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conditional Congruence Closure over Uninterpreted and Interpreted Symbols

Journal of Systems Science & Complexity 2019年第1期32卷 317-355页

作者： KAPUR Deepak Department of Computer Science University of New Mexico

A framework for generating congruence closure and conditional congruence closure of ground terms over uninterpreted as well as interpreted symbols satisfying various properties is proposed. It is based on some of the key concepts from Kapur's congruence closure algorithm(RTA97)for ground equations based on introducing new symbols for all nonconstant subterms appearing in the equation set and using ground completion on uninterpreted constants and puri?ed equalities over interpreted symbols belonging to different theories. In the original signature, the resulting rewrite systems may be nonterminating but they still generate canonical forms. A byproduct of this framework is a constant Horn completion algorithm using which ground canonical Horn rewrite systems can be generated for conditional ground *** effcient algorithms for generating congruence closure of conditional and unconditional equations on ground terms over uninterpreted symbols are presented. The complexity of the conditional congruence closure is shown to be O(n*log(n)), which is the same as for unconditional ground *** proposed algorithm is motivated by our attempts to generate effcient and succinct interpolants for the quanti?er-free theory of equality over uninterpreted function symbols which are often a conjunction of conditional equations and need additional simpli?cation. A completion algorithm to generate a canonical conditional rewrite system from ground conditional equations is also presented. The framework is general and ?exible and is used later to develop congruence closure algorithms for cases when function symbols satisfy simple properties such as commutativity, nilpotency, idempotency and identity as well as their combinations. Interesting outcomes include algorithms for canonical rewrite systems for ground equational and conditional theories on uninterpreted and interpreted symbols leading to generation of canonical forms for ground terms, constrained terms and Horn equat

关键词： Completion congruence closure conditional congruence closure intepreted symbols rewrit-ing uninterpreted symbols

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conditional privacy protection authentication scheme based on bilinear pairings for VANET

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The Journal of China Universities of Posts and Telecommunications 2020年第1期27卷 62-71页

作者： Song Cheng Gu Xin'an Ping Yuan Zhang Yadong School of Computer Science and Technology Henan Polytechnic UniversityJiaozuo 454000China School of Information Engineering Xuchang UniversityXuchang 461000China

To solve the problem of security and efficiency of anonymous authentication in the vehicle Ad-hoc network(VANET), a conditional privacy protection authentication scheme for vehicular networks is proposed based on bilinear pairings. In this scheme, the tamper-proof device in the roadside unit(RSU) is used to complete the message signature and authentication process together with the vehicle, which makes it more secure to communicate between RSU and trusted authority(TA) and faster to update system parameters and revoke the vehicle. And this is also cheaper than installing tamper-proof devices in each vehicle unit. Moreover, the scheme provide provable security proof under random oracle model(ROM), which shows that the proposed scheme can meet the security requirements such as conditional privacy, unforgeability, traceability, etc. And the results of simulation experiment demonstrate that this scheme not only of achieves high efficiency, but also has low message loss rate.

关键词： VANET anonymous authentication bilinear pairings conditional privacy protection

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conditional survival in patients with gallbladder cancer

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Chinese Journal of Cancer 2017年第12期36卷 744-756页

作者： Yi-Jun Kim Kyubo Kim Department of Radiation Oncology Ewha Womans University College of Medicine1071 Anyangcheon.roYangcheon.guSeoul 07985Republic of Korea

Background: conditional survival(CS) has been established as a clinically relevant prognostic factor for cancer survivors, and the CS in gallbladder(GB) cancer has not yet been fully evaluated. In this study, we evaluated the cancerspecific CS rate and cancer-specific survival(CSS) rate in patients with GB cancer at multiple time points and investigated prognostic factors which affect cancer-specific CS rate to provide more accurate survival ***: Between 2004 and 2013, a total of 9760 patients with GB cancer were identified from the Surveillance,Epidemiology, and End Results(SEER) data. The 3-year cancer-specific CS rate was calculated using the covariateadjusted survival function in the Cox model for each year since diagnosis, and the results were analyzed together with the adjusted CSS rates at the same time points. Cox proportional hazards regression was performed to ascertain the individual contribution of factors associated with CSS rate at diagnosis and cancer-specific CS rates at 1,3, and 5 years after ***: The adjusted 5-year CSS rate was 26.1 %. The adjusted 3-year cancer-specific CS rates at 1,2,3,4, and 5 years after diagnosis were 55.5,72.2,81.5,86.8, and 90.5%, respectively. At the time of diagnosis, age, race, histology, grade,T, N, and M categories, surgery, radiotherapy, insurance status, and marriage status were significant prognostic factors of CSS. Five years after diagnosis, however,T and M categories were significant prognostic factors for survivors(P = 0.007 and P = 0.009, respectively), whereas surgery and radiotherapy were ***: T and M categories were significant prognostic factors even 5 years after the initial diagnosis, whereas local treatments at the time of diagnosis were not, suggesting that patients with GB cancer at high risks might need further adjuvant therapy after primary treatments. The combined analysis of CSS and cancer-specific CS rates offered more accurate survival information for pa

关键词： Gallbladder cancer conditional survival SEER

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Multi-objective interval prediction of wind power based on conditional copula function

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Journal of Modern Power Systems and Clean Energy 2019年第4期7卷 802-812页

作者： Gang ZHANG Zhixuan LI Kaoshe ZHANG Lei ZHANG Xia HUA Yongqing WANG Institute of Water Resources and Hydro-Electric Engineering Xi’an University of TechnologyXi’an 710048China State Grid Shaanxi Baoji Electric Power Company Baoji 721000China State Grid Gansu Electric Power Company Gansu Electric Power Research InstituteLanzhou 730050China State Grid Shaanxi Electric Power Company Shaanxi Electric Power Research InstituteXi’an 710054China

Interval prediction of wind power,which features the upper and lower limits of wind power at a given confidence level,plays a significant role in accurate prediction and stability of the power grid integrated with wind ***,the conventional methods of interval prediction are commonly based on a hypothetic probability distribution function,which neglects the correlations among various variables,leading to the decrease of prediction ***,we improve the multi-objective interval prediction based on the conditional copula function,through which we can fully utilize the correlations among variables to improve prediction accuracy without an assumed probability distribution *** use the multi-objective optimization method of nondominated sorting genetic algorithm-II(NSGA-II)to obtain the optimal solution *** particular best solution is weighted by the prediction interval average width(PIAW)and prediction interval coverage probability(PICP)to pick the optimized solution in practical ***,we apply the proposed method to three wind power plants in different cities in China as examples forvalidation and obtain higher prediction accuracy compared with other methods,i.e.,relevance vector machine(RVM),artificial neural network(ANN),and particle swarm optimization kernel extreme learning machine(PSO-KELM).These results demonstrate the superiority and practicability of this method in interval prediction of wind power.

关键词： Wind power prediction Interval prediction conditional copula function Empirical distribution function Multi-objective optimization algorithm

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The application of the orthogonal conditional nonlinear optimal perturbations method to typhoon track ensemble forecasts

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Science China Earth Sciences 2019年第2期62卷 376-388页

作者： Zhenhua HUO Wansuo DUAN National Meteorological Center China Meteorological Administration State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric PhysicsChinese Academy of Sciences University of Chinese Academy of Sciences

The orthogonal conditional nonlinear optimal perturbations (CNOPs) method, orthogonal singular vectors (SVs)method and CNOP+SVs method, which is similar to the orthogonal SVs method but replaces the leading SV (LSV) with the first CNOP, are adopted in both the Lorenz-96 model and Pennsylvania State University/National Center for Atmospheric Research (PSU/NCAR) Fifth-Generation Mesoscale Model (MM5) for ensemble forecasts. Using the MM5, typhoon track ensemble forecasting experiments are conducted for strong Typhoon Matsa in 2005. The results of the Lorenz-96 model show that the CNOP+SVs method has a higher ensemble forecast skill than the orthogonal SVs method, but ensemble forecasts using the orthogonal CNOPs method have the highest forecast skill. The results from the MM5 show that orthogonal CNOPs have a wider horizontal distribution and better describe the forecast uncertainties compared with SVs. When generating the ensemble mean forecast, equally averaging the ensemble members in addition to the anomalously perturbed forecast members may contribute to a higher forecast skill than equally averaging all of the ensemble members. Furthermore, for given initial perturbation amplitudes, the CNOP+SVs method may not have an ensemble forecast skill greater than that of the orthogonal SVs method, but the orthogonal CNOPs method is likely to have the highest forecast skill. Compared with SVs, orthogonal CNOPs fully consider the influence of nonlinear physical processes on the forecast results; therefore, considering the influence of nonlinearity may be important when generating fast-growing initial ensemble perturbations. All of the results show that the orthogonal CNOP method may be a potential new approach for ensemble forecasting.

关键词： Ensemble forecasts Initial perturbation conditional nonlinear optimal perturbation Singular vector Typhoon track

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On tail behavior of nonlinear autoregressive functional conditional heteroscedastic model with heavy-tailed innovations

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Science China Mathematics 2005年第9期48卷 1169-1181页

作者： PAN Jiazhu WU Guangxu LMAM and School of Mathematical Sciences Peking University Beijing 100871 China LMAM and School of Mathematical Sciences Peking University Beijing 100871 China

We study the tail probability of the stationary distribution of nonparametric nonlinear autoregressive functional conditional heteroscedastic (NARFCH) model with heavytailed innovations. Our result shows that the tail of the stationary marginal distribution of an NARFCH series is heavily dependent on its conditional variance. When the innovations are heavy-tailed, the tail of the stationary marginal distribution of the series will become heavier or thinner than that of its innovations. We give some specific formulas to show how the increment or decrement of tail heaviness depends on the assumption on the conditional variance function. Some examples are given.

关键词： tail probability, stationary distribution, nonlinear AR model, nonlinear autoregressive functional conditional heteroscedastic model, heavy-tailed distribution.

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Continuous Probabilistic SLAM Solved via Iterated conditional Modes

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International Journal of Automation and computing 2019年第6期16卷 838-850页

作者： J.Gimenez A.Amicarelli J.M.Toibero F.di Sciascio R.Carelli Automatics Institute(INAUT) National University of San Juan-CONICET

This article proposes a simultaneous localization and mapping(SLAM) version with continuous probabilistic mapping(CPSLAM), i.e., an algorithm of simultaneous localization and mapping that avoids the use of grids, and thus, does not require a discretized environment. A Markov random field(MRF) is considered to model this SLAM version with high spatial resolution maps. The mapping methodology is based on a point cloud generated by successive observations of the environment, which is kept bounded and representative by including a novel recursive subsampling method. The CP-SLAM problem is solved via iterated conditional modes(ICM), which is a classic algorithm with theoretical convergence over any MRF. The probabilistic maps are the most appropriate to represent dynamic environments, and can be easily implemented in other versions of the SLAM problem, such as the multi-robot version. Simulations and real experiments show the flexibility and excellent performance of this proposal.

关键词： Probabilistic simultaneous localization and mapping(SLAM) dynamic obstacles Markov random fields(MRF) iterated conditional modes(ICM) kernel estimator

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Ensemble Forecasts of Tropical Cyclone Track with Orthogonal conditional Nonlinear Optimal Perturbations

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Advances in Atmospheric Sciences 2019年第2期36卷 231-247页

作者： Zhenhua HUO Wansuo DUAN Feifan ZHOU National Meteorological Center China Meteorological Administration State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric Physics Chinese Academy of Sciences University of Chinese Academy of Sciences Laboratory of Cloud-Precipitation Physics and Severe Storms Institute of Atmospheric PhysicsChinese Academy of Sciences

This paper preliminarily investigates the application of the orthogonal conditional nonlinear optimal perturbations(CNOPs)–based ensemble forecast technique in MM5(Fifth-generation Pennsylvania State University–National Center for Atmospheric Research Mesoscale Model). The results show that the ensemble forecast members generated by the orthogonal CNOPs present large spreads but tend to be located on the two sides of real tropical cyclone(TC) tracks and have good agreements between ensemble spreads and ensemble-mean forecast errors for TC tracks. Subsequently, these members reflect more reasonable forecast uncertainties and enhance the orthogonal CNOPs–based ensemble-mean forecasts to obtain higher skill for TC tracks than the orthogonal SVs(singular vectors)–, BVs(bred vectors)– and RPs(random perturbations)–based ones. The results indicate that orthogonal CNOPs of smaller magnitudes should be adopted to construct the initial ensemble perturbations for short lead–time forecasts, but those of larger magnitudes should be used for longer lead–time forecasts due to the effects of nonlinearities. The performance of the orthogonal CNOPs–based ensemble-mean forecasts is case-dependent,which encourages evaluating statistically the forecast skill with more TC cases. Finally, the results show that the ensemble forecasts with only initial perturbations in this work do not increase the forecast skill of TC intensity, which may be related with both the coarse model horizontal resolution and the model error.

关键词： ensemble forecast initial perturbation conditional nonlinear optimal perturbation tropical cyclone

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Simultaneous Estimation of Multiple conditional Regression Quantiles

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Acta Mathematicae Applicatae Sinica 2020年第2期36卷 448-457页

作者： Yan-ke WU Ya-nan HU Jian ZHOU Mao-zai TIAN Faculty of Mathematics and Computer Science Guangdong Ocean UniversityZhanjiang 524088China Center for Applied Statistics School of StatisticsRenmin University of ChinaBeijing 100872China School of Statistics Lanzhou University of Finance and EconomicsLanzhou 730101China School of Statistics and Information Xinjiang University of Finance and EconomicsUrumqi 830012China Business School Zhengzhou UniversityZhenzhou 450001China China Academy of Transportation Sciences Beijing 100029China

In this article, we put forward a new approach to estimate multiple conditional regression quantiles simultaneously. Unlike the double summation method in most of the literatures, our proposed model allows continuous variety for the quantile level over(0,1). As a result, all the quantile curves can be obtained via a 2-dimensional surface simultaneously. Most importantly, the proposed minimizing criterion can be readily transformed to a linear programming problem. We use tensor product bi-linear quantile smoothing B-splines tofit it. The asymptotic property of the estimator is derived and a real data set is analyzed to demonstrate the proposed method.

关键词： Simultaneous Estimation conditional Regression Quantiles B-spline Tensor Product

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Establishment of Smad2 conditional gene targeting mice based on the Cre-LoxP system

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Science China(Life Sciences) 2002年第2期45卷 129-137页

作者：周江黄培堂程萱黄翠芬孙彦洵杨晓 1. Genetic Laboratory of Development and Diseases Institute of Biotechnology 100071 Beijing China

Smads is a new gene family in transforming growth factor-β(TGF-β) signaling pathway. Smad2 mutated in multiple human tumors and may be a candidate tumor suppressor gene. Targeted disruption of murine Smad2 gene resulted in embryonic lethality at E6.5. To study the function of Smad2 in vertebrate organgenesis and tumorigenesis, we constructed the Smad2 conditional targeting vector in which two LoxP sequences were placed to flank the sequences encoding the C terminal functional domain of Smad2. The validity of the LoxP sites in the targeting construct was tested in E. coli that express the Cre recombinase constitutively. The vector was electroporated into ES cells and 3 targeted ES cell clones were obtained by Southern blot screening. Targeted ES cells were introduced into C57BL/6J blastocysts by microinjection to generate germ-line chimeras. Genotyping analysis showed that 2 progeny among these chimeras carried the Smad2 conditional targeted allele. The establishment of Smad2 conditional gene targeting mouse has laid a solid foundation for producing the tissue specific Smad2 gene knockout mice.

关键词： Smad2, embryonic stem cell, Cre-LoxP system, conditional gene knockout.

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