• KIEAE Journal
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• v.11 no.4
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• pp.95-101
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• 2011

Earth has been used as a building material not only our country but also many foreign countries in the world. In foreign countries, we can often find the high-storied earthen houses which have been maintained for over several hundred years, which means the fact that earth differs in durability according to the methods of utilizing earth. So, the purpose of this study is to progress the fundamental research for utilizing earth as a wall material. Also, the another purpose of this study is to utilize the optimum micro-filler effect which adjusts the grain size of earth and the lime composite which promotes chemical combining power, and so examine whether earth material ensures its high compressive strength. This study applied both of rammed earth method and pour earth method among earth architecture methods. This study investigated compressive strength, slump, and air content according to unit binder weight. On the basis of such experimental results, this study derived the following conclusions. 1) Optimum micro-filler mixtures reduce a lot of fine particles contained in earth. If optimum micro-filler mixtures are used as aggregates, they develop lower W/B and relatively higher strength than general earth. 2) In this study, which uses optimum micro-filler earth mixtures and lime composite, rammed earth method develops 29MPa and pour earth method develops 28MPa in 28 days compressive strength. Such strengths can be utilized in building walls.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.30 no.2
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• pp.93-101
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• 2016

This paper presents the surface discharge characteristics in Dry-Air on laminated epoxy solid dielectrics and conductive particles in order to provide the valuable information for the insulation design of eco- friendly gas insulated switchgear. To improve insulation performance, the three types of the laminated epoxy solid dielectrics were proposed, and it was revealed that their surface discharge characteristics were similar to the bakelite dielectrics of same-laminated types. From the surface discharge characteristics of dry air, it was demonstrated that the effect of conductive particles on surface discharge voltage was dominant when there are this particles at the shortest electrode gap and that the degradation of insulation performance on the conductive particles was evident in epoxy than teflon. These phenomena were interpreted in terms of particle-triggered discharge mechanism and electric field of triple junction, respectively.

• Bulletin of the Korean Chemical Society
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• v.25 no.2
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• pp.271-279
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• 2004

The aroma component of Hallabong peel has been characterized by GC-MS with two different extraction techniques: solid-phase trapping solvent extraction (SPTE) and headspace solid-phase microextraction (HSSPME). Aroma components emitted from Hallabong peel were compared with those of other citrus varieties: lemon, orange and grapefruit by SPTE and GC-MS. d-Limonene (96.98%) in Hallabong was the main component, and relatively higher peaks of cis- ${\beta}$-ocimene, valencene and -farnesene were observed. Other volatile aromas, such as sabinene, isothujol and ${\delta}$-elemene were observed as small peaks. Also, principal components analysis was employed to distinguish citrus aromas based on their chromatographic data. For HSSPME, the fiber efficiency was evaluated by comparing the partition coefficient ($K_{gs}$Kgs) between the HS gaseous phase and HS-SPME fiber coating, and the relative concentration factors (CF) of the five characteristic compounds of the four citrus varieties. 50/30 ${\mu}$m DVB/CAR/PDMS fiber was verified as the best choice among the four fibers evaluated for all the samples.

• Journal of the Korea Concrete Institute
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• v.22 no.4
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• pp.567-574
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• 2010

As a eco-friendly material, Hwangtoh(red clay) has been studied for a partial or complete replacement of portland cement. Most of existing studies focused on the mechanical properties of the Hwangtoh concrete including the compressive strength, drying shrinkage, creep. In the present study, the flexural capacity of the beams made with the Hwangtoh concrete was tested. One of the concrete tested consisted of activated Hwangtoh replacing 20% of the cement. The other consisted 100% activated Hwangtoh replacing all the cement. The simple beams were tested under two point static loading. The flexural strength, cracking moment, deflection, and ductility were compared with those of the beams made with ordinary portland cement concrete.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2012.11a
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• pp.85-88
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• 2012

Lately, the scale of the primary energy consumption in Korea is ranked 10th in the world, and it takes up about 1.9% of the entire energy consumption in the world. And among total energy consumption in Korea, the ratio of the part corresponding to the residence or commercial buildings is about 30.5%. Also, with the increased interest in eco-friendly buildings, the production of eco-friendly building materials consisting of them also increases as well. However, since the process of their production generates much energy consumption, so this is being raised as a social problem. Therefore, this study suggests a method to improve thermal performance by using eco-friendly earth plastering materials and natural materials in order to reduce energy consumption in buildings. The experiment evaluated thermal performance by measuring the external and internal temperature of the curing after the plastering of 1cm in the wooden box of 30cm * 30cm * 30cm. As a result, there was difference in the order of powdered coal, pealite, chaff, and rice straw. Among them, powdered coal indicated excellent thermal performance. This will be the foundational research used to improve interior environment and reduce heating bills.

• Biomedical Science Letters
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• v.10 no.3
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• pp.211-217
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• 2004

For discrimination of ductal and ascinar cells, we isolated a single-chain variable domain fragment (scFv) antibody against ductal cells of salivary gland using phage display technique. From the spleen of a mouse immunized with ductal cell lysate, total RNA was prepared and used as a template for cDNA synthesis of antibody genes. The scFv genes were constructed with variable domain genes of heavy and light chain and were introduced into pCANTAB5E to construct phage scFv library. The phage particles specific for acinar cells were screened by subtraction using immunotubes coated with acinar and ductal cell lysate and enzyme-linked immunoabsorbance assay (ELISA). The characteristics of the scFv were determined by immunohistochemistry (IHC) and the result indicated that the isolated scFv has the specificity against ductal cells of salivary glands and tubules of kidney. And the scFv has an unique binding activity specific for Hashimoto's thyroiditis. The nucleotide sequence of isolated scFv gene was determined and revealed that V/sub H/ belongs to the mouse H-chain family subgroup IB and V/sub L/ to the mouse L-chain family subgroup III.

• Journal of Sericultural and Entomological Science
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• v.37 no.1
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• pp.10-15
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• 1995

Genetic characterization of Sri Lankan silkworm bivoltine population has not been at-tempted so far, since its sporadic introduction of bivoltine strains into the island, starting from the 1950's. Genetic structure of Sri Lankan population of mulberry silkworm Bombyx mori was investigated through estimation of general (GCA) and specific combining ability(SCA) and heritability(${h^2}_B$), on the economic quantitative characters from leading 8 inbreds and their 28 F1's in a half diallel cross, in an attempt to utilize the estimates in determination of future breeding methods and to predict the breeding value over the phenotypic value. It was found that the breeding population of the bivoltine silkworm in Sri Lanka has still maintained considerable amounts of additive gene action as well as nonadditive. For some time in the future, both breeding strategies of "selection without inbreeding" and also "inbreeding followed by crossing" should therefore be effective in genetic improvement of economic characters investigated. In addition, superior combiners in general and in specific F1′s were identified for each of 6 economic characters, to be immediately utilized in selection and also in cross breeding programs in Sri Lanka.

• Tribology and Lubricants
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• v.31 no.1
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• pp.28-34
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• 2015

This paper addresses the problems of using anti-freeze lubricants for different machines that must function at extremely low temperatures during winter operation in the Republic of Sakha (Yakutia). We discuss the possibility of obtaining anti-freeze base oils from Talakan crude oil, an area with major oil and gas deposits of the Republic of Sakha, and also provide the trade and technological classification of Talakan crude oil. We propose two different schemes for processing Talakan crude oil: the fuel scheme (obtaining light and heavy fractions as a fuel oil) and the base oil scheme (obtaining light fractions and base oils). We investigate the influence of pour point depressants on alkyl-methacrylate base on the low-temperature properties of the fractions obtained from Talakan crude oil and Korean base oils, and establish the optimal concentration of pour point depressants. We compare the properties of these fractions with the low-temperature properties of Korean base oils and find that the commercial oil "Ravenol 0W-40" provides optimistic results. We obtain oil with a pour point of minus $50^{\circ}C$ and a viscosity index greater than 100. The Design of Experiment was used to establish the optimum composition of the pour point depressants and the base oil S-8 to obtain lubricant oil with a kinematic viscosity of 17 cSt, viscosity index of 208, and a pour point of minus $64^{\circ}C$.

• Journal of Veterinary Clinics
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• v.26 no.4
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• pp.376-378
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• 2009

A surgery of penile translocation was performed on a seven-month-old male calf born in August 26, 2007. With a penis deviated, as to prevent proper coitus on a dairy farm, the calf would be introduced to the group of cows and heifers before sniffing around to detect which one is in heat and to indicate to a veterinarian the right time for artificial insemination or embryo transfer. This study showed how to make a teaser bull in his young age.

• Korean Journal of Veterinary Research
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• v.55 no.3
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• pp.155-161
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• 2015

The number of wild animal species is gradually decreasing due to poaching, hunting and habitat loss. While several endangered animal species have been successfully preserved at the zoo, assisted reproductive technology (ART) must be applied to restore wild animals. In the case of critically endangered animals, somatic cell cloning is considered the most appropriate method of ART. Somatic cell cloning can be beneficial for the reproduction of endangered species with limited female populations. However, gene and cell banks, and understanding of reproductive physiology and optimization of ART for wild animals are urgently required for further activation of artificial reproduction of endangered species, which enlarges its application and maintains biodiversity. Care should also be taken to consider ethical and legal issues associated with somatic cell cloning for conservation of endangered animals.