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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.
161

Wireless Near-ground Channel Characteristics in Several Unlicensed Bands

Zhang, Qian 03 October 2008 (has links)
No description available.
162

The cellular chloride channels CLIC1 and CLIC4 contribute to virus-mediated cell motility

Stakaityte, G., Nwogu, N., Lippiat, J.D., Blair, G.E., Poterlowicz, Krzysztof, Boyne, James R., Macdonald, A., Mankouri, J., Whitehouse, A. 02 August 2018 (has links)
Yes / Ion channels regulate many aspects of cell physiology, including cell proliferation, motility, and migration, and aberrant expression and activity of ion channels is associated with various stages of tumor development, with K+ and Cl- channels now being considered the most active during tumorigenesis. Accordingly, emerging in vitro and preclinical studies have revealed that pharmacological manipulation of ion channel activity offers protection against several cancers. Merkel cell polyomavirus (MCPyV) is a major cause of Merkel cell carcinoma (MCC), primarily due to the expression of two early regulatory proteins termed small and large tumour antigens (ST and LT, respectively). Several molecular mechanisms have been attributed to MCPyVmediated cancer formation but thus far, no studies have investigated any potential link to cellular ion channels. Here we demonstrate that Cl- channel modulation can reduce MCPyV STinduced cell motility and invasiveness. Proteomic analysis revealed that MCPyV ST upregulates two Cl- channels; CLIC1 and CLIC4, which when silenced, inhibit MCPyV STinduced motility and invasiveness, implicating their function as critical to MCPyV-induced metastatic processes. Consistent with these data, we confirmed that CLIC1 and CLIC4 are upregulated in primary MCPyV-positive MCC patient samples. We therefore, for the first time, implicate cellular ion channels as a key host cell factor contributing to virus-mediated cellular transformation. Given the intense interest in ion channel modulating drugs for human disease, this highlights CLIC1 and CLIC4 activity as potential targets for MCPyV-induced MCC. / BBSRC DTP studentship (BB/J014443/1) and Royal Society University Research Fellowship to JM (UF100419)
163

A Method for the Determination of Design Discharges for Urban Stream Restoration Projects in Northern Virginia

Petrey, Scott Raymond 24 May 2011 (has links)
It is well documented that urbanization changes the hydrology of watersheds (Hammer 1972; Booth 1991; Rose and Peters 2001). Increases in runoff volume and velocity from urbanization result in stream channel degradation (Hammer 1972; Henshaw and Booth 2000; Walsh et al. 2005; Leopold et al. 2005a; Poff et al. 2006). While stormwater management measures may be implemented to reduce the impact of stormwater runoff on streams, these practices do not reverse stream channel degradation that has already occurred. Stream restoration utilizing Natural Channel Stream Design (NCD) techniques is an effective way to reverse the effects of urbanization and return natural function to a stream. The design (bankfull) discharge for an NCD stream restoration project is the cornerstone of a restoration design. Existing methodologies for determining design discharges, such as hydrologic modeling and bankfull identification, have not worked well for NCD stream restoration projects in urban watersheds. The use of hydraulic geometry relationships serves as an alternative method for determining design discharge, but the required information is not generally available for urban Northern Virginia streams. However, rural regional curves developed for the Maryland piedmont, adjusted for watershed impervious area, provide a means to determine design discharges for urban stream restoration projects in Northern Virginia. / Master of Science
164

Aeronautical Channel Simulation in Network Simulators for Incorporation into OPNET

Zhang, Tianyin, Jaber, Nur 10 1900 (has links)
ITC/USA 2010 Conference Proceedings / The Forty-Sixth Annual International Telemetering Conference and Technical Exhibition / October 25-28, 2010 / Town and Country Resort & Convention Center, San Diego, California / This paper discusses channel simulation using OPNET Modeler in support of iNET. It shows how wireless communication is simulated, how to simulate the special aeronautical channel of iNET, and how to deliver the aeronautical channel, test article, and ground station as reusable components for future simulation. Network simulation is a critical tool for iNET and it enables design decisions that cannot be made analytically due to the complexity of the problem. This work addresses the incorporation of the aeronautical channel into the OPNET Modeler tool set as this piece of iNET is unique and is not available in OPNET Modeler.
165

Estimating the Characteristics of the Aeronautical Telemetry Channel during Bit Error Events

Law, Eugene L. 10 1900 (has links)
International Telemetering Conference Proceedings / October 25-28, 1999 / Riviera Hotel and Convention Center, Las Vegas, Nevada / This paper presents estimated aeronautical telemetry channel characteristics during bit error events. A T-39 aircraft was flown around various test corridors while transmitting a filtered 10 Mb/s pseudo-noise (PN) sequence binary phase shift keying (BPSK) signal. The received signal was down converted to 70 MHz, digitized when trigger criteria were met, and stored for later analysis. Received signal strength was also recorded. The first step in data analysis consisted of dividing the fast Fourier transform (FFT) of the recorded signal by the FFT of the expected signal. The received signal strength data was then used to correct for flat fade effects. The resulting signal is the difference (dB) between the expected signal at the receiver intermediate frequency (IF) output and the measured receiver IF output during the error event. This difference is the aeronautical telemetry channel characteristic. The characteristics of this difference signal were then matched against a 2-ray and 3-ray multipath fading model with reflected signal amplitude and path delay as the variables.
166

FLIGHT TEST MONITORING OF AVIONIC FIBRE CHANNEL NETWORKS FOR RECORDING AND TELEMETRY

Zettwoch, Robert N. 10 1900 (has links)
International Telemetering Conference Proceedings / October 20-23, 2003 / Riviera Hotel and Convention Center, Las Vegas, Nevada / The F/A-18E/F Super Hornet fighter aircraft program is currently flight testing a Fibre Channel Network (FCN), which will initially replace certain Avionics Systems’ MIL-STD-1553 communications. The Advanced Mission Computers and Displays (AMC&D) and the Active Electronically Scanned Array (AESA) RADAR are replacing their MIL-STD-1553 counterparts to fulfill performance enhancements and growing data requirements. The maximum amount of data that can be transferred between these systems is significantly increasing. Each remote terminal on a MIL-STD-1553 bus can transmit or receive approximately 1Mbps. Each node on a FCN can simultaneously transmit and receive 1Gbps. With a Fibre Channel Network Switch (FCNS), multiple systems can communicate concurrently, thus increasing overall system throughput even further. Several other systems will be replaced in the near future utilizing the FCNS. The Fibre Channel Interface Unit (FCIU) was designed for the F/A-18E/F AESA program as a nonintrusive way to monitor multiple nodes, extract node specific information, and record this information using conventional on-board recorders. In order to reduce the risks associated with developing hardware and software concurrently with the Avionic System’s protocol, the FCIU was developed as an upper-level-protocol (ULP) (layer FC-4) independent device. Two big advantages of ULP independence are the avoidance of complex protocol programming for each different type of monitored network system and the non-intrusive nature of the FCIU connection to the FCN. This facilitates the quick installation of the FCIU to monitor any FC network and the FCIU IRIG-106 PCM type output lends itself to be integrated quickly into a typical Flight Test data recording or telemetry system.
167

An investigation into the physical modelling of a doubly meandering two stage channel and the development of a design procedure

Naish, Colin January 1996 (has links)
No description available.
168

Performance analysis of bandwidth-efficient modulation schemes for high capacity wireless networks 1

Chow, Y. C. January 1997 (has links)
No description available.
169

Dispersion of a heavy plume in a structured shear layer

Cheah, S. C. January 1984 (has links)
No description available.
170

Genetic algorithm assisted CDMA multiuser detection

Yan, Kai January 2001 (has links)
No description available.

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