Development,construction, and use of pneumometric tubes for measurement of steam flow in the steam lines of PVG-1000 at NPP

A system for the direct measurement of steam flow in steam lines after a steam generator, which utilizes a special design of pneumometric tubes and a computing unit that accounts for variation in steam pressure, has been developed to improve the quality of water-level regulation in the steam generators of VVéR-1000 power-generating units in the stationary and transitional modes. The advantage of the pneumometric tubes consists in their structural simplicity, high erosion resistance, and absence of irrevocable losses during measurement of steam flow. A similar measurement system is used at foreign NPP. The measurement system in question has been placed in experimental service at the No. 3 unit of the Balakovo NPP, and has demonstrated its worthiness. This measurement system can also be used to determine steam flow in the steam lines of NPP units with VVéR-1000 and VVéR-440 reactors, and PBMK-1000 power-generating units. __________ Translated from élektricheskie Stantsii, No. 3, March 2007, pp. 23–26.     

低渗透砂岩油藏注CO

着重介绍了细管实验条件对最小混相压力实验确定方法测试结果的影响。通过数值模拟方法发现,当细管长度越长、细管直径越小、驱替速度越大、孔隙度越小,则得到的最小混相压力值也越小。另外,还讨论了油藏温度、注入气组成及原油的组成与性质对混相压力的影响情况。通过对比国内外注CO₂混相驱油藏与流体的条件,说明了中国原油很难实现CO₂混相的原因即地层温度高、地面油粘度大。建议开展降低最小混相压力技术及加强防止气体突破技术的研究,以解决注气过程中气体波及效率低的问题,实现较高的采收率。     

变风量空调系统

介绍了变风量空调系统（VAV系统）的特点、末端装置的型式以及最小送风量的确定方法，指出了VAV系统的研究重点和发展前景。     

Quantitative evaluation of generator power control effect of FACTS controllers for power system stabilization

The advancement of power electronics technologies has significantly developed the power system stabilizing controllers. Quantitative as well as qualitative evaluation of their effectiveness in power systems is a matter of great importance for the feasibility investigation of these apparatus. In this paper, the possible control region of FACTS controllers with series and/or shunt configuration in a single machine to infinite bus system is formulated in the powerangle curve with a set of algebraic equations. The effectiveness of TCPST (Thyristor‐Controlled Phase Shifting Transformer), SSSC (Static Synchronous Series Compensator), and TCSC (Thyristor‐Controlled Series Compensator) for the improvement of the transient stability is evaluated quantitatively as a numerical example. The correctness of the proposed method has been confirmed by analysis based on the electromagnetic transients simulation with a detailed system model. © 2001 Scripta Technica, Electr Eng Jpn, 138(3): 43–51, 2002     

分析离心油泵性能的新方法

提出一种利用已知泵性能曲线深入分析离心油泵性能的新方法。首先列出离心泵内部流动能量平衡关系式和离心泵基本方程并分别对其求导 ，根据实验数据，联立求解方程计算出滑移系数、水力损失系数、容积效率、水力效率和机 械效率等参数随叶片数的变化关系，深入研究了叶片数对性能的影响。结果表明，滑移系数随叶片数增加而增大；叶片数通过改变叶轮滑移系数和水力效率来影响泵的水力性能；降低叶轮圆盘摩擦损失是提高离心油泵性能的关键。     

F150交换机告警关联规则的研究

为了提高电信网络运营效率，降低维护成本，电信运营企业在网络告警管理系统中需要引入数据挖掘技术。本文主要研究利用数据挖掘技术来进行故障的管理，即对告警进行关联性分析，详细分析了告警序列数据的关联规则挖掘算法，并在南昌本地网F150交换机的告警数据库中予以实现，同时对实际挖掘结果进行分析和整理，推导出一些实用的关联规则。     

An IR study on ion-specific and solvent-specific swelling of poly(N-vinyl-2-pyrrolidone) gel

Swelling degrees of poly(N-vinyl-2-pyrrolidone) (PVP) gel were measured in aqueous salt solutions and in water/organic solvent mixtures to find marked ion- and solvent-specificities. In order to investigate any correlation of those specificities with hydration or solvation of PVP, IR spectra band of the CO group was monitored by means of ATR method both for PVP gel and the relevant solution systems. Dependence of the peak frequency on the swelling ratio suggested that hydration of PVP carbonyl group in deswollen gel systems is different from that in the corresponding solution systems. In the solution systems, PVP carbonyl band showed a high-wavenumber shift for deswollen systems, which can be well correlated with changes in water proton charge through ionic hydration and with Gutmann's acceptor number of organic solvents. In the deswollen gel systems, the CO band showed a low-wavenumber shift, suggesting a strong hydration or doubly hydrated state. This unexpected behavior was interpreted by assuming an intermolecular hydrogen bond of two carbonyl groups intermediated by water molecules.     

国产550MW水轮发电机用新材料和新工艺

介绍了二滩水电站 5 5 0MW机组发电机定转子绕组方面所采取的新结构、新工艺和新材料     

Spreading Codes Generator for Wireless CDMA Networks

The prime characteristic of spread spectrum modulated signals is that their bandwidth is greater than the information rate. In this way a redundancy is introduced that allows the severe levels of inteference inherent in the transmission of digital information over radio and satellite links to be overcome. Current spread spectrum applications are primarily in military communications; nevertheless, there is growing interest in this technique for third generation mobile radio networks (UMTS, FPLTS, etc.) with open discussion regarding the practicality of using a multiple access system based on spread spectrum techniques (CDMA). However, in order to support as many users in the same bandwidth as other multiple access techniques such as TDMA or FDMA, it is important how to generate large families of sequences that present low cross-correlation. The aim of this paper is to describe a spreading codes generator that can produce a large number of PN sequences with good properties of auto- and cross-correlation. Moreover, the codes generated shows high unpredictability and good statistical behaviour. This also allows the implementation of some features that are common on military networks such as message privacy (increasingly important in commercial networks) without additional cost. The structure presented shows itself to be advantageous for high speed generation of codes at a low cost, low power consumption (allowing longer life for batteries), small size and simplicity of implementation, essential ingredients for commercial equipment. Another attractive feature is its structural parallelism, useful in VLSI implementations. All of these features render it potentially suitable for the implementation of channel bandwidth sharing systems in future wireless personal communications networks.     

关于蒸汽疏水器规格尺寸选择的探讨

本文依据疏水器作用原理和实践经验对影响选择疏水器规格尺寸的主要因素进行了分析。提出:选择疏水器应排凝水量大,选择倍率适当,符合产品样本的最大、最小工作压力,准确确定其前后压力。