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71.
72.
Jerome BlairAuthor Vitae 《Computer Standards & Interfaces》2011,33(2):122-127
The Peano Kernel Theorem is introduced and a frequency domain derivation is given. It is demonstrated that the application of this theorem yields simple and accurate formulas for estimating the error introduced into a signal by filtering it to reduce noise. The concept of the order of accuracy of a filter is introduced and used as an organizing principle to compare the accuracy of different filters. 相似文献
73.
Sébastien Griffon Amélie Nespoulous Jean-Paul Cheylan Pascal Marty Daniel Auclair 《Virtual Reality》2011,15(4):279-294
Although land managers and policy-makers generally have a good experience of what result can be expected from their decisions,
they are often faced with difficulty when trying to communicate the visual impact of a management option to stakeholders,
particularly when the landscape exhibits a high cultural value. Three-dimensional visualization of the landscape is often
used for communicating with the stakeholders. A challenge in participatory methods for integrated assessment and policy planning
is to view future changes in land use, according to scenarios. A 3-D landscape visualization component, SLE (“Seamless Landscape
Explorer”), has been developed, which is launched after a scenario simulation to allow for exploration of landscape changes.
Pressures causing such changes are translated into changes in the spatial configuration of the landscape. The different types
of land-use are visualized thanks to a library of detailed textures, and vegetation can be added. This has been applied to
a study of four scenarios in the French Mediterranean region, which were set up as part of a participatory process for discussing
the planning of the regional peri-urban and agricultural policy, in an area dominated by the typical culturally sensitive
Mediterranean matorral, (“garrigue” shrubland) surrounding the Pic Saint-Loup mountain. Examples of visualization are shown
and discussed here. 相似文献
74.
Chelnokov A. David S. Kang Wang Marty F. Lourtioz J.-M. 《IEEE journal of selected topics in quantum electronics》2002,8(4):919-927
Deep etching methods applied to semiconductors allow the fabrication of two-dimensional and three-dimensional photonic crystals. The use of chemical, plasma, and focused ion beam etch applied to silicon is reviewed. 相似文献
75.
William T. Riley Steven C. Carson Norman Martin Albert Behar Valerie L. Forman-Hoffman Albert Jerome 《Computers in human behavior》2005,21(6):1005-1018
This study sought to evaluate the feasibility of a researcher configurable self-monitoring program. An initial prototype of the program was developed as a Windows-based drag and drop flow chart interface for the researcher to construct the self-monitoring or diary protocol to be scheduled and displayed to the subject on a Pocket PC. The usability of the desktop researcher interface was evaluated in a small sample of medication trial researchers whose ratings of the prototype were generally positive and provided directions for improvement. The subject interface was then evaluated in an “analog” drug trial of 49 smokers using nicotine gum. These subjects were randomly assigned to either paper-based log or Pocket PC self-monitoring for 3 weeks. Pocket PC subjects were significantly more compliant than the log subjects on recording in the second (65% vs. 39%) and third (69% vs. 39%) weeks of the trial but did not differ from the log condition on total recording entries, likely due to the restrictions on retrospective recording in the Pocket PC program. This study provides support for the feasibility of a researcher configurable electronic diary system which should substantially reduce the programming barriers to electronic self-monitoring and increase the use of real-time monitoring in clinical and research venues. 相似文献
76.
Solid-state intermetallic compound layer growth between copper and 95.5Sn-3.9Ag-0.6Cu solder 总被引:4,自引:0,他引:4
Long-term, solid-state intermetallic compound (IMC) layer growth was examined in 95.5Sn-3.9Ag-0.6Cu (wt.%)/copper (Cu) couples.
Aging temperatures and times ranged from 70°C to 205°C and from 1 day to 400 days, respectively. The IMC layer thicknesses
and compositions were compared to those investigated in 96.5Sn-3.5Ag/Cu, 95.5Sn-0.5Ag-4.0Cu/Cu, and 100Sn/Cu couples. The
nominal Cu3Sn and Cu6Sn5 stoichiometries were observed. The Cu3Sn layer accounted for 0.4–0.6 of the total IMC layer thickness. The 95.5Sn-3.9Ag-0.6Cu/Cu couples exhibited porosity development
at the Cu3Sn/Cu interface and in the Cu3Sn layer as well as localized “plumes” of accelerated Cu3Sn growth into the Cu substrate when aged at 205°C and t>150 days. An excess of 3–5at.%Cu in the near-interface solder field
likely contributed to IMC layer growth. The growth kinetics of the IMC layer in 95.5Sn-3.9Ag-0.6Cu/Cu couples were described
by the equation x=xo+Atnexp [−ΔH/RT]. The time exponents, n, were 0.56±0.06, 0.54±0.07, and 0.58±0.07 for the Cu3Sn layer, the Cu6Sn5, and the total layer, respectively, indicating a diffusion-based mechanism. The apparent-activation energies (ΔH) were Cu3Sn layer: 50±6 kJ/mol; Cu6Sn5 layer: 44±4 kJ/mol; and total layer: 50±4 kJ/mol, which suggested a fast-diffusion path along grain boundaries. The kinetics
of Cu3Sn growth were sensitive to the Pb-free solder composition while those of Cu6Sn5 layer growth were not so. 相似文献
77.
This work demonstrates similarities between epididymal basal cells and macrophages in the mouse. Light microscopic studies of the postnatal development of the murine epididymis showed that basal cells were not present before days 12, 14 and 16 in the cauda, caput and corpus epididymis, respectively. An increase in cell number per unit length of tubule perimeter was demonstrated in all segments between days 20 and 27, when testicular fluid and spermatozoa start entering the epididymis. In the adult, there were more basal cells per unit perimeter in the cauda than caput or corpus epididymis. Conspicuous and consistent expression by basal cells of antigens detected by antibodies against tissue-fixed macrophages (F4/80) and mature macrophages (Mac-1) occurred only after they became established within the epithelium. Basal cells in the cauda epididymis did not display either antigen in the adult, although they persisted in the caput region. Such developmental patterns are compatible with the hypothesis that basal cells play a role in immune defence against sperm autoantigens. 相似文献
78.
David RousseauJean-Daniel Marty Monique MauzacPhilippe Martinoty Astrid BrandtJean-Michel Guenet 《Polymer》2003,44(7):2049-2055
The conformation of side-chain liquid crystal polymers with different mesogen-graft amounts has been studied by small-angle neutron scattering in dilute solutions of toluene-d8 and THF-d8. It is shown that the radius of gyration increases by about twofold when the mesogen-graft amount increases from 0 to 100%, which suggests that the persistence length of the backbone increases by about 4-fold. Comparison with the results reported in the literature on the melt state suggests that the persistence length is not an intrinsic property of side chain liquid crystal polymers, but depends on inter-chain interactions. 相似文献
79.
Golden hamsters (Mesocricetus auratus) and dwarf hamsters (Phodopus campbelli) interacted with a conspecific demonstrator that had recently consumed a flavored food. When given a choice between their demonstrator's flavor and another flavor, the dwarf hamsters preferred the flavor their demonstrator had eaten. Golden hamsters did not prefer their demonstrators' diets when the demonstrators were unrelated adults or littermates, but they did when the demonstrator was their mother. Videotaping the interactions between demonstrators and observers revealed that adult golden hamsters did not investigate foods hoarded by their demonstrators whereas dwarf hamsters did. These results are interpreted in terms of the stimuli that activate feeding behavior systems in these 2 hamster species. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
80.
Tetramethylammonium 3-aminopropyl dimethylsilanolate, readily prepared from bis(3-aminopropyl) tetramethyldisiloxane and tetramethyl-ammonium hydroxide pentahydrate, has been found to serve as a highly effective catalyst for the ring opening polymerization of cyclic siloxanes with an end blocker such as bis(3-aminopropyl) tetramethyldisiloxane to give aminopropyl terminated linear polydimethylsiloxanes. By following a novel two stage procedure, even high molecular weight (5,000–55,000 g/mol) silicone diamines were able to be prepared in a high state of purity; chain extension reactions of these diamines with diisocyanates gave a series of high molecular weight silicone polyureas with good elastomeric properties. 相似文献