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61.
An Investigation of the Relationship Between the Gaussian Process Model Parameters and Surface Area in Three Dimensions
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Rachel T. Silvestrini Anthony C. Silvestrini 《Quality and Reliability Engineering International》2016,32(2):391-402
In this paper, we study the relationship between the fitted parameters in a Gaussian process (kriging) model and the complexity of the resulting response surface. This study is done for models with one response and two input variables. An analytical calculation of surface roughness is used as a measure of the complexity of the response surface fit by the Gaussian process model. Our findings indicate that the size of the fitted model parameters as measured across different fits and data sets do not give indication as to the complexity of the surface. We do, however, show that the magnitude of each of the parameters in a single fitted model gives indication about the amount of variability in the direction of that fitted parameter. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
62.
Tumor Cell Phenotyping: Circulating Tumor Cell Phenotyping via High‐Throughput Acoustic Separation (Small 32/2018)
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63.
Effect of measurement error on epidemiological studies of environmental and occupational exposures 总被引:2,自引:0,他引:2
BG Armstrong 《Canadian Metallurgical Quarterly》1998,55(10):651-656
Random error (misclassification) in exposure measurements usually biases a relative risk, regression coefficient, or other effect measure towards the null value (no association). The most important exception is Berkson type error, which causes little or no bias. Berkson type error arises, in particular, due to use of group average exposure in place of individual values. Random error in exposure measurements, Berkson or otherwise, reduces the power of a study, making it more likely that real associations are not detected. Random error in confounding variables compromises the control of their effect, leaving residual confounding. Random error in a variable that modifies the effect of exposure on health--for example, an indicator of susceptibility--tends to diminish the observed modification of effect, but error in the exposure can create a supurious appearance of modification. Methods are available to correct for bias (but not generally power loss) due to measurement error, if information on the magnitude and type of error is available. These methods can be complicated to use, however, and should be used cautiously as "correction" can magnify confounding if it is present. 相似文献
64.
Rachel Fletcher 《Nexus Network Journal》2011,13(2):487-498
A unique geometric construction known to Thomas Jefferson reveals a rich interplay of root-two geometric elements when applied
to Jefferson’s octagonal plan of Poplar Forest, his eighteenth-century villa retreat. 相似文献
65.
Angela Bonifati Elaine Chang Terence Ho Laks V. S. Lakshmanan Rachel Pottinger Yongik Chung 《The VLDB Journal The International Journal on Very Large Data Bases》2010,19(2):231-256
Peers in a peer-to-peer data management system often have heterogeneous schemas and no mediated global schema. To translate queries across peers, we assume each peer provides correspondences between its schema and a small number of other peer schemas. We focus on query reformulation in the presence of heterogeneous XML schemas, including data–metadata conflicts. We develop an algorithm for inferring precise mapping rules from informal schema correspondences. We define the semantics of query answering in this setting and develop query translation algorithm. Our translation handles an expressive fragment of XQuery and works both along and against the direction of mapping rules. We describe the HePToX heterogeneous P2P XML data management system which incorporates our results. We report the results of extensive experiments on HePToX on both synthetic and real datasets. We demonstrate our system utility and scalability on different P2P distributions. 相似文献
66.
This paper presents a simple model of an AI (artificial intelligence) arms race, where several development teams race to build the first AI. Under the assumption that the first AI will be very powerful and transformative, each team is incentivised to finish first—by skimping on safety precautions if need be. This paper presents the Nash equilibrium of this process, where each team takes the correct amount of safety precautions in the arms race. Having extra development teams and extra enmity between teams can increase the danger of an AI disaster, especially if risk-taking is more important than skill in developing the AI. Surprisingly, information also increases the risks: the more teams know about each others’ capabilities (and about their own), the more the danger increases. Should these results persist in more realistic models and analysis, it points the way to methods of increasing the chance of the safe development of AI. 相似文献
67.
A new semantics in terms of mean field equations is presented for WSCCS (Weighted Synchronous Calculus of Communicating Systems). The semantics captures the average behaviour of the system over time, but without computing the entire state space, therefore avoiding the state space explosion problem. This allows easy investigation of models with large numbers of components. The new semantics is shown to be equivalent to the standard Discrete Time Markov Chain semantics of WSCCS as the number of processes tends to infinity. The method of deriving the semantics is illustrated with examples drawn from biology and from computing. 相似文献
68.
This paper introduces and motivates ADL, a new formal notation for the specification of the temporal and functional behaviour
of concurrent processes. ADL is tailored to be directly compatible with the DORIS design method. It combines a graphical Activity State-Machine (ASM) notation and a model-based Activity Functional Behaviour (AFB) notation. The abstract syntax, and static and dynamic semantics for the ASM notation are given, the dynamic semantics
being given proof-theoretically in many-sorted logic extended with the RTL ‘occurrence’ relation, Θ, and the ERTL ‘holding’ relation, Φ. ADL is used to specify a small network, and proofs are given of its timeliness and safety properties.
Received November 1998 / Accepted in revised form May 2000 相似文献
69.
Rachel Cardell-Oliver 《Formal Aspects of Computing》2000,12(5):350-371
A method is introduced for testing the conformance of implemented real-time systems to timed automata specifications. Uppaal
timed automata are transformed into testable timed transition systems (TTTSs) using a test view. Fault hypotheses and a test
generation algorithm for TTTSs are defined. Results of applying the method are presented.
Received October 1999 / Accepted in revised form November 2000 相似文献
70.
Maria Koutantji Peter McCulloch Shabnam Undre Sanjay Gautama Simon Cunniffe Nick Sevdalis Rachel Davis Piers Thomas Charles Vincent Ara Darzi 《Cognition, Technology & Work》2008,10(4):275-285
We developed a module for surgical team training using briefings in simulated crisis scenarios and here we report preliminary
findings. Nine surgical teams (34 trainees) participated in a pre-training simulation, followed by an interactive workshop
on briefing and checklists, and then a post-training simulation. Both technical and non-technical skills were assessed via
observation during simulations by expert trainers who provided feedback on performances at the end of simulation. Trainees
also reported their attitudes to briefings and evaluated the training. Pre-training attitudes to briefing were positive, some
of which improved post-training and trainees’ evaluation of the training was positive. Surgeons’ technical skill improved
significantly post-training, but their decision-making skill was rated lower than other non-technical skills, compared to
other trainees. The training did not appear to greatly improve non-technical skill performance. Training surgical teams in
simulation is feasible but much more work is needed on measurement development and training strategy to confirm its efficacy
and utility. 相似文献