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Grids of rotating stellar models with masses between 1.0 and 3.0 M_⊙

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Research in Astronomy and Astrophysics 2013年第5期13卷 579-592页

作者： Wu-Ming Yang Shao-Lan bi xiang-Cun Meng Department of Astronomy Beijing Normal University School of Physics and Chemistry Henan Polytechnic University

We calculated a grid of evolutionary tracks of rotating models with masses between 1.0 and 3.0 M⊙ and resolution δM 〈 0.02 M⊙, which can be used to study the effects of rotation on stellar evolution and on the characteristics of star clusters. The value of ～ 2.05 Me is a critical mass for the effects of rotation on stellar struc- ture and evolution. For stars with M 〉 2.05 Me, rotation leads to an increase in the convective core and prolongs their lifetime on the main sequence （MS）; rotating mod- els evolve more slowly than non-rotating ones; the effects of rotation on the evolution of these stars are similar to those of convective core overshooting. However for stars with 1.1 〈 M/M⊙ 〈 2.05, rotation results in a decrease in the convective core and shortens the duration of the MS stage; rotating models evolve faster than non-rotating ones. When the mass has values in the range ～ 1.7 - 2.0 M⊙, the mixing caused by rotationally induced instabilities is not efficient; the hydrostatic effects dominate pro- cesses associated with the evolution of these stars. For models with masses between about 1.6 and 2.0 M⊙, rotating models always exhibit lower effective temperatures than non-rotating ones at the same age during the MS stage. For a given age, the lower the mass, the smaller the change in the effective temperature. Thus rotations could lead to a color spread near the MS turnoff in the color-magnitude diagram for intermediate-age star clusters.

关键词： stars: evolution -- stars: rotation m stars: interiors

Low-cost adaptive square-root cubature Kalman filter forsystems with process model uncertainty

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Journal of Systems Engineering and Electronics 2016年第5期27卷 945-953页

作者： an zhang shuida bao wenhao bi yuan yuan School of Eelectronics and Information Northwestern Polytechnical University Xi’an 710072 China

A novel low-cost adaptive square-root cubature Kalmanfilter （LCASCKF） is proposed to enhance the robustness of processmodels while only increasing the computational load *** is well-known that the Kalman filter cannot handle uncertainties ina process model, such as initial state estimation errors, parametermismatch and abrupt state changes. These uncertainties severelyaffect filter performance and may even provoke divergence. Astrong tracking filter （STF）, which utilizes a suboptimal fading factor,is an adaptive approach that is commonly adopted to solvethis problem. However, if the strong tracking SCKF （STSCKF）uses the same method as the extended Kalman filter （EKF） tointroduce the suboptimal fading factor, it greatly increases thecomputational load. To avoid this problem, a low-cost introductorymethod is proposed and a hypothesis testing theory is applied todetect uncertainties. The computational load analysis is performedby counting the total number of floating-point operations and it isfound that the computational load of LCASCKF is close to that ofSCKF. Experimental results prove that the LCASCKF performs aswell as STSCKF, while the increase in computational load is muchlower than STSCKF.

关键词： square-root cubature Kalman filter strong tracking filter,robustness computational load.

Review on lithium metal anodes towards high energy density batteries

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Green Energy & Environment 2023年第6期8卷 1509-1530页

作者： Jun-Fan Ding Yu-Tong zhang Rui Xu Rui zhang Ye Xiao Shuo zhang Chen-Xi bi Cheng Tang Rong xiang Ho Seok Park Qiang zhang Jia-Qi Huang School of Materials Science and Engineering Beijing Institute of TechnologyBeijing100081China Advanced Research Institute of Multidisciplinary Science Beijing Institute of TechnologyBeijing100081China School of Chemical Engineering and Advanced Materials The University of AdelaideAdelaideSA5005 Australia Department of Mechanical Engineering The University of TokyoTokyo113-8656Japan State Key Laboratory of Fluid Power and Mechatronic Systems School of Mechanical EngineeringZhejiang UniversityHangzhou310027China School of Chemical Engineering Sungkyunkwan UniversitySuwon440-746Republic of Korea Department of Chemical Engineering Tsinghua UniversityBeijing100084China

Lithium metal anode(LMA) is a promising candidate for achieving next-generation high-energy-density batteries due to its ultrahigh theoretical capacity and most negative electrochemical potential. However, the practical application of lithium metal battery(LMB) is largely retarded by the instable interfaces, uncontrolled dendrites, and rapid capacity deterioration. Herein, we present a comprehensive overview towards the working principles and inherent challenges of LMAs. Firstly, we diligently summarize the intrinsic mechanism of Li stripping and plating process. The recent advances in atomic and mesoscale simulations which are crucial in guiding mechanism study and material design are also summarized. Furthermore, the advanced engineering strategies which have been proved effective in protecting LMAs are systematically reviewed, including electrolyte optimization, artificial interface, composite/alloy anodes and so on. Finally, we highlight the current limitations and promising research directions of LMAs. This review sheds new lights on deeply understanding the intrinsic mechanism of LMAs, and calls for more endeavors to realize practical Li metal batteries.

关键词： Lithium metal anode Solid electrolyte interphase Advanced electrolytes Artificial interface Composite anodes Theoretical simulations

Numerical simulation of aircraft arresting process with an efficient full-scale rigid-flexible coupling dynamic model

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Chinese Journal of Aeronautics 2024年第5期37卷 586-602页

作者： Haoyuan SHAO Daochun LI Zi KAN Lanxi bi Zhuoer YAO Jinwu xiang School of Aeronautic Science and Engineering Beihang UniversityBeijing 100191China Tianmushan Laboratory Hangzhou 310023China

The arresting process of carrier-based aircraft is widely recognized as a challenging task,characterized by the highest accident rate among all carrier-based aircraft *** simulation plays a crucial role in assessing the intricate responses of the arresting process,favoring the design of carrier-based *** efficient and accurate rigid-flexible coupling model for analyzing the dynamic response of the arresting process is *** combining the dynamic characteristics of airframe,landing gear,arresting hook and arresting gear system,the rigid-flexible coupling dynamic model is established to reflect the relative motion of the coupling parts and arresting *** dynamic model is verified through simulations of landing gear landing drops and by comparing the arresting simulation results with corresponding data in the US military ***,simulations of the arresting process under different off-center distance and aircraft yaw angle are conducted to obtain the dynamic response of the aircraft during the arresting *** result indicates that the rigid-flexible coupling dynamic model proposed is effective for analyzing the arresting dynamics response of carrier-based *** axial force of the arresting cable on both sides of the hook engagement point,pitch and yaw angle of aircraft are inconsistent under yaw and off-center *** analysis method and obtained results provide valuable references for assessing the dynamic responses of carrier-based aircraft during arresting process and offer valuable in-sights in the design of carrier-based aircraft.

关键词： Carrier-based aircraft Deck landing Rigid-flexible coupling dynamic model Finite element method Dynamic analysis

Pattern Mining in Linked Data by Edge-Labeling

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Tsinghua Science and Technology 2016年第2期21卷 168-175页

作者： xiang zhang Wenyao Cheng School of Computer Science and Engineering Southeast UniversityNanjing 210096China.

Link patterns are consensus practices characterizing how different types of objects are typically interlinked in linked data. Mining link patterns in large-scale linked data has been inefficient due to the computational complexity of mining algorithms and memory limitations. To improve scalability, partitioning strategies for pattern mining have been proposed. But the efficiency and completeness of mining results are still under discussion. In this paper we propose a novel partitioning strategy for mining link patterns in large-scale linked data, in which linked data is partitioned according to edge-labeling rules： Edges are grouped into a primary multi-partition according to edge labels. A feedback mechanism is proposed to produce a secondary bi-partition according to a quick mining process. Local discovered link patterns in partitions are then merged into global patterns. Experiments show that our partition strategy is feasible and efficient.

关键词： link pattern labeling partitioning scalability evaluation

Specifying redundancy tactics as crosscutting concerns using aspect-oriented modeling

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Frontiers of Computer Science 2014年第6期8卷 977-995页

作者： xiang QIU Li zhang State Key Laboratory of Software Development Environment Beihang University Beijing 100191 China

Various redundancy tactics can be modeled at the design stage of safety-critical systems thereby providing a set of fault-tolerance guidelines for subsequent development activities. However, existing approaches usually interweave redundancy tactics into the functional models making them complex and cluttered; the maintenance of such models is time-consuming and error-prone. To address this problem, we provide a modeling approach to separate the redundancy tactics from the base functional models using aspect-oriented modeling. More specifically, the conceptual models of the redundancy tactics and their semantic constraints are first defined for deriving the relevant aspects. Subsequently, a UML profile is proposed to specify the tactic aspects followed by mapping these concepts to the corresponding concepts of aspect-oriented modeling based on pre-defined principles. In accordance with our proposed profile, reuse directives are applied to handle the overlap of structural features between redundancy tactics and other kinds of tactic. Based on our tactic aspects and their configured attributes, a weaving algorithm is proposed to associate the tactic aspects with the base functional models. The proposed approach is compared with a traditional tactic modeling approach using two safety-critical systems, revealing that： 1） our approach significantly reduces the number of extra model elements needed in the tactic design stage; 2） our approach can largely avoid the impact of changing of the base functional model as the model evolves.

关键词： redundancy tactic, aspect-oriented modeling, weaving algorithm reuse directives

Design of passive fault-tolerant flight controller against actuator failures

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Chinese Journal of Aeronautics 2015年第1期28卷 180-190页

作者： Yu xiang zhang Youmin Department of Mechanical and Industrial Engineering Concordia University

The problem of designing passive fault-tolerant flight controller is addressed when the normal and faulty cases are prescribed. First of all, the considered fault and fault-free cases are formed by polytopes. As considering that the safety of a post-fault system is directly related to the maximum values of physical variables in the system, peak-to-peak gain is selected to represent the relationships among the amplitudes of actuator outputs, system outputs, and reference commands. Based on the parameter dependent Lyapunov and slack methods, the passive fault-tolerant flight controllers in the absence/presence of system uncertainty for actuator failure cases are designed, respectively. Case studies of an airplane under actuator failures are carried out to validate the effectiveness of the proposed approach

关键词： actuator tolerant uncertainty prescribed addressed nominal matrices validate outputs designing

Prognostic impact of metastatic lymph node ratio in advanced gastric cancer from cardia and fundus

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World Journal of Gastroenterology 2008年第27期14卷 4383-4388页

作者： Chang-Ming Huang bi-Juan Lin Hui-Shan Lu xiang-Fu zhang Ping Li Jian-Wei Xie Department of Oncology Affiliated Union Hospital of Fujian Medical University Fuzhou 350001 Fujian Province China

AIM: To investigate the prognostic impact of the metastatic lymph node ratio (MLR) in advanced gastric cancer from the cardia and fundus. METHODS: Two hundred and thirty-six patients with gastric cancer from the cardia and fundus who underwent D2 curative resection were analyzed ret- rospectively. The correlations between MLR and the total lymph nodes, positive nodes and the total lymph nodes were analyzed respectively. The influence of MLR on the survival time of patients was determined with univariate Kaplan-Meier survival analysis and mul- tivariate Cox proportional hazard model analysis. And the multiple linear regression was used to identify the relation between MLR and the 5-year survival rate of the patients. RESULTS: The MLR did not correlate with the total lymph nodes resected (r = -0.093, P = 0.057). The 5-year overall survival rate of the whole cohort was 37.5%. Kaplan-Meier survival analysis identified that the following eight factors influenced the survival time of the patients postoperatively: gender (χ2 = 4.26, P = 0.0389), tumor size (χ2 = 18.48, P < 0.001), Borrmann type (χ2 = 7.41, P = 0.0065), histological grade (χ2 = 5.07, P = 0.0243), pT category (χ2 = 49.42, P < 0.001), pN category (χ2 = 87.7, P < 0.001), total number of re- trieved lymph nodes (χ2 = 8.22, P = 0.0042) and MLR (χ2 = 34.3, P < 0.001). Cox proportional hazard model showed that tumor size (χ2 = 7.985, P = 0.018), pTcategory (χ2 = 30.82, P < 0.001) and MLR (χ2 = 69.39, P < 0.001) independently influenced the prognosis. A linear correlation between MLR and the 5-year survival was statistically significant based on the multiple lin- ear regression (β = -0.63, P < 0.001). Hypothetically, the 5-year survival would surpass 50% when MLR was lower than 10%. CONCLUSION: The MLR is an independent prognostic factor for patients with advanced gastric cancer from the cardia and fundus. The decrease of MLR due to adequate number of total resected lymph nodes can improve the survival.

关键词： Lymph node metastasis Metastatic lymph node ratio Lymphadenectomy Prognosis

Types and microbial genesis of carbonate microbodies in Zoophycos from the Pennsylvanian to Cisuralian Taiyuan Formation in North China

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Journal of Palaeogeography 2018年第3期7卷 283-294页

作者： Hui-Bo Song xiang-Yu zhang Shun-Xi Liu bin hu Rui-Rui Guo Yu-Jun bi School of Resource and Environment Henan Polytechnic UniversityJiaozuo 454000Henan ProvinceChina. Collaborative Innovation Center of Coalbed Methane and Shale Gas for Central Plains Economic Region of Henan Province Jiaozuo 454000Henan ProvinceChina. Key Laboratory of biogenic Traces and Sedimentary Minerals of Henan Province Jiaozuo 454000Henan ProvinceChina. Coal Mining and Dressing Department Changzhi Polytechnic CollegeChangzhi 046000Shanxi ProvinceChina.

Many kinds of ichnofossil Zoophycos occur commonly in the carbonate rocks of Pennsylvanian to Cisuralian Taiyuan Formation in North China. In this study, carbonate microbodies types were identified in four differently-colored fillings of Zoophycos using scanning electron microscopy （SEM） and energy dispersive spectroscopy （EDS）. Based on the morphologic characteristics, these carbonate microbodies can be divided into three groups, i.e., spheroids, framboids and rhabditiforms. According to the structural features of surface and individual or aggregate morphologies, the three groups can be further subdivided into thirteen types：（1） smooth spheroids; （2） spheroids with tiny thorns; （3） spheroids with a finely granulated surface; （4） spheroids with a flocculent surface; （5） spheroids with a vermiform surface; （6） framboid monomers; （7） framboid colonies; （8） linear smooth rhabditiform bodies; （9） smooth rhabditiform bodies with expanding ends; （10） biserial rhabditiform bodies; （11） spiral rhabditiform bodies; （12） thorny rhabditiform bodies; and （13） branched rhabditiform bodies. This paper not only describes the morphology, composition and occurrence of the various carbonate microbodies, but also discusses their possible microbial genesis, as follows：（1） carbonate spherical microbodies most likely were generated after globular bacterial cells had been fully displaced by minerals; （2） framboid monomers and colonies corresponding to the morphology of biogenic strawberry （or raspberry） pyrite, with their appearance and internal structure possibly inheriting the morphology of microbial cells, were indirectly generated by some microenvironmental changes due to microbial activity; （3） the morphological features, size, occurrences and preservation of filamentous and rhabditiform microbodies indicate that they may be biogenic structures, and possibly mineralized microbial fossils; and （4） some kind of symbiotic relationship exists between microbial action and the Zoophycos

关键词： Geomicrobiology Carbonate microbodies Taiyuan Formation Trace fossil Zoophycos North China