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11.
R. Iris Bahar Dan Hammerstrom Justin Harlow William H. Joyner Jr. Clifford Lau Diana Marculescu Alex Orailoglu Massoud Pedram 《Computer》2007,40(1):25-33
Although nanoelectronics won't replace CMOS for some time, research is needed now to develop the architectures, methods, and tools to maximally leverage nanoscale devices and terascale capacity. Addressing the complementary architectural and system issues involved requires greater collaboration at all levels. The effective use of nanotechnology calls for total system solutions 相似文献
12.
13.
Shiqiang Hui Justin RollerSing Yick Xinge ZhangCyrille Decès-Petit Yongsong XieRadenka Maric Dave Ghosh 《Journal of power sources》2007
The advantages of lowering the operation temperature of SOFCs have attracted great interest worldwide. One of the major barriers to decreasing the operation temperature is the ohmic loss of the electrolyte. Maximizing the electrolyte ionic conductivity is of significant importance, especially in the absence of new electrolyte materials. The ionic conductivity of electrolytes can be influenced by many parameters. There has been an enormous effort in the literature for the improvement of the electrolyte ionic conductivity. From a practical point of view, this paper reviews various approaches to enhancing the ionic conductivity of polycrystalline zirconia- and ceria-based oxide electrolytes in the light of composition, microstructure, and processing. Suggestions are given for future work. 相似文献
14.
Comparisons of Urban Travel Forecasts Prepared with the Sequential Procedure and a Combined Model 总被引:4,自引:1,他引:3
Justin D. Siegel Joaquín De Cea José Enrique Fernández Renán E. Rodriguez David Boyce 《Networks and Spatial Economics》2006,6(2):135-148
Detailed analyses and comparisons of urban travel forecasts prepared by applying the state-of-practice sequential procedure
and the solution of a combined network equilibrium model are presented. The sequential procedure for solving the trip distribution,
mode choice and assignment problems with feedback is the current practice in most transportation planning agencies, although
its important limitations are well known. The solution of a combined model, in contrast, results from a single mathematical
formulation, which ensures a well-converged and consistent result. Using a real network, several methods for solving the sequential
procedure with feedback are compared to the solution of the combined model ESTRAUS. The results of these methods are shown
to have various levels of instability. The paper concludes with a call for a new paradigm of travel forecasting practice based
on an internally consistent model formulation that can be solved to a level of precision suitable for comparing alternative
scenarios. 相似文献
15.
Approximate string matching is used for spelling correction and personal name matching. In this paper we show how to use string matching techniques in conjunction with lexicon indexes to find approximate matches in a large lexicon. We test several lexicon indexing techniques, including n-grams and permuted lexicons, and several string matching techniques, including string similarity measures and phonetic coding. We propose methods for combining these techniques, and show experimentally that these combinations yield good retrieval effectiveness while keeping index size and retrieval time low. Our experiments also suggest that, in contrast to previous claims, phonetic codings are markedly inferior to string distance measures, which are demonstrated to be suitable for both spelling correction and personal name matching. 相似文献
16.
Kenta H.T. Cho Mhoyra Fraser Bing Xu Justin M. Dean Alistair J. Gunn Laura Bennet 《International journal of molecular sciences》2021,22(12)
Background: Toll-like receptor (TLR) agonists are key immunomodulatory factors that can markedly ameliorate or exacerbate hypoxic–ischemic brain injury. We recently demonstrated that central infusion of the TLR7 agonist Gardiquimod (GDQ) following asphyxia was highly neuroprotective after 3 days but not 7 days of recovery. We hypothesize that this apparent transient neuroprotection is associated with modulation of seizure-genic processes and hemodynamic control. Methods: Fetuses received sham asphyxia or asphyxia induced by umbilical cord occlusion (20.9 ± 0.5 min) and were monitored continuously for 7 days. GDQ 3.34 mg or vehicle were infused intracerebroventricularly from 1 to 4 h after asphyxia. Results: GDQ infusion was associated with sustained moderate hypertension that resolved after 72 h recovery. Electrophysiologically, GDQ infusion was associated with reduced number and burden of postasphyxial seizures in the first 18 h of recovery (p < 0.05). Subsequently, GDQ was associated with induction of slow rhythmic epileptiform discharges (EDs) from 72 to 96 h of recovery (p < 0.05 vs asphyxia + vehicle). The total burden of EDs was associated with reduced numbers of neurons in the caudate nucleus (r2 = 0.61, p < 0.05) and CA1/2 hippocampal region (r2 = 0.66, p < 0.05). Conclusion: These data demonstrate that TLR7 activation by GDQ modulated blood pressure and suppressed seizures in the early phase of postasphyxial recovery, with subsequent prolonged induction of epileptiform activity. Speculatively, this may reflect delayed loss of early protection or contribute to differential neuronal survival in subcortical regions. 相似文献
17.
Justin R. Barone 《Chemical engineering science》2005,60(10):2579-2584
In this paper, spreading experiments on “heavy” polymer drops are performed. “Heavy” refers to large polymer drops, i.e., the radius of the drop, R, is much larger than the capillary length, κ-1, so that the spreading is dictated by gravity. The zero-shear viscosity can be found from measurements of the time-dependent drop radius or vice versa. Viscosity values found from spreading experiments compare well with the viscosity values found from dynamic rheological experiments. 相似文献
18.
Justin H. Dingle Stephen Zimmerman Alexander L. Frie Justin Min Heejung Jung 《Aerosol science and technology》2019,53(4):449-463
Refractive index and optical properties of biogenic and anthropogenic secondary organic aerosol (SOA) particles were investigated. Aerosol precursors, namely longifolene, α-pinene, 1-methylnaphthalene, phenol, and toluene were oxidized in a Teflon chamber to produce SOA particles under different initial hydrocarbon concentrations and hydroxyl radical sources, reflecting exposures to different levels of nitrogen oxides (NOx). The real and imaginary components (n and k, respectively) of the refractive index at 375?nm and 632?nm were determined by Mie theory calculations through an iterative process, using the χ2 function to evaluate the fitness of the predicted optical parameters with the measured scattering, absorption, and extinction coefficients from a Photoacoustic Extinctiometer and Cavity Attenuated Phase Shift Spectrometer. Single scattering albedo (SSA) and bulk mass absorption coefficient (MAC) at 375?nm were calculated. SSA values of SOA particles from biogenic precursors (longifolene and α-pinene) were ~0.98–0.99 (~6.3% uncertainty), reflecting purely scattering aerosols regardless of the NOx regime. However, SOA particles from aromatic precursors were more absorbing and displayed NOx-dependent SSA values. For 1-methylnaphthalene SOA particles, SSA values of 0.92–0.95 and ~0.75–0.90 (~6.1% uncertainty) were observed under intermediate- and high-NOx conditions, respectively, reflecting the absorbing effects of SOA particles and NOx chemistry for this aromatic system. In mixtures of longifolene and phenol or longifolene and toluene SOA under intermediate- and high-NOx conditions, k values of the aromatic-related component of the SOA mixture were higher than that of 1-methylnaphthalene SOA particles. With the increase in OH exposure, kphenol decreased from 0.10 to 0.02 and 0.22 to 0.05 for intermediate- and high-NOx conditions, respectively. A simple relative radiative forcing calculation for urban environments at λ?=?375?nm suggests the influence of absorbing SOA particles on relative radiative forcing at this wavelength is most significant for aerosol sizes greater than 0.4?µm.
Copyright © 2019 American Association for Aerosol Research 相似文献
19.
Aronson Carl Lawrence Beloskur Douglas Frampton Isaac S. McKie Justin Montbriand Paul 《Polymer Bulletin》2004,52(6):409-419
Summary Functionalization of both linear poly(4-hydroxystyrene) (PHS) and branched poly(4-hydroxystyrene) (PHS-B) was accomplished via a Reimer-Tiemann electrophilic aromatic substitution reaction. Linear and branched poly(4-hydroxystyrene-co-5-vinylsalicylaldehyde) (pHS/5VSA and pHS-B/5VSA) copolymers were observed to undergo acid-catalyzed, novolac type self-crosslinking. Both the pHS/5VSA and pHS-B/5VSA copolymer systems possessed a lower deep ultra violet microlithographic sensitivity compared to linear PHS when formulated in negative photoresists. The sluggishness of the negative photoresists containing 5-vinylsalicylaldehyde functionalized copolymers was attributed to a combination of resonance stabilization and steric hindrance effects. 相似文献
20.
Given a collection of parameterized multi-robot controllers associated with individual behaviors designed for particular
tasks, this paper considers the problem of how to sequence and instantiate the behaviors for the purpose of completing a
more complex, overarching mission. In addition, uncertainties about the environment or even the mission specifications
may require the robots to learn, in a cooperative manner, how best to sequence the behaviors. In this paper, we approach this
problem by using reinforcement learning to approximate the solution to the computationally intractable sequencing problem,
combined with an online gradient descent approach to selecting the individual behavior parameters, while the transitions
among behaviors are triggered automatically when the behaviors have reached a desired performance level relative to a task
performance cost. To illustrate the effectiveness of the proposed method, it is implemented on a team of differential-drive
robots for solving two different missions, namely, convoy protection and object manipulation. 相似文献