea. The pheromones identified to date from 14 species in the families Miridae, Aphididae, Diaspididae, Pseudococcidae, Rutelidae, Cecidomyiidae, and Eurytomidae and 26 species in the order Lepidoptera are female-produced sex pheromones that attract only males. In contrast, all known examples for 11 species in the families Alydidae, Pentatomidae, Thripidae and Cerambycidae are male-produced aggregation pheromones that attract both sexes. Research on pheromones in new pests, kairomones in key orchard pests, mating disruption dispensers to generate prolonged release of the pheromones, and trap design and trap location for mass trapping will be required for the expanded use of pheromones and other semiochemicals in orchard pest management in the future.

• The Journal of the Convergence on Culture Technology
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• v.9 no.3
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• pp.579-585
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• 2023

The purpose of this study is to explore keywords within stalking-related news articles according to political orientation through the text network analysis, and then to examine the implicit intentions. Selecting total 1,607 articles including 824 articles of the conservative press(The Chosun Ilbo, The Joongang Ilbo) and 783 articles of the progressive press(The Hankyoreh, The Kyunghyang Shinmun) reported from January 1, 2018 to December 31, 2022, this study explored the aspect of topic category drawn through the topic modeling technique based on LDA(Latent Dirichlet Allocation). In the results of this study, the common topics of the conservative and progressive press were improvement of the perception of gender-based violence, personal protection & intensity of punishment, and disclosure of stalkers' personal information. Regarding the topics differently shown in those two press, the conservative press showed stalkers' harmful act, and outline of 'murder case at Sindang Station' while the progressive press showed request for aggravated punishment on the 'murder case at Sindang Station', and eradication of sexual exploitation crime (in cyber space). The results of this study imply that there are changes in the type of reporting according to ideological opinions about stalking in news articles.