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101.
102.
Use of the logic programming language PROLOG assists in tracking functional relationships through complex networks to ensure that all products receive a security classification consistent with the operative security model. The language also permits computing work factors for data products. In some cases, these work factors may modify the levels of protection required.  相似文献   
103.
It is currently thought in the knowledge-based systems (KBS) domain that sophisticated tools are necessary for helping an expert with the difficult task of knowledge acquisition. The problem of detecting inconsistencies is especially crucial. The risk of inconsistencies increases with the size of the knowledge base; for large knowledge bases, detecting inconsistencies "by hand" or even by a superficial survey of the knowledge base is impossible. Indeed, most inconsistencies are due to the interaction between several rules via often deep deductions. In this paper, we first state the problem and define our approach in the framework of classical logic. We then describe a complete method to prove the consistency (or the inconsistency) of knowledge bases that we have implemented in the COVADIS system.  相似文献   
104.
We here report on the stability and catalytic activity of new indenylidene‐Schiff base‐ruthenium complexes 3a – f through representative cross‐metathesis (CM) and ring‐closing metathesis (RCM) reactions. Excellent activity of the new complexes was found for the two selected RCM reactions; prominent conversion was obtained compared to the commercial Hoveyda–Grubbs catalyst 2 . Moreover, excellent results were obtained for a standard CM reaction. Higher conversions were achieved with one of the indenylidene catalysts compared with Hoveyda–Grubbs catalyst. Unexpectedly, an isomerization reaction was observed during the CM reaction of allylbenzene. To the best of our knowledge, isomerization reactions in this model CM reaction in closed systems have never been described using first generation catalysts, including the Hoveyda–Grubbs catalyst. The first model CM reactions as well as the RCM reactions have been monitored using 1H NMR. The course of the CM reaction of 3‐phenylprop‐1‐ene ( 8 ) and cis‐1,4‐diacetoxybut‐2‐ene ( 9 ) was monitored by GC. The isomerization reaction was studied by means of GC‐mass spectrometry and in situ IR spectroscopy. All catalysts were structurally characterized by means of 1H, 13C, and 31P NMR spectroscopy.  相似文献   
105.
资源型城市与老工业基地的转型是现阶段我国社会经济转型的重要内容。由于两者的转型都与不可再生资源的利用有关,所以,转型所面临的问题中有很多相似性,容易引起两者的混淆。本文对资源型城市与老工业基地的概念,转型困境的异同进行了比较,明确了两者的区别,以便在具体的转型工作中准确把握问题的本质,做出正确的决策。  相似文献   
106.
The nutritional value of proteins was investigated after the storage and cooking of rhea M. Gastrocnemius pars interna. Oxidation of basic and aromatic amino acids, surface hydrophobicity and aggregation state of proteins, were determined in raw and cooked meat. In addition, myofibrillar proteins were exposed in vitro to proteases of the digestive tract. Cooking markedly affected the protein surface hydrophobicity. The BBP bound content was three times greater in cooked than in fresh rhea meat. A small increment in tryptophan content after cooking was observed. Storage influenced Schiff bases formation indicating the presence of protein-aldehyde adducts after cooking. High content of Schiff bases was found after cooking of samples stored for 5 days, demonstrating a probable implication of free amino groups, most likely from lysine. Cooking decreased the myofibrillar protein susceptibility to pepsin activity. After cooking, the proteolysis rate by pancreatic enzymes increased. Our findings support the importance of protein aggregation in the nutritional value of meat proteins.  相似文献   
107.
该文研究2-巯基嘧啶(2-MP)对三元阳离子钙钛矿太阳电池光吸收层与空穴传输层的界面进行钝化,钝化改善薄膜及器件的光电性能。瞬态和稳态光致发光荧光光谱表征结果说明钝化后的钙钛矿薄膜非辐射复合被抑制。这均有利于抑制载流子复合和提升开路电压。钝化后薄膜疏水性增强,更好地阻挡水汽侵蚀,提升稳定性。光强依赖性测试结果表明2-MP有效地钝化缺陷。J-V测试表明钝化后器件光电性能明显改善,开路电压最高达1.133 V,效率最高达21.66%。并且优化器件的稳定性显著改善,在氮气中储存97 d后效率保持初始效率的90%。  相似文献   
108.
This paper presents an overview of instrumentation and control (I&C) systems of a pressurized water reactor (PWR) type nuclear power plant (NPP) in Korea. Yonggwang unit 3, which was constructed as a basis model for a Korea standard nuclear power plant (KSNP), is selected as an example for the presentation. This overview is derived from analyzing the I&C systems based on a top-down approach. The I&C systems consist of 30 systems. The 183 I&C cabinets are also analyzed and mapped to the systems. The overview is focused on an interface between the systems and the cabinets. This information will be used to understand the implementation of the I&C systems and to group the systems for an upgrade.  相似文献   
109.
In this paper we introduce a binomial ideal derived from a binary linear code. We present some applications of a Gröbner basis of this ideal with respect to a total degree ordering. In the first application we give a decoding method for the code. In the second one, by associating the code with the set of cycles in a graph, we can solve the problem of finding all codewords of minimal length (minimal cycles in a graph), and show how to find a minimal cycle basis. Finally we discuss some results on the computation of the Gröbner basis.  相似文献   
110.
A method of the synthesis of a new generation of polymers with intrinsic fluorescence—poly(Shiff's bases)–bifluorophores—was developed. These polymers contain two different fluorophores in each unit of the main polymer chain. One of the fluorescent fragments is a donor of electron excitation energy and the second one is an acceptor. The photophysical properties of poly(Shiff's bases)–bifluorophores were investigated. It was shown that in poly(Shiff's bases)–bifluorophores nonradiation energy transfer along the polymer chain in the solid and liquid solutions of polymers takes place. The influence of the disposition of fluorophores in the polymer chain and the distance between them on nonradiation energy transfer were investigated. It was shown that the maximum nonradiation energy transfer is realized in polymers–bifluorophores with a statistical distribution of the fluorophore fragment in the polymer chain. The influence of the distance between a donor and an acceptor of the electron excitation energy on the nonradiation energy transfer was investigated. It was established that nonradiation energy transfer is not observed if the distance between a donor and an acceptor of energy exceeds 10 nm. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 80: 398–406, 2001  相似文献   
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