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101.
SLIM revisited     
SLIM (spectroscopic localization by imaging), a tool for in vivo magnetic resonance spectroscopy that provides compartmental spectra from relatively few phase-encoded data, is limited by the inhomogeneities within each compartment. It is shown that the SLIM-derived spectra approach the average compartmental spectra as the number of phase encoded data approaches infinity, and the convergent rate of the error for each compartment is proportional to the size of the compartment. Numerical simulation studies are conducted to confirm the convergence property. A detailed discussion of the result is provided.  相似文献   
102.
A general, hierarchical method of planning coordinated motions among multiple objects in a dynamic environment is developed. This model consists of a two-phase approach: planning a global path for each object and then locally optimizing along that global path. The applicability of this model to surface-mount manufacturing systems is studied in different scenarios. By changing the priorities of the machines, different results may be obtained. By comparing these results, the best one may then be determined. Simulation results using the two-phase algorithm show an improvement over other planning and control methods  相似文献   
103.
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105.
辛硫磷合成的工艺改进   总被引:1,自引:0,他引:1  
吴祖铃  胡雪薇 《农药》1996,35(5):19-20
本文介绍了辛硫磷的中间体α-氰基苯甲肟钠及其原油合成的工艺改进,总收率达到84%,该方法操作简单,成本低,适合于工业化生产。  相似文献   
106.
The objective of this study was to investigate if coexisting compounds could affect the fate of pharmaceuticals in surface water under solar irradiation. The degradation of metronidazole (MET) in the presence of different coexisting pharmaceuticals was investigated in batch experiments with exposure to sunlight. Tinidazole, which has a similar structure to MET, was employed as an analogue. The results indicated that the presence of an analogue with a similar photosensitive group to MET could inhibit the photodegradation of MET. In addition, the effect of coexisting pharmaceuticals with different absorption spectra on the degradation of MET was investigated. The results showed that the effect depended on the degree of overlapping absorption spectra between MET and the coexisting pharmaceuticals. The relationship between the degree of the influence and the ultraviolet absorption spectra of coexisting pharmaceuticals found in this study could give guidance in assessing the fate of pharmaceuticals in environmental water.  相似文献   
107.
太湖流域水灾害应急对策研究   总被引:1,自引:0,他引:1  
吴浩云  金科 《中国水利》2012,(13):40-43
太湖流域是我国经济社会高度发达的地区之一,发生水灾害时往往会造成重大经济损失。对发生各类水灾害时的应急对策展开研究总结,以减轻水灾害,避免人员伤亡,保障经济社会可持续健康稳定发展,并通过分析典型案例的实际应对过程,为今后开展类似工作提供参考。  相似文献   
108.
In previous adaptive neural network control schemes, neural networks are usually used as feedback compensators. So, only semi-globally uniformly ultimate boundedness of closed-loop systems can be guaranteed, and no methods are given to determine the neural network approximation domain. However, in this paper, it is showed that if neural networks are used as feedforward compensators instead of feedback ones, then we can ensure the globally uniformly ultimate boundedness of closed-loop systems and determine the neural network approximation domain via the bound of known reference signals. It should be pointed out that this domain is very important for designing the neural network structure, for example, it directly determines the choice of the centers of radial basis function neural networks. Simulation examples are given to illustrate the effectiveness of the proposed control approaches.  相似文献   
109.
针对水火电联合运行的电力系统,首次利用优化的方法分析水电和火电间的相互作用规律和负荷的空间分布特性对电力系统节能运行的影响规律,揭示了其联合运行时的水电和火电的运行特征.以此为基础,构建了可充分发挥梯级水电站互动特性的优化调度模型.以一个含有梯级水电站的水火电力系统为例进行分析,结果表明可通过充分发挥水电能源的互补作用,实现非可再生能源的节约和促进能源的可持续高效利用.  相似文献   
110.
To explore the mechanisms of filter mud (FM) in the portland cement clinker formation, and to make effective use of FM in the cement production as lime-based raw materials, the influences of FM on the apparent activation energy of calcium carbonate decomposition, liquid phase amount, crystalline phase and tricalcium silicate polymorphism were investigated by TA, SEM and XRD. The experimental results show that FM can reduce apparent activation energy of calcium carbonate decomposition, and increase liquid phase amount. Appropriate FM replacement ratios are useful to promoting the C3S formation and heightening the C3S content. New phases of α-C2S and C2S·0.5Ca3 (PO4)2 can be found in the clinkers while the ratios are above 15%. In addition, impurities in FM can induce the C3S polymorph to transform.  相似文献   
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