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诱导式卫星欺骗干扰可诱导航空器逐渐偏离预定航迹,难以被发现,因此及时有效地检测干扰是飞行安全的保障。在现有紧组合导航体制基础上,设计了一种基于误差估值累加开环校正的紧组合导航结构,并证明了其性能与传统闭环校正紧组合导航性能等效。在此结构中,将紧组合导航系统与自适应序贯概率比检测方法结合,提出了一种基于误差估值累加开环校正的诱导式欺骗检测方法,融合紧组合导航信息与其他不受欺骗影响的导航信息,构建欺骗检测统计量进行诱导式欺骗检测。仿真结果表明,开环校正结构可避免随时间累加的惯性导航系统误差所导致的组合导航滤波器发散问题,同时欺骗检测方法可进一步提高算法对“最坏”情形下微小诱导式欺骗的检测效果。 相似文献
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To efficiently link the continuum mechanics for rocks with the structural statistics of rock masses,a theoretical and methodological system called the statistical mechanics of rock masses(SMRM)was developed in the past three decades.In SMRM,equivalent continuum models of stressestrain relationship,strength and failure probability for jointed rock masses were established,which were based on the geometric probability models characterising the rock mass structure.This follows the statistical physics,the continuum mechanics,the fracture mechanics and the weakest link hypothesis.A general constitutive model and complete stressestrain models under compressive and shear conditions were also developed as the derivatives of the SMRM theory.An SMRM calculation system was then developed to provide fast and precise solutions for parameter estimations of rock masses,such as full-direction rock quality designation(RQD),elastic modulus,Coulomb compressive strength,rock mass quality rating,and Poisson’s ratio and shear strength.The constitutive equations involved in SMRM were integrated into a FLAC3D based numerical module to apply for engineering rock masses.It is also capable of analysing the complete deformation of rock masses and active reinforcement of engineering rock masses.Examples of engineering applications of SMRM were presented,including a rock mass at QBT hydropower station in northwestern China,a dam slope of Zongo II hydropower station in D.R.Congo,an open-pit mine in Dexing,China,an underground powerhouse of Jinping I hydropower station in southwestern China,and a typical circular tunnel in Lanzhou-Chongqing railway,China.These applications verified the reliability of the SMRM and demonstrated its applicability to broad engineering issues associated with jointed rock masses. 相似文献
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Wenhui Zhu Haizhen Huan Ying Bu Xuepeng Li David Shiuan Jianrong Li Xiaotao Sun 《International Journal of Food Science & Technology》2019,54(6):2159-2168
Protein oxidation is considered as an important issue in food preservation process. In the present study, the potential influence of protein oxidation on water holding capacity and protein structure of jumbo squid (Dosidicus gigas) mantle was investigated. After the hydroxyl radical oxidation, it was found that the carbonyl, surface hydrophobicity and dityrosine content of myofibrillar protein significantly increased (P < 0.05), while the content of total sulphydryl decreased significantly (P < 0.01). Meanwhile, the fluorescence intensity of squid was weakened, and the maximum absorption peak of fluorescence red shift as the H2O2 concentration increased. The sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) showed that not only the protein cross-linking but also degradation could have occurred. The content of α-helix decreased, the content of β-sheet, β-turn and the unordered structures increased after oxidation. In addition, oxidation resulted in a decrease in water holding capacity. Taken together, oxidation resulted in the damage of the myofibrillar structure, the increase in muscle loss rate and the decrease in water holding capacity. 相似文献
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Manish Aggarwal 《国际智能系统杂志》2019,34(7):1524-1554
A new family of attitudinal discrete choice models is proposed by considering the attitudinal character and the weight vector, both of which are specific to a decision maker (DM). Given the attribute values of different alternatives, the proposed models give varying choice probabilities, as per the DM's-specific attitudinal character and the weight vector. It is also shown that the conventional discrete choice models are the special cases of the proposed attitudinal models. The proposed choice models are also generalized through an additional parameter to add to their capabilities. An application on real data is included to demonstrate their usefulness in the real world. 相似文献
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This study focuses on the asynchronous control problem for two‐dimensional discrete‐time hidden Markovian jump systems where the mode observation conditional probability matrix is partly known. Considering the original system modes are invisible, the observed modes emitted from an observer serve as an alternative for stability analysis and controller design where a mode observation conditional probability matrix is constructed to characterize the emission between system modes and observed modes. Specially, only partly known information of the mode observation conditional probability matrix is accessible. With the introduction of the free‐connection weighting matrices, the asymptotic mean square stability criterion is firstly derived based on Lyapunov method. This introduction provides a further degree of relaxation and less conservatism is therefore achieved. Secondly, we present synthesis conditions for asynchronous state feedback controller design given in terms of a set of interconnected linear matrix inequalities. Moreover, cluster concept based on the partitions of observed modes is adopted which helps to decrease the number of controllers and simplify the design complexity. A numerical example, regarding the cases with and without clustering of the observed modes, is presented to illustrate the effectiveness of the proposed method. 相似文献
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针对渗透水压力引起堤防渗透破坏问题,以堤防渗透破坏风险为目标,考虑堤防计算水位条件和土层渗透系数的不确定性,建立了堤防渗透破坏风险计算模型。以长江武惠堤17+750断面为例,对汉口水文站水位监测资料进行分析并拟合水位概率密度函数,对该断面渗流规律进行有限元分析,从而拟合渗透破坏概率密度函数,以此建立该断面堤防渗透破坏风险定量表达式。研究结果表明,武惠堤17+750断面堤防在警戒水位与防洪设计水位下,渗透破坏概率分别为0.442 9、0.764 0,渗透破坏风险分别为0.001 421、0.002 52;堤防渗透破坏风险随着堤外水位的升高而增加,但在防洪设计水位内运行时,堤防渗透破坏风险低,堤防渗流安全可得到有效控制。 相似文献