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Anterior cruciate ligament injury (ACLI) is a common sports injury of the knee joint, and ACLI patients often develop early knee osteoarthritis (KOA) after surgery. This may be due to the activation of a post-surgical inflammatory response.To investigate the treatment efficacy of arthroscopic anterior cruciate ligament reconstruction (AACLR) combined with sodium hyaluronate (SH) in ACLI patients with and without KOA.This prospective cohort study included 226 ACLI patients with or without KOA who were admitted between July 2015 and December 2018 into The Second Xiangya Hospital, Changsha, China. All patients received AACLR surgery combined with 50 mg SH. Serum levels of inflammatory markers were evaluated with enzyme-linked immunosorbent assay (ELISA), and knees were assessed using the Lysholm Knee Score and the International Knee Documentation Committee Knee Evaluation Form (IKDC). The range of motion of the knee joint was also measured.The mean disease course was 73.39 ±30.90 months for ACLI patients with KOA, which was significantly longer than for those without KOA (3.74 ±1.70 months). Also, surgery duration was remarkably longer for patients with KOA than it was for those without this disease. The Lysholm Knee Score and IKDC score, as well as the range of knee joint motion were significantly improved in all patients after treatment compared to baseline. However, no significant differences were found between the groups. One day, 3 days and 7 days after surgery, significantly higher inflammatory marker levels were found in the patients with KOA than in those without KOA.The AACLR combined with SH was efficacious as it improved knee function and inflammation in all patients, while patients without KOA exhibited a more rapid recovery from the post-surgical inflammatory response.

Current research in broken rotor bar (BRB) fault detection in induction motors is primarily focused on a high-frequency resolution analysis of the stator current. Compared with a discrete Fourier transformation, the parametric spectrum estimation technique has a higher frequency accuracy and resolution. However, the existing detection methods based on parametric spectrum estimation cannot realize online detection, owing to the large computational cost. To improve the efficiency of BRB fault detection, a new detection method based on the min-norm algorithm and least square estimation is proposed in this paper. First, the stator current is filtered using a band-pass filter and divided into short overlapped data windows. The min-norm algorithm is then applied to determine the frequencies of the fundamental and fault characteristic components with each overlapped data window. Next, based on the frequency values obtained, a model of the fault current signal is constructed. Subsequently, a linear least squares problem solved through singular value decomposition is designed to estimate the amplitudes and phases of the related components. Finally, the proposed method is applied to a simulated current and an actual motor, the results of which indicate that, not only parametric spectrum estimation technique.

On the basis of small axial fan with five blades, 6 types of small axial flow fans with different chord lengths splitter blades were designed. Numerical simulation of 6 fan models with splitter blades and prototype fan were done by using Fluent. Based on the obtained simulation results, internal flow characteristics and aerodynamic noise were analyzed and compared. It indicates that: splitter blades with suitable chord length have improved significantly on internal flow characteristics, which inhibits backflow from pressure surface to the suction surface at blade tip and leading edge and restrains flow separation. The 6 model fans are better than prototype fan on aerodynamic noise improvement, but too long or too short chord lengths are both disadvantage to improve aerodynamic noise. The results reveal that 2/6, 3/6 and 4/6 chord length model have relatively better acoustic characteristics and internal flow characteristics. The research program will offer a reference for structural improvements and noise reduction on small axial flow fan.

Compared with single rotor small axial flow fans, dual-rotor small axial flow fans is better regarding the static characteristics. But the aerodynamic noise of dual-rotor small axial flow fans is worse than that of single rotor small axial flow fans. In order to improve aerodynamic noise of dual-rotor small axial flow fans, the pre-stage blades with different perforation numbers are designed in this research. The RANS equations and the standard k-ɛ turbulence model as well as the FW-H noise model are used to simulate the flow field within the fan. Then, the aerodynamic performance of the fans with different perforation number is compared and analyzed. The results show that: (1) Compared to the prototype fan, the noise of fans with perforation blades is reduced. Additionally, the noise of the fans decreases with the increase of the number of perforations. (2) The vorticity value in the trailing edge of the pre-stage blades of perforated fans is reduced. It is found that the vorticity value in the trailing edge of the pre-stage blades decreases with the increase of the number of perforations. (3) Compared to the prototype fan, the total pressure rising and efficiency of the fans with perforation blades drop slightly.

The unique Coanda surface has a great influence on the performance of bladeless fan. However, there is few studies to explain the relationship between the performance and Coanda surface curvature at present. In order to gain a qualitative understanding of effect of the curvature on the performance of bladeless fan, numerical studies are performed in this paper. Firstly, three-dimensional numerical simulation is done by Fluent software. For the purpose to obtain detailed information of the flow field around the Coanda surface, two-dimensional numerical simulation is also conducted. Five types of Coanda surfaces with different curvature are designed, and the flow behaviour and the performance of them are analyzed and compared with those of the prototype. The analysis indicates that the curvature of Coanda surface is strongly related to blowing performance, It is found that there is an optimal curvature of Coanda surfaces among the studied models. Simulation result shows that there is a special low pressure region. With increasing curvature in Y direction, several low pressure regions gradually enlarged, then begin to merge slowly, and finally form a large area of low pressure. From the analyses of streamlines and velocity angle, it is found that the magnitude of the curvature affects the flow direction and reasonable curvature can induce fluid flow close to the wall. Thus, it leads to that the curvature of the streamlines is consistent with that of Coanda surface. Meanwhile, it also causes the fluid movement towards the most suitable direction. This study will provide useful information to performance improvements of bladeless fans.

We analyze the mechanism of natural resource regulation on regional economic growth and estimate the model based on panel data for 31 Chinese provinces from 2000 to 2009. Our findings suggest that a fixed effect model is more appropriate than a mixed cross section or random effect model. A fixed effect model between natural resource regulation and regional economic growth quantity and quality was constructed to check the validity of natural resource regulation on regional economic growth. We found that natural resource regulation is effective at regulating regional economic growth; and natural resource regulation restrains regional economic speed to some extent. The per unit growth of natural resource regulation intensity will cut 24.6 billion CNY in gross domestic product; however, natural resource regulation can improve the quality of regional economic growth. Growth in the per unit natural resource regulation intensity will increase the index of regional economic growth quality by 0.022 units...

To effectively extract the interturn short circuit fault features of induction motor from stator current signal, a novel feature extraction method based on the bare-bones particle swarm optimization (BBPSO) algorithm and wavelet packet was proposed. First, according to the maximum inner product between the current signal and the cosine basis functions, this method could precisely estimate the waveform parameters of the fundamental component using the powerful global search capability of the BBPSO, which can eliminate the fundamental component and not affect other harmonic components. Then, the harmonic components of residual current signal were decomposed to a series of frequency bands by wavelet packet to extract the interturn circuit fault features of the induction motor. Finally, the results of simulation and laboratory tests demonstrated the effectiveness of the proposed method.

The mineral resources exploitation stage and the economic growth rate are various in different regions of Xinjiang Autonomous region. Using the method of location quotient, this paper identifies and classifies the intensive regions of three types of mineral resources, known as coal, oil and natural gas, respectively. The intensive regions of economic growth were also identified, according to the rate of per capita GDP growth at prefecture, autonomous prefecture and city. The relationships between different mineral resources and economic growth are different, for example, the relationship between economic growth and coal resource is positive, while the relationship between economic growth and oil resource, or natural gas resource is negative. This study empirically examines the effects of natural resources on economic growth of Xinjiang. The results show that whilst natural resources have a positive impact on growth, and can make a negative impact on growth through the transmission channels, such ...

In this paper, an improved pork freshness detecting method based on digital image processing and BP neutral network was presented. The shape of the slaughtering fresh pork cell was oval and smooth and it will change obviously in the process of pork corruption. The edge of cell will rupture and merge together until being absolutely misshapen. Seven characteristic parameters about cell shape would be extracted to stand for the level of corruption. And designs then correspond to the pork freshness standard TVB-N and characteristic parameters finally trained by BP neural network. The experimental results showed that the characteristic parameter about cell shape could detect the freshness effectively.

The static characteristics of dual-rotor small axial flow fans are better than that of single rotor small axial flow fans. While, compared with single rotor small axial flow fans, the noise of dual-rotor small axial flow fans highly increases. Regarding to this reason, the perforation blade are designed for dual-rotor small axial flow fans in this paper. Pre-stage blades, post-stage blades, and both pre-stage and post-stage blades were perforated respectively. The k–e turbulence model and the FW-H noise model were used to simulate. Then, the static characteristics and aerodynamic performance of the prototype fan and the fans with perforation blade were contrasted and analyzed. The results show that: In general, the pressure rising and efficiency of the fans with perforation blade declines slightly. Compared to another two perforation blade, and the pressure rising and efficiency of the fans of pre-stage perforating fan shows the smallest reduction, but increases slightly at the optimum operating condition; With the difference of perforation way, the variation of the noise level are different, while, in the outlet zones, the noise are all reduced;. The centralized region of vorticity in the trailing edge of the blades are reduced, and the noise of the fans are all reduced. All the results show that, using perforation blade can improve the aerodynamic performance of dual-rotor small axial flow fans.Copyright © 2014 by ASME

The effect of 4-hydroxy-6-methyl-1,3,3a,7-tetraazaindenee (TAI) addition on the electric properties (photoelectric lifetime and ion conductivity) of tabular silver halide microcrystals and their sensitometric property has been studied. The result shows that the addition of TAI decreases the ionic conductivity of the tabular silver halide microcrystals and prolongs their photoelectron lifetimes, thus to some extent promoting the sensitivity enhancement of the emulsion. □ 1 Introduction 4-Hydroxy-6-methyl-1,3,3a,7-tetraazaindenee (TAI) has been found to be one of the best photographic stabilizers and has also recently been used as a sensitizer [1]. Much research has been carried out on polydispersed and cubic emulsions [2] to find a photographic application of TAI [3-5], although few investigations have been devoted to AgBr (I) tabular microcrystals and to the correlation between the electric property and sensitometrical performance. It is known that dielectric loss measurement is an effective method for measuring the influence of TAI on ionic conductivity-hence the concentration of interstitial silver ions in emulsion grains. The measurement of microwave photoconductivity can produce information concerning the behaviour of photoelectrons in emulsion grains. In this study, the authors examine the effect of TAI addition on electric properties and hence correlate the electric and sensitometric properties of silver halide emulsion microcrystals.

UPS, XPS, AES and LEED have been applied to the study on the samples prepared by low energy N+ (0.5KeV) sputtering of the clean cleavaged surface of 2H-MoS2(0001). A new "shoulder" of a band tail above the top of the dz2 band shows that the surface is chemically active to O2 at room temperature. The causes for the chemical activeness have been analyzed.

Work function and photoemission spectroscopy have been applied to the study of the interaction of Co overlayers with the ion sputtered basal face of MoS2(0001). The experimental results show that upon Co deposition the work function of the MoS2 substrate drops rapidly and reaches a minimum value of -0.65eV for Δ, and then increases to the metal Co work function at coverages greater than a monolayer. The Fermi level pinning at 2.2eV above the Mo 4dz2 peak has been found at a low submonolayer coverage.

To elucidate the promotion action of cobalt on Mo sulfide catalysts, UV-Photoelectron Spectroscopy (UPS), x-ray Photoelectron Spectroscopy (XPS) and Low Energy Diffraction (LEED) have been applied to study the submonolayer deposited process of metal Co on the highly edged surfaces of MoS2 crystal. The results show that the electronic effect near EF rather than the chemical changes on the surfaces, might be primary influence.

To elucidate the promotion action of cobalt on Mo sulfide catalysts, UPS, XPS and LEED have been applied to study the submonolayer deposite process of promotor metal Co on the active catalytic phase for Co-Mo catalyst-the highly edged surfaces and ion sputtered basal plane of MoS2 crystal. At a certain submonolayer coverage of deposited Co, the new Co-correlated interface states could raise surface EF to a new higher pinning position by about 0.30-0.35eV. So the surface barrier and work function for these catalytic active phases are decreased. The remarkable changes for electronic structure near EF and the studies of LEED patterns reveal that the active phase Co-Mo-S, in which the Co-Mo bond appears to behave in much the same way as in the intermetallic bond, could be formed by locating the promotor Co at the surface disorder defects in edge sites.

The submonolayer depositions of the promoter metals Ni and Fe on the low energy ion (N+ ions below 1 keV) preferentially sputtered basal faces of a MoS2 single crystal have been studied by ultraviolet photoemission spectroscopy (UPS), X-ray photoemission spectroscopy (XPS) and low energy electron diffraction (LEED). The experimental results show that for increasing metal coverages the MoS2 valence band (VB) centroids move towards larger binding energies about 0.3–0.4 eV (relative to EF) and the core-level binding energies (BE) of these Group VIII metals decrease. These results and the variation of the electronic density of states near EF are related to their electronic properties.