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51.
In the cold, Purdue Pegboard (PP) performance declines. The purpose of this study was to determine if this cold-induced impairment is consistent across days (i.e. test-retest reliability) in 5°C. In thermoneutral air (25°C), 14 men were familiarised to the dominant hand (PPa) and bimanual (PPb) PP tasks. They then experienced two 90-min cold exposures (Day 1, Day 2) while wearing ~1 clo. Bare hands were maintained throughout. Performance on both tasks showed high reliability from day to day (intraclass correlations >0.700) in both thermoneutral and cold conditions. However for both tasks, room temperature performance did not predict performance in the cold (intraclass correlations <0.450). When screening applicants for manual labour in the cold, one must consider that room temperature dexterity does not correlate with dexterity in the cold. It is recommended that a 60-min period of cold exposure be employed to assess manual dexterity in these workers. STATEMENT OF RELEVANCE: This study shows that PP performance in room temperature does not predict performance in the cold but performance in the cold is consistent from day to day. When screening applicants for manual labour in the cold, it is recommended that dexterity tests be conducted in the same ambient conditions. 相似文献
52.
Discrete‐time low‐gain control strategies are presented for tracking of constant reference signals for finite‐dimensional, discrete‐time, power‐stable, single‐input, single‐output, linear systems subject to a globally Lipschitz, non‐decreasing input nonlinearity and a locally Lipschitz, non‐decreasing, affinely sector‐bounded output nonlinearity (the conditions on the output nonlinearities may be relaxed if the input nonlinearity is bounded). Both non‐adaptive and adaptive gain sequences are considered. In particular, it is shown that applying error feedback using a discrete‐time ‘integral’ controller ensures asymptotic tracking of constant reference signals, provided that (a) the steady‐state gain of the linear part of the plant is positive, (b) the positive gain sequence is ultimately sufficiently small and (c) the reference value is feasible in a very natural sense. The classes of input and output nonlinearities under consideration contain standard nonlinearities important in control engineering such as saturation and deadzone. The discrete‐time results are applied in the development of sampled‐data low‐gain control strategies for finite‐dimensional, continuous‐ time, exponentially stable, linear systems with input and output nonlinearities. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
53.
54.
Outsourcing continues to capture the attention of researchers as more companies move to outsourcing models as part of their
business practice. Two areas frequently researched and reported in the literature are the reasons why a company decides to
outsource, and outsourcing success factors. This paper describes an in-depth, longitudinal case study that explores both the
reasons why the company decided to outsource and factors that impact on success. The paper describes how Alpha, a very large
Australian communications company, approached outsourcing and how its approach matured over a period of 9 years. The paper
concludes that although a number of reasons are proposed for a company's decision to outsource, lowering costs was the predominant
driver in this case. We also describe other factors identified as important for outsourcing success such as how contracts
are implemented, the type of outsourcing partner arrangement, and outsourcing vendor capabilities.
相似文献
Robert JacobsEmail: |
55.
Herbert Van de Sompel Ryan Chute Patrick Hochstenbach 《International Journal on Digital Libraries》2008,9(2):83-100
The need to federate repositories emerges in two distinctive scenarios. In one scenario, scalability-related problems in the
operation of a repository reach a point beyond which continued service requires parallelization and hence federation of the
repository infrastructure. In the other scenario, multiple distributed repositories manage collections of interest to certain
communities or applications, and federation is an approach to present a unified perspective across these repositories. The
high-level, 3-Tier aDORe federation architecture can be used as a guideline to federate repositories in both cases. This paper
describes the architecture, consisting of core interfaces for federated repositories in Tier-1, two shared infrastructure
components in Tier-2, and a single-point of access to the federation in Tier-3. The paper also illustrates two large-scale
deployments of the aDORe federation architecture: the aDORe Archive repository (over 100,000,000 digital objects) at the Los
Alamos National Laboratory and the Ghent University Image Repository federation (multiple terabytes of image files). 相似文献
56.
Dehen CJ Everly RM Plocinik RM Hedderich HG Simpson GJ 《The Review of scientific instruments》2007,78(1):013106
A new instrument was constructed to perform discrete retardance nonlinear optical ellipsometry (DR-NOE). The focus of the design was to perform second harmonic generation NOE while maximizing sample and application flexibility and minimizing data acquisition time. The discrete retardance configuration results in relatively simple computational algorithms for performing nonlinear optical ellipsometric analysis. NOE analysis of a disperse red 19 monolayer yielded results that were consistent with previously reported values for the same surface system, but with significantly reduced acquisition times. 相似文献
57.
Since verification of computational simulation codes requires significant resources, the ability to measure progress in verification
is critical to assess whether resources are being applied appropriately. Additionally, potential users need to know what fraction
of the software has been order-verified. In this study, the procedures and progress measures presented by Knupp et al. (Measuring
progress order-verification within software development projects. Engineering with Computers, appears in this issue, 2007)
are demonstrated on the Premo software, which simulates compressible aerodynamics through and around general geometries. Premo
was selected for this demonstration because extensive order-verification tests have been previously performed, yet no systematic
effort has been made to assess test-suite completeness or progress. This effort was performed to identify the practical issues
encountered when attempting to apply the ideas by Knupp (Measuring progress order-verification within software development
projects. Engineering with Computers, appears in this issue, 2007) to existing production-quality software. In this work,
a non-specific order-verification exercise is considered, as opposed to an application-specific order-verification exercise,
since past and present Premo order-verification efforts have been motivated by the need to verify all of the code, rather
than portions relevant for specific applications. Constructing an order-verification test suite that verifies the order of
accuracy of all the code capabilities is a major step in measuring progress. A practical approach to test-suite construction
is described that helps create a complete test suite through a combination of coarse-grain code coverage, input-keyword inspection,
discretization-algorithm documentation, and expert knowledge. Some of the difficulties and issues encountered during the construction
of the test suite are described, along with recommendations on how to deal with them. Once the test suite is constructed,
the progress measures proposed by Knupp (Measuring progress order-verification within software development projects. Engineering
with Computers, appears in this issue, 2007) can be evaluated and used to reconstruct the history of progress in Premo verification
over the past several years. Gaps in Premo verification are identified and indicate future directions for making progress.
Additionally, a measure of Premo verification fitness is computed for selected applications commonly simulated in the aerospace
industry. It is hoped that this demonstration will provide a practical example for other software-development groups in measuring
their own verification progress.
Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed-Martin Company, for the United States Department
of Energy’s National Nuclear Security Administration under Contract DE-AC04-94AL85000.
相似文献
Ryan B. Bond (Corresponding author)Email: |
Curtis C. OberEmail: |
Patrick M. KnuppEmail: |
58.
Comparison of bioinformatic data is a common application in the life sciences and beyond. In this communication, a novel Java based software tool, ProteinParser, is outlined. This software tool calculates a detailed consensus, or most common, amino acid at a given position in an aligned protein set, whilst also generating a full consensus protein FASTA output. A second application of this software tool, computing a consensus amino acid given a tolerance threshold, is also demonstrated. The phytase and the common bacterial beta-lactamase proteins are analysed as 'proof of concept' examples. Consensus proteins, as generated by ProteinParser, are regularly utilised in the selection of residues for protein stabilisation mutagenesis; however, this widely applicable software tool will find many alternative applications in areas such as protein homology modelling. 相似文献
59.
Acoustic environments provide many valuable cues for context-aware computing applications. From the acoustic environment we
can infer the types of activity, communication modes and other actors involved in the activity. Environmental or background
noise can be classified with a high degree of accuracy using recordings from microphones commonly found in PDAs and other
consumer devices. We describe an acoustic environment recognition system incorporating an adaptive learning mechanism and
its use in a noise tracker. We show how this information is exploited in a mobile context framework. To illustrate our approach
we describe a context-aware multimodal weather forecasting service, which accepts spoken or written queries and presents forecast
information in several forms, including email, voice and sign languages.
相似文献
Nick RyanEmail: |
60.
Water vapor absorption at 161 wavelengths, from 9.2 to 11.9 micron, of the 12C1602, 13C1602, and 14CI602 lasers was measured using a resonant optoacoustic spectrometer. Results were obtained at several precisely determined vapor concentrations in a flow of pure air at a total pressure of 1 atm. Since the same apparatus and methodology were used for all measurements, a reliable assessment can be made of the relative merits of the three lasers in applications such as atmospheric propagation and ranging. 相似文献