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1.
From the viewpoint of material and structure in the design of bamboo blades of large-scale wind turbine, a series of mechanical property tests of bamboo laminates as the major enhancement materials for blades are presented. The basic mechanical characteristics needed in the design of bamboo blades are brie?y introduced. Based on these data, the aerodynamic-structural integrated design of a 1.5 MW wind turbine bamboo blade relying on a conventional platform of upwind, variable speed, variable pitch, and doubly-fed generator is carried out. The process of the structural layer design of bamboo blades is documented in detail. The structural strength and fatigue life of the designed wind turbine blades are certified. The technical issues raised from the design are discussed. Key problems and direction of the future study are also summarized.  相似文献   

2.
The design of functional observer for a class of discrete systems with time-delay is concerned. The solution to Sylvester function is given. An improved method for the functional observer design is proposed by the condition of linear matrix inequality. In the end,an example is given to illustrate the feasibility of the method.  相似文献   

3.
The pyrotechnic control subsystem plays an important role in opening the solar array of a satellite. Assessing the reliability of the subsystem requires determining the level of a control factor that is needed to cause the desired response and energy output with high probability. A two-phase adaptive design to estimate the level of interest is proposed and studied. The convergence of the design is obtained. A simulation study shows that the estimate is very close to its population value and is robust to the initial guess of the design. As an application, the design is used to assess the reliability of a real pyrotechnic control subsystem.  相似文献   

4.
This paper introduces a method of bootstrap wavelet estimation in a nonparametric regression model with weakly dependent processes for both fixed and random designs. The asymptotic bounds for the bias and variance of the bootstrap wavelet estimators are given in the fixed design model. The conditional normality for a modified version of the bootstrap wavelet estimators is obtained in the fixed model. The consistency for the bootstrap wavelet estimator is also proved in the random design model. These results show that the bootstrap wavelet method is valid for the model with weakly dependent processes.  相似文献   

5.
This paper studies the model-robust design problem for general models with an unknown bias or contamination and the correlated errors. The true response function is assumed to be from a reproducing kernel Hilbert space and the errors are fitted by the qth order moving average process MA(q), especially the MA(1) errors and the MA(2) errors. In both situations, design criteria are derived in terms of the average expected quadratic loss for the least squares estimation by using a minimax method. A case is studied and the orthogonality of the criteria is proved for this special response. The robustness of the design criteria is discussed through several numerical examples.  相似文献   

6.
The theory of optimal design plays a fundamental role in experimental design. Some of the results have been widely applied to the realistic world. In[1], Kiefer proved the optimality of some block designs. In this paper some block-factorial designs are discussed. When a block design d_2(v_2,b,k) is superimposed on other block design d_1(v_1,b,k), the resulting structure is called a block-factorial design and is abbreviated as d_1*d_2. The collection of all such designs is denoted by π(v_1,v_2, bk) or Ω. If d_1,d_2 are uniform and they are orthogonal to each other, the structure can be considered as an orthogonal design with three factors. In[2] Cheng pointed out that  相似文献   

7.
Synchronization and adaptive synchronization of Morse oscillator with periodic forced section is investigated in this paper. Backstepping design is a recursive procedure that combines the choice of Lyapunov function with the design of controller. The proposed approaches offers a syetematic design procedure for synchronization and adaptive synchronization of a large class of continuous-time chaotic systems in the chaos research literature. Simulation results are presented to show the effectiveness of the approaches.  相似文献   

8.
Supersaturated Design with More Than Two Levels   总被引:9,自引:0,他引:9  
gO. IntroductionA fractional factorial design is called supersaturated if the number of factors includedexceeds the limitation for keeping all the factors estimable, ignoring interactions. Sincesupersaturated designS can accommodate large nUInbers of factors, they are thought usefulin screening experhoellts.The research work on tWO-level supersaturated design was st8lted in the late fifties andearly staies (see [1,101). The subject has been gaining more and more renewed interest inthe last …  相似文献   

9.
The concept of t-PBIB design was introduced by Wei Wandi and Yang Benfu as a generalization of G-design and PBIB design. In this paper, a number of 3-associntion schemes and 3-PBIB(2) designs are constructed on the bases of the finite vector space over Fq and the finite unitary geometry over Fq2. Then a number of 3-designs are constructed on the bases of the finite orthogonal geometries over Fq. The parameters of all these designs are computed.  相似文献   

10.
The paper develops a design of optimal Bonus-Malus System (BMS) based on exact equitable credibility,in which the relative error function is taken as loss function. In BMS,both the frequency and the severity components are considered. This design is compared with traditional BMS derived from classical squared-error loss function.  相似文献   

11.
In this paper,a new optimal design criterion--joint model and criterion optimal de-sign criterioon is put forward. The design that is subject to this criterion satisfies many kinds of lin-ear optimal criterion and D-optimal criterion on several experiment models at the same time. Theequivalent condition of this optimal design is given. Its iterative algorithm and the algorithm cover-genee are stated.  相似文献   

12.
This paper proposes a class of linear models with inequable variance, based on background in genetic linkage analysis, and considers the optimal design problem for the hypothesis test of the parameters in such models. To assess a design for the test, a frame of decision theory is established. Under this frame, an admissible minimax design is obtained. It is shown to be not only admissible and minimax in genetic linkage analysis, but best among a reasonable subclass of designs. The power of the test in genetic linkage analysis is substantially improved by using this optimal design.  相似文献   

13.
In this article, we consider the characterization problem in design theory. The objective is to characterize minimum projection uniformity for two-level designs in terms of their complementary designs. Here, the complementary design means a design in which all the Hamming distances of any two runs are the same, which generalizes the concept of a pair of complementary designs in the literature. Based on relationships of the uniformity pattern between a pair of complementary designs, we propose a minimum projection uniformity (MPU) rule to assess and compare two-level factorials.  相似文献   

14.
This paper proposes a sort of new normal forms consisting of observer form and controllable form for nonlinear systems. The conditions for transforming to these normal forms are given, respectively. These normal forms are used to treat the problems of observer design and linearization. The first part of this paper deals with the observer form, and the second the controllable form.  相似文献   

15.
Case-cohort design usually requires the disease rate to be low in large cohort study,although it has been extensively used in practice.However,the disease with high rate is frequently observed in many clinical studies.Under such circumstances,it is desirable to consider a generalized case-cohort design,where only a fraction of cases are sampled.In this article,we propose the inference procedure for the additive hazards regression under the generalized case-cohort sampling.Asymptotic properties of the proposed estimators for the regression coefcients are established.To demonstrate the efectiveness of the generalized case-cohort sampling,we compare it with simple random sampling in terms of asymptotic relative efciency.Furthermore,we derive the optimal allocation of the subsamples for the proposed design.The fnite sample performance of the proposed method is evaluated through simulation studies.  相似文献   

16.
This paper considers local median estimation in fixed design regression problems. The proposed method is employed to estimate the median function and the variance function of a heteroscedastic regression model. Strong convergence rates of the proposed estimators are obtained. Simulation results are given to show the performance of the proposed methods.  相似文献   

17.
For the design of wind turbine blades, the use of a family of specially tailored airfoils is particularly important. The dedicated airfoils can dramatically improve the capability of capturing wind power, reduce the structural weight to save the cost of manufacturing and transportation, and lower the inertial loads as well as the loads due to gust. An overview of the world-wide wind turbine airfoil families developed since 1990’s is presented, such as the S series, the DU series, the Ris? series, and the FFA series. The design and wind-tunnel tests of the Northwestern Polytechnical University (NPU) airfoil family for megawatt-size wind turbines, called the NPU-WA series, are summarized. All tests for the NPU-WA series are carried out in the NF-3 low-speed wind-tunnel with a two-dimensional (2D) test section of 1.6 m?0.8 m and at the Reynolds number ranging from 1.6?106 to 5?106 . The research activities for further improving the NPU-WA airfoils towards lower roughness sensitivity are also reviewed. The development of the new NPU-WA series dedicated for multi-megawatt wind turbines is discussed.  相似文献   

18.
Coverage Accuracy of Confidence Intervals in Nonparametric Regression   总被引:2,自引:0,他引:2  
Point-wise confidence intervals for a nonparametric regression function with random design points are considered. The confidence intervals are those based on the traditional normal approximation and the empirical likelihood. Their coverage accuracy is assessed by developing the Edgeworth expansions for the coverage probabilities. It is shown that the empirical likelihood confidence intervals are Bartlett correctable.  相似文献   

19.
The necessary and sufficient conditions for the existence of simple incomplete block design (v, w; 4,2)-IPBDs are determined. As a consequence, the necessary and sufficient conditions for the embeddings of simple two-fold balanced incomplete block designs with block size 4 are also determined.  相似文献   

20.
The preconditioned iterative solvers for solving Sylvester tensor equations are considered in this paper.By fully exploiting the structure of the tensor equation,we propose a projection method based on the tensor format,which needs less flops and storage than the standard projection method.The structure of the coefficient matrices of the tensor equation is used to design the nearest Kronecker product(NKP) preconditioner,which is easy to construct and is able to accelerate the convergence of the iterative solver.Numerical experiments are presented to show good performance of the approaches.  相似文献   

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