마늘이 개의 조직내 카드뮴축적 및 혈액상에 미치는 영향

이병제,성은주,이미순,장인호,이현범,Lee, Byung-je,Sung, Eun-ju,Lee, Mi-soon,Jang, In-ho,Lee, Hyun-beom 대한수의학회 1994 大韓獸醫學會誌 Vol.34 No.3

The environmental pollution by heavy metals has become a significant hygenic problem. Recently it is said the garlic supplementation in diet have protective effect on the heavy metal accumulation in tissue of rat by a researcher. In this study two experiments were undertaken. Firstly, dogs were fed diet supplemented with cadmium of cadmium plus 7% of raw garlic for 50 days. on the 50th day of experiment all dogs were euthanasied and the cadmium content of various tissue were measured by atomic absorption spectrophotometeric method. Secondly, in order to find out the toxic effect of garlic dogs were fed diet supplemented with 7% of raw garlic for 50 days and hematological or hematochemical observations were undertaken at 10 day intervals. The results obtained from these experiments were summarized as follows; 1. In dogs treated with cadmium and cadmium plus garlic cadmium was accumulated in renal cortex, liver, and muscle. However the concentrations of cadmium showed no significant between the two group. 2. In dogs fed diets supplemented with 7% of raw garlic significant decrease of erythrocyte count, packed cell volume and hemoglobin content and significant increase of Heinz body erythrocyte and reticulocyte count were recognized. 3. The garlic-treated dogs and control dogs had normal asparate aminotransferase, alanine aminotransferase, alkaline phosphotase, blood urea nitrogen value. The value showed no significant difference between the two group. 4. From these results it may be concluded that the garlic have protective effect for cadmium accmulation in tissue and excess garlic in diet could induce hemolytic anemia in dogs.

마이크로스트립 패치 안테나의 효율적 소형화 기법

이병제,이호준,강기조,김남영,이종철,김종환 한국전자파학회 2000 한국전자파학회논문지 Vol.11 No.6

본 논문은 tpo로이 제안된 안테나 소형화 기법을 이용하여 비교적 높은 이득과 광대역 특성을 지닌 마이크로 스트립 패치 안테나 (microstri patch antenna)를 개구 결합성 급전구조 (aperture coupled feed)를 이용하여 셀룰러 대역의 (824~894MHz) 중계기용으로 설계 및 제작되었다. 새로이 제안된 방법에서는 안테나의 크기를 줄이기 위하여 구형 마이크로스트립 패치 아테나의 TM01 모드의 전계분포를 이용하여 전계분포가 가장 큰 패치의 가장자리 아랫부분에 공진 패치의 길이 방향으로 유전체를 상빙하여 안테나의 크기를 효율적으로 줄이고 유전율이 높아짐으로써 발생되는 안테나의 이득 감소를 최소화 시킴과 동시에 소형 경량의 안테나를 쉽게 제작할수 있도록 설계 제작하였다. 또한 under-coupling 기법과 정합회로를 사용하여 셀룰러대역의 전대역에서 제작할 수 있도록 제작하였다. 또한 under-coupling 기법과 정합회로를 사용하여 셀룰러대역의 전 대역에서 VSWR이 1,5:1 이하가 되도록 설계하였다. 안테나 설계 툴 (Tool)은 Agilent Technologies사의 HFSS를 사용하였다. In this paper, using newly proposed size reduction technique, the aperture coupled microstrip patch antenna for a repeater system in a mobile communication cellular band (824~849 MHz) is developed with a wide bandwidth, small size, light weight, and low cost. The resonant frequency of microstrip antennas is related to the electric field distribution of the radiating patch. The field strength of $TM_{01}$ mode of a rectangular patch antenna is strongest at each of the extremities of the radiating patch, but negligible at center. Therefore, the size of a patch antenna can be effectively minimized by inserting the narrow rectangular dielectric into just under the edges of the resonant Patch. This Paper also proposes the bandwidth improvement technique by using under-coupling technique with a tuning stub. The VSWR is less than 1.5 : 1 for the whole cellular band. The simulation tool was HFSS, Agilent Technologies, Inc.

국부발진기에서의 누설신호의 새로운 제거방식

이병제,강기조 한국전자파학회 2000 한국전자파학회논문지 Vol.11 No.2

RF(radio frequency) 시스템의 송신탄을 설계할 때 고려해야 할 중요한 요소 중의 하나인 EMI(Electro magnetic interference)의 규격시험에서 항상 문제시되는 것이 송신기의 출력 스펙트럼에서 나타나는 불요 신호(Spurious interference) 이다. 이 불요 성분들 중 특히 문제가 되고 있는 것이 국부발진기(LO; Local oscillator)로부터 누설되는 LOL(Local oscillator leakage) 성분이다. 이 LOL성분은 국부발진기에서 누설(leakage)되어 RF단의 증폭기를 통하여 증폭되어 최종 출력에서 매우 높은 선호의 크기로 나타난다. 일반적으로 LOL을 제거하기 위해 서 너치필터(Notch filter) 또는 대역통과필터 (Band pass filter)를 사용해왔다. 본 논문에서는 국부발진기로부터 누설되는 불요 성분, 즉 LOL성분을 제거하는 방법으로 LOL과 동일한 크기를 가지고 위상 차이가 $180^{\circ}$인 신호를 국부발전기의 출력에서 만들어 믹서( Mixer)의 출력단에 더함으로써 LOL성분을 효과적으로 제거한다. 본 방 식을 무선랜(WLAN; Wireless 1$\infty$al area network) 시스템에 적용한 결과. 기존의 방식보다 30 dB 이상 LO 누설선호플 감쇄시킬 수 있었다 또한 본 방식은 RF 시스댐을 소형화 및 MMIC(Monolithic microwave integrated C circuit)화 할 경우 종전의 방법보다 효과적일 것으로 기대된다. One of the most important design parameters in a microwave radio transmitting system is to reduce spurious response from the output spectrum of the transmitting system. A Local oscillator (LO) is seldom totally pure and at the least contain some LO harmonic signals. A LO or any oscillator is a transmitter if provided with a suitable radiator, conduction, or leakage path. Where mixer is employed in the output of the LO mixer generated spurs can be increased by RF amplifier. To reduce LO leakage, notch filter or band pass filter has been conventionally used. In this paper, the leakage reduction(LR) signal, which has the same magnitude and the opposite phase with respect to LO leakage signal, is added to the output of mixer of the wireless LAN system. The LO leakage is reduced by 30 dB more than the conventional methods do. The proposed method is potentially suitable for low-cost, reliable, and simple application of monolithic microwave integrated circuits (MMICs)

안테나 기술 동향 및 개선점

이병제 한국전기전자재료학회 2000 전기전자재료 Vol.13 No.9

Organization of tRNA Genes in Aspergillus nidulans

이병제 한국유전학회 1986 Genes & Genomics Vol.8 No.1

To study on the organization and expression of eukaryotic tRNA gene, total tRNA genes of Aspergillus nidulans were cloned into E. coli. Of these clones, arginine-and aspartate-tRNA gene clone have been selected and the molecular structure of each tRNA genes has been determined. First of all, BamHl restriction endonuclease and T₄-DNA ligase were purified to establish the fundamental technique of recombinant DNA technology. The chromosomal DNA was obtained from haploid spores (conidia) by disrupting them physically and dye buoyant density gradient ultracentrifugation. pBR322 plasmid was used as a cloning vector. After in vitro recombination of Aspergillus-vector DNA using BamHl and T₄-DNA ligase, the recombinant DNAs were transformed into E. coli HB101. About 30,000 transformants were obtained from sixteen independent transformations. Among these, 5,300 colonies carrying Aspergillus DNA were selected by insertional inactivation. Colony hybridization experiments were performed with ^(32)P-labeled Aspergillus total tRNA, thus 105 clones of total tRNA gene have been selected from Aspergillus gene library. The results of clone analysis and cohybridization have revealed that tRNA genes of Aspergillus seem to be more clustered on the chromosome than those of yeast. Specific tRNAs of Aspergillus were identified either by charging test or by rapid RNA sequencing method. From charging test, the specific tRNAs such as tRNA^(Arg), tRNA^(Gly), tRNA^(Leu), tRNA^(Lys), and tRNA^(Val) were identified. With enzymatic partial digestion method using some specific RNases, tRNA^(Arg)_(ACG) and tRNA^(Asp)_(GUC) were identified and confirmed by further sequence analysis including identification of invariant bases and comparison of sequence homology. Modified bases of tRNA^(Arg) were analyzed by Silberklang's method. As a result, dihydrouracil, 5-methyluridine, 1-methylguanosine, and 2-methylguanosine were identified but 3 spots have not yet been identified. One of which is thought to be inosine. One clone (pANt32) showed positive signal when the total tRNA gene clones were hybridized with ^(32)P-labeled tRNA^(Arg) probe, and pANt12 responded with tRNA^(Asp) probe. Restriction map of these two plasmids have been made, and each tRNA genes were localized by Southern hybridization. Nucleotide sequences of each plasmids have been determined with Maxam and Gilbert's chemical cleavage methods. Each tRNA genes have been identified and tDNA sequences are coincide with the cognate RNA sequences. The most striking features of each tRNA gene are those that tRNA^(Asp) gene contains intervening sequences of 15 b.p. in which sequences complementary to anticodon sequences are not found and the long T-stretch is located just after the structural gene of tRNA^(Arg). In addition, the sequence homology of above two tRNAs to each tRNA family has been analyzed with computer. And the possible phylogenic relationship between species have also been deduced by comparing the nucleotide sequence homology of tRNA gene.

Characteristics of the Microstrip Antenna on a Biased Ferrite Substrate

Lee, Byungje 광운대학교 신기술연구소 1999 신기술연구소논문집 Vol.28 No.-

페라이트 기판으로 만들어진 마이크로스트립 안테나의 입력 임피던스 특성을 연구하였다. 입력 임피던스는 페라이트 기판으로부터 그린함수를 구한 다음 모멘트 방법을 사용해서 구할 수 있다. 바이어스제의 강도를 변화시키면서 마이크로스트립 안테나의 공진 주파수의 추이를 관찰하였다. 바이어스된 마이크로스트립 안테나의 레이더 단면적 에 대한 연구도 집중적으로 진행되었다. 본 논문에서 인가된 바이어스제의 방향은 페라이트 판과 수직일 경우와 평행할 경우이다. The characteristics of input impedance for a single microstrip fatch antenna on a biased ferrite substrate is studied. The input impedance is calculated by Method of Moments(MoM) where Green's function is formulated for ferrite substrate. The variation in resonant frequencies due to the changes in biasing strength is studied. The radar cross section(RCS) of a biased ferrite microstrip antenna was also an important part of this work. The biasing direction is normal(z) or in-plane(y) to the grounded ferrite substrate. The results come from the full-wave analysis by a computer simulation.

LTE 700 대역 기지국용 MIMO 마이크로스트립 패치 안테나 설계

김지훈,이병제 한국ITS학회 2011 한국ITS학회 학술대회 Vol.2011 No.1

DSRC 노변기지국용 MIMO 마이크로스트립 패치 안테나

이종현,이병제 한국ITS학회 2010 한국ITS학회 학술대회 Vol.2010 No.1

Wideband Antenna for High-Frequency 5G Wireless Communication

김익환,이병제 한국전자파학회 2022 Journal of Electromagnetic Engineering and Science Vol.22 No.3

In this study, a wideband patch array antenna for high-frequency 5G wireless communication is proposed. The wideband high-frequency 5G antenna is needed to handle the increase in 5G data traffic. The proposed antenna, a 2 × 16 element array with gap-coupled parasitic elements and a multi-section or stepped transformer feeding network with feed cover to prevent unwanted feed radiation, can cover 5G new radio (NR) n257 (26.5–29.5 GHz), n258 (24.25–27.5 GHz), and n261 (27.5–28.35 GHz) bands. Using parasitic elements with a single substrate instead of cavity and stacked structures, a wide impedance bandwidth (dB magnitude of S₁₁ < –10) of 24.2% (23.75–32 GHz) is achieved. A high cross-polarization discrimination (XPD > 25.2 dB) is achieved using orthogonal dual polarization. The peak gain obtained is 18.69 dB.

광학 밴드 갭(Photonic Band Gap)구조를 이용한 고성능 안테나 기술 동향

박면주,이병제 한국통신학회 2002 정보와 통신 Vol.19 No.12