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排序方式: 共有252条查询结果,搜索用时 15 毫秒
91.
Bufler F.M. Graf P. Meinerzhagen B. Adeline B. Rieger M.M. Kibbel H. Fischer G. 《Electron Device Letters, IEEE》1997,18(6):264-266
Ohmic minority and majority drift mobilities as well as saturation velocities are reported for unstrained and strained Si1-xGe x alloys up to z=0.31. The electron-transport model is verified by measurements of the in-plane majority drift mobility in strained Si1-xGex samples for various dopant and Ge concentrations. Saturation velocities are determined by full-band Monte Carlo simulations. There is no substantial decrease in the mobility perpendicular to the Si/SiGe interface for doping concentrations above 1019 cm-3 and growing x. In contrast, the saturation-drift velocity is strongly reduced with x 相似文献
92.
Learning Concepts from Sensor Data of a Mobile Robot 总被引:1,自引:0,他引:1
Machine learning can be a most valuable tool for improving the flexibility and efficiency of robot applications. Many approaches to applying machine learning to robotics are known. Some approaches enhance the robot's high-level processing, the planning capabilities. Other approaches enhance the low-level processing, the control of basic actions. In contrast, the approach presented in this paper uses machine learning for enhancing the link between the low-level representations of sensing and action and the high-level representation of planning. The aim is to facilitate the communication between the robot and the human user. A hierarchy of concepts is learned from route records of a mobile robot. Perception and action are combined at every level, i.e., the concepts are perceptually anchored. The relational learning algorithm GRDT has been developed which completely searches in a hypothesis space, that is restricted by rule schemata, which the user defines in terms of grammars. 相似文献
93.
Optimisation of nitrifying activated sludge plants towards nutrient removal (denitrification and enhanced P-removal) leads to a substantial reduction of operating costs and improves effluent and operating conditions. At WWTP Zürich-Werdh?elzli, initially designed for nitrification only, an anoxic zone of 28% of total activated sludge volume was installed and allowed 60% nitrogen elimination besides several other optimisations. In 2001 the operation of WWTP Zürich-Glatt was stopped and the wastewater was connected to WWTP Werdh?elzli. To improve nitrogen removal, WWTP Werdh?elzli co-financed two research projects; one for separate digester supernatant treatment with the anammox process operating two SBRs in series and the other applying NH4 sensors for aeration control in order to decrease energy consumption and raise effluent quality. The results of both projects and the consequences for WWTP Werdh?elzli are discussed in this paper. 相似文献
94.
GP Jones A Birkett A Sanigorski AJ Sinclair PT Hooper T Watson V Rieger 《Canadian Metallurgical Quarterly》1994,32(6):521-525
The authors examined the role of perceived family support and symptoms of depression as predictors of survival in a sample of 78 in-center hemodialysis patients. Cox regression analysis revealed significant effects for family support (p < .005), blood urea nitrogen (p < .01), and age (p < .005). The effect for depression was not significant. The Cox model indicated that a 1-point increase on the family support measure was associated with a 13% reduction in the hazard rate (i.e., mortality). Estimated 5-year mortality rates among low family support patients were approximately 3 times higher than estimated mortality for high support patients. Differences in patient adherence to the dietary and medication regimens failed to explain the significant effect of family support. 相似文献
95.
The assumption that letters automatically activate corresponding keypresses in skilled typing was investigated. Participants responded to the color of letters (congruent condition: responding finger was the one usually used to type the letter). Participants skilled in typing showed a congruency effect: unskilled participants did not (Experiment 1). The automatic activation included characteristics of the movement usually performed to type the letters (Experiment 2). Responding with crossed hands on an external response device (Experiment 3) provided evidence for effector-dependent representations only, whereas responding on a keyhoard (Experiment 4) resulted in evidence for effector-dependent and spatial representations. Thus, motoric skill proficiency is accompanied by automatic activation processes that probably contribute to high performance levels. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
96.
Cremer C. Schier M. Baumeister G. Ebhinghaus G. Huber H. Kunkel W. Bauer J.G. Kristen G. Rieger J. Schimpe R. Strzoda R. 《Electronics letters》1994,30(19):1625-1626
A semiconductor optical amplifier, a grating demultiplexer and a photodiode array were integrated in InGaAsP/InP to form a WDM receiver chip. 10 wavelength channels (TE or TM polarisation) in the 1.54 μm wavelength region with a channel spacing of 2 nm were detected with a crosstalk of less than -20 dB and a responsivity of up to 8 A/W 相似文献
97.
98.
Rudimentary cilia have been observed in muscle cells lining the tube feet of Ophioderma brevispinum (Ophiuroidea) and in muscle cells of the body wall and parapodial glands of Owena fusiformis (Polychaeta). A diplosomal basal body is associated with each cilium. Striated rootlets are absent. This is the first report on rudimentary cilia in muscle cells of an echinoderm and an annelid. 相似文献
99.
Glowatzki H Bröker B Blum RP Hofmann OT Vollmer A Rieger R Müllen K Zojer E Rabe JP Koch N 《Nano letters》2008,8(11):3825-3829
C60 adsorbed on a monolayer of hexaazatriphenylene-hexanitrile (HATCN) on Ag(111) is investigated by ultraviolet photoelectron spectroscopy (UPS) and scanning tunneling microscopy. UPS and quantum-mechanical modeling show that HATCN chemisorbed on Ag(111) displays metallic character. This metallic molecular layer decouples C60 electronically from the Ag substrate and simultaneously acts both as template for the stable adsorption of isolated C60 molecules at room temperature and as "soft" metallic contact for subsequently deposited molecules. 相似文献
100.
One‐Step Synthesis of Photoluminescent Covalent Polymeric Nanocomposites from 2D Silicon Nanosheets 下载免费PDF全文
Tobias Helbich Alina Lyuleeva Theresa Ludwig Lavinia M. Scherf Thomas F. Fässler Paolo Lugli Bernhard Rieger 《Advanced functional materials》2016,26(37):6711-6718
Herein, the synthesis and characterization of the first polymeric nanocomposite based on silicon nanosheets (SiNSs) are reported. In a one‐step reaction, the formation of the polymeric matrix material and simultaneous functionalization of the SiNSs with polymers occur via radical polymerization of organic monomers such as styrene, methyl methacrylate, and acrylic acid. Depending on the purification method used, a covalently linked nanocomposite or the functionalized SiNSs are obtained. SiNSs decompose when exposed to basic conditions or to UV light. The UV‐light‐based decomposition is briefly investigated. In the nanocomposite, the stability of the 2D nanomaterial enhances significantly against these external influences, while the optoelectronic properties (e.g., photoluminescence) of the SiNSs and the processing characteristics of the polymeric matrix are preserved. 相似文献