自适应多波束形成的算法

论述了一种窄带和宽带多波束形成的算法,这种算法所依据的准则是在波束满足指向和振幅要求的约束条件下使阵列输出功率最小。对于 N 元阵列,可同时形成 N-1个独立波束。根据对约束条件的不同控制,利用这种算法可实现波束扫描,形成宽波束、实现干扰对消或旁瓣对消等。同时还给出了所述算法的计算机模拟结果,结果表明所述算法是很有效的。     

The Design And Analysis of a Mixture Experiment on Glass Durability

This paper discusses the statistical design and analysis of a non–standard constrained mixture experiment on glass durability (the components sum to 1, and there are non–trivial lower or upper bounds on components or combinations of them). It notes some of the difficulties which arose during the study, and shows how the aims and methods of the experiment changed during its execution.     

带包络约束的优化滤波器设计方法

对信道均衡、雷达或声纳脉冲压缩等应用领域中要求满足波形条件且使输出噪声增益最小化的滤波器设计问题进行了研究。用波形包络约束表达式和极值条件可以准确地描述滤波器的性能要求,从而将该设计问题转化为半无限二次凸规划问题进行分析。利用Lagrangian对偶理论和Carathéodory维度理论把半无限二次凸规划问题转化成等价的易于求解的有限维对偶优化问题,并给出了求解有限维对偶优化问题的迭代算法,设计实例表明了此方法的有效性。     

论语言适应论的语境生成观

语言适应论框架下的语境论是一种以适应性为核心的生成观,它认为语境不是给定的,而是一个动态的受限生成过程。这种生成观将语境的建构性、自组织性、受限性与涌现性的关系的认识,提出到一个新的理论层面,它具有三个显著特征:1."生成"是受限的;2.语境生成的"过程"重于生成的"结果";3."生成"是涌现的。     

Editorial

This paper uses the empirical characteristic function (ECF) procedure to estimate the parameters of mixtures of normal distributions. Since the characteristic function is uniformly bounded, the procedure gives estimates that are numerically stable. It is shown that, using Monte Carlo simulation, the finite sample properties of th ECF estimator are very good, even in the case where the popular maximum likelihood estimator fails to exist. An empirical application is illustrated using the monthl excess return of the Nyse value-weighted index.     

Methods for estimating proportions of convex combinations of normals using linear feature selection

Let X be a random n-vector whose density function is given by a mixtur.e of two density functions, h₁ and h₂ with unknown mixture proportions, Y₁ and Y₂ We assume that each of h₁ and h₂ is a convex combination of known multivariate normal density functions whose corresponding mixture proportions are also unknown. We present three numerically tractable methods for estimating Y₁ and Y₂ related to the technique of Guseman and Walton (1977), and based on the linear feature selection technique of Guseman, Peters and Walker (1975).     

Constrained nonparametric maximum likelihood estimation of stochastically ordered survivor functions

This paper considers estimators of survivor functions subject to a stochastic ordering constraint based on right censored data. We present the constrained nonparametric maximum likelihood estimator (C‐NPMLE) of the survivor functions in one‐and two‐sample settings where the survivor distributions could be discrete or continuous and discuss the non‐uniqueness of the estimators. We also present a computationally efficient algorithm to obtain the C‐NPMLE. To address the possibility of non‐uniqueness of the C‐NPMLE of $S_1(t)$ when $S_1(t)\le S_2(t)$ , we consider the maximum C‐NPMLE (MC‐NPMLE) of $S_1(t)$ . In the one‐sample case with arbitrary upper bound survivor function $S_2(t)$ , we present a novel and efficient algorithm for finding the MC‐NPMLE of $S_1(t)$ . Dykstra ( 1982 ) also considered constrained nonparametric maximum likelihood estimation for such problems, however, as we show, Dykstra's method has an error and does not always give the C‐NPMLE. We corrected this error and simulation shows improvement in efficiency compared to Dykstra's estimator. Confidence intervals based on bootstrap methods are proposed and consistency of the estimators is proved. Data from a study on larynx cancer are analysed to illustrate the method. The Canadian Journal of Statistics 40: 22–39; 2012 © 2012 Statistical Society of Canada     

多油品供给受限下多油库被动配送车辆路径问题研究

成品油供给不足将导致加油站油品订单无法完全满足,如何安排有限油品的合理配送对保障能源供给安全至关重要。为此,本文考虑有限供给下不同客户配送的优先次序,开展配送计划、车辆调度和路径优化等油品配送网络规划活动,对多油品供给受限情况下多油库被动配送车辆路径问题（Multiple Depot Vehicle Routing Problem,MDVRP）进行深入研究。首先,文章构建了考虑需求优先等级和配送成本的多油品多油库车辆路径规划多目标优化模型。其次,采用多目标粒子群优化算法（Multi-Objective Particle Swarm Optimization,MOPSO）对模型进行求解,以实现车辆高效调度和油品配送路径优化。最后,基于CNPC在青岛市部分油库和加油站点的数据信息,构建油品配送网络进行实证检验。算例结果显示,配送车辆路径经过优化后,生成Pareto非劣解集,配送成本显著降低,配送满足率明显提高,这也进一步验证了该模型及相关算法的可行性和有效性。     

广东农村成人教育发展研究

要增强农村的发展后劲,必须正视和提高人力资本存量,最快捷的办法是发展农村成人教育;广东农村成人教育发展现状喜忧参半,不能适应广东农村经济发展的要求。在分析制约广东农村成人教育发展因素的基础上,提出更新观念、城乡统等、创新教育的发展措施。     

Chance constrained optimization for targeted Internet advertising

We introduce a chance constrained optimization model for the fulfillment of guaranteed display Internet advertising campaigns. The proposed formulation for the allocation of display inventory takes into account the uncertainty of the supply of Internet viewers. We discuss and present theoretical and computational features of the model via Monte Carlo sampling and convex approximations. Theoretical upper and lower bounds are presented along with a numerical substantiation.