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In this paper, the free vibration of functionally graded pipes with initial defects is studied by differential integral method. The pipe model studied is not completely straight, but a functionally graded pipe with initial geometric curvature defects. Firstly, the meso-structure model of functionally graded pipe with initial geometric curvature defect is considered, and the power function model is used to describe the variation law of pipe material along the radial direction of cross section. Secondly, the displacement field equation, the geometric equation, the strain equation and the constitutive equation are given based on the Euler-Bernoulli beam theory. Using the Hamilton principle, the vibration governing differential equation of the functionally graded pipe with initial geometric curvature is derived, and it is dimensionless. Then, the dimensionless control equation and the boundary conditions are discretized by the differential quadrature method to obtain the characteristic equation; Finally, the obtained results are compared with the existing literature data to verify the applicability and accuracy of the differential quadrature method. The effects of gradient index, defect amplitude and fluid flow rate on the initial small curvature functionally graded defect pipe were discussed. The results show that the transition of the pipe from the ceramic material on the inner surface to the SUS304 stainless steel on the outer surface is more reasonable than the transition of the pipe from the ceramic material on the outer surface to the SUS304 stainless steel on the inner surface. [ABSTRACT FROM AUTHOR]

"The Expert Group on Tumor Ablation Therapy of Chinese Medical Doctor Association, The Tumor Ablation Committee of Chinese College of Interventionalists, The Society of Tumor Ablation Therapy of Chinese Anti-Cancer Association and The Ablation Expert Committee of the Chinese Society of Clinical Oncology" have organized multidisci-plinary experts to formulate the consensus for thermal ablation of pulmonary subsolid nodules or ground-glass nodule (GGN). The expert consensus reviews current literatures and provides clinical practices for thermal ablation of GGN. The main contents include: (1) clinical evaluation of GGN, (2) procedures, indications, contraindications, outcomes evaluation and related complications of thermal ablation for GGN and (3) future development directions. [ABSTRACT FROM AUTHOR]

In industrial fields, wireless sensor networks have been massively deployed for the purpose of data collection. For the various application scenarios of smart manufacturing in Industry 4.0, versatile production tasks demand dynamic features both in production lines and manufacturing processes. Therefore, the design and performance of the corresponding data collection mechanisms are facing unprecedented challenges. In this work, we propose a unified data description and management framework. This framework possesses high flexibility that it is able to identify an unknown data type and accord an adequate description. Besides, the scalability of this framework enables the provision of handy interfaces for the exploitation of stored data. Then, we develop two network connectivity models in one dimension and two dimensions. These two models greatly facilitate the measurement of the level of connectivity for a wireless sensor network. At last, we elaborate a two-hop multi-sink routing scheme to alleviate the flooding problem. This scheme contains a novel r- Kruskal algorithm for the sink nodes and an efficient two-hop routing method for the whole network. The flooding effect can be neatly controlled with the two-hop scheme. Extensive experiments are conducted to evaluate our proposal. Simulation results show that our model has excellent adaptability to the scale of the network and possesses satisfactory performance in terms of both message overhead and data availability. [ABSTRACT FROM AUTHOR]

The information comes from physical shop floor and manufacturing process is closely monitored and coordinated under the framework of cyber-physical system in Industry 4.0. Wireless sensor networks are deployed to collect the massive amounts of data generated in a smart factory. Researchers employ sensor cloud to facilitate the management of a large scale deployment of wireless sensor nodes. Facing with lots of concurrent sensing demands of users administrators of a manufacturing network need to deal with the mapping of physical sensors and virtual sensors. We propose a cost-efficient virtual sensor management scheme which is able to accord an overall virtual sensor instantiation result for the whole manufacturing network. Both the architecture of the manufacturing network and the application scenario are modeled by entities, actions, and messages. The key component of the proposed model is called k resource scheduler. Different resource scheduling algorithms could be applied to the k resource scheduler, and thus make our model flexible. Three resource scheduling algorithms are devised to tackle the problem of virtual sensor management. The effectiveness of the proposed model is verified by simulation experiments and a comprehensive analysis of the experimental results is provided. [ABSTRACT FROM AUTHOR]

Based on the characteristics of large amount of computation, slow running speed and poor real-time quality in virtual reality pose estimate, a monocular camera-based image recognition method is proposed to obtain the spatial pose data of the object to be tracked efficiently. Mean-Shift algorithm is used to solve the problem of dynamic blur caused by high-speed rotation of objects in images. By obtaining the a priori shape data and size of the object to be tracked, so on as the constraint condition, the coordinates of the points marked by ArUco and the camera data of the calibrated data are obtained, and the three-dimensional space pose of the object to be tracked is obtained in real time in the world coordinate system. [ABSTRACT FROM AUTHOR]

In the virtual reality space, the positioning accuracy of headwear device has a great influence on user experience. The equipment with precise space positioning has a better sense of immersion and realizes the displacement synchronization of virtual and real space. The BP neural network is used for modeling positioning. Mass data can’t be loaded in a single machine memory, and it can’t be done in bulk. In this paper, Multi-file training rules are used to adjust the logic structure of the algorithm to achieve incremental learning. the neural network in the training process has memory function for the historical data. The experimental results show that the incremental BP algorithm can realize the location function and predict the larger effect. [ABSTRACT FROM AUTHOR]

To compare and analyze the effect and the safety of the paclitaxel-eluting stents and paclitaxel-eluting balloon in the treatment for in-stent rest enosis. 120 cases, who had been undergone percutaneous coronary intervention (PCI) in the Department of Cardiology of Henan Provincial People's Hospital from January 2012 to January 2014 were selected. All the patients were randomly treated with paclitaxel-eluting balloon or paclitaxel-eluting stents. The former were divided into different groups that named group A and the later group B. All the selected patients signed the informed consent on interventional therapy and be given anti-platelet drugs before operating. At the same time, they had routine examination, like chest X-ray, ultrasound, biochemical detection, Myocardial injury markers. (1) The two groups had no significant difference in the general information (P>0.05); (2) The success rate in the two groups reached 100% and (3) All the patients were visited in the 9th, 12th and 24th month to see if any of them was dead. The reexamination results in the 9th month showed that both drug-eluting balloon and drug-eluting stents were safe and effective in treating coronary artery in-stent restenosis. In addition, drug-eluting balloon was more effective than drug-eluting stents to prevent from the in-stent restenosis. [ABSTRACT FROM AUTHOR]

The microstructure and the mechanical property of Nb-Ti-Ni alloy membranes for hydrogen permeation were investigated. XRD and SEM were employed to characterize the structures of Nb-Ti-Ni alloys, and the bending property of the alloy membranes was measured by three-point bending tests. The results indicate that the as-prepared alloy is mainly composed of two phases, i.e. the primary bcc-Nb(Ni, Ti) solid solution phase, and [bcc-Nb(Ni, Ti)+ β 2-NiTi] eutectic phase. The former acts as functional cell for hydrogen permeation and the later is structural cell to keep the stability of alloy membrane. Mechanical properties of Nb-Ti-Ni alloy membranes have been improved to a certain degree by magnetic heat-treatment (MHT) along the three directions (0°, 45° and 90°). An obvious improvement has been made in the case of N7 sample by MHT at both of 0° and 45°, and in the case of N5 sample by MHT at 90° angle. MHT can lead to the change of grain sizes and grain orientations. In the case of MHT at 0° angle, a tiny bar-like region (consisting of eutectic phase) is formed and spreads along the direction of membrane surface, while some oral-like (or spot-like) region is regularly arranged on the surface, and the region extends vertically to the surface in the case of MHT at 90° angle. It is suggested that suitable MHT is beneficial to the improvement of the bending property of Nb-Ti-Ni alloy membranes. [ABSTRACT FROM AUTHOR]

A series of experiments have been performed to investigate the temperature effects on the structure and the electrochemical properties of LaNi 3.8 Co 0.6 Mn 0.3 M 0.3 ( M =Ni, Al, Cu) hydrogen storage alloys at different temperatures of 238, 273, 303 and 323 K. Samples A, B and C were used to represent LaNi 4.1 Co 0.6 Mn 0.3 (Ni substituted alloy), LaNi 3.8 Co 0.6 Mn 0.3 Al 0.3 (Al substituted alloy) and LaNi 3.8 Co 0.6 Mn 0.3 Cu 0.3 (Cu substituted alloy), respectively. The structures and the electrochemical properties of A, B and C hydrogen storage alloys were investigated by XRD and simulated battery test, respectively. The results reveal that all of the alloys are composed of the homogeneous LaNi 5 phase with a CaCu 5 -type hexagonal structure. The low-temperature properties of the Cu substituted alloy are improved, and the high-temperature discharge capacity of the Al substituted alloy is enhanced. Electrochemical impedance spectroscopy (EIS) analysis shows that the improvement of high-temperature discharge capacity of alloy electrode B is attributed to the formation of dense oxide film to protect the active material from corrosion, which is not favorable to charge-transfer reaction at the interface of electrode-electrolyte. The deterioration in the high-rate dischargeability (HRD) of alloy electrodes B and C are attributed to the degradation of electrochemical kinetics, including both charge-transfer reactions on the electrode surface and hydrogen diffusion in the bulk. Furthermore, the good low-temperature performance of alloy electrode C is due to the improvement of charge-transfer reaction. [ABSTRACT FROM AUTHOR]