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排序方式: 共有1897条查询结果,搜索用时 15 毫秒
41.
Li Ding Timothy Lebo John S. Erickson Dominic DiFranzo Gregory Todd Williams Xian Li James Michaelis Alvaro Graves Jin Guang Zheng Zhenning Shangguan Johanna Flores Deborah L. McGuinness James A. Hendler 《Journal of Web Semantics》2011,9(3):325-333
International open government initiatives are releasing an increasing volume of raw government datasets directly to citizens via the Web. The transparency resulting from these releases not only creates new application opportunities but also imposes new burdens inherent to large-scale distributed data integration, collaborative data manipulation and transparent data consumption. The Tetherless World Constellation (TWC) at Rensselaer Polytechnic Institute (RPI) has developed the Semantic Web-based TWC LOGD portal to support the deployment of linked open government data (LOGD). The portal is both an open source infrastructure supporting linked open government data production and consumption and a vibrant community portal that educates and serves the growing international open government community of developers, data curators and end users. This paper motivates and introduces the TWC LOGD Portal and highlights innovative aspects and lessons learned. 相似文献
42.
A Note on Incorporating Simultaneous Multi‐level Failure Time Data in System Reliability Assessments 下载免费PDF全文
Todd L. Graves Michael S. Hamada 《Quality and Reliability Engineering International》2016,32(3):1127-1135
In this article, we present a method how to evaluate the likelihood for simultaneous failure time data when monitoring is stopped when the system fails. Our method is based on the reliability structure of the system, listing all possible events consistent with the simultaneous data and calculating their contributions to the likelihood. The method is simple to understand and is based on standard probabilistic calculations. We also consider the Jackson and Mosleh 5 method, and some results suggest that the two methods are equivalent. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
43.
Inexact subgraph matching based on type-isomorphism was introduced by Berry et al. [J. Berry, B. Hendrickson, S. Kahan, P. Konecny, Software and algorithms for graph queries on multithreaded architectures, in: Proc. IEEE International Parallel and Distributed Computing Symposium, IEEE, 2007, pp. 1–14] as a generalization of the exact subgraph matching problem. Enumerating small subgraph patterns in very large graphs is a core problem in the analysis of social networks, bioinformatics data sets, and other applications. This paper describes a MapReduce algorithm for subgraph type-isomorphism matching. The MapReduce computing framework is designed for distributed computing on massive data sets, and the new algorithm leverages MapReduce techniques to enable processing of graphs with billions of vertices. The paper also introduces a new class of walk-level constraints for narrowing the set of matches. Constraints meeting criteria defined in the paper are useful for specifying more precise patterns and for improving algorithm performance. Results are provided on a variety of graphs, with size ranging up to billions of vertices and edges, including graphs that follow a power law degree distribution. 相似文献
44.
Sirena Soriano Kristen Curry Qi Wang Elsbeth Chow Todd J. Treangen Sonia Villapol 《International journal of molecular sciences》2022,23(9)
Traumatic brain injury (TBI) causes neuroinflammation and neurodegeneration, both of which increase the risk and accelerate the progression of Alzheimer’s disease (AD). The gut microbiome is an essential modulator of the immune system, impacting the brain. AD has been related with reduced diversity and alterations in the community composition of the gut microbiota. This study aimed to determine whether the gut microbiota from AD mice exacerbates neurological deficits after TBI in control mice. We prepared fecal microbiota transplants from 18 to 24 month old 3×Tg-AD (FMT-AD) and from healthy control (FMT-young) mice. FMTs were administered orally to young control C57BL/6 (wild-type, WT) mice after they underwent controlled cortical impact (CCI) injury, as a model of TBI. Then, we characterized the microbiota composition of the fecal samples by full-length 16S rRNA gene sequencing analysis. We collected the blood, brain, and gut tissues for protein and immunohistochemical analysis. Our results showed that FMT-AD administration stimulates a higher relative abundance of the genus Muribaculum and a decrease in Lactobacillus johnsonii compared to FMT-young in WT mice. Furthermore, WT mice exhibited larger lesion, increased activated microglia/macrophages, and reduced motor recovery after FMT-AD compared to FMT-young one day after TBI. In summary, we observed gut microbiota from AD mice to have a detrimental effect and aggravate the neuroinflammatory response and neurological outcomes after TBI in young WT mice. 相似文献
45.
E.C.D. Todd 《Food Control》2011,22(9):1513-1524
The International Risk Governance Council (IRGC) developed a Risk Governance Framework whose purpose is to help policy makers, regulators and risk managers both understand the concept of risk governance and apply it to their handling of risks. The Framework allows input from the scientific and public health perspective as well as the less-easily measurable side of freedom of choice. For food, the public wants many choices and less regulation, but at the same time safe products to consume. These ideals are at times in conflict. One example of this is the demand for soft cheese made from unpasteurised milk which may be contaminated with L. monocytogenes or other pathogens. Distinguishing between simple, complex, uncertain and ambiguous risks can help to design a risk management strategy. Public health advocates typically see management of soft cheese made from unpasteurised milk as a simple risk (protection of health), whereas for a small but vociferous proportion of the public sees it more of an uncertain or ambiguous one (choice trumps the slight risk of illness). The implications of five management options for the cheese are discussed. The new Codex Guidelines tend to put these cheeses into Option 1, a strict control on the presence of the pathogen, which will be ignored by the cheese aficionados. Other options are worth exploring to give some more choice but at low risk. 相似文献
46.
Voss Horrell Sarah C.; Holohan Dana R.; Didion Lea M.; Vance G. Todd 《Canadian Metallurgical Quarterly》2011,42(3):283
Reports an error in Treating traumatized OEF/OIF veterans: How does trauma treatment affect the clinician by Sarah C. Voss Horrell, Dana R. Holohan, Lea M. Didion and G. Todd Vance (Professional Psychology: Research and Practice, 2011[Feb], Vol 42[1], 79-86). The word “While” was erroneously inserted in the first sentence of the “Clinician Factors” section. The corrected sentence is provided in the erratum. (The following abstract of the original article appeared in record 2011-04544-011.) The authors of this article describe the rewards and challenges for clinicians treating veterans who have served in Operation Enduring Freedom (OEF) and Operation Iraqi Freedom (OIF). Issues of vicarious trauma, secondary traumatic stress, compassion fatigue, and burnout are defined and reviewed, as are compassion satisfaction and posttraumatic growth. Patient, clinician, and organizational characteristics that are likely to affect clinicians working with this clinical population are discussed. Patient factors that may increase strain on clinicians are discussed such as age, likelihood of redeployment, comorbid conditions, attendance issues, and elevated risk for suicide and aggression. Clinician factors, such as theoretical orientation, training, supervision, military affiliation, personal trauma history, spirituality, social support, and self-care, are also discussed as possible risk and protective factors for vicarious trauma and burnout. Organizational influences, such as caseload size and diversity, clinician control and autonomy, use of evidence-based practices, availability of resources, rural isolation, and the philosophy of the clinic, are further discussed. Recommendations for ameliorating risks are discussed relative to each area and include allowing clinicians to plan their own appointments so as to balance their caseload of OEF/OIF veterans, attending to self-care practices, and having a supportive team with thorough training in evidence-based practices. Future empirical research is needed on risk and resiliency factors for clinicians working with traumatized OEF/OIF veterans given that this population is likely to grow. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
47.
Message passing notations (language, package, etc.) typically include some form of asynchronous or synchronous invocation. In a synchronous invocation, the invoker waits for the invocation's servicer to pass back results. Some message passing notations also include early reply or deferred reply (including forwarding), which alters how and when the servicer passes back its results; this additional flexibility is useful in realistic applications. It is well known how to transform a synchronous invocation into only asynchronous invocations. This paper extends such transformations to early reply and forward. This paper also describes the use of these transformations within the implementations of programming notations. Using the transformation simplifies the implementation without significantly affecting run‐time costs. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
48.
The effect of pressure on the measured bimolecular rate constant of the Diels-Alder reaction between maleic anhydride and isoprene was investigated in supercritical CO2 and sub-critical propane. The reaction was carried out at 35°C in CO2 and 80°C in propane. Measured bimolecular rate constants are also compared to predictions from the thermodynamic pressure effect using transilion state theory and the Peng-Robinson equation of state. The rate constants in supercritical C02 agreed closely with the thermodynamic pressure effect predictions over the entire pressure range. Furthermore, the mole fraction based rate constants were found to vary linearly with the density of the solution. The rate constants in the sub-critical propane solvent significantly diverged from the thermodynamic pressure effect predictions and were found to deviate from this linear density dependence at the lower pressures studied. The results are interpreted in the context of local reactant concentrations about the reacting maleic anhydride and solvent-solute and cosolvent-solute interactions. 相似文献
49.
50.
Emma Alexander Qi Guo Sanjeev Koppal Steven J. Gortler Todd Zickler 《International Journal of Computer Vision》2018,126(10):1062-1083
We present the focal flow sensor. It is an unactuated, monocular camera that simultaneously exploits defocus and differential motion to measure a depth map and a 3D scene velocity field. It does this using an optical-flow-like, per-pixel linear constraint that relates image derivatives to depth and velocity. We derive this constraint, prove its invariance to scene texture, and prove that it is exactly satisfied only when the sensor’s blur kernels are Gaussian. We analyze the inherent sensitivity of the focal flow cue, and we build and test a prototype. Experiments produce useful depth and velocity information for a broader set of aperture configurations, including a simple lens with a pillbox aperture. 相似文献