124,720 research outputs found
Current Status of Radio Source Databases
We review the history and present status of radio-source catalogue archiving
and on-line retrieval of radio source data. Large efforts were spent by the
first author in collecting and restoring electronic versions of new and old
source catalogues. Some 67 catalogues with ~520,000 entries were searchable via
the "Einstein On-line Service" (EOLS). When EOLS lost maintenance support in
1994 a group at SAO (Russia) started building software tools to search and
cross-identify objects between the major radio catalogues, maintained as the
"CATalog supporting System" (CATS) at the Special Astrophysical Observatory
(SAO, Russia). The independent efforts in east and west have recently been
joined. Almost 400 different source lists with ~2,000,000 entries have been
archived (and partly prepared) by us. All 5C and Penticton "P"-surveys and many
of the published WSRT survey lists are now available. CATS has been developed
by O. Verkhodanov, S. Trushkin, V. Chernenkov at SAO primarily to support
RATAN-600 radio observations. CATS runs under LINUX and can process requests on
the basis of various net protocols and via email. Almost 70 well-known radio
source catalogues and tables with about 1.3 Mrecords are now available via ftp
from CATS, as well as their documentation files. Twenty of the larger tables
may be searched simultaneously for objects in rectangular boxes of coordinates.
New routines for cross-matching are in progress. More and more catalogues are
being folded into CATS. CATS is supported by RFBR grant 96-07-89075.Comment: 2 pages, no figures; to appear in Proc. "Observational Cosmology with
the New Radio Surveys", eds. M. Bremer, N. Jackson & I. Perez-Fournon, Kluwer
Acad. Pres
Multiround private information retrieval: Capacity and storage overhead
Private information retrieval (PIR) is the problem of retrieving one message out of messages from non-communicating replicated databases, where each database stores all messages, in such a way that each database learns no information about which message is being retrieved. The capacity of PIR is the maximum number of bits of desired information per bit of downloaded information among all PIR schemes. The capacity has recently been characterized for PIR as well as several of its variants. In every case it is assumed that all the queries are generated by the user simultaneously. Here we consider multiround PIR, where the queries in each round are allowed to depend on the answers received in previous rounds. We show that the capacity of multiround PIR is the same as the capacity of single-round PIR. The result is generalized to also include -privacy constraints. Combined with previous results, this shows that there is no capacity advantage from multiround over single-round schemes, non-linear over linear schemes or from -error over zero-error schemes. However, we show through an example that there is an advantage in terms of storage overhead. We provide an example of a multiround, non-linear, -error PIR scheme that requires a strictly smaller storage overhead than the best possible with single-round, linear, zero-error PIR schemes
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The Capacity of Linear Computation Broadcast
The two-user computation broadcast problem is introduced as the setting where user 1 wants message W1 and has side information W0 1 , user 2 wants message W2 and has side information W0 2, and (W1;W0 1 ;W2;W0 2) may have arbitrary dependencies. The goal is to minimize the entropy H(S) of the broadcast information S that simultaneously satisfies both users' demands. It is shown that H(S) H(W1jW0 1) + H(W2jW0 2) min I(W1;W2;W0 2jW0 1 ); I(W2;W1;W0 1jW0 2 ) . Furthermore, for the linear computation broadcast problem, where W1;W0 1;W2;W0 2 are comprised of arbitrary linear combinations of a basis set of independent symbols, the bound is shown to be tight
The capacity of symmetric Private information retrieval
Private information retrieval (PIR) is the problem of retrieving as efficiently as possible, one out of K messages from N non-communicating replicated databases (each holds all K messages) while keeping the identity of the desired message index a secret from each individual database. Symmetric PIR (SPIR) is a generalization of PIR to include the requirement that beyond the desired message, the user learns nothing about the other K - 1 messages. The information theoretic capacity of SPIR (equivalently, the reciprocal of minimum download cost) is the maximum number of bits of desired information that can be privately retrieved per bit of downloaded information. We show that the capacity of SPIR is 1-1/N regardless of the number of messages K, if the databases have access to common randomness (not available to the user) that is independent of the messages, in the amount that is at least 1/(N - 1) bits per desired message bit, and zero otherwise
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Determination of fluphenazine, related phenothiazine drugs and metabolites by combined high-performance liquid chromatography and radioimmunoassay.
Antibodies have been produced in rabbits immunized with a fluphenazine succinate-human serum albumin conjugate. By radioimmunoassay it is possible to quantify fluphenazine (FPZ), related phenothiazine drugs and several of their metabolites at the femtomole level. As little as 370 fmol (160 pg) of FPZ can be detected and up to 0.4 ml of plasma can be added to the incubation mixture (final volume = 1.1 ml). The phenothiazine heterocyclic nucleus is immunodominant and determines the specificity of the antiserum. When a parent drug cross-reacts significantly with antibody, its 7-hydroxide, N-oxide and N-10 side chain altered metabolites can also be determined by the assay. The 8-hydroxide, sulfoxide and 7-hydroxyglucuronide metabolites are not detectable unless present in large amounts. High-performance liquid chromatography was used to separate phenothiazine drugs and metabolites. Since the antiserum has broad specificity, a combined high-performance liquid chromatography and radioimmunoassay procedure permits the identification and quantification of a phenothiazine drug and its serologically reactive metabolites. Patterns of high-performance liquid chromatographic elution and extent of immunologic cross-reaction are characteristic for metabolites relative to the parent drug. This procedure offers distinct advantages in the analysis of this complex family of compounds. FPZ was quantitatively extracted from plasma samples obtained from patients receiving FPZ per os. Although large amounts of serological activity were present in the samples 2 to 6 hr after FPZ ingestion, only 2 to 23% was extractable. The major contributors to the serological activity at times greater than 6 hr were FPZ metabolites. In a preliminary application of the combined techniques, FPZ and a metabolite identified as N-[alpha-(trifluoromethylphenothiazinyl-10)propyl]perazine were quantified in the organic extract of one plasma sample
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Analysis of energy use in crisp frying processes
Copyright @ 2010 Politecnico di Bari - BB PressWith increasing energy costs in industrial food frying processes it is essential to identify inefficiencies and minimise them. A way of achieving this is through the application of energy analysis and modelling techniques to characterise the process and investigate the interactions between the various operating and control parameters. The
overall objective is to reduce energy consumption without compromising product throughput and quality. This paper provides a review of published work on heat and mass transfer in frying processes. Based on this, a simplified analysis of the key processes has been carried out using an energy balance model. The outputs of this model have been validated using data from an industrial crisp frying facility. The knowledge gained from this validation will be used to better understand and appreciate the energy flows in industrial frying processes and should lead to identification of losses and opportunities for energy recovery.The authors would like to acknowledge the financial support from the UK Engineering and Physical Sciences Research Council (EPSRC), Grant NO. EP/G059799/1, for this project as well as the input from the industrial collaborators and academic collaborators from the Universities of Newcastle and Northumbria
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Epitaxial strain and the magnetic properties of canted antiferromagnetic perovskite NaNiF3 thin films
The perovskite crystal structure is known to exhibit a multitude of interesting physical phenomena owing to the intricate coupling of the electronic and magnetic properties to the structure. Fluoroperovskites offer an alternative chemistry to the much more widely studied oxide materials, which may prove advantageous for applications. It is demonstrated here for the first time that the antiferromagnetic perovskite fluoride, NaNiF3, can be synthesized in thin film form. The films were grown via molecular beam epitaxy on SrTiO3 (100) substrates to produce high quality epitaxial films in the thickness range of 5-50 nm. The Pnma structure of the films was confirmed by x-ray diffraction. There was a decrease in the out-of-plane lattice spacing from the bulk value corresponding to a maximum strain of 1.7% in the thinnest film. Canted antiferromagnetism was measured in all films using magnetometry and a negative change in the antiferromagnetic ordering temperature of ΔTN = - 9.1 ± 0.7 K was observed with increasing strain
Aligning identity and strategy: Corporate branding at British Airways in the late 20th century
Published as "Aligning identity and strategy: Corporate branding at British Airways in the late 20th century", California Management Review, 51(3), 6 - 23, 2009. © 2009 by the Regents of the University of California. Copying and permissions notice: Authorization to copy this content beyond fair use (as specified in Sections 107 and 108 of the U. S. Copyright Law) for internal or personal use, or the internal or personal use of specific clients, is granted by the Regents of the University of California for libraries and other users, provided that they are registered with and pay the specified fee via Rightslink® on JSTOR (http://www.jstor.org/r/ucal) or directly with the Copyright Clearance Center, http://www.copyright.com.This article explains the utility of adopting an identity-based view of the corporation, which underpins a diagnostic tool of identity management outlined in this article. Using British Airways as an extensive case history, it examines and analyzes how British Airways' senior executives have intuitively adopted an identity-based perspective as part of the strategic management of the carrier. The analysis is corroborated by insights from the former CEO of British Airways, Lord Marshall, as well as his predecessor, Lord King. The overriding message is that calibrating the multiple identities of the corporation is a critical dimension of strategic management
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Centralised Versus Market-Based Control Under Environment Uncertainty: Case of the Mobile Task Allocation Problem (MTAP)
This paper aims at comparing the centralised versus the market-based approach. This is done in the context of the mobile task allocation problem (MTAP) from the perspective of environmental uncertainty. MTAP is defined as an optimization problem for planning the assignment of service tasks to mobile workers. Environmental uncertainty is introduced through the injection of stochastic tasks and dynamic travel delays. A multi-agent simulator is employed to experiment the behaviour of each approach in reaction to different uncertainty levels. Preliminary results suggest a tentative conceptual model to evaluate the
suitability of each approach to address MTAP in function of uncertainty. It is suggested that uncertainty’s effect on achieved performance is moderated by the timeliness of decision making, workers’ degree of local knowledge, and problem’s complexity and size
Enhancement of singly and multiply strangeness in p-Pb and Pb-Pb collisions at 158A GeV/c
The idea that the reduction of the strange quark suppression in string
fragmentation leads to the enhancement of strange particle yield in
nucleus-nucleus collisions is applied to study the singly and multiply strange
particle production in p-Pb and Pb-Pb collisions at 158A GeV/c. In this
mechanism the strange quark suppression factor is related to the effective
string tension, which increases in turn with the increase of the energy, of the
centrality and of the mass of colliding system. The WA97 observation that the
strange particle enhancement increases with the increasing of centrality and of
strange quark content in multiply strange particles in Pb-Pb collisions with
respect to p-Pb collisions was accounted reasonably.Comment: 8 pages, 3 PostScript figures, in Latex form. submitted to PR
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