多输入单输出逆高斯分布流域汇流模型

本文将逆高斯分布应用于由水库和区间组成的复杂的流域汇流系统，并建立了多输入单输出逆高斯单位线模型。讨论了模型参数的估计方法，并对沾益流域的雨洪资料进行了实例分析。     

45钢表面超音速电弧喷涂Ti-Al涂层的组织与性能研究

采用自行开发研制的超音速电弧喷设备，在45钢表面制成了钛铝合金复合涂层。并利用金相显微镜、X射线衍射仪、扫描电镜、电子探针，对涂层的成分、相结构、显微组织及其结合强度、显微硬度进行了研究。结果表明，利用超音速电弧喷涂设备，可以在45钢表面形成 度高、孔隙率低，结合强度较好和硬度高的Ti-Al合金涂层。     

超低密度硬胶极压型油包水乳化钻井液在广安002-H9井的应用

在超低密度钻井液的使用方面，传统的油基钻井液和油包水钻井液存在易着火、安全性差的问题，而最近使用的美国3M公司的中空玻璃微珠聚磺钻井液又存在固控困难、钻井液费用很高等难题。为此，从选择合适的润湿反转剂和阻燃剂入手，在室内对获得的超低密度硬胶极压型油包水乳化钻井液成果配方进行了全面评价，并应用在广安002 H9井水平段欠平衡钻井中取得了良好效果。室内研究与现场应用表明，超低密度硬胶极压型油包水乳化钻井液能够很好地满足广安构造水平井段欠平衡钻井的需要。该钻井液体系具有防塌、润滑、携砂能力强，密度容易控制，钻井液单位成本合理并可重复使用，安全性好等显著特点，适合在类似广安构造的水平井段中推广应用。     

Boosting nitrification by membrane-attached biofilm.

Nitrification is a key step for reliable biological nitrogen removal. In order to enhance nitrification in the activated sludge (AS) process, membrane-attached biofilm (MAB) was incorporated in a conventional activated sludge tank. Simultaneous organic carbon removal and nitrification of the MAB incorporated activated sludge (AS + MAB) process was investigated with continuous wastewater treatment. The effluent TOC concentration of AS and the AS + MAB processes were about 6.3 mg/L and 7.9 mg/L, respectively. The TOC removal efficiency of both AS and AS + MAB were above 95% during the wastewater treatment, indicating excellent organic carbon removal performance in both processes. Little nitrification occurred in the AS process. On the contrary, successful nitrification was obtained with the AS + MAB process with nitrification efficiency of about 90%. The volumetric and surface nitrification rates were about 0.14 g/Ld and 6.5 g/m2d, respectively. The results clearly demonstrated that nitrification in the conventional AS process was boosted by MAB. Furthermore, the microfaunal population in the AS + MAB process was different from that in the AS process. The high concentration of rotifers in the AS + MAB process was expected to decrease the generation of excess sludge in the process.     

Optimal algorithms for adjacent side routing

We consider the switchbox routing problem of two-terminal nets in the case when all thek nets lie on two adjacent sides of the rectangle. Our routing model is the standard two-layer model. We develop an optimal algorithm that routes all the nets whenever a routing exists. The routing obtained uses the fewest possible number of vias. A more general version of this problem (adjacent staircase) is also optimally solved.This research was supported in part by NSA Contract No. MDA-904-85H-0015, NSF Grant No. DCR-86-00378, and by NSF Engineering Research Centers Program NSFD CDR 88003012.     

Minimum-energy multicast in mobile ad hoc networks using network coding

The minimum energy required to transmit one bit of information through a network characterizes the most economical way to communicate in a network. In this paper, we show that, under a layered model of wireless networks, the minimum energy-per-bit for multicasting in a mobile ad hoc network can be found by a linear program; the minimum energy-per-bit can be attained by performing network coding. Compared with conventional routing solutions, network coding not only allows a potentially lower energy-per-bit to be achieved, but also enables the optimal solution to be found in polynomial time, in sharp contrast with the NP-hardness of constructing the minimum-energy multicast tree as the optimal routing solution. We further show that the minimum energy multicast formulation is equivalent to a cost minimization with linear edge-based pricing, where the edge prices are the energy-per-bits of the corresponding physical broadcast links. This paper also investigates minimum energy multicasting with routing. Due to the linearity of the pricing scheme, the minimum energy-per-bit for routing is achievable by using a single distribution tree. A characterization of the admissible rate region for routing with a single tree is presented. The minimum energy-per-bit for multicasting with routing is found by an integer linear program. We show that the relaxation of this integer linear program, studied earlier in the Steiner tree literature, can now be interpreted as the optimization for minimum energy multicasting with network coding. In short, this paper presents a unifying study of minimum energy multicasting with network coding and routing.     

对水利经济发展策略的探讨

文章从发展水利经济的必要性入手,列举发展水利经济中存在的种种问题,提出发展水利经济可以采取相关的政策措施、工程措施和管理措施。     

APT（STLRI）—1.78型单模光纤（缆）连接器简介

利用引进的制造技术和设备,制作出了 APT(STLRI)—1.78型系列化光纤连接器。     

Low-thermal expansion polycrystalline tantalum tungstate ceramics

The synthesis of thermal-shock-resistant materials from the system Ta₂O₅WO₃ was investigated. Ta₂WO₈ had a very low unit-cell thermal expansion coefficient (+0.5 X 10^–6° C^–1). Ta₃₀W₂O₈₁ also had a relatively low coefficient (+4.0 X 10^–6 ° C^–1) and a thermal durability over 1600° C. The thermal expansion curves of these polycrystalline ceramics were lowered because of microcracks caused by the large thermal expansion anisotropy of the crystal axes and were accompanied by hysteresis loops. The densification of Ta₂WO₈ ceramic was promoted by the addition of some metal oxides, and the strong ceramic of Ta₃₀W₂O₈₁ was obtained by controlling grain growth.