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Maximal Integral over Observable Measures

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Acta Mathematica Sinica,English Series 2016年第5期32卷 571-578页

作者： yun zhao Department of Mathematics Soochow University

Let f be a continuous transformation on a compact, finite-dimensional manifold M, and φ a continuous function on M. This paper establishes the following formula：ess sup lim sup n→∞1/nφn（x）=sup{∫φdμ｜μ∈Of}≤lim sup n→∞1/n ess supφn（x）,where ess sup denotes the essential supremum taken against the Lebesgue measure,φn（x）=∑i=0^n-1φ（f^ix）and Of is the set of observable measures. Examples are provided to illustrate that the inequality could be an equality or strict. Moreover, if μ is the unique maximizing observable measure for φ, it is weakly statistical stable.

关键词： Observable measure ergodic averages statistical stable

Hedgehog in the Drosophila testis niche:what does it do there?

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Protein & Cell 2013年第9期4卷 650-655页

作者： zhao Zhan Chenyu Pan yun zhao State Key Laboratory of Cell Biology Institute of Biochemistry and Cell BiologyShanghai Institutes for Biological SciencesChinese Academy of SciencesShanghai 200031China

Stem cell niche is a specialized microenvironment crucial to *** testis in Drosophila contains two dif-ferent types of stem cells,the germline stem cells and the somatic cyst stem cells that are sustained by their respec-tive niche signals,thus is a good system for studying the interaction between the stem cells and their hosting *** JAK-STAT and BMP pathways are known to play critical roles in the self-renewal of different kinds of stem cells,but the roles of several other pathways have emerged recently in a complex signaling network in the testis *** of independent observations from three research groups have uncovered an important role of Hedgehog(Hh)in the Drosophila testis *** this review,we summarize these recent fi ndings and discuss the interplay between the Hh signaling mechanisms and those of the JAK-STAT and BMP *** also dis-cuss directions for further investigation.

关键词： Drosophila testis stem cell Hedgehog JAK-STAT

Variational principle and zero temperature limits of asymptotically （sub）-additive projection pressure

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Frontiers of Mathematics in China 2018年第5期13卷 1099-1120页

作者： Qiuhong WANG yun zhao School of Mathematical Sciences Soochow University Suzhou 215006 China

Let {Si}li=l be an iterated function system （IFS） on Rd with an attractor K. Let （S,cr） denote the one-sided full shift over the finite alphabet {1,2,...,l}, and let π：∑ -K be the coding map. Given an asymptotically （sub）-additive sequence of continuous functions{Si}n≥1, we define the asymptotically additive projection pressure Pπ and show the variational principle for Pπunder certain affine IFS. We also obtain variational principle for the asymptotically sub-additive projection pressure if the IFS satisfies asymptotically weak separation condition （AWSC）. Furthermore, when the IFS satisfies AWSC, we investigate the zero temperature limits of the asymptotically sub-additive projection pressure Pπ（β） with positive parameter β.

关键词： Projection pressure asymptotically (sub)-additive potentials variational principle zero temperature limits

NUMERICAL TECHNIQUE FOR TURBULENT TIDAL FLOW FIELD WITH ICE COVERS

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Journal of Hydrodynamics 1998年第1期10卷 94-101页

作者： Zeng, Ping zhao, yun China Inst of Water Resources & Hydropower Research Beijing China

Numerical modelling technique for ice flowing and melting field in coastal tidal currents for cooling water engineering design and research was presented based on k-Ε turbulence mathematical model and discretized moving-boundary-fitting coordinate system. To treat the complicated geometric, topographic and hydraulic conditions in a natural estuarine water were given. Numerical results show that model is practical and efficient to cooling water engineering research. An engineering application has been conducted by using the prediction on ice reduction and melting process by heated water discharges.

关键词： Computer simulation Flow of water Ice problems Numerical methods Tides Turbulent flow

Navigation message designing with high accuracy for NAV

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Chinese Journal of Aeronautics 2014年第4期27卷 994-1001页

作者： Wang Luxiao Huang Zhigang zhao yun School of Electronic and Information Engineering Beihang University

Navigation message designing with high accuracy guarantee is the key to efficient navigation message distribution in the global navigation satellite system（GNSS）. Developing high accuracy-aware navigation message designing algorithms is an important topic. This paper investigates the high-accuracy navigation message designing problem with the message structure *** contributions made in this paper include a heuristic that employs the concept of the estimated range deviation（ERD） to improve the existing well-known navigation message on L1 frequency（NAV） of global positioning system（GPS） for good accuracy service; a numerical analysis approximation method（NAAM） to evaluate the range error due to truncation（RET） of different navigation messages; and a basic positioning parameters designing algorithm in the limited space allocation. Based on the predicted ultra-rapid data from the ultra-rapid data from the international GPS service for geodynamic（IGU）, ERDs are generated in real time for error *** show that the algorithms developed in this paper are general and flexible, and thus are applicable to NAV improvement and other navigation message designs.

关键词： Error correction Estimated range deviation Navigation Orbit Range error due to truncation

Receiver-channel based adaptive blind equalization approach for GPS dynamic multipath mitigation

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Chinese Journal of Aeronautics 2013年第2期26卷 378-384页

作者： zhao yun Xue Xiaonan Zhang Tingfei School of Electronics and Information Engineering Beihang University

Aiming at mitigating multipath effect in dynamic global positioning system （GPS） satellite navigation applications, an approach based on channel blind equalization and real-time recursive least square （RLS） algorithm is proposed, which is an application of the wireless communication channel equalization theory to GPS receiver tracking loops. The blind equalization mechanism builds upon the detection of the correlation distortion due to multipath channels; therefore an increase in the number of correlator channels is required compared with conventional GPS receivers. An adaptive estimator based on the real-time RLS algorithm is designed for dynamic estimation of multipath channel response. Then, the code and carrier phase receiver tracking errors are compensated by removing the estimated multipath components from the correlators＇ outputs. To demonstrate the capabilities of the proposed approach, this technique is integrated into a GPS software receiver connected to a navigation satellite signal simulator, thus simulations under controlled dynamic multipath scenarios can be carried out. Simulation results show that in a dynamic and fairly severe multipath environment, the proposed approach achieves simultaneously instantaneous accurate multipath channel estimation and significant multipath tracking errors reduction in both code delay and carrier phase.

关键词： Blind equalization Correlation distortion Dynamic multipath mitigation Real-time recursive least square algorithm Satellite navigation

Properties and Applications of the Eccentric-gear Drive

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Chinese Journal of Mechanical Engineering 2011年第2期24卷 323-331页

作者： zhao yun SUN Liang YU Gaohong College of Mechanical Engineering and Automation Zhejiang Sci-Tech UniversiO Hangzhou 310018 China

The eccentric-gear can be used for variable speed ***,due to the vibrations caused by variation of backlash in working process,the eccentric-gear is seldom applied in engineering *** is just a little study about the *** it is necessary to take a further research on eccentric-gear transmission for the applications in the transplanting mechanism of high-speed rice *** key of this paper is to extend understanding of three following characteristics of this drive：（1） The rotation-center-distance and the geometrical-center-distance of the two meshing eccentric gears are respectively the hypotenuse and the straight edge of a right triangle in a cycle.（2） The geometrical center line of two meshing gears divides the linking-line of the two rotational centers equally.（3） When two times the eccentricity of gear,the rotation-center-distance and the geometrical-center-distance form a right triangle,the optimal value of rotation-center-distance can be *** addition,the kinematic analysis,such as the relationship between contact point and midpoint of the linking-line of two gears＇ rotational centers,transmission ratio between the driving-gear and the driven-gear,contact angle and coordinate of contact point are be made,further the formula for calculation of contact force,flow chart for writing optimization program and curve for analysis of data are also be *** relationship between the rotation-center-distance and the geometrical-center-distance,which is determined by three characteristics mentioned above, is a key for the rational design and application of eccentric-gear ***,the presented right triangle property of eccentric gear drive is an important reference for effective analysis of dynamic characteristic of eccentric-gear mechanism and its reliable design.

关键词： eccentric gear transmission property variable speed transmission kinematic and dynamic analysis

Preparation of Ferrioxalate Submicrorods/Graphene Composites and Their Photocatalytic Properties

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Journal of Materials Science & Technology 2014年第2期30卷 117-122页

作者： Min Fu yun zhao Qingze Jiao School of Chemical Engineering and the Environment Beijing Institute of Technology

Ferrioxalate submicrorods/graphene composites were synthesized through a simple solvothermal process in a mixture of ethylene glycol and water. The in situ growth of ferrioxalate submicrorods and the reduction of graphene oxide （GO） were completed in a one-step reaction. Fourier transform infrared and Raman spectroscopy confirmed the reduction of GO. Uniform rod-like ferrioxalates with diameter of about 600 nm and length of several micrometers were well distributed on the graphene sheets. As-obtained composites exhibited better photocatalytic properties than pure ferrioxalate submicrorods. The influence of different contents of GO on photocatalytic performance was also investigated. A possible photocatalytic mechanism of ferrioxalate submicrorods/graphene composites was proposed.

关键词： Ferrioxalate submicrorods Graphene Photocatalysis

Call for knowledge systematization:An example from lithium ion batteries recycling

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Journal of Energy Chemistry 2024年第7期94卷 169-170页

作者： yun zhao Baohua Li Institute of Materials Research Tsinghua Shenzhen International Graduate SchoolTsinghua UniversityShenzhen 518055GuangdongChina

Scientific research is one of the primary ways to drive human civilization *** research institutions and researchers worldwide are dedicated to exploring the unknown,resulting in a flood of research findings[1].For instance,Web of Science alone collects over 10,000 academic papers on a daily *** each research field typically has around 10%of review articles,these mainly focus on a limited portion of the subject,failing to provide a comprehensive and real-time updated *** a result,researchers or students in a particular field may spend several months,or even longer,comprehending the state of research that has developed over just a few *** lack of systematic background often leads to redundant or similar studies,which is highly detrimental to the progress of science and technology.

关键词： lithium typically spend