516 research outputs found
High-Resolution Thermal Wave Imaging of Surface and Subsurface Defects in IC Metal Lines
Using a thermal wave imaging system we have been able to detect and identify a variety of microscopic defects commonly found in fine metal Al connector lines used in the IC industry. The defects of interest are hillocks, surface and subsurface Si and Cu precipitates and subsurface voids and notches. Defects as small as 0.1 μm have been detected. This thermal wave imaging system has also been used to detect subsurface defects in Al and W metal contact plugs
The channels of technology acquisition in commercial firms, and the NASA dissemination program
Technology acquisition in commercial firms, and NASA dissemination progra
THE CHADS2 SCORE PREDICTS ISCHEMIC STROKE IN THE ABSENCE OF ATRIAL FIBRILLATION AMONG PATIENTS WITH CORONARY HEART DISEASE: DATA FROM THE HEART AND SOUL STUDY
Verslag van een excursie van de Kleine Kasgewassen Commissie naar Zuid-Duitsland van 4 tot en met 8 april 1978
Ontwikkeling van een methodiek voor de routing en het screenen van nieuwe potplanten, kuipplanten en eenjarige zomerbloeiers
Ames collaborative study of cosmic ray neutrons
The results of a collaborative study to define both the neutron flux and the spectrum more precisely and to develop a dosimetry package that can be flown quickly to altitude for solar flare events are described. Instrumentation and analysis techniques were used which were developed to measure accelerator-produced radiation. The instruments were flown in the Ames Research Center high altitude aircraft. Neutron instrumentation consisted of Bonner spheres with both active and passive detector elements, threshold detectors of both prompt-counter and activation-element types, a liquid scintillation spectrometer based on pulse-shape discrimination, and a moderated BF3 counter neutron monitor. In addition, charged particles were measured with a Reuter-Stokes ionization chamber system and dose equivalent with another instrument. Preliminary results from the first series of flights at 12.5 km (41,000 ft) are presented, including estimates of total neutron flux intensity and spectral shape and of the variation of intensity with altitude and geomagnetic latitude
Separating and Collapsing Electoral Control Types
[HHM20] discovered, for 7 pairs (C,D) of seemingly distinct standard
electoral control types, that C and D are identical: For each input I and each
election system, I is a Yes instance of both C and D, or of neither.
Surprisingly this had gone undetected, even as the field was score-carding how
many std. control types election systems were resistant to; various "different"
cells on such score cards were, unknowingly, duplicate effort on the same
issue. This naturally raises the worry that other pairs of control types are
also identical, and so work still is being needlessly duplicated.
We determine, for all std. control types, which pairs are, for elections
whose votes are linear orderings of the candidates, always identical. We show
that no identical control pairs exist beyond the known 7. We for 3 central
election systems determine which control pairs are identical ("collapse") with
respect to those systems, and we explore containment/incomparability
relationships between control pairs. For approval voting, which has a different
"type" for its votes, [HHM20]'s 7 collapses still hold. But we find 14
additional collapses that hold for approval voting but not for some election
systems whose votes are linear orderings. We find 1 additional collapse for
veto and none for plurality. We prove that each of the 3 election systems
mentioned have no collapses other than those inherited from [HHM20] or added
here. But we show many new containment relationships that hold between some
separating control pairs, and for each separating pair of std. control types
classify its separation in terms of containment (always, and strict on some
inputs) or incomparability.
Our work, for the general case and these 3 important election systems,
clarifies the landscape of the 44 std. control types, for each pair collapsing
or separating them, and also providing finer-grained information on the
separations.Comment: The arXiv.org metadata abstract is an abridged version; please see
the paper for the full abstrac
Search versus Search for Collapsing Electoral Control Types
Electoral control types are ways of trying to change the outcome of elections
by altering aspects of their composition and structure [BTT92]. We say two
compatible (i.e., having the same input types) control types that are about the
same election system E form a collapsing pair if for every possible input
(which typically consists of a candidate set, a vote set, a focus candidate,
and sometimes other parameters related to the nature of the attempted
alteration), either both or neither of the attempted attacks can be
successfully carried out [HHM20]. For each of the seven general (i.e., holding
for all election systems) electoral control type collapsing pairs found by
Hemaspaandra, Hemaspaandra, and Menton [HHM20] and for each of the additional
electoral control type collapsing pairs of Carleton et al. [CCH+ 22] for veto
and approval (and many other election systems in light of that paper's Theorems
3.6 and 3.9), both members of the collapsing pair have the same complexity
since as sets they are the same set. However, having the same complexity (as
sets) is not enough to guarantee that as search problems they have the same
complexity. In this paper, we explore the relationships between the search
versions of collapsing pairs. For each of the collapsing pairs of Hemaspaandra,
Hemaspaandra, and Menton [HHM20] and Carleton et al. [CCH+ 22], we prove that
the pair's members' search-version complexities are polynomially related (given
access, for cases when the winner problem itself is not in polynomial time, to
an oracle for the winner problem). Beyond that, we give efficient reductions
that from a solution to one compute a solution to the other. For the concrete
systems plurality, veto, and approval, we completely determine which of their
(due to our results) polynomially-related collapsing search-problem pairs are
polynomial-time computable and which are NP-hard.Comment: The metadata's abstract is abridged due to arXiv.org's
abstract-length limit. The paper itself has the unabridged (i.e., full)
abstrac
Onderzoek naar de effecten van variaties in het kasklimaat in combinatie met variaties in het wortelmilieu op de groei, produktie, kwaliteit en het optreden van afwijkingen bij herfsttomaten (1982)
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