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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Realization of Gain and Balance Control for Wearable Double-differential Amplifier

Teng, Hsin-Liang 16 August 2012 (has links)
Low size, low power, and wearable bio-signal recording systems require acquisition front-ends with high common-mode rejection for interference suppression and adjustable gain to provide an optimum signal level to a cascading analog-to-digital stage. This thesis presents the realization of microcontroller operated double-differential (DD) recording setup with automatic gain control (AGC) and automatic balance control, which can adjust the magnitude of recorded bio-potential signal to a target level and reject common-mode interference for full-bandwidth recording without filtering. Microcontroller code realizes the automatic control method of gain and balance adjustment by detecting, computing, and varying parameters to set timing clock pulses, which determine the gain magnitude and balance state. The automatic balance control compensates for imbalance in electrode interface impedance. The double-differential amplifier is implemented using two integrated variable gain amplifiers (ASIC) and one adder. Measured results of the variable gain amplifiers fabricated in 0.35 £gm CMOS technology show an input spot noise of 169 nV/¡ÔHz, a NEF below 10, and a circuit active area of 0.017 mm2 with a power consumption of 1.44 £gW. Measured results of the double-differential amplifier setup confirm interference suppression of 25.7 dB, tunable gain range of 39.6 dB, and 239 nV/¡ÔHz noise assuming ¡Ó10% interface mismatch. Practical measured examples incorporating the chips confirm gain control suitable for bio-potential recording and interference suppression in a balanced DD arrangement for electrocardiogram and electromyogram recording.
12

Molecular Mechanism of AGC Kinases in Human Malignant

Shu, Shaokun 15 October 2010 (has links)
The maintenance of normal cell function and tissue homeostasis is dependent on the precise regulation of multiple signaling pathways that control cellular decisions to either proliferate, differentiate, arrest cell growth, or initiate programmed cell death (apoptosis). Cancer arises when clones of mutated cells escape this balance and proliferate inappropriately without compensatory apoptosis. Deregulated cell growth occurs as a result of perturbed signal transduction that modulates or alters cellular behavior or function to keep the critical balance between the rate of cell-cycle progression (cell division) and cell growth (cell mass) on one hand, and programmed cell death (apoptosis, autophagy) on the other. AGC kinases are activated downstream of a wide range of extracellular stimuli by distinct mechanisms. AGC kinase members such as Aurora-A and Akt regulate fundamental cellular functions including cell cycle, cell growth and survival. Inappropriate activation of those kinases has been associated with the development of diseases such as diabetes, autoimmunity, and cancer. The molecular mechanism of AGC kinases including Aurora-A and Akt involved in human cancers indicates that Aurora-A and Akt are important targets for cancer therapeutic strategies. We demonstrate, for the first time, that Aurora-A interacts with AR and phosphorylates AR at Thr282 and Ser293 in vitro and in vivo. Aurora-A induces AR transactivation activity in a phosphorylation-dependent manner. Ectopic expression Aurora-A in LNCaP cells induces the PSA expression and cell survival whereas knockdown of Aurora-A sensitizes LNCaP-RF cells to apoptosis and cell growth arrest. These data indicate that AR is a substrate of Aurora-A and that elevated Aurora-A could contribute to androgen-independent cell growth by phosphorylation and activation of AR. The NACHT leucine-rich repeat protein 1 (NALP1) is a member of the Ced-4 family and locates at chromosome 17p13.2 near TP53 locus. Here we demonstrated frequent somatic mutations and epigenetic silence of the NALP1 in human non-small cell lung, breast, ovarian and colon cancer. Restoration of NALP1 resulted in the inhibition of tumorigenic activity of the cell lines with NALP1 alterations. In addition to apoptosis, the cells expressing NALP1 largely undergo autophagy. Expression of NALP1 induces PI3KC3 kinase activity through directly interacts with Beclin 1, a protein required for activation of PI3KC3. Moreover, Akt phosphorylates NALP1 and disrupts the interaction between NALP1 and Beclin 1, leading to abrogation of NALP1-induced PI3KC3 activation and autophagy. Taken collectively, these data indicate that the NALP1 is a novel tumor suppressor gene on chromosome 17p13 and plays an important role in tumorigenesis by regulation of Beclin 1/PI3KC3 autophagic pathway and that Akt inhibits autophagy through regulation of NALP1/Beclin/ PI3KC3 cascade.
13

Garso signalo automatinis amplitudės reguliavimas / Automatic adjustment of audio signal amplitude

Laurutis, Žygimantas 28 September 2012 (has links)
Šis darbas yra apie įrenginį, kuris siaurina garsinio signalo dinaminį diapazoną. Darbe lyginami automatinio stiprinimo reguliavimo metodai, bei jų taikymai pramoniniuose garso kompresoriuose. Ieškoma būdų šiuos įrenginius patobulinti. / This article is about apparatus that intentionally reduces the dynamic range of audio signals. The goal is to compare methods of automatic gain reduction, talk their implementation in industry standard hardware compressors and look for possible circuit modifications.
14

Activity and Regulation of AGC Kinases from Physcomitrella patens and Tomato

Nelson, Anna 2012 August 1900 (has links)
The AGC group of protein kinases (named for protein kinases A, G, and C) is found in all eukaryotes studied so far, and its members coordinate essential cellular processes including translation, metabolism, hormone response, growth, and survival. AGC kinases are intensively studied in mammals because of their connection with human diseases like cancer, diabetes, and neurological disorders. Some aspects of AGC kinase function are organism-specific, but others are conserved in highly divergent species. Several AGC kinases are regulated by the conserved 3-phosphoinositide dependent protein kinase-1 (PDK1), which is itself an AGC kinase. PDK1 regulates its substrates through phosphorylation at a conserved site in their activation loop. Here, I identify and characterize a PDK1 homologue from the moss Physcomitrella patens (PpPDK1). I show PpPDK1 phosphorylates plant AGC kinases in the activation loop, but unexpectedly lacks a lipid-binding domain, suggesting that its regulation differs from other species. In contrast to mammalian cells, PpPDK1 is not an essential gene, suggesting that AGC kinase pathways in P. patens are sufficient for survival even in the absence of activation by PpPDK1. I analyze putative PDK1 sequences from 100 different eukaryotic species, finding that many PDK1s differ from the "conventional" PDK1 found in humans. Phylogenetic analysis of these sequences suggests a complicated evolutionary history for PDK1, with the potential for unexpected functional and regulatory features. I also investigate the regulation of Adi3, an AGC kinase from tomato, through phosphorylation by PDK1. I identify a novel putative PDK1 phosphorylation site outside the kinase domain, which appears to increase Adi3 activity on a substrate. Finally, I produce a mutant version of Adi3 that can selectively utilize bulky ATP analogues. This analogue-sensitive protein may be used in a future search for direct Adi3 substrates. Together, my experiments provide insight into two members of the AGC group of protein kinases, one (PDK1) that is conserved in all eukaryotes and one (Adi3) that appears to be present only in plants. These experiments give a new perspective in our view of plant AGC kinase function and regulation.
15

Regulación Secundaria de Frecuencia Mediante un Sistema AGC

Hott Riquelme, Alfredo Armando January 2007 (has links)
No description available.
16

ULTRA LOW POWER READ-OUT INTEGRATED CIRCUIT DESIGN

Chen, Jian 27 August 2012 (has links)
No description available.
17

Wideband Automatic Gain Control Design in 130 nm CMOS Process for Wireless Receiver Applications

Strzelecki, Joseph Benito 28 August 2015 (has links)
No description available.
18

The Study of Externally Modulated AM Video Lightwave Transmitter

Lin, Hsien-Sheng 27 June 2000 (has links)
Abstract In this thesis, we use a high power 1550 nm DFB laser and a Ti:LiNbO3 Mach-Zehnder modulator to construct an externally modulated trensmitter for CATV lightwave system. We use two methods to reduce the problem caused by stimulated Brillouin scattering (SBS) effect in externally modulated AM video system by using high-frequency phase modulation and low-frequency dithering techniques. In this experiment, the SBS threshold can be increased by 6 dB. We also design a automatic gain control (AGC) circuit with a 10 dB dynamic range in our transmitter. After addition with a home-made predistortion linearized circuit, the system performance of this transmitter in a 20 km single-mode fiber link carrying 60 NTSC channels can be achieved with a CNR¡Ù46~52 dB¡BCSO¡Ø-68~-73 dBc¡BCTB¡Ø-59~-63 dBc. As the number of channels increased from 60 to 80, we can obtain CNR¡Ù46~51 dB, CSO¡Ø-65.5~-71 dBc, and CTB¡Ø-55~-60.4 dBc. According to preceding description, we know that our trensmitter can carry 60 ~ 80 NTSC channels.
19

A methodology to enable wind farm automatic generation control

Han, Hai-Yue 03 January 2012 (has links)
Over the last decade the increase in penetration of wind power and its variable nature has begun to add considerable stress to and threatened the stability of the nation's grid. In order to continue growth wind farms will need to have the ability to participate in the same grid frequency regulation as traditional generating sources. The goal of this research is to explore the use of energy storage devices to provide wind farms with a method to regulate their power output and the grid frequency. Using energy storage, this research aims to allow wind farms to participate in automatic generation control (AGC). Software simulations were performed to design an advanced energy storage controller that will allow maximum participation in AGC. A comprehensive in-lab grid was constructed to produce experimental results for this work and was used to evaluate the performance of the advanced energy storage controller. The first stage of this research aims to use super-capacitors to balance rapid excursions in frequency and wind power output while the second stage of this research will preliminarily explore the use of a zinc-bromine flow cell battery for medium-scale, sustained excursions in frequency and wind power output. Results show that wind farms are capable of participation in AGC with the addition of an energy storage device, but the amount of participation is heavily reliant on the amount of energy storage available. / Graduation date: 2012
20

Determining the Value of a Master's Degree in Construction Management

Davis, Benjamin K. 21 July 2006 (has links) (PDF)
The purpose of this study is to determine the value of a master's degree in construction management in southern Idaho. A telephone and Internet survey was employed to determine the value that members of the construction industry in southern Idaho place on construction management (CM) degrees, both graduate and undergraduate. The survey included 27 self-described general contractors who are members of The Associated General Contractors of America (AGC) in regions 3 and 4 in the state of Idaho. Regions three and four include Twin Falls, Idaho Falls, Pocatello, Ketchum, Burley and surrounding communities. Following the compilation of surveys, it was found that the group of participants 1) knew there was a bachelor's degree in CM; however, some didn't realize there was a master's degree in CM; 2) felt that education is sometimes over rated; 3) perceived no difference in hiring an undergraduate v. a graduate in terms of monetary value. There was a perceived value in a master's degree itself.

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