288,375 research outputs found
Error-bound formulation for multichannel reception of M-DPSK and pilot-aided M-PSK over Rayleigh-fading channels with postdetection combining
No full textUpper bounds for symbol-error probability are developed for multichannel reception of M-ary phase-shift keying (M-PSK) over frequency-flat Rayleigh-fading channels. Differential coherent demodulation of differentially encoded M-PSK (M-DPSK), pilot-tone aided coherent demodulation of M-PSK (PTA M-CPSK) and pilot-symbol aided coherent demodulation of M-PSK (PSA M-CPSK) are considered in the formulation. The bounds enable the investigation of the effects of fading correlation and unequal average power level between channels using postdetection diversity reception with maximal-ratio combining. Error-performance degradation due to imperfect demodulation effects, such as Doppler spread in M-DPSK schemes, noisy reference signals in PTA M-CPSK, and PSA M-CPSK schemes can be taken into account in the formulation. Exact bit-error probabilities for both binary and quaternary phase-shift keying are also derived.Upper bounds for symbol-error probability are developed for multichannel reception of M-ary phase-shift keying (M-PSK) over frequency-flat Rayleigh-fading channels. Differential coherent demodulation of differentially encoded M-PSK (M-DPSK), pilot-tone aided coherent demodulation of M-PSK (PTA M-CPSK) and pilot-symbol aided coherent demodulation of M-PSK (PSA M-CPSK) are considered in the formulation. The bounds enable the investigation of the effects of fading correlation and unequal average power level between channels using postdetection diversity reception with maximal-ratio combining. Error-performance degradation due to imperfect demodulation effects, such as Doppler spread in M-DPSK schemes, noisy reference signals in PTA M-CPSK, and PSA M-CPSK schemes can be taken into account in the formulation. Exact bit-error probabilities for both binary and quaternary phase-shift keying are also derived
Questions asked and answered in pilot and feasibility randomized controlled trials
No full textAbstract Background In the last decade several authors have reviewed the features of pilot and feasibility studies and advised on the issues that should be addressed within them. We extend this literature by examining published pilot/feasibility trials that incorporate random allocation, examining their stated objectives, results presented and conclusions drawn, and comparing drug and non-drug trials. Methods A search of EMBASE and MEDLINE databases for 2000 to 2009 revealed 3652 papers that met our search criteria. A random sample of 50 was selected for detailed review. Results Most of the papers focused on efficacy: those reporting drug trials additionally addressed safety/toxicity; while those reporting non-drug trials additionally addressed methodological issues. In only 56% (95% confidence intervals 41% to 70%) were methodological issues discussed in substantial depth, 18% (95% confidence interval 9% to 30%) discussed future trials and only 12% (95% confidence interval 5% to 24%) of authors were actually conducting one. Conclusions Despite recent advice on topics that can appropriately be described as pilot or feasibility studies the large majority of recently published papers where authors have described their trial as a pilot or addressing feasibility do not primarily address methodological issues preparatory to planning a subsequent study, and this is particularly so for papers reporting drug trials. Many journals remain willing to accept the pilot/feasibility designation for a trial, possibly as an indication of inconclusive results or lack of adequate sample size.</p
Fast track children's hearing pilot : final report of the evaluation of the pilot
No full textThis report presents key findings of the evaluation of the Fast Track children’s hearings pilot in Scotland. The research was undertaken by staff at the Universities of Glasgow, Stirling and Strathclyde between February 2003 and January 2005
Silver nanoparticle aggregates: Wavelength dependence of their SERS properties in the first transparency window of biological tissues
No full textSemple, John M. interview
No full textOral history interview of Mr. John M. Semple. Interview conducted by Anthony Pilot at 30 Cornell Road, Venice, Florida on December 15, 2018
Pilot-induced oscillation detection and mitigation
No full textThe aim of this thesis is to develop a real time PIO detection and mitigation system that
consists of a detector based on short time Fourier transform(STFT) and autoregressive
model(ARX) with exogenous inputs, together with an adaptive controller based mitigation
system. The system not only detects the traditional PIO characteristics but also focuses on
the trend of pilot behaviour by calculating the rate of change in the open loop crossover
frequency. In the detection system, a sliding windowed STFT method was applied to
identify the frequency and phase characteristics of the system via processing the signal of
pilot input and aircraft state. An ARX model was also applied to get the rate of change
of the crossover frequency. After detection, a PIO cue was shown on the primary flight
display. A scheduled gain controller was coupled to provide PIO mitigation by varying
stick input gain.
Compensatory and tracking tests for the evaluation of this system were performed using
a quasi-linear Boeing-747 aircraft model including nonlinear command gearing and actuator
rate-limiting. Bandwidth and Gibson criteria were used to design PIO prone control
laws for system evaluation experiments. Results from PIO tests conducted on desktop
PCs were presented. These were analyzed and compared with those obtained from implementing
the Real-time Oscillation Verifier module available in literature.Commercial Aircraft
Corporation of China, Ltd (COMAC)and Chinese Scholarship Council
The Importance of Pilot Studies
No full textThe term 'pilot studies' refers to mini versions of a full-scale study (also called 'feasibility' studies), as well as the specific pre-testing of a particular research instrument such as a questionnaire or interview schedule.
Pilot studies are a crucial element of a good study design. Conducting a pilot study does not guarantee success in the main study, but it does increase the likelihood.
Pilot studies fulfil a range of important functions and can provide valuable insights for other researchers. There is a need for more discussion amongst researchers of both the process and outcomes of pilot studies
DESIGN FOR ROBUSTNESS OF A PILOT BUILDING EQUIPPED WITH DISSIPATIVE FREE FROM DAMAGE STEEL CONNECTIONS
No full textRecent research initiative aimed at reducing the structural damage and its inherent economic consequences in steel and steel-concrete composite structures after severe earthquakes led to the development of FREE from DAMage (FREEDAM) beam-to-column connections. The practical applicability and the benefits of using these connections for structures in seismic areas are currently demonstrated within an ongoing RFCS pilot project to be built on the campus of the University of Salerno. Amongst the different structural requirements, Euro-codes nowadays require providing the structures with an appropriate robustness when subjected to identified or unidentified accidental events by ensuring that the undergone damages are not disproportionate to the initiating cause. This paper presents the design for robustness of the pilot building. The results indicate that the loss of a column at the base floor induces the development of significant catenary action in the beams bridging over the lost column. The structural performance under the column loss scenario is primarily governed by the behaviour of beam-to-column joints subsequently identified as critical zones. The full-range behaviour of the FREEDAM joints was investigated through complex numerical simulations which allowed validating a simplified component-based spring model that can be adopted for the regular design of structures adopting this joint typology
Jerome Waller / JB da Pilot oral history interview, 2012
No full textJerome "JB da Pilot" Waller '13 oral history interview conducted by Kevin Kosanovich in Swem Library on 09/19/2012. Virginia Beach native Jerome Waller is also known as JB da Pilot and a member of the Mile High Crew. Topics include: Virginia Beach; Mile High Crew; recording; W&M hip-hop culture; Jay-Z; hip-hop fashion.Jerome Waller, aka J.ust B.ecuz, aka JB da Pilo
The 2012 Pilot Source Study (Phase III): Response to the Pilot Certification and Qualification Requirements for Air Carrier Operations
No full textThe 2012 Pilot Source Study (Phase III) was a continuation of the 2010 Pilot Source Study (Smith, Bjerke, NewMyer, Niemczyk & Hamilton, 2010), using the same research design with a new data set containing no duplicate records. University faculty and students assisted seven regional airlines to enter data on 4,024 pilots hired between 2005 and 2011. New-hire pilots’ college and piloting backgrounds defined their input (Source) variables. Training and first year operations data defined the output (Success) variables. Identifying information for pilots and participating airlines was removed fromthe data sets, and records were combined into a single data set for independent analysis by five researchers. Results were verified by two independent researchers from the University of Central Florida (a non-affiliated university). Results showed considerable consistency between the 2010 Pilot Source Study and the 2012 Pilot Source Study regarding initial pilot training at a regional air carrier. The study found that pilots entering the industry with an aviation-specific college degree, particularly a degree froman AABI-accredited flight program, performed better in initial training than those with no degree or a non-aviation degree. The results also indicated that a pilot’s background, such as having a CFI certificate and obtaining advanced training from a collegiate aviation program, is an indicator of success in training. One important result was that commercial pilots had more completions than pilots with an ATP certificate. On the other hand, total flight hours produced inconclusive results
- …
