29,369 research outputs found
On the beneficial role of noise in resistive switching
We study the effect of external noise on resistive switching. Experimental
results on a manganite sample are presented showing that there is an optimal
noise amplitude that maximizes the contrast between high and low resistive
states. By means of numerical simulations, we study the causes underlying the
observed behavior. We find that experimental results can be related to general
characteristics of the equations governing the system dynamics.Comment: 4 pages, 5 figure
What's up prof? Current issues in the visual effects & post-production industry
We interviewed creative professionals at a number of London visual effects and post-production houses. We report on the key issues raised in those interviews: desirable new technologies, infrastructure challenges, personnel and process management
Summary of Discussion Question 4: Energy Expandability of a Linear Collider
We report on Discussion Question 4, in Sub-group 1 (`TeV-class') of the
Snowmass Working Group E3: `Experimental Approaches: Linear Colliders', which
addresses the energy expandability of a linear collider. We first synthesize
discussions of the energy reach of the hardware of the 500 GeV designs for
TESLA and NLC/JLC. Next, we review plans for increasing the energy to 800-1000
GeV. We then look at options for expanding the energies to 1500 GeV and sketch
the two-beam accelerator approach to achieving multi-TeV energies.Comment: Presented at Snowmass 2001 (6 pages, 2 figures
Organizational Climate and Company Productivity: the Role of Employee Affect and Employee Level
Consistent with a growing number of models about affect and behaviour and with arecognition that perception alone provides no impetus for action, it was predicted thatassociations between company climate and productivity would be mediated by average levelof job satisfaction. In a study of 42 manufacturing companies, subsequent productivity wassignificantly correlated in controlled analyses with eight aspects of organizational climate(e.g. skill development and concern for employee welfare) and also with average jobsatisfaction. The mediation hypothesis was supported in hierarchical multiple regressions forseparate aspects of climate. In addition, an overall analysis showed that companyproductivity was more strongly correlated with those aspects of climate that had strongersatisfaction loadings. A second prediction, that managersÂż perceptions of climate would bemore closely linked to company productivity than would those of non-managers, was notsupported. However, managersÂż assessments of most aspects of their companyÂżs climatewere significantly more positive than those of non-managers.Organizational structure, organizational climate, employee welfare, manager,productivity.
New electrical plethysmograph monitors cardiac output
Four-electrode impedance plethysmograph measures ventricular stroke volume of cardiac output of humans. The instrument is automatic, operates with only one recording channel, and minimizes patient discomfort
A study of the ozonolysis of isoprene in a cryogenic buffer gas cell by high resolution microwave spectroscopy
We have developed a method to quantify reaction product ratios using high
resolution microwave spectroscopy in a cryogenic buffer gas cell. We
demonstrate the power of this method with the study of the ozonolysis of
isoprene, CH2=C(CH3)-CH=CH2, the most abundant, non-methane hydrocarbon emitted
into the atmosphere by vegetation. Isoprene is an asymmetric diene, and reacts
with O3 at the 1,2 position to produce methyl vinyl ketone (MVK), formaldehyde,
and a pair of carbonyl oxides: [CH3CO-CH=CH2 + CH2=OO] + [CH2=O +
CH3COO-CH=CH2]. Alternatively, O3 could attack at the 3,4 position to produce
methacrolein (MACR), formaldehyde, and two carbonyl oxides [CH2=C(CH3)-CHO +
CH2=OO] + [CH2=O + CH2=C(CH3)-CHOO]. Purified O3 and isoprene were mixed for
approximately 10 seconds under dilute (1.5-4% in argon) continuous flow
conditions in an alumina tube held at 298 K and 5 Torr. Products exiting the
tube were rapidly slowed and cooled within the buffer gas cell by collisions
with cryogenic (4-7 K) He. High resolution chirped pulse microwave detection
between 12 and 26 GHz was used to achieve highly sensitive (ppb scale),
isomer-specific product quantification. We observed a ratio of MACR to MVK of
2.1 +/- 0.4 under 1:1 ozone to isoprene conditions and 2.1 +/- 0.2 under 2:1
ozone to isoprene conditions, a finding which is consistent with previous
experimental results. Additionally, we discuss relative quantities of formic
acid (HCOOH), an isomer of CH2=OO, and formaldehyde (CH2=O) under varying
experimental conditions, and characterize the spectroscopic parameters of the
singly-substituted 13C trans-isoprene and 13C anti-periplanar-methacrolein
species. This work has the potential to be extended towards a complete
branching ratio analysis, as well towards the ability to isolate, identify, and
quantify new reactive intermediates in the ozonolysis of alkenes
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