• Proceedings of the Korean Society of Veterinary Pathology Conference
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• 2003.10a
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• pp.41-41
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• 2003

White spot syndrome virus (WSSV) is the causative agent of a disease that has led to severe mortalities of cultured shrimps in Korea and many other countries. Since 1993, massive mortalities due to the viral infection have also occurred in the penaeid shrimps cultured in Korea. WSSV is a large, circular, double stranded (ds) DNA virus and an enveloped, ellipsoid virus with a rod-shaped nucleocapsid with flat ends. In order to identify the characteristics of this Korean isolate of WSSV, the genes for four virion proteins, VP15, VP19, VP28 and VP35 were cloned and their sequences were compared with the available pool of WSSV gene sequences in the GenBank/EMBL databases. From these comparisons, we confirm the occurrence of WSSV in Korea and deduce that, VP15, VP28 and VP35 genes are identically conserved among the Korean isolate and geographically different foreign isolates, but VP19 amino acid sequences of the Korean WSSV isolates changed valine of the foreign isolates into aspartate. (omitted)

• Journal of Korean Society of Forest Science
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• v.6 no.1
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• pp.6-10
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• 1967

In the present paper author investigated the symptom, pathogenic fungus and pathogenicity of Endothia canker of Carpinus laxiflora in Korea, and made clear the indistinct discription on its pathogen in the past. 1. The pathogen is identified as Endothia fluens (Schw.) Shear et Stevens. The discription is recorded as follows: Stromata cortical, erumpent, spherical or conical, outer yellowish-brown and inner yellowish, 0.5 to 2.5 mm in diameter; perithecia irregularly embeded in the bottom of stroma, 7 to 23 in a stroma usually spherical to elliptical or irregular, 235 to $370{\mu}$ in diameter, with black slender necks; each neck open the papilliate ostiole to the surface, about 250 to $400{\mu}$ in length; asci clavate or fusoid, colorless, 31.16 to 42.64 by 6.54 to $8.20{\mu}$ in size, average 37.02 by $6.84{\mu}$, with 8 ascospores in double line; ascospores elliptical, ovate or cylindrical, with rounded ends, hyaline, 1-septate, not constrict at the septum, 6.51 to 9.30 by 3.16 to $3.72{\mu}$, average 7.61 by $3.44{\mu}$ in size; pycnidia formed abundantly in stroma. spherical at first but later irregular large cavity by fussing each other; pycnospores oblong or rod-shaped, hyaline, non-septate, 3.8 by $1.9{\mu}$ in size; spore-horn formed abundantly under moist condition. 2. The pathogen is wound parasite invading the hosts through the wound. But after the infection is established, expanding the disease lesion is swiftly vigorus.

• Progress in Superconductivity and Cryogenics
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• v.8 no.1
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• pp.19-22
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• 2006

Desirable substrates for $YBa_2Cu_3O_{7-\delta}$ coated conductor are highly cube textured Ni or Ni-alloy tapes, which can be produced by cold rolling and recrystallization annealing. We have fabricated hi-axially textured pure Ni tapes for the application of coated conductors. The sintered Ni rod was cold-rolled into the thin tapes of $50{\mu}m$ thickness and the tapes were heat-treated for texture development with line-focused infrared heater. The temperature was maintained at $800\sim1050^{\circ}C$, using 1kW double ended linear halogen lamp in $96%Ar-4%H_2$ atmosphere The biaxially tortured Ni tapes were successfully formed by line-focused infrared heat treatment The texture of the annealed Ni tapes was analysed using the GADDS (general area detector diffraction system). The full width at half maximum values of phi and omega scan for the Ni tapes were less than $10^{\circ}$ and the grain size was $20-50{\mu}m$.

• Journal of the Korean Geotechnical Society
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• v.22 no.12
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• pp.25-31
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• 2006

This paper studies the field applicability of the Special Chemical grouting Method (SCM) in reinforcing and reducing permeability of the back of an existing continuous wall. SCM uses double rod which imposes intermediate pressure ($981{\sim}9,810kPa$) to disturb, cut, discharge, and mix the ground. It is observed that a bulb is formed by using cement paste and environmentally friendly injection materials with minimal alkali leaching. Uniaxial compression tests, test for chemical properties and fish poison test are performed. Test results indicate that the method results in higher durability, less leaching through the use of the environmentally friendly injection material and faster mobilization of the strength. In addition, field tests confirm the formation of the bulb and the seepage cutoff wall.

• Journal of Aerospace System Engineering
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• v.16 no.5
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• pp.62-69
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• 2022

EHA (Electro-Hydrostatic Actuator) is more energy efficiency than a centralized hydraulic system. In particular, the EHA used for aircraft has a redundant design in preparation for failure scenario. Also, due to the aircraft's internal space limitation, the actuator's length must be optimized. Therefore, a series configuration of double rod and single rod cylinder is advantageous. However, due to the asymmetry of the cross-sectional area of the piston, the force fighting phenomenon between the two cylinder areas occurs during redundant operation with a general control system. In this paper, the force fighting phenomenon of redundant EHA was simulated. A controller with load compensation and a force control-based position controller as a method to suppress its stimulation

• Korean journal of applied entomology
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• v.15 no.3 s.28
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• pp.137-145
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• 1976

Orchids have been propagated vegetatively for a long time without adequate control measures against virus diseases in Korea. As a result, it is presumed that most of the orchid varieties in Korea may have been degenerated. Nevertheless there has been little work on the virus diseases of orchids in Korea. Therefore studies were initiated to isolate an4 characterize the orchid viruses occurring in Korea. The results obtained are summerized as follows. 1. Symptoms of virus diseases on orchid varieties can be grouped 1) mosaic, 2) necrotic streak with mosaic, 3) ring necrosis, 4) chlorotkc ring and 5) necrotic spot. 2. A total of 102 orchid plants representing 4 genera were investigated on the occurrence of Cymbidium mosaic virus and tobacco mosaic virus by serological agar-gel double diffusion test. The test revealed that approximately $45\%$ of the orchids were infected with Cymbidium mosaic virus. None of the plants were found to be infected with tobacco mosaic virus. 3. Local lesions appeared on the inoculated leaves of Chenopodium amaranticolor Cassia occidentalis and Datura stramonium 7-12 days after mechanical inoculation with Cymbidium mosaic virus. 4. Physical properties of the Cymbidium mosaic virus determined by inoculation on Chenopodium amaranticolor were as follows: Thermal inactivation Point; $75-80^{\circ}C$, dilution end Point; $10^{-5}-10^{-6}\%$ aging in vitro; 8 days. 5. Three different buffers at pH 7.0 and pH 9.0 were compared for the efficiency of agar-gel double diffusion test with Cymbidium mosaic virus. Phosphate, imidazol and tris buffer at pH 7.0 gave equally satisfactory results. 6. Electron microscopic examination of the Cymbidium mosaic virus revealed rod shaped particles measuring 460-580mu.

• Parasites, Hosts and Diseases
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• v.45 no.1 s.141
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• pp.1-9
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• 2007

The endosymbionts of 4 strains of Acanthamoeba(KA/E9, KA/E21, KA/E22, and KA/E23) isolated from the infected corneas of Korean patients were characterized via orcein stain, transmission electron microscopic examination, and 16S rDNA sequence analysis. Double membrane-bound, rod-shaped endosymbionts were distributed randomly throughout both the trophozoites and cysts of each of Acanthamoeba isolates. The endosymbionts of KA/E9, KA/E22, and KA/E23 were surrounded by electron-translucent areas. No lacunae-like structures were observed in the endosymbionts of KA/E21, the bacterial cell walls of which were studded with host ribosomes. Comparative analyses of the 16S rDNA sequences showed that the endosymbionts of KA/E9, KA/E22 and KA/E23 were closely related to Caedibacter caryophilus, whereas the KA/E21 endosymbiont was assigned to the Cytophaga-Flavobacterium-Bacteroides(CFB) phylum. In the 4 strains of Acanthamoeba, the hosts of the endosymbionts were identified as belonging to the Acanthamoeba castellanii complex, which corresponds to the T4 genotype. Acanthamoeba KA/E21 evidenced characteristics almost identical to those of KA/E6, with the exception of the existence of endosymbionts. The discovery of these endosymbionts from Acanthamoeba may prove essential to future studies focusing on interactions between the endosymbionts and the amoebic hosts.

• Geotechnical Engineering
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• v.12 no.4
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• pp.33-46
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• 1996

When structures are constructed in ground with poor bearing capacity, deformation of ground may induce foundation settlements and cracks of structures. Recently, high pressure jet grouting is widely used to improve the engineering properties of such foundation. Sometimes, the grouting columns are built in the ground by jet grouting method. They are used as in -situ piles to increase the bearing capacity of existing foundation. In this paper, as for the grouting columns built in ground by high pressure jet grouting with double tube rod, the effects on reinforcement and bearing capacity of ground are investigated. A series of laboratory tests has been performed on the specimens sampled from the grouting columns and a pile load test has been performed on a grouting column. The test results show that high pressure jet grouting has a sufficient effect on reinforcement of ground and restraint of settlement of structure.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2012.04a
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• pp.911-916
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• 2012

It is important to identify dynamic characteristics of nuclear fuel components. Since the fuel always exposed to turbulent flow, the dynamic contact between grids and rods is one of the fuel failure modes. The dynamic behavior of grids in nuclear fuels is quite complex, since two pairs of spring support are placed in the limited space. The strap in a cell has single spring and double dimples and this paper focuses on investigation of the grid strap(Test Fuel Strap, TFS) vibration in one cell. To identify the grid strap vibration, modal analysis of the strap is performed using Finite Element Method (FEM). Modal testing on a $5{\times}5$ grid structure without rods is performed. The modal testing results are compared to analytic results. In addition, random test considering rod effect is performed about a $5{\times}5$ grid with rods under real contact condition in the air. Finally, the strap vibration of a $5{\times}5$ fuel bundle in INvestigation of Flow INduced vIbraTion(INFINIT) facility is measured in real fluid velocity condition without heating. It is shown that modal frequencies from the test are almost equal to those peak frequencies in the INFINIT test.

• Korean Journal of Ichthyology
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• v.20 no.2
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• pp.97-104
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• 2008

Comparative study of retinal structure in two Korean endemic freshwater fishes, Zacco koreanus and Pseudobagrus koreanus, was carried out by light and scanning electron microscopy. In the visual cell layer comprised of cone cells and rod cells, the cone cells showed a distinct difference between both species. Z. koreanus had two types of cone cells, single cone cells including a long single and short single cone cells, and double cone cells, whereas P. koreanus had only one type of single cone cells having no its short single and long single cones. Meanwhile, the cone cells of Z. koreanus were arranged in more compact-rowed pattern, but it was more loose and irregular in P. koreanus. Based on field observation, Z. koreanus is mainly a epipelagic or sometimes benthopelagic and a diurnal fish with a round and large eye, while P. koreanus is a demersal and nocturnal fish with an oval and small eye. Therefore, the difference in the retinal structure of two species seems to be closely related to their ecological habitats.