In the past 20 years,recycled aggregate concrete(RAC),as a type of low-carbon concrete,has become a worldwide focus of ***,the design methodology for RAC structural components remains a ***,demands for a unified desig...
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In the past 20 years,recycled aggregate concrete(RAC),as a type of low-carbon concrete,has become a worldwide focus of ***,the design methodology for RAC structural components remains a ***,demands for a unified design of natural aggregate concrete(NAC)and RAC components have been ***,this study analyses the necessity of a unified design theory and provides an in-depth demonstration of the strength determination,compressive constitutive relationship,and design method of concrete *** coefficient of variation of RAC strength is found to be generally higher than that of NAC *** compressive and tensile strengths of RAC can be defined and determined using the same method as that used for *** uniaxial compressive constitutive relationship between NAC and RAC has a unified mathematical ***,the elastic modulus of RAC decreases,and its brittleness exhibits an increasing trend compared with that of ***,to unify the design formulae of RAC and NAC components for bearing capacity,modification factors for RAC components are proposed considering safety and ***,the feasibility of the proposed unified time-dependent design theory is demonstrated in terms of conceptual design and structural measures considering the effects of strength degradation and reinforcement *** is believed that this study enriches and develops the basic theory of concrete structures.
Clustering categorical sequences is a problem that arises in many fields. There is a few techniques available in this framework but none of them take into account the possible temporal character of transitions from on...
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Clustering categorical sequences is a problem that arises in many fields. There is a few techniques available in this framework but none of them take into account the possible temporal character of transitions from one state to another. A mixture of Markov models is proposed, where transition probabilities are represented as functions of time. The corresponding expectation-maximization algorithm is discussed along with related computational challenges. The effectiveness of the proposed procedure is illustrated on the set of simulation studies, in which it outperforms four alternative approaches. The method is applied to major life event sequences from the British Household Panel Survey. As reflected by Bayesian Information Criterion, the proposed model demonstrates substantially better performance than its competitors. The analysis of obtained results and related transition probability plots reveals two groups of individuals: people with a conventional development of life course and those encountering some challenges.
The drag-free satellites are widely used in the field of fundamental science as they enable the high-precision measurement in pure gravity fields. This paper investigates the estimation of local orbital reference fram...
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The drag-free satellites are widely used in the field of fundamental science as they enable the high-precision measurement in pure gravity fields. This paper investigates the estimation of local orbital reference frame(LORF) for drag-free satellites. An approach, taking account of the combination of the minimum estimation error and power spectral density(PSD) constraint in frequency domain, is proposed. Firstly, the relationship between eigenvalues of estimator and transfer function is built to analyze the suppression and amplification effect on input signals and obtain the eigenvalue range. Secondly, an optimization model for state estimator design with minimum estimation error in time domain and PSD constraint in frequency domain is established. It is solved by the sequential quadratic programming(SQP) algorithm. Finally, the orbital reference frame estimation of low-earth-orbit satellite is taken as an example, and the estimator of minimum variance with PSD constraint is designed and analyzed using the method proposed in this paper.
Though end-to-end siamese networks have achieved great performance on object tracking owing to offline pre-training with large datasets. They are still liable to fail to track fast moving object and their accuracy suf...
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Though end-to-end siamese networks have achieved great performance on object tracking owing to offline pre-training with large datasets. They are still liable to fail to track fast moving object and their accuracy suffers from the cosine window for mitigating background interference. The cosine window will aggravate the boundary effect and have a negative impact on track. In this paper, we propose an accurate positioning siamese network (FPSiam) for real-time object tracking. This approach can better estimate the search candidate area of the object in the current frame from the previous tracking position and can keep tracking well for the fast moving object. The unbalanced penalty mechanism of the cosine window in the tracking process is avoided. Furthermore, the features of the low-level layers are high-resolution, which is suitable for positioning the object. High-level layers are full of rich semantic features which are suitable for classifying the objects. In order to utilize the advantages of high-level features and low-level features, we introduce a densely connected tracking network. A number of experiments were conducted on five challenging tracking datasets: OTB50, OTB2013, OTB2015, VOT2015, and VOT2016, and the proposed method achieved excellent results on these benchmarks.
In this paper, exact solutions of the generalized Boussinesq-like B(m, n) equation with nonlinear dispersion u(tt) + a(u(n))(xx) + b(u(m))(xxxx) = 0, m, n E R are investigated. As a result, under different parameter c...
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In this paper, exact solutions of the generalized Boussinesq-like B(m, n) equation with nonlinear dispersion u(tt) + a(u(n))(xx) + b(u(m))(xxxx) = 0, m, n E R are investigated. As a result, under different parameter conditions, abundant compactons, peakons and solitary solutions, which include not only some known results but also some new ones, are obtained. The approach we used is simple and also suitable for studying the traveling wave solutions of some other equations. (c) 2006 Elsevier Ltd. All rights reserved.
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