• Journal of the military operations research society of Korea
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• v.26 no.1
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• pp.56-69
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• 2000

A frequency assignment problem on time division duplex system is considered. Republic of Korea Army (ROKA) has been establishing an infrastructure of tactical communication (SPIDER) system for next generation and it will be a core network structure of system. VHF system is the backbone network of SPIDER, that performs transmission of data such as voice, text and images. So, it is a significant problem finding the frequency assignment with no interference under very restricted resource environment. With a given arbitrary configuration of communications network, we find a feasible solution that guarantees communication without interference between sites and relay stations. We formulate a frequency assignment problem as an Integer Programming model, which has NP-hard complexity. To find the assignment results within a reasonable time, we take a genetic algorithm approach which represents the solution structure with available frequency order, and develop a genetic operation strategies. Computational result shows that the network configuration of SPIDER can be solved efficiently within a very short time.

• Korean Journal of Breeding Science
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• v.40 no.4
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• pp.499-502
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• 2008

A new gerbera variety 'Yellow Wing' was released by the National Horticultural Research Institute (NHRI) in 2007. A cross was made between 'Gold Finger' with yellow and single and 'Yellow Springs' with yellow and spider in 2004. After investigation of the characteristics for 4 years (from 2004 to 2007), it was selected specially for the use of cut-flower. 'Yellow Wing' is a vigorous cultivar with yellow (RHS YO14B), green center and spider type. The flower diameter is 10.6cm. And inner ray floret and disc diameter is 2.83cm and 2.03cm, respectively. It produces a large yield with continuous supply of flowers and has adequate peduncle height and brilliant color. We believe that 'Yellow Wing' has a great potential for expanding cultivated area of domestic gerbera cultivar and increasing farmers-income.

• Journal of Species Research
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• v.11 no.2
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• pp.94-97
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• 2022

Linyphiidae Blackwall, 1859 is one of the most diverse and largest families within the order Araneae Clerck, 1757. Of the currently 60 valid species of the genus Neriene Blackwall, 1833 worldwide, 10 species are distributed in Korea. The males of the new sheet-web spider Neriene bovista sp. nov. were recently collected with a sweep net between the shrubs of mixed forests from the hilly valley with well conserved nature in Uljin-gun, Gyeongsangbuk-do (the middle east coast region) during a seasonal survey of the spider fauna in hilly terrains in 2017-2018. The present study describes a new sheet-web spider, Neriene bovista sp. nov. with a diagnosis, detailed description, morphological illustrations, and a distribution map from Korea. The new species has a characteristic mushroom-like tip of the terminal apophysis, the truncated tip of anterior projection, and the bifurcated lateral projection of the lamella compared to the congeners of the genus Neriene Blackwall, 1833.

• Korean Journal of Environmental Biology
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• v.35 no.4
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• pp.476-491
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• 2017

The water spider (Argyroneta aquatica), a rare member of its species, is one of the few insects known to live under water all over the world. In Korea, the water spider can be found only in the Eundae-ri, Yeoncheon, Gyeonggi province, where they are designated as a natural monument. However, loss of habitat is obvious, as the Eundae-ri wetland undergoes hydrarch succession. Loss of habitat has a direct impact on the water spider population. Thus protective measures for the water spider are needed to preserve the water spider habitat. In this study, a sweeping and visual survey of insect species was conducted in the water spider habitat from May to September 2015. The characteristics of each one of the different insect species and the community features were analyzed in this study. A total of 3,929 insects representing 276 species from 13 orders collected for the analysis. The most frequently collected insects from the Order Hemiptera represented 24.2% of total species and 82.3% of the total number of insects. Community analyses showed dominance, diversity, evenness, and richness indices of 0.23, 2.27, 0.41, and 31.2, respectively. Compared with the previous survey data, these results showed that reduction of the spider's wetland habitat caused the most commonly collected insects to adapt and spread to the surrounding terrestrial environment.

• Korean Journal of Environmental Biology
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• v.27 no.3
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• pp.237-243
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• 2009

The giant crab spider genus Sinopoda in Korea is reviewed with detailed illustrations of male palpal organs. Three species, S. forcipata, S. stellatops, S. koreana are recognized with newly collected specimens. The first species is recorded newly in Korean spider fauna. A key to the species of the Korean Sinopoda spiders are also provided.

• Proceedings of the Zoological Society Korea Conference
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• 2003.08a
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• pp.130.1-130
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• 2003

No Abstract, See Full Text

• Korean journal of applied entomology
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• v.35 no.3
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• pp.266-272
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• 1996

The selective tox\ulcornercity of fenpyroximate to the predatory mite Amblyseius womersleyi and the twospotted spider mite Tetranychus urticae was evaluated. Adult females and eggs of both species were placed on bean leaf dis~sd ipped in several concentrations of fenpyroximate. Fenpyroximate was much less toxic to A. womersleyi than to T. urticae. Although the survival of adult females of A. womersleyi tended to decrease with increasing fenpyroximate concentration, 58-74% of predators remained alive at concentrations of 6.25-50 ppm. However, reproduction of predators was not significantly reduced at any of the concentrations tested. At 6.25-50 ppm, 32-40% of twospotted spider mite adult females survived but all survivors were immobilized. Moreover, reproduction of twospotted spider mites was reduced with increasing fenpyroximate concentration. Fenpyroximate did not affect the hatch of A. womersleyi eggs or the development of immature predators. Although survival of immature predators decreased with increasing fenpyroximate concentration, 16-48% of immature predators reached adulthood at 6.25-50 ppm. However, all immature spider mites failed to develop to adulthood at 6.25-50 ppm. Adult female predators survived on a diet of twospotted spider mites intoxicated with fenpyroximate, and their fecundity and sex-ratio of the progeny were not substantially affected. Fenpyroximate at selective sublethal concentrations (6.25-12.5 ppm), therefore, could be of value in adjusting predatorlprey ratio in integrated management of twospotted spider mites.

• Animal cells and systems
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• v.3 no.2
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• pp.161-165
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• 1999

Nephila clavata, a golden orb-web spider, was studied at two different field sites with respect to web size, height, and orientation. A majority of spiders at Site 1 (a band of shrub bush) built their webs parallel or nearly parallel to the edge of the bush. Similarly, at Site 2 (near a pond), most webs were aligned with the shoreline of the pond. Among the possible determining factors for the observed patterns of web orientation, wind and light did not appear important. Instead, the movement direction of insect prey appeared largely responsible. Disproportionately more webs faced outside the bush and toward the pond than inside the bush and away from the pond at Site 1 and 2, respectively. Such trend was more apparent for larger spiders with larger webs.

• Korean journal of applied entomology
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• v.18 no.4 s.41
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• pp.149-152
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• 1979

The relative toxicity of some of the insecticides which have been used for the control of paddy rice insect pests in Korea was evaluated in the laboratory with the brown planthopper (BPH) Nilaparvata lugens, and a predaceous paddy spider Pirata subpiraticus. In order of the relative toxicity (LD5O value to spider/LD50 value to BPH) were PAP (0.4), MPP(0.1), MEP(1.8), diazinon(2.8), carbofuran(7.5), NAC(11.3), BPMC(17.5), Pyridaphenthion(35.9) and MIPC(65.7). MIPC and Pyridaphenthion were considered as having the desirable selective toxicity for the spider and the BPH.

• Biomaterials and Biomechanics in Bioengineering
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• v.2 no.4
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• pp.249-269
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• 2015

A problem faced by oil companies is the maintenance of the location register of pipelines that cross the surf zone, the regular survey of their location, and also their inspection. A survey of the state of art did not allow identifying operating systems capable of executing such tasks. Commercial technologies available on the market also do not address this problem and/or do not satisfy the presented requirements. A possible solution is to use robotic systems which have the ability to walk on the shore and in the surf zone, subject to existing currents and ripples, and being able to withstand these ambient conditions. In this sense, the authors propose the development of a spider crab biologically inspired robot to achieve those tasks. Based on these ideas, this work presents a biomechanical study of the spider crab, its modeling and simulation using the SimMechanics toolbox of Matlab/Simulink, which is the first phase of this more vast project. Results show a robot model that is moving in an "animal like" manner, the locomotion, the algorithm presented in this paper allows the crab to walk sideways, in the desired direction.