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The topology concept in the condensed physics and acoustics is introduced into the elastic wave metamaterial plate, which can show the topological property of the flexural wave. The elastic wave metamaterial plate consists of the hexagonal array which is connected by the piezoelectric shunting circuits. The Dirac point is found by adjusting the size of the unit cell and numerical simulations are illustrated to show the topological immunity. Then the closing and breaking of the Dirac point can be generated by the negative capacitance circuits. These investigations denote that the topological immunity can be achieved for flexural wave in mechanical metamaterial plate. The experiments with the active control action are finally carried out to support the numerical design. [ABSTRACT FROM AUTHOR]

To improve the efficiency of the conventional boost-type power factor correction (PFC) converters with the diode bridge circuit, the PFC converters of bridgeless category are often used. Due to no series-connected switches and no short-through risks, the dual-boost half-bridge (DBHB) circuit is used as the PFC converter in this paper. In order to simplify the conventional two-loop control scheme and reduce the number of sensors, the behaviors of the DBHB PFC converter are studied and its equivalent single-switch model is developed. Then, the current sensorless control for the DBHB PFC converter is proposed to achieve voltage regulation and yield sinusoidal input current in phase with the input voltage without sensing any current. In addition, the proposed method is able to balance capacitor voltages naturally without adding any voltage balancing control loop. An 800-W DBHB PFC prototype is implemented to evaluate the control performance. Both simulation and experimental results are provided to demonstrate the proposed current sensorless control method. [ABSTRACT FROM AUTHOR]

This paper presents a new bi-side gate driver integrated by indium-zinc-oxide thin film transistors (IZO TFTs). Our optimized operate method can achieve high speed performance by employing a lower duty ratio (25%) CK2 with its pulse located in the middle of the pulse of CK2L to fully use the bootstrapped high voltage of node Q. In addition, the size of devices is optimized by calculation and simulation, and the function of the proposed gate driver is predicted by the circuit simulation. Furthermore, the proposed gate driver with 20 stages is fabricated by the IZO TFTs process. It is shown that a 2.6 μs width pulse with good noise-suppressed characteristic can be successfully output at the condition of R load = 6 kΩ and C load = 150 pF. The power consumption of the proposed gate driver with 20 stages is measured as 1 mW. Hence, the proposed gate driver may be applied to the display of 4K resolution (4096 × 2160) at a frame rate of 120 Hz. Moreover, there is a good stability for the proposed gate driver under 48 h operation. [ABSTRACT FROM AUTHOR]

Introduction: We simulate and analyze Total Health Expenditure (THE) in financial sources and other economic indicators (such as THE per capita, GDP, etc.) in a province of China from 2002 to 2012 on System Dynamics. Methods: Based on actual data and certain mathematical methods, we use system dynamic software to construct a logic model for THE and changing proportions, and thus simulate the actual conditions of development and changes in THE. Results: According to the simulation results, the government possess the largest investment in the average annual growth rate of THE, which was 25.16 % in 2012. Social investment comprises the majority of the possession ratio, which was up to 41.20 %. Conclusions: The personal investment growth rate decreased by almost 21 %, but the total amount of personal investment increased by 28075 million yuan, which is far higher than the increase in government investment. Individuals are still the main carriers of health care expenses. The equity of health financial sources is still poor. The System Dynamics method used in this paper identifies a dynamic measurement process, provides a scientific basis for simulation and analysis of the changes in THE and its key constraining factors, as well as put forward suggestions for the improvement of equity of health financial sources. [ABSTRACT FROM AUTHOR]

Leveraging multithreading on embedded multicore platforms has been proven effective on handling the increasing resolutions of target stimuli of object detection. However, complex tradeoffs and correlated design impacts between a parallel application and the underlying multicore platform necessitate an effective and adaptable multithreaded design. This paper introduces a hybrid multithreaded object detection with high parallelism and extensive data reuse. A self adaptable flow is proposed to adjust the multithreaded object detection to fully exploit various embedded multicore architectures. The ARM-based cycle accurate simulations of multicore systems have shown the superior performance returned by the proposed design. [ABSTRACT FROM AUTHOR]

Abstract: This paper provides a numerical and experimental analysis on precipitation and particulate fouling in corrugated plate heat exchangers with different geometric parameters which are plate height, plate spacing, and plate angle. The Realizable κ–ε model with non-equilibrium wall functions is used in the 3D numerical simulation considering the realistic geometries of the flow channel to obtained Nusselt number and wall shear stress, while Von-Karman analogy is used to obtain mass transfer coefficient. Numerical analysis is verified by experimental study. The predicted influence of fluid velocity in fouling resistance is compatible with experimental data that it can help to optimize the design of plate heat exchangers. This investigation significantly simplifies the fouling analysis of complex flow fields and can be used to assess the fouling potential of corrugated plate heat exchangers. [Copyright &y& Elsevier]