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The increased social and economic burdens make osteoporosis in men an emerging public health issue. However, the quality of life among men with osteoporosis is still unclear. This systematic review and meta-analysis aimed to evaluate the health-related quality of life (HRQoL) among men with osteoporosis or osteoporotic fracture. PubMed, EMBASE, and the Cochrane Library database were systematically searched from inception to May 2021. Studies were included if they used validated questionnaires to measure HRQoL among osteoporotic men. A meta-analysis was performed using a random-effects model or fixed-effects model to calculate the standard mean difference (SMD) or mean difference (MD) with 95% confidential interval (95% CI). 14 studies involving 6338 male participants were chosen for systematic review, of which 10 were included in the meta-analysis. Men with osteoporosis had poorer global HRQoL and multiple dimensions of HRQoL than men without osteoporosis. Hip fracture, vertebral fractures, or wrist fractures dramatically impaired HRQoL of men, and physical function was declined even before hip fracture (SMD = −0.60, 95% CI, −0.82 to −0.39). Femoral and lumbar BMD was positively correlated with HRQoL, and a number of fragility fractures and time since fracture had negative effects on HRQoL. Effective anti-osteoporotic drugs could improve HRQoL of men. The health-related life quality of men was significantly impaired by osteoporosis and fracture of the hip, vertebral, or wrist. We should pay more attention to the diagnosis and treatment of male osteoporosis to improve the life quality of men.

Motivated by the problem of radar target recognition, we develop a label-aided factor analysis (LA-FA) model for statistical modeling of high-resolution range profile (HRRP) under the prerequisite that the HRRP data are Gaussian distributed. The LA-FA model is the extension of the multitask learning-based factor analysis (MTL-FA) model, which is mainly applied to the recognition problem with small training data size. Compared to the MTL-FA model, our LA-FA model introduces the discrete class labels via Sigmoid-Bernoulli hierarchy to restrict the learning of model parameters, which offers the potential to enhance the separability of statistical models from different classes, thus beneficial to the improvement of recognition capability. In addition, since the noise level of a test sample is usually different from those of the training samples in the real application, we introduce a noise-robust modification method for Gaussian-based models. The proposed modification method is implemented by updating the noise level parameter of the statistical model according to the estimated signal-to-noise ratio (SNR) of test HRRP. Experiments on measured HRRP data demonstrate the better recognition performance of the LA-FA model with limited training data and our noise-robust model modification method under low test SNR. Especially, when there are 20 training HRRP samples per frame, the recognition rate of our LA-FA model is 7% higher than that of the MTL-FA model, and moreover, the recognition accuracy of the noise-robust LA-FA model is 3% higher than that of the LA-FA model without modification under the condition of SNR = 15 dB.

Passive reconstruction methods such as traditional multi-view stereo are capable to accurate reconstruction results. However, the depth calculation of multi-view stereo encounters significant difficulties, especially when the corresponding points have some degree of inaccuracy or unreliability. In this paper, we make use of geometric and shading cues information in the multi-view stereo approach to construct a robust energy function, which is also effective to optimize the depth information provided by multi-view stereo. This work improves the accuracy of point cloud depth. we evaluated our algorithm in the famous DTU datasets, and established our own dinosaur datasets. All the data is collected by mobile devices under natural light condition, while the reconstruction results are completed and accurate.

薄膜晶体管液晶显示器（TFT-LCD）扭曲向列型（TN）液晶曲面显示器搭配宽视角偏光片暗态时会发生色不均现象，推测色不均现象的发生机理为：曲面状态时，玻璃基板受应力发生形变，面板中应力不均，加之液晶双折射，暗态时上视角观察显示屏上下两侧边缘发蓝。本文模拟了不同改善措施对色不均现象的影响，同时对有改善的模拟结果进行了实验测试。测试结果表明，可以通过两种方式改善色不均现象：第一种是增加暗态亮度，掩盖暗态时色不均现象，如调整电路、偏光片吸收轴角度等。实验结果表明调整电路使显示器暗态亮度从0.18 cd/m2提升至0.25 cd/m2，色不均面积由显示器面积的30%减小至10%，吸收轴角度从135°调整至134.5°，色不均面积减小至10%，但电路调整使显示器响应时间增加2.5倍，吸收轴角度调整0.5°会使对比度下降20%，对产品性能均有不利影响；第二种是改善曲面状态下显示屏内部应力均一性，如增加液晶盒盒厚、高温老化、降低显示器玻璃基板厚度等。实验结果表明：降低玻璃厚度至0.2 mm以及高温60℃老化72 h均能使色不均现象消失，且对产品性能无不利影响。

Based on the consideration of complementary advantages, different wavelet, fractal and statistical methods are integrated to complete the classification feature extraction of time series. Combined with the advantage of process neural networks that processing time-varying information, we propose a fusion classifier with process neural network oriented time series. Be taking advantage of the multi-fractal processing nonlinear feature of time series data classification, the strong adaptability of the wavelet technique for time series data and the effect of statistical features on the classification of time series data, we can achieve the classification feature extraction of time series. Additionally, using time-varying input characteristics of process neural networks, the pattern matching of timevarying input information and space-time aggregation operation is realized. The feature extraction of time series with the above three methods is fused to the distance calculation between time-varying inputs and cluster space in process neural networks. We provide the process neural network fusion to the learning algorithm and optimize the calculation process of the time series classifier. Finally, we report the performance of our classification method using Synthetic Control Charts data from the UCI dataset and illustrate the advantage and validity of the proposed method.

My country is the largest installed hydropower capacity in the world, the safe, stable, and reliable operation of the unit has always been a technical problem faced by the hydropower industry. The runner is the core part of the hydropower unit for energy conversion, and its quality will directly affect the reliability and hydraulic performance of the unit. At present, the detection of the runner status of the running unit is completely manual. To solve the problems of low efficiency, high cost, and great harm to the human body of Large Francis turbine runner blades, a new type of defect detection robot for turbine runner blades was designed. The robot body structure is designed by modules, which is easy to load and unload, easy to carry, fast manufacturing, and low requirement for manual operation. Magnetic adsorption chain track is introduced into the wheel system of the robot, and two groups of tracks are adopted, which makes the robot compact and can move flexibly in the narrow space turbine runner. On the other hand, the central position of the robot is equipped with an adsorption force self-adjusting device to ensure that the robot can stably adsorb on the blade surface at a certain angle from the horizontal plane.

Modular construction methods are adopted in many spatial and temporal limited projects. As the major equipment used in modular construction, the mobile crane affects the safety and efficiency of construction significantly. Currently, building information modeling (BIM) is widely adopted to improve the lifting operation planning of cranes. However, the inaccurate simulation of the dynamic construction environment makes those BIM-based lifting operation planning methods unsuitable for land mobile cranes operation planning, such as in the overpass bridge construction project, which may cause several safety risks during the lifting process. Based on an overpass steel bridge construction project, this paper attempted to integrate the BIM and unmanned aerial vehicles (UAVs) to streamline lifting operation planning and construction monitoring. Specifically, in the preliminary stage, a level of development (LOD) 400 steel superstructure model was built and then divided into eighty sections. In addition, a three-dimensional (3D) geology model of the as-is construction site was modeled by UAV-captured images. Then, a fusion model which contains the lifting modules models, the as-is site model, and the crane model was gathered, based on which the collision detection was conducted by 4D crane operating path simulation. According to the results, three potential collisions were found and eliminated by lengthening the jib of the crane from 43.5 m to 46.5 m. Furthermore, the optimum crane location for lifting each steel structure was determined based on the 3D geology model. The study shows that the UAV is able to acquire geological information and then 3D simulates the real construction environment quickly and accurately. Furthermore, BIM and UAV have the potential to optimize the design and construction as well as the monitoring of bridge projects.

Objective: Detection of SARS-CoV-2 by oropharyngeal swabs (OPS) and nasopharyngeal swabs (NPS) is an essential method for coronavirus disease 2019 (COVID-19) management. It is not clear how detection rate, sensitivity, and the risk of exposure for medical providers differ in two sampling methods.Methods: In this prospective study, 120 paired NPS and OPS specimens were collected from 120 inpatients with confirmed COVID-19. SARS-CoV-2 nucleic acid in swabs were detected by real-time RT-PCR. The SARS-CoV-2 detection rate, sensitivity, and viral load were analyzed with regards NPS and OPS. Sampling discomfort reported by patients was evaluated.Results: The SARS-CoV-2 detection rate was significantly higher for NPS [46.7% (56/120)] than OPS [10.0% (12/120)] (P < 0.001). The sensitivity of NPS was also significantly higher than that of OPS (P < 0.001). At the time of sampling, the time of detectable SARS-CoV-2 had a longer median duration (25.0 vs. 20.5 days, respectively) and a longer maximum duration (41 vs. 39 days, respectively) in NPS than OPS. The mean cycle threshold (Ct) value of NPS (37.8, 95% CI: 37.0–38.6) was significantly lower than that of OPS (39.4, 95% CI: 38.9–39.8) by 1.6 (95% CI 1.0–2.2, P < 0.001), indicating that the SARS-CoV-2 load was significantly higher in NPS specimens than OPS. Patient discomfort was low in both sampling methods. During NPS sampling, patients were significantly less likely to have nausea and vomit.Conclusions: NPS had significantly higher SARS-CoV-2 detection rate, sensitivity, and viral load than OPS. NPS could reduce droplets production during swabs. NPS should be recommended for diagnosing COVID-19 and monitoring SARS-CoV-2 load.Chinese Clinical Trial Registry, number: ChiCTR2000029883.

With the application of image more and more widely, People put forward higher requirements on the image quality of small objects and details in the image. In recent years, with the development of deep learning, it achieved good results in the research of image super-resolution. In this paper, we proposed EDSRGAN, a single image super-resolution(SISR) algorithm, based on enhanced residual network and the adversarial network. Compared with SRGAN, which is also based on the adversarial network, EDSRGAN can greatly reduce the high-frequency noise contained in the super-resolution(SR) image, and it also leads SRGAN in terms of peak signal to noise ratio and structural similarity evaluation indicators. Although EDSRGAN lagged behind EDSR in terms of peak signal to noise ratio and structural similarity, the SR images generated by EDSRGAN were sharper than EDSR in the object edges and targets details. EDSRGAN could achieve good results in image super-resolution on small targets.

This paper expounds fault intelligent diagnosis system of based on fuzzy inference and knowledge base, and we use it in fault diagnosis of a communication equipment. Introduce the overall frame of the fault diagnosis expert system for the communication equipment, and explain the functions and the tactics of every part. And then propose the methods, with which the knowledge is acquired based on expert system. The system adopts a kind of new inference mechanism, which combines the fuzzy inference with the rule inference, and makes good use of the advantages of the two methods.

We have evaluated the total-ionizing-dose response of graphene-based X-ray detectors fabricated from graphene oxide (GO) via laser scribing. Raman characterization shows that the resulting structures exhibit the desired conversion of GO to graphene; both high- and low-resistance detectors are formed. The detectors are quite radiation sensitive, as demonstrated by fast pulse testing. The response time of the detectors degrades with total-ionizing dose exposure as a result of electron trapping at residual oxygen from unreacted GO and/or adsorbed oxygen on the graphene surface.

Hyperspectral image (HSI) super-resolution has gained great attention in remote sensing, due to its effectiveness in enhancing the spatial information of the HSI while preserving the high spectral discriminative ability, without modifying the imagery hardware. In this paper, we proposed a novel HSI super-resolution method via a gradient-guided residual dense network (G-RDN), in which the spatial gradient is exploited to guide the super-resolution process. Specifically, there are three modules in the super-resolving process. Firstly, the spatial mapping between the low-resolution HSI and the desired high-resolution HSI is learned via a residual dense network. The residual dense network is used to fully exploit the hierarchical features learned from all the convolutional layers. Meanwhile, the gradient detail is extracted via a residual network (ResNet), which is further utilized to guide the super-resolution process. Finally, an empirical weight is set between the fully obtained global hierarchical features and the gradient details. Experimental results and the data analysis on three benchmark datasets with different scaling factors demonstrated that our proposed G-RDN achieved favorable performance.

Distributed generation has gradually become an important part of energy power supply system in China. The development situation early warning of distributed generation is helpful to guide the healthy and orderly development of distributed generation. This paper proposes a development situation early warning method of distributed generation. The distributed photovoltaic power situation early warning index system is established, which contain developmental level, rate of capacity utilization, project profitability, the grid adequacy and the layout coordination. Based on distributed photovoltaic development data of recent five years, short-term forecast and comprehensive evaluation of distributed photovoltaic development situation are made. Case study shows that this method can provide a more scientific and comprehensive development situation early warning of distributed generation, and provide support for targeted policy suggestions.

Island is an important part of sea system. The construction of a reservoir to avoid salt water and store fresh water could help to solve the problem of scarce freshwater resources in the development of island. Located in the Yangtze Estuary, Chongming Island is the third largest one in China. The water supply mode has been transformed from the decentralized water supply to centralized water supply since the completion of Dongfenxisha Reservoir in 2014. The spilling over saltwater is a major threat to the safety of Dongfengxisha water source under natural conditions. Considering the effect of the northerly wind, a two-dimensional tidal-salinity mathematical model of the Yangtze Estuary is established to study the relationship between the salinity and the runoff process of the water intake in Dongfengxisha Reservoir. The salt water around the Dongfengxisha Reservoir is mainly spilled over from the North Branch. Saline water intrusion in the Yangtze Estuary is the most severe in January, with the maximum salinity of 2.31‰. Because of its short duration, the water sources safety can be guaranteed. Building a tidal gate in the North Branch is an effective way to improve the safety of Dongfengxisha Water Source and only closing it in the spring tide would already achieve a good results. If there are serious adverse factors for saline intrusion, such as small runoff and sustained northerly wind, the safety of water sources could also be ensured by prolonging the closing time. This research can also provide reference for the construction of water sources in other islands.

Objective The purpose of this study was to determine the clinical characteristics and biomarkers in patients with coronary microvascular dysfunction (CMVD) and to compare them with patients with obstructive coronary artery disease (OCAD). Methods We conducted a single-center, hospital-based, observational, descriptive, comparative, clinical study of 40 patients, including 20 patients with CMVD and 20 with OCAD. We assessed laboratory biomarkers (low-density lipoprotein [LDL], high-density lipoprotein [HDL], red blood cell distribution width [RDW], brain natriuretic protein [BNP], troponin I), and PET/CT coronary flow reserve was performed. Results The mean coronary flow reserve (CFR) in patients with CMVD was 1.96±0.55. Mean low-density lipoprotein cholesterol (LDL-C) levels were significantly higher in the CMVD subgroup (2.53±0.63 mmol/L) compared with the OCAD subgroup (1.76±0.97 mmol/L). Logistic regression analysis identified LDL-C as a predictor for the development of CMVD (odds ratio, 5.24). Conclusion It is difficult to differentiate between OCAD and CMVD based on the patient’s medical history, clinical characteristics, and coronary angiography results. Further investigations may be needed to allow an accurate diagnosis. CFR measurements based on non-invasive positron emission tomography/computed tomography may aid the diagnosis of CMVD. We also identified LDL-C as a predictor for the development of CMVD.

This paper presents a method to evaluate operational risks of distributed generation integrating to power grid enterprises. By using the data of total power consumption and average unit capacity cost, macro-level evaluation for risks of power grid revamping cost increase, power purchase cost increase, power sales market share reduction, sunk cost increase and line grid loss increase is made. A case study of distributed PV in Jiangsu province is carried out.

The calculation method of stability derivative which is based on CFD is employed to simulate the forced sinusoidal oscillating motion of low-aspect-ratio flying wing theory configuration and wind tunnel experiment configuration around body axis. Pitch\yaw\roll dynamic derivatives can be obtained with parameter identification technology from the time history of unsteady aerodynamic force and moment coefficient. The sting interference of static fluid characteristics and dynamic derivatives for low-aspect-ratio flying wing in transonic is studied quantitatively. The conclusions are: 1. The sting interference of pitch damping with angle of attack remain almost 5%–9%, except a rapid decrease to 2% at α = 15°; 2. The amount of interference of yaw damping is extremely large at small angle of attack (yaw damping of experimental model is almost a great many times of theory model), the amount of sting interference maintains in 10%–50% when the angle of attack is at α = 20°–25°; 3. The sting interference of roll damping maintain in 1%–2% at α = 0°–15°, and as the angle of attack increases, the interference rises gradually until 6% at α = 25°. The research can provide conference for the correction of sting interference of wind tunnel experiments for dynamic derivatives.

Symmetrical aerospace configuration design has greatly increased currently. Compare with conventional aerospace vehicles, those aerospace vehicles’ aerodynamic forces have the characteristics of strong unsteady, nonlinear and longitudinal/directional/lateral coupling. To study those characteristics, accurate prediction and accurate measurement the dynamic stability derivatives of the vehicles is strongly needed. One important tool is dynamic derivative wind tunnel test. With these issues in method, the difficulties of dynamic derivative wind tunnel test in hypersonic wind tunnel will be solved, and a forced oscillation test rig for measure dynamic derivative of hypersonic vehicle will be built here. The test rig has been completed with a symmetrical hypersonic aerospace model under Mach number 5.0 to 8.0, and the direct dynamic derivative and coupling dynamic derivative has been obtained. The test result shows that: comparing the direct dynamic derivative results of forced oscillation test with free oscillation test, the relative deviation is less than 10%. The new test technique can meet the requirement of the dynamic derivative test of hypersonic vehicles.

The action of the opposition is conveyed on a fundamental level. Moreover, it finds image detection related information on contenders and football sports Image, which can be realized in the outside image. From the force situation, one can see that image advancement is up. Therefore, this assessment development image as a thing to ponder the usage of image acknowledgment development. Football sports detection is dealing with the whole system. The structure configuration relies upon hardware, including a Field Programmable Gate Array (FPGA). This new computation particle swarm algorithm estimation is implemented to edge recognizable proof, grayscale planning, object get, target affirmation, image area development, etc., which are consolidated into the genuine need of the game video to achieve the various essentials of development image acknowledgment. All the while, it has set itself up as a demonstrating ground to test the suitability of the investigation framework that sees the affirmation of contenders, games affirmation, sports lead judgment, etc. Football sports Image detection results of the relevant investigations have revealed that the existence of the solution.

Cables are the main load-bearing components of cable-stayed Bridges. The durability and reliability of cables are directly related to the safe operation and service life of the whole bridge. Aiming at the problem of cable detection and maintenance, a new type of cable detection robot is designed in this paper. To further enhance the stability of the robot, the structure adopts symmetrical arrangement to make the center of mass of the robot system coincide with the cable axis. According to the working condition of the robot, a flexible body spring that meets the parameter requirements is designed, which not only meets the required preload, but also meets the starting torque of the motor. The robot is simple in structure, standardized in parts, easy to assemble and disassemble, and has good obstacle clearance ability and detection efficiency.

At low bit rates, visually annoying blocking artifacts are usually introduced in JPEG compressed images. In this paper, we proposed an image deblocking method combined with the shape-adaptive low-rank (SALR) prior, the quantization constraint (QC) prior and sparsity-based detail enhancement. We firstly design a deblocking model to obtain initial deblocked images under the maximum a posteriori (MAP) framework. More specifically, with the assumption of Gaussian quantization noise, the SALR prior is utilized to effectively separate signal from noise and preserve image edges. Compared with previous low rank priors, the SALR reconstructs a better result via shape adaptive blocks. The QC prior is also adopted to avoid over-smoothing and to enable a more accurate estimation. Finally, by extracting features of external images, the mapping matrix of sparse dictionary pairs is trained to enhance image details. Extensive experimental results demonstrate that the proposed deblocking method has superior performances in both subjective vision and objective quality.

This paper reveals a novel saturated iron-core fault current limiter (SICFCL). The novel SICFCL use tightly coupled structure of AC and DC windings to overcome the shortcomings of the traditional loosely coupled structure and to increase the flux transfer efficiency and improve the ratio of current limiting impedance to steady state impedance; Use the cross-parallel structure of four AC windings to eliminate the AC magnetic flux in the DC winding and prevents the AC induction voltage on the DC winding from damaging the DC components. This paper analyzes the working principle and impedance characteristic curve of novel SICFCL and establishes a simulation model of the novel SICFCL based on ANSYS finite element simulation software. The influence of novel SICFCL connected to power grid is analyzed in a typical 10kV application scenario, including the current changes in all kinds of short-circuit fault and the requirement of grid reclosing. The simulation results verify the correctness of the novel SICFCL and provide guidance for the development of the device and connected to actual power grid.

The associations of the risk of lung cancer with the vitamin D intake and serum level are controversial. We performed a comprehensive dose-response meta-analysis to evaluate the precise relationships between the above mentioned parameters. We performed a web search of the PubMed, Medline, and Embase databases to identify potential studies that evaluated the relationships between vitamin D intake or serum 25-hydroxyvitamin D (25([OH]D) levels and the risk of lung cancer on December 5, 2017. According to the inclusion and exclusive criteria, 16 studies were included in this meta-analysis. The pooled relative risks (RRs) with 95% confidence intervals (CIs) were used to assess the strength of the associations. A dose-response analysis was conducted to quantitate the relationship between the serum 25(OH)D or vitamin D intake and the risk of lung cancer. The pooled RR (highest level vs lowest level) showed that the serum 25(OH)D level was not associated with the risk of lung cancer (RR = 1.046, 95% CI = 0.945–1.159). A high vitamin D intake was inversely correlated with the lung cancer risk (RR = 0.854, 95% CI = 0.741–0.984). No significant dose-response relationship was observed between the serum 25(OH)D level and the lung cancer risk. The linearity model of the dose-response analysis indicated that with every 100 IU/day increase in vitamin D intake, the risk of lung cancer decreased by 2.4% (RR = 0.976, 95% CI = 0.957–0.995, P = .018). A high vitamin D intake provides limited protection against lung cancer carcinogenesis.

Recoil-proton track imaging (RPTI) is an attractive technique to optically record the tracks of recoil protons in scintillation gas by using realtime imaging devices. For the first time, its use as an online nuclear track detector for neutron spectrometry measurements (NSM) is explored. Based on the RPTI methodology for NSM, a very basic detector system is designed, consisting of the neutron-to-proton recoil system and proton track imaging system. Satisfactory performance of the RPTI neutron spectrometer has been examined with a series of Monte Carlo simulations. Moreover, using well-defined line-proton sources from a tandem accelerator, the capability of the detector for imaging proton tracks at the single-particle level in real time has been validated in preliminary experiments. From the clear single proton tracks in the images, the proton ranges were easily distinguished, and precise proton energy spectra were unfolded, laying a solid experimental foundation for the future implementation of NSM.

A ZnO:Ga single crystal with an applicable size of φ40 × 1 mm was prepared using the hydro-thermal method. The crystal exhibits good crystallinity and scintillation properties with a 63.94-arcsec full-width at half-maximum (FWHM) in the X-ray rocking curve (XRC) spectrum, 8% luminous non-uniformity, emission at 389 nm in the X-ray excited luminescence spectrum, fast response and 5.5% BGO luminous intensity. Furthermore, an X-ray pinhole imaging system of nanosecond temporal resolution with a ZnO:Ga single-crystal image converter was established to diagnose the cathode electron emission spatial distribution of an intense current diode. Results for shutter times of 4 μs and 5 ns were obtained, which directly represent the cathode electron spatial distribution throughout the entire pulse duration and during a certain moment of the pulse, respectively. The results demonstrate that the large ZnO:Ga single crystal can diagnose the spatial distribution of cathode electron emission in an intense current diode with high temporal resolution and provide new solutions for high-temporal-resolution diagnosis of a pulse radiation field.

Plastic scintillators are extensively used in various radiation measurement systems. However the total internal reflection decreases the scintillation light output, leading to a low detection efficiency especially in these weak signal detection situations. In the present investigation, we have designed a light extraction scheme based on the photonic crystal formed with a monolayer periodic array of polystyrene nanospheres by a self-assembly method. The photonic crystal coated on the surface of plastic scintillator can significantly enhance the light extraction by 120% compared with the plain reference sample under X-ray excitation, which is achieved by the principle of the coupling of evanescent field near the scintillator-air interface with the photonic crystal.

The present-day unconventional and high-lifting aerospace configuration design has greatly increased the demand for accurate prediction and expanded measure dynamic stability derivatives envelopes of conventional aerospace vehicles. With these issues in mind, china academy of aerospace aerodynamics (CAAA) designed and built a forced oscillation test rig in the sub-, tran- and supersonic wind tunnel that provides new capabilities for aerodynamic researchers to accurately measure the dynamic derivatives and investigate the asymmetric coupling effects of high-lifting aerospace configuration vehicles.

The capability of existing MV metal enclosed switchgear is restrained by its poor short circuit making performance of earthing switch. A new type of direct acting earthing switch with rated voltage 12kV is designed for better short circuit making capability in this paper. A series of different springs which supply different forces and different main circuit arrangement patterns which produce different electro-dynamic forces are manufactured in order to supply different closing speeds. Therefore corresponding experiment switch peak current of 80kA are performed to study the relationship between closing speed and making capability. The results of experiments show that the capability of short circuit making increases with the rising of closing speed and the electrical durability of the earthing switch is at least 8 times when the max measuring closing speed is 3.82 m/s especially. The research on direct acting earthing switch in this paper is meaningful for large capacity MV metal enclosed switchgear.

A novel neutron diagnostic method is presented based on optical readout from scintillation in gases excited by recoil charged particles for fusion research. According to the method, we have designed a new gas scintillation chamber filled with scintillation gas CF4 and installed with a multi-wires structure to provide strong electric field. The electric field distributions of cylindrical multi-wire structures with different geometrical parameters are analyzed systematically. By building up an optimal multi-wire structure, the optical readout characteristics are also studied with energetic charged particles. Electron-induced avalanche in the electric field excites gas molecules to emit numerous scintillation photons, which are readout using photomultiplier tubes, and measured using multichannel analysers. The results show that the light signals and charge signals are enhanced simultaneously and the rise time of the light signal hardly changes, approximately 12ns, as the applied voltage increases. More importantly, the typical pulse height spectrum from the light signals is acquired, and the obtained resolution is 8.8% for 6.5MeV protons.

We have investigated the fluorescence decay time of ZnO:Ga scintillator under the excitation of different type charged particles, namely β (0–1.173 MeV), α (5.48 MeV), H+ (15 MeV), Li+ (42 MeV) and O8+ (100 MeV) ions. A strong dependence of decay time on the rate of energy loss dE/dx can be observed. Simulation result shows that the instantaneous non-equilibrium carriers induced by charged particles significantly decrease the local refractive index of semiconductor, which consequently gives rise to a slower decay time for a larger value of dE/dx. The present result has an entire different physical mechanism from the traditional organic and inorganic scintillators such as CsI:Na. This finding could be applied in pulse shape discrimination measurement in a mixed transient radiation field.

Using steel strips to strengthen the existing unreinforced masonry walls has competitive advantages, which includes no wet work, avoidance of formwork, time saving, ease of installation, minimal increase of dimensions, no requirement for material strength of the existing walls and good reversibility. In this paper, seven specimens were fabricated and tested under axial loads for obtaining the effect of pre-stress in steel strips to strengthen unreinforced brick masonry walls. Test results showed pre-compression stress in the vertical steel strips could increase the load of cracks in the single brick in the wall, otherwise steel strips only improved the load of continuous cracks and the failure load, and the axial stiffness of the wall; when the transverse steel strips were pre-tensioned, it could further improve the failure load and the later axial stiffness of the strengthened wall.

Distributed Luby Transform (DLT) codes have been proposed to improve the robustness and system throughputs for multi-source single-sink networks by exploiting the benefits of Network Coding (NC) at a single relay. All the proposed schemes such as the DLT and Soliton-Like Rateless Coding (SLRC) have attempted to maintain Robust Soliton Distribution (RSD) or Soliton-Like Distribution (SLD) for the output data at the relay. This result in some source symbols to be discarded, thereby degrading the throughput. In this paper, we have proposed a novel method called the Full DLT (FDLT) coding scheme to be applied in the InterPlaNetary (IPN) Internet scenario comprising two sources and one relay. The aim of the proposed scheme is to fully utilise the source symbols so as to reduce the overheads and improve energy efficiencies at the sources while maintaining low overhead at the relay. In addition, almost no buffer is needed in the proposed scheme so the relay can have limited storage space, and the proposed scheme is resilient to the churn rates of the nodes. The simulation results have shown that the proposed scheme outperforms the aforementioned schemes with respect to source overheads and total overhead in addition to preserving the benefits of NC and LT codes.

The concept of ecological security stems from environmental security theory, and is generally used to evaluate the ecological security of land, water resources and the city. This study applies the Pressure-Station-Response (P-S-R) model and theory of ecological security with field research in 2010 to establish an index system for tourism ecological security evaluation. The findings show that tourism ecological security in Wuhan has increasingly improved from a comprehensive evaluation value of 5.8023 in 2004 to 6.459 in 2010, and has moved from a “sensitive” condition to “safe” condition. Ecological pressure and ecological response are negatively correlated, and the value of ecological response was below that of ecological pressure during the seven years. In order to make clear the impact factors affecting tourism ecological security in Wuhan, this paper summarizes ten limiting factors influencing tourism ecological security and makes several recommendations to improve tourism ecological security.

The equipment has a high and strict requirement of dynamic seals, especially working with Long stroke reciprocating motion under a sandy condition and with a great deal of gas. The seal form of power cylinder on the underground part of hydraulic power rodless type oil extraction equipment is studied. We design three seal structures, do the performance testing and the life testing with related equipment. It turned out that the seal form that combines gap seal with sand prevention techniques has high performance, longer life. The power cylinder works stably and reliably.

In order to utilize the phase information to improve radar target recognition performance of high range resolution (HRR) target signals, this paper takes adaptive Gaussian classifier (AGC) model and factor analysis (FA) model for instance to generalize Gaussian statistical models to complex domain to build complex HRR models. It is demonstrated that the structures and parameter estimators of complex Gaussian statistical models are invariant to the initial phases of HRR complex data. Furthermore, to enhance the recognition performance under low signal-to-noise ratio (SNR) conditions, a noise-robust modification algorithm is introduced. It solves the mismatch between complex Gaussian models and noisy test signals. Experimental results show that the proposed models can obtain higher average correct recognition rates by utilizing the phase information. Also, the modified models can deal well with noisy test signals.

Steel plate-masonry composite structure is a newly-developed type of structural technique applicable to existing masonry buildings by which the load-bearing walls can be removed for large spaces. This kind of structure has been used in practice for its several advantages, but experimental investigation on its elements is nearly unavailable in existing literature. This paper presents an experimental study on the flexural behaviour of four steel plate-masonry composite beams loaded by four-point bending. Test results indicate that failure of the tested beams always starts from the local buckling of steel plate, and that the tested beams can satisfy the requirement of service limit state. In addition, the assumption of plane section is still remained for steel plate prior to local buckling or steel yielding. By comparative analyses, it was also verified that the working performance of the beam is influenced by the cross-section of steel plate, which can be efficiently enhanced by epoxy adhesive rather than cement mortar or nothing at all. Besides, it was also found that the contribution of the encased masonry to the flexural capacity of the composite beam cannot be ignored when the beam is injected with epoxy adhesive.

Statins, 3-hydroxy-3-methylglutaryl-coenzyme A reductase inhibitors, have been used as a cholesterol-lowering drug to treat hyperlipidemia clinically. In recent years, accumulating evidence indicates the possible beneficial effect of statins on osteoporosis. The aim of present study was to investigate whether protection against osteoporosis by statins is linked to a reduction of oxidative stress and restoration of nitric oxide (NO) formation in aged and ovariectomized rats. The aged and ovariectomized rats were used as two models of osteoporosis for evaluation of the effect of simvastatin. It was found that simvastatin abated oxidative stress, increased NO production, subsequently attenuating osteoporosis in two models. In the in vitro studies, the protective effects against H(2)O(2)-induced cell injury were examined in the MG-63 human osteoblastic cells. It was found that simvastatin ameliorated H(2)O(2)-induced cell loss and cell apoptosis and increased alkaline phosphatase (ALP) activity in osteoblastic cells. Simvastatin abated oxidative stress through enhancing catalase, heme oxygenase 1 (HO-1), and superoxide dismutase (SOD) activity and suppressing NADPH oxidase activity. In addition, simvastatin raised nitric oxide synthase (NOS) activity and eNOS expression at basal condition; inhibited NOS activity and iNOS expression when treated with H(2)O(2). In conclusion, protection against osteoporosis by statins is linked to a reduction of oxidative stress and restoration of NO formation in aged and ovariectomized rats.

The side-flow pump is presented for increasing the setting depth of sucker rod pumping system, which adopts a special structure of side-flow valve, ladder-type solid plunger and breathing hole. By transferring the load of liquid column to the tubing on the upstroke, the new pump achieves a smaller polished rod load. On the basis of in-depth study of the pump, this paper provides a brief formula of the static polished rod load. Assuming the tubing is anchored, a new one-dimensional vibration model of sucker rod pumping system is built, which takes into account the structure of the side-flow pump. Then a mathematical model is used to design the sucker rod pumping system of Well TKN-1, with a setting depth of 4716 m. The results of dynamometer analysis show that mathematical model of side-flow pumping system and its computer programs can successfully model deep rod string performance. The rod pumping system of Well TKN-1 has operated trouble-free for 8 months. The knowledge gained gives confidence for additional future applications.

A total of 32 circular-section concrete columns confined by CFRP sheet were tested in uniaxial compression involved in different preload ratio, concrete strength and CFRP plies. The failure characteristic and mechanics behavior of confined concrete columns were presented, and the descending of the peak stress and strain of confined concrete due to preload were analyzed. The experimental results indicated that the confinement effect of CFRP was influenced by preload ratio observably. The second stiffness, the peak stress and strain declined with preload ratio ascending, and the extent developed with the enhancement of CFRP ply.

The steel-plate-masonry composite structure is an innovative type of structural scheme popular in masonry structures with load-bearing walls removed for a large space. A total of 4 column specimens under static loading were tested to mainly study the failure modes, load-carrying capacity, and strain distribution in the critical cross-section. Results show that the composite columns started an initial failure from local buckling of the steel plate located between binding bolts; the main factors influencing load-carrying capacity included thickness of the steel plate, type of injected material, and initial column eccentricity; the working performance of the composite column with epoxy adhesive was better than that with cement grout; and re-distribution of compressive stress existed in the steel plates of the column. Also, the ratio of service load-carrying capacity to ultimate capacity of the steel-plate-masonry composite column is about 70%.

It is a challenging problem to design a high performance modulation for mobile satellite communications due to the limited power and bandwidth resource. The paper improves Feher patented Quadrature Phase Shift Keying (FQPSK) by redefining the waveform. The novel FQPSK, with constant envelope, can be used to improve the power efficiency and frequency efficiency of mobile satellite communication. The study shows that the improved FQPSK outperforms conventional FQPSK over AWGN and is immune to the non-linearity of high power amplifier. At last, the impact of flat fading and multi-path fading of channel on the BER performance of improved modulation is analyzed.

The design scheme of a suspension bridge with a super-long-span of 3300 m was taken as an example, and calculating results from 3 mechanics models are compared with each other to study the effects of bending stiffness of cables on stress distribution and curve shape in super-long single suspension cable structures on the basis of the Finite Element Method (FEM) algorithm of ANSYS and the analytical segmental catenary method for cables’ shape-finding. The study shows that the influence of bending stiffness on curve shape-finding of cables is negligible; Although its effects on stress distribution in cross sections of main cables due to dead loads is small, the error of horizontal forces probably results in great one for the calculation of bending moments at the bottom cross-sections of bridge pylons, which needs attention to ensure the structural safety.