• Applied Microscopy
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• v.51
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• pp.11.1-11.9
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• 2021

Spider capture silk is a natural scaffolding material that outperforms most synthetic materials in terms of its combination of strength and elasticity. Among the various kinds of silk threads, cribellar thread is the most primitive prey-capturing type of spider web material. We analyzed the functional organization of the sieve-like cribellum spigots and specialized calamistral comb bristles for capture thread production by the titanoecid spider Nurscia albofasciata. The outer cribellar surface is covered with thousands of tiny spigots, and the cribellar plate produces non-sticky threads composed of thousands of fine nanofibers. N. albofasciata cribellar spigots are typically about 10 ㎛ long, and each spigot appears as a long individual shaft with a pagoda-like tiered tip. The five distinct segments comprising each spigot is a defining characteristic of this spider. This segmented and flexible structure not only allows for spigots to bend individually and join with adjacent spigots, but it also enables spigots to draw the silk fibrils from their cribella with rows of calamistral leg bristles to form cribellar prey-capture threads.

• Congress of the korean instutite of fire investigation
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• 2010.12a
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• pp.63-79
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• 2010

It is found to the arc trace on the junction termination of 345kV cable. According to the analysis of the cable material is judged to be good. Manufacturing and design problems are not considered. In construction defects, it was estimated to the low level of insulation oil. In the majority of the arc trace appeared XLPE is found. However, there is no Soots mark, yellow band has not been confirmed, not associated with a radial arc of the spider leg is not evidence. In other opinions, void, contamination or jut are not found on the inside of XLPE. Thus, by the attachment of the impurities in surface of XLPE insulation is judged to the breakdown.

• Animal cells and systems
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• v.10 no.2
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• pp.49-64
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• 2006

Two spider species of the genus Asiacoelotes collected from various areas of South Korea are reviewed with spination on each leg, detailed illustrations including trichobothrium patterns and SEM photographs of male palpal organs and female epigynum. These two species, A. songminjae (Paik &Yaginuma, 1969) and A. insidiosus (L. Koch, 1878), have been confused in Korea and Japan because they were previously incompletely described. A. songminjae is redescribed from the neotype and is here synonymized with A. tropidosatus (Wang & Zhu, 1991). A. insidiosus is recorded for the first time in Korea.

• Animal Systematics, Evolution and Diversity
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• v.24 no.1
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• pp.143-145
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• 2008

The first known males of the spider Alloclubionoides ovatus (Paik, 1976) from Korea are described with detailed illustrations, spination of each leg and trichobothrium patterns. Males have a large conductor expanded curvedly 'p'-shaped with thin membrane of distal end surrounded the linear embolus and slender embolus penetrating tegulum.

• Animal Systematics, Evolution and Diversity
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• v.24 no.1
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• pp.33-38
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• 2008

A ground gnaphosid spider, Drassyllus shaanxiensis Platnick and Song, 1986 is reported for the first time in Korea. This species is described with detailed illustrations, leg spination, trichobothrium patterns, and SEM photographs of male palpal organ and female epigynum.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.24 no.8 s.179
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• pp.2065-2073
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• 2000

In this paper, we present a wall climbing robot whose gate pattern takes after those of specialized climbing animals such as spiders. Characteristic features of the biological locomotion are partly realized in the design of the mechanism. The robot has two legs and a trunk. Each one-dof leg with suction pads is driven by a motor which employs a closed loop linkage mechanism, and the trunk with suction pads steers the whole body of the robot using a motor. By generating adequate trajectories of the leg and simultaneously alternating the suction pattern between the legs and the trunk, we can achieve the spider like motion. The proposed idea is implemented in a robot and some tests are performed to evaluate its performance.

• Korean journal of applied entomology
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• v.59 no.3
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• pp.209-215
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• 2020

Debates over the ecological and public health impacts of aerial pesticide sprays are increasing. This is particularly true for controlling Monochamus beetles, which are vector insects of pinewood nematodes. In 2017, adult female orb-web spiders, Trichonephila clavata, were sampled from pine forests in Yangsan-si, Gyeongsangnam-do, Korea, where the aerial pesticide spray, fenitrothion or thiacloprid, was used for several decades. The biological traits of the spiders (body weight, body length, carapace width, and total hind leg length) were compared among treatment sites (no-spray, sprayed three times, and sprayed five times), and differences were observed. The body length, carapace width, and total hind leg length of the spiders in the sprayed areas were significantly shorter than in the no-spray area, but there were no differences between the area sprayed three or five times. These results indicate that repeated exposures to an aerial pesticide spray can alter morphological parameters, which influences population-level fitness. Future studies should monitor the spider long-term responses to pesticides (a direct effect) and prey availability (an indirect effect).

• Animal cells and systems
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• v.11 no.2
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• pp.105-115
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• 2007

Two species of the genus Xysticus from Korea are revised with detailed illustrations, spination of each leg, trichobothrium patterns and SEM photographs. The female of X. concretus Utochkin, 1968 is described for the first time and Xysticus lepnevae Utochkin, 1968 from Korea represent the species' southernmost known records. The latter species is distinguished by its male palpal organs with hooked median apophysis, developed ventral tibial apophysis and expanded retrolateral tibial apopysis, two tegular sutures and by it epigynum with triangular atrium and large copulatory ducts circled, with broadly transparent membrane. Furthermore, the Xysticus spiders, previously misidentified in Korea as male of X. dichotomus Paik, 1973 and female of X. bifurcus Paik, 1973 are in fact the true X. concretus.

• Animal Systematics, Evolution and Diversity
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• v.39 no.2
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• pp.72-76
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• 2023

The spider fauna of mountains, including national parks, in Korea was intensively surveyed in 2018-2019. During the seasonal surveys, males of Clubiona bakurovi Mikhailov, 1990 (family Clubionidae Wagner, 1887) and Otacilia ansula sp. nov. (family Phrurolithidae Banks, 1892) were collected from shrub foliage and leaf litter, respectively, in mountainous mixed forests. The males of Otacilia ansula sp. nov. can be easily distinguished from those of other its congeners by the slender and hook-shaped retrolateral tibial apophysis, ovoid distal tegular apophysis, and one dorsal spine on the femur with seven pairs of ventral spines on the tibia of leg I. This study provides descriptions of these two species with diagnosis, measurements, and morphological photographs.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.23 no.2
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• pp.161-167
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• 2009

Organic insulating materials which are utilized as insulating materials for the low voltage show unique carbonization characteristics when they are carbonized by a leakage current. Therefore the use of the carbonization characteristics makes it possible to examine the electrical fire which is caused by a leakage current flowing on the surface of the organic insulating material. In order to understand such carbonization characteristics, in this paper, experiments have been done to carbonize typical organic insulating materials such as phenol resin, PVC, and acrylic resin, and the carbonization patterns and the IR absorption spectrum of specimens have been analyzed. According to the analysis of the carbonization patterns, the phenol resin shows the so-called 'spider-leg' carbonization pattern due to a thermosetting property. In contrast to the phenol resin, the thermoplastic property makes it difficult to observe a clear carbonization pattern to verify carbonizing causes on the surfaces of PVC and acrylic resins. In this case, the IR absorption spectrum can be analyzed to examine the specimen carbonized by a leakage current. The analysis result shows that absorption peaks appear at the wave numbers of $3,400[cm^{-1}]$ and $1,618[cm^{-1}]$, which can be an important factor to verify the carbonizing causes.