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Cooperative Sensor Anomaly Detection using Global Information

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Tsinghua Science and Technology 2013年第3期18卷 209-219页

作者： Rui Zhang Ping Ji Dinkar Mylaraswamy Mani Srivastava Sadaf Zahedi Intel-GE CareInnovations CAUS the Computer Science Department City University of New YorkNYUS Honeywell Aerospace Advanced Technology MNUS University of California Los AngelesCAUS

Sensor networks are deployed in many application areas nowadays ranging from environment monitoring, industrial monitoring, and agriculture monitoring to military battlefield sensing. The accuracy of sensor readings is without a doubt one of the most important measures to evaluate the quality of a sensor and its network. Therefore, this work is motivated to propose approaches that can detect and repair erroneous （i.e., dirty） data caused by inevitable system problems involving various hardware and software components of sensor networks. As information about a single event of interest in a sensor network is usually reflected in multiple measurement points, the inconsistency among multiple sensor measurements serves as an indicator for data quality problem. The focus of this paper is thus to study methods that can effectively detect and identify erroneous data among inconsistent observations based on the inherent structure of various sensor measurement series from a group of sensors. Particularly, we present three models to characterize the inherent data structures among sensor measurement traces and then apply these models individually to guide the error detection of a sensor network. First, we propose a multivariate Gaussian model which explores the correlated data changes of a group of sensors. Second, we present a Principal Component Analysis （PCA） model which captures the sparse geometric relationship among sensors in a network. The PCA model is motivated by the fact that not all sensor networks have clustered sensor deployment and clear data correlation structure. Further, if the sensor data show non-linear characteristic, a traditional PCA model can not capture the data attributes properly. Therefore, we propose a third model which utilizes kernel functions to map the original data into a high dimensional feature space and then apply PCA model on the mapped linearized data. All these three models serve the purpose of capturing the underlying phenomenon of a sen

关键词： wireless sensor network faulty detection kernel Principal Component Analysis (PCA)

Forms and Aesthetics of Bridges

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Engineering 2018年第2期4卷 103-112页

作者： Man-Chung Tang Chinese Academy of Engineering Beijing 100088 China us National Academy of Engineering Washington DC 20001 USA T.Y. Lin International group San Francisco CA 94104 USA

The objective of a bridge design is to produce a safe bridge that is elegant and satisfies all functionality requirements, at a cost that is acceptable to the owner. A successful bridge design must be natural, simple, original, and harmonious with its surroundings. Aesthetics is not an additional consideration in the design of a bridge, but is rather an integral part of bridge design. Both the structural configuration and the aesthetics of a bridge must be considered together during the conceptual design stage. To achieve such a task, the bridge design engineer must have a good understanding of structural theory and bridge aesthetics.

关键词： Form Aesthetics Bridge Concept Design Environment

2％硝化甘油眼膏用于儿童近视眼的安全性和有效性：一年多中心双盲安慰剂对照平行研究

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美国医学会眼科杂志（中文版） 2005年第3期17卷 136-136页

作者： R. Michael Siatkowski Susan Cotter Joseph M. Miller Colin A. Scher R. Stephens Crockett Gary D. Novack 雷嘉启（译） us pirenzepine study group 不详

目的：为了评估相对选择性M1拮抗剂盐硝化甘油在延缓学龄儿童近视眼进程方面的安全性和有效性。

关键词：硝化甘油学龄儿童安全性近视眼安慰剂对照中心双盲平行眼膏相对选择性

Uptake and transformation of arsenic during the reproductive life stage of Agaricus bisporus and Agaricus campestris

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Journal of Environmental Sciences 2016年第11期28卷 140-149页

作者： Michelle M.Nearing Iris Koch Kenneth J.Reimer Environmental Sciences group Royal Military College of Canada

Fruiting bodies from the Agaricus genus have been found to contain non-toxic arsenobetaine（AB） as a major compound. It is unknown whether AB is formed during the vegetative or reproductive life stages of the fungus, or by the surrounding microbial community, but AB＇s structural similarity to glycine betaine has led to the hypothesis that AB may be adventitiously accumulated as an osmolyte. To investigate the potential formation of AB during the reproductive life stage of Agaricus species, growth substrate and fungi were collected during the commercial growth of Agaricus bisporus and analyzed for arsenic speciation using HPLC-ICP-MS. AB was found to be the major arsenic compound in the fungus at the earliest growth stage of fruiting（the primordium）. The growth substrate mainly contained arsenate（As（V））. The distribution of arsenic in an A. bisporus primordium grown on As（V） treated substrate, and in a mature Agaricus campestris fruiting body collected from arsenic contaminated mine tailings, was mapped using two dimensional XAS imaging. The primordium and stalk of the mature fruiting body were both found to be growing around pockets of substrate material containing higher As concentrations, and AB was found exclusively in the fungal tissues. In the mature A. campestris the highest proportion of AB was found in the cap, supporting the AB as an osmolyte hypothesis. The results have allowed us to pinpoint the fungus life stage at which AB formation takes place,namely reproduction, which provides a direction for further research.

关键词： Arsenobetaine Arsenic Agaricus Fungi HPLC-ICP-MS XAS imaging

Incidence and risk of herpes zoster in patients with ulcerative colitis and Crohn’s disease in the usA

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Gastroenterology Report 2023年第1期11卷 271-281页

作者： David Singer Philippe Thompson-Leduc Deepshekhar Gupta Wendy Y.Cheng Sara Poston Siyu Ma John E.Pawlowski Mei Sheng Duh Eric D.Morris Francesca Devine Francis A.Farraye us Health Outcomes and Epidemiology—Vaccines GSKPhiladelphiaPAUSA Health Economics and Outcomes Research Analysis GroupInc.MontrealQuebecCanada Health Economics and Outcomes Research Analysis GroupInc.Menlo ParkCAUSA Health Economics and Outcomes Research Analysis GroupInc.BostonMAUSA Tufts Medical Center BostonMAUSA Medical Affairs GSKPhiladelphiaPAUSA Health Economics and Outcomes Research Analysis GroupInc.New YorkNYUSA Division of Gastroenterology and Hepatology Mayo ClinicJacksonvilleFLUSA

Background:Patients with inflammatory bowel disease(IBD)are at increased risk of herpes zoster(HZ).We evaluated the incidence of HZ in ulcerative colitis(UC)and Crohn’s disease(CD)patients and compared this with HZ incidence in a non-IBD ***:We conducted a retrospective cohort study(GSK study identifier:VEO-000043)of adults aged18 years with UC and CD and without IBD who were identified from claims recorded in a us healthcare database between October 2015 and February *** HZ incidence rates/1,000 person-years(PY)were calculated,and comparisons of HZ incidence rates between UC or CD and non-IBD cohorts were made using adjusted generalized linear ***:The study population comprised a total of 29,928 UC,25,959 CD,and 11,839,329 non-IBD *** overall HZ incidence rates were 13.64/1,000 PY(UC),15.94/1,000 PY(CD),and 7.95/1,000 PY(non-IBD).UC and CD patients had increased HZ incidence rates,with adjusted incidence rate ratios of 1.35(95%confidence interval[CI],1.26–1.44)and 1.66(95%CI,1.56–1.77),respectively,compared with non-IBD *** analysis indicated increased relative rates of HZ in progressively younger age strata in the UC and CD patients compared with non-IBD *** incidence rates were higher in UC and CD patients who had previously received thiopurines or methotrexate,TNF-inhibitors,or corticosteroids than in UC and CD patients who did not take those ***:UC and CD patients had increased HZ incidence rates compared with patients without IBD,demonstrating the importance of HZ prevention in IBD patients.

关键词： ulcerative colitis Crohn’s disease herpes zoster

Tensor Susceptibilities of QCD Vacuum and Parameterized Quark Propagator

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Communications in Theoretical Physics 2008年第3期49卷 717-722页

作者： ZHOU Li-Juan MENG Cheng-Ju PAN Ji-Huan LIU Bao-Rong MA Wei-Xing Collaboration group of Hadron Physics and Non-perturbative QCD study Guangxi University of Technology Liuzhou 545006 China Department of Physics Hechi College Yizhou 546300 China Department of Physics Guangxi University Nanning 530004 China Institute of High Energy Physics the Chinese Academy of Sciences Beijing 100049 China

Based on the parameterized fully dressed quark propagator proposed by us, the tensor susceptibilities of QCD vacuum and quark vacuum condensates are investigated. Our predicted values of the tensor susceptibilities are in agreement with those predicted by many other theoretical models with QCD feature. The results also show that the tensor susceptibility of QCD vacuum strongly depends on flavor of quark but not sensitive to variation of quark vacuum condensates. However, the quark vacuum condensate is very sensitive to the change of cut-off-parameter μ^2 of the integration, that is, it depends on the separation point of perturbative and non-perturbative QCD region. The successful predictions clearly indicate the extensive validity of our parameterized fully dressed quark propagator used here.

关键词： QCD vacuum tensor susceptibilities quark propagator

Utilizing Statistical Semantic Similarity Techniques for Ontology Mapping——with Applications to AEC Standard Models

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Tsinghua Science and Technology 2008年第S1期13卷 217-222页

作者： Chin-Pang Jack Cheng Gloria T. Lau Kincho H. Law Engineering Informatics group Stanford University

The objective of this paper is to introduce three semi-automated approaches for ontology mapping using relatedness analysis techniques. In the architecture, engineering, and construction (AEC) industry, there exist a number of ontological standards to describe the semantics of building models. Although the standards share similar scopes of interest, the task of comparing and mapping concepts among standards is challenging due to their differences in terminologies and perspectives. Ontology mapping is therefore necessary to achieve information interoperability, which allows two or more information sources to exchange data and to re-use the data for further purposes. The attribute-based approach, corpus-based approach, and name-based approach presented in this paper adopt the statistical relatedness analysis techniques to discover related concepts from heterogeneous ontologies. A pilot study is conducted on IFC and CIS/2 ontologies to evaluate the approaches. Preliminary results show that the attribute-based approach outperforms the other two approaches in terms of precision and F-measure.

关键词： ontology mapping similarity analysis information interoperation statistical analysis techniques

Nonlinear Quantum Optical Springs and Their Nonclassical Properties

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Communications in Theoretical Physics 2011年第8期56卷 327-332页

作者： M.J.Faghihi M.K.Tavassoly Atomic and Molecular group Faculty of PhysicsYazd University

The original idea of quantum optical spring arises from the requirement of quantization of the frequency of oscillations in the Hamiltonian of harmonic oscillator. This purpose is achieved by considering a spring whose constant （and so its frequency） depends on the quantum states ofanother system. Recently, it is realized that by the assumption of frequency modulation of ω to ω √1＋ μα＋α the mentioned idea can be established. In the present paper, we generalize the approach of quantum optical spring with particular attention to the dependence or trequency to the intensity of radiation field that naturally observes in the nonlinear coherent states, from which we arrive at a physical system has been called by us as nonlinear quantum optical spring. Then, after the introduction of the generalized tlamiltonian of nonlinear quantum optical spring and it＇s solution, we will investigate the nonclassical properties of the obtained states. Specially, typical collapse and revival in the distribution functions and squeezing parameters, as particular quantum features, will be revealed.

关键词： nonlinear coherent states quantum optical spring nonclassical states

Stress-augmented thermal activation:Tribology feels the force

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Friction 2018年第1期6卷 1-31页

作者： Hugh SPIKES Tribology group Department of Mechanical EngineeringImperial College

In stress-augmented thermal activation, the activation energy barrier that controls the rate of atomic and molecular processes is reduced by the application of stress, with the result that the rate of these processes increases exponentially with applied stress. This concept has particular relevance to Tribology, and since its development in the early twentieth century, it has been applied to develop important models of plastic flow, sliding friction, rheology, wear, and tribochemistry. This paper reviews the development of stress-augmented thermal activation and its application to all of these areas of Tribology. The strengths and limitations of the approach are then discussed and future directions considered. From the scientific point of view, the concept of stress-augmented thermal activation is important since it enables the development of models that describe macroscale tribological performance, such as friction coefficient or tribofilm formation, in terms of the structure and behaviour of individual atoms and molecules. This both helps us understand these processes at a fundamental level and also provides tools for the informed design of lubricants and surfaces.

关键词： stress activation stress augmented thermal activation mechanochemistry friction EHD friction wear Eyring