가속도계를 이용한 재료의 영계수 측정방법

손창호(Sohn, Chang-Ho),박진호(Park, Jin-Ho),윤두병(Yoon, Doo-Byung),정의필(Chong, Ui-Pil),최영철(Choi, Young-Chul) 한국소음진동공학회 2006 한국소음진동공학회 논문집 Vol.16 No.11

For the description of the elastic properties of linear objects a convenient parameter is the ratio of the stress to the strain, a parameter called the Young's modulus of the material. Young's modulus can be used to predict the elongation or compression of an object as long as the stress is less than the yield strength of the material. Conventional method for estimating Young's modulus measured the ratio of stress to corresponding strain below the proportional limit of a material using a tensile testing machine. But the method needs precision specimens and expensive equipment. In this paper, we proposed method for estimating Young's modulus using accelerometer. The basic idea comes from that the wave velocity is different as the Young's modulus. To obtain Young's modulus, a group velocity is obtained. It is difficult to measure group velocity. This is because plate medium has a dispersive characteristics which has different wave speed as frequency. In this paper, we used Wigner-Ville distribution to measure group velocity. To verify the proposed method, steel and acryl plate experiments have been performed. Experimental results show that the proposed method is powerful for estimating Young's modulus.

Survey on Insect Fauna and Role of Insect Gardens for Ecotourism

최영철,김종길,최지영,김원태,박해철,황석조,정길상,Choi, Young-Cheol,Kim, Jong-Gill,Choi, Ji-Young,Kim, Won-Tae,Park, Hae-Chul,Hwang, Seok-Jo,Jeong, Gil-Sang Korean Society of Applied Entomology 2009 한국응용곤충학회지 Vol.48 No.4

This study was conducted to investigate insect fauna in the four insect garden sites of Suwon, Yeongyang, Buyeo and Yecheon from 2005 to 2007. Seasonal population size of insects was largest from June to August in all the four sites. In the four sites, Coleopteran insects were dominant followed by Hemiptera and Orthoptera. Unique education/learning programs are successfully run at the insect gardens based on the three geographic types (i.e. urban, mountainous and rural). These activities will help preserve insect biodiversity in the area and visitors better understand life forms such as insects found in the areas. 본 연구는 2005년부터 2007년까지 수원, 영양, 부여와 예천의 곤충 생태원 부지에서 곤충강의 다양성을 조사하였다. 월별 곤충 개체군 크기는 6월부터 8월에 네 조사구역 모두에서 가장 컸다. 전체적으로 딱정벌레목의 곤충이 가장 많이 채집되었으며, 노린재목과 메뚜기목의 곤충이 뒤를 이었다. 각 곤충생태원은 지리적 특색에 맞는 고유한 교육프로그램을 운영하고 있었다. 이러한 연구와 생태원의 활동은 그 지역의 곤충과 같은 생물의 다양성을 보존하고 관람객에게 인식시키는데 중요한 역할을 할 것이다.

Expression of a DNA Sequence Encoding for the Pre-S2 Region of Hepatitis B Virus in E. coli

최영철,김지영,유명희,한문희,Choi, Young-Chul,Kim, Ji-Young,Yu, Myeong-Hee,Han, Moon-H. 생화학분자생물학회 1986 한국생화학회지 Vol.19 No.4

간염 B형 바이러스의 pre-S2 부위를 포함하는 DNA 서열을 pORF1 플라스미드의 ompF와 lacZ 유전자 사이에 끼워 넣어 pHBSC20 재조합 플라스미드를 제조하였다. 플라스미드 pHBSC20를 갖는 E. coli TK1046 균주내에서 OmpF와 $\beta$-galactosidase사이에 pre-S2 부위를 갖는 "tribrid" 단백질이 생성되었다. 이 융합단백질은 SDS-polyacrylamide gel 전기영동에 의해 확인되었고 pre-S2 부위의 항원성은 immunoblot 분석방법에 의해 확인되었다. 융합단백질의 양은 Coomassie blue로 염색한 gel을 densitometer로 측정한 결과 전체 박테리아 단백질중 1-5%를 차지하는 것으로 나타났다. 따라서 pHBSC20 플라스미드를 갖는 박테리아는 pre-S2-$\beta$-galactosidase 융합 단백질을 다량 만들어 낼 수 있으며 이 중에서 pre-S2 부위는 HBV 백신을 생산하는데 유용할 것으로 보인다. A DNA sequence involving pre-S2 region of Hepatitis B virus (HBV) was inserted between ompF and lacZ gene of the plasmid pORF1 to give a recombinant plasmid pHBSC20. In the plasmid pHBSC20 harboring E. coli TK1046 cells, a "tribrid" protein with the translation product of the insert sandwiched between OmpF and $\beta$-galactosidase was produced. The fusion protein was detected by SDS-polyacrylamide gel electrophoresis and the antigenicity of the pre-S2 region was determined by immunoblot analysis. The amount of the fusion protein was estimated as much as 1-5% of the total bacterial protein by densitometric scanning of the Coomassie blue-stained gel. Thus, bacteria transformed with pHBSC20 can provide abundant source of pre-S2-$\beta$-galactosidase fusion protein in which the pre-S2 region may be useful for the production of HBV vaccine.

감염 B 형 바이러스의 pre - S2 부위를 code 하는 DNA 서열의 대장균내 발현

최영철,김지영,유명희,한문희 ( Young Chul Choi,Ji Young Kim,Myeong Hee Yu,Moon H . Han ) 생화학분자생물학회 1986 BMB Reports Vol.19 No.4

A DNA sequence involving pre-S2 region of Hepatitis B virus (HBV) was inserted between ompF and lacZ gene of the plasmid pORF1 to give a recombinant plasmid pHBSC20. In the plasmid pHBSC20 harboring E. coli TK1046 cells, a $quot;tribrid$quot; protein with the translation product of the insert sandwiched between OmpF and β-galactosidase was produced. The fusion protein was detected by SDS-polyacrylamide gel electrophoresis and the antigenicity of the pre-S2 region was determined by immunoblot analysis. The amount of the fusion protein was estimated as much as 1-596 of the total bacterial protein by densitometric scanning of the Coomassie blue-stained gel. Thus, bacteria transformed with pHBSC20 can provide abundant source of pre-S2-β-galactosidase fusion protein in which the pre-S2 region may be useful for the production of HBV vaccine.

대장균에서 융합단백질의 대량생산을 위한 베타갈락토시다제 폴리펩티드 길이의 최적화

최영철,이상철,한문희,유명희 ( Young Chul Choi,Sang Chul Lee,Moon H . Han,Myeong Hee Y ) 생화학분자생물학회 1988 BMB Reports Vol.21 No.1

Plasmid vectors for cloning and directing the synthesis of large amounts of fusion proteins in E. coli were constructed. These plasmids carried tac promoter, the coding sequence of amino terminal portion of β-galactosidase, and the polylinker region at the 3`-end of truncated lacZ. When E. coli MC1061 cells were transformed with these plasmids, 25-60% of the total cellular proteins were represented by the lacZ polypeptides. The overproduced proteins formed inclusion bodies inside the cells. When the amounts of recombinant proteins produced by these plasmids were examined, the higher yield was observed with those of shorter lacZ polypeptides. The length of recombinant polypeptide with the maximum yield (60%) was about 280 amino acids long. However, when the length of β-galactosidase decreased to 200 residues as in pCT30 vector, the yield of recombinant proteins decreased dramatically. When the length of polypeptide increased again to 260 residues by fusing pre-S2 sequence of hepatitis B virus to lacZ sequence in pCT30, the yield of fusion polypeptides increased to over 50% of total cellular proteins.

Optimization of the ${\beta}$-galactosidase Polypeptide Length for the Overproduction of Fusion Proteins in E. coli.

최영철,이상철,한문희,유명희,Choi, Young-Chul,Lee, Sang-Chul,Han, Moon-H.,Yu, Myeong-Hee 생화학분자생물학회 1988 한국생화학회지 Vol.21 No.1

대장균 내에서 융합단백질을 다량 생산하기 위한 발현벡터들이 개발되었다. 이들 플라스미드 벡터들은 tac 전사활성화 서열, 베타갈락토시다제의 아미노 말단을 코우드하는 뉴클레오티드 서열 그리고 그의 3'말단에 클로닝 부위로서 폴리링커를 지니고 있다. 대장균 MC1061 균주를 이들 플라스마드로 형질전환 시키고 재조합 단백질의 생산을 유도하였을 때 절단된 베타갈락토시다제 폴리펩티드의 양은 전체 세포단백질의 25-60% 정도가 되었다. 이렇게 생산된 재조합 단백질들은 세포내에서 함유체 (inclusion body) 상태로 축적되었다. 이들 플라스미드에 의해 생산되는 폴리펩티드의 수율을 조사하였을 때 길이가 짧을수록 수율이 올라감을 알 수 있었는데, 길이가 280개 아미노산 정도일 때 최대의 수율(60%)을 나타냈다. 하지만 pCT30 플라스미드에서와 같이 길이가 200개 아미노산 정도로 너무 짧아지면, 수율이 현저하게 감소하였다. 이 pCT30 플라스미드의 베타갈락토시다제 서열의 3'말단에 간염 바이러스의 pre-S2 서열을 연결시켜, 생산되는 융합 폴리펩티드 길이를 260개 아미노산으로 늘어나게 하였을 때 융합 단백질의 수율은 다시 총 세포 단백질의 50% 이상으로 증가하였다. Plasmid vectors for cloning and directing the synthesis of large amounts of fusion proteins in E. coli were constructed. These plasmids carried tac promoter, the coding sequence of amino terminal portion of ${\beta}$-galactosidase, and the polylinker region at the 3'-end of truncated lacZ. When E. coli MC1061 cells were transformed with these plasmids, 25-60% of the total cellular proteins were represented by the lacZ polypeptides. The overproduced proteins formed inclusion bodies inside the cells. When the amounts of recombinant proteins produced by these plasmids were examined, the higher yield was observed with those of shorter lacZ polypeptides. The length of recombinant polypeptide with the maximum yield (60%) was about 280 amino acids long. However, when the length of ${\beta}$-galactosidase decreased to 200 residues as in pCT30 vector, the yield of recombinant proteins decreased dramatically. When the length of polypeptide increased again to 260 residues by fusing pre-S2 sequence of hepatitis B virus to lacZ sequence in pCT30, the yield of fusion polypeptides increased to over 50% of total cellular proteins.

Synthesis and Characterization of Fully Aromatic Polyazomethines with Cyano Functional Group

최영철,이상훈,김민수,류경문,이상철,정영규,Choi, Young Chul,Lee, Sang Hoon,Kim, Min Su,Ryu, Kyoung Moon,Lee, Sang Cheol,Jeong, Young Gyu The Korean Fiber Society 2018 한국섬유공학회지 Vol.55 No.2

We herein report the preparation and characterization of a new type of fully aromatic polyazomethines (PAMs) with the cyano functional group. For synthesizing this compound, two homopolymers, poly(nitrilo-2-cyano-1,4-phenylenenitrilomethine-1,3-phenylenemethine) (mPAM) and poly(nitrilo-2-cyano-1,4-phenylenenitrilomethine-1,4-phenylenemethine) (pPAM) and their copolymers, poly[(nitrilo-2-cyano-1,4-phenylenenitrilomethine-1,4-phenylenemethine)-co-(nitrilo-2-cyano-1,4-phenylenenitrilomethine-1,3-phenylenemethine)]s (coPAMs), were synthesized via the polycondensation of terephthalaldehyde (TPA), isophthalaldehyde (IPA), and 2-cyano-1,4-phenylenediamine (cyPPD) monomers in an $NMP/CaCl_2$ solvent system. The $^1H-NMR$ and FT-IR spectra confirmed that all the aromatic PAMs were successfully synthesized and that the output compositions of coPAMs were almost identical to the relative input composition of TPA and IPA to cyPPD. mPAM, with a nonlinear meta-phenylene moiety, exhibited good solubility in organic solvents such as NMP, DMSO, and DMAc, while pPAM and coPAMs were partially soluble in those solvents owing to the rigid para-phenylene moiety in the main chains. Accordingly, unlike mPAM, pPAM and coPAMs were semicrystalline, as revealed by their X-ray diffraction patterns. Interestingly, the peak decomposition temperatures ($667-769^{\circ}C$) in air were higher than those ($452-594^{\circ}C$) in nitrogen, although the residues (74-81%) at $800^{\circ}C$ in nitrogen were far higher than those (16-47%) in air.

고성능 하이볼륨 슬래그 시멘트 페이스트의 고로슬래그 미분말 분말도에 따른 수화 및 강도 특성

최영철,신동철,황철성,Choi, Young Cheol,Shin, Dongcheol,Hwang, Chul-Sung 한국구조물진단유지관리공학회 2017 한국구조물진단유지관리공학회 논문집 Vol.21 No.5

최근 온실가스 감축을 위해 시멘트 클링커를 대체하여 고로슬래그 미분말을 다량 치환한 하이볼륨 슬래그 시멘트에 대한 연구 활발히 진행되고 있다. 하지만, 수화열 및 내구성 등 다양한 장점에도 불구하고 초기 재령에서의 낮은 강도 발현 등의 문제점으로 인해 실제 현장의 적용에 한계점을 가지고 있다. 본 연구는 이러한 점을 극복하고자 GGBFS 혼입률에 따른 페이스트의 압축강도, 수화열 등의 특성을 분석하였다. GGBS 분말도에 따른 4종류와 치환율 35%, 50%, 65%, 80% 4수준으로 하여 총 16개의 배합에 대해 실험을 수행하였다. 실험결과 낮은 물-바인더 비에 의한 고성능 하이볼륨 슬래그 시멘트 페이스트 배합은 초기 재령에서의 낮은 압축강도의 한계점을 극복할 수 있을 것으로 판단된다. 또한 GGBS의 분말도는 고성능 하이볼륨 슬래그 시멘트 페이스트의 초기 재령에서의 압축강도 증진에는 효과가 있지만, 28일 이후의 장기 강도에는 큰 영향이 없는 것으로 나타났다. Recently, lots of researches on concrete with high volume mineral admixtures such as ground granulated blast-furnace slag(GGBS) have been carried out to reduce greenhouse gas. The high volume GGBS concrete has advantages such as low heat, high durability, but it has a limitation in practical field application, especially low strength development in early ages. This study investigated the compressive strength and hydration characteristics of high performanc and volume GGBS cement pastes with low water to binder ratio. The effects of fineness($4,330cm^2/g$, $5,320cm^2/g$, $6,450cm^2/g$, $7650cm^2/g$) and replacement(35%, 50%, 65%, 80%) of GGBS on the compressive strength, setting and heat of hydration were analyzed. Experimental results show that the combination of high volume slag cement paste with low water to binder ratio and high fineness GGBS powder can improve the compressive strength at early ages.

STS 학습 프로그램 적용이 실업계 고등학생들의 과학 성취도 및 태도에 미치는 효과

최영철,윤일희,Choi, Young-Chul,Yoon, Ill-Hee 한국지구과학회 2001 한국지구과학회지 Vol.22 No.4

이 연구의 목적은 STS 학습 프로그램의 적용이 실업계 고등학생의 과학과 관련된 태도에 미치는 효과를 찾는 것이다. 이를 위하여 고등학교 ‘공통 과학’ 중 지구과학 영역을 선택하였고, STS 학습 프로그램을 1년 간 경북 구미시의 실업고등학교 2학년 여학생 6개반(318명)을 대상으로 하여 교수-학습에 적용하였다. 이런 과정에서 STS 학습 프로그램에 필요한 학습 보조 자료들도 개발하여 활용하였다. 그 결과 STS 학습 프로그램의 적용 후가 적용 전보다는 학생들의 과학 성취도 및 태도에 긍정적인 효과를 나타낸 것으로 나타났다. The purpose of this study is to investigate the effects of the STS program on vocational high school students' science-related attitudes. In order to examine, we selected the content of instructions at the Earth Science content in the "Common Science" and applied the STS program for one year to the second grade students of six classes (N = 318) in a girls high school located in Kumi City, Kyungpook, Korea. For this study, we developed the instructional methods and then applied to the STS program. The result of this study revealed that the STS program on students' science achievement and attitudes were effective.

간염 B 형 바이러스 표면항원 대장균 내 발현

최영철,김지영,유명희,한문희 ( Young Chul Choi,Ji Young Kim,Myeong Hee Yu,Moon H . Han ) 생화학분자생물학회 1986 BMB Reports Vol.19 No.4

Three different HBsAg sequences encoding for S region, pre-S2 plus S region, and pre-S2 fused with a portion of β-galactosidase have been expressed in E. coli under the control of lac promoter. When the S region containing HBsAg genes were expressed constitutively in E. coli HB101, the growth inhibition of recombinant cells was observed. However, the constitutive expression of pre-S2 fused with apeptide (N-terminal portion of β-galactosidase) was not detrimental to the E. coli HB101 cells. The antigenicity of the hybrid pre-S2 protein seems to be conformation-independent: treatment of 2-mercaptoethanol or 2-mercaptoethanol/SDS did not abolish the antigenicity.