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71.
针对实时监控系统中的运行设备或装置的异常报警信息,设计了基于GSM无线通讯的微机监测系统,实现了多故障远程短信息报警功能,介绍了系统的软硬件设计及主要功能;经应用测试,系统具有宴时性强、稳定性高、投入成本低等特点,能将信息同时发送至多个移动通信终端,已成功应用于农业温室大棚监控系统的实时故障报警,系统也可方便地应用于工厂生产线、金融、交通及家庭安全等方面的远程监测. 相似文献
72.
针对传统MEMS陀螺仪输出信息为模拟量且易受干扰、噪声较大的问题,结合SAR150陀螺仪可以直接输出数字信号的特点,提出了一种新型的数字陀螺仪实时数据采集系统;该系统以FPGA为主控制器,通过SPI接口完成对MEMS陀螺仪SAR150的控制与数据的传输,实现了对陀螺仪输出信号的采集、实时传输及存储;通过将所研制的数据采集系统应用于SAR150陀螺仪测量角速率实验,并对测得数据进行误差分析,实验结果表明:数据采集系统采集输出的角速率值与理论值的绝对误差标准差均小于0.2°/s;且该系统的可靠性高、实时性好,为后续的陀螺仪测试及标定奠定了基础,有一定的工程应用价值。 相似文献
73.
电力抄表系统常通过网络采集和传输电网中的谐波等信息。本文提出了一种适合电力系统的网络设计方案。在STM32F207和DM9161A为核心的硬件平台上,完成了LwIP协议栈的移植,实现了远程终端和上位机通信。使电力系统更具实时性与交互性,并保证了通信的可靠性。 相似文献
74.
设计了一种在NiosⅡ处理器上的CCD数据采集系统。电荷耦合器件(Charge—Coupled Device,CCD)采集到的信号经过前端的差分运放处理后再进行A/D转换,转换后的数据存储于外部SDRAM中,被读取后显示在LCD上。本文重点介绍了各器件的电路设计和驱动程序的编写。实践表明,该设计成本低,实时性较高。 相似文献
75.
We introduce a novel method for synthesizing dance motions that follow the emotions and contents of a piece of music. Our method employs a learning-based approach to model the music to motion mapping relationship embodied in example dance motions along with those motions' accompanying background music. A key step in our method is to train a music to motion matching quality rating function through learning the music to motion mapping relationship exhibited in synchronized music and dance motion data, which were captured from professional human dance performance. To generate an optimal sequence of dance motion segments to match with a piece of music, we introduce a constraint-based dynamic programming procedure. This procedure considers both music to motion matching quality and visual smoothness of a resultant dance motion sequence. We also introduce a two-way evaluation strategy, coupled with a GPU-based implementation, through which we can execute the dynamic programming process in parallel, resulting in significant speedup. To evaluate the effectiveness of our method, we quantitatively compare the dance motions synthesized by our method with motion synthesis results by several peer methods using the motions captured from professional human dancers' performance as the gold standard. We also conducted several medium-scale user studies to explore how perceptually our dance motion synthesis method can outperform existing methods in synthesizing dance motions to match with a piece of music. These user studies produced very positive results on our music-driven dance motion synthesis experiments for several Asian dance genres, confirming the advantages of our method. 相似文献
76.
Wei-Lan Suo Bo Feng Zhi-Ping Fan 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2012,16(3):471-483
The decision making trial and evaluation laboratory (DEMATEL) method is a useful tool for analyzing correlations among factors
using crisp values. However, the crisp values are inadequate to model real-life situations due to the fuzziness and uncertainty
that are frequently involved in judgments of experts. The aim of this paper is to extend the DEMATEL method to an uncertain
linguistic environment. In this paper, the correlation information among factors provided by experts is in the form of uncertain
linguistic terms. A formula is first presented to transform correlation information from uncertain linguistic terms to trapezoidal
fuzzy numbers. Then, we aggregate the transformed correlation information of each expert into group information using the
operations of trapezoidal fuzzy numbers. The importance and classification of factors are determined via fuzzy matrix operations.
Furthermore, a causal diagram is constructed to vividly show the different roles of factors. Finally, an example is used to
illustrate the procedure of the proposed method. 相似文献
77.
James?Eves Vassili?V.?ToropovEmail author Harvey?M.?Thompson Nik?Kapur Jian?Fan Daniel?Copley Adrian?Mincher 《Structural and Multidisciplinary Optimization》2012,45(5):739-745
Supersonic jet pumps are simple devices with no moving parts, where a high velocity (primary) flow is used to pump a second
fluid. In this paper, Computational Fluid Dynamics (CFD) is combined with an optimization framework in order to develop a
tool for the rapid generation of jet pump designs. A key feature of the problem formulation is the transformation of the jet
pump design parameters in terms of geometric ratios. This approach dramatically reduces the number of unrealistic designs
covered by the Design of Experiments. Optimal Latin Hypercubes for surrogate model building and model validation points are
constructed using a permutation genetic algorithm and design points are evaluated using CFD. Surrogate models of primary and
entrained flow rates are built using a Moving Least Squares approach. A series of optimizations for various pump sizes are
performed using a genetic algorithm and Sequential Quadratic Programming, with responses calculated from the surrogates. This
approach results in a set of optimized designs, from which pumps for a wide range of flow rates can be interpolated. 相似文献
78.
The effect of nitrogen and nickel on the austenite stability and the structural changes as a result of cold work of an Fe-12Cr-23Mn alloy steel has been examined by transmission electron microscopy and X-ray analysis. Prestrain was performed either at room temperature or at 200° C. Final strain was carried out at liquid nitrogen temperature. The volume fraction of strain-induced martensite decreased by 40% and 12% due to the addition of 2.43% Ni and 0.11% N, respectively, despite whether prestrain was performed or not. The mechanisms are discussed in terms of the phase, stacking faults, dislocation cells and dislocation tangles induced by prestrain and final strain. 相似文献
79.
The effect of pre-strain on the strain-induced martensitic transformation of an Fe-12Cr-23Mn austenitic steel has been investigated through transmission electron microscopy and X-ray analysis. Pre-strain was performed either at room temperature or at 200° C. Final strain was carried out at liquid-nitrogen temperature. The phase was shown to form on {1 1 1} planes of the austenite matrix predominantly by overlapping of stacking faults. The martensite transformation sequence was . Nucleation of the phase mainly occurred at intersections of bands. Austenite stability was shown to increase by pre-strain at 25° C or 200° C. Pre-strain at 200° C has a greater effect on austenite stability than does pre-strain at 25° C. The mechanism was discussed in terms of martensite transformation rate and various substructures introduced during straining. Work hardening was shown to depend on the degree of pre-strain and final strain. The correlation between work hardening and substructures introduced during straining was examined. 相似文献
80.
研究了一种制造低电电压氧化锌压敏电阻器的方法。在基本成分的基础上适当加入二氧化钛可降低梯度电压(V1mA/mm),适量掺硼和改进热处理工艺可减小元件的漏电流和提高其稳定性。 相似文献