基于密度矩阵和卫星修正的台风中心定位仿真

针对当前方法在对台风中心进行定位时存在准确性不高、收敛速度较慢的问题,提出一种新的台风中心定位方法,采用能量系数、熵值、对比度、相关系数以及局部平稳系数描述台风卫星云图的纹理特征,求得台风卫星云图的密度矩阵,从中提取云图灰度平均纹理特征、小梯度优势特征和梯度均匀性纹理特征,并对其进行阈值化处理和正规化处理,完成台风卫星云图的预处理;构建台风中心定位最优目标函数并进行求解,完成台风中心初步定位,在此基础上剔除不合理台风中心位置坐标,提高台风中心定位精度。实验结果证明,所提方法在进行台风中心定位时,其定位精确度相比传统方法有很大提高,另外完成台风中心定位所需迭代次数明显减少。以上实验结果说明所提方法能够实现不同类型台风中心的准确定位,且收敛速度快。     

Language acceptability of finite automata based on theory of semi‐tensor product of matrices

Using the theories of many‐valued logic and semi‐tensor product of matrices (STP), this paper investigates how to mathematically determine whether or not a regular language is recognized by finite automata (FA). To this end, the dynamic behaviour of FA is first formulated as bilinear dynamic equations, which provides a uniform model for deterministic and non‐deterministic FA. Based on the bilinear model, the recognition power of FA understanding of regular languages is investigated and several algebraic criteria are obtained. With the algebraic criteria, to judge whether a regular sentence is accepted by a FA or not, one only needs to calculate an STP of some vectors, rather than making the sentence run over the machine as traditional manners. Further, the inverse problem of recognition is considered, an algorithm is developed that can mathematically construct all the accepted sentences for a given FA. The algebraic approach of this paper may be a new angle and means to understand and analyse the dynamics of FA.     

Limit behaviors of extended Kalman filter as a parameter estimator for a sinusoidal signal

In this note, the basic limit behaviors of the solution to Riccati equation in the extended Kalman filter as a parameter estimator for a sinusoidal signal are analytically investigated by using lim sup and lim inf in advanced calculus. We show that if the covariance matrix has a limit, then it must be a zero matrix.     

基于模糊状态观测器的核反应堆功率T-S模糊积分控制系统

为提高核反应堆运行的负荷跟随能力,设计了基于T-S模糊模型的包含模糊状态观测器的积分控制系统。该方法将非线性的点堆动力学方程在一些选定工况点进行线性化,采用并行分布补偿（PDC）方法,设计模糊积分控制器和模糊状态观测器,以相对于额定功率平衡状态的相对中子密度为前件变量,构造T-S模糊控制系统。引入模糊状态观测器,成功解决了部分状态变量不能测量的困难。使用线性矩阵不等式（LMI）方法进行稳定性分析,保证了此控制系统的大范围稳定性。仿真结果验证了这种控制系统能在大范围运行工况下工作良好。     

鲁棒PID控制器的H∞回路成形优化设计及其在蒸汽发生器水位控制中的应用

针对H_∞回路成形设计,提出了一种基于线性矩阵不等式技术的PID型权函数优化算法。结合静态H_∞回路成形控制器综合,给出了一种系统的鲁棒PID迭代优化方法。基于所提方法设计了蒸汽发生器水位控制系统的PID型主控制器。仿真结果表明,所设计控制系统具有较好的鲁棒性能和鲁棒稳定性,综合控制品质优于全阶权函数优化（或本文所提PID型权函数优化）和标准控制器综合相结合的方法。     

Design and evaluation of an optimized W/Cu interlayer for W monoblock components

Divertor plasma-facing components of future fusion reactors should be able to withstand heat fluxes of 10-20 MW/m² in stationary operation. Tungsten blocks with an inner cooling tube made of CuCr1Zr, so-called monoblocks, are potential candidates for such water-cooled components. To increase the strength and reliability of the interface between the W and the cooling tube of a Cu-based alloy (CuCr1Zr), a novel advanced W-fibre/Cu metal matrix composite (MMC) was developed for operation temperatures up to 550 °C. Based on optimization results to enhance the adhesion between fibre and matrix, W fibres (W_f) were chemically etched, coated by physical vapour deposition with a continuously graded W/Cu_PVD interlayer and then heated to 800 °C. The W_f/Cu MMC was implemented by hot-isostatic pressing and brazing process in monoblock mock-ups reinforcing the interface between the plasma-facing material and the cooling channel. The suitability of the MMC as an efficient heat sink interface for water-cooled divertor components was tested in the high heat flux (HHF) facility GLADIS. Predictions from finite element simulations of the thermal behaviour of the component under loading conditions were confirmed by the HHF tests. The W_f/Cu MMC interlayer of the mock-ups survived cyclic heat loads above 10 MW/m² without any damage. One W block of each tested mock-up showed stable thermal behaviour at heat fluxes of up to 10.5 MW/m².     

峰位微扰动修正在构建高斯响应矩阵中的应用研究

现有的高斯响应矩阵在对高分辨率γ能谱进行重建时,极易出现假峰、峰位漂移等问题。本文针对测量条件（温/湿度、电压波动等）微弱变化引起峰位扰动进而影响高斯响应矩阵重建结果准确度的问题,通过引入微扰动修正因子,对现有高斯响应矩阵进行修正。采用IAEA重峰分解测试谱及GMX40P高纯锗探测器实测能谱对修正前后的高斯响应矩阵进行谱线解析测试。结果表明：通过修正后响应矩阵重建的能谱,其峰位与实际峰位保持一致,净峰面积的相对偏差分别低于1025%和550%。     

Nonreciprocal properties of 1D magnetized plasma photonic crystals with the Fibonacci sequence

In this paper, the nonreciprocal properties of a novel kind of 1D magnetized plasma photonic crystals(MPPCs) with the Fibonacci sequence are investigated. The isolation of the proposed 1D MPPCs is also used to analyze the nonreciprocal properties. Compared to the conventional 1D MPPCs with periodic structure, the nonreciprocal performance can be significantly improved.The effects of several parameters of the proposed 1D MPPCs on the nonreciprocal properties are studied by the transfer matrix method, which includes the incident angle, order of the Fibonacci sequence, plasma frequency, plasma cyclotron frequency and plasma filling factor. The obtained results show that the nonreciprocal propagation properties can be improved by increasing the values of the plasma cyclotron frequency and incident angle, but they will worsen by blindly increasing the order of the Fibonacci sequence, plasma frequency and filling factor of plasma.The peaks of transmittance also are obviously reduced. In addition, the value of isolation will increase with increasing the incident angle, order of Fibonacci sequence, plasma frequency and plasma filling factor. However, when the plasma cyclotron frequency is increased, the value of isolation will be increased at lower frequencies, but is almost unchanged at higher frequencies.     

有机硅环氧树脂及其复合材料的光固化研究

通过研究光引发剂的种类、用量、光照时间和光敏剂等对树脂光固化后凝胶率的影响,确定了ES-06有机硅环氧树脂光固化的工艺条件,在质量分数分别为5%的二苯基碘鎓六氟磷酸盐光引发剂和5.5%的多元醇链转移剂作用下,光照10 min后紫外光开环聚合产物的凝胶率可达80%.利用湿法手工铺叠工艺和光固化技术,制备了玻璃布/有机硅环氧树脂复合材料,测试并分析比较了有机硅环氧和双酚A环氧复合材料的力学性能.结果表明,光固化有机硅环氧树脂基复合材料层板的拉伸强度和层间剪切强度较优,分别为158.5 MPa和9.9MPa,而两者的弯曲性能和拉伸模量相当.     

Preparation of mixed matrix composite membrane for hydrogen purification by incorporating ZIF-8 nanoparticles modified with tannic acid

The incompatibility between nanofillers and polymer, caused by the agglomeration of nanoparticles and their weak interaction with each other, is still a challenge to develop mixed matrix composite membrane. Herein, we introduced the ZIF-8-TA nanoparticles synthesized by in situ hydrophilic modification into the hydrophilic poly(vinylamine) (PVAm) matrix to prepare composite membranes for H₂ purification. The dispersion of ZIF-8 in water was improved by tannic acid modification, and the compatibility between ZIF-8 particles and PVAm matrix was enhanced by chemical crosslinking between the quinone groups in oxidized tannic acid (TA) and the amino groups in PVAm. Moreover, the compatibility between hydrophobic polydimethylsiloxane (PDMS) gutter layer and hydrophilic separation layer was achieved by the adhesion of TA-Fe³⁺ complex to the surface of PDMS layer during membrane preparation. The interlayer hydrophilic modification and the formation of separation layer were accomplished in one step, which simplified the preparation process. The experimental results indicated that when the TA addition used for modification was 0.5 g and the ZIF-8-TA_0.5 content in membrane was 12 wt%, the prepared membrane showed the best separation performance with the CO₂ permeance of 987 GPU and the CO₂/H₂ selectivity of 31, under the feed gas pressure of 0.12 MPa.