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arXiv 2017年

作者： Li, Ya Ma, Ai-Jun Rui, Zhou Xiao, Zhen-Jun Department of Physics Institute of Theoretical Physics Nanjing Normal University Nanjing Jiangsu210023 China College of Sciences North China University of Science and Technology Tangshan063009 China Jiangsu Key Laboratory for Numerical Simulation of Large Scale Complex Systems Nanjing Normal University Nanjing Jiangsu210023 China

In this paper, we calculated the branching ratios of the quasi-two-body decays B → ηc(1S, 2S) [ρ(770), ρ(1450), ρ(1700) →]ππ by employing the perturbative QCD (PQCD) approach. The contributions from the P -wave resonances ρ(770), ρ(1450) and ρ(1700) were taken into account. The two-pion distribution amplitude ΦPππ is parameterized by the vector current time-like form factor Fπ to study the considered decay modes. We found that (a) the PQCD predictions for the branching ratios of the considered quasi-two-body decays are in the order of 10−7 ∼ 10−6, while the two-body decay rates B(B → ηc(1S, 2S)(ρ(1450), ρ(1700))) are extracted from those for the corresponding quasi-two-body decays;(b) the whole pattern of the pion form factor-squared |Fπ|2 measured by the BABAR Collaboration could be understood based on our theoretical results;(c) the general expectation based on the similarity between B → ηcππ and B → J/ψππ decays are confirmed: R2(ηc) ≈ 0.45 is consistent with the measured R2(J/ψ) ≈ 0.56 ± 0.09 within errors;and (d) new ratios R3(ηc(1S)) and R4(ηc(2S)) among the branching ratios of the considered decay modes are defined and could be tested by future experiments. Copyright © 2017, The Authors. All rights reserved.

关键词： Hadrons

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Anatomy of Bs → P V decays and effects of next-to-leading order contributions in the perturbative QCD factorization approach

arXiv

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arXiv 2017年

作者： Yan, Da-Cheng Yang, Ping Liu, Xin Xiao, Zhen-Jun Department of Physics Institute of Theoretical Physics Nanjing Normal University Nanjing Jiangsu210023 China School of Physics and Electronic Engineering Jiangsu Normal University Xuzhou221116 China Jiangsu Key Laboratory for Numerical Simulation of Large Scale Complex Systems Nanjing Normal University Nanjing Jiangsu210023 China

In this paper, we will make systematic calculations for the branching ratios and the CP-violating asymmetries of the twenty one B¯s0 → P V decays by employing the perturbative QCD (PQCD) factorization approach. Besides the full leading-order (LO) contributions, all currently known next-to-leading order (NLO) contributions are taken into account. We found numerically that: (a) the NLO contributions can provide ∼ 40% enhancement to the LO PQCD predictions for B(B¯s0 → K0K¯ ∗0) and B(B¯s0 → K±K∗), or a ∼ 37% reduction to B(B¯s0 → π−K∗+);and we confirmed that the inclusion of the known NLO contributions can improve significantly the agreement between the theory and those currently available experimental measurements;(b) the total effects on the PQCD predictions for the relevant B → P transition form factors after the inclusion of the NLO twist-2 and twist-3 contributions is generally small in magnitude: less than 10% enhancement respect to the leading order result;(c) for the "tree" dominated decay B¯s0 → K+ρ− and the "color-suppressed-tree" decay B¯s0 → π0K∗0, the big difference between the PQCD predictions for their branching ratios are induced by different topological structure and by interference effects among the decay amplitude AT,C and AP: constructive for the first decay but destructive for the second one;and (d) for B¯s0 → V (η, η′) decays, the complex pattern of the PQCD predictions for their branching ratios can be understood by rather different topological structures and the interference effects between the decay amplitude A(V ηq) and A(V ηs) due to the η − η′ mixing. Copyright © 2017, The Authors. All rights reserved.

关键词： Forecasting

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A system-of-systems architecture-driven modeling method for combat system effectiveness simulation 2

A system-of-systems architecture-driven modeling method for ...

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2nd Annual IEEE International Symposium on systems Engineering, ISSE 2016

作者： Li, Xiaobo Wang, Weiping Shu, Zhe Zhu, Ning He, Hua Liao, Tianjun College of Information Systems and Management National University of Defense Technology Changsha Hunan410073 China Department of Mathematics and Computer Science University of Antwerp Antwerp2020 Belgium State Key Laboratory of Complex System Simulation Beijing Institute of Systems Engineering Beijing China

ISBN: (纸本)9781509007936

Under the background of system-of-systems (SoS) counterwork, it is more apparent that the simulation modeling of the equipment should be domain-specific, formal, automatic and composable. Current equipment effectiveness simulation modeling approaches are mainly based on the methods and techniques from the modeling and simulation (M&S) community and software engineering community, and they are not capable to satisfy these four requirements systematically. Thus the systems engineering architecture model and domain knowledge should be used to support effectiveness simulation modeling more effectively. In this research, we propose an architecture-driven modeling method which conforms to the principle of architecture-driven development, uses ontology techniques to build equipment SoS architecture model and sub-domain ontology. This method performs architecture driven simulation modeling to realize the transformation from architecture models to simulation model frameworks;employs ontological metamodeling to design domain-specific modeling languages (DSML) based on the comprehensive usage of architecture models, sub-domain ontologies and M&S formalisms;integrates domain-specific simulation models from various domains using the model framework, and supports the composable development of simulation applications. © 2016 IEEE.

关键词： System of systems

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Quasi-two-body decays B(s)→D(ρ(1450), ρ(1700))→Dππ in the perturbative QCD factorization approach

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Physical Review D 2017年第9期96卷 093011-093011页

作者： Ai-Jun Ma Ya Li Wen-Fei Wang Zhen-Jun Xiao Department of Physics and Institute of Theoretical Physics Nanjing Normal University Nanjing Jiangsu 210023 People’s Republic of China Institute of Theoretical Physics Shanxi University Taiyuan Shanxi 030006 People’s Republic of China Jiangsu Key Laboratory for Numerical Simulation of Large Scale Complex Systems Nanjing Normal University Nanjing Jiangsu 210023 People’s Republic of China

By employing a framework for the quasi-two-body decays in the perturbative QCD (PQCD) factorization approach, we calculate the branching ratios of the decays B(s)→D(ρ(1450), ρ(1700))→Dππ with D=(D(s),D¯(s)). The pion vector form factor Fπ, acquired from a BABAR Collaboration analysis of e+e−→π+π−(γ) data, is involved in the two-pion distribution amplitudes ΦππI=1. The PQCD predictions for the branching ratios of the considered quasi-two-body decays are in the range of 10−10–10−4. The PQCD predictions for B(B0→D¯0(ρ0(1450),ρ0(1700))→D¯0π+π−) agree well with the measured values as reported by LHCb if one takes still large theoretical errors into account. Unlike the traditional way of the PQCD approach, one can extract the decay rates for the two-body decays B(s)→D(ρ(1450),ρ(1700)) from the results of the corresponding quasi-two-body decays. The PQCD predictions for B(B(s)→Dρ(1450)) and B(B(s)→Dρ(770)) are similar in magnitude: an interesting relation to be tested by future experimental measurements.

关键词： Electroweak interaction Form factors Particle decays Particle phenomena

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On semilinear Tricomi equations with critical exponents or in two space dimensions

arXiv

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arXiv 2017年

作者： He, Daoyin Witt, Ingo Yin, Huicheng Department of Mathematics and IMS Nanjing University Nanjing210093 China Mathematical Institute University of Göttingen Bunsenstr. 3-5 GöttingenD-37073 Germany School of Mathematical Sciences Jiangsu Provincial Key Laboratory for Numerical Simulation of Large Scale Complex Systems Nanjing Normal University Nanjing210023 China

This paper is a complement of our recent works on the semilinear Tricomi equations in [8] and [9]. For the semilinear Tricomi equation ∂t2u−t∆u = |u|p with initial data (u(0, ·), ∂tu(0, ·)) = (u0, u1), where t ≥ 0, x ∈ Rn (n ≥ 3), p > 1, and ui ∈ C0∞(Rn) (i = 0, 1), we have shown in [8] and [9] that there exists a critical exponent pcrit(n) > 1 such that the solution u, in general, blows up in finite time when 1 crit(n), and there is a global small solution for p > pcrit(n). In the present paper, firstly, we prove that the solution of ∂t2u − t∆u = |u|p will generally blow up for the critical exponent p = pcrit(n) and n ≥ 2, secondly, we establish the global existence of small data solution to ∂t2u − t∆u = |u|p for p > pcrit(n) and n = 2. Thus, we have given a systematic study on the blowup or global existence of small data solution u to the equation ∂t2u − t∆u = |u|p for n ≥ 2.35L70, 35L65, 35L67 Copyright © 2017, The Authors. All rights reserved.

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The view growth pattern of user generated videos on YouTube

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International Journal of u- and e- Service, Science and Technology 2016年第6期9卷 433-444页

作者： Zhou, Renjie Xia, Dongchen Yin, Yuyu Zhang, Jilin Zhang, Wei College of Computer Science and Technology Hangzhou Dianzi University Hangzhou China Key Laboratory Complex System Modeling and Simulation Ministry of Education Hangzhou China

With the rapid development of social media, video sharing sites like YouTube are getting more and more attention. Discovering the view growth pattern have become interesting topics for researchers as well as advertisers, media companies. In this paper, we analyze two aspects about video view growth pattern of YouTube videos. Firstly, the pattern of aggregated view is studied. It is found that the aggregated view rate peaks in the first few days, and falls quickly in the following days, and then decrease slowly during the consecutive weeks. Finally, the view rate tends to be a constant on the long run. The aggregated view count after a period of two months can be fitted with a linear line. Secondly, the view growth pattern of individual video is explored. The results indicate that the majority of videos peak at the very beginning of videos’ lifetime, and the category of view sources causes the peak is different. The view count of individual video and the view count from each source item also stabilize after a period of two months, and we finally show the referring time and active period of each source item. © 2016 SERSC.

关键词： Growth rate

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Toward activity mapping for Artifact-Centric business process

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International Journal of u- and e- Service, Science and Technology 2016年第6期9卷 421-432页

作者： Yin, Yuyu Zhu, Zhengshuang Gao, Min Song, Aihua College of Electrical Engineering Zhejiang University HangzhouZhejiang310027 China School of Computer Science and Technology Hangzhou Dianzi University HangzhouZhejiang310018 China Key Laboratory of Complex Systems Modeling and Simulation Ministry of Education HangzhouZhejiang310018 China

The existing method of task mapping between process models is mostly based on the similarity of labels to get the similarity between tasks, which is affected by a single factor and easy to cause errors. This paper proposes a task mapping method for Artifact-Centric business process analyzes the data operation in business process execution. At first we add the description of data operation to EZ-Flow model. Secondly select the similar artifact attributes of the two business artifact by whole artifacts similarity calculation and based them to calculate two tasks’ similarity by label similarity, artifact operation similarity and context similarity calculations. Finally, the task mapping comes from the optimal selection of tasks’ similarities. Experimental results verify the effectiveness of the method, and show that the method reflects the data operation characteristics of business process model, as artifact task mapping of the process model provides a feasible method. © 2016 SERSC.

关键词： Mapping

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Virtual Page Behavior Based Page Management Policy for Hybrid Main Memory in Cloud Computing

Virtual Page Behavior Based Page Management Policy for Hybri...

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International Conference on Mobile Ad-hoc and Sensor Networks, MSN

作者： Jie Huang Xuan Zhang Guangjie Han Gangyong Jia Huizi Liyou Jian Wan Key Laboratory of Complex Systems Modeling and Simulation Ministry of Education Hangzhou China Department of Computer Science and Technology Hangzhou Dianzi University Hangzhou China Department of Information & Communication Systems Hohai University Chanqzhou China School of Information and Electronic Engineering Zhejiang University of Science and Technology Hangzhou

ISBN: (纸本)9781509056972

A new generation memory, Non-Volatile Memory (NVM), such as Phase-Change Memory (PCM), has been adopted together with DRAM in the main memory to form the hybrid main memory for low energy consumption and high capacity. The biggest challenge of hybrid memory is how to decrease the average memory access cost for the higher cost of NVM's read/write operation. Currently, most researches are based on migration. However, the page migration itself is a high cost operation. And the migration based policy produces many migration operations, which induces high cost in memory access. Therefore, in order to decrease the cost, we present a virtual page behavior based page management policy (VBPM) in this paper. According to the virtual pages' behavior, we allocate virtual pages into DRAM or PCM physical pages correspondingly. The whole process is migration independent. The experimental results show our VBPM decreases the average memory access time by 24%, moreover, VBPM improves real-time performance in critical path.

关键词： Phase change materials Random access memory Memory management Algorithm design and analysis Resource management Nonvolatile memory Cloud computing

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A system-of-systems architecture-driven modeling method for combat system effectiveness simulation

A system-of-systems architecture-driven modeling method for ...

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IEEE International Symposium on systems Engineering (ISSE)

作者： Xiaobo Li Weiping Wang Zhe Shu Ning Zhu Hua He Tianjun Liao Beijing Institute of System Engineering Beijing CN College of Information Systems and Management National University of Defense Technology Changsha Hunan P. R. China State Key Laboratory of Complex System Simulation Beijing Institute of Systems engineering Beijing China

ISBN: (纸本)9781509007943

Under the background of system-of-systems (SoS) counterwork, it is more apparent that the simulation modeling of the equipment should be domain-specific, formal, automatic and composable. Current equipment effectiveness simulation modeling approaches are mainly based on the methods and techniques from the modeling and simulation (M&S) community and software engineering community, and they are not capable to satisfy these four requirements systematically. Thus the systems engineering architecture model and domain knowledge should be used to support effectiveness simulation modeling more effectively. In this research, we propose an architecture-driven modeling method which conforms to the principle of architecture-driven development, uses ontology techniques to build equipment SoS architecture model and sub-domain ontology. This method performs architecture driven simulation modeling to realize the transformation from architecture models to simulation model frameworks; employs ontological metamodeling to design domain-specific modeling languages (DSML) based on the comprehensive usage of architecture models, sub-domain ontologies and M&S formalisms; integrates domain-specific simulation models from various domains using the model framework, and supports the composable development of simulation applications.

关键词： Computational modeling Ontologies Computer architecture Analytical models Mathematical model

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Development of database of real-world diesel vehicle emission factors for China

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Journal of Environmental Sciences 2015年第5期27卷 209-220页

作者： Xianbao Shen Zhiliang Yao Qiang Zhang David Vance Wagner Hong Huo Yingzhi Zhang Bo Zheng Kebin He State Key Joint Laboratory of Environment Simulation and Pollution Control School of Environment Tsinghua University School of Food and Chemical Engineering Beijing Technology and Business University Ministry of Education Key Laboratory for Earth System Modeling Center for Earth System Science Tsinghua University International Council on Clean Transportation (ICCT) Institute of Energy Environment and Economy Tsinghua University State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex Tsinghua University

A database of real-world diesel vehicle emission factors, based on type and technology, has been developed following tests on more than 300 diesel vehicles in China using a portable emission measurement system. The database provides better understanding of diesel vehicle emissions under actual driving conditions. We found that although new regulations have reduced real-world emission levels of diesel trucks and buses significantly for most pollutants in China, NOx emissions have been inadequately controlled by the current standards, especially for diesel buses, because of bad driving conditions in the real world. We also compared the emission factors in the database with those calculated by emission factor models and used in inventory studies. The emission factors derived from COPERT（Computer Programmer to calculate Emissions from Road Transport） and MOBILE may both underestimate real emission factors, whereas the updated COPERT and PART5（Highway Vehicle Particulate Emission modeling Software） models may overestimate emission factors in China. Real-world measurement results and emission factors used in recent emission inventory studies are inconsistent,which has led to inaccurate estimates of emissions from diesel trucks and buses over recent years. This suggests that emission factors derived from European or US-based models will not truly represent real-world emissions in China. Therefore, it is useful and necessary to conduct systematic real-world measurements of vehicle emissions in China in order to obtain the optimum inputs for emission inventory models.

关键词： Diesel vehicle Emission factor Portable emission measurement system Database China

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