The Michigan benchmark: towards XML query performance diagnostics

We propose a micro-benchmark for XML data management to aid engineers in designing improved XML processing engines. This benchmark is inherently different from application-level benchmarks, which are designed to help users choose between alternative products. We primarily attempt to capture the rich variety of data structures and distributions possible in XML, and to isolate their effects, without imitating any particular application. The benchmark specifies a single data set against which carefully specified queries can be used to evaluate system performance for XML data with various characteristics.     

管内材料高温放气性能的测试及应用研究

管内材料放气性能的优劣直接影响着整管的性能和寿命.本文简介了测试管内材料高温放气性能的原理、装置和方法.文中列举的几项应用实例表明,本项测试结果对产品质量控制、工艺技术改进和材料进厂检验及国产化攻关都具有指导意义.     

广西天等贫氧化锰矿石的选矿试验研究

天等锰矿石属高硅、低磷贫氧化锰矿石，矿物结晶粒度微细。选矿试验中进行了洗矿、强磁和重选流程研究，试验结果表明，洗矿效果较好，当原矿含锰１６．８５％，经一段洗矿后，可获得含锰２９．７７％，锰回收率为８６．２７％的锰净矿。     

Ni_(2.5)Mo_6S_(6.7)在有机电解液中的充放电特性

利用循环伏安法、交流阻抗法和充放电曲线等方法测定了Ni_(2.5)Mo_6S_(6.7)电极在1M LiClO_4,PC DME(1:1)有机电解质溶液中的可充电性。结果表明,该材料具有高的可充电性,有可能用作二次锂电池的正极材料。     

渤中28－1（BZ28－1）油田N6H水平井动态分析

本文以渤中２８－１（ＢＺ２８－１）油田Ｎ６Ｈ水平井为例，从多方面对该井的动态和产能变化进行了系统分析，所用的方法对水平井动态分析有一定的指导意义。     

Wavelet based Denial-of-Service detection

Network Denial-of-Service (DoS) attacks that disable network services by flooding them with spurious packets are on the rise. Criminals with large networks (botnets) of compromised nodes (zombies) use the threat of DoS attacks to extort legitimate companies. To fight these threats and ensure network reliability, early detection of these attacks is critical. Many methods have been developed with limited success to date. This paper presents an approach that identifies change points in the time series of network packet arrival rates. The proposed process has two stages: (i) statistical analysis that finds the rate of increase of network traffic, and (ii) wavelet analysis of the network statistics that quickly detects the sudden increases in packet arrival rates characteristic of botnet attacks.Most intrusion detections are tested using data sets from special security testing configurations, which leads to unacceptable false positive rates being found when they are used in the real world. We test our approach using data from both network simulations and a large operational network. The true and false positive detection rates are determined for both data sets, and receiver operating curves use these rates to find optimal parameters for our approach. Evaluation using operational data proves the effectiveness of our approach.     

房柱法在斗南锰矿缓倾斜极薄矿体的试采

本文介绍了房柱法在斗南锰矿缓倾斜极薄矿体(厚度小于1.2m)中的试验情况。经试采证明,该方法是回采缓倾斜极薄矿体的一种有效方法。采场生产能力可达48t/d,矿房回采率为87.1％,矿块回采率为80.4％,废石混入率为9.3％。采用了预裂爆破、松动爆破和抛掷爆破技术,对减少粉矿以及矿石的贫化和损失,起到了很好的作用。     

空调表冷器性能微机测试系统设计与软件开发

介绍了一套用于空调表冷器性能测试的试验装置及配套软件，重点叙述了系统的总体构成、程序的设计思想以及数据采样和处理等功能模块。微机测试技术以及配套软件的使用大大减少了测试人员的工作量，并在一定程度上提高了测试的精度。     

Electrochemical improvement of low-temperature petroleum cokes by chemical oxidation with H2O2 for their use as anodes in lithium ion batteries

The electrochemical performance of non-graphitized petroleum cokes has been improved by mild oxidation using hydrogen peroxide, a procedure used for the first time in these materials. For this purpose, various carbonisation temperatures and H₂O₂ treatments were tested. For low sulfur content cokes, the aqueous oxidative treatment significantly increases the capacity values above 372 mAh/g during the first cycles. In contrast, cokes with a sulfur content of ca. 5%, did not shown a real improvement. The former results have been interpreted in terms of an effective oxidation of the particles surface, which removes unorganized carbon, where lithium can be irreversibly trapped. Moreover, a stable and less resistive passivating layer grows during the first discharge of lithium, as revealed by impedance spectroscopy. Therefore, chemical procedures, as mild oxidation, open an interesting field of research for the improvement of disordered carbons as anode materials in lithium ion batteries.     

The thermodynamic performance of a new solution cycle in double absorption heat transformer using water/lithium bromide as the working fluids

In this paper, a new solution cycle in the double absorption heat transformer is presented and the thermodynamic performance of this new cycle is simulated based on the thermodynamic properties of aqueous solution of lithium bromide. The results show that this new cycle is superior to the cycle being studied by some researchers. This new solution cycle has a wider range of operation in which the system maintains the high value of COP and has larger temperature lifts and operation stability. The relationship between the absorber and the absorbing evaporator is more independent and this makes the operation and control of the system more easier.