• Title/Summary/Keyword: pre-signal

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Design of X-Band High Efficiency 60 W SSPA Module with Pulse Width Variation (펄스 폭 가변을 이용한 X-대역 고효율 60 W 전력 증폭 모듈 설계)

  • Kim, Min-Soo;Koo, Ryung-Seo;Rhee, Young-Chul
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.23 no.9
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    • pp.1079-1086
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    • 2012
  • In this paper, X-band 60 W Solid-State Power Amplifier with sequential control circuit and pulse width variation circuit for improve bias of SSPA module was designed. The sequential control circuit operate in regular sequence drain bias switching of GaAs FET. The distortion and efficiency of output signals due to SSPA nonlinear degradation is increased by making operate in regular sequence the drain bias wider than that of RF input signals pulse width if only input signal using pulsed width variation. The GaAs FETs are used for the 60 W SSPA module which is consists of 3-stage modules, pre-amplifier stage, driver-amplifier stage and main-power amplifier stage. The main power amplifier stage is implemented with the power combiner, as a balanced amplifier structure, to obtain the power greater than 60 W. The designed SSPA modules has 50 dB gain, pulse period 1 msec, pulse width 100 us, 10 % duty cycle and 60 watts output power in the frequency range of 9.2~9.6 GHz and it can be applied to solid-state pulse compression radar using pulse SSPA.

Mycobacterium tuberculosis-induced Expression of Interleukin-1 Beta is Mediated Via Protein Kinase C Signaling Pathway

  • Cho, Jang-Eun;Lee, Kyung-Hong;Son, Sin-Jee;Park, Sang-Jung;Lee, Hye-Young;Kim, Yoon-Suk
    • Biomedical Science Letters
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    • v.16 no.2
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    • pp.119-122
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    • 2010
  • Interleukin-1${\beta}$ $(IL-1{\beta})$ is one of the key proinflammatory cytokines and it plays an important role for the antimycobacterial host defense mechanisms. In this study, we examined Mycobacterium tuberculosis (MTB)-stimulated induction of IL-1${\beta}$ and evaluated the associated signal transduction pathways. In PMA-differentiated THP-1 cells, MTB infection increased mRNA expression of IL-$1{\beta}$ in a dose-dependent manner. The expression of IL-1${\beta}$ mRNA began to be induced at 1.5 h after infection, and induced expression of IL-1${\beta}$ was retained for 48 h after MTB infection. The increase in expression of IL-1${\beta}$ caused by MTB was reduced in cells treated with Ro-31-8425 (an inhibitor of PK$C{\alpha}$, ${\beta}I$, ${\beta}II$, ${\gamma}$, ${\varepsilon}$) or PD98059 (an inhibitor of MEK1), meanwhile, pre-treatment with $G\ddot{o}6976$ (an inhibitor of $Ca^{2+}$ dependent PK$C{\alpha}$ and PK$C{\beta}I$) or Rottlerin (an inhibitor of PK$C{\delta}$) has no effect on MTB-induced expression of $IL-1{\beta}$ mRNA. These results show that the expression of $IL-1{\beta}$ mRNA caused by MTB may be mediated via MEK1 and PKC isoforms including PK$C{\beta}II$, $PKC{\gamma}$, or $PKC{\varepsilon}$. Further studies are required to determine whether other PKC isoforms $(PKC {\eta},\;{\theta},\;{\varepsilon},\;and\;{\lambda}/{\iota})$, except $PKC{\delta}$, $PKC{\alpha}$, and $PKC{\beta}I$, are also involved in $IL-1{\beta}$ mRNA expression after mycobacterial infection.

A Study of the Construction in order to 24/25 I-NRZI Modulator Designs for DVCR (DVCR용 24/25 I-NRZI 변조기의 설계를 위한 구조 고찰)

  • Park, Jong-Jin;Kook, Il-Ho;Kim, Eun-Won;Cho, Won-Kyung
    • Journal of the Institute of Electronics Engineers of Korea TE
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    • v.37 no.1
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    • pp.35-41
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    • 2000
  • This paper considers the consturction of 24/25 I-NRZI (Interleaved - Non Return to Zero Inverse) modulator designs for DVCR (Digital Video Cassette Recorder), and size of validity bit in order to store the amplitude value of square-wave and the standard data ( sine and cosine coefficients) at ROM Table that to acceptable the spectrum standard. The validity bit size of the standard data and the amplitude value of square-wave that to store at ROM Table are affected the size of pilot signal on the output spectrum, and the hardware size of modulator. At the designable 24/25 I-NRZI modulator, we simulated using random pattern (F0,F1,F2) that to verification the output data of the spectrum. Moreover, the resultant of the spectrum analysis, at the optimizing value, is 0.065 on the amplitude value of square-wave, and 3bit on the size of bit in order to store the standared data at ROM Table. In order to verify the hardware of designable 24/25 I-NRZI modulator, we perform to modeling of C-language firstly, and coding to Verilog HDL (Cadence Verilog XL) and synthesized using Synopsys (Library "Samsung KG75") tool as a base of spectrum results. In a foundation of this result, we are considered the size of hardware. In this paper, a considerable 24/25 I-NRZI modulator designable less than 10,000 gates as that is improved consturction as regards the path method of pre-coder etc, and able to application digital camcorders as now practical use.

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PSS Movement Prediction Algorithm for Seamless hando (휴대인터넷에서 seamless handover를 위한 단말 이동 예측 알고리즘)

  • Lee, Ho-Jeong;Yun, Chan-Young;Oh, Young-Hwan
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.43 no.12 s.354
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    • pp.53-60
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    • 2006
  • Handover of WiBro is based on 802.16e hard handover scheme. When PSS is handover, it is handover that confirm neighbor's cell condition and RAS ID in neighbor advertisement message. Serving RAS transmits HO-notification message to neighbor RAS. Transmiting HO-notification message to neighbor RAS, it occurs many signaling traffics. Also, When WiBro is handover, It occurs many packet loss. Therefore, user suffer service degradation. LPM handover is supporting seamless handover because it buffers data packets during handover. So It is proposed scheme that predicts is LPM handover and reserves target RAS with pre-authentication. These schemes occur many signaling traffics. In this paper, we propose PSS Movement Prediction to solve signaling traffic. Target RAS is decided by old data in history cache. When serving RAS receives HO-notification-RSP message to target RAS, target RAS inform to crossover node. And crossover node bicast data packet. If handover is over, target RAS forward data packet. Therefore, It reduces signaling traffics but increase handover success rate. When history cache success, It decrease about 48% total traffic. But When history cache fails, It increase about 6% total traffic

Effect of CD14, Toll-like receptors, cytoskeletal inhibitors and $NF-{\kappa}B$ inhibitor on MMP-8 release from human neutrophils induced by E. coli lipopolysaccharides. (E. coli lipopolysaccharides로 유도된 사람 호중구에서 CD14, Toll-like receptors, cytoskeletal inhibitors 그리고 $NF-{\kappa}B$ inhibitor가 MMP-8 분비에 미치는 영향)

  • Yang, Seung-Min;Kim, Tae-Il;Seol, Yang-Jo;Lee, Yong-Moo;Ku, Young;Chung, Chong-Pyoung;Han, Soo-Boo;Rhyu, In-Chul
    • Journal of Periodontal and Implant Science
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    • v.35 no.2
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    • pp.427-436
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    • 2005
  • Objective: MMP-8 is a neutrophil enzyme and its level increases in some inflammatory diseases, including periodontal disease. We knew that the lipopolysaccharide of E.coli(E-LPS) induced MMP-8 release from human neutrophils. E-LPS is known to induce the production and release of inflammatory cytokines through CD14, Toll-like receptor(TLR). In the present study, we investigated whether MMP-8 release by E-LPS is induced via CD14-TLR pathway and the cellular mechanism of MMP-8 release in human neutrophils. Material and methods: Human neutrophils were isolated from the peripheral blood of healthy donors and pre-incubated in medium containing antibodies against CD14, anti-TLR2 and anti-TLR4 or several inhibitors of microtubules and microfilaments and then incubated with E-LPS. The cells were treated TPCK and E-LPS simultaneously. The MMP-8amount in the culture medium was determined using ELISA. Results: E-LPS increased MMP-8release from neutrophils and its induction was inhibited by anti-CD14 and anti-TLR4 but not by anti-TLR2 antibodies. The inhibitors of microtubule and microfilament polymerization significantly decreased E-LPS-induced MMP-8release. TPCK inhibited E-LPS-induced MMP-8 release. Conclusion: These results suggest that MMP-8 release is induced by E-LPS via the CD14-TLR4 signal pathway in human neutrophils and may be depedent on microtubule and microfilament systems and $NF-{\kappa}B$ pathway.

Evaluation of Field Application of Portable Near Infrared Reflectance Spectrometer (NIRS) for Quality Evaluation of Italian Ryegrass Silages (신속한 이탈리안라이그라스 사일리지의 품질평가를 위한 소형 근적외선분광기(NIRS)의 현장 적용성 평가)

  • Park, Hyung-Soo;Lee, Sang-Hoon;Kim, Jong-Gun;Choi, Ki-Choon;Seo, Sung;Kim, Won-Ho;Lee, Hyo-Won;Lim, Young-Chul
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.31 no.4
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    • pp.415-422
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    • 2011
  • This study evaluated the feasibility of using a portable near infrared reflectance spectrometer working in the 900~1,600 nm range for the measurement of quality-related parameters (moisture, pH, Acid detergent fiber (ADF), Neutral detergent fiber (NDF), Crude protein (CP), lactic acid) in intact silage. The calibration result for the Phazir (handheld, Polychromix) was compared with the result for the Spectrastar (Lab. based, Unity). A total of 67 Italian ryegrass silages were used to build calibration models using different spectral signal pre-treatments and the partial least squares regression (PLS) method. The good calibration statistics in two instruments was obtained for moisture content of Italian ryegrass silages with over $R^2$ = 0.95. The Phazir spectrometer was less accurate in measuring of ADF, NDF and CP contents. The Spectrastar instrument yielded greater precision for pH and lactic acid content; statistic values were over $R^2$ = 0.82 and the standard error of calibration (SEC) = 0.21% and 0.24%. Thus, the NIR measurement of forage quality in the field by portable NIR analyzers was shown not to be feasible, but additional investigations are required to discern the key instrumental and operational parameters that may influence the portable NIR measurement.

A Study on Call Admission Control Scheme based on Multiple Thresholds in the CDMA System (CDMA시스템에서 다중 종류의 문턱치를 사용한 호 수락제어 기법에 대한 연구)

  • Piao, Shi-Gwon;Park, Yong-Wan
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.28 no.3A
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    • pp.129-139
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    • 2003
  • CAC is a very important issue in CDMA system in order to protect the required QoS(quality of service) and increase the system's capacity. In this paper, we proposed and analyzed a call admission control scheme using multiple thresholds, which can provide quick processing time and better performance. There are two effective thresholds used to decide call admission. One is the number of active users, and the other is the signal to interference ratio(SIR). If the threshold of active users are lower than the low number of users threshold, we accept the new call without any other conditions. Otherwise, we check the current SIR to guarantee the quality of our service. System then accepts the new call when the SIR satisfies system requirement. Otherwise, the call will be rejected. Multiple threshold schemes are investigated and their performance is compared with the number of user and power based CAC's. simulation results are provided to evaluate the performance.

Immunological Characterization of Full and Truncated Recombinant Clones of ompH(D:4) Obtained from Pasteurella multocida (D:4) in Korea

  • Kim, Young-Hwan;Cheong, Ki-Young;Shin, Woo-Seok;Hong, Sung-Youl;Woo, Hee-Jong;Kwon, Moo-Sik
    • Journal of Microbiology and Biotechnology
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    • v.16 no.10
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    • pp.1529-1536
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    • 2006
  • We cloned a gene of ompH(D:4) from pigs infected with P. multocida D:4 in Korea [16]. The gene is composed of 1,026 nucleotides coding 342 amino acids (aa) with a signal peptide of 20 aa (GenBank accession number AY603962). In this study, we analyzed the ability of the ompH(D:4) to induce protective immunity against a wild-type challenge in mice. To determine appropriate epitope(s) of the gene, one full and three different types of truncated genes of the ompH(D:4) were constructed by PCR using pET32a or pRSET B as vectors. They were named ompH(D:4)-F (1,026 bp [1-1026] encoding 342 aa), ompH(D:4)-t1 (693 bp [55-747] encoding 231 aa), ompH(D:4)-t2 (561 bp [187-747] encoding 187 aa), and ompH(D:4)-t3 (540 bp [487-1026] encoding 180 aa), respectively. The genes were successfully expressed in Escherichia coli BL21(DE3). Their gene products, polypeptides, OmpH(D:4)-F, -t1, -t2, and -t3, were purified individually using nickel-nitrilotriacetic acid (Ni-NTA) affinity column chromatography. Their $M_rs$ were determined to be 54.6, 29, 24, and 23.2 kDa, respectively, using SDS-PAGE. Antisera against the four kinds of polypeptides were generated in mice for protective immunity analyses. Some $50{\mu}g$ of the four kinds of polypeptides were individually provided intraperitoneally with mice (n=20) as immunogens. The titer of post-immunized antiserum revealed that it grew remarkably compared with pre-antiserum. The lethal dose of the wild-type pathogen was determined at $10{\mu}l$ of live P. multocida D:4 through direct intraperitoneal (IP) injection, into post-immune mice (n=5, three times). Some thirty days later, the lethal dose ($10{\mu}l$) of live pathogen was challenged into the immunized mouse groups [OmpH(D:4)-F, -t1, -t2, and -t3; n=20 each, two times] as well as positive and negative control groups. As compared within samples, the OmpH(D:4)-F-immunized groups showed lower immune ability than the OmpH(D:4)-t1, -t2, and -t3. The results show that the truncated-OmpH(D:4)-t1, -t2, and -t3 can be used for an effective vaccine candidate against swine atrophic rhinitis caused by pathogenic P. multocida (D:4) isolated in Korea.

Perceptions of Hospital Health Information Managers Regarding Present on Admission Indicators in Korea: A Qualitative Study (입원 시 상병의 수집 및 활용에 관한 보건의료정보관리사의 관점: 질적 연구)

  • Pyo, Jee-Hee;Choi, Eun-Young;Oh, Hae-Mi;Lee, Won;Kim, Ju-Young;Ock, Min-Su;Kim, So-Yoon;Lee, Sang-Il
    • Quality Improvement in Health Care
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    • v.26 no.1
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    • pp.23-34
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    • 2020
  • Purpose: This qualitative study was conducted to examine the current status and problems concerning the collection of present on admission (POA) indicators and determine how to use these indicators for evaluating the quality of care and degree of patient safety. Methods: A total of 11 health information managers were divided into two groups according to the size of their hospitals. Two focus group discussions (FGDs) were conducted, one for each group, which followed a pre-developed semi-structured guideline. The verbatim transcriptions of the FGDs were analyzed. Results: The majority of participants were concerned about entering POA flags honestly because they did not know how future POA indicators would be used. In particular, for some participants, POA N was a burden that could imply a signal of mismanagement within the medical institution. In addition, the lack of awareness and indifference of physicians regarding POA indicators were some of the difficulties for POA flag entry. Although medical institutions are making efforts to improve the accuracy of POA flagging, many participants mentioned the need to develop real case-oriented POA entry guidelines to improve the accuracy of POA flagging. Conclusion: To increase the validity of POA indicators, it is necessary to increase the level of awareness of POA indicators in physicians and other medical professionals. Furthermore, efforts related to POA indicators by individual medical institutions need to be reflected in the process evaluation.

Anti-Inflammatory Effect of Hot Water Extract of Aronia Fruits in LPS-Stimulated RAW 264.7 Macrophages (LPS 자극 RAW 264.7 대식세포에 있어서 아로니아 열매 열수 추출물의 항염증 효과)

  • Yang, Hui;Oh, Kwang-Hoon;Yoo, Yung Choon
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.44 no.1
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    • pp.7-13
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    • 2015
  • In this study, anti-inflammatory activity of hot water extract of Aronia fruits (AF-H) was examined. Pre-treatment with AF-H significantly inhibited production of nitric oxide (NO) and prostaglandin E-2 in a dose-dependent manner in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages. The inhibitory effect of AF-H on LPS-induced inflammation was also confirmed by down-regulation of inducible NO synthase as well as cyclooxygenase-2 protein expression. Furthermore, treatment with AF-H significantly inhibited secretion of inflammatory cytokines such as tumor-necrosis $factor-{\alpha}$ and interleukin-6. Signal transduction pathway studies further indicated that AF-H inhibited LPS-induced activation of nuclear $factor-{\kappa}B$, but not mitogen-activated protein kinase. Treatment with AF-H also partially protected against LPS-induced lethal shock in C57BL/6 mice, although its effect was not statistically significant. These results suggest that AF-H is a more promising nutraceutical or medicinal agent for inhibition of LPS-induced inflammation or inflammation-related diseases.