콘크리트 구조물용 GFRP리바의 기계적 특성에 관한 연구

한길영,이동기,김성용,전상기,최종대,박준식 조선대학교 에너지.자원신기술연구소 2000 에너지·자원신기술연구소 논문지 Vol.22 No.2

In this paper was studied on the mechanical characteristics of Glass Fiber Reinforced Plastics(GFRP) of the steel bar it is to replace The advantage of FRP such as high strength low weight and chemical inertness or noncorrosiveness can be fully exploited. GFRP bar were successfully fabricated at 10mm nominal diameters and hollow types using a pultrusion method Tensile and bending specimens from this bar were tested and compared with behavior of GFRP rebar and steel bar.

고등학생 및 대학생의 AIDS에 관한 지식 및 태도 비교조사

최길명,선우섭,이혁,조진우,이한 경희대학교 사회체육연구소 1996 體育科學論叢 Vol.- No.9

The present research is to provide basic data for establishing an effective educational program for preventing AIDS. The following are the results of data collected from 2,123 high-school third grade students (1,051 male and 1,072 female) and 2,109 college freshman students (1,483 male and 626 female) and analyzed in terms of their status, sex, and region: 1. As for the corrects answers to the questions concerning knowledge of AIDS, high-school and college male students tend to show higher grades, especially in theepidemic and non-epidemic aspects of AIDS. 2. As for the correct answers to the questions concerning attitudes to AIDS, high-school female students tend to show higher grades. 3. As for the corrects answers to the questions on knowledge of AIDS, college students received higher grades (p<.001), especially in the epidemic and non-epidemic aspects (16 questions) of AIDS. 4. As for the correct answers to the questions concerning attitudes to AIDS, college students received higher points (p<.05), especially in preventive attitudes (10 questions). 5. The regional order of correct answers to the questions concerning knowledge of AIDS in high-school students is Kyungsang, Choongchung, Kangwon, Chunla, Cheju, Seoul, and Kyunggee. But, the order of correct answers in college students is Chunla, Seoul, Kyungsang, Kangwon, Choongchung, Kyunggee, and Cheju. 6. The regional order of correct answers to the questions concerning attitudes to AIDS in high-school students is Choongchung, Cheju, Kyungsang, Seoul, Kangwon, Chunla, and Kyunggee. However, the order of correct answers in college students is Kangwon, Kyungsang, Choongchung, Chunla, Seoul, Kyunggee, and Cheju. The research result shows that the educational program for preventing AIDS must take into consideration knowledge on epidemic and non-epidemic aspects of AIDs and preventive attitudes toward AIDS. And, it also proves that it is necessary to devise an AIDS educational program for high-school and college students.

해수 환경에서의 철근과 GFRP리바의 굽힘강도 특성에 관한 연구

한길영,최명선,곽상묵 朝鮮大學校 機械技術硏究所 2003 機械技術硏究 Vol.6 No.1

Fiber reinforced plastics(FRP) attracted muGh attention as a form of concrete reinforcement in the past decade. Compared with existing construction matrials, FRP possesses many advantages such as light-weight. high-strength, corrosion resistant properties, etc. Among other fabrication process of GFRP, pultrusion is one of the promising ones for civil infrastructure application. This paper describes the need for a ductile Fiber Reinforced Plastics (FRP) reinforcement for concrete structures. To promte the degradation of the adhesive condition a t the fiber-matrix micro interface without matrix dissolution loss were carried out in salt water surrounding. The absorption properties and the bending strength were compared about GFRP rebar and steel bar. Due to the fiber permeability absorption of moisture take place through both the fiber and the matrix. The diffusivities obtained for Glass-Polyester are found to be in good agreement with those available in the existing literature.

니트섬유강화 복합재료의 기계적 성질에 관한 연구

한길영,이동기,최병기,오환교,신용욱,전수영 조선대학교 에너지.자원신기술연구소 1999 에너지·자원신기술연구소 논문지 Vol.21 No.2

Using conventional textile techniques such as weaving, braiding, knitting and stitching it is possible to produce a wide range two and three dimensional fiber preforms. However, so far only a limited attention has been given to knitted fabrics in composite industry. This is mainly due to the opinion that knitted fabric reinforced composites posses low mechanical properties owing to their looped fiber architecture. But it is possible to obtain desired mechanical properties by selecting proper knitted fabric structure. In this paper, tensile failure load and displacement of one yarn, four yarns and knitted fabrics of ten yarns of kevlar fiber were determined experimentally in the unidirection. Mechanical properties of plain weft knitted fabrics reinforced composite intrusion beam for car side door application were investigated experimentally, which compared with desire value of American Fedral Motor vehicles Safety Standard (FMVSS) and presented the results.

저분자량 폴리에틸렌이민을 이용한 유전자 송달 및 발현 유효성 연구

정길재,박귀례,신지영,최한곤,오유경 한국약제학회 2004 Journal of Pharmaceutical Investigation Vol.34 No.4

Branched and linear polyethylenimines (PEIs) have been studied as efficient and versatile agents for gene delivery in vitro and in vivo. PEIs exist in a linear or branched topology and are available in a wide range of molecular weight (Mw). Most studies have been done using PEIs with Mw higher than 10Kd. This study was aimed to test the transfection efficiency and the cell viability following gene delivery using PEI of Mw 2Kd, a relatively lower Mw cationic polymer. We used murine interleukin-2(mIL-2) plasmid DNA complexed with branched PEI 2Kd or 25Kd, and transfected them into a myoblast muscle cell line, C2C12. The cellular uptake of mIL-2 plasmid DNA was determined using quantitative polymerase chain reaction. RNA transcript levels were studied in the myoblast cells. Our results show that PEI 2Kd was as effective as PEI 25Kd in celluar gene delivery and transfection efficiency in C2C12 cells. Moreover, MTT assay indicated that PEI 2Kd/DNA complexes did not significantly reduce the cell viability regardless of N/P ratios. These results suggest that PEI of Mw 2Kd might play a role as effective and low toxic nonviral vector systems for muscular cell lines.

월쉬 함수를 이용한 비선형계의 2계층 최적제어

김세찬,최영길,이한석 부천대학 2000 論文集 Vol.21 No.-

This paper presents a new algorithm for two level optimal control to non-linear systems. The proposed method is simple because the solutions are obtained by only exchaging informations of coefficient vector based on interaction prediction principle and Walsh Transformation in upper and lower level. Since we solve two point boundary problem with backward integral operational matrix of Walsh Function to obtain the optimal vector of each independent subsystem, we can reduce more operational burden than conventional numerical method. In simulation, the proposed algorithm's usefulness is proved by comparison with global optimal control methods.

螢光像 測定法으로 分析한 HUMACTBP2 遺傳座位에 대한 韓國人의 遺傳的 多樣性과 法醫學的 有用性

황적준,남용석,최하주,이혜린,한길로 大韓法醫學會 1997 대한법의학회지 Vol.21 No.1

The HUMACTBP2 locus was investigated to collect population genetic data in the Korean population and to evaluate the applicability for the forensic field. An Automatic fluorescent-based sequencer (377 automatic DNA sequencer, ABI) was used to detect amplified fragments of the HUMACTBP2 locus electrophoresed on 4% denaturing polyacrylamide sequencing gels. ACTBP2 allelic ladder consisting of different sizes of 18 alleles was constructed and employed as an internal size standard in combination with a GS-350 size standard for precision of allele-band sizing. By utilizing different fluorescent dyes, both the allelic ladders and samples were able to be analyzed in the same lane by 99% precision of allele-band sizing. Among the Korean population (n=224), 26 alleles in the range of 239-313 bp are determined. Allele No. 6 is found 45 times (0.100) which is mostly frequent, and the rest of allele is distributed with their relative frequency of 0.112-0.100. The comparison between observed and expected numbers of homozygous and heterozygous individuals confirms that ACTBP2 locus is in the state of Hardy-Weinberg equilibrium among the Korean population. The heterozygosity is 0.9389±0.0034(93.89%), and the power of discrimination)PD) and power of exclusion(PEX) are calculated to be 0.991(99.1%) and 0.890(89.0%), respectively, showing the high informativeness for individual identification. Thus, these results mean that the HUMACTBP2 locus can effectively be used for the forensic application.

비강비호즈킨 림프종의 전산화단층촬영 소견 : CT Features

노태연,백호길,원종부,박성호,박오봉,백승국,신미정,김봉기,최한용 침례병원 1998 浸禮病院學術誌 Vol.14 No.-

정신분열병과 N-Methyl-D-Aspartate 수용체 유전자와 연관된 VNTR 표지자인 D9S158 다형성의 연합

김종원,채영규,정은기,김길숙,박강규,이영호,최인근,양병환,한진희 大韓神經精神醫學會 1998 신경정신의학 Vol.37 No.5

정신분열병과 NMDA 수용체와 연관된 D9S158 유전적 표지자와의 연관성을 알아보기 위해 75명의 정신분열병 환자군과 87명의 정상대조군을 대상으로 중합효소연쇄반응을 이용하여 연합연구를 시행하여 다음과 같은 결론을 얻었다. D9S158 유전좌위에는 모두 8개의 대립유전자가 있었고, 각 대립유전자는 cytosine-adenine염기가 반복되는 217염기쌍에서 233염기쌍의 형태였다. 먼저 정신분열병 환자와 정상대조군의 대립유전자의 빈도를 비교해 본 결과 통계적으로 유의한 차이를 보이지 않았다(p〉.05). 환자군을 좀 더 동질적으로 만들기 위해 정신분열병의 가족력 유무, 음성 및 양성증상, 연성신경학적 징후, DSM-IV 임상아형에 따라 환자군을 나누어 대립유전자의 빈도를 비교해 본 결과, 특정 임상양상과 관련이 있는 대립유전자를 발견하지 못하였다. 결론적으로 본 연구에서는 D9S158 유전좌위와 정신분열병의 연관성을 입증하지 못하였으나 NMDA 수용체 유전자주위의 다른 표지자나 좀 더 유전적으로 동질한 환자군을 대상으로 한 추후연구가 필요할 것으로 생각된다. An association study with Korean schizophrenic patients(N=75) and normal controls(N=87) was performed to find the relationship between D9S158 polymorphism and schizophrenia using polymerase chain reaction. Eight different alleles of a dinucleotide polymorphism on D9S158 locus were observed in both group. When we compared the frequencies of alleles between schizophrenics and normal controls, there was no significant difference between two groups. To increase homogeneity of schizophrenic group, we divided schizophrenic group by clinical phenotypes such as family history, negative and positive symptoms(PANSS), soft neurologic signs(NES-K) and DSM-IV diagnostic subtypes. Then we compared the frequencies of alleles among subgroups of clinical phenotypes, and there were no significant differences between subgroups(p〉.05). Although our findings fail to provide an evidence of association between schizophrenia and D9S158 locus, further investigation of other loci that are linked to NMDA receptor gene may be needed in genetically homogeneous subgroups of schizophrenia.

결핵의 진단법으로서 중합효소 연쇄반응 검사의 가치

서상철,은상진,김한길,송경은,서장수,최성만,이원길,김재식,김중명 慶北大學校 醫科大學 1994 慶北醫大誌 Vol.35 No.1

목적 : 결핵균 동정을 위한 중합효소 연쇄반응을 임상병리검사로서 적용하기 위한 기초 실험으로 분석학적 예민도와 특이도를 알아보고 검토된 조건에 의한 중합효소 연쇄반응을 실제 임상 가검물에 적용하기 위함이다. 재료 및 방법 : Ziehl-Neelsen염색 양성인 객담, 뢰벤스타인-젠센(Loewenstein-Jensen) 배지에서 분리된 결핵균 및 M. tuberculosis H37Rv를 비롯한 항산균 표준균주 11주와 비항산균 10주를 사용하여 2가지 DNA의 분리법, 3set 프라이머, 3종류 중합효소, 2가지 미량 원심시험관 및 Easy-Cycler^R(Ericomp사, 미국)와 수조형으로 검사를 시행하여 DNA 증폭 산물을 비교하였다. 또한 이미 지일-닐슨 염색법에 의한 선별검사에서 음성을 나타낸 객담 53예, 소변 101예, 삼출액 128예, 뇌척수액 54예 등 총 370예의 임상가검물을 대상으로 하여 위에서 검토된 중합효소 연쇄반응 조건으로 검사한 성적과 지일-닐슨 염색법, 배양법 성적과 비교하였다. 결과 : DNA분리방법 2가지와 3가지 중합효소는 분석학적 예민도와 5fg로 나타나 차이를 발견할 수 없었으며, 프라이머 P1, P2쌍은 예민도가 5fg, 프라이머 INS1, INS2쌍과 프라이머 Pt3, Pt6쌍의 예민도는 0.5fg이었다. Easy-Cycler^R가 수조형에 비해 높고, 미량 원심시험관은 Robbins사 제품이 Sarstedt사 제품에 비해 높은 분석학적 예민도를 나타냈다. 프라이머 P1, P2쌍과 프라이머 INS1, INS2와 Pt3, Pt6 2쌍의 프라이머의 특이도에 있어서는 항산균 표준균주 중 M. tuberculosis H37Rv, M. tuberculosis ATCC 27294, M. bovis ATCC 29312의 3주에서 특이 증폭 띠를 관찰할 수 있었다. 그러나 비결핵성 항산균 8주에는 특이 증폭 띠를 나타내지 않았다. 또 비항산균 10주에도 특이 증폭 띠가 관찰되지 않았다. 따라서 Robbins사의 미량 원심시험관과 proteinase-K법에 의한 DNA분리방법에 Easy-Cycler^R를 사용하여 프라이머 INS1, INS2쌍으로 일차 중합효소 연쇄반응을 시행한 후 프라이머 Pt3, Pt6쌍으로 이차중합효소 연쇄반응을 시행하는 방법을 370예의 임상가검물에 시행하였고 지일-닐슨 염색법과 결핵균배양검사도 동시에 시행한 결과 중합효소 연쇄반응 양성은 106예(28.6%), 배양 양성은 27예(7.3%) 및 염색 양성은 18예(4.9%)였으며, 결핵환자는 141명(38.1%)였다. 370예의 임상 가검물로 시행한 중합효소 연쇄반응의 진단학적 예민도와 특이도, 양성결과 예측치 및 음성결과 예측치는 68.8%, 96.1%, 91.5% 및 83.3%로 각각 나타났다. 결론 : 결핵균 동정을 위한 중합효소 연쇄반응은 배양검사에 비해 신속하며, 분석학적인 예민도와 특이도가 뛰어나므로 결핵 진단을 위한 임상병리검사로서 유용하다고 사료됨. In this study, We investigated the optimal conditions of polymerase chain reaction(PCR) assay for the rapid identification of Mycobacterium tuberculosis in clinical specimens as routine laboratory test. So we have compared two DNA isolation methods, 3 polymerases, 2 set of primer, 2 kinds of thermocycler and 2 microtubes. We evaluated two DNA isolation methods, bead-beating method and proteinase-K method, the latter was more sensitive than the former. In comparision of two sets of primers, P1 and P2 primers detecting 123-base pair fragment of IS6110 made from Biosnthesis(U. S. A.) and INS1 and INS2 primers detecting 245-base pair fragment of IS986 showed equally sensitive results ie. 5fg. Specificity of primers were tested and INS1 and INS2 primers gave 245-base pair product from M. tuberculosis H37Rv, M. tuberculosis ATCC 27294 and Mycobacterium bovis ATCC 29312 but not from 8 nontuberculous mycobacterial strains such as M. kansasii ATCC 12478, M. terrae ATCC 15755, M. intracellurae ATCC 13950, M. avium ATCC 25281, M. gordonae ATCC 14470, M. fortuitum ATCC 6841, M. smegmatis ATCC 19420, M. scrofulaceum ATCC 19981. Coagulase-positive staphylococcus, coagulase-negative staphylococcus, streptococcus, Esccherichia coli, Serra-tia marcescens, Klebsiella pneumoniae, Enlerobacter aerogenes, Enterobacter cloacae, Acinetobacter calcoaceticus, Pseudomonas aerugonosa showed no 245-base pair amplification product. PCR by the P1 and P2 primers showed 123-base pair amplification product from M. tuberculosis H37Rv, M. tuberculosis ATCC 27294 and Mycobacterium bovis ATCC 29312 but not from 8 nontuberculous mycobacterial strains such as M. kansasii ATCC 12478, M. terrae ATCC 15755, M. intracellularae ATCC 13950, M. avium ATCC 25281, M. gordonae ATCC 14470, M. fortuitum ATCC 6841, M. smegmatis ATCC 19420, M. scrofulaceum ATCC 19981. Coagulase-postive staphylococcus, coagulase-negative staphylococcus, streptococcus, Escherichia coli, Serratia marcescens, Klebsiella pneumoniae, Enlerobacter aerogenes, Enterobacter cloacae, Acinelobacler calcoaceticus, Pseudomonas aeruginosa showed no 123-base pair amplification product. In comparision of polymerase, Taq DNA polymerase^R(Promega Co., U. S. A.) was more cost effective than Ampli Tag^R(Perkin-Elmer Cetus, U. S. A.), but these two were equally sensitive and specific in the detection of M. tuberculosis-specific DNA. Tac polymerase (Korea'Biotech, Korea) showed many nonspecific bands. In comparision of thermocycler, Easy-Cycler^R(Ericomp, U. S. A.) was more sensitive than water-bath type and in that of microtubes Robbin's were more sensitive than Sarstedt's PCR results were compared with results of culture for M. tuberculosis and Ziehl-Neelsen stain in 370 clinical specimens that were negative by initial Ziehl-Neelsen stain. There were 27 specimens(7.3%) that were positive for M. tuberculosis by culture, 18(4.9%) specimens that were positive by Ziehl-Neelsen stain, and 106 specimens(28.6%) that were positive for PCR and 141 cases that were positive for tuberculosis. Overall sensitivity, specificity, positive predictive value and negative predictive value were 68.8, 96.1, 91.5 and 83.3% respectively, for PCR; 19.1, 100, 100, and 66.8%, respectively for culture; and 12.8, 100, 100, and 59.0% respectively for Ziehl-Neelsen stain.