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61.
DM Barch TS Braver LE Nystrom SD Forman DC Noll JD Cohen 《Canadian Metallurgical Quarterly》1997,35(10):1373-1380
A functional magnetic resonance imaging (fMRI) study was conducted to determine whether prefrontal cortex (PFC) increases activity in working memory (WM) tasks as a specific result of the demands placed on WM, or to other processes affected by the greater difficulty of such tasks. Increased activity in dorsolateral PFC (DLPFC) was observed during task conditions that placed demands on active maintenance (long retention interval) relative to control conditions matched for difficulty. Furthermore, the activity was sustained over the entire retention interval and did not increase when task difficulty was manipulated independently of WM requirements. This contrasted with the transient increases in activity observed in the anterior cingulate, and other regions of frontal cortex, in response to increased task difficulty but not WM demands. Thus, this study established a double-dissociation between regions responsive to WM versus task difficulty, indicating a specific involvement of DLPFC and related structures in WM function. 相似文献
62.
63.
H. Blume H.-M. Blüthgen C. Henning P. Osterloh T.G. Noll 《The Journal of VLSI Signal Processing》2002,31(2):117-126
The computational power required in many multimedia applications is well beyond the capabilities of today's multimedia systems. Therefore, the embedding of additional high-performance accelerator multimedia components into these systems is most decisive. This paper presents the embedding of multimedia components into computer systems using reconfigurable coprocessor boards. The goal of those reconfigurable platforms which can be adapted to several applications and which include programmable digital signal processors, control and memory devices as well as dedicated multimedia ASICs is worked out. On the way to such a platform four ASICs for image and text processing are presented. The embedding of these components into a computing system using a CardBus-based coprocessor board is shown. Such a reconfigurable coprocessor board is an important intermediate stage on the way to future hybrid reconfigurable systems on chip. 相似文献
64.
65.
JO Noll 《Canadian Metallurgical Quarterly》1976,133(12):1451-1453
The authors points out that psychotherapists are being increasingly required by law to function as instruments of social control. He believes it is incumbent on therapists to employ full and informed consent procedures with their patients in regard to the effects of providing psychiatric information to potential employers, insurance carriers, and other third parties. 相似文献
66.
Monitoring of toxic compounds in air using a handheld rectilinear ion trap mass spectrometer 总被引:1,自引:0,他引:1
Keil A Hernandez-Soto H Noll RJ Fico M Gao L Ouyang Z Cooks RG 《Analytical chemistry》2008,80(3):734-741
A miniature, handheld mass spectrometer, based on the rectilinear ion trap mass analyzer, has been applied to air monitoring for traces of toxic compounds. The instrument is battery-operated, hand-portable, and rugged. We anticipate its use in public safety, industrial hygiene, and environmental monitoring. Gaseous samples of nine toxic industrial compounds, phosgene, ethylene oxide, sulfur dioxide, acrylonitrile, cyanogen chloride, hydrogen cyanide, acrolein, formaldehyde, and ethyl parathion, were tested. A sorption trap inlet was constructed to serve as the interface between atmosphere and the vacuum chamber of the mass spectrometer. After selective collection of analytes on the sorbent bed, the sorbent tube was evacuated and then heated to desorb analyte into the instrument. Sampling, detection, identification, and quantitation of all compounds were readily achieved in times of less than 2 min, with detection limits ranging from 800 parts per trillion to 3 parts per million depending on the analyte. For all but one analyte, detection limits were well below (3.5-130 times below) permissible exposure limits. A linear dynamic range of 1-2 orders of magnitude was obtained over the concentration ranges studied (sub-ppbv to ppmv) for all analytes. 相似文献
67.
Noll JD Bugarski AD Patts LD Mischler SE McWilliams L 《Environmental science & technology》2007,41(3):710-716
Elemental carbon (EC) is currently used as a surrogate for diesel particulate matter (DPM) in underground mines since it can be accurately measured at low concentrations and diesels are the only source of submicrometer EC in underground mines. A disadvantage of using EC as a surrogate for DPM is that the fraction of EC in DPM is a function of various engine parameters and fuel formulations, etc. In order to evaluate how EC predicts DPM in the underground mining atmosphere, measurements of total carbon (TC; representing over 80% of the DPM) and EC were taken away from potential interferences in four underground metal/non-metal mines during actual production. In a controlled atmosphere, DPM mass, TC, and EC measurements were also collected while several different types of vehicles simulated production with and without different types of control technologies. When diesel particulate filters (DPFs) were not used, both studies showed that EC could be used to predict DPM mass or TC. The variability of the data started to increase at TC concentrations below 230 microg/m3 and was high (> +/- 20%) at TC concentrations below 160 microg/m3, probably due to the problem with sampling organic carbon (OC) at these concentrations. It was also discovered that when certain DPFs were used, the relationship between DPM and EC changed at lower DPM concentrations. 相似文献
68.
The focus of this paper is the experimental determination of size-resolved estimates of both deposition and suspension velocities for large, airborne particles (greater than 10 μm diameter). Measurements of particle dry flux onto the top and bottom surface of a smooth, horizontal, surrogate surface were divided by measurements of the concentration of airborne particles to provide estimates of deposition and suspension velocities in 14 size intervals between 5 and 100 μm diameter. Eddy inertial deposition efficiencies (ηdi) were determined as a function of eddy Stokes numbers (Stke) larger than 1 and the results agree with the model of Slinn and Slinn (1980). The model was used to provide estimates of both the inertial and gravitational components for total upward and downward particle velocities. Experimental results for individual particle size intervals produced highly variable results. Much of this variation can be attributed to experimental errors associated with the nature of the atmospheric experiments and not to problems with the model. Upward large particle suspension velocities are similar in magnitude to downward deposition velocities at higher wind speeds and represent a counteracting process to deposition processes that cannot be ignored for accurate representation of the long-range transport for particles between 5 and 50 μm diameter. 相似文献
69.
Andrea Preuβ Elaheh Pousaneh Julian Noll Tobias Rüffer Alexaner Jakob Lutz Mertens Michael Mehring Heinrich Lang 《中国稀土学报(英文版)》2018,36(5):537-543
The lanthanum(Ⅲ) complex [Li(thf)_3(μ-CI)La{N(SiMe_3)_2}_3](3) was obtained by the reaction of LaCl_3 with three equiv of Li[N(SiMe_3)_2]_3 in a tetrahydrofuran solution. The molecular structure of 3 in the solid state was characterized by a tetracoordinated anionic lanthanide(Ⅲ) amide in form of an adduct with LiCl(thf)_3 as evidenced by single crystal X-ray structure analysis. In order to study the suitability of 3 as a precursor for the deposition of La_2O_3/LiLaSiO4 by thin layer deposition techniques,its thermal behavior was investigated by thermogravimetry(TG) and TG-MS-coupled studies. TG studies show a two-step decomposition process, whereby volatile decomposition products can be detected during the second decomposition step. TG measurements under an atmosphere of oxygen produced La_2O_3, Calcination processes of 3 under ambient atmosphere for 10 h at 1000 ℃ gave La_2O_3 and LiLaSiO_4,which was confirmed by PXRD studies. Metal-organic 3 was applied as spin-coating precursor for La_2O_3 thin film formation giving the as-deposited layers nearly crack-free. 相似文献
70.
The objective of an on-going DFG research project is to investigate the effect of non-linear stress–strain curves (e.g. τ12–γ12) on the fatigue life simulation of carbon fiber reinforced polymer (CFRP) laminates under variable amplitude cyclic loading. Based on the critical element concept of Reifsnider and Stinchcomb appropriate models including a secant modulus iteration for the non-linear stress analysis, the evaluation of inter-fiber fracture effects applying a fracture plane criterion, and appropriate continuum mechanics based stiffness degradation algorithms to treat both inter-fiber cracking and ply delamination were implemented into an existing fatigue life prediction software. Using this software the fatigue life of a quasi-isotropic vinylester/urethane/carbon fiber composite laminate subjected to miniTWIST variable amplitude loading was analyzed and compared to experimental data. 相似文献