• Title/Summary/Keyword: pK

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Molecular Cloning and Expression of a Xylanase Gene from Thermophilic Alkalophilic Bacillus sp. K-17 in Escherichia coli (고온, 호알칼리성 Bacillus sp. K-17 Xylanase 유전자의 Escherichia coli 에의 클로닝 및 발현)

  • Sung, Nack-Kie;Chun, Hyo-Kon;Shim, Ki-Hwan;Kang, In-Soo;Teruhiko Akiba
    • Microbiology and Biotechnology Letters
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    • v.17 no.3
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    • pp.178-182
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    • 1989
  • A gene coding for a xylanase of thermophilic alkalophilic Bacillus sp. K-17 was cloned in Escherichia coli C600 with pBR322. Plasmid pAXl13 was isolated from a transformant producing xylanase, and the xylanase gene was located in a 4.3 Kb HindIII fragment. Biotinylated pAXl13 hybridized to a 4.3 Kb HindIII fragment from chromosomal DNA of thermophilic alkalophilic Bacillus sp. K-17. The xylanase activity was observed in the extracellular curture fluid of E. coli carrying pAXl13. The pAXl13-encoded xylanase had the same enzymatic properties as those of xylanase I produced by thermophilic alkalophilic Bacillus sp. K-17.

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Loss of Heterozygosity at 3p in Korean Non-Small Cell Lung Cancer (한국인 비소세포폐암에서의 3p의 소실)

  • Lee, Choon-Taek;Kim, Mi-Hee;Park, Kyung-Ho;Park, Jong-Ho;Baek, Hee-Jong;Zo, Jae-Ill;Kim, Jin-Kyoo;Kim, Chang-Min
    • Tuberculosis and Respiratory Diseases
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    • v.45 no.5
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    • pp.975-983
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    • 1998
  • Purpose: Frequent deletion of 3p in numerous cancer including lung cancer suggests the presence of tumor suppressor gene. 3p has been analysed by RFLP and PCR-LOH of microsatellite locus. In this study, we observed the deletion of 3p in Korean NSCLC by PCR-LOH of 4 microsatellite loci and investigated the clinical significance. Method: 62 surgically resected NSCLC DNA and normal lung DNA have been analysed by PCR-LOH at three dinucleotide[D3S1228 (3p14.1-14.3), D3S1067 (3p14.3-21.1), D3S1029 (3p21.1-21.3)] and one tetranucleotide[D3S1537 (3p 22-24.2)] repeat microsatellite loci. Results: Among 59 informative cases, 3p deletion by PCR-LOH at four microsatellite loci was found in 31 patients(52.5%). 3p deletion were found in 55% of squamous cell lung cancer and 47% of adenocarcinoma patients. No significant difference has been found in clinical parameters such as staging, smoking and survival according to the status of 3p deletion. Conclusion: Deletions in 3p have played an important role in Korean NSCLC though no clinical significance was detected.

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P2P traffic Detecion and QoS Control Algorithm based Passive Monitoring (Passive Monitoring 기반의 P2P 트래픽 탐지 및 QoS 제어기법)

  • Kim, Hee-Joon;Han, Min-Kyu;Sung, Baek-Dong;Hong, Jin-Pyo
    • Proceedings of the Korean Information Science Society Conference
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    • 2007.06d
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    • pp.477-482
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    • 2007
  • 최근 다양한 P2P 프로그램을 많이 사용함에 따라 네트워크에서 생겨나는 트래픽의 상당 부분이 P2P가 발생시키는 트래픽으로 이미 HTTP, FTP의 양을 훨씬 뛰어넘고 있다. 현재 인터넷 환경에서 방화벽을 통과하기 위해 포트번호를 변경하여 통신을 하는 새로운 P2P응용들의 행동들은 전통적인 well-known port 기반의 응용프로그램을 구분하는 단순한 분석 방법만으로 신뢰하기가 어렵다. 새로운 P2P 응용들과 같은 트래픽 모니터링의 정확도를 높이기 위해서는 TCP/IP 헤더만이 아니라 패킷이 담고 있는 페이로드 내용에 대한 조사 차원의 모니터링 방법이 필요하다. 본 논문에서는 TCP/IP 헤더 정보와 더불어 패킷의 페이로드 내용을 조사하여 P2P 트래픽을 탐지하는 모니터링 기법을 제안한다. 이어 탐지되는 P2P 트래픽에 대하여 Linux Netfilter Framework의 Queuing Discipline에서 제공하는 계층적인 우선순위 큐를 사용하여 일정한 양의 대역폭을 할당하는 정책을 적용함으로써 안정적이면서 효율적인 네트워크 운용 방안을 제시한다.

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SOME EXTENSION RESULTS CONCERNING ANALYTIC AND MEROMORPHIC MULTIVALENT FUNCTIONS

  • Ebadian, Ali;Masih, Vali Soltani;Najafzadeh, Shahram
    • Bulletin of the Korean Mathematical Society
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    • v.56 no.4
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    • pp.911-927
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    • 2019
  • Let $\mathscr{B}^{{\eta},{\mu}}_{p,n}\;({\alpha});\;({\eta},{\mu}{\in}{\mathbb{R}},\;n,\;p{\in}{\mathbb{N}})$ denote all functions f class in the unit disk ${\mathbb{U}}$ as $f(z)=z^p+\sum_{k=n+p}^{\infty}a_kz^k$ which satisfy: $$\|\[{\frac{f^{\prime}(z)}{pz^{p-1}}}\]^{\eta}\;\[\frac{z^p}{f(z)}\]^{\mu}-1\| <1-{\frac{\alpha}{p}};\;(z{\in}{\mathbb{U}},\;0{\leq}{\alpha}<p)$$. And $\mathscr{M}^{{\eta},{\mu}}_{p,n}\;({\alpha})$ indicates all meromorphic functions h in the punctured unit disk $\mathbb{U}^*$ as $h(z)=z^{-p}+\sum_{k=n-p}^{\infty}b_kz^k$ which satisfy: $$\|\[{\frac{h^{\prime}(z)}{-pz^{-p-1}}}\]^{\eta}\;\[\frac{1}{z^ph(z)}\]^{\mu}-1\|<1-{\frac{\alpha}{p}};\;(z{\in}{\mathbb{U}},\;0{\leq}{\alpha}<p)$$. In this paper several sufficient conditions for some classes of functions are investigated. The authors apply Jack's Lemma, to obtain this conditions. Furthermore, sufficient conditions for strongly starlike and convex p-valent functions of order ${\gamma}$ and type ${\beta}$, are also considered.

A comparative investigation of pH-sensing properties of LPCVD $Si_3N_4$ sensors configured in three different structures (세 가지 다른 구조로 제작된 LPCVD $Si_3N_4$ 센서 소자의 pH 감지특성의 비교분석)

  • Shin, Paik-Kyun;Lee, Neung-Heon;Im, Heon-Chan;Kim, Jin-Sik;Park, Kang-Sik;Cho, Ki-Seon;Lee, Duck-Chool
    • Proceedings of the KIEE Conference
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    • 2004.07c
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    • pp.1694-1696
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    • 2004
  • $Si_3N_4$ 박막을 동일한 공정 파라메터로 저압 화학기상증착법(LPCVD)으로 증착하고, IS, LOCOS- IS 및 ISFET의 세 가지 각각 다른 구조로 하여 용약 중 pH 농도 감지용 센서소자를 제작하였다. 이 세 가지 다른 센서소자에 대하여 pH 농도변화에 따른 감지도, 감지특성곡선의 선형성, 히스테리시스 등 주요 특성을 각각 조사한 후 비교 분석하였다. LOCOS-IS 구조의 pH 센서는 ISFET 구조의 pH 센서와 유사한 우수한 제반 pH 감지특성을 보였으나, 간단한 IS 구조의 pH 센서는 이들에 비해 상대적으로 열악한 pH 감지특성을 보였다. 동일공정으로 제작된 Si3N4 박막으로 제작되었음에도 불구하고 간단한 IS 구조의 pH 센서의 비교적 열악한 특성을 보이는 원인을 규명하기 위하여, pH 농도 변화에 따른 C-V특성 변화에 의한 pH 감지특성 조사시의 IS 및 LOCOS-IS 구조의 정전용량의 변화를 비교하고 고찰하였다.

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Low Specific On-resistance SOI LDMOS Device with P+P-top Layer in the Drift Region

  • Yao, Jia-Fei;Guo, Yu-Feng;Xu, Guang-Ming;Hua, Ting-Ting;Lin, Hong;Xiao, Jian
    • JSTS:Journal of Semiconductor Technology and Science
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    • v.14 no.5
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    • pp.673-681
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    • 2014
  • In this paper, a novel low specific on-resistance SOI LDMOS Device with P+P-top layer in the drift region is proposed and investigated using a two dimensional device simulator, MEDICI. The structure is characterized by a heavily-doped $P^+$ region which is connected to the P-top layer in the drift region. The $P^+$ region can modulates the surface electric field profile, increases the drift doping concentration and reduces the sensitivity of the breakdown voltage on the geometry parameters. Compared to the conventional D-RESURF device, a 25.8% decrease in specific on-resistance and a 48.2% increase in figure of merit can be obtained in the novel device. Furthermore, the novel $P^+P$-top device also present cost efficiency due to the fact that the $P^+$ region can be fabricated together with the P-type body contact region without any additional mask.

Kinetics Studies on the Mechanism of Hydrolysis of S-Phenyl-S-vinyl-N-p-tosylsulfilimine Derivatives

  • Pyun, Sang-Yong;Kim, Tae-Rin;Lee, Chong-Ryoul;Kim, Whan-Gi
    • Bulletin of the Korean Chemical Society
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    • v.24 no.3
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    • pp.306-310
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    • 2003
  • Hydrolysis reactions of S-phenyl-S-vinyl-N-p-tosylsulfilimine (VSI) and its derivatives at various pH have been investigated kinetically. The hydrolysis reactions produced phenylvinylsulfoxide and p-toluene sulfonamide as the products. The reactions are first order and Hammett ρ values for pH 1.0, 6.0, and 11.0 are 0.82, 0.45, and 0.57, respectively. This reaction is not catalyzed by general base. The plot of k vs pH shows that there are three different regions of the rate constants $(k_t)$ in the profile.; At pH < 2 and pH > 10, the rate constants are directly proportional to the concentrations of hydronium and hydroxide ion catalyzed reactions, respectively. The rate constant remains nearly the same at 2 < pH < 10. On the bases of these results, the plausible hydrolysis mechanism and a rate equation have been proposed: At pH < 2.0, the reaction proceeds via the addition of water molecule to sulfur after protonation at the nitrogen atom of the sulfilimine, whereas at pH > 10.0, the reaction proceeds by the addition of hydroxide ion to sulfur directly. In the range of pH 2.0-10.0, the addition of water to sulfur of sulfilimine appears to be the rate controlling step.

Efficient Peer-to-Peer File Sharing Using Network Coding in MANET

  • Lee, Uichin;Park, Joon-Sang;Lee, Seung-Hoon;Ro, Won-W.;Pau, Giovanni;Gerla, Mario
    • Journal of Communications and Networks
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    • v.10 no.4
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    • pp.422-429
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    • 2008
  • Mobile peer-to-peer (P2P) systems have recently got in the limelight of the research community that is striving to build efficient and effective mobile content addressable networks. Along this line of research, we propose a new peer-to-peer file sharing protocol suited to mobile ad hoc networks (MANET). The main ingredients of our protocol are network coding and mobility assisted data propagation, i.e., single-hop communication. We argue that network coding in combination with single-hop communication allows P2P file sharing systems in MANET to operate in a more efficient manner and helps the systems to deal with typical MANET issues such as dynamic topology and intermittent connectivity as well as various other issues that have been disregarded in previous MANET P2P researches such as addressing, node/user density, non-cooperativeness, and unreliable channel. Via simulation, we show that our P2P protocol based on network coding and single-hop communication allows shorter file downloading delays compared to an existing MANET P2P protocol.

Improved Breakdown Voltage Characteristics of $In_{0.5}Ga_{0.5}P/In_{0.22}Ga_{0.78}As/GaAs$ p-HEMT with an Oxidized GaAs Gate

  • I-H. Kang;Lee, J-W.;S-J. Kang;S-J. Jo;S-K. In;H-J. Song;Kim, J-H.;J-I. Song
    • JSTS:Journal of Semiconductor Technology and Science
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    • v.3 no.2
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    • pp.63-68
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    • 2003
  • The DC and RF characteristics of $In_{0.5}Ga_{0.5}P/In_{0.22}Ga_{0.78}As/GaAs$ p-HEMTs with a gate oxide layer of various thicknesses ($50{\;}{\AA},{\;}300{\;}{\AA}$) were investigated and compared with those of a Schottky-gate p-HEMT without the gate oxide layer. A prominent improvement in the breakdown voltage characteristics were observed for a p-HEMT having a gate oxide layer, which was implemented by using a liquid phase oxidation technique. The on-state breakdown voltage of the p-HEMT having the oxide layer of $50{\;}{\AA}$was ~2.3 times greater than that of a Schottky-gate p-HEMT. However, the p-HEMT having the gate oxide layer of $300{\;}{\AA}$ suffered from a poor gate-control capability due to the drain induced barrier lowering (DIBL) resulting from the thick gate oxide inspite of the lower gate leakage current and the higher on-state breakdown voltage. The results for a primitive p-HEMT having the gate oxide layer without any optimization of the structure and the process indicate the potential of p-HEMT having the gate oxide layer for high-power applications.

Nucleotide Sequence Analyses of p10 Gene and its Promoter of Hyphantria cunea Nuclear Polyhedrosis Virus (Hyphantria cunea Nuclear Polyhedrosis Virus p10유전자와 프로모터의 염기서열 결정)

  • Park, Sun-A;Cha, Sung-Chul;Chang, Jae-Hyeok;Lee, Hyung-Hoan
    • The Journal of Korean Society of Virology
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    • v.26 no.1
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    • pp.131-137
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    • 1996
  • The sequences of p10 gene its promoter of Hyphantria cunea NPV were determined. According to the sequence analysis, the putative p10 gene ORF has 285 bp. The 5'-non-coding leader sequence of the p10 gene promoter contained the TATA box and the putative transcription initiation site TAAG motif. Poly (A) tail signals, AATAAA sequence was at site 65 base upstream from the 3' terminus. The deduced amino acid sequence of p10 protein was 95 with a predicted molecular weight of 10.26 kDa. In the p10 protein sequence, a hydrophobic region was present at the N-terminus of the protein, whereas the C-terminus was highly hydrophilic. The p10 protein of H. cunea NPV did not contain cysteine, histidine, trytophan, tryptophane, tyrosine, glutamine and asparagine residues.

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