活性污泥数学模型入流组分测定及应用

阐述了活性污泥1号模型人流组分的分析方法，并用这些方法测定了西安市城市污水水质。实验结果表明测定方法操作简单、准确可靠，能为利用模型进行污水处理厂的设计、模拟及管理提供入流组分分析依据，     

Optical Splitting Trees for High-Precision Monocular Imaging

In this article, we consider the design of monocular multiview optical systems that form optical splitting trees, where the optical path topology takes the shape of a tree because of recursive beam splitting. Designing optical splitting trees is challenging when it requires many views with specific spectral properties. We introduce a manual design paradigm for optical splitting trees and a computer-assisted design tool to create efficient splitting-tree cameras. The tool accepts as input a specification for each view and a set of weights describing the user's relative affinity for efficiency, measurement accuracy, and economy. An optimizer then searches for a design that maximizes these weighted priorities. Our tool's output is a splitting-tree design that implements the input specification and an analysis of the efficiency of each root-to-leaf path. Automatically designed trees appear comparable to those designed by hand; we even show some cases where they are superior. With the help of the optimizer, the system demonstrates high dynamic range, focusing, matting, and hybrid imaging implemented on a single, reconfigurable camera containing eight sensors     

一种协调的科技文献分类方法

科技文献之间的相互引证关系反映了一种科学交流活动,显示了科学文献之间(甚至是学科之间)的内在联系,而通过追溯文献之间的这种关系,可以改善和提高传统的基于内容的科技文献的分类的方法。论文利用有相互引证关系,有同引关系,以及有耦合关系的两篇文献一般是属于同一类的这一特点,提出了文献之间的引用相似度,同引相似度,耦合相似度这三个概念,再利用这三个概念生成了文献之间的“结构相似度”,并将它用于K-NN分类法中得出一种基于结构的分类法。最后,论文将这种基于结构的分类法和基于内容的NaveBayes分类法结合起来提出了一种新的协调分类法。     

Low-cost and reliable mutual anonymity protocols in peer-to-peer networks

We present several protocols to achieve mutual communication anonymity between an information requester and a provider in a P2P information-sharing environment, such that neither the requester nor the provider can identify each other, and no other peers can identify the two communicating parties with certainty. Most existing solutions achieve mutual anonymity in pure P2P systems without any trusted central controls. Compared with two such representative ones, our protocols improve efficiency in two different ways. First, utilizing trusted third parties and aiming at both reliability and low-cost, we propose a group of mutual anonymity protocols. We show that with some limited central support, our protocols can accomplish the goals of anonymity, efficiency, and reliability. Second, we propose a mutual anonymity protocol which relies solely on self-organizations among peers without any trusted central controls. In this protocol, the returning path can be shorter than the requesting path. This protocol does not need to broadcast the requested file back to the requester so that the bandwidth is saved and efficiency is improved. In addition, this protocol does not need special nodes to keep indices of sharing files, thus eliminating the index maintenance overhead and the potential for inconsistency between index records and peer file contents. We have evaluated our techniques in a browser-sharing environment. We show that the average increase in response time caused by our protocols is negligible, and these protocols show advantages over existing protocols in a P2P system.     

The thermal behavior of mechanically activated galena by thermogravimetry analysis

The thermal decompositions of mechanically activated and nonactivated galenas were studied by thermogravimetry analysis (TGA) at the heating rate of 10 K min⁻¹ in argon. Results indicate that the initial temperature of thermal decomposition (abbreviated as T _di) in the TGA curves for different galenas decreases gradually with increased grinding time. The specific granulometric surface area (S _G), the structural disorder, and the content of elemental sulfur of mechanically activated galenas were analyzed by an X-ray diffraction (XRD) laser particle-size analyzer, XRD analysis, and the gravimetric method, respectively, which shows that the specific granulometric surface area of mechanically activated galenas remains almost constant after a certain grinding time, but the lattice distortions (ε) rise, the crystallite sizes (D) decrease, and the elemental sulfur contents of mechanically activated galenas increase with increased grinding time. The results imply that the decrease of the initial temperature of thermal decomposition in the TGA curves for mechanically activated galenas is mainly caused by the increase of lattice distortions, and the formation of new dangling bonds resulted from the production of elemental sulfur of mechanically activated galenas with increased grinding time. Finally, the differences in the thermal-decomposition reactivity between nonactivated and mechanically activated galenas were also discussed.     

Heat transfer of a row of three butane/air flame jets impinging on a flat plate

Experiments were performed to investigate the heat transfer characteristics of a row of three premixed, laminar, butane/air flame jets impinging on a water-cooled flat plate. The between-jet interference was found to reduce the heat transfer rate in the jet-to-jet interacting zone due to the depressed combustion. The interference became stronger when the jet-to-jet spacing and/or the nozzle-to-plate distance were/was small. The positive pressure existed in the between-jet interacting zone caused the asymmetric flame and heat transfer distribution of the side jet. The meeting point of the spreading wall jets of the central and the side jets did not occur at the midpoint of the neighboring jets, but at a location shifted slightly outwards. The maximum local heat flux and the maximum area-averaged heat flux occurred at a moderate nozzle-to-plate distance of 5d with a moderate jet-to-jet spacing of 5d. The lowest area-averaged heat flux was produced when both the jet-to-jet spacing and the nozzle-to-plate distance were small. Comparing with a single jet under the same experimental conditions, the heat transfer rates in both the stagnation point and the maximum heat transfer point were shown to be enhanced in a row of three-jet-impingement system. The present study provided detailed information on the heat transfer characteristics of a row of three in-line impinging flame jets, which had rarely been reported in previous study.     

裂缝性潜山储层地震描述技术

裂缝是潜山油气藏的重要储集层 ,潜山的油气产出与裂缝的发育情况密切相关 ,因此 ,对裂缝发育控制因素和裂缝发育规律进行了分析和探讨。尽管单条裂缝在地震资料上难以识别 ,但是裂缝带在地震资料上有其特征。描述了裂缝储层的地球物理特征 ,并利用测井约束反演技术、吸收系数技术、地震相分类和相干分析技术对潜山储层进行预测。通过在车古 2 0 1潜山的应用实例分析 ,说明以上 4种储层描述技术比较有效     

三维数字城市的建设

提出了一种应用三维技术和虚拟现实交互技术来构建三维数字城市的设计思想和实施方案，探讨了具体实现三维数字城市系统而积累的实践经验，介绍了综合运用3DS MAX、AUTOCAD和CULT3D对“实例”进行制作的具体方法和步骤，并给出了部分制作结果。结果表明该系统获得了较好的实时浏览和交互浏览功能，且有良好的视觉效果。     

计算机辅助施工放样设计与应用

应用数学理论知识和CAD技术对施工图进行建模,从而获得准确的放样参数指导施工,并结合工程实例对计算机辅助施工放样过程进行了具体的介绍。