徐州市造纸工业水污染综合治理的产业政策

概述了徐州市造纸工业的现状,指出了当前徐州市造纸企业存在的问题,并对徐州市造纸工业所面临的形势进行了分析,最后从行政角度研究了适合徐州市造纸企业水污染综合治理的产业政策.     

浅谈做好螺丝湾水电站施工质量,工期,投资控制的几项措施

螺丝湾水电站作为云南省电力局（ 集团公司） 、迪庆州、省投资公司三方合资建设的电站，是迪庆藏族自治州自建国以来投资最大的一个建设项目，它的建成，开创了滇西北水电资源多方合资开发的先例，有其特殊的经济和政治意义。本文结合螺丝湾水电站建设的实际情况，论述了在市场经济条件下做好螺丝湾电站建设中“三控制”的几项措施     

Performance of in-call buffer/window allocation schemes for short intermittent file transfers over broadband packet networks

While static open loop rate controls may be adequate for handling continuous bit rate (CBR) traffic, relatively smooth data traffic, and relatively low speed bursty data traffic over broadband integrated networks, high speed bursty data sources need more dynamic controls. Burst level resource allocation is one such dynamic control. Potential benefits and other issues for burst level resource parameter negotiations for bursty data traffic over high speed wide area packet networks have been discussed earlier.^1–6 A detailed analysis of an adaptive buffer/window negotiation scheme for long file transfers using these concepts is presented in Reference 1. In this paper we discuss two burst level buffer/window negotiation schemes for short intermittent file transfers, focusing on the specific needs of such traffic streams. We develop closed network of queues models to reflect the behaviour of the proposed schemes. These models, while being simple, capture essential details of the control schemes. Under fairly general assumptions, the resulting network of queues is of product form and can be analysed using the mean value analysis. We use such an analysis to compare the proposed schemes and to determine appropriate sizes of trunk buffers to achieve the desired balance between bandwidth utilization and file transfer delay. The effects of other parameters on the performance of these schemes as well as on the buffer sizing rules are also discussed. Burst level (in-call) parameter negotiation may be carried out by the end system with the network elements or by an interface system (access controller) with the broadband network elements. We discuss implications of this location as well as the needed protocol features. Finally, the service discrimination capabilities desired at the trunk controllers in switching nodes are briefly discussed.     

精密深孔表面环状硬挤条纹的产生机理与控制

本文建立了不同条件下环状硬挤条纹的生成模型,详细分析了其产生机理.用理论解析和试验验证了所建模型的可靠性,最后提出了控制其产生的方法.     

Treeview控件构建VFP数据库字段树型目录

将ActiveX控件应用于Visual FoxPro中的一个实例。利用Comctl32.ocx文件中的TreeView控件,将VFP数据库字段构建出具有Windows文件夹分层列表展开的风格。使数据库字段选择既方便又美观。该程序可将任意VFP数据库中能被有效地分层显示的字段任意字段构建树型目录,也可稍加修改筛选不同类型的或条件的字段来构建树型目录。该实例具有一定的实用性,可根据需要将其嵌入自编的应用系统中,使自己的作品看起来更美观也更专业。     

HIGHER ORDER MOMENTS OF SAMPLE AUTOCOVARIANCES AND SAMPLE AUTOCORRELATIONS FROM AN INDEPENDENT TIME SERIES

Abstract. Given length- n sampled time series, generated by an independent distributed process, in this paper we treat the problem of determining the greatest order, in n , that moments of the sample autocovariances and sample autocorrelations can attain. For the sample autocovariance moments, we achieve quite general results; but, for the autocorrelation moments, we restrict study to Gaussian white noise (normal, independent and identically distributed). Our main theorem relates to the cross-moments of the non-centred sample autocovariances, but we also establish a relation between these and the corresponding moments for the centred sample autocovariances.     

Modeling for soft sensor systems and parameters updating online

Soft sensor technology is an important means to estimate important process variables in real-time. Modeling for soft sensor system is the core of this technology. Most nonlinear dynamic modeling methods integrate the processes of building the dynamic and static relationships between secondary and primary variables, which limits the estimation accuracy for primary variables. To avoid the problem, a kind of soft sensor model consisting of a dynamic model in cascade with a static one is proposed. The model identification and update online are conducted in substep way. In order to improve the model update efficiency, two improved Gauss–Newton recursive algorithms, which avoid nonsingular covariance matrix, are proposed for time-invariant and time-variant soft sensor systems. The uniform convergence for dynamic model parameter and the existence of estimation deviations for static model parameters are proved for time-invariant soft sensor system. The parameters of time-variant soft sensor system would be boundedly convergent. Case study confirms that, on the basis of the proposed model and recursive algorithms, the dynamic and static characteristics of soft sensor system can be described efficiently, and the primary variables are ensured to be estimated accurately.     

Automatic learners with feedback queries

Automatic classes are classes of languages for which a finite automaton can decide whether a given element is in a set given by its index. The present work studies the learnability of automatic families by automatic learners which, in each round, output a hypothesis and update a long-term memory, depending on the input datum, via an automatic function. Many variants of automatic learners are investigated: where the long-term memory is restricted to be the current hypothesis whenever this exists, cannot be of length larger than the length of the longest datum seen, or has to consist of a constant number of examples seen so far. Learnability is also studied with respect to queries which reveal information about past data or past computation history; the number of queries per round is bounded by a constant.     

基于dsPIC30F的恒流电子负载设计

设计了一种对33V锂电池进行最大5A恒流放电的电子负载。该电子负载以dsPIC30F6014A单片机为核心控制器,闭环控制MOSFET恒流放电,并以热能的方式消耗电能。锰铜电阻和仪用运算放大器AD623构成电流采样电路。测试结果显示,系统的相对误差低于6‰。