전도성 고분자 센서 어레이를 이용한 휘발성 유기 화합물 가스 인식

이경문,주병수,유준부,황하룡,이병수,이덕동,변형기,허증수 한국센서학회 2002 센서학회지 Vol.11 No.5

휘발성 유기 화합물 가스(Volatile Organic Compounds)를 인식하고 분석하기 위하여 전도성 고분자 센서어레이를 이용한 시스템을 제작하였다. Polypyrrole와 Polyaniline을 화학중합법으로 센서에 전도성고분자막을 형성하였고 이를 통해 VOC 검지용 센서 어레이를 제작하였다. 센서어레이로부터 측정되는 다차원 데이터는 주성분분석법(PCA)과 RBF(Radial Basis Function Network)을 이용하였다. 제안된 시스템으로 VOCs 가스를 인식하는데 있어서 RBF Network이 PCA방식보다 더욱 효율적인 것으로 판단되었다. We fabricated gas recognition system using conducting polymer sensor array for recognizing and analyzing VOCs(Volatile Organic Compounds) gases. The polypyrrole and polyaniline thin film sensors which were made by chemical polymerization were employed to detect VOCs. The multi-dimensional sensor signals obtained from the sensor array were analyzed using PCA(principal component analysis) technique and RBF(radial basis function) Network. Throughout the experimental trails, we confirmed that RBF Network is effective than PCA technique in identifying VOCs.

Impedance를 이용한 전도성고분자 센서의 가스감응특성

이경문,유준부,이병수,전희권,이상태,이덕동,허증수 경북대학교 센서기술연구소 2002 센서技術學術大會論文集 Vol.13 No.1

단일전극을 가진 마이크로 가스센서의 제작 및 특성

송갑득,박영일,이상문,이윤수,최낙진,주병수,서무교,허증수,이덕동 한국센서학회 2002 센서학회지 Vol.11 No.6

센서의 안정도와 감도를 개선시킬 수 있는 단일전극을 가진 열선형 마이크로 가스센서를 제작하였다. 일반적으로, 금속산화물 반도체를 이용한 가스센서는 히터전극과 감지전극의 두 개의 전극을 가지고 있다. 제작된 센서는 히터전극위에 감지물질을 형성하여 단일 전극을 가지는 구조를 가지고 있다. 히터와 감지전극으로 사용되는 Pt는 glass 기판위에 스퍼터링법으로 형성하였으며, SnO_2 감지물질은 제작된 Pt 전극위에 열증착시켜 형성하였다. SnO_2막은 lift-off 공정을 이용해서 패턴을 형성하고 1시간 동안 산소분위기에서 열산화하였다. 제작된 소자의 크기는 1.92x.1 mm^2 이다. CO 가스에 대한 감지특성을 조사한 결과 1,000 ppm에 대해 100 mV의 출력변화를 나타내었으며, 넓은 농도범위(0 ~ 10,000 ppm에서 선형적인 전압출력을 나타내었다. 또한 가스 반응 전과 반응 후의 전압출력을 비교해 볼 때, 1 % 이내의 편차를 나타내는 우수한 회복성을 나타내었다. Micro gas sensor with single electrode was proposed for improving stability and sensitivity, Generally, metal oxide gas sensors have two electrodes for heating and sensing. This fabricated new type sensor have only a single electrode by forming a sensing material onto heating electrode. Pt as a heating and sensing electrode was sputtered on glass and a SnO_2 sensing material was thermally evaporated on Pt electrode. SnO_2 was patterned by lift-off process and then thermally oxidized in O_2 condition for 1 hr., 600 ℃. The size fabricated sensor was 1.9 x 2.1 mm^2. As a result of CO gas sensing characteristics, this sensor showed 100 mV change for 1,000 ppm and linearlity for wide range(0 ~ 10,000 ppm) of gas concentrations. And the sensor shows a good recovery characteristics of 1 % deviation compared to initial resistance.

FET형 포도당 센서를 위한 PVP/DAST/GOD 고정화막 형성기술

조병욱,이수근,박이순,이종덕,손병기 경북대학교 센서기술연구소 1992 센서技術學術大會論文集 Vol.3 No.1

광중합형 구치부 수복재료의 중합수축량과 중합수축력

박성호,이순영,조용식,김수선,이창재,김영주,이봉희,이광성,노병덕 大韓齒科保存學會 2003 Restorative Dentistry & Endodontics Vol.28 No.4

The purpose of present study was to evaluate the polymerization shrinkage stress and amount of linear shrinkage of composites and compomers for posterior restoration. For this purpose, linear polymerization shrinkage and polymerization stress were measured. For linear polymerization shrinkage and polymerization stress measurement, custom made Linometer (R&B, Daejon, Korea) and Stress measuring machine was used (R&B, Daejon, Korea). Compositers and compomers were evaluated; Dyract AP (Dentsply Detrey, Gumbh, German) Z100 (3M Dental Products, St. Paul, USA) Pyramid (Bisco, Schaumburg, USA) Synergy Compact (Coltene, Altstatten, Switzerland), Heliomolar (Vivadent/Ivoclar, Liechtenstein), and Compoglass (Vivadent Ivoclar/Liechtenstein) were used. 15 measurements were made for each material. Linear polymerization shrinkage or polymerization stress for each material was compared with one way ANOVA with Tukey at 95% levels of confidence. For linear shrinkage ; Heliomolar, Surefil<Synergy Compact, Z100<Dyract AP<Pyramid, Compoglass F (p<0.05) For Shrinkage stress ; Heliomolar < Z100, Pyramid<Synergy Compact, Compoglass F<Dyract AP<Heliomolar HB, Surefil (p<0.05)

열적 변화를 이용한 실내환경 가스의 분류

최낙진,심창현,송갑득,주병수,이윤수,이상문,이덕동,허증수 한국센서학회 2002 센서학회지 Vol.11 No.5

단일 기판위에 온도측정용 Pt 박막과 Pt 히터 그리고 가스 감지를 위하여 순수한 SnO_2 박막과 Pt가 첨가된 SnO_2박막을 설계하고 제작하였다. 제작된 소자는 실내환경가스인 이산화탄소, 프로판 그리고 부탄의 분류에 응용되었다. 동작 온도를 가변하기 위하여 히터의 입력 전압을 사다리꼴로 인가하면서 SnO_2 감지막의 반응특성과 실내환경가스들에 대한 분류여부를 조사하였다. 감지막 반응특성곡선에서 여러 변수들을 추출한 후 주성분분석(principal component analysis : PCA)을 통하여 가스 분류 특성을 검증하였다. Two SnO_2 based sensing films(pure SnO_2 and SnO_2/Pt) and a Pt thin film for temperature sensor on an alumina substrate were designed and fabricated for classifying the indoor environmental gases. By controlling the heating power in the shape of trapezoid, unique four sensing response curves created from both SnO_2 film and SnO_2/Pt film. Then, various parameters were extracted from sensing response curves and carried out principal component analysis(PCA). The results confirm that a sensor array with the proposed operating mode was extremely effective in classifying indoor environmental gases such as CO_2, C_3H_8, C_4H_10.

G292 세포에서 세포막 신장으로 활성화되는 K^+통로의 특성

이상국,정동근,서덕준,박수병 대한치과교정학회 2000 대한치과교정학회지 Vol.30 No.2

본 연구에서는 인체 골종양에서 유래한 G292세포를 이용하여 압력으로 세포막을 신장(stretch)시켰을 때 K+ 통로의 전기적 활성 변화를 연구하였다. 배양된 세포에서 유리전극을 이용하여 세포막 내측이 유리전극의 외부로 향하도록 inside-out patch를 얻어 단일이온통로전류를 막전압고정법 (patch clamp recording)으로 기록하였다. G292세포의 세포막 내외에 140 mM KCl용액이 있는 상태에서 유리전극내 전압을 -80 mV로 고정했을 때 전도성이 270±27 pS, 113±12 pS, 48±8 pS인 3가지 종류의 K+통로를 관찰하였다. 전도성이 낮은 48 pS의 K+ 통로는 모든 세포막에서 관찰하였으며 270 pS 및 113 pS의 K+ 통로는 일부 세포에서만 관찰하였다. 48 pS의 K+ 통로는 세포막 외측에 음의 전압을 가하면 활성화되고 양의 전압을 가하면 활성화되지 않는 외향성 정류특성을 보였다. 세포막 외측에 음압을 가하면 48pS의 K+통로는 활성화되었으며 이온 통로가 열리는 확률(Popen)이 가하는 압력에 비례하여 증가하였다. 이러한 결과는 G292세포주에 3가지 종류의 K+통로가 존재하며 전도성이 낮은 48pS의 K+통로만이 세포막 신장에 의하여 직접적으로 활성화되는 특성을 보였다. 이러한 K+ 통로의 활성화는 세포가 기계적 자극을 받아 세포막이 신장되면 세포막전압을 과분극시키며 조골세포에서 기계적 강수기로서의 기능을 수행하여 조골세포의 골개조에 관여할 것으로 추측된다. K+-selective ion channels were studied in excised inside-out membrane patches from human osteoblast-like cells (G292). Three classes of K- channels were present and could be distinguished on the basis of conductance. Conductances were 270±27 pS, 113± 12 pS, 48±8 pS according to their approximate conductances in symmetrical 140 mM KCI saline at holding potential of -80 mV. It was found that the small conductance (48 pS) K+ channel activation was dependent on membrane voltage. In current-voltage relationship, small conductance K+ channel showed outward rectification, and it was activated by the positive potential inside the membrane. In recordings, single channel currents were activayed by a negative pressure outside the membrane. The membrane pressure increased Popen of the K+ channel in a pressure-dependent manner. In the excised-patch clamp recordings, G292 osteoblast-like cells have been shown to contain three types of K+ channels. Only the small conductance (48 pS) K+ channel is sensitive to the membrane stretch. These findings suggest that a hyperpolarizing current, mediated in part by this channel, may be associated with early events during the mechanical loading of the osteoblast. In G292 osteoblast-like cells, K+ channel is sensitive to membrane tension, and may represent a unique adaptation of the bone cell membrane to mechanical stress.

국내에서 유행하는 HIV의 전파 경로에 따른 Subtype 분포

이주실,남정구,김성순,강춘,최병선,김옥진,박미선,성봉모,서순덕,전수경,변승옥,신영오,조해월 대한감염학회 2001 감염 Vol.33 No.5

Background : Previous data have been reported that subtype B is prevalent in South Korea, but neither the extent nor the proportion of subtypes could be evaluated. This study was designed to analyze the distribution of HIV-1 subtypes, temporal instructions and transmission dynamics between epidemiological groups. Methods : 1,280 Koreans had been diagnosed as HIV seropositive during the period 1985 to 2000. Among them, 134 individuals were selected for this molecular epidemiological study. 134 DNAs were isolated from uncultured or cultured peripheral blood mononuclear cells. V3-V5 (0.7 kb) fragment of HIV-1 env gene was amplified by nested polymerase chain reaction and was sequenced. Results : HIV-1 isolates from thirty-seven homosexuals were all subtype B (100%). On the other hand, 66 isolates from 94 heterosexuals were subtype B (70%) and 28 were non B subtypes (30% : 13 A, 4 C, 2 D, 8 E , 1 G). Only subtype B strains were isolated from 73 males who were infected with HIV inside Korea while 16 B and 20 non B subtype strains were isolated from 36 males who were HIV infected outside of Korea. However, B and non B strains were isolated half and half from females who were infected inside Korea except one. Conclusion : The HIV-1 subtype B strains are prevalent in Korea from the early HIV infection until present in both homo and heterosexuals. Non B strains have been transmitted from men who were infected outside Korea to their spouses and casual partners. So, we need further study to monitor subtype B and non B HIV transmission in epidemiological groups of Korea, (Korean J Infect Dis 33:311∼318, 2001)

여성 스포츠 소비자 증대를 위한 커뮤니케이션 형태 연구

이상봉,노영태,이영덕,전동호,박병주,박철준 釜山大學校 附設 體育科學硏究所 1997 體育科學硏究所 論文集 Vol.13 No.-

This study was executed in order to gauge the possibility of the strategy of marketing communication, which was for an increase of female consumer' participation in sports. It was conducted among a random sample of 1.346 women over the age of 18 in Pusan area, and its contents of survey was the shape of leisure activity and preferation of mass media, the aspects of their watching TV. 1. The form of leisure activity seemed to be most favoured as spectators.. Meanwhile sports-type leisure activity appeared to be more favoured by people out of work compared to people in work. 2. It was shown in the most people that they got the media of the use of commercial sports institution by their family or friends. 3. It was shown that female magazines was the most favoured among periodical magazines. 4. In daily newspapers, they prefer local one to central one. Meanwhile sports-newspaper was the worst favoured. 5. TV news was the most preferred, that is in case of the married against the unmarried. 6. It was the most shown that sports program was watched during suitable hours. But a few people answered that they hardly watch that. 7. It was shown that cultural program was watched generally during suitable hours, yet the unmarried scarcely watch that. 8. It was the most shown that comedy program was watched during suitable hours. But a few people answered that they hardly watch that. 9. It was the most shown that dramatic series and movie program were occasionally watched by them.

자동접종장치의 개발에 관한 연구

이병엽,조덕호 한밭대학교 산업과학기술연구소 1994 논문집 Vol.2 No.-

Inoculation is one of the important treatments in gray cast iron production. In spite of the fact that post inoculation is a treatment that should not be abbreviated, it is often abbreviated in many foundary shops and as the result many kinds of casting defects are occurring. In this study we made and efforts to develop automatic inoculation equipment in order to automatise the conventional manual inoculation. Principal abilities of this equipment are as follow. 1. Total feeds, feeding speed, feeding time, and total running time are indicated on LCD. 2. If feed and time are determined and inputted, speed and running time is calculated and indicated automatically. 3. If speed and time are determined and inputted, feed and running time is calculated and indicated by accumulation. 4. Automatic and munual operation are possible. 5. By the replacement of inoculant feeding disc, the amount of inoculant can be regulated form 1 to 120 gr/sec. 6. Owing to campact, set-up and movement of equipment are convenient and various inoculation can be applied ; ladle inoculation, stream inoculation, and so on…