• 제목/요약/키워드: Signal Factor

검색결과 1,853건 처리시간 0.027초

Tumor Necrosis Factor Receptor (TNFR)-associated factor 2 (TRAF2) is not Involved in GM-CSF mRNA Induction and TNF-Mediated Cytotoxicity

  • Kim, Jung-Hyun;Cha, Myung-Hoon;Lee, Tae-Kon;Seung, Hyo-Jun;Park, Choon-Sik;Chung, Il-Yup
    • Journal of Microbiology
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    • 제37권2호
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    • pp.111-116
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    • 1999
  • Tumor necrosis factor receptor (TNFR)-associated factor 2 (TRAF2) is known to act as a signal transducer that connects TNFR2 to its downstream effector functions such as proliferation of thymocytes, regulation of gene expression, and cell death. TRAF2 consists of largely two domains, the N-terminal half that contains a signal-emanating region and the C-terminal half that is responsible for binding to the intracellular region of TNFR2. In this study, we examined the possible roles of TRAF2 in granulocyte-macrophage colony-stimulating factor (GM-CSF) gene expression and cell death. A truncated mutant of TRAF2 ( 2-263) that contains only a C-terminal half was generated, and transiently transfected to the A549 cell, a human lung cancer cell line, and L929 cell, a murine TNF-sensitive cell line. GM-CSF mRNA was induced in untransfected A540 cells both in dose- and time-dependent manner upon the exposure of TNF. However, neither the full length TRAF2 nor the mutant altered GM-CSF mRNA production regardless of the presence or absence of TNF. Furthermore, neither TRAF2 versions significantly changed the cytotoxic effect of TNF on L929 cells. These data suggest that TRAF2 may not be involved in the signal transduction pathway for GM-CSF gene induction and cell death mediated by TNF.

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General Linearly Constrained Broadband Adaptive Arrays in the Eigenvector Space

  • Chang, Byong Kun
    • Journal of information and communication convergence engineering
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    • 제15권2호
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    • pp.73-78
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    • 2017
  • A general linearly constrained broadband adaptive array is examined in the eigenvector space with respect to the optimal weight vector and the adaptive algorithm. The optimal weight vector and the general adaptive algorithm in the eigenvector space are obtained by eigenvector matrix transformation. Their operations are shown to be the same as in the standard coordinate system except for the relevant transformed vectors and matrices. The nulling performance of the general linearly constrained broadband adaptive array depends on the gain factor such that the constraint plane is shifted perpendicularly to the origin by an increase in the gain factor. The general linearly constrained broadband adaptive array is observed to perform better than a conventional linearly constrained adaptive array in a coherent signal environment, while the former performs similarly to the latter in a non-coherent signal environment.

Analysis, Design, and Implementation of a Single-Phase Power-Factor Corrected AC-DC Zeta Converter with High Frequency Isolation

  • Singh, Bhim;Agrawal, Mahima;Dwivedi, Sanjeet
    • Journal of Electrical Engineering and Technology
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    • 제3권2호
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    • pp.243-253
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    • 2008
  • This paper deals with the analysis, design, and implementation of a single phase AC-DC Zeta converter with high frequency transformer isolation and power factor correction(PFC) in two modes of operation, discontinuous current mode of operation(DCM), and continuous current mode of operation(CCM). A Digital Signal Processor(DSP) based implementation is carried out for validation of the Zeta converter developed design in discontinuous mode of operation. A comparison of both modes of operation is presented for a 1kW power rating from the point of view of steady state and dynamic behavior, power quality, simplicity, control technique, device rating, and converter size. The experimental results of a developed prototype of Zeta converter are presented for validation of the developed design. It is observed that CCM is most suitable for higher power applications where it requires some complex control and sensing of the additional variables.

A Simple Grid-Voltage-Sensorless Control Scheme for PFC Boost Converters

  • Nguyen, Cong-Long;Lee, Hong-Hee;Chun, Tae-Won
    • Journal of Power Electronics
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    • 제14권4호
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    • pp.712-721
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    • 2014
  • This paper introduces a simple grid-voltage-sensorless control scheme for single-phase power factor correction (PFC) boost converters. The grid voltage waveform is obtained based on the dc output voltage, the switching duty ratio, and a phase-lead compensator. In addition, the duty ratio feedback is utilized to obtain the unity input power factor and the zero harmonic current. The proposed control scheme is designed and mathematically analyzed based on a small-signal model of PFC boost converters. To verify the effectiveness of the proposed control scheme, several simulations and experiments are carried out in two applications: an industrial power system with a 60 Hz grid frequency and a commercial aircraft application with a 400 Hz grid frequency.

AE신호에 의한 칩 절단성 예측 (Chip Breaking Prediction Using AE Signal)

  • 최원식
    • 한국생산제조학회지
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    • 제8권4호
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    • pp.61-67
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    • 1999
  • In turning the chip may be produced in the form of continuous chip or discontinuous one. Continuous chips produced at high speed machining may hit the newly cut workpiece surface and adversely affect the appearance of the surface finish and may interfere with tool and sometimes induce tool fracture. In this study relationship between AE signal and chip form was experimentally investigated, The experimental results show that types of chip form are possible to be classified from the AE signal using fuzzy logic.

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원통연삭시 휠속도 변화의 패턴인식을 이용한 채터감시에 관한 연구 (A Study on the Monitoring of Chatter Vibration Using Pattern Recognition in the Plunge Grinding)

  • 이종열;송지복;곽재섭
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 1995년도 추계학술대회 논문집
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    • pp.28-32
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    • 1995
  • Bacause the chatter vibration is a main factor to damage on the quality and integrity, The cure is required peticurity in cykinderical plunge grinding. The chatter vibration relatied with wheel speed, workpiece and infeed rate. Therefore, we expressed more credible normal signal and chatter signal Pattern in accrdiance with wheel speed and acquired RMS signal of the accelerrometer. In thos study, after finding the chatter pattern, we applied two parameters, standard deviation and Kurtosis, to Neural Network.

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Slotted Line의 Signal Flow Graph 해석 (Analysis on Signal Flow Graph of Slotted LIne)

  • 박기수
    • 대한전자공학회논문지
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    • 제6권3호
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    • pp.8-11
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    • 1969
  • In the precision measurement of the voltage standing wave ratio (VSWR) or reflection coefficient by means of the slotted line technique, one of the important factors is the maximum error due to the discontinuities and multi-reflection in the slotted line. Particularly, this error becomes a critical factor when the VSWR or the reflection coefficient to be measured is very small. In this paper, the exact expression of this error is obtained by means of the Signal flow graph method.

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생체신호 데이터의 압축코드 알고리즘에 관한 연구 (A Study on the Compressed Code for Biological Signal)

  • 홍승홍;손창일;민홍기
    • 대한의용생체공학회:의공학회지
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    • 제5권1호
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    • pp.93-102
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    • 1984
  • In this paper, the real-time compressed code generation method for the biological signal data, especially for the Electrocardiogram, is studied. For this purpose, variable length code is introduced. And from this code, we get a exactly the same reconstructed signal data as the original. Experimental results show that this program reduces the data rate by a factor of about 8, and codes the result in a form convenient for analysis.

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Interference of Fisetin with Targets of the Nuclear Factor-κB Signal Transduction Pathway Activated by Epstein-Barr Virus Encoded Latent Membrane Protein 1

  • Li, Rong;Liang, Hong-Ying;Li, Ming-Yong;Lin, Chun-Yan;Shi, Meng-Jie;Zhang, Xiu-Juan
    • Asian Pacific Journal of Cancer Prevention
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    • 제15권22호
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    • pp.9835-9839
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    • 2014
  • Fisetin is an effective compound extracted from lacquer which has been used in the treatment of various diseases. Preliminary data indicate that it also exerts specific anti-cancer effects. However, the manner in which fisetin regulates cancer growth remains unknown. In this study, we elucidated interference of fisetin with targets of the nuclear factor ${\kappa}B$ signal transduction pathway activated by Epstein-Barr virus encoding latent membrane protein 1 (LMP1)in nasopharyngeal carcinoma (NPC) cells, Results showed that fisetin inhibited the survival rate of CNE-LMP1 cells and NF-${\kappa}B$ activation caused by LMP1. Fisetin also suppressed nuclear translocation of NF-${\kappa}B$ (p65) and $I{\kappa}B{\alpha}$ phosphorylation, while inhibiting CyclinD1, all key targets of the NF-${\kappa}B$ signal transduction pathway. It was suggested that interference effects of fisetin with signal transduction activated by LMP1 encoded by the Epstein-Barr virus may play an important role in its anticancer potential.

직진교통의 좌회전차선 이용률 추정과 교차로용량 및 최적신호등시간 산정 (Estimating Utilization Factor of Left Turn Lane for Through Traffic, Intersection Capacity, and Optimum Signal Timings)

  • 도철웅
    • 대한교통학회지
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    • 제1권1호
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    • pp.56-63
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    • 1983
  • Intersection control has dual-purposes; increasing capacity and reducing delay. The primary concern of efficient intersection control under oversaturated condition as in Korea is to increase capacity. Prevailing intersection operation technique permits thru traffic to utilize left turn lane, because the intersection without left turn pocket has left turn signal interval. In this situation, it seems not to be valid to calculate capacity, delay, and signal timings by conventional methods. By critical lane technique, capacity increases as cycle length increases. However, when thru traffic utilize LT lane, the capacity varies according to LT volume, LT interval as well as cycle length, which implies that specific cycle length and LT interval exist to maximize capacity for given LT volume. The study is designed is designed to calculate utilization factors of LT lane for thru traffic and capacities, and identify signal timings to yield maximum capacity. The experimental design involved has 3 variables; 1)LT volumes at each approach(20-300 vph), 2)cycle lengths (60-220 sec), and 3)LT intervals(2.6-42 sec) for one scenario of isolated intersection crossing two 6-lanes streets. For LT volume of 50-150 vph, capacity calculated by using the utilization factor is about 25% higher than that by critical lane method. The range of optimum cycle length to yield maximum capapcity for LT volume less than 120 vph is 140-180 sec, and increases as LT volume increases. The optimum LT interval to yield maximum capacity is longer than the intrval necessary to accommodate LT volume at saturation flow rate.

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