• 대한전기학회논문지:전기물성ㆍ응용부문C
• /
• 제55권11호
• /
• pp.532-537
• /
• 2006

Lightning induced faults accounts for more than 66% at the transmission lines of KEPCO. The lightning causes damages to power system equipments including transmission line, the blackout of electricity and the electro-magnetic interference. Because of this reason, we need the real time lightning information for the optimal operation of power system. And, it is required to obtain and accumulate the lightning current parameters for the insulation design. In 2005, KEPRI constructed a lightning detection network, the KLDNet (i.e. Kepco Lightning Detection & Information System) and launched a lightning information service for KEPCO customers. It is intended to provide data service on the operation of transmission lines and collect lightning-related data, which is the most important factor regulating power system design and operation. The new system will replace LPATS, the old detection system, which has been operating since 1995 and is rapidly failing in terms of both detection performance and location accuracy. The purpose of this paper is to explain the work performed and the results of that work in performing a site survey of several locations. The purpose of the site survey is to find locations acceptable for the installation of a lightning location receiver in support of a Lightning detection system(LDS). A restriction was placed on the surveyed locations, as they must belong to the Korea Electric Power Company. This requirement was made to facilitate the communication needs of the LDS network. Total of 15 sites were evaluated as possible LDS sensor sites. Some of the sites were rejected for physical reasons and therefore no electrical testing was performed. Of the 15 sites, total of 10 sites were considered acceptable and 5 sites were rejected for various reason. In this paper, we would like to explain the site survey and detection efficiency for LDS.

• Korean Chemical Engineering Research
• /
• 제58권4호
• /
• pp.658-664
• /
• 2020

Zeolite HY is wet impregnated with Ni (0.1, 0.3, 0.4, 0.5 wt%), Pt (0.1 wt%) and reduced in presence of hydrogen to form nanosized particles of Ni and Pt. All the catalysts were characterized by XRD, TEM, ESCA, NH₃-TPD, Pyridine adsorbed FT-IR and BET. Characterization results confirm that the Ni and Pt fractions effectively rehabilitated the physio-chemical properties of the zeolite HY catalysts. Further, all the reduced catalyst were screened with hydroisomerization of m-xylene at LHSV = 2.0 h^-1 in the temperature range 250-400 ℃ in steps of 50 ℃ in hydrogen atmosphere (20 ml/g). The addition of Ni to Pt catalyst increases hydroisomerization conversion, as well as maximizes p-xylene selectivity by restricting the pore size. The increasing trend in activity continues up to 0.3 wt% of Ni and 0.1 wt% Pt addition over zeolite HY. The increasing addition of Ni increases the total number of active metallic sites to exposed, which increases the metallic sites/acid sites ratio towards the optimum value for these reactions by better balance of synergic effect for stable activity. The rate of deactivation is pronounced on monometallic catalysts. The results confirm the threshold Ni addition is highly suitable for hydroisomerization reaction for product selectivity over Ni-Pt bimetallic/support catalysts.

• 대한의생명과학회지
• /
• 제19권4호
• /
• pp.310-314
• /
• 2013

CYP2E1 in the liver has been studied intensively because it is involved in the metabolic activation of xenobiotics. It is inducible by alcohol, so it has been suspected as the cause of cancer in the stomach and lung. The possible role of CYP2E1 has been suggested strongly as causing tissue damage in mice with renal failure. It was also suspected that 5'-flanking region of CYP2E1 gene might be involved with renal failure. So, we investigated polymorphism of restriction enzyme sites within CYP2E1 gene using the PCR-RFLP analysis. PstI and RsaI sites were located at 5'-flanking region and DraI site was located at intron 6. All three types (W/W, W/S, S/S) were observed for these enzymes although each incidence was somewhat different depending the enzyme sites. W/W was prominent for PstI whereas W/S was markedly high for RsaI. Overall, polymorphic incidence in patients was somewhat higher than normal population. This research should facilitate further investigation of CYP2E1 at genetic level as the direct cause of tissue damage in various organs.

• 미생물학회지
• /
• 제24권4호
• /
• pp.341-351
• /
• 1986

항생제에 대하여 다중 저항성을 갖는 Shaphylococcus aµreus D-H-1으로부터 chloram phenicol(Cm) 저항성 유전자를 가진것으로 확인된 R-plasmid(pSBK203, 2.5MdaJ.)를 분리하여 Bacillus subtilis BD 170 내에셔 발현시켰으며 이 Cm 저항성 유전자를 cloning하기 위하여 pSBK203상의 제한효소 인식부위를 결정하였다. pSBK203 상의 TaqI 부분 절편 0.3 kb을 pBD9 CZaI 인식부위내에 삽입하여 얻은 재조합 plasmid(pTQ16)와 TaqI부 분절편과 O.lkb 엇갈럼이 있는 RsaI 단일절떤(1. 3 kb} pBR322의 Seal 인식부위에 삽입하여 얻은 재조합 p plasmid(pHW20)에서 Cm 저항성이 획득되었다. pBD9 및 pBR322 상에 삽입된 두 절펀내에 Hinf, Taq I 빛 BglII의 제한효소 인식부위가 존재하였으며 이들 중 행III 인식부위에 의하여 Cm 저항성이 불활성 되었다.

• Asian-Australasian Journal of Animal Sciences
• /
• 제19권8호
• /
• pp.1079-1084
• /
• 2006

To determine whether a link exists between reproductive seasonality and the structure of the melatonin receptor 1A (MTNR1A) gene, the latter was studied in nonseasonal estrous breeds (Small Tail Han and Hu ewes) and seasonal estrous breeds (Dorset, Suffolk and German Mutton Merino ewes). A large fragment of the exon 2 of the MTNR1A gene was amplified and a uniform fragment of 824 bp was obtained in 239 ewes of five breeds. The 824 bp PCR product was digested with restriction endonucleases Mnl I and Rsa I, and checked for the presence of restriction sites. The presence (allele M) or absence (allele m) of an Mnl I site at base position 605 led to three genotypes MM (236 bp/236 bp), Mm (236 bp/303 bp) and mm (303 bp/303 bp) in five sheep breeds. The presence (allele R) or absence (allele r) of a Rsa I site at base position 604 led to three genotypes RR (267 bp/267 bp), Rr (267 bp/290 bp) and rr (290 bp/290 bp) in five sheep breeds. Frequencies of MM and RR genotypes were obviously higher, and frequencies of mm and rr genotypes were obviously lower in nonseasonal estrous sheep breeds than in seasonal estrous sheep breeds. Sequencing revealed four mutations (G453T, G612A, G706A, C891T) in mm genotype compared to MM genotype and one mutation (C606T) in rr genotype compared to RR genotype. For polymorphic Mnl I and Rsa I cleavage sites, the differences of genotype distributions were very highly significant (p<0.01) between Small Tail Han ewes and seasonal estrous sheep breeds. In each group, no significant difference (p>0.05) was detected. These results preliminarily showed an association between MM, RR genotypes and nonseasonal estrus in ewes and an association between mm, rr genotypes and seasonal estrus in ewes.

• Archives of Pharmacal Research
• /
• 제29권1호
• /
• pp.88-95
• /
• 2006

Analysis of molecular nature of mitochondrial DNA (mtDNA) could be powerful marker for anthropological studies of modern populations. While population genetic studies on mtDNA have been reported for several ethnic groups, no such study has been documented for the Korean population. We surveyed mtDNA polymorphisms in the HVS I of noncoding D-loop region and its upstream region from 430 unrelated healthy Korean population by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and direct sequencing analysis. PCR product with 2,790 bp spanning the specific mtDNA region (mt13715-16504) was subjected to RFLP analysis using 6 restriction enzyme (Hinf I, Hae III, Alu I, Dde I, Mbo I, Rsa I). On the PAUP analysis of PCR-RFLP results, 38 mtDNA haplotypes (Hap 1-38) were detected in the Korean populations, which were classified into 11 haplogroups (Grp 1-11) of related haplotypes encompassing all 38 haplotypes. In comparison of sequencing data with Anderson's reference sequence, the transition type was more prevalent than the transversion type. Insertions or deletions were not found. In addition, three of the polymorphic sites (A16240C, A16351G, G16384A) in HVS-I region are determined newly. The polymorphic sites were distributed randomly in the region, though the frequency at each site was variable. Thus, this research might be required for the genealogical study of Orientals.

• 한국미생물·생명공학회지
• /
• 제23권5호
• /
• pp.536-543
• /
• 1995

Multicopy integration vector is a very useful vector system in that they can be integrated into chromosomal DNA in several copies and stably maintained under non-selective conditions. To develop a multicopy integration vector system in the yeast Yarrowia lipolytica, P-type ribosomal DNA was cloned from Y lipolytica. A HindIII-BglII fragment of the cloned rDNA and a promoterless URA3 gene were inserted into pGEM1, generating multicopy integration vectors, pMIYL-1 and pMIYL-2. The rDNA fragment is for targeted homologous recombination between the vector and the chromosomal DNA of Y. lipolytica, and the promoterless URA3 gene is a defective selection marker for inducing multicopy integration. pMIYL-1 and pMIYL-2 have an unique restriction enzyme site, KpnI, and two unique restriction enzyme sites, KpnI and EcoRI, repectively, which can be used for targeting of the vectors into the rDNA of Y. lipolytica chromosomal DNA. After transformation of the vectors into Y. lipolytica, copy number and stability were analyzed by Southern hybridization. The vectors were found to be present in less than 5 copies per cell and were stably maintained during growth in non-selective media.

• Journal of Ecology and Environment
• /
• 제29권2호
• /
• pp.143-149
• /
• 2006

This study was conducted to identify native ectomycorrhizal (ECM) fungi colonizing Pinus densiflora for revegetation of abandoned coal mines in Korea. Seedlings of P. densiflora growing on coal mining spoils of a study site in Samcheok were collected. ECM roots were observed under stereomicroscope and their DNA were extracted from each root tip for a seedling for molecular identification. A PCR primer pair specific to fungi, ITS1F and ITS4, was used to amplify fungal DNA. Restriction enzymes, Alul and Hinfl were used for restriction fragment length polymorphism (RFLP). Combined with RFLP profiles and sequence analysis, total twenty one taxa were identified from the ECM root tips. Basidiomycetous fungi including Thelephoraceae, Pezizales, Laccaria, Pisolithus and Ascomycetous fungi including ericoid mycorrhizal fungi were identified from this study. Results showed that the most frequently found in the study sites was a species in Thelephoraceae. A possible use of ECM fungi identified in this study for the revegetation of abandoned coal mines with P. densiflora was discussed.

• Journal of Microbiology
• /
• 제34권4호
• /
• pp.334-340
• /
• 1996

The enzyme, cis,cis-muconate lactonizing enzyme has been proposed to play a key role in the $\beta$-ketoadipate pathway of benzoate degradation. A 3.2-kb EcoRI fragment termed as pRSU2, isolated from a Pseudomonas cepacia genomic library was able to complement the catB defective mutant. Several relevant restriction enzyme sites were determined within the cloned fragment. In Pseudomonas putida SUC2 carrying pRSU2, the enzyme activity was relatively higher than those of the induced or partially induced state of wild type P. putida PRS2000. It was probably due to higher expression of P. cepacia catB in P. putida PRS2000. It was probably due to higher expression of P. cepacia catB in P. putida. One possible interpretation of these results is that the catB promoter in P. cepacia is recognized within P. putida, resulting in the almost same expression level.

• 한국식물병리학회지
• /
• 제11권1호
• /
• pp.66-72
• /
• 1995

The coat protein (CP) gene of cucumber mosaic virus-As (CMV-As) strain was engineered for expression in the plant by using the cauliflower mosaic virus 35S transcript regulatory sequences. The CP gene was cloned into an Agrobacterium-derived binary vector. A chimeric gene was constructed by the cDNA of CMV-As CP and plant expression vector pBI121. The clone, pCMAS66, was first introduced into the phagemid vector pSPORT1 for situating sense orientation for translation and making restriction sites in order to re-introduce plant expression vector, pHI121. The resulting subclone pCASCP02 and plant expression vector pBI121 were treated with BamHI-SacI for excising the target gene and removing GUS gene, respectively. After Agrobacterium transformation by freeze-thaw technique, the clone, pCMASCP121-123 which contains sense orientation of the target gene, was selected and confirmed by restriction endonuclease analysis. The CMV-As CP gene was introduced into A. tumefaciens. The results on tobacco plant transformation with the vector system revealed that the system could be successfully introduced and showed high frequency of selection to putative transformations.