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81.
82.
Hounsell N.B. Shrestha B.P. Head J.R. Palmer S. Bowen T. 《Intelligent Transport Systems, IET》2008,2(3):193-200
London has a long history of successful schemes for bus priority at traffic signals. Recently, transport for London (TfL) has procured a modern automatic vehicle location (AVL) system for bus fleet management, passenger information and bus priority. The new system is known as iBUS and is based on Global Positioning System (GPS) and supporting technologies for bus location. The system eliminates the need for on-street hardware for detecting buses and provides more flexibility and opportunity for using bus detectors. However, bus location based on this system is less accurate than location based on fixed infrastructure (e.g. beacons) and could result in reduced benefits from bus priority. This paper first summarises how bus priority at traffic signals works within iBUS, and then explores the effects of GPS locational errors on bus priority benefits. This is followed by a discussion of opportunities available in the context of iBUS to build an even more efficient and beneficial bus priority system by taking advantage of its cost-effective multiple detection capabilities. The paper is based on various studies carried out by the Transportation Research Group (TRG) at the University of Southampton for TfL. 相似文献
83.
People often coordinate their actions with sequences that exhibit temporal variability and unfold at multiple periodicities. We compared oscillator- and timekeeper-based accounts of temporal coordination by examining musicians' coordination of rhythmic musical sequences with a metronome that gradually changed rate at the end of a musical phrase (Experiment 1) or at the beginning of a phrase (Experiment 2). The rhythms contained events that occurred at the same periodic rate as the metronome and at half the period. Rate change consisted of a linear increase or decrease in intervals between metronome onsets. Musicians coordinated their performances better with a metronome that decreased than increased in tempo (as predicted by an oscillator model), at both beginnings and ends of musical phrases. Model performance was tested with an oscillator period or timekeeper interval set to the same period as the metronome (1:1 coordination) or half the metronome period (2:1 coordination). Only the oscillator model was able to predict musicians' coordination at both periods. These findings suggest that coordination is based on internal neural oscillations that entrain to external sequences. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
84.
The influence of a linear loading profile on a slitted bow-tie antenna is discussed. Improvements of the radiation characteristics are achieved by bending the antenna. Simulations and measurements show a S 11 10 dB bandwidth of more than 8:1 and a gain larger than 4.5 dBi. A complete antenna system matched to 50 Ω is proposed 相似文献
85.
Phase Relationships and Physical Properties of Homologous Compounds in the Zinc Oxide-Indium Oxide System 总被引:1,自引:0,他引:1
Toshihiro Moriga Doreen D. Edwards Thomas O. Mason George B. Palmer Kenneth R. Poeppelmeier Jon L. Schindler Carl R. Kannewurf Ichiro Nakabayashi 《Journal of the American Ceramic Society》1998,81(5):1310-1316
Equilibrium phase relationships in the ZnO-In2 O3 system were determined between 1100° and 1400°C using solid-state reaction techniques and X-ray diffractometry. In addition to ZnO and In2 O3 , nine homologous compounds, Zn k In2 O k +3 (where k = 3, 4, 5, 6, 7, 9, 11, 13, and 15), were observed. Electrical conductivity and diffuse reflectance of the k = 3, 4, 5, 7 and 11 members were measured before and after annealing at 400°C for 1 h under forming gas (4%2 -96% N2 ). Room-temperature conductivity increased as k decreased, because of increased carrier concentration as well as increased mobility. In general, transparency in the wavelength range of 450-900 nm increased as k increased. Reduction in forming gas resulted in increased conductivity and reduced transparency for all compounds measured. The highest room-temperature conductivity measured, 270 S/cm, was that of reduced Zn3 In2 O6 . 相似文献
86.
A high-efficiency ground heat exchanger has been developed for use with ground-source heat pumps. The exchanger is made of copper tubing, shaped in the form of a spiral, which can be installed in a vertical borehole backfilled with sand. Thermal performance of a full-scale prototype indicated that this heat exchanger can achieve very high heat extraction rates if subfreezing operating temperatures are used. For most soil types cyclic freezing and thawing is not a problem; however, for the sensitive Leda clay in which the prototype tests were conducted, substantial settlement occurred after the first freeze-thaw cycle owing to initial collapse of the soil structure. 相似文献
87.
Palmer Abraham A.; Miller Mark N.; McKinnon Carrie S.; Phillips Tamara J. 《Canadian Metallurgical Quarterly》2002,116(1):126
Allopregnanolone is a neuroactive steroid that, like ethanol (EtOH), has stimulant, anxiolytic, ataxic, and depressant effects. Two experiments tested the hypothesis that sensitivity to the locomotor stimulant effects of these drugs is influenced by a common set of genes. Sensitivity to the locomotor stimulant effects of allopregnanolone was determined in 24 BXD recombinant inbred (RI) strains. Strain means were positively correlated with extant means for EtOH stimulation in 20 of the same strains. Quantitative trait locus (QTL) analysis provisionally identified many loci, including several known to influence sensitivity to EtOH. Sensitivity to allopregnanolone was also measured in FAST and SLOW mice, which were selectively bred for differential locomotor response to EtOH, to determine whether selection has also altered allopregnanolone sensitivity. FAST mice were more sensitive to the stimulant effects of allopregnanolone compared with SLOW mice. These data suggest that sensitivity to the locomotor stimulant effects of these drugs is influenced by common genes. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
88.
Chloë Palmer 《Network Security》2002,2002(1):8-10
In Part 1 of this Review, we got as far as the middle of the year. The economic climate was driving a lot of discussion and technology usage seemed to take second place to what was economically viable. The major event of this year took place in September, but we still have a little way to go before we get there. And, don’t forget to check out our predictions for 2002 as well. But enough of the doom and gloom, let’s kick off Part II by revisiting some moments the world’s largest software firm would rather forget… 相似文献
89.
A study of more than 9000 unit enrolments in an Australian engineering programme found that: (a) the off-campus withdrawal rate was close to twice that for on-campus students; (b) whether a student withdrew or not was highly correlated to their mode of study; (c) the rate of withdrawal was significantly different between the two student groups; (d) the grade distribution for completing students was significantly different between the two groups; (e) the mean final grade was significantly higher for off-campus students; (f) the failure rate for off-campus students was significantly lower; and (g) the overall wastage rate (withdrawn rate plus fail rate) was significantly higher for off-campus students 相似文献
90.
Stuart R. Palmer 《Canadian Metallurgical Quarterly》2000,126(4):180-185
This paper reports on student responses to a range of assessment activities in a final-year engineering unit. Existing assessment activities were supplemented with new activities, the overall aim being to link the assessment activities more effectively to the material being studied, and to develop a range of generic skills important in professional engineering practice. A class survey was undertaken at the beginning of the semester to establish the initial attitudes to the new assessment activities. This was followed up with an end-of-semester survey to determine the change in perceived value of the assessment activities, and to collect student feedback regarding the activities. The perceived value of the assessment activities was determined using a Likert rating scale, while student feedback was collected using open-ended questions. The assessment activities evaluated were group work, case study investigation, report writing, oral presentation, group self-assessment, industrial interviews, and written reflective journals. The responses indicate that engineering students value a range of assessment activities. They value highly visits to real engineering organizations, and—contrary to popular belief—value and enjoy oral presentation exercises. 相似文献