• 한국자기학회지
• /
• 제15권1호
• /
• pp.12-16
• /
• 2005

본 연구에서는 비정질 시료 $Fe_{87}Zr_{7}B_{6}$ 에 중성자르 조사시킨 후 자기화의 온도의존성, X-ray 회절과 복소 투자율을 측정하여 중성자 조산 전, 후의 자기적 특성 변화를 보았으며, 다양한 중성자 조사량에 따른 복소 투자율과 자기이력곡선을 측정하여 측정하여 중성자 조사량에 따른 지구벽 운동과 자기화 회전을 보았다. 실험결과 중성자 조사에 의한 지구벽 운동은 감소하였으며, 자기화 회전은 증가 한 것을 볼 수 잇었다. 또한, 자기이완 주파수는 지구벽 운동의 경우 증가하였으며, 자기화 회전에 의한 이완 주파수는 감소하였다. 자기이력곡선의 결과 중성자 조사 후 포화 자기화 값이 감소하는 것을 볼 수 있었는데 이러한 실험 결과로부터 중성자 조사 후 생긴 결함에 의해 지구벽 운동은 억제되었으며, 자기화 회전부분은 증가 한 것을 알 수 있었다.

• 한국인터넷방송통신학회논문지
• /
• 제20권5호
• /
• pp.63-70
• /
• 2020

본 논문에서는 35 GHz 대역의 군 탐색기용 송수신 모듈을 설계 및 제작하였다. 밀리미터파 대역의 기판 성능과 집적도를 높이기 위해, 4층 액정 폴리머 기판을 개발하였다. 4층 액정 폴리머 기판은 3장의 FCCL 기판과 2장의 접착층으로 구현되었으며, 적층을 위해 기판간의 녹는 점 차이를 이용한 공정을 이용하였다. 스트립선로와 마이크로스트립 선로를 이용하여 기판의 길이에 따른 전송손실을 확인하였고, 35 GHz 대역의 전력분배기를 통해 액정폴리머 기판의 성능을 검증하였다. 이러한 기판을 이용하여 전력증폭기와 저잡음증폭기와 같은 송수신모듈을 구성하는 개별 블록에 대한 성능을 확인한 후, 단일 채널 Ka대역 송수신모듈을 4층 액정 폴리머 기판을 이용하여 개발하였다. 제작한 송수신모듈의 송신출력은 펄스 Duty 10%에서 1.1W 이상, 수신 잡음지수는 8.5 dB 이하, 수신 이득은 17.6 dB 이상의 수신 특성을 갖는다.

• 생명과학회지
• /
• 제28권11호
• /
• pp.1277-1284
• /
• 2018

본 연구에서는 효모염색체내에 다양한 유전자 발현 cassette를 도입하기 위해 Cre/loxP system을 가진 repeated yeast integrative plasmid (R-YIp)를 구축하였다. R-YIp는 반복적으로 형질전환체를 선별할 수 있는 selective marker (CgTRP1)와 loxP 서열, 그리고 integration을 위한 목적서열을 함유하고 있어 같은 염색체의 동일한 위치에 여러 개의 유전자 발현 cassette를 도입하는 것이 가능하다. 따라서 xylan/xylose 대사에 관련된 endoxylanase (XYLP), ${\beta}$-xylosidase (XYLB), xylose reductase (GRE3) 그리고xylitol dehydrogenase (XYL2)의 효모염색체내에 도입을 시도하였다. 먼저 XYLP, XYLB, GRE3그리고 XYL2 유전자의 효율적인 발현을 위한 promoter를 선별하기 위해 pGMF-GENE과 pAMF-GENE plasmid를 구축하였고, 각 유전자들의 발현에 GAL10 promoter가 적합함을 확인하였다. 다음으로 GAL10p-GENE-GAL7t cassette를 가진 pRS-GENE plasmid (R-YIp)를 구축하여, 반복적 integration 과정과 selective marker의 제거를 통해 각각의 R-YIps를 효모 7번염색체에 순차적으로 도입하였다. R-YIp system을 통해 효모염색체내에 도입된 유전자들은 모두 안정적으로 발현되었고, 활성형의 재조합효소를 생산함을 확인할 수 있었다. 따라서 다수의 외래유전자를 효모염색체내 도입함에 있어 selective marker와 숙주세포 선택의 한계를 R-YIp system을 통해 어느 정도 극복할 수 있을 것이라 기대한다.

• Ocean Systems Engineering
• /
• 제4권2호
• /
• pp.83-97
• /
• 2014

Wave propagation in a three-dimensional (3D) fully nonlinear numerical wave tank (NWT) is studied based on velocity potential theory. The governing Laplace equation with fully nonlinear boundary conditions on the moving free surface is solved using the indirect desingularized boundary integral equation method (DBIEM). The fourth-order predictor-corrector Adams-Bashforth-Moulton scheme (ABM4) and mixed Eulerian-Lagrangian (MEL) method are used for the time-stepping integration of the free surface boundary conditions. A smoothing algorithm, B-spline, is applied to eliminate the possible saw-tooth instabilities. The artificial wave speed employed in MTF (multi-transmitting formula) approach is investigated for fully nonlinear wave problem. The numerical results from incorporating the damping zone (DZ), MTF and MTF coupled DZ (MTF+DZ) methods as radiation condition are compared with analytical solution. An effective MTF+DZ method is finally adopted to simulate the 3D linear wave, second-order wave and irregular wave propagation. It is shown that the MTF+DZ method can be used for simulating fully nonlinear wave propagation very efficiently.

• 대한안전경영과학회지
• /
• 제5권2호
• /
• pp.129-143
• /
• 2003

Bsusiness-to- Business transactions requires interactions between diverse application s and business. This gives rise to the need to for a common standard and protocol for exchanging busienss messages. and RosettaNet is the leading industry organization focused on developing B2B process standard for a global supply chain. This paper is intended as an investigation of Build-up Method of SCM Connection applying EC Standard(Rossetta-net) to reduce the integration effort, and improve extensibility and interoperability of an eBusiness infrastructure.-Intiative way for E-commerce applications to quickly incorporate new standards. Supply Chain Management (SCM) helps companies plan and execute supply to meet customer demand. The researches of modem scientists have thrown new light on the subject. but, The study of SCM for EC Standard has been strangely neglected by critics. Consequently, existing SCM system, which require to introduce the functions of EC, needs to be changed. Let me summarize the main points that have been made in this paper. The sharing information for connection and the Rosetta-net standard of the existing SCM system, and PIP 3A4, order management module, of the Rosetta-net specifications for connection by the Rosetta-net. Lastly, That shows the process of the gateway for connecting among the existing SCM systems. This provides felxibility in incorporating any new emerging open standard.

• JSTS:Journal of Semiconductor Technology and Science
• /
• 제14권4호
• /
• pp.443-450
• /
• 2014

This paper presents a 20-Gb/s optical receiver circuit fabricated with standard 65-nm CMOS technology. Our receiver circuits are designed with consideration for parasitic inductance and capacitance due to bonding wires connecting the photodetector and the circuit realized separately. Such parasitic inductance and capacitance usually disturb the high-speed performance but, with careful circuit design, we achieve optimized wide and flat response. The receiver circuit is composed of a transimpedance amplifier (TIA) with a DC-balancing buffer, a post amplifier (PA), and an output buffer. The TIA is designed in the shunt-feedback configuration with inductive peaking. The PA is composed of a 6-stage differential amplifier having interleaved active feedback. The receiver circuit is mounted on a FR4 PCB and wire-bonded to an equivalent circuit that emulates a photodetector. The measured transimpedance gain and 3-dB bandwidth of our optical receiver circuit is 84 $dB{\Omega}$ and 12 GHz, respectively. 20-Gb/s $2^{31}-1$ electrical pseudo-random bit sequence data are successfully received with the bit-error rate less than $10^{-12}$. The receiver circuit has chip area of $0.5mm{\times}0.44mm$ and it consumes excluding the output buffer 84 mW with 1.2-V supply voltage.

• Journal of Microbiology and Biotechnology
• /
• 제24권3호
• /
• pp.371-378
• /
• 2014

The aim of the present study was to investigate the antigenotoxic properties of the probiotic Lactobacillus rhamnosus IMC501; DNA damage was induced by one representative food mutagen, 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP). Mice were treated orally with suspensions of lactobacilli for 10 days before administration of food mutagen. During the treatment, the abundance of lactobacilli in feces, as assessed by qPCR analysis, increased, whereas ${\beta}$-glucuronidase and N-acetyl-${\beta}$-glucosaminidase activities decreased. The extent of DNA damage was measured in colon and liver cells by comet assay. In colonocytes, diet supplementation with IMC501 resulted in a significant inhibition of DNA damage induced by PhIP. The results obtained in this in vitro study suggest that Lactobacillus rhamnosus IMC501 used as a dietary supplement can provide a useful integration of antimutagen food components of the normal diet, which are generally lower than the protective level.

• ETRI Journal
• /
• 제43권2호
• /
• pp.260-271
• /
• 2021

This paper addresses Very large-scale integration (VLSI) placement optimization, which is important because of the rapid development of VLSI design technologies. The goal of this study is to develop a hybrid algorithm for VLSI placement. The proposed algorithm includes a sequential combination of a genetic algorithm and an evolutionary algorithm. It is commonly known that local search algorithms, such as random forest, hill climbing, and variable neighborhoods, can be effectively applied to NP-hard problem-solving. They provide improved solutions, which are obtained after a global search. The scientific novelty of this research is based on the development of systems, principles, and methods for creating a hybrid (combined) placement algorithm. The principal difference in the proposed algorithm is that it obtains a set of alternative solutions in parallel and then selects the best one. Nonstandard genetic operators, based on problem knowledge, are used in the proposed algorithm. An investigational study shows an objective-function improvement of 13%. The time complexity of the hybrid placement algorithm is O(N2).

• JSTS:Journal of Semiconductor Technology and Science
• /
• 제1권3호
• /
• pp.141-157
• /
• 2001

Highly reliable packaged 64kbit ferroelectric memories with $0.8{\;}\mu\textrm{m}$ CMOS ensuring ten-year retention and imprint at 125^{\circ}C$ have been successfully developed. These superior reliabilities have resulted from steady integration schemes free from the degradation, due to layer stress and attacks of process impurities. The resent results of research and development for ferroelectric memories at Hynix Semiconductor Inc. are summarized in this invited paper.

• 한국양식학회지
• /
• 제16권1호
• /
• pp.51-58
• /
• 2003

The first Indian transgenic fish was generated in 1991 using borrowed constructs from foreign sources. To construct transformation vectors for the indigenous fishes, growth hormone genes of rohu (r-CH), Labeo rohita and catfish, Heteropneustes fossilis were isolated, cloned and sequenced; their fidelity was confirmed in prokaryotic and eukaryotic systems. A vector was constructed with grass carp b-actin promoter driving the expression of r-GH. Rohu eggs are large. fragile and swell 2~3 times. when fertilized. Hence they were amenable only for electroporated sperm-mediated gene transfer. Accordingly, the sperm electroporation technique was standardized to ensure 25% hatchling survival and 37% Presumptive transgenics without suffering any deformity. Southern analysis confirmed genomic integration in 15% of the tested individuals (Ti) belonging to family lines 2 and 3: another 25% of the Juveniles (Te) were also proved transgenic but with the transgene persisting extrachromosomally for longer than 1 to 2 years. perhaps due to the presence of replicon in the vector. Transgenics belonging to different family lines grew 6~8 times faster than the respective controls. Difference in growth trends of Ti and Te within a family line was not significant. In the Ti family 3 remarkable growth acceleration was sustained for a period longer than 36 weeks but in those of family 2, it gradually decreased. All transgenic fishes including the rohu converted the food at a significantly higher efficiency. Barring the transgenic mudloach, all the other transgenic fishes consumed food at significantly reduced rate.