Hyperspaces of Normed Linear Spaces with the Attouch–Wets Topology

Let Cld _AW (X) be the hyperspace of nonempty closed subsets of a normed linear space X with the Attouch–Wets topology. It is shown that the space Cld _AW (X) and its various subspaces are AR's. Moreover, if X is an infinite-dimensional Banach space with weight w(X) then Cld _AW (X) is homeomorphic to a Hilbert space with weight 2 ^w(X).     

111In–L–LDL and 153Gd–L–LDL as radiotracers for detection of AR4‐2J rat pancreatic tumors

Pancreatic cancer has an extremely poor prognosis, due, in part, to lack of methods for early diagnosis. The present study was designed to evaluate the potential of labeling low‐density lipoprotein (LDL) with a radionuclide using a lipid chelating agent, bis(stearylamide) of diethylenetriaminepentaacetic acid (L), to detect pancreatic tumors by gamma‐scintigraphy. Previous studies indicated that the difficulty of visualization of pancreatic tumors was due to their poor vascularization. This study compares the ability of two radiotracers, ¹¹¹In–L–LDL and ¹⁵³Gd–L–LDL to target highly vascularized rat pancreatic tumors (AR4‐2J) implanted in nude mice. Biodistribution studies showed that the tumor uptake of ¹¹¹In–L–LDL and ¹⁵³Gd–L–LDL tracers was twofold and fivefold higher respectively than with the controls (¹¹¹In citrate and ¹⁵³Gd citrate respectively). These tracers would thus be suitable for scintigraphic imaging. We show here that LDL could be employed as a delivery system for tracers such as ¹¹¹In or ¹⁵³Gd when these two radionuclides are complexed by a lipid‐chelating anchor, and that ¹¹¹In–L–LDL and ¹⁵³Gd–L–LDL enabled better visualization of the pancreatic tumor tissues, with a better result with ¹⁵³Gd–L–LDL. Copyright © 2004 John Wiley & Sons, Ltd.     

Regression quantiles for unstable autoregressive models

This paper investigates regression quantiles (RQ) for unstable autoregressive models. The uniform Bahadur representation of the RQ process is obtained. The joint asymptotic distribution of the RQ process is derived in a unified manner for all types of characteristic roots on or outside the unit circle. It involves stochastic integrals in terms of a sequence of independent and identically distributed multivariate Brownian motions with correlated components. The related L-estimator is also discussed. The asymptotic distributions of the RQ and the L-estimator corresponding to the nonstationary componentwise arguments can be transformed into a function of a normal random variable and a sequence of i.i.d. univariate Brownian motions. This is different from the analysis based on the LSE in the literature. As an auxiliary theorem, a weak convergence of a randomly weighted residual empirical process to the stochastic integral of a Kiefer process is established. The results obtained in this paper provide an asymptotic theory for nonstationary time series processes, which can be used to construct robust unit root tests.     

Chapter 15 DEA/AR analysis of the 1988–1989 performance of the Nanjing textiles corporation

This article employs new data envelopment analysis/assurance region (DEA/AR) methods to evaluate the efficiency of the 35 textile factories of the Nanjing Textiles Corporation (NTC), Nanjing, China. The returns to scale (RTS) of these factories were studied without assuming that the optimal DEA solutions were unique. All DMUs are identified with pointsE (Extreme Efficient),E (Efficient but not an extreme point) andF (Frontier but not efficient). We then further identify the nonfrontier DMUs with pointsNE, NE andNF according to whether they are projected onto a point inE, E, orF en route to evaluating their performances. All of the inefficient factories were in classNF and had unique optimal primal-dual solution pairs. Consequently, the solution pairs satisfy the strong complementary slackness condition (SCSC). Application of cone-ratio (CR) ARs reduced significantly the number of factories in classE, and showed that some AR-efficient factories were more flexible in adopting the mixture of central planning and market economies that China currently is trying to use. Also, linked-cone (LC) ARs were applied to measure maximum and minimum profit ratios. The SCSC multiplier space approach was utilized to analyze the sensitivity of the efficiency results to potential errors in the data with and without ARs. The results in this article suggest that collective units had a better performance than state-owned units in the two consecutive years analyzed.This paper was written while the author was at the School of Economics and Management, Southeast University, Nanjing 210018, P.R. China.     

一种非平稳随机信号模型的时变参数估计算法性能研究

采用递推最小二乘算法求解非平稳随机信号模型的时变参数。该方法的主要特点是计算量小，占用存贮空间少，没有矩阵求逆的问题。应用该方法的对分段线性调频信号、多个线性调频信号及非线性调频信号进行分析，比较了不同基时间函数的选取对时变参数估计的影响。     

表面粗糙度的综合评定及混合谱模型

采用自回归谱分析结合改进周期图检验的方法，建立表面粗糙度的混合谱模型，以分离其中表现为离散谱的确定性谐波成分和表现为连续谱的随机性成分，并在此基础上提出综合评定表面粗糙度各种参数的方法，同时对AR模型的阶数与谐波成分识别给出较有效的经验判定方法．     

全球参考站网窄巷非校准相位延迟

窄巷非校准相位延迟（UPD）产品的质量和可用性是影响精密单点定位模糊度固定（PPPAR）效率的重要因素.采用全球108个国际GPS服务（International GPS Service,IGS）测站观测数据,计算了基于全球参考站网的窄巷UPD产品,分析了窄巷UPD产品的变化特性,其单日变化量最大可达0.6周.通过分析UPD改正后的模糊度残差,论证了UPD产品和用户端模糊度均受到因未被恰当模型化而造成的残余误差的影响,且UPD的时变特性与各参考站残余系统误差有关.最后,采用4个用户站进行PPPAR实验分析UPD产品的可用性,以模糊度固定失败率、固定错误率和首次固定时间为评估指标,结果表明,全球参考站网窄巷UPD产品的最佳使用时限不大于30 min.     

VR/AR在文化旅游与影视中的应用创新 与趋势

 虚拟现实/增强现实（VR/AR）技术是一种改变大众生活方式的新兴科学技术,对大众文化领域将能够产生重大影响。本文分析VR/AR在文化旅游与影视领域的支撑技术及其演进、融合中的应用创新,研究其发展及对传媒文化产业的影响,探讨未来该领域的发展趋势。     

供应方信息共享对销售商绩效的影响

为了加强供应链的协调,研究了共享供应方的供货信息对销售商绩效的影响.在只有1个销售商和制造商的2层供应链系统中,当市场需求为AR(1)模式时,建立了及时共享制造商的供货信息时销售商的库存水平和运行成本的数学模型,讨论了在信息共享和不共享时,在订货至S水平的原则下,销售商不同的订货决策表达式,解析分析表明,共享供应方的信息对销售商在平均库存下降和运营成本节约两方面都有较大的价值.     

Low-Complexity Alternatives to the Optimal Linear Coding Scheme for Transmitting ARMA Sources

In the era of the Internet of Things, there are many applications where numerous devices are deployed to acquire information and send it to analyse the data and make informed decisions. In these applications, the power consumption and price of the devices are often an issue. In this work, analog coding schemes are considered, so that an ADC is not needed, allowing the size and power consumption of the devices to be reduced. In addition, linear and DFT-based transmission schemes are proposed, so that the complexity of the operations involved is lowered, thus reducing the requirements in terms of processing capacity and the price of the hardware. The proposed schemes are proved to be asymptotically optimal among the linear ones for WSS, MA, AR and ARMA sources.