Applied Mechanics and Materials Vols. 631-632

Abstract: Scenery spot entity resolution is the basis on tourism information integration and tourism recommend. Entity resolution can’t be achieved through one stage between entities for most entity resolution, and can’t be obtained the satisfied result as expect. However, we can use the multistage mixed attributes entity resolution model to improve the correct result. We are adopt the multistage that concludes k-means clustering in the step 1, and the bucket algorithm to identify entities in the step 2. What’s more, we are optimize the bucket algorithm in our paper. Our experience result is effective.

Abstract: Based on the basic principle of the phase locked loop, analyzes the structural characteristics of the loop filter technology and ADF4350; secondly, design and analysis of two order passive low pass filter, three order passive low pass filter, two order active low-pass filter, with parameters such as bandwidth, phase margin ADF4350 PLL, selection the loop filter is suitable for the actual situation; using ADIsimPLL software to determine the parameters and realize the optimization of S parameters on circuit simulation, optimized and then use ADS software to observe. Finally, according to the results of analysis to adapt to the situation three kinds of filter structure of ADF4350phase locked loop.

Abstract: An ultra-wideband (UWB) circularly polarized complex spiral antenna with low radar cross section (RCS) is proposed in this paper. By replacing the metal reflect board of the antenna with a novel UWB frequency selective surface (FSS), the RCS of the spiral antenna is significantly reduced in a wide frequency range, while the radiation performances of the spiral antenna are maintained. The proposed antenna operates over the frequency band between 2GHz to 6.5GHz under the condition of axial ratio<3dB and |S₁₁| < - 10dB. Simulation and measurement results demonstrate the validation of broadband spiral antenna RCS reduction by using the novel UWB FSS.

Abstract: Currently, in alpine region, the main way of heating for the greenhouse is coal heating in winter. This heating method has many drawbacks. During the winter heating period greenhouse will consume large amounts of coal and produce large amounts of pollution. In addition, coal heating also relates to the issue of fire safety, there is security risk. Therefore, using new energy for heating to instead of coal fire heating has a very important significance. Wind and solar energy have the great application prospects and both of them are new clean energy resources which the technology is more mature. In this paper, the design of the greenhouse system use renewable and clean energy as the primary energy supply. The design uses “wind and solar hybrid system” to provide energy for the greenhouse. The system takes efficient energy storage and conversion device for heating the air and soil in the greenhouse, system can meet its own needs and ensure the temperature is appropriate for growth of plants in the greenhouse. Besides, the system can run without other energy supplement in the whole operation cycle. At the same time, this greenhouse system does not produce any harmful pollutants, so that it achieves the full-year zero-emission operation.

Abstract: The Smart Grid uses two-way flows of electricity and information to create a widely distributed automated energy delivery network, and Vehicle-to-Grid (V2G) and Virtual Power Plant (VPP) are two innovative smart grid applications. This survey focuses on V2G implementation through VPPs. First, the concept of V2G and its architectures are introduced. Then VPP, a new power plant concept and its corresponding control methods are described. Finally, implementation strategies of V2G through VPPs are categorized.

Abstract: In modern society, burglaries occur frequently, showing such crimes more high-tech, intelligent trend in recent years. People pay more and more attention to home security. Requirements for home security systems also further improve. In order to establish a sound and reliable home security system, a combination of Zigbee and STM32 terminal acquisition system, achieving low power consumption, data visualization has come true. Compared with traditional alarm systems, this home security terminal design uses new hardware, with smaller volume, easier installation and some data analysis capabilities, making the security system more secure and reliable. The terminals giving a further improve to home security systems, achieving a low cost, low power requirements, have a more broad application prospects and market.

Abstract: This paper presents a bandgap reference and an output-capacitorless LDO regulator with adaptive power transistors. The bandgap reference consists of a current reference circuit, a bipolar transistor and proportional-to-absolute-temperature (PTAT) voltage generators. The proposed LDO improves load transient and light load efficiency by permitting the regulator to transform itself between 2-stage and 3-stage topologies, depending on the load current condition. Cadence simulation with SMIC 0.18 μm process shows that the bandgap reference generates a reference voltage 569 mV and the quiescent current is only 0.23 μA, the proposed LDO generates an output voltage 1 V, the quiescent current is 0.88 μA (including bandgap reference) at no-load condition, the undershoot /overshoot voltage is 187 mV/152 mV and the settling time is 5 μs as load current suddenly changes from 0 to 100 mA, or vice versa.

Abstract: Varactor to replace commonly variable capacitance is applied to the tuner. This paper presents the voltage-controllable band-pass filter design method. The filter constitutes of operational amplifier, resistors, varactor MV209 and parallel LC resonant circuit. Center frequency range of the band-pass filters is from 19MHz to 25MHz controlled with DC voltage. It derives the transfer function of the filter and function expression of junction capacitance with reverse voltage. The frequency response of filter simulation and experimental results are given. Key words: Varactor; Band-Pass Filter; Voltage-Controllable Filter; Junction Capacitance

Abstract: The purpose of this article is to establish a microwave field intensity standard device to calibrate the high-frequency field probe with frequency range from 1GHz to 18GHz and maximum field amplitude up to 10mW/cm2(200V/m),which can satisfy the calibration requirements of field probe for electromagnetic compatibility test.

Abstract: This paper studies the influence of different control modes in the rectifier side (constant current control, constant power control) on commutation failure in UHVDC transmission system. The study is based on Yunnan-Guangdong ±800kV UHVDC transmission system and simulated in PSCAD/EMTDC. A wealth of simulation results indicate that the control ability of the constant current control on commutation failure caused by the critical voltage ratio of inverter transformer increased is worse than the constant power control; the control ability of the constant current control on commutation failure caused by three-phase grounding fault happens at inverter side AC bus is worse than the constant power control; The control ability of the constant current control on commutation failure caused by phase to phase short circuit fault or single-phase ground fault happens at inverter side AC bus is worse than the constant power control.