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ABSTRACTTo study the impact of bus priority control (BPC) on traffic carbon emissions under the strategies of speed guidance, green extension (GE), and red truncation (RT), with consideration of the main influencing factors such as delay, stopping times, and speed, a combination optimization method was used to develop a bi-level optimization model for BPC. The optimal carbon-emission reductions of buses and social vehicles with different fuel types in the upstream section of the intersection and the intersection control area was the upper-level objective, and the optimal total passenger-delay reduction was the lower-level objective. The Gauss – Seidel iterative algorithm was used to solve the model. Finally, the model was applied to the analysis of calculation cases. The results indicated that after BPC was adopted under the guidance acceleration strategy, the reductions in the carbon emissions and total delay of passenger were optimal when the guidance speed was 38 km/h, i.e. 12.67% and 21.05%, respectively. Under the guidance acceleration and GE strategy, the reductions in the carbon emissions and total delay of passenger were optimal when the guidance speed was 39 km/h and the GE was 6 s, i.e. 27.49% and 38.62%, respectively. Under the guidance deceleration and RT strategy, the reductions in the carbon emissions and total delay of passenger were optimal when the guidance speed was 29 km/h and the RT was 6 s, i.e. 22.18% and 33.52%, respectively. The model reduced the carbon emissions and total delay of passenger in the upstream section of the intersection and the intersection control area to achieve the optimal overall traffic benefit for the intersection.

ABSTRACTThis study analyzed the effect of lane-changing behavior on traffic flow emissions and energy consumption of road sections in fuel vehicle-battery electric vehicle (FV-BEV) and human-driven vehicle-cooperative adaptive cruise control (HDV-CACC) multi-dimensional mixed traffic flow environments. Based on the traditional energy consumption model, a multi-dimensional mixed traffic flow energy consumption model was established by considering the BEV and CACC penetration rates. The microscopic traffic flow theory approach was used to analyze lane-changing behavior and the influencing mechanism of lane-changing behavior on the energy consumption of multi-dimensional mixed traffic flow, and MATLAB was used for the experimental simulation. The lane-changing behavior of the leading vehicle had a negative impact on the energy consumption of road segment traffic flow. Within the 95% effective impact range, the average energy consumption of traffic flow with respect to lane-changing behavior was 7.8% higher than that of the following traffic flow. The BEV penetration rate was beneficial for reducing the energy consumption of mixed traffic flow. At an economic velocity, the energy consumption of homogeneous BEV traffic flow was only 58.3% of that of homogeneous FV traffic flow. The CACC penetration rate could increase the traffic flow toughness. When the BEV penetration rate was constant, the higher the CACC penetration rate, the smaller the impact of lane-changing behavior on emissions. When traffic flow was completely transformed to homogeneous CACC traffic flow, lane-changing behavior only increased the overall energy consumption of the traffic flow by 4.99%, which was lower than the average level. Consequently, the promotion of BEV and CACC can improve the impact of traffic emissions on air pollution. When CACC penetration is low, reducing unnecessary lane-changing behavior to ensure the stability of traffic flow is also an effective way to reduce emissions.Implications:Multi-dimensional mixed traffic flow energy consumption model is proposed.CACC penetration rate, BEV penetration rate and lane-changing behavior will change traffic energy consumption. In this paper, different influencing factors are analyzed one by one.It provides a theoretical basis for relevant departments of traffic management to optimize vehicle emissions and traffic organization.

Two novel thermally activated delayed fluorescence (TADF) emitters, 3-phenylquinolino[3,2,1-de]acridine-5,9-dione (3-PhQAD) and 7-phenylquinolino[3,2,1-de]acridine-5,9-dione (7-PhQAD), were designed and synthesized based on a rigid quinolino[3,2,1-de]acridine-5,9-dione (QAD) framework. With the effective superimposed resonance effect from electron-deficient carbonyls and electron-rich nitrogen atom, both emitters realize significant TADF characteristics with small ΔESTs of 0.18 and 0.19 eV, respectively. And, molecular relaxations were dramatically suppressed for both emitters because of their conjugated structure. In the devices, 3-PhQAD realizes superior performance with a maximum external quantum efficiency (EQE) of 19.1% and a narrow full width at half-maximum (FWHM) of 44 nm, whereas a maximum EQE of 18.7% and an extremely narrow FWHM of 34 nm are realized for 7-PhQAD. These superior results reveal that apart from nitrogen and boron-aromatic systems, QAD framework can also act as a TADF matrix with effective resonance effect, and QAD derivatives are ideal candidates to develop TADF emitters with narrow FWHMs for practical applications.

This paper proposes a fast GrowCut (FGC) algorithm and applies the new algorithm in three-dimensional (3D)kidney segmentation from computed tomography (CT) volume data. Users could mark the object of interest with different labels in CT slices.FGC propagates the labels using monotonically decreasing function and color features to derive an optimal cut for a given data in space. The color features play a great role in comparing with neighborhood cells. The experimental results clearly demonstrate the superiority of FGC in accuracy and speed.

Extended high-energy ([?]100 MeV) gamma-ray emission that lasts much longer than the prompt sub-MeV emission has been detected from quite a few gamma-ray bursts (GRBs) by Fermi-Large Area Telescope (LAT) recently. A plausible scenario is that this emission is the afterglow synchrotron emission produced by electrons accelerated in the forward shocks. In this scenario, the electrons that produce synchrotron high-energy emission also undergo inverse Compton (IC) loss and the IC scattering with the synchrotron photons should be in the Klein-Nishina (KN) regime. Here we study effects of the KN scattering on the high-energy synchrotron afterglow emission. We find that at early times the KN suppression effect on those electrons that produce the high-energy emission is usually strong and therefore their IC loss is small with a Compton parameter Y [?] a few for a wide range of parameter space. This leads to a relatively bright synchrotron afterglow at high energies that can be detected by Fermi-LAT. As the KN suppression effect weakens with time, the IC loss increases and could dominate over the synchrotron loss in some parameter spaces. This will lead to a faster temporal decay of the high-energy synchrotron emission than is predicted by the standard synchrotron model, which may explain the observed rapid decay of the early high-energy gamma-ray emission in GRB090510 and GRB090902B.

We revisit the vertical structure of neutrino-dominated accretion flows in spherical coordinates. We stress that the flow should be geometrically thick when advection becomes dominant. In our calculation, the luminosity of neutrino annihilation is enhanced by 1 or 2 orders of magnitude. The empty funnel along the rotation axis can naturally explain the neutrino annihilable ejection.

Metrology plays an important role in the development and commercialisation of micro and nanotechnology. For calibrating versatile micro- and nanoscale standards, a dimensional metrology instrument coupled with multi sensor heads including atomic force microscope (AFM), tactile stylus, laser focus sensor and assembled cantilever probes (ACPs) has been developed. Two kinds of ACPs are highlighted in the paper. One is fabricated by gluing a vertical AFM cantilever to a horizontal AFM cantilever using micro assembling techniques. It is applicable for direct and non-destructive measurements of sidewall surfaces. The other is an ACP ball probe designed for true 3D measurements of micro structures. It is realised by gluing a tungsten wire with a probing sphere ball, 40 ... 120 µm in diameter, to a horizontal AFM cantilever. The ACP ball probe has advantages such as small probing forces (<1µN) and high probing sensitivity. Some typical calibrations on micro and nano structures such as step height, grating and sphere calotte artefact are introduced.

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