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HSR studies have been one of the most important issues in economic geography, transport economics and policy. However, prior studies give rare attention to its role on the technological innovation collaboration, which become increasing important nowadays. Using co-patent data of the State Intellectual Property Office (SIPO) database from 2000 to 2016, this paper investigates the role of HSR services in cross-city technological innovation collaboration. Empirical results show: 1) the intensity of cross-city technological innovation collaboration activities remains at a low level before the debut of HSR services in China, and the difference on this indicator between cities with and without HSR services is statistically insignificant. With the emergence of HSR network, cross-city innovation collaboration is booming and cities with and without HSR services show distinct trends. 2) HSR services play a significant positive role in stimulating the intensity of cross-city technological innovation collaboration activities of HSR cities. 3) megacities benefit most from the HSR network, and secondary cities also benefit from being connected to megacities by HSR lines. 4) The travel time between city pairs is significantly correlated with the intensity of collaborative innovation activities. Our results suggesting interregional innovation bonds, which implicitly featuring the channel of knowledge flow, are established or strengthened by high-speed transport investments. • We find that HSR services play a significant positive role in stimulating the intensity of cross-city technological innovation collaboration activities of HSR cities. • Megacities benefit most from the HSR network, and secondary cities also benefit from being connected to megacities by HSR lines. • The travel time between city pairs is significantly correlated with the intensity of collaborative innovation activities. [ABSTRACT FROM AUTHOR]

In the hoisting system of mine and elevator, the wire rope will generate rotational motion with unfixed axis, the rotation angle of which is a vital parameter for the system. Therefore, it is necessary to measure the rotation angle to evaluate the torsional state of the rope. This paper proposes an unfixed-axis wire rope rotation angle measurement method, which mainly includes two parts, the axis positioning of the rope and the rotation tracking process. Firstly, the axis positioning method of the rope is introduced. Then, the geometrical principle of rope rotation measurement and the framework of Lucas–Kanade tracking algorithm are explained. Finally, a simulation test and a rotation experiment verify the performance of the proposed algorithm, and the influence of axis positioning error and radius recognition error on the measurement are discussed. The proposed method provides an effective way for the measurement of wire rope. [Display omitted] • Target-less method for measuring the rotation of rope with unfixed axis is proposed. • Axis positioning of wire rope based on iterative solving is presented. • Geometric relationship of image coordinates during rotation is illustrated. • Factors affecting rotational measurement are analyzed. [ABSTRACT FROM AUTHOR]

Determining if there is any coal left in the coal mine skip unloading is a challenging problem. We propose a new object tracking method to provide new ideas to solve the problem of whether there is residual coal in the skip unloading. In this study, a fast vision-based measurement framework about new diamond search normalized cross-correlation (NDS-NCC), including a movement prediction part and a template tracking part, is used. Firstly, a diamond search method with fast adaptive coarse localization is proposed to overcome the time-consuming problem of NCC template matching process. Secondly, we incorporate a template updating strategies that allows targets to be tracked consistently. The performance of the NDS-NCC algorithm was tested on the bench and at the coal mine site for balancing cylinders and wire rope tracking. The results show that the NDS-NCC algorithm has better efficiency (7 ms/frame) and accuracy (0.4512 px) in the coal mine field application. [Display omitted] • A fast template matching method without identifiers is proposed. • An adaptive Kalman motion estimation method is proposed based on the actual working conditions. • A new template update mechanism is proposed. • The algorithm was verified by experimentally tracking different objects. [ABSTRACT FROM AUTHOR]

• GABP can effectively address the forward kinematics problems of Delta robot. • If the tolerance prediction error of ±0.05 mm is acceptable to the high precision control of Delta parallel robot system, mobile platform endpoint of the Delta robot system can achieve 97.75% accurate positing according to the Predicted Coordinate Pairs. • The proposed model overcomes weakness of traditional forward kinematics methods. Aiming at solving the problems of complex forward kinematics of Delta parallel robot and multiple solutions, and further improving celerity and accuracy of positioning for the spatial pose of the manipulator end effecter, in this paper, we present a method to kinematics solution of Delta parallel robot based on BP neural network. Taking the three-degree-of-freedom Delta parallel robot as the research object, according to analysis of its the kinematics principle, the basic BP neural network model and the optimized BP neural network model for kinematics solution of Delta parallel robot are simulated by using MATLAB, respectively. The results indicate that using BP neural network model improved by Genetic Algorithms to address the forward kinematics problems of Delta parallel robot is feasible, which can achieve the requirement of higher celerity and accuracy of Delta parallel robot control and avoid the shortcomings of traditional methods to a certain extent, furthermore, ensures the reliability of production safety. [ABSTRACT FROM AUTHOR]

The hoisting rope has complex dynamic characteristics under external excitation during operation, characterized by large longitudinal movement and minor lateral oscillation. However, there are no appropriate approaches to acquire the dynamic displacement of the rope currently. In this study, a fast vision-based measurement framework, including initial value forecast (IVF) and target tracking based on Lucas–Kanade (LK) algorithm, called IVF-LK, is proposed to obtain the lateral-longitudinal displacement of the rope. Firstly, an IVF method is proposed to obtain the initial value of iteration, overcoming the problem of non-convergence of LK algorithm under large displacement. Secondly, a parameter update strategy makes the convergence speed of LK significantly improved. Then, the performance of IVF-LK algorithm was tested in the experimental bench, which reveal its superior capacity in rope-structure dynamic measurement both in efficiency and precision. Finally, a field experiment was implemented to analyze the dynamic displacement of the hoisting rope. • Vision-based measurement framework of hoisting rope is proposed. • Non-convergence problem of Lucas–Kanade algorithm under large movement is addressed. • The update strategy improves the convergence speed of the Lucas–Kanade algorithm. • Asynchronous movement of multiple hoisting ropes will occur in the hoisting system. [ABSTRACT FROM AUTHOR]

In this paper, a modelling method and an accurate numerical procedure are presented to simulate the dynamical responses of a multi-cable driven parallel suspension platform system. For such systems, the cables might become slack due to external excitations and due to the fact that cables can become tensionless when been pushed in longitudinal direction. In lateral and torsional directions, the constraint forces between the cables and platform can be positive as well as negative. This paper will deal with the non-smooth cable vibrations (in longitudinal, lateral and torsional directions) by taking into account the slackness of the cables. Firstly, the Lagrange equation with constraints is used to derive the equations of motion of the multi-cable suspension platform. Then, by expressing the equations of motion and constraint equations at velocity level, a non-smooth algorithm is used to numerically solve the equations. Finally, the numerical results are compared with an ADAMS simulation, and the two results agree well with each other. Moreover, the results in this paper significantly improve the numerical results used in the analysis of the dynamics for multi-cable systems which usually neglect the lateral properties of the cables. [ABSTRACT FROM AUTHOR]

Accurate monthly electricity consumption forecasting can provide the reliable guidance for better energy planning and administration. However, it has been found that the monthly electricity consumption demonstrates a complex nonlinear characteristic and an obvious seasonal tendency. Support vector regression has been widely applied to handle nonlinear time series prediction, but it suffers from the key parameters selection and the influence of seasonal tendency. This paper proposes a novel approach, which hybridizes support vector regression model with fruit fly optimization algorithm and the seasonal index adjustment to forecast monthly electricity consumption. Besides, in order to comprehensively evaluate the forecasting performance of the hybrid model, a small sample of monthly electricity consumption of China and a large sample of monthly electricity retail sales of the United States were employed to demonstrate the forecasting performance. The results show that the proposed hybrid approach is a viable option for the electricity consumption forecasting applications. [ABSTRACT FROM AUTHOR]

Abstract: A stable organic solar cell with structure of ITO/buffer/donor/acceptor/cathode is presented. A thin layer (5nm) of MoO3-doped CuPc is adopted as the buffer in CuPc/C60 organic heterojunction photovoltaic (PV) solar cells, resulting in two times longer lifetime. The surface morphology of buffer layer plays a decisive role in improving the stability. [Copyright &y& Elsevier]

Rationale and Objectives: Challenges remain in the imaging of the lungs of free-breathing mice. Although computed tomographic (CT) imaging is near optimal from a contrast perspective, the rapid respiration rate, limited temporal resolution, and inflexible x-ray pulse control of most micro-CT scanners limit their utility in pulmonary imaging. Carbon nanotubes (CNTs) have permitted the development of field emission cathodes, with rapid switching and precise pulse control. The goal of this study was to explore the utility of a CNT-based micro-CT system for application in quantitative pulmonary imaging. Materials and Methods: Twelve CB57/B6 mice were imaged during peak inspiration and end-exhalation using the CNT micro-CT system. The respiratory trace was derived from a sensor placed underneath the abdomen of the animal. Animals were allowed to breathe freely during the imaging under isoflurane anesthesia. Images were reconstructed using isotropic voxels of 77-μm resolution (50 kVp, 400 projections, 30-ms x-ray pulse). Lung volumes were measured with region-growing techniques and thresholds derived from the surrounding air and soft tissues. Basic functional parameters, including tidal volume, functional reserve capacity and minute volume, were also calculated. Results: The average scan time was 13.4 ± 1.8 minutes for each phase of the respiratory cycle. Mean lung volumes at peak inspiration and end-expiration were 0.23 ± 0.026 and 0.11 ± 0.024 mL, respectively. The average minute volume was 11.93 ± 2.64 mL/min. Conclusions: The results of this study demonstrate the utility of a CNT-based micro-CT system in acquiring prospectively gated images from free-breathing mice for obtaining physiologic data. This technique provides an alternative to breath-hold techniques requiring intubation and offers greater dose efficiency than retrospective gating techniques. [ABSTRACT FROM AUTHOR]

Background: Anthocyanins are potent antioxidants that are widely distributed in fruit, vegetables, and red wines. Anthocy-anin products are also prescribed as medicines in many countries for treating various diseases. However, the pharmacokinetics of dietary anthocyanins are not known in humans because these glycosides were long considered nonabsorbable. Objective: The objective of this study was to determine whether anthocyanins can be absorbed as glycosides and to evaluate their pharmacokinetics in humans. Design: Four healthy elderly women consumed 720 mg anthocyanins. A series of blood and urine samples were collected before and after consumption of the anthocyanins. Anthocyanins were measured in plasma and urine by combining an octadecylsi-lane solid-phase extraction for sample preparation and an HPLC system with diode array for anthocyanin separation and detection. The structures of anthocyanins as glycosides in plasma and urine were further confirmed by using liquid chromatography-mass spectrometry. Results: Anthocyanins were detected as glycosides in plasma and urine. The maximum plasma concentration of total anthocyanins varied from 55.3 to 168.3 nmol/L, with an average of 97.4 nmol/L, and was reached within 71.3 min. The elimination of plasma anthocyanins appeared to follow first-order kinetics. The elimination half-life of plasma total anthocyanins was calculated to be 132.6 min. Most anthocyanin compounds were excreted in urine during the first 4 h. The excretion rate of total anthocyanins was 77 (µg/h during the first 4 h and 13 (xg/h during the second 4 h. Conclusion: Anthocyanins are absorbed in their unchanged glycated forms in elderly women. [ABSTRACT FROM AUTHOR]

Presents a study which examined the possible affects a diet rich in fruit and vegetables can have on the antioxidant capacity of human plasma. What the increased consumption of fruit and vegetables has been associated with; Measurement of the antioxidant capacity; Determination of the plasma antioxidant capacity.

Microspherical ZnO composites were prepared by introducing carbon dots (CDs) in situ by a one-step hydrothermal method. The effects of precursor and calcination treatments on the microstructure and morphology, compositional features and triethylamine (TEA) detection were carefully investigated. The results show that the addition of excess urea promotes the formation of CDs, the produced UC-ZnO composite presents microspheres with relatively smooth surface after calcination, and the retained CDs form heterojunctions with ZnO. TC-ZnO composite produced by adding excess trisodium citrate displays bowl-shaped depressions on the surface. After calcination, the porous structures with large specific surface area and carbon incorporation are achieved. The two composites show improved gas-sensitive response and reduced detection limit for TEA. The sensitivity for 100 ppm TEA at the optimal operating temperature of 350°C is 357 for UC-ZnO and 526 for TC-ZnO sensor, which are 21% and 80% higher than that of pure ZnO, respectively. The TC-ZnO sensor possesses an excellent low detection limit of 32 ppb. The introduction of CDs effectively modulates the morphology and interface state of ZnO microspheres, and improves the gas-sensitive performance. [ABSTRACT FROM AUTHOR]

Pt-loaded curling-like Bi 2 WO 6 (BWO) microdiscs were fabricated via a simple one-step hydrothermal and impregnation route. Various characterization methods, such as XRD, EDS and TEM, were conducted to prove the successful Pt loading. Electron migration from the semiconductor BWO to the precious metal Pt was revealed by the blue shift of the Bi 4f and W 4f XPS peaks with the increase of the Pt loading amount and the ∼10-fold baseline resistance elevation of the BWO-based sensor by the Pt loading, proving the formation of Schottky junction. Among the pristine BWO and Pt-loaded BWO with different Pt loading amounts, 1 wt % Pt-loaded BWO exhibits the highest gas response of 209 in sensing 500 ppm triethylamine at 300 °C, a minimal selectivity coefficient of 130.6 against some typical interfering gases at the same concentration and a low detection threshold of 1 ppm. Additionally, the sensitization mechanism is discussed as the synergistic effect of noble metal catalytic effect and metal-semiconductor junctions. [Display omitted] [ABSTRACT FROM AUTHOR]

CaCu 3 Ti 4 O 12 (CCTO) materials are greatly desired in the miniaturized multilayer devices due to the giant permittivity. However, Ni electrode presently cannot be employed as internal electrode for CCTO-based multilayer devices, which is much cheaper than Ag/Pd electrode. This is because Ni electrode should be sintered in protecting atmosphere, which easily led to decomposition of CCTO materials. The decomposition reaction was mainly attributed to the serious Cu-loss during reduction sintering. The Cu-loss can be effectively weakened, when the ceramics were sintered in a close alumina crucible at a relatively low temperature induced by liquid phase. The decomposition reaction was found to be suppressed and dense ceramics were successfully prepared by reduction sintering. Giant permittivity was observed in the reduced CCTO-BN (4.2 × 104), but dielectric loss (8.88) and nonlinear characteristic deteriorated. This is because the grain boundary could not be oxidized during reduction sintering. The reduced CCTO-BN was then reoxidized in air to promote the oxidation of grain boundary. The dielectric loss was decreased more than 102 times to 0.07 and the nonlinear characteristic was reestablished for the reoxidized CCTO-BN. Meanwhile, the relative permittivity still remained a giant value of 1.2 × 104. The findings shed a new light on developing CCTO-based devices with Ni electrode, which helps to significantly reduce the production cost. [ABSTRACT FROM AUTHOR]

Abstract: Effects of doping molybdenum oxide (MoO3) in copper phthalocyanine (CuPc) as hole injection layer in OLEDs are studied. A green OLED with structure of ITO/MoO3-doped CuPc/NPB/10-(2-benzothiazolyl)-2,3,6,7-tetrahydro-1,1,7,7-tetramethyl-1H,5H, 11H-(1)-benzopyropyrano(6,7,8-i,j) quinolizin-11-one (C545T): tris(8-hydroxyquinoline) aluminum (Alq3)/Alq3/LiF/Al shows the driving voltage of 4.4V, and power efficiency of 4.3lm/W at luminance of 100cd/m2. The charge transfer complex between CuPc and MoO3 plays a decisive role in improving the performance of OLEDs. The AFM characterization shows that the doped film owns a better smooth surface, which is also in good agreement with the electrical performance of OLEDs. [Copyright &y& Elsevier]

Abstract: The tandem organic light-emitting diodes (OLEDs) with an effective charge-generation connection structure of Mg-doped tris(8-hydroxyquinoline) aluminum (Alq3)/Molybdenum oxide (MoO3)-doped 3, 4, 9, 10-perylenetetracarboxylic dianhydride (PTCDA) were presented. At a current density of 50 mA/cm2, the current efficiency of the tandem OLED with two standard NPB/Alq3 emitting units is 4.2 cd/A, which is 1.7 times greater than that of the single EL device. The tandem OLED with the similar connection structure of Mg-doped PTCDA/ MoO3-doped PTCDA was also fabricated and the influences of the different connection units on the current efficiency of the tandem OLED were discussed as well. [ABSTRACT FROM AUTHOR]

Thermodynamically stable C 3 N phases in the pressure range of 0–100 GPa are searched and calculated by ab initio evolutionary algorithm and density functional theory. Ground-state C 3 N phase at ambient pressure is predicted to be a layered structure with Cmmm space group. The previously reported Fd 3 ¯ m phase exists only in the narrow pressure range of 6.1–7.4 GPa, which transforms into a P 3 ¯ m 1 phase at 7.4 GPa and then into a R 3 ¯ m phase at 40.7 GPa. The increasing pressure drives the R 3 ¯ m phase to a C 2/ c phase at 76.9 GPa. Dynamical and mechanical stabilities of C 3 N phases are checked and confirmed by phonon dispersion and elastic constant calculations. It is diverse of the electronic properties of C 3 N with Cmmm (zero band gap), P 3 ¯ m 1 (wide gap of 4.55 eV), R 3 ¯ m (wide gap of 4.54 eV) and C 2/ c (narrow gap of 1.94 eV). The three-dimensional strong covalent C 2/ c C 3 N is superhard with high hardness of 79.5 and 86.9 GPa calculated by Chen and Gao models. Pressure-temperature phase diagram of C 3 N is firstly established and shows high temperature can significantly decrease synthesis pressures of C 2/ c phase, which gives a theoretical guidance for further experimental synthesis. [ABSTRACT FROM AUTHOR]

• SnO 2 /VO 2 /SnO 2 thermochromic films are prepared by pulsed laser deposition. • Balance between luminous transmittance and solar modulation ability is achieved. • All the SnO 2 /VO 2 /SnO 2 tri-layer films show good hydrophobicity. The SnO 2 /VO 2 /SnO 2 (SVS) multilayer films were prepared using pulsed laser deposition and were characterized by X-ray diffraction, Raman spectroscopy, scanning electron microscopy, Hall Effect Measurement System, double beam spectrophotometer and contact angle measurements. The results showed that SVS multilayer films with excellent thermochromic properties were obtained by adjusting the preparation temperature of the SnO 2 buffer layer and antireflection layer. When the preparation temperature of the SnO 2 layer was 320 °C, the phase transition amplitude (ΔR) of the VO 2 film reached 354 times and both the phase transition temperature (T c) and hysteresis loop width (ΔH) could be effectively reduced. Meanwhile, the SVS multilayer film had satisfactory luminous transmittance (50.2%) and solar modulation ability (15.3%), achieving the balance of optical properties. In addition, all the SVS multilayer films exhibited excellent hydrophobicity. Boiling water experiments show that the service life of SVS tri-layer film is twice that of SV bi-layer film. This work suggests that the SVS multilayer films are a good candidate for VO 2 -based smart windows. [ABSTRACT FROM AUTHOR]

In this study, high-quality thermochromic vanadium dioxide (VO 2) thin films were grown on ZrO 2 /glass by pulsed laser deposition and were investigated using X-ray diffraction (XRD), atomic force microscopy (AFM), double beam spectrophotometry and Hall Effect measurement system. Based on XRD results, it can be inferred that the crystal structure of ZrO 2 buffer layer can be transformed between monoclinic and tetragonal structures with the increase of buffer layer thickness. Photoelectric performance tests showed that the introduction of ZrO 2 buffer layer considerably reduced the phase transition temperature (T c) and hysteresis loop width (Δ H) of the VO 2 films and allowed the visible light transmittance (T lum) and solar modulation ability (Δ T sol) of the films to be tuned effectively. Especially, when the thickness of the ZrO 2 buffer layer was 50 nm, the T c of the VO 2 films reached the minimum value of 48 °C. When the ZrO 2 buffer layer thickness increased to 125 nm, the sheet resistance change of the VO 2 film attained two orders of magnitude, and their T lum-90°C and Δ T sol were as high as 50.01% and 7.88%, respectively. These results showed that the ZrO 2 buffer layer considerably affected the growth of VO 2 films on amorphous glass substrates and was beneficial for the application of VO 2 in energy-saving smart windows. [ABSTRACT FROM AUTHOR]