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81.
This paper presents a valve-regulated lead acid (VRLA) battery reserve life estimation scheme. The scheme is adaptive in both type and frequency of involvement. The scheme is based on capacity trending with the support of a number of state-of-health (SOH) indicators. These SOH indicators include accumulated thermal stress, float voltage, and indicators acquired from the start-of-discharge (coup de fouet) region. An implementation test case is given, indicating that the scheme is capable of providing an accurate estimation of reserve life long before the end of life. Furthermore, the estimation accuracy improves as the end of battery life approaches. 相似文献
82.
Many approaches have been proposed to enhance software productivity and reliability. These approaches typically fall into three categories: the engineering approach, the formal approach and the knowledge-based approach. But the optimal gain in software productivity cannot be obtained if one relies on only one of these approaches. This paper describes the work in knowledge-based software engineering conducted by the authors for the past 10 years. The final goal of the research is to develop a paradigm for software engineering which integrates the three approaches mentioned above. A knowledge-based tool which can support the whole process of software development is provided in this paper. 相似文献
83.
S.N. Al-Refaie H.S.B. Elayyan 《Science, Measurement & Technology, IET》2007,1(3):133-137
The dispersion of potassium niobate (KNbO3) ceramics is analysed using the multiple-arc approach. This has revealed a high frequency arc that is unattainable by the Cole-Cole single arc analysis. The temperature dependence of the new arc is derived through the spread parameter of the relaxation distribution and interpreted in terms of the ferroelectric property of the KNbO3 ceramics. It is shown that the overall dispersion behaviour of the ceramics is mainly due to the existence of two distinctly different polarisation mechanisms. The arc approach has also provided an effective tool for network simulation of dispersion whereby the ceramics are modelled by nine parallel R-C branches over the frequency range 102-105 Hz used 相似文献
84.
LaNiO3 was synthesized by sol-gel method in which lanthanum nitrate and nickel nitrate were used as start materials and citric acid was used as complex for gel formation.The precursor was dried and subsequently heated at elevated temperature to form the desired product.XRD analysis shows that pure LaNiO3 was synthesized.Electrical conductivity and electrochemical performance of the material were tested.The electrical conductivity decreases from 34.5that there are current peaks in the curve, which is the evidence of the electrochemical activity of LaNiO3. 相似文献
85.
86.
Colour is the most widely used attribute in image retrieval and object recognition. A technique known as histogram intersection has been widely studied and is considered to be effective for color‐image indexing. The key issue of this algorithm is the selection of an appropriate color space and optimal quantization of the selected color space. The goal of this article is to measure the model performance in predicting human judgment in similarity measurement for various images, to explore the capability of the model with a wide set of color spaces, and to find the optimal quantization of the selected color spaces. Six color spaces and twelve quantization levels are involved in evaluating the performance of histogram intersection. The categorical judgment and rank order experiments were conducted to measure image similarity. The CIELAB color space was found to perform at least as good as or better than the other color spaces tested, and the ability to predict image similarity increased with the number of bins used in the histograms, for up to 512 bins (8 per channel). With more than 512 bins, further improvement was negligible for the image datasets used in this study. © 2005 Wiley Periodicals, Inc. Col Res Appl, 30, 265–274, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/col.20122 相似文献
87.
W. L. Siew F. C. H. Oh A. S. H. Ong 《Journal of the American Oil Chemists' Society》1985,62(6):1036-1039
Some of the factors affecting cloud point determination of palm oleins are described. These are the type of container used, method of stirring, rate of stirring and bath temperature. The repeatability and reproducibility standard deviations of the method are determined from collaborative trials. Recommendations for the test are made to reduce the large variations among laboratories. 相似文献
88.
89.
The biological decolorization of two industrial, spent textile reactive dyebaths was investigated using a suspended-growth, halophilic mixed culture fed with glucose. Dyebath I contained mainly Reactive Blue 19 (RB19), an anthraquinone dye, whereas dyebath II contained mainly Reactive Blue 21 (RB21), a phthalocyanine dye. Batch assays under anaerobic conditions with the two neutralized dyebaths resulted in 87 and 37% extent of decolorization for dyebaths I and II, respectively. The rate of glucose utilization and the extent of acetate production were impacted in the presence of each dyebath as compared to the control culture. However, dyebath decolorization occurred despite moderate culture inhibition. Reuse of a biologically renovated RB19-containing dyebath in the dyeing process resulted in reproducible but not identical cotton fabric shades as compared to a standard dyeing (i.e., control) using fresh water. This difference is attributed to a variable degree of RB19 aggregation during the dyeing process and is not related to the efficiency of the biodecolorization process. Further improvement of the redyeing efficiency will lead to the development of an in-plant, closed-loop decolorization system resulting in significant water conservation and minimization of textile pollutants such as salt and dyes. 相似文献
90.
Sure System 2000, a fault-tolerant computer that couples multiprocessors to offer low-priced, high-performance systems that deal effectively with faults and failures, is presented. The architecture is based on the local redundancy technique, ensuring that no hardware or software fault can cause a system crash. Software errors can be fixed, and hardware can be replaced, upgraded, or added dynamically. Existing fault-tolerant computers are briefly reviewed, and the logic hardware system configuration of the Sure System 2000 is described. The multiprocessor and I/O architecture are examined. The SXO Sure System 2000 expandable operating system is described 相似文献