• Title/Summary/Keyword: Traps

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Characteristics of lost fishing gear distribution on the sea bed around gillnet fishing ground for yellow croaker in the near sea of Jeju, Korea (제주도 근해 참조기 유자망 어장의 폐어구 분포현황)

  • Kim, Byung-Yeob;Seo, Du-Ok;Choi, Chan-Moon;Lee, Chang-Heon;Chang, Dae-Soo;Oh, Taeg-Yun;Kim, Yeong-Hye;Kim, Jung-Nyun
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.46 no.4
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    • pp.441-448
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    • 2010
  • This paper was concentrated on the distribution and the composition of lost fishing gear on the sea bed around yellow croaker fishing ground in the near sea of Jeju, Korea from April to October 2009 in order to improve the fishery environment. Recovering lost fishing gears was carried out total 10 times with a trawlnet along the isobath. As the result, it seems reasonable to conclude that the amount of lost fishing gear has a deep connection with the dip of the sea bed as well as the fishing gear scale, fishing ground and so on. The amount of recovered lost fishing gears were in order of gillnets, dragged gears, traps and ropes. In particular, traps were recovered almost every time within the survey area.

A Survey of the Aphids in Sulchon Area (I) (감자바이러스 매개진딧물 밀도조사(I))

  • Yoon Soon Ki;Choi Seong Sik
    • Korean journal of applied entomology
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    • v.9 no.1
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    • pp.43-48
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    • 1970
  • To investigate provincial seed Potato Production farms, a Preliminary survey on the local population of the aphids was made in Sulchon alphine area, Mooju-Goon, Chollapuk-Bo where the climatic conditions were almost same as those of Taegwanryong Kangwon-Do, where Alpine Experimental station is located. This area stands from 650 to 900 metres above the sea level and divided three location of A. B, C, by altitude. A stands at 900 metres above the sea level. B at 750 metres and C at 650 metres. A and B divided three points: Al, A2, A3, and Bl, B2, B3- and divided four points-Cl, C2, C3, C4- at the distance of 300 metres apart each other. The traps were operated from July 21 to October 31, 1969. Otherwise, the traps established at Suwon (inland) and Taegwanryong where Alpine Experimental Station. A total of some 70 species including five virus vector species were identified. The Numbers of species at 10 locations, Suwon and Taegwanryong are as follows; Al-34, A2-38, A3-29, B1-25, B2-26, B3-29, C1-27, C2-14, C3-32, C4-37, species (Table 1), Suwon-49 species (including 5 virus vectors species), Taegwanryong-22 species (including 4 virus vector species). The aphids are shown in Table 1 and the Vectors are as follows: 1. Aphis gossypii Glover 2. Aulacorthum solani (Kaltenbach) 3. Lipaphis erysimi (Kaltenbach) 4. Myzus persicae(Sulzer) 5. Phorodon humuli (Schrank) Numbers of vectors versus total aphid at each locations, including inland (Suwon) and alpine area (Taegwanryong) where Alpine Experimental Station are as Fig. 1. Of a total 8,902 aphids, 6,400 $(80\%)$ were Tetraneura sp. The number of aphids devoid of the number of Tetraneura sp. are as follows; (Numbers means mean of each locations) A; 215. B; 115, C; 176 and Suwon; 2,952, Taegwanryong; 247. Densities of aphids at the locations is lower :han those at Suwon and Taegwanryong. And density of vectors at the locations, at ranged from 11 to 37, is love. than those at inland (Suwon; 197) and alpine area (Taegwanryong; 90). Thus, this area is suitable for seed potato production as Multiplication field.

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Estimation of Link-Based Traffic-Related Air Pollutant Emissions and the Exposure Intensity on Pedestrian Near Busy Streets (유동인구 밀집지역 인근의 도로구간별 배출량 산정 및 보행자 노출 강도 평가)

  • Lee, Sangeun;Shin, Myunghwan;Lee, Seokjoo;Hong, Dahee;Jang, Dongik;Keel, Jihoon;Jung, Taekho;Lee, Taewoo;Hong, Youdeog
    • Journal of ILASS-Korea
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    • v.23 no.2
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    • pp.81-89
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    • 2018
  • The objective of this study is to estimate the level of exposure of traffic-related air pollutants (TRAPs) on the pedestrians in Seoul area. The road network's link-based pollutant emission was calculated by using a set of mobile source emission factor package and associated activity information. The population information, which is the number of pedestrian, was analyzed in conjunction with the link-based traffic emissions in order to quantify exposure level by selected 23 spots. We proposed the Exposure Intensity, which is defined by the amount of traffic emission and the population, to quantify the probability of exposure of pedestrian. Link-based traffic NOx and PM emissions vary by up to four times depending on the location of each spot. The Hot-spots is estimated to be around 1.8 times higher Exposure Intensity than the average of the 23 selected spots. The information of Exposure Intensity of each spot allows us to develop localized policies for air quality and health. Even in the same area, the Exposure Intensity over time also shows a large fluctuation, which gives suggestions for establishing site-specific counter-measures.

Species and Seasonal Occurrences of Sericinae, Melolonthinae, and Rutelinae Chafers Captured by Blacklight Traps in Suwon and Chonju (수원과 전주 지방에서 blacklight trap에 유인된 우단풍뎅이아과, 검정풍뎅이아과 및 줄풍뎅이아과 풍뎅이의 종류와 발생 소장)

  • 김기황;강여규
    • Korean journal of applied entomology
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    • v.32 no.4
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    • pp.414-419
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    • 1993
  • Species and seasonal occurrences of Sencinae, Melolonthinae and Rutelinae chafers captured b by blacklight traps were investigated from 1989 to 1991 in Suwon and Chonju. Numbers of s species captured in Suwon and Chonju were 6 and 6 for Sericinae, 8 and 7 for Melolothinae, 7 a and 8 for Rutelinae, 21 and 21 in total, respectively. Species with more captures from both districts in each subfamily were Maladera orientalis of Sericinae, Holotrichia morosa and H. diomphalia of Melolonthinae, and Anomala corpulenta, and A. rufocuprea of Rutelinae. Adults of t the above five species were captured 1O~20 days earlier in Chonju than in Suwon. H. d diomphalia adults occurred mamly In odd years in Chonju, which is the same pattern as in S Suwon.

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Simulation of Threshold Voltages for Charge Trap Type SONOS Memory Devices as a Function of the Memory States (기억상태에 따른 전하트랩형 SONOS 메모리 소자의 문턱전압 시뮬레이션)

  • Kim, Byung-Cheul;Kim, Hyun-Duk;Kim, Joo-Yeon
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • v.9 no.1
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    • pp.981-984
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    • 2005
  • This study is to realize its threshold voltage shift after programming operation in charge trap type SONOS memory by simulation. SONOS devices are charge trap type nonvolatile memory devices in which charge storage takes place in traps in the nitride-blocking oxide interface and the nitride layer. For simulation of their threshold voltage as a function of the memory states, traps in the nitride layer have to be defined. However, trap models in the nitride layer are not developed in commercial simulator. So, we propose a new method that can simulate their threshold voltage shift by an amount of charges induced to the electrodes as a function of a programming voltages and times as define two electrodes in the tunnel oxide-nitride interface and the nitride-blocking oxide interface of SONOS structures.

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Thermoluminescence of Rb2LiCeCl6 Halide Scintillator (Rb2LiCeCl6 할라이드 섬광체의 열형광 특성)

  • Kim, Sunghwan
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.15 no.2
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    • pp.1211-1215
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    • 2014
  • We developed a new $Rb_2LiCeCl_6$ scintillator and determined the scintillation and thermoluminescence properties of the scintillator. The emission spectrum of $Rb_2LiCeCl$ is located in the range of 350 ~ 410 nm, peaking at 368 nm and 378 nm, due to the 4f ${\rightarrow}$ 5d transition of $Ce^{3+}$ ions. The fluorescence decay time of the crystal is composed two components. The fast component is 71 ns (85%) and the slow component is 405 ns (15%) of the crystal. The after-glow is caused by the electron and hole traps in the crystal lattice. We determined physical parameters of the traps in the crystal. The determined activation energy(E), kinetic order(m) and frequency factor(s) of the trap are 0.75 eV, 1.48 and $3.0{\times}10^8s^{-1}$, respectively.

The Pattern of Seed Rain in the Broadleaved-Korean Pine Mixed Forest of Xiaoxing'an Mountains, China

  • Jin, Guangze;Xie, Xingci;Tian, Yueying;Kim, Ji Hong
    • Journal of Korean Society of Forest Science
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    • v.95 no.5
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    • pp.621-627
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    • 2006
  • This study was conducted to understand the pattern and characteristics of seed rain in the broadleaved-Korean pine mixed forest. We established 287 $0.5m^2$ circular seed traps and collected and identified fallen seeds in the traps every two weeks in $150m{\times}150m$ sample plot of the permanent nine hectare of experimental plot in 2005. The overall average density of seed rain was $864.2/m^2$. The seeds of Betula costata Betula costata had the highest number of fallen seeds as $676.0/m^2$ (78.2%), followed by Abies nephrolepis as $57.5/m^2$, B. platyphylla as $37.9/m^2$, Tilia amurensis as $32.2/m^2$, Acer ukurunduense as $17.0/m^2$, A. tegmentosum $14.8/m^2$, and so on. Pinus koraiensis was recorded only $2.5/m^2$ of fallen seeds mainly owing of Korean pine had low rate of purity due to the animal and microbiological predation. Most of seed dispersal have started from the middle to late August and come to an end on the middle of November. The peak time of seed dispersal varied depending on the species. The rate of pure seed by dispersal time varied according to the species, thereupon the aspect of predation and the rate of blasted seed which had influence on the rate of purity also varied according to the species. The density of Korean pine seed rain in the forest gap was significantly different at $P{\leq}0.05$ from in the closed canopy. But the other species had no difference among canopy coverage.

Attack Surface Expansion through Decoy Trap for Protected Servers in Moving Target Defense

  • Park, Tae-Keun;Park, Kyung-Min;Moon, Dae-Sung
    • Journal of the Korea Society of Computer and Information
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    • v.24 no.10
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    • pp.25-32
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    • 2019
  • In this paper, we propose a method to apply the attack surface expansion through decoy traps to a protected server network. The network consists of a large number of decoys and protected servers. In the network, each protected server dynamically mutates its IP address and port numbers based on Hidden Tunnel Networking that is a network-based moving target defense scheme. The moving target defense is a new approach to cyber security and continuously changes system's attack surface to prevent attacks. And, the attack surface expansion is an approach that uses decoys and decoy groups to protect attacks. The proposed method modifies the NAT table of the protected server with a custom chain and a RETURN target in order to make attackers waste all their time and effort in the decoy traps. We theoretically analyze the attacker success rate for the protected server network before and after applying the proposed method. The proposed method is expected to significantly reduce the probability that a protected server will be identified and compromised by attackers.

Seasonal Prevalence of Mosquitoes Collected from Light Traps in Gyeongsangnam Province, Republic of Korea (2013-2014)

  • KIM, Dong-Min;NOH, Byung-Eon;HEO, Jeonghoon;LEE, Wook-Gyo;YANG, Sung-Chan;LEE, Dong-Kyu
    • Entomological Research
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    • v.48 no.5
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    • pp.439-447
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    • 2018
  • Adult mosquito surveillance was conducted from 2013 through 2014 at four cattle sheds, a wild bird refuge, and two residential areas located in Gyeongnam Province in the Republic of Korea. Adult mosquitoes were collected in black light traps from April 1, through November 30. Mosquito surveillance was conducted to figure out population densities of vector mosquitoes, possibly invaded mosquitoes and identify various virus infections at the selected sites. A total of 107,466 females comprising 14 species and 7 genera were collected from 2013 to 2014. The most common species collected were Culex tritaeniorhynchus Giles (63.8%), Anopheles sinensis s.l. (18.9%), Aedes vexans nipponii (Theobald) (7.7%), and Culex pipiens Coquillett (5.1%). Trap indices (TIs) varied widely for species over their range, due to geographical distribution and degree of association with rural and urban communities. The most collected An. sinensiss.l. and Cx. tritaeniorhynchus appeared at a cow shed in Hapcheon (TI 347.5) and a pigsty in Daejeo-1-dong, Busan (TI 1,040.8), respectively, due in part to their situation near breeding sites such as rice paddies. The bi-weekly population densities for mosquito species were variable for each of the years, apparently as a result of variable annual weather conditions. None of the mosquito species collected tested for the flavivirus including Japanese Encephalitis Virus, West Nile Virus, Dengue Virus, and Zika Virus infections by polymerase chain reaction (PCR) assay were positive.

Effect of Habitat Diversity through Comparison of Spider Diversity between Upland and Paddy Fields in Agroecosystems of South Korea (농업생태계인 밭과 논에서 거미의 다양성 비교를 통한 서식지 중요성 연구)

  • Nam, Hyung-Kyu;Song, Young-Ju;Eo, Jinu;Kim, Myung-Hyun
    • Korean Journal of Ecology and Environment
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    • v.52 no.2
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    • pp.151-160
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    • 2019
  • The study of spiders that function as predators in agroecosystem can broaden the understanding of agroecosystems. This study investigated the effect of heterogeneity at different spatial scales on richness and abundance of spiders in upland and paddy fields. We collected 48 samples using pitfall traps at upland and paddy fields, respectively. The total species richness of spiders estimated by sample- and coverage-based rarefaction and extrapolation curves. The total species richness was high in the upland fields at the total study sites, whereas the average species richness per study site was high in the paddy fields. We confirmed that the diversity enhancement of spiders was influenced by the structural complexity of habitat at field-scale, and crop diversity at broader scale.