• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2002.05a
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• pp.169-176
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• 2002

Axial crushing behavior of cylindrical shell Is utilized in the braking of the high-velocity impacting object. In this paper, truncated cone shape brake device is introduced. That is, thickness of the shell is increased gradually from the impacting end to the other end. A detailed experimental investigation on the quasi-static axial crushing behavior of truncated cone type brake devices has been performed. Specimens of various shape were tested to check the influence of design parameters such as length, radius, mean thickness, and conical angle of cylinder. Influence of the material properties were also investigated by adopting aluminum, low carbon steel, and stainless steel as constructing materials. By analyzing deformation procedures of the specimens, it is seen that conical angle influence the deformation mode and the sequence of the wrinkles generation. Braking distance and mean braking force of each specimen were predicted based on the crushing load measured from the tests.

• Korean Journal of Veterinary Research
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• v.32 no.3
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• pp.309-319
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• 1992

This study was undertaken to establish the sequence of development of ages and its time of the fetal endochondral ossification in the scapula of the Korean native cattle. This study was also designed to confirm through histological observation the earliest stages of both chondrification and ossification. Thirty eight scapulae, a series of embryos and fetuses from the pregnant Korean native cattle ranging from 11 to 110mm in crown-rump (C-R) length, were used. The following results were obtained. The ossification center was observed in the supra- and infra- spinous fossa in the 5th group (CRL 51-60mm), that was markedly ossified in the 6th group (CRL 61~70mm) by Alizarin red S stain. The chondrogenic center of scapula was observed in the 1st group (CRL 11~20mm). The primary ossification center was presented in the 4th group (CRL 41~50mm). In the 5th group(CRL 51~60mm), the endochondral ossification progressed actively. Alcianophility was markedly increased in the interterritorial matrix in the 3rd group (CRL 31~40mm. However this reaction was markedly decreased in the interterritorial matrix the adjacent portion to the marrow cavity and trabecula in the 5th group (CRL 51~60mm).

• Journal of Microbiology
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• v.40 no.4
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• pp.254-259
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• 2002

The Phytophthora infestans requires two mating types for sexual reproduction. Amplified fragment length polymorphism (AFLP) was used to specifically detect different mating types of P. infestans. The AFLP primers E+AA (5'-GACTGCGTACCAATTCAA-3') and M+CAA (5'-GATGAGTCCTGAG-TAAC AA-3') detected a fragment that is specific in the A2 mating type of P. infestans. This fragment was cloned and sequenced. Based on the sequence data, PHYB-1 and PHYB-2 primer were designed to detect the A2 mating type of P. infestans. A single 347 bp segment was observed in the A2 mating type of P. infestans, but not in the A1 mating type of P. infestans or other Phytophthora spp. Identification of mating type was performed with phenotype (sexual reproduction) and genotype (CAPs marker) methods. Two factors, the annealing temperature and template DNA quantity, were investigated to determine the optimal conditions. Using mating type-specific primers, a unique band was obtained within annealing temperatures of 57$^{\circ}C$-62$^{\circ}C$ and DNA levels of 10pg-100 ng (data not shown).

• BMB Reports
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• v.29 no.2
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• pp.137-141
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• 1996

A partial cDNA encoding a Korean radish isoperoxidase was obtained from a cDNA library prepared from 9 day old radish root. In order to obtain Korean radish isoperoxidase cDNA, 5' RACE (rapid amplification cDNA end) PCR was performed and a cDNA (prxK1) encoding a complete structural protein was obtained by RT (reverse transcription)-PCR. Sequence analysis revealed that the length of the cDNA was 945 base pairs, and that of the mRNA transcript was ca. 1.6 kb. The deduced amino acid of the protein were composed of 315 amino acid residues and the protein was 92% homologous to turnip peroxidase, and 46% to 50% homologous to other known peroxidases. The 945 bp cDNA encoding Korean radish isoperoxidase was overexpressed in Escherichia coli up to approximately 9% of total cellular protein. The recombinant fusion protein exhibited 43 kDa on SDS-PAGE analysis and the activity level of the recombinant nonglycosylated protein was two fold higher in IPTG induced cell extracts than that of uninduced ones.

• Parasites, Hosts and Diseases
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• v.44 no.4 s.140
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• pp.313-320
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• 2006

In an effort to characterize, on the molecular scale, the Acanthamoeba initially isolated from the cornea of an amoebic keratitis patient associated with overnight-wear orthokeratology lens in Korea, we conducted mitochondrial DNA restriction fragment length polymorphism, 18S rDNA sequencing, and drug sensitivity analyses on the isolate (KA/PE1). The patient was treated with polyhexamethylene biguanide, chlorhexidine and oral itraconazole, which resulted in resolution of the patient's ocular inflammation. The majority of the molecular characteristics of the KA/PE1 were determined to be identical, or quite similar, to those of A. castellanii Ma strain, which had been isolated also from amoebic keratitis. The risk of Acanthamoeba keratitis as a potential complication of overnight orthokeratology is briefly discussed.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.12
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• pp.3688-3693
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• 2009

In this paper the design methode of a separated composition state machine based on the compositive map with connecting two chaotic maps together - sawtooth map $S_2(x)$ and tent map $T_2(x)$ and the result of that is proposed. this paper gives a graph of the chaotic states generated by the composition state machine using the compositive logic of two different chaotic maps - sawtooth map and tent map and also shows that the period of pseudo-random states has the length according to the precision of the discreet truth table.

• Journal of the Korean Society for Precision Engineering
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• v.14 no.3
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• pp.89-97
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• 1997

A genetic algorithm (GA) is a stochastic direct search strategy that mimics the process of genetic evolution. The GA applied herein works on a population of structural designs at any one time, and uses a structured information exchange based on the principles of natural selection and wurvival of the fittest to recombine the most desirable features of the designs over a sequence of generations until the process converges to a "maximum fitness" design. Principles of genetics are adapted into a search procedure for structural optimization. The methods consist of three genetics operations mainly named selection, cross- over and mutation. In this study, a method of finding the optimum topology of truss/beam structure is pro- posed by using the GA. In order to use GA in the optimum topology problem, chromosomes to FEM elements are assigned, and a penalty function is used to include constraints into fitness function. The results show that the GA has the potential to be an effective tool for the optimal design of structures accounting for sizing, geometrical and topological variables.variables.

• Korean Journal Plant Pathology
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• v.14 no.4
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• pp.350-357
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• 1998

A total of 12 strains of fluorescent Pseudomonas isolated from the cultivated mushrooms such as Agaricus bisporus and Pleurotus ostreatus were collected. They consisted of pathogenic Pseudomonas spp. and epiphytic Pseudomonas spp. of the cultivated mushroom. To analyze the phylogenetic relationship of these strains, ITS I region, the 16S-23S intergenic spacer region in the ribosomal RNA (rRNA) operon, was cloned and sequenced. The spacer regions of these strains were 495∼527 nucleotides in length and contained the genes encoding isoleucine-tRNA (tRNAIle) and alanine-tRNA (tRNAAla). The reciprocal homologies of each ITS I sequence among these strains were in the range of 84.2%∼98.8%. According to the analysis of ITS I sequences, the fluorescent Pseudomonas spp. were phylogenetically classified into three clusters. Cluster I consisted of Pseudomonas fluorescens, P. tolaasii, P. gingeri’, and P.‘reactans’(WLRO). Cluster II comprised Pseudomonas fluorescens biovar C and F. Cluster III composed P. agarici. Cluster I and II could be classified into P. fluorescens complex. P. agarici formed an independent taxon clearly separable from P. florescens complex.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.48 no.2
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• pp.13-19
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• 2016

Moso Bamboo was investigated as the a raw material for pulp and paper industry. Soda-Anthraquinone (Soda-AQ) pulping, elemental chlorine free bleaching was applied. Yield of soda or soda-AQ pulp was 29.3-31.7% with Kappa number 33.0-22.8 with different cooking time or anthraquinone addition at 20% active alkali. In soda or soda-AQ pulping, 81-86% of xylan was removed, which was the main reason for lower pulp yield than hardwood species. Average fiber length of Moso Bamboo soda-AQ pulp was 1.36 mm with $15.5{\mu}m$ fiber width. Soda-AQ pulp from Moso Bamboo (P-3, lowest Kappa pulp) was bleached with 5.5-6.5% of chlorine dioxide charge as D0ED1 bleaching sequence. In 3-stages ECF bleaching, final brightness of 85.3% ISO was achieved with total chlorine dioxide 6.5%.

• Journal of Microbiology and Biotechnology
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• v.8 no.6
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• pp.663-668
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• 1998

Several neurodegenerative diseases such as Huntington's disease, dentatorubralpallidoluysian atrophy, spinobulbar muscular atrophy, Machado-Joseph disease, and spinocerebellar ataxias type 1 are associated with the aggregation of expanded glutamine repeats within their proteins. Generally, in clinically affected individuals, the expansion of the polyglutamine sequences is beyond 40 residues. To address the length of polyglutamine that forms aggregation, we have constructed plasmids encoding glutathione S-transferase (GST) Machado-Joseph disease gene fusion proteins containing polyglutamine and investigated the formation of aggregates in E. coli. Surprisingly, even $(Gin)_8$, in the normal range as well as $(Gin)_{65}$ in the pathogenic range enhanced the formation of insoluble protein aggregates, whereas $(Ser)_8$, and $(Aia)_8$, did not form aggregates. Our results indicate that the formation of protein aggregates in GST-polyglutamine proteins is specifically mediated by the polyglutamine repeat sequence within their protein structure. Our study may contribute to the understanding of the molecular mechanism of the formation of protein aggregates in neurodegenerative disorders and the development of preventative strategies.