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In multicellular eukaryotes, autophagy is a conserved process that delivers cellular components to the vacuole or lysosome for recycling during development and stress responses. Induction of autophagy activates AUTOPHAGY-RELATED PROTEIN 1 (ATG1) and ATG13 to form a protein kinase complex that initiates autophagosome formation. However, the detailed molecular mechanism underlying the regulation of this protein complex in plants remains unclear. Here, we determined that in Arabidopsis thaliana, the regulatory proteins 14-3-3λ and 14-3-3κ redundantly modulate autophagy dynamics by facilitating SEVEN IN ABSENTIA OF ARABIDOPSIS THALIANA (SINAT)-mediated proteolysis of ATG13a and ATG13b. 14-3-3λ and 14-3-3κ directly interacted with SINATs and ATG13a/b in vitro and in vivo. Compared to wild-type (WT), the 14-3-3λ 14-3-3κ double mutant showed increased tolerance to nutrient starvation, delayed leaf senescence, and enhanced starvation-induced autophagic vesicles. Moreover, 14-3-3s were required for SINAT1-mediated ubiquitination and degradation of ATG13a. Consistent with their roles in ATG degradation, the 14-3-3λ 14-3-3κ double mutant accumulated higher levels of ATG1a/b/c and ATG13a/b than the WT upon nutrient deprivation. Furthermore, the specific association of 14-3-3s with phosphorylated ATG13a was crucial for ATG13a stability and formation of the ATG1–ATG13 complex. Thus, our findings demonstrate that 14-3-3λ and 14-3-3κ function as molecular adaptors to regulate autophagy by modulating the homeostasis of phosphorylated ATG13.

Aerodynamic optimization of the airfoil is of great significance to the shape design for wind turbine blade. However, it is tough to calculate the aerodynamic forces of airfoil with random shape variations. In response to this challenge, a stochastic parameterized model based on uncertainty quantification method is proposed. And the influence of non-deterministic airfoil geometry caused by designed parameters on the aerodynamic characteristics is evaluated through the combination of sparse grid-based polynomial chaos (SGPC) and computational fluid dynamic (CFD) taking two airfoils at different Reynolds numbers as examples. OpenFOAM is employed as CFD solver and connected with the in-house stochastic parametric analysis code in a non-intrusive way. Finally, the aerodynamic responses of lift, drag, as well as the surface pressure coefficients are obtained, and the sensitivity of the lift and drag coefficients to the stochastic designed parameters are evaluated. It can be concluded that for the same type airfoil, the sensitive parameters after stall behavior are effected to some extent by increasing Reynolds number, that is, the impact of the maximum curvature index on pressure surface is weakened. As for two kinds of airfoils, S809 is sensitive to parameters near the maximum curvature of the airfoil and the trailing edge of the suction surface under attached flow, while convert to those near the leading edge and maximum curvature of suction face once stalled. FFA-W3-241 airfoil has no sensitivity factors in attached flow and features the same sensitive indicators after stall. These results will provide a reference for coarse-to-fine strategy in optimizing the sample library which is generally the first step of airfoil design process.

With the rapid development of cities, the problem of environmental sustainability has become increasingly prominent, and it is increasingly important to build a socially resilient city. This research focuses on white pollution-the recycling of waste plastics in concrete in the city and the comfort of the urban living environment, from the perspective of concrete materials. Firstly, the proportion of recycled plastics, natural aggregate, water-cement ratio, and other parameters were optimized, and then the heat resistance, sound insulation, economic and environmental protection performance of the optimized concrete were studied. The results showed that the optimal proportion of recycled plastic concrete was obtained, and the strength deterioration mechanism was revealed. The maximum suitable use temperature of recycled plastic concrete is around 75 ℃. Recycled plastic concrete has better sound insulation performance for unsteady sound, human sound and mechanical sound. In terms of economic and environmental performance, the cost of raw materials of recycled plastic concrete is not dominant, and the water-soluble extracts have little impact on the environment. The research results are expected to provide a theoretical basis for the realization of urban environmental sustainable development.

For uniform size and transparency, polypropylene fiber was chosen. When using PIV, the velocity from suction to pressure side decreases almost linearly between 1.0Q and 1.3Q. It does, however, fall from the suction side and rise until it reaches the pressure surface at 0.7Q. From the leading edge of the blade to the trailing edge, the spanwise velocity nearly increases linearly. With increasing concentration, the velocity increases slightly on the suction side while decreasing on the pressure side, resulting in a small pressure rise. When the external characteristic data of the pumping process is used, the pump exhibits a small elevation of head. When the concentration is increased from 0.5% to 1.0%, the efficiency gradually increases. The efficiency gradually decreases as the concentration increases from 1.0% to 1.5%. To investigate this discrepancy, a high-speed photographic system was used to examine the distribution of fiber particles in the impeller’s channels.

During the post-classification for raster land cover updating, manual data inconsistency checking is labour-intensive and time-consuming. To address this issue, a spatial relationships-based data i...

The calculative width directly affecting the horizontal bearing capacity of the pile is an important parameter of the horizontal loaded pile foundation and its effective value will change with the variation of slope angle. In order to research the effect of slope on calculative width, 4 groups of model test under static lateral loading with different slope angles were carried out indoor. Based on the PIV system, the horizontal diffusion angle was obtained by the quantitative analysis of the vectorial displacement field of soil around the pile. The calculative width of pile under 4 slopes was then calculated based on the Horizontal Diffusion Principle. Compared with numerical simulation and full-scale test, calculative width based on Horizontal Diffusion Principle is greater than that based on the code of China (JGJ94-2008) and it decreases by about 3.3 m by every 10° increase of slope. After correcting the calculative width based on Horizontal Diffusion Principle, m-value that can characterize the horizontal resistance of the pile is greater than that based on the code of China (JGJ94-2008); the average difference of two m-values is about 75 MN/m4. Slope has a strong weakening effect on m-value. These conclusions provide a certain reference for the selection of calculative width in engineering.

ObjectivesTo characterize the genetic environment of the carbapenem resistance determinant in Proteus vulgaris of swine origin.MethodsThe carbapenem-resistant P. vulgaris strain BC22 was isolated from a faecal swab from a diseased pig with diarrhoea in Sichuan Province of China in 2018. The presence of carbapenemase genes was screened by PCR. WGS and bioinformatics analysis were performed to analyse the genetic environment of the carbapenem resistance determinant.ResultsP. vulgaris strain BC22 was found to harbour the carbapenemase gene blaNDM-1. WGS data revealed that blaNDM-1 was located in a truncated ISAba125 composite transposon. The carbapenem resistance gene blaNDM-1 and 20 other resistance genes, including the multiresistance gene cfr and the bifunctional aminoglycoside/quinolone resistance gene aac(6′)-lb-cr, were located in a novel SXT/R391 integrative and conjugative element (ICE). This new SXT/R391 ICE of 148.7 kb was chromosomally located, and could be transferred to Escherichia coli.ConclusionsHere, we report a carbapenemase gene, blaNDM-1, integrated into an SXT/R391 ICE. Our study highlights that this SXT/R391 ICE may facilitate the dissemination of clinically important resistance genes such as blaNDM-1, cfr and aac(6′)-lb-cr.

In this paper, the flow control system consists of some small microflaps located between the rear fins of the projectile. These microflaps can alter the flow field in the finned region of the projectile resulting in asymmetric pressure distribution and thus producing control forces and moments, furthermore to provide directional control for a supersonic projectile. Due to the small size and high speed characteristics of projectile, which is with fast and valid response characteristics, this flow control system has initially shown excellent potential in terms of supersonic flow control. The CFD simulation used here solves steady-state Reynolds-averaged Navier-Stokes equation with two-equation turbulence model k-ε. Firstly, we investigate the flow mechanism around microflap in supersonic flow, the flow fields around the microflap are complex, involving three-dimensional shock-shock, shock-boundary layer interactions. Secondly, for the microflap and the fin of Basic Finner configuration, the influence of microflap geometric parameters, microflap locations on aerodynamics is obtained and the interference mechanism is explored. Finally, several typical roll and pitch control layouts are described. According to the simulation results and their analysis, some preliminary conclusions can be drawn: by analyzing the flow interference mechanism between microflap and the fin, we find that the separated shocks ahead of the microflap, the bow shocks around microflap, and the trailing-edge wake, have influences on fin's surface pressure; among these factors, the bow shocks are stronger than separated shocks, furthermore it can generate larger high pressure region. Then we find out the aerodynamic characteristics of several typical control layouts at a supersonic speed, Ma=2.5, furthermore, hence nearly 4.8% drag is increase compared with the condition without microflap. As the number of microflaps increasing, the control aerodynamic forces and moments increases almost linearly. With a proper layout of the microflap's location, quick change in the surface pressure distribution can be achieved for rear fins of the projectile, the microflap should be mounted that can increase the high pressure zone, meanwhile, reduce the low pressure zone on the surface of fins, thus modulating the projectile's attitude can be realized.

To study the influence of fiber particles on the flow field within the passages of an open impeller centrifugal pump, an experiment was performed. The hair fiber was used as solid particle phase in this experiment. After measuring the performance characteristic and PIV data, the flow field in impeller was measured and analyzed. It was shown that at the concentration of 0.1%, a varied distribution of relative velocity from different flow channels was observed. The outlet velocity of the impeller in the second flow channel was obviously higher than that in the first flow channel. The variation of the relative velocity near the hub tended to be consistent at the position of the front plane and the middle plane of the impeller. At 0.2% concentration, the relative velocity at the suction surface of the two channels changes more sharply than the other positions. Within the second channel, it was found that the relative velocity under low flow condition was obviously higher than that under rated and large flow rates. Under different concentrations, the increase of the relative velocity at low flow rate changed intensely compared with the other two conditions. The low velocity zone will be formed near the middle part of the suction surface of the flow channel which gradually decreases with the increase of the flow rate. The external characteristic test shows that the efficiency of the pump and the drag reducing feature increase with the increase of concentration.

The Ho2Fe17-xSix (x=0.0, 0.1, 0.2, 0.3) alloys were prepared by arc melting and high energy ball milling method. The influence of the Si substitution on phase structure, morphology and electromagnetic parameters were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM) and vector network analyzer (VNA), respectively. The results show that the Ho-Fe-Si particles are flaky after the ball milling. The minimum absorption peak frequency shifts towards a lower frequency region with the increasing of Si content. The minimum RL of Ho2Fe16.7Si0.3 reaches-42.96 dB at 9.76 GHz, and the frequency bandwidth of R

In this study, whether H9N2 influenza A virus (IAV) infection contributed to secondary Klebsiella pneumoniae infection was investigated. From post-infection onwards, clinical symptoms were monitored, examined and recorded daily for 11 days. As a result, no clinical signs were observed in the mice infected with single H9N2 IAV, implying that H9N2 IAV was less pathogenic to mice. Compared to single K. pneumonia infection, K. pneumoniae infection following H9N2 IAV infection exacerbates lung histopathological lesions and apoptosis, resulting in more severe diseases. Lung index of the mice with H9N2 IAV and K. pneumoniae co-infection was significantly higher than those in the other groups. Bacterial loads in the tissues in H9N2 IAV and K. pneumoniae co-infection group were significantly higher than those in the single K. pneumoniae infection group at 7 dpi. It demonstrated that prior H9N2 IAV infection contributed to K. pneumonia proliferation and delayed bacterial clearance in mice. Secondary K. pneumoniae infection influences seroconversion of anti-H9N2 antibody titers and the cytokine profiles. The findings demonstrated that H9N2 IAV infection facilitated secondary K. pneumonia infection, causing severe the diseases in mice.

The hybrid method (HM) presented in this article assembles the high-resolution finite volume method (HRFVM) and the standard method of moments (SMOM) with an accurate inversion technique for determining the crystal size distribution (CSD), providing a computationally efficient solution with reliable accuracy for one-dimensional population balance modeling in batch thermocycling crystallizations. Two chemical systems, paracetamol and L-ascorbic acid, are chosen to study the accuracy and computational efficiency of the approach in the unseeded and seeded cases, respectively. Comparisons between the HRFVM and the HM are made for different temperature profiles in both cases. In addition, the compiled C/Mex files (MXFs) are implemented to further minimize the run time of the HM, and the benefits of the compiled files are discussed compared to the MATLAB files (MAFs).

The aeroelastic modeling of Tjaereborg wind turbine blades was performed based on the unsteady Reynolds Averaged Navier-Stokes equations (URANS) combined with Finite Element Method (FEM) in a loosely coupled manner. This method was verified by comparing numerical and experiment results at four axial inflow wind speeds. Furthermore, the aeroelastic performance of Tjaereborg wind turbine under yaw angle of 10°, 30° and 60°were computed and analyzed. The results showed that the average power and thrust of the wind turbine decreased with increasing yaw angle, along with the increasing oscillation amplitude under large yaw angle. The aerodynamic load showed periodic change within one revolution of rotor, resulting in the blade deflection and the strain present considerably asymmetric distributions. The maximum deflection and strain occurred at azimuth angle of about90° and their minimum values occurred at azimuth angle of about 270°. Besides, both the maximum deflection and strain under yaw conditions became larger than those in axial inflow condition do. For Tjaereborg wind turbine, the coupled solver gave a higher average power and thrust than the CFD solver alone. The aerodynamic performances showed more asymmetrical characters under the combined effect of yaw and fluid structure interaction (FSI).

The effect of seed loading and batch trajectory on the growth of crystals with two size coordinates is studied using a simple model for two crystallization systems known to exhibit shape evolution: hen egg white lysozyme and hydroquinone. For moderate seed loading, batch trajectories that lead to a high supersaturation near the beginning of the batch result in a larger nucleated mass and less growth of the seed crystals than other alternatives, while trajectories that keep the supersaturation almost constant give good performance. Increasing seed mass and decreasing seed size also improves performance. Critical seed loading analysis shows that the two-dimensional systems considered in this work behave similarly to one-dimensional crystallization systems considered previously.

The Nd7.69Fe92.31-xTix (x = 0, 4, 8, 12) alloy were prepared by arc smelting and high energy ball milling method. The morphology and phase structure of the powders were analyzed by Scanning Electron Microscope (SEM), X-ray diffraction (XRD) and the effect of the Ti content on microwave absorbing properties of the powders were measured by a vector network analyzer (VNA). The results reveal that the samples mainly consisted of Nd2Fe17 and α-Fe crystal structure. The minimum absorption peak frequency shifts to lower frequency region firstly and then shifts to higher frequency region with the increasing amount of Ti content. The minimum reflection loss of Nd7.69Fe84.31Ti8 powder is-31.35 dB and the bandwidth of R < -5 dB reach 3.6 GHz when the coating thickness is 2.0 mm. With the increasing of the coating thickness, the minimum reflectivity peak value of the Nd7.69Fe84.31Ti8 moves to lower frequency region and the minimum reflection loss increase firstly and then decrease. And the minimum reflection value of Nd7.69Fe84.31Ti8 alloy can reach to-38.74 dB (microwave absorption rate 99.99%) at 5.68 GHz, and the bandwidth of R < -10 dB reach 1.12 GHz with the best matching thickness of 2.2 mm.

The wake of a wind turbine has substantial influence on the aerodynamic performance of downstream wind turbine. Unsteady numerical simulations are performed in this paper to investigate the wake structure of a three-bladed H-type VAWT (vertical axis wind turbine) and the influence on the aerodynamic performance of downstream wind turbine. A simplified two-dimensional model is used considering the blades are straight. Unsteady Reynolds Averaged Navier–Stokes equations are solved using FlowVision software, which uses dynamic grid method to handle the blade rotation. The SST turbulence model is used for turbulence modeling. The distance between two wind turbines is from 5D to 17D with 2D intervals, where D denotes the wind turbine diameter. The wind speed is 5.07 m/s, corresponding to a tip speed ratio of 2.15. The power coefficients of two wind turbines are compared in detail. The discussions focus on the periodic variations of the aerodynamic performance and flow variables of two turbines with two typical distances, i.e., 7D and 15D, respectively. The simulation results show that the velocity recovery distance needed for a VAWT is usually larger than 15D.

MnAlFe alloy was prepared by the combined use of smelting, high-energy ball milling and tempering heat treatment process. The phase composition and microwave absorbing properties of MnAlFe alloy were investigated by X-ray diffractometer(XRD) and vector network analyzer. The results show that the powders consist of Al8Mn5 single phase with different Fe content; the dielectric loss and the magnetic loss increases with the addition of Fe, the resonant frequency and absorption peak of ε″ and μ″ moves towardslower frequency region simultaneously. The (Al8Mn5)99Fe exhibits preferably comprehensive microwave absorbing properties in the range of 6-18 GHz. The value of the minimum reflectivity and absorption peak frequency with the coating thickness of 1.5 mm, are -23.1 dB, 15.04 GHz respectively. Owing to the wide applications of electromagnetic waves in the range of 1–4 GHz for mobile phone, local area network, radar systems and so on over the past few decades, the serious problems of the electromagnetic interference and electromagnetic compatibility have become increasingly prominent in recent years. Microwave absorbing materials, which possess special performance for absorbing electromagnetic wave, have been applied in both civil and military fields and play an important role in camouflage technology. In military field, stealth technology to reduce and eliminate the electromagnetic radiation and electromagnetic interference resulting from the broad applications of various kinds of electronic and microwave instruments, stealth technology plays an important strategic role in the wars in future[1-2]. The microwave absorbing materials can be used to reduce radar cross section for military use. For this reason, the microwave absorbing material is vitally important for both civil and military fields[3-7]. In view of this utilization, excellent microwave absorbing materials should exhibit strong microwave absorption properties over a wide frequency range and need to be thin and light in weight. It has an important meaning to the application of magnetic microwave absorbing materials. MnAl alloy can be used as microwave absorbent. It has properties such as light in weight, good thermal stability and corrosion resistance[8-11]. But as permanent magnets, MnAl has shortcomings such as their difficulties of fabrication and high costs that prevent them from being used as permanent magnets. A great value would be brought to either theory or practice through proper treatments as further improvement in properties. In this paper, we will discuss the effects of changing relative content of Fe on absorption properties of Al8Mn5 alloy.

In a smart grid, electricity energy demands requested from down-stream sectors continuously increase. One way to meet the energy demands is utilizing a Non-Intrusive Load Monitoring (NILM)-style system to monitor and manage residential and commercial electrical appliances in respond to demand response programs. NILM is as an electricity energy audit to energy-saving issues.This paper aims at developing an NILM identification considering the influence of voltage variations. An NILM system normally consists of "Data Acquisition", "Event Detection and Feature Extraction", and "Load Classification." The goal of load classification in NILM is to identify the operation ON/OFF status of individual household appliances. The k-Nearest Neighbors Classifier is used as the load classifier of the NILM. In NILM, measured physical phenomena, voltage signals/power profiles, to load classification for long-term load monitoring vary. The variations affect the identification performance. In this paper, a cross-validation strategy is conducted and used to deal with sampled data with systematic errors from classified loads. Different types of loads are used to verify the influence of the voltage variations to load identifications. As the experimentation reported in this paper shows, a satisfactory recognition rate of 97.60% to the NILM load identification addressed in this paper is achieved. The proposed NILM system is able to classify loads with proper robustness.

In terms of distance function and spatial continuity in Voronoi diagram, a generic generating method of Voronoi diagram, named statistical Voronoi diagram, is proposed in this paper based upon statistics with mean vector and covariance matrix. Besides, in order to make good on the discreteness of spatial Voronoi cell, the cross Voronoi cell accomplished the discrete ranges in its continuous domain. In the light of Mahalanobis distance, not only ordinary Voronoi and weighted Voronoi are implemented, but also the theory of Voronoi diagram is improved further. Last but not least, through Gaussian distribution on spatial data, the validation and soundness of this method are proofed by empirical results.

This paper mainly focuses on the modeling and simulation of the doubly fed induction generator (DFIG) based wind turbine generation system. In this paper, a new method which combines the mechanical part and electrical part is presented to model the wind turbine generation system. The turbine rotor blade is modeled by the lifting line model and the aerodynamic forces are solved by the improved free vortex wakes method with the supplementary of two dimensional aerodynamic data (three dimensional corrected). The control system of pitching and generator with voltage oriented control (VOC) are established in Matlab/Simulink. The drive train is also modeled with two mass model. In order to realize the coupling computation of the wind turbine model, a data link is built to transfer the parameters between aerodynamic part and electrical part. In this way, the interaction between turbine rotor and generator could be predicted. The validations are firstly made to ensure the reliability of the model. Then the performance of a 1.5 MW wind turbine is investigated with this integrated model under different wind and symmetrical grid voltage dip condition.

The unsteady wake effect of upstream wind turbine on the aerodynamic performance of downstream wind turbine is investigated using CFD simulations in this paper with two two-dimensional models of H-type wind turbine of three same blades. Dynamic grids based on the inertial coordinate system are employed and the SST turbulence model is used for turbulence modeling. The wind speed is 5.07 m/s and the tip speed ratio is 2.15. The distance between upstream and downstream wind turbine is 5D, 7D, 9D, 11D, 13D, 15D and 17D (D denotes the diameter of the wind turbine). The power coefficient of upstream and downstream wind turbine is comparative analyzed. The variation of the tangential force coefficient of single blade with azimuth and the velocity distribution of different locations of the wind turbine wake are discussed in detail with the distance between upstream and downstream wind turbine of 7D and 15D. In addition, two-dimensional unsteady viscous flow field through velocity contours in one circle is presented.

To be able to more accurate analysis aerodynamic characteristic variation under yaw of NREL Phase VI wind turbine. The influence of yaw on the aerodynamic characteristic by using a three-dimensional unsteady CFD methods based sliding mesh in this paper. To flow, the overall performance and Cp of the three-dimensional flow numerical simulation were compared with experimental results with the same wind speeds to confirm the reliability of the model at a given axial wind speed conditions. In the yaw conditions, the effect of yaw on the aerodynamic performance of wind turbine blades, changing law and reveal the aerodynamic performance is in the flow details and rules in different azimuth.

Detached eddy simulation (DES) with wall function was used in the flow simulation over complex terrain. Bolund Island with an almost vertical upstream escarpment was simulated, which has abundant measurements. Different density grids with the same size domain were employed. Flow structure details and good results can be obtained when the grid size is a twentieth or smaller than the height of the island in large separation region, when using central scheme. DES has better performance than RANS in large separation region.

In order to accurately analysis the aerodynamic characteristic variations of wind turbines under shear, the influence of axial and shear on the aerodynamic characteristic of a horizontal-axis wind turbine is simulated in this paper by using a sliding grid method based on FlowVision. By using the TJÆREBORG wind turbine as the object of study, a three-dimensional model of a uniform wind flow can be created. The CFD calculation results, the experimental results and the Bladed results can be used to confirm the reliability of the model. In order to investigate the effect of wind shear with regard to three-dimensional unsteady flow characteristics and a three-dimensional flow field in a wind turbine impeller, an analysis of wheel wind speed of 11m/s and an investigation of the influence of wind shear on turbine performance are carried out.

According to the characteristics of cage wind turbines’ dynamic characteristics which change following the wind speed changes, the dynamic mathematical models of cage wind turbines major subsystems have been established, including the aerodynamic subsystem model, drive train subsystem model and generator subsystem model. Then these nonlinear dynamic models with time-varying parameters have been integrated and linearized to obtain the whole linear time-varying parameters dynamic mathematical model. To take the 2MW cage wind turbines wind turbine as example, the proposed model is validated by the study on the dynamic characteristics of cage wind turbines with wind speed variation , and the results show that the proposed model could provide a theoretical support for optimal control of the cage wind turbines.

In this paper, non-deterministic CFD (computational fluid dynamics) simulations have been performed to investigate the uncertain effects of stochastic boundary conditions on the aerodynamic performance of wind turbines. A NIPRC (non-intrusive probabilistic collocation) method is employed, which is coupled with a commercial flow solver. A 2D (two-dimensional) airfoil case is used to validate the non-deterministic simulation, where the angle of attack is considered as an uncertain parameter in a Gaussian distribution. The simulation results are compared with Monte Carlo simulation results. Based on the validation, non-deterministic CFD simulations were performed on a 3D (three-dimensional) wind turbine blades case, where the wind speed is considered as an uncertain parameter. The discussions mainly focus on the total performance variations and the uncertainty propagation in the fluid field. The simulation results show that the input uncertainty of the inlet velocity results in a high variation zone in the pressure distribution near the blade root, and which decreases from the root to the tip. With the wind speed increases, flow separation is observed. The separation vortex regions correspond to the maximum variation area, and the maximum variation extends to the trailing edge even to the whole suction side.

The aerodynamic performance and the bypass flow field of a vertical axis wind turbine under self-starting are investigated using CFD simulations in this paper. The influence of pitch angle variations on the performance of the wind turbine during self-starting is presented. A two-dimensional model of the wind turbine with three blades is employed. A commercial software FlowVision is employed in this paper, which uses dynamic Cartesian grid. The SST turbulence model is used for turbulence modeling, which assumes the flow full turbulent. Based on the comparison between the computed time-dependent variations of the rotation speed with the experimental data, the time-dependent variations of the torque are presented. The characteristics of self-starting of the wind turbine are analyzed with the pitch angle of 0o、-2oand 2o. The influence of pitch angle variations on two-dimensional unsteady viscous flow field through velocity contours is discussed in detail.

In this paper, a dynamic stall control scheme for vertical-axis wind turbine (VAWT) based on pulsed dielectric-barrier-discharge (DBD) plasma actuation is proposed using computational fluid dynamics (CFD). The trend of the wind turbine power coefficient with the tip speed ratio is verified, and the numerical simulation can describe the typical dynamic stall process of the H-type VAWT. The tangential force coefficient and vorticity contours of the blade are compared, and the regular pattern of the VAWT dynamic stall under different tip speed ratios is obtained. Based on the understanding the dynamic stall phenomenon in flow field, the effect of the azimuth of the plasma actuation on the VAWT power is studied. The results show that the azimuth interval of the dynamic stall is approximately 60° or 80° by the different tip speed ratio. The pulsed plasma actuation can suppress dynamic stall. The actuation is optimally applied for the azimuthal position of 60° to 120°.

In the present paper, the non-intrusive Probabilistic Collocation (NIRPC) method is introduced in detail and used to simulate the effects of tip clearance uncertainty on the aerodynamic performance of NASA Rotor 37, which is combined with a commercial CFD software. The tip clearance height is supposed to be a stochastic variable in Beta distribution with four schemes of uncertainty in the random height of the plain tip clearance, the leading edge, the trailing edge and both the leading and trailing edges, respectively. The statistical properties of total performance of the rotor and flow structure within the blade passage in different flow conditions are analyzed. The results show that the Std. of total performances caused by the uncertain plain tip clearance decreases with reducing of the outlet pressure. The maximum of the standard deviation of Mach number appears in the regions where the leakage flow, the shock wave and the separation flow locate, which decreases from the tip to the hub. When the tip clearance is linear distributed, the uncertainty of tip clearance height at the leading edge is the main factor under high mass flow conditions. With the mass flow reaches to choking point, the Std. of total performances caused by the uncertainty of tip clearance height at the trailing edge drops sharply.

Vortex generators (VGs) are an effective way to control flow separation in wind turbine. To understand the mechanism of VGs controlling flow separation, the flow field around airfoil Du97W300 with VGs was simulated and analyzed with CFD tools, and this numerical method is validated through the comparison between the numerical results and the experimental results. Furthermore, the flow fields around airfoil equipped with four different types of VGs are calculated and analyzed. The results show that the helical vortex induced by counter-rotating VGs develop approximately along streamwise direction; these types of VGs can cause a delay in stall and enhance the maximum airfoil lift coefficient. However the helical induced vortex actuated by the co-rotating VGs develop nearly along vortex generator direction and cannot cause a delay in stall effectively. In the counter-rotating VGs, the Q integration (the character parameter of induced vortex) of rectangular is twice of the triangle, and the Q integration of the forward triangle is almost equal to the backward triangle VGs.

The present study focuses on the experimental and numerical investigation of heat transfer performance downstream of the cooling holes on a flat plate with zero streamwise pressure gradient. The experiment was conducted in a low speed wind tunnel. The holes are circular in either straight or curved shape with an angle of 90°. In the experiments, both local and transverse averaged cooling effectiveness and heat transfer coefficient in the surface are studied for single and multiple holes in a row over a range of blowing ratio from 0.5 to 1.22 for single hole and 0.32–1.18 for multiple holes. Surface temperatures downstream of the injection were measured by means of thermal liquid crystals (TLC) and its associated camera system. Numerical simulation were perform for single hole at blowing ratios 0.51 and 1.04 by using Detached Eddy Simulation (DES) method based on S–A one equation turbulence model. In comparison with the straight hole, the curved one shows better overall performance expressed by net heat flux reduction (NHFR) based on both the experimental and numerical results, such as a better transverse spreading, higher cooling effectiveness and an increased local heat transfer coefficient are concluded for the curved hole.

Daily air quality index (AQI) of 161 Chinese cities obtained from the Ministry of Environmental Protection of China in 2015 is conducted. In this study, to better explore spatial distribution and regional characteristic of AQI, global and local spatial autocorrelation is utilized. Pearson's correlation is introduced to determine the influence of single urban indicator on AQI value. Meanwhile, multiple linear stepwise regression is chosen to estimate quantitatively the most influential urban indicators on AQI. The spatial autocorrelation analysis indicates that the AQI value of Chinese 161 cities shows a spatial dependency. Higher AQI is mainly located in north and northwest regions, whereas low AQI is concentrated in the south and the Qinghai-Tibet regions. The low AQI and high AQI values in China both exhibit relative immobility through seasonal variation. The influence degree of three adverse urban driving factors on AQI value is ranked from high to low: coal consumption of manufacturing > building area > coal consumption of the power industry. It is worth noting that the risk of exposed population to poor quality is greater in the northern region than in other regions. The results of the study provide a reference for the formulation of urban policy and improvement of air quality in China.

The aerodynamic performance of a compressor is highly sensitive to uncertain working conditions. This paper presents an efficient robust aerodynamic optimization method based on non-deterministic computational fluid dynamic (CFD) simulation and Multi-Objective Genetic Algorithm (MOGA). A NonIntrusive Polynomial Chaos method is used in conjunction with an existing well-verified CFD module to quantify the uncertainty propagation in the flow field. This method is validated by comparing with a Monte Carlo (MC) method through full three dimensional CFD simulations on an axial compressor (NASA rotor 37). Based on the validation, the non-deterministic CFD is coupled with a surrogate-based MOGA to search for the Pareto front. A practical engineering application is implemented to the robust aerodynamic optimization of rotor 37 under random outlet static pressure. Two curve angles and two sweep angles at tip and hub are used as design variables. Convergence analysis shows that the surrogate-based MOGA can obtain the Pareto front properly. Significant improvements of both mean and variance of the efficiency are achieved by the robust optimization. The comparison of the robust optimization results with that of the initial design and a deterministic optimization demonstrate that the proposed method can be applied to turbomachinery successfully. Copyright c © 2011 John Wiley & Sons, Ltd.

Traditional median filter algorithm has the long processing time, which goes against the real-time image processing. According to its shortcomings, this paper puts forward the rapid median filter algorithm, and uses DE2 board of the company called Altera to do the realization on FPGA (CycloneII 2C35). The experimental results show that the image pre-processing system is able to complete a variety of high-level image algorithms in milliseconds, and FPGA's parallel processing capability and pipeline operations can dramatically improve the speed of image processing, so the FPGA-based image processing system has broad prospects for development．

In order to assess the influences of curved hole passage on cooling effectiveness and flow structure of turbine blade leading edge, the detached eddy simulation is applied to numerically investigate the AGTB turbine cascade under the condition of global blowing ratio M=0.7. The straight or curved cooling holes are located at either the pressure or suction side near the leading edge. The analysis and discussion focus on the local turbulence structure; influence of pressure gradient on the structure, and distribution of cooling effectiveness on the blade surface. The numerical results show that cooling hole with curved passage could bring positive impact on the increase of the local cooling effectiveness. On the suction side, the increased cooling effectiveness could be about 82% and about 77% on the pressure side, compared to the conventional straight hole.

The buildings of domestic wear the upper floors and an underground in-depth reconciliation tendency to do and the possibility of fire occurrence at the time of formation accident is coming to be high. Therefore will be scattered to various place and is established and prevention of disaster information of the receiver which will integrate there is a necessity which will manage. In this paper away where each receiver is installed in the fire for the remote monitoring and controld able to connect to the Internet and fiber optic cable that can be networked fire receiver and control desk was constructed. Between each device can be used by the fire, and more depending on the status of monitoring and alarm, control and maintenance can be performed to develop an integrated management system. The system is evaluated by the criteria of the KFI, and for each segment of the signal propagation time to perform experiments confirmed the reliability of the performance.

In the trend of miniaturization narrow frame and fine wiring structure,the TFT-LCD tends to developing for large margin of design and high real substrate utilization rate.The passivation layer deposit parameters were changed to decrease the size of via hole which connected the pixel electrode and drain electrode were studied.Through the experiments design of changing main parameters to minimize via hole of passivation layer(haze,undercut,Top-PVX deposit thickness,Top-PVX deposit pressure),a solution to minimize the via hole about 20%~30% without changing the etch conditions was found.The electronic parameter measurement was evaluated(Ion,Ioff,Vth,Mobility) and finally one better solution to minimize via hole size was obtained.Therefore,the products quality was improved also.

The isothermal section of the phase diagram of the ternary system Y–Fe–V at 773 K was investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersion spectroscopy (EDS) techniques. It consists of 9 single-phase regions, 16 two-phase regions and 8 three-phase regions. The ternary compound YFe12-xVx (1.5≤x≤2.7, space group I4/mmm) with Mn12Th-type structure was confirmed in this system. At 773 K, the maximum solid solubility of V in Fe, and YFe2, is about 23 at.%, and 3 at.%, respectively, Fe in V is about 22 at.%. And that of Y in Fe, FeV and V don′t exceed 1 at.%.

The NdFe magnetic absorbing materials were prepared by rapid solidification and high-energy ball milling method. The effect of high-energy ball milling on particle morphology, organizational structure and microwave absorbing properties of NdFe magnetic absorbing materials were analyzed with the aid of X-ray diffractometer, scanning electron microscope and vector network analysis. The results show that the Nd2Fe17 and α-Fe phase are refined, the particles become smaller and thinner; the span-ratio of the particles increases along with time during the process of high-energy ball milling; and meanwhile, the frequency of absorbing peak reduces. The absorbing bandwidth broadens as the increase of the time of ball milling, except that of 48h.The minimum reflectance of the powder decreases from -22dB to - 44dB under the circumstances that the time of high energy ball milling reaches 48h and the thickness of the microwave absorbing coating is 1.5mm. But it rebounds to about - 6dB when the time of ball milling reaches 72h.

Remotely sensed data have become a valuable source of data for mapping regional or global land cover. Referable to the spectral complexity and the quality of remotely sensed data selected, classification errors usually occurred in land cover mapping, where the errors occurred can result in an issue in which the spatial heterogeneity in remotely sensed data is inconsistent with that in land cover data. To ensure data quality, land cover data checking mainly depends on manual labor, which is time-consuming and labor-intensive. To tackle this issue, a spatial heterogeneity-based Voronoi matching method for automated detection of land cover data inconsistency is proposed. First, Harris corner-based Voronoi diagrams (HCVDs) are constructed utilizing the image noise filter and Harris corner detector. Second, the regional statistics of range on land cover data using HCVDs is calculated. Ultimately, by matching the heterogeneity in HCVDs and using HCVDs-based first-order neighbor filter, where inconsistent spatial heterogeneity occurs in land cover data can be found. A GlobeLand30 case study from Linqu County, Shandong, for the year 2010 in China is carried out. After detection and validation, this method is shown to be workable for detecting spatial regions where inconsistent spatial heterogeneity occurs in land cover data, and the data quality is improved by 6.3% in this study area after manual verification.