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991.
The resources of various settings located in one geographic area of a state were linked in an attempt to resolve educational problems. Using the concept of collegium as the mechanism for working together, the assumptions governing these efforts are presented, rationale for successes and failures are discussed, and suggestions are made on how such undertakings may relate to the field of school psychology. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
992.
993.
The design of specialized processing array architectures, capable of executing any given arbitrary algorithm, is proposed. An approach is adopted in which the algorithm is first represented in the form of a dataflow graph and then mapped onto the specialized processor array. The processors in this array execute the operations included in the corresponding nodes (or subsets of nodes) of the dataflow graph, while regular interconnections of these elements serve as edges of the graph. To speed up the execution, the proposed array allows the generation of computation fronts and their cancellation at a later time, depending on the arriving data operands; thus it is called a data-driven array. The structure of the basic cell and its programming are examined. Some design details are presented for two selected blocks, the instruction memory and the flag array. A scheme for mapping a dataflow graph (program) onto a hexagonally connected array is described and analyzed. Two distinct performance measures-mapping efficiency and array utilization-and some performance results are discussed 相似文献
994.
Hamycin incorporated into liposomes containing phosphatidylcholine (SPC) and phosphatidic acid (PA) had reduced toxicity and an enhanced antifungal activity in experimental aspergillosis in balb/c mice. Incorporation of cholesterol into liposomes led to a dose dependent decrease in the toxicity of hamycin. The LD50 (mg/kg) of hamycin contained in SPC/cholesterol/PA (molar ratio 4:5:1) liposomes was 2.8 whereas that in SPC/PA liposomes (molar ratio 9:1) was 0.35. Although the free drug had little or no protective effect on the animals, those administered liposomal hamycin at an equivalent dose (0.1 mg/kg) in the absence of cholesterol (SPC/PA; molar ratio 9:1) showed 90% survival after seven days of therapy. On the other hand the presence of cholesterol in the carrier phosphatidic acid liposomes (SPC/cholesterol/PA; molar ratio 4:5:1) at a similar dose (0.1 mg/kg) led to a 60% survival over the same time period. Hamycin incorporation in phosphatidic acid liposomes both in the presence or absence of cholesterol was found to be effective in reducing the fungal load in lung, liver, spleen and kidney. Studies with distribution of hamycin in various tissues by HPLC showed a significant reduction in the concentration of the liposomal drug in circulation as compared to those seem after administration of free drug. 相似文献
995.
A complex immuno-chemical treatment (immuno-stimulation, blockage of virus replication, interferon induction) was applied to 23 patients with warts and vegetations with various localisations. Results confirmed the treatment efficiency. 相似文献
996.
A new gauge configuration for the measurement of outside dimensions up to 70 mm is described. The main advantage of the instrument is that it can be used to perform absolute measurements, i.e., without adjustment operations. The instrument has potential applications in many industries engaged in the manufacture of parts in relatively small lots.Translated from Izmeritel'naya Tekhnika, No. 10, pp. 32–33, October, 1993. 相似文献
997.
998.
It was shown that one can improve transmission performance in ultra-long-haul wavelength-division-multiplexed (WDM) systems by matching the input pulsewidth to the path-averaged dispersion (PAD) in the line. Wider pulses should be used for higher values of PAD, and vice versa. It was also noted that this pulsewidth selection is only effective in the dispersion-managed soliton (DMS) propagation regime but not in the chirped return-to-zero (CRZ) regime. 相似文献
999.
1000.
Gashinova M.S. Goubina M.N. Guoyong Zhang Kolmakov I.A. Kolmakov Y.A. Vendik I.B. 《Microwave Theory and Techniques》2003,51(3):792-795
This paper presents design and measurement results of a high-T/sub c/ superconducting planar filter based on a pair of coupled modified hairpin resonators considered to be a key constituent of the filter structure. This provides the filter characteristics, which are very close to the Chebyshev prototype of the same order. 相似文献