• Journal of Microbiology
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• v.44 no.1
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• pp.77-82
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• 2006

The tea looper caterpillar, Ectropis obliqua, is one of the major pests of tea bushes. E. obliqua single-nucleocapsid nucleopolyhedrovirus (EcobSNPV) has been used as a commercial pesticide for biocontrol of this insect. However only limited genetic analysis for this important virus has been done up to now. EcobSNPV was characterized in this study. Electron microscopy analysis of the occlusion body showed polyhedra of 0.7 to $1.7\;{\mu}m$ in diameter containing a single nucleocapsid per envelope of the virion. A 15.5 kb genomic fragment containing EcoRI-L, EcoRI-N and HindIII-F fragments, was sequenced. Analysis of the sequence revealed that the fragment contained eleven potential open reading frames (ORFs): lef-1, egt, 38.7k, rrl, polyhedrin, orfl629, pk-1, hoar and homologues to Spodoptera exigua multicapsid NPV (SeMNPV) ORFs 15, 28, and 29. Gene arrangement and phylogeny analysis suggest that EcobSNPV is closely related to the previously described Group II NPV. Bioassays on lethal concentration $(LC_{50}\;and\;LC_{90})$ and lethal time $(LT_{50}\;and\;LT({90})$ were conducted to test the susceptibility of E. obliqua larvae to the virus.

• Journal of the Korean Society for Precision Engineering
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• v.25 no.3
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• pp.56-62
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• 2008

The biocompatibility and the fatigue strength of Co-Cr-Mo alloy are excellent, so it is used well for the material of artificial joints. The head of artificial joint needs mirror surface for reduction of abrasive resistance. Mirror finishing of Co-Cr-Mo alloy with geometrically defined single crystal diamond cutting tools is handicapped by micro chipping of tool edge. In general, it is said that the micro chipping of diamond tool is caused by work hardening of Co-Cr-Mo alloy for the cut. In the present research, mirror finishing of Co-Cr-Mo alloy by applying ultrasonic elliptical vibration cutting was carried out. The experimental results show that the micro chipping of diamond tool was suppressed and the tool wear was remarkably reduced as compared with the ordinary diamond cutting without elliptical vibration motion. It was confirmed that the good mirror surface of maximum surface roughness of 25 nmP-V was obtained for the cutting length of about 14 m. It is expected that mirror finishing of Co-Cr-Mo alloy can be achieved by applying ultrasonic elliptical vibration cutting practically.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.61 no.3
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• pp.413-421
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• 2012

This paper proposes the design and implementation of fluid flow generation system by using polypropylene(PP) water capture, which harvests electric energy from the kinetic energy of tidal current or water flow and drives the desired load, and applies it to the discharge drain of Hadong thermal power plant. This experimental system is composed of water captures, driving wheel, gear trains, 10[kW] synchronous generator, and three phase rectifying circuit which drives lamp load for test. The proposed water capturing system which is composed of water captures, rope and driving wheel, rotates as caterpillar according to water flow. This system is very easy to manufacture and more economical than another type of tidal current turbines such as conventional propeller and helical type. Also, we estimated the available fluid flow energy that can be extracted from the cooling water in discharge drain based on drain's cross-sectional area. Therefore, this paper confirms the validity of proposed fluid flow generation system with water captures and the possibility of its application for renewable energy generation in discharge drain of thermal power plant, from the obtained performance characteristic of this energy conversion system.

• Journal of The Korean Association For Science Education
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• v.13 no.3
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• pp.327-333
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• 1993

The purpose of this study was to investigate children's ideas about growth of plants and their conceptural change after instruction to apply SPACE (Science Processes And Concepts Exploration) Learning strategy. For this study, a total of 55 students from infants to 5th grade were sampled. Data were obtained by the individual interview procedure and summarized by using network analysis. The major results of this study were as follows : 1. A very small number of students responded reforming or reorganisation of materials about the mechanism of germination and growth inside the seeds. 2. Almost all students confused between conditions necessary for germination and growth. Water and sunlight were mentioned by many students, while air and temperature were mentioned by a few students as the condition. 3. Some of the students showed that growth occurs continuously. Many students explaned occurence of growth about Plants related to the night, monning, or evening. 4. With the explaning about the necessary conditions for caterpillar growth, students mentioned conditions related in terms of human experience. 5. Many young childrens showed tendency of the egocentric and human-centered view of the world. Students scientific concepts increased significantly with age. Many students conceptions depend on the context-specificity ideas.

• Journal of Microbiology and Biotechnology
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• v.17 no.4
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• pp.632-637
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• 2007

A cytoplasmic polyhedrosis virus (CPV) was isolated from the larvae of Thaumetopoea pityocampa and shown to cause an infection of midgut cells. This viral infection revealed several important diagnostic symptoms, including discoloration of the posterior midgut, reduced feeding, and extended development time of the larvae. The virus infection is lethal to Thaumetopoea pityocampa, and with the increasing doses kills the larvae within 4-5 days post infection. Electron microscopy studies showed typical cytoplasmic polyhedral inclusion bodies that are icosahedral, and ranged from 2.4 to $5.3{\mu}m$ in diameter. Electrophoretic analysis of the RNA genome showed that the virus has a genome composed of 10 equimolar RNA segments with the sizes of 3,907, 3,716, 3,628, 3,249, 2,726, 1,914, 1,815, 1,256, 1,058, and 899 bp, respectively. Based on morphology and nucleic acid analysis, this virus was named Thaumetopoea pityocampa cytoplasmic polyhedrosis virus (TpCPV), and belongs to the genus Cypovirus, family Reoviridae.

• The Journal of Korea Robotics Society
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• v.12 no.1
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• pp.65-77
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• 2017

In this paper, we introduce the pipe cleaning robot developed to clean the gas impurities of the iron manufacturing equipments. The pipe cleaning robot is composed of two driving modules and one cleaning module. 2-DOF joint units were developed for connections among the modules. To maximize the traction power of the driving parts, it became caterpillar type. The extension links have been developed to maintain the traction force in case the pipe inner diameters change. Three cleaning modules were developed for the effective cleaning in the pipe. The driving and cleaning performance tests of the pipe cleaning robot were proceeded in the field of the iron manufacturing equipments.

• Microbiology and Biotechnology Letters
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• v.38 no.2
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• pp.117-123
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• 2010

BT toxin is produced by a soil bacterium Bacillus thuringiensis and has long been used as a biological insecticide without any competition. Recently, Photorhabdus, a symbiotic bacterium from entomopathogenic nematodes, family Heterorhabditae, has been researched and discussed as alternatives to B. thuringiensis. Photorhabdus, which lives in the gut of entomopathogenic nematodes, is a highly virulent pathogen of a wide range of insect larvae. When an insect is infected by the nematodes, the bacteria are released into the cadaver, and produce a number of insecticidal toxins. The biological role of the different Photorhabdus toxins in the infection process is still unclear. Photorhabdus toxin complex (Tc) is highly secreted gut-active toxin and has been characterized as a potent three-component (A, B and C) insecticidal protein complex. These components are necessary for full oral activity against insect larvae. The Photorhabdus PirAB binary toxins exhibit a potent injectable activity for Galleria mellonella larvae, and have oral toxicity against mosquitoes and caterpillar pest Plutella xylostella. Other toxin, 'makes caterpillars floppy' (Mcf) showed injectable activity on caterpillars. Recombinant Mcf triggers apoptosis in both insect hemocytes and the midgut epithelium and carries a BH3 domain. In this review, the relationship between the Photorhabdus and the nematode is discussed and recent important insecticidal toxins from Photorhabdus are described.

• International Journal of Industrial Entomology and Biomaterials
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• v.12 no.1
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• pp.1-5
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• 2006

Cordyceps, one of the well-known traditional Chinese medicines, consists of the dried fungus C. sinensis growing on the larva of caterpillar. It is commonly used as a tonic of restoring vital body functions. In order to evaluate the pharmacological effects of C. militaris, the anti-oxidation and antiaging effect of cultured C. militaris growing on pupa of silkworm Bombyx mori, were investigated. The results showed! that the contents of lipofusin in myocardium were reduced and the SOD activity in the liver were elevated in a dose-dependent manner while no effect was observed for blood GSH-Px activity and liver MDA content in mice perfused with the cultured C. militaris compared to those untreated mice. Furthermore, the average life span, maximum life span and 50% death time of the fruit flies treated with cultured C. militaris were markedly prolonged. The results suggest that the cultured C. militaris growing on pupa of silkworm possesses anti-oxidation and delay senescence activity.

• Tribology and Lubricants
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• v.38 no.4
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• pp.143-151
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• 2022

This study analyzes patents related to oil diagnosis of construction equipment. Oil diagnosis is extremely important for maintaining construction equipment properly. Through the evaluation of existing patents, a patent strategy for the future construction equipment market is presented. The related patents are classified and selected in several steps. Finally, 16 valid patents are selected and analyzed in detail. In the classification process, patents are classified by country, year, and company. A market analysis shows that the top 10 companies have a market share of more than 50. In addition to patents related to the oil analysis of construction equipment, patents related to automobile oil analysis and development of oil sensors are investigated to identify the contents of patents in other fields that can be applied to oil diagnosis technology for construction equipment. Moreover, not only the contents of research articles of two Korean construction companies, but also the research trends in the literature in this field are used in the analysis. The related patents of the two Korean companies are few. Companies with a high market share, including Caterpillar, hold many patents, and patents for diagnosis algorithms using such technologies as artificial intelligence and artificial neural networks, along with oil sensor-based condition monitoring technology, are gradually expanding.

• Mycobiology
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• v.40 no.2
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• pp.100-106
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• 2012

Interest in commercial cultivation and product development of Cordyceps species has shown a recent increase. Due to its biochemical and pharmacological effects, Cordyceps militaris, commonly known as orange caterpillar fungus, is being investigated with great interest. Cultivation of C. militaris has been practiced on a large scale in order to fulfill a demand for scientific investigation and product development. Isolates of C. militaris can be easily established from both spores and tissue. For isolation of spores, ascospores released from mature stromata are trapped in sterile medium. Multi-ascospore isolates, as well as combinations of single ascospore strains, are used for production of fruiting bodies. Progeny ascospore strains can be isolated from artificial fruiting bodies, thus, the cycle of fruiting body production can be continued for a long period of time. In this study, we examined fruiting body production from multi-ascospore isolates and their progeny strains for three generations. $F_1$ progeny strains generally produced a larger number of fruiting bodies, compared with their mother multi-ascospore isolates; however, $F_2$ and $F_3$ progeny strains produced fewer fruiting bodies. Optimum preservation conditions could help to increase the vitality of the progeny strains. In order to retain the fruiting ability of the strains, further testing of various methods of preservation and different methods for isolation should be performed.