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81.
张凤英  刘文怡  杨慧  马睿 《应用声学》2015,23(1):102-105
为全面测控飞行器姿态,设计了一种能实时监测、控制飞行器姿态倾角的远程遥测系统。采用FPGA进行中央逻辑控制,构建了智能变送模块。将上位机作为终端设备,结合步进电机24BYJ48-5V与双轴倾角传感器ROB100,完成步进电机闭环控制,实现-90°~+90°范围内任意倾角值的实时测量与控制,精度达0.5°。通过大量试验结果表明,该系统可靠性高,各项性能指标均满足项目需求。  相似文献   
82.
白光LED智能调光数学模型   总被引:2,自引:2,他引:0  
周锦荣 《发光学报》2015,36(8):953-956
LED灯的光通量不仅受电流的影响,还受到结温变化的影响。针对传统LED调光存在只改变电流大小而忽略结温变化对光通量影响所存在的不足,结合LED结温和管脚温度存在特定的关系,利用实验装置采集HL001WY型Ga N基白光LED在不同管脚温度和正向电流下的光通量实验数据并进行二次项趋势回归,利用定标和归一化方法建立光通量、电流以及管脚温度三者变化关系的数学模型。计算结果表明,利用该方法建立的模型得到的计算数值与实验实际测量值的相对误差小于4.5%。  相似文献   
83.
损伤自诊断自适应智能材料结构的研究   总被引:6,自引:2,他引:6  
本文介绍了一种强度型损伤自诊断自适应智能复合材料结构的研究情况。这种智能材料结构基于电阻应变丝为传感元件,形状记忆合金为动作元件。为使结构具有高的灵敏度及诊断精度,文中研究了传感元件的布置方案,提出了四点布置传感元件的方法。同时采用形状记忆合金为动作元件。在自诊断出损伤后,对相应的SMA激励,以减小损伤或防止其扩展。  相似文献   
84.
Smart grid is referred to a modernized power grid which can mitigate fault detection and allow self‐healing of the system without the intervention of operators. This article proposes an innovative analytical formulation using Markov method to evaluate electric power distribution system reliability in smart grids, which incorporates the impact of smart monitoring on the overall system reliability. An accurate reliability model of the main network components and the communication infrastructure have been also considered in the methodology. The proposed approach was applied to a well‐known test bed (Roy Billinton Test System) and various reliability case studies with monitoring provision and monitoring deficiency are analyzed. This article involves the developing possibilities of communication technologies and next‐generation control systems of the entire smart network based on the real‐time monitoring and modern control system to achieve a reliable, economical, safe, and high efficiency of electricity. The implementations indicate that using an appropriate set of the smart grid monitoring devices for power system components can virtually influence all the reliability indices although the amount of improvement varies between techniques. The proposed approach determined that smart monitoring for which components of the electric power distribution systems are tailored and deduce to major economical benefits. The described approach also reveals which reliability indices drastically influenced using monitoring. © 2014 Wiley Periodicals, Inc. Complexity 21: 99–113, 2015  相似文献   
85.
This paper is the second part of a work devoted to the modelling of thin elastic plates with small, periodically distributed piezoelectric inclusions. We consider the equations of linear elasticity coupled with the electrostatic equation, with various kinds of electric boundary conditions. We derive the corresponding effective models when the thickness a of the plate and the characteristic dimension ϵ of the inclusions tend together to zero, in the two following situations: first, when aϵ, and second, when aϵ tends to zero. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
86.
87.
A multiphysics model is developed to simulate the responsive behavior of smart pH‐/electric‐sensitive hydrogels when immersed into pH buffer solution and subjected to an externally applied electric field, which is termed the MECpHe model. Comparison with experimental data shows the MECpHe model to be accurate and stable. The influence of the externally applied electric voltage is discussed with respect to the distribution of diffusive ionic species and the displacement of the hydrogel strip. The influences of initial charge density and ionic strength on the swelling ratio and the bending deformation of the microgel strip are studied.

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88.
Matrix assisted laser desorption/ionization (MALDI) applications, such as proteomics, genomics, clinical profiling and MALDI imaging, have created a growing demand for faster instrumentation. Since the commonly used nitrogen lasers have throughput and life span limitations, diode-pumped solid-state lasers are an alternative. Unfortunately this type of laser shows clear performance limitations in MALDI in terms of sensitivity, resolution and ease of use, for applications such as thin-layer sample preparations, acceptance of various matrices (e.g. DHB for glycopeptides) and MALDI imaging. While it is obvious that the MALDI process has some dependence on the characteristics of the laser used, it is unclear which features are the most critical in determining laser performance for MALDI. In this paper we show, for the first time, that a spatially structured laser beam profile in lieu of a Gaussian profile is of striking importance. This result enabled us to design diode-pumped Nd : YAG lasers that on various critical applications perform as well for MALDI as the nitrogen lasers and in some respects even better. The modulation of the beam profile appears to be a new parameter for optimizing the MALDI process. In addition, the results trigger new questions directing us to a better understanding of the MALDI process.  相似文献   
89.
王田  邓世名 《运筹与管理》2018,27(5):95-103
本文研究带有风能随机供给的智能电网中传统能源的多周期买电问题,假设存在一个能源运营商集中负责智能电网传统能源的购买和消费。通过构建并求解动态规划模型,找到能源运营商在风能供给不确定性下的传统能源最优多周期买电策略。在最优买电策略下,能源运营商只有在当期电价足够小时才购买传统能源,其买电量与风能分布、价格信息和时间信息有关。在实际数据的基础之上,提供详实的数值实验对比研究了本文的最优买电策略和其他两种策略(实践中只考虑风能估计的策略和放弃利用风能的策略)在最小化总成本方面的效果,并验证了本文的最优买电策略在真实风能数据中的鲁棒性。  相似文献   
90.
Cancer is a group of disorders characterized by uncontrolled cell growth that affects around 11 million people each year globally. Nanocarrier-based systems are extensively used in cancer imaging, diagnostics as well as therapeutics; owing to their promising features and potential to augment therapeutic efficacy. The focal point of research remains to develop new-fangled smart nanocarriers that can selectively respond to cancer-specific conditions and deliver medications to target cells efficiently. Nanocarriers deliver loaded therapeutic cargos to the tumour site either in a passive or active mode, with the least drug elimination from the drug delivery systems. This review chiefly focuses on current advances allied to smart nanocarriers such as dendrimers, liposomes, mesoporous silica nanoparticles, quantum dots, micelles, superparamagnetic iron-oxide nanoparticles, gold nanoparticles and carbon nanotubes, to list a few. Exhaustive discussion on crucial topics like drug targeting, surface decorated smart-nanocarriers and stimuli-responsive cancer nanotherapeutics responding to temperature, enzyme, pH and redox stimuli have been covered.  相似文献   
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