375 research outputs found
Impact of electronic alternatives to tobacco cigarettes on indoor air particular matter levels
An aerosol study was carried out in a test room measuring particulate matter (PM) with
an aerodynamic diameter smaller than 10, 4, 2.5 and 1 m (PM10, PM4, PM2.5, PM1) before and
during the use of electronic alternatives to tobacco cigarettes (EATC) IQOS®, GLO®, JUUL®, with
dierent kinds of sticks/pods, as well as during the smoking of a conventional tobacco cigarette.
The aerosol was mainly in the PM1 size range (>95%). All studied EATCs caused lower indoor PM1
concentrations than conventional tobacco cigarettes. Nevertheless, they determined a worsening of
indoor-PM1 concentration that ranged from very mild for JUUL®—depending on the pod used—to
considerably severe for IQOS® and GLO®. Median values ranged from 11.00 (Iqos3 and Juul2) to
337.5 g m3 (Iqos4). The high variability of particle loadings was attributed both to the type of
stick/pod used and to the dierent way of smoking of volunteers who smoked/vaped during the
experiments. Moreover, during vaping IQOS® and GLO® indoor PM1 concentrations reach levels
by far higher than outdoor concentrations that range from 14 to 21 g m3, especially during the
exhalation of the smoke. From these results emerge an urgent need of a legislative regulation limiting
the use of such devices in public places
Space Station Freedom (SSF) Data Management System (DMS) performance model data base
The purpose of this document was originally to be a working document summarizing Space Station Freedom (SSF) Data Management System (DMS) hardware and software design, configuration, performance and estimated loading data from a myriad of source documents such that the parameters provided could be used to build a dynamic performance model of the DMS. The document is published at this time as a close-out of the DMS performance modeling effort resulting from the Clinton Administration mandated Space Station Redesign. The DMS as documented in this report is no longer a part of the redesigned Space Station. The performance modeling effort was a joint undertaking between the National Aeronautics and Space Administration (NASA) Johnson Space Center (JSC) Flight Data Systems Division (FDSD) and the NASA Ames Research Center (ARC) Spacecraft Data Systems Research Branch. The scope of this document is limited to the DMS core network through the Man Tended Configuration (MTC) as it existed prior to the 1993 Clinton Administration mandated Space Station Redesign. Data is provided for the Standard Data Processors (SDP's), Multiplexer/Demultiplexers (MDM's) and Mass Storage Units (MSU's). Planned future releases would have added the additional hardware and software descriptions needed to describe the complete DMS. Performance and loading data through the Permanent Manned Configuration (PMC) was to have been included as it became available. No future releases of this document are presently planned pending completion of the present Space Station Redesign activities and task reassessment
AN-Type Fittings in the International Space System (ISS) Node 2 Ammonia System Technical Assessment Report
Based on an anonymous request, an NESC Assessment Team was formed to investigate potential leakage problems from the ISS Program's Node 2 Anhydrous Ammonia System AN fittings. The Team's charter was to provide the ISS Program with a path to follow, which could include testing, to ensure the ISS Program felt confident that the AN fittings' leakage would not exceed specified limits in orbit. The findings from that assessment are contained in this document
Minimal Conflicting Sets for the Consecutive Ones Property in ancestral genome reconstruction
A binary matrix has the Consecutive Ones Property (C1P) if its columns can be
ordered in such a way that all 1's on each row are consecutive. A Minimal
Conflicting Set is a set of rows that does not have the C1P, but every proper
subset has the C1P. Such submatrices have been considered in comparative
genomics applications, but very little is known about their combinatorial
structure and efficient algorithms to compute them. We first describe an
algorithm that detects rows that belong to Minimal Conflicting Sets. This
algorithm has a polynomial time complexity when the number of 1's in each row
of the considered matrix is bounded by a constant. Next, we show that the
problem of computing all Minimal Conflicting Sets can be reduced to the joint
generation of all minimal true clauses and maximal false clauses for some
monotone boolean function. We use these methods on simulated data related to
ancestral genome reconstruction to show that computing Minimal Conflicting Set
is useful in discriminating between true positive and false positive ancestral
syntenies. We also study a dataset of yeast genomes and address the reliability
of an ancestral genome proposal of the Saccahromycetaceae yeasts.Comment: 20 pages, 3 figure
A formal support to business and architectural design for service-oriented systems
Architectural Design Rewriting (ADR) is an approach for the design of software architectures developed within Sensoria by reconciling graph transformation and process calculi techniques. The key feature that makes ADR a suitable and expressive framework is the algebraic handling of structured graphs, which improves the support for specification, analysis and verification of service-oriented architectures and applications. We show how ADR is used as a formal ground for high-level modelling languages and approaches developed within Sensoria
Instruction sequences for the production of processes
Single-pass instruction sequences under execution are considered to produce
behaviours to be controlled by some execution environment. Threads as
considered in thread algebra model such behaviours: upon each action performed
by a thread, a reply from its execution environment determines how the thread
proceeds. Threads in turn can be looked upon as producing processes as
considered in process algebra. We show that, by apposite choice of basic
instructions, all processes that can only be in a finite number of states can
be produced by single-pass instruction sequences.Comment: 23 pages; acknowledgement corrected, reference update
Advancing automation and robotics technology for the Space Station Freedom and for the U.S. economy
In April 1985, as required by Public Law 98-371, the NASA Advanced Technology Advisory Committee (ATAC) reported to Congress the results of its studies on advanced automation and robotics technology for use on Space Station Freedom. This material was documented in the initial report (NASA Technical Memorandum 87566). A further requirement of the law was that ATAC follow NASA's progress in this area and report to Congress semiannually. This report is the fifteenth in a series of progress updates and covers the period between 27 Feb. - 17 Sep. 1992. The progress made by Levels 1, 2, and 3 of the Space Station Freedom in developing and applying advanced automation and robotics technology is described. Emphasis was placed upon the Space Station Freedom program responses to specific recommendations made in ATAC Progress Report 14. Assessments are presented for these and other areas as they apply to the advancement of automation and robotics technology for Space Station Freedom
A Modular Formalization of Reversibility for Concurrent Models and Languages
Causal-consistent reversibility is the reference notion of reversibility for
concurrency. We introduce a modular framework for defining causal-consistent
reversible extensions of concurrent models and languages. We show how our
framework can be used to define reversible extensions of formalisms as
different as CCS and concurrent X-machines. The generality of the approach
allows for the reuse of theories and techniques in different settings.Comment: In Proceedings ICE 2016, arXiv:1608.0313
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