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91.
A wideband wattmeter for measuring active power over a frequency range of dc to 500 kHz is described. The wattmeter is based on the three-voltmeter method in which three rms voltage measurements are used to calculate power. The wattmeter active power uncertainty is estimated to be within 0.03% from dc to 20 kHz and within 1.5% to 500 kHz 相似文献
92.
93.
Recent studies have identified molecules that interact with integrins and appear to participate in the signaling pathways that regulate integrin adhesiveness. Clues provided by studies of these molecules point to the integration by integrins of signal transduction pathways implicated in cell division and activation. 相似文献
94.
The cytosolic chaperonin containing TCP-1 (CCT) is known to keep fold cytoskeletal proteins and is involved in the proper organization of the cytoskeleton. These studies are based on the assumption that growth responses linked to structural rearrangement of the plant cytoskeleton include the action of CCT and the need for newly synthesized tubulin. The presence of the alpha- and epsilon-subunits of CCT was investigated in soluble fractions of protein extracts from maize mesocotyls and coleoptiles at distinct growth stages. The CCT-subunits, tubulins and actin decreased in the coleoptile in response to far-red light. In addition, independent from light treatment, the amount of CCT epsilon abundance declined with age in coleoptiles and mesocotyls between 2 and 4.5 days after sowing. In contrast to CCT epsilon, no significant light regulation of CCT alpha was found in the mesocotyl. In two day old, light-grown rapidly elongating coleoptiles part of the CCT alpha subunit and the bulk of actin and tubulin was found shifted into fractions of high molecular weight complexes when compared to slowly elongating, dark grown coleoptiles. In 4.5 day old, etiolated and elongating coleoptiles, part of both CCT-subunits and cytoskeleton proteins were found in fractions of high molecular weight. A complete disappearance of these polypeptides was observed in old far-red irradiated growth-arrested coleoptiles. CCT epsilon was found to be colocalized to microtubular structures and to the nucleus. We conclude from our data that abundance of CCT-subunits in soluble extracts is dependent on age and light treatment, but independent from the growth stage of mesocotyl and coleoptile. 相似文献
95.
MineSet aids knowledge discovery and supports decision making based on relational data. It uses visualization and data mining to arrive at interesting results. Providing diverse visualization tools lets users choose the most appropriate method for a given problem. The client-server architecture performs most of the computationally intensive tasks on a server, while the processed results return to the client for visualization. The paper discusses MineSet database visualization and data mining visualization 相似文献
96.
97.
98.
Candelier P. Mondon F. Guillaumot B. Reimbold G. Martin F. 《Electron Device Letters, IEEE》1997,18(7):306-308
A simplified flash EEPROM process was developed using high-temperature LPCVD oxide both as flash cells interpoly dielectrics and as peripheral transistors gate oxide (decoding logic). An O2 anneal at 850°C lowers charge trapping and interface trap density induced by Fowler-Nordheim injection. However, electron trapping remains slightly higher than with dry thermal oxide. Similar memory charge loss and write-erase endurance are obtained as for ONO-insulated cells. HTO thus proves to have the required quality and reliability to be used in flash EEPROMs 相似文献
99.
Salama H.F. Reeves D.S. Viniotis Y. 《Selected Areas in Communications, IEEE Journal on》1997,15(3):332-345
Multicast (MC) routing algorithms capable of satisfying the quality of service (QoS) requirements of real-time applications will be essential for future high-speed networks. We compare the performance of all of the important MC routing algorithms when applied to networks with asymmetric link loads. Each algorithm is judged based on the quality of the MC trees it generates and its efficiency in managing the network resources. Simulation results over random networks show that unconstrained algorithms are not capable of fulfilling the QoS requirements of real-time applications in wide-area networks. Simulations also reveal that one of the unconstrained algorithms, reverse path multicasting (RPM), is quite inefficient when applied to asymmetric networks. We study how combining routing with resource reservation and admission control improves the RPM's efficiency in managing the network resources. The performance of one semiconstrained heuristic, MSC, three constrained Steiner tree (CST) heuristics, Kompella, Pasquale, and Polyzos (1992), constrained adaptive ordering (CAO), and bounded shortest multicast algorithm (BSMA), and one constrained shortest path tree (CSPT) heuristic, the constrained Dijkstra heuristic (CDKS) are also studied. Simulations show that the semiconstrained and constrained heuristics are capable of successfully constructing MC trees which satisfy the QoS requirements of real-time traffic. However, the cost performance of the heuristics varies. The BSMA's MC trees are lower in cost than all other constrained heuristics. Finally, we compare the execution times of all algorithms, unconstrained, semiconstrained, and constrained 相似文献
100.
A value-based test is presented for economic screening of electric utility demand-side management (DSM) programs. The widely used least cost test is valid if the programs do not alter the amount or value of energy services provided to customers. But, in general, DSM programs have such effects and, as a result, the value consumers receive is changed. A more general economic efficiency test, the most value test, provides a practical method for considering the effects of DSM on customer value. The version presented allows for multiple load periods and can account for rate impacts on several customer classes. Four typical DSM programs are evaluated as illustrations 相似文献