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Ocean ecosystem discrete time dynamics generated by l-Vol terra operators
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作者 U.A.Rozikov S.K.Shoyimardonov 《生物数学学报:英文版》 2019年第2期77-100,共24页
We consider a discrete-time dynamical system generated by a nonlinear operator(with four real parameters a,b,c,d)of ocean ecosystem.We find conditions on the parameters under which the operator is reduced to a l-Volte... We consider a discrete-time dynamical system generated by a nonlinear operator(with four real parameters a,b,c,d)of ocean ecosystem.We find conditions on the parameters under which the operator is reduced to a l-Volterra quadratic stochastic operator mapping two-dimensional simplex to itself.We show that if cd(c+d)=0,then(under some conditions on a,b)this l-Volterra operator may have up to three or a countable set of fixed points;if cd(c+d)≠0,then the operator has up to three fixed points.Depending on the parameters,the fixed points may be attracting,repelling or saddle points.The limit behaviors of trajectories of the dynamical system are studied.It is shown that independently on values of parameters and on initial(starting)point,all trajectories converge.Thus,the operator(dynamical system)is regular.We give some biological interpretations of our results. 展开更多
关键词 QUADRATIC stochastic OPERATOR VOLTERRA OPERATOR l-Volterra OPERATOR ECOSYSTEM modeling
排序语义与“能”和“可以”的语义和句法分析
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作者 王莹莹 潘海华 《当代语言学》 CSSCI 北大核心 2019年第3期385-399,共15页
本文首先采用情态的经典排序语义(ordering semantics)解释方法(Kratzer 1981, 1991)分析了“能”和“可以”在不同语境下产生不同解读的来源和差别。然后,结合目前汉语情态词的句法研究,指出了“能”和“可以”的上述语义与其句法的不... 本文首先采用情态的经典排序语义(ordering semantics)解释方法(Kratzer 1981, 1991)分析了“能”和“可以”在不同语境下产生不同解读的来源和差别。然后,结合目前汉语情态词的句法研究,指出了“能”和“可以”的上述语义与其句法的不匹配问题,并通过区分S-算子和VP-算子的情态词来解决该问题。前者包括表达认知情态、应然性优先情态及纯环境情态的情态词;后者包括表达应为性优先情态和倾向情态的情态词。这一区分揭示了目前汉语情态词句法研究(如胡波 2015)中存在的一些问题,我们基于情态词的语义特性为其提出了修正意见。 展开更多
关键词 情态 排序语义 S-算子 VP-算子 提升与控制
Compactness for the commutators of multilinear singular integral operators with non-smooth kernels 预览
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作者 BU Rui CHEN Jie-cheng 《高校应用数学学报:英文版(B辑)》 SCIE CSCD 2019年第1期55-75,共21页
In this paper,the behavior for commutators of a class of bilinear singular integral operators associated with non-smooth kernels on the product of weighted Lebesgue spaces is considered.By some new maximal functions t... In this paper,the behavior for commutators of a class of bilinear singular integral operators associated with non-smooth kernels on the product of weighted Lebesgue spaces is considered.By some new maximal functions to control the commutators of bilinear singular integral operators and CMO(Rn)functions,compactness for the commutators is proved. 展开更多
关键词 singular integral OPERATOR maximal function weighted norm inequality COMMUTATOR compact OPERATOR
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Hermite-Hadamard Type Inequalities for Operator h-preinvex Functions 预览
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作者 Lian Tie-yan Tang Wei Ji You-qing 《数学研究通讯:英文版》 CSCD 2019年第2期180-192,共13页
Operator h-preinvex functions are introduced and a refinement of HermiteHadamard type inequalities for such functions is established. Results proved in this paper are more general and some known results are special ca... Operator h-preinvex functions are introduced and a refinement of HermiteHadamard type inequalities for such functions is established. Results proved in this paper are more general and some known results are special cases. 展开更多
关键词 Hermite-Hadamard's integral INEQUALITY OPERATOR h-preinvex FUNCTION OPERATOR beta-preinvex FUNCTION
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Bloch-type spaces and extended Cesàro operators in the unit ball of a complex Banach space
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作者 Hidetaka Hamada 《中国科学:数学英文版》 SCIE CSCD 2019年第4期617-628,共12页
Let B be the unit ball of a complex Banach space X. In this paper, we generalize the Bloch-type spaces and the little Bloch-type spaces to the open unit ball B by using the radial derivative. Next, we define an extend... Let B be the unit ball of a complex Banach space X. In this paper, we generalize the Bloch-type spaces and the little Bloch-type spaces to the open unit ball B by using the radial derivative. Next, we define an extended Cesaro operator Tφ with the holomorphic symbol φ and characterize those φ for which Tφ is bounded between the Bloch-type spaces and the little Bloch-type spaces. We also characterize those φ for which Tφ is compact between the Bloch-type spaces and the little Bloch-type spaces under some additional assumption on the symbol φ. When B is the open unit ball of a finite dimensional complex Banach space X, this additional assumption is automatically satisfied. 展开更多
关键词 Bloch-type SPACE COMPLEX Banach SPACE EXTENDED CESARO operator little Bloch-type SPACE
A Two-Level Additive Schwarz Preconditioner for Local C^0 Discontinuous Galerkin Methods of Kirchhoff Plates 预览
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作者 Jianguo Huang Xuehai Huang 《应用数学与计算数学学报(英文)》 2019年第2期167-185,共19页
A two-level additive Schwarz preconditioner based on the overlapping domain decomposition approach is proposed for the local C^0 discontinuous Galerkin (LCDG) method of Kirchhoff plates. Then with the help of an inter... A two-level additive Schwarz preconditioner based on the overlapping domain decomposition approach is proposed for the local C^0 discontinuous Galerkin (LCDG) method of Kirchhoff plates. Then with the help of an intergrid transfer operator and its error estimates,it is proved that the condition number is bounded by O(1 4-(H^4/δ^4)),where H is the diameter of the subdomains and 8 measures the overlap among subdomains. And for some special cases of small overlap,the estimate can be improved as O(1 +(H^3/δ^3)). At last,some numerical results are reported to demonstrate the high efficiency of the two-level additive Schwarz preconditioner. 展开更多
关键词 KIRCHHOFF plate C^0 DISCONTINUOUS GALERKIN TWO-LEVEL additive SCHWARZ PRECONDITIONER Intergrid transfer operator
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特种设备作业人员培训管理浅论 预览
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作者 朱海滨 《化工装备技术》 CAS 2019年第2期23-26,共4页
特种设备作业人员应具备一定的安全知识和必要的操作技能,这也是保障特种设备安全运行的重要条件。从多个角度分析论述了特种设备作业人员的培训管理工作,提出了业界应多方协作,共同努力做好培训管理工作。
关键词 特种设备 作业人员 培训考核 监管
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Convergence of neutral type proportional-delayed HCNNs with D operators
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作者 Yanli Xu Jiaming Zhong 《生物数学学报:英文版》 2019年第1期33-41,共9页
This paper is concerned with neutral type high-order cellular neural networks(HCNNs)involving proportional delays and D operators.Some criteria are established for the global exponential convergence of the addressed m... This paper is concerned with neutral type high-order cellular neural networks(HCNNs)involving proportional delays and D operators.Some criteria are established for the global exponential convergence of the addressed models by using differential inequality techniques.Moreover,an example and its numerical simulations are employed to illustrate the main results. 展开更多
关键词 EXPONENTIAL CONVERGENCE NEUTRAL type HIGH-ORDER cellular neural networks proportional delay D OPERATOR
Meromorphic Function Sharing Sets with Its Difference Operator or Shifts
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作者 Bingmao DENG Chunlin LEI Mingliang FANG 《数学年刊:B辑英文版》 SCIE CSCD 2019年第3期331-338,共8页
Let f be a nonconstant meromorphic function, c ∈ C, and let ■be a meromorphic function. If f(z) and P(z, f(z)) share the sets {a(z),-a(z)},{0} CM almost and share {∞} IM almost, where P(z, f(z)) is defined as(1.1),... Let f be a nonconstant meromorphic function, c ∈ C, and let ■be a meromorphic function. If f(z) and P(z, f(z)) share the sets {a(z),-a(z)},{0} CM almost and share {∞} IM almost, where P(z, f(z)) is defined as(1.1), then f(z) ≡±P(z, f(z)) or f(z)P(z, f(z)) ≡±a~2(z). This extends the results due to Chen and Chen(2013), Liu(2009) and Yi(1987). 展开更多
关键词 MEROMORPHIC function DIFFERENCE OPERATOR SHARED SETS
A survey of the Szeg? equation Dedicated to Professor Jean-Yves Chemin on the Occasion of His 60th Birthday
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作者 Patrick Gérard Sandrine Grellier 《中国科学:数学英文版》 SCIE CSCD 2019年第6期1087-1100,共14页
We survey the main properties of the cubic Szeg? equation from the PDE viewpoint, emphasising global existence of smooth solutions, analytic regularity, growth of high Sobolev norms and the effects of weak damping.
关键词 cubic Szeg? EQUATION INTEGRABLE system HANKEL operator spectral analysis ANALYTIC REGULARITY wave turbulence
Convergence of Solutions of General Dispersive Equations Along Curve
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作者 Yong DING Yaoming NIU 《数学年刊:B辑英文版》 SCIE CSCD 2019年第3期363-388,共26页
In this paper, the authors give the local L2 estimate of the maximal operator Sφ,γ* of the operator family {St,φ,γ} defined initially by ■which is the solution(when n = 1) of the following dispersive equations(*)... In this paper, the authors give the local L2 estimate of the maximal operator Sφ,γ* of the operator family {St,φ,γ} defined initially by ■which is the solution(when n = 1) of the following dispersive equations(*) along a curve γ:■where φ : R+→R satisfies some suitable conditions and φ((-?)1/2) is a pseudo-differential operator with symbol φ(|ξ|). As a consequence of the above result, the authors give the pointwise convergence of the solution(when n = 1) of the equation(*) along curve γ.Moreover, a global L2 estimate of the maximal operator Sφ,γ* is also given in this paper. 展开更多
关键词 L~2 ESTIMATE Global MAXIMAL OPERATOR DISPERSIVE equation CURVE
Plug-and-Play Based Optimization Algorithm for New Crime Density Estimation
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作者 Xiang-Chu Feng Chen-Ping Zhao +2 位作者 Si-Long Peng Xi-Yuan Hu Zhao-Wei Ouyang 《计算机科学技术学报:英文版》 SCIE EI CSCD 2019年第2期476-493,共18页
Different from a general density estimation,the crime density estimation usually has one important factor:the geographical constraint.In this paper,a new crime density estimation model is formulated,in which the regio... Different from a general density estimation,the crime density estimation usually has one important factor:the geographical constraint.In this paper,a new crime density estimation model is formulated,in which the regions where crime is impossible to happen,such as mountains and lakes,are excluded.To further optimize the estimation method,a learning-based algorithm,named Plug-and-Play,is implanted into the augmented Lagrangian scheme,which involves an off-the-shelf filtering operator.Different selections of the filtering operator make the algorithm correspond to several classical estimation models.Therefore,the proposed Plug-and-Play optimization based estimation algorithm can be regarded as the extended version and general form of several classical methods.In the experiment part,synthetic examples with different invalid regions and samples of various distributions are first tested.Then under complex geographic constraints,we apply the proposed method with a real crime dataset to recover the density estimation.The state-of-the-art results show the feasibility of the proposed model. 展开更多
关键词 CRIME density estimation AUGMENTED LAGRANGIAN strategy Plug-and-Play filtering operator
Behaviour of the Stokes operators under domain perturbation Dedicated to Professor Jean-Yves Chemin on the Occasion of His 60th Birthday
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作者 Sylvie Monniaux 《中国科学:数学英文版》 SCIE CSCD 2019年第6期1167-1174,共8页
Depending on the geometry of the domain, one can define—at least—three different Stokes operators with Dirichlet boundary conditions. We describe how the resolvents of these Stokes operators converge with respect to... Depending on the geometry of the domain, one can define—at least—three different Stokes operators with Dirichlet boundary conditions. We describe how the resolvents of these Stokes operators converge with respect to a converging sequence of domains. 展开更多
关键词 domain PERTURBATION STOKES operator DIRICHLET boundary conditions
基于STM32的手势识别控制器的设计 预览
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作者 牛作东 李捍东 《电子测试》 2019年第6期20-21,17共3页
随着工业技术的发展,对于仪器仪表的操作方式要求也不断更新,针对传统的操作方式,人机接触容易产生静电,设备易损,安全性低等缺点以及对于非接触式操作要求的应用场合越来越多,本文基于ARM处理器和光学传感器设计了一款非接触式的手势... 随着工业技术的发展,对于仪器仪表的操作方式要求也不断更新,针对传统的操作方式,人机接触容易产生静电,设备易损,安全性低等缺点以及对于非接触式操作要求的应用场合越来越多,本文基于ARM处理器和光学传感器设计了一款非接触式的手势识别操作控制器,通过识别手势动作对仪器仪表设备进行操作。通过应用表明该设计操作简便,体积小,安全性高,可应用场景广泛。 展开更多
关键词 手势识别 传感器 STM32 操作器
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Discrete Fractional Lagrange Equations of Nonconservative Systems 预览
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作者 SONG Chuanjing ZHANG Yi 《南京航空航天大学学报:英文版》 EI CSCD 2019年第1期175-180,共6页
In order to study discrete nonconservative system,Hamilton’s principle within fractional difference operators of Riemann-Liouville type is given. Discrete Lagrange equations of the nonconservative system as well as t... In order to study discrete nonconservative system,Hamilton’s principle within fractional difference operators of Riemann-Liouville type is given. Discrete Lagrange equations of the nonconservative system as well as the nonconservative system with dynamic constraint are established within fractional difference operators of Riemann- Liouville type from the view of time scales. Firstly,time scale calculus and fractional calculus are reviewed. Secondly,with the help of the properties of time scale calculus,discrete Lagrange equation of the nonconservative system within fractional difference operators of Riemann-Liouville type is presented. Thirdly,using the Lagrange multipliers,discrete Lagrange equation of the nonconservative system with dynamic constraint is also established. Then two special cases are discussed. Finally,two examples are devoted to illustrate the results. 展开更多
关键词 DISCRETE LAGRANGE equation time scale FRACTIONAL DIFFERENCE OPERATOR NONCONSERVATIVE system
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Lower Bounds of Dirichlet Eigenvalues for General Grushin Type Bi-Subelliptic Operators 预览
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作者 Hua Chen Hongge Chen +1 位作者 Junfang Wang Nana Zhang 《分析理论与应用:英文刊》 CSCD 2019年第1期66-84,共19页
Let Q be a bounded open domain in R^n with smooth boundaryаΩ.Let X=(X1,X2…,Xm)be a system of general Grushin type vector fields defined onΩand the boundaryаΩis non-characteristic for X.For△x=∑j=1^mXj^2,we den... Let Q be a bounded open domain in R^n with smooth boundaryаΩ.Let X=(X1,X2…,Xm)be a system of general Grushin type vector fields defined onΩand the boundaryаΩis non-characteristic for X.For△x=∑j=1^mXj^2,we denoteλk as the k-th eigenvalue for the bi-subelliptic operator△X2^2 onΩ.In this paper,by using the sharp sub-elliptic estimates and maximally hypoeliptic estimates,we give the optimal lower bound estimates ofλk for the operatork△X^2. 展开更多
关键词 EIGENVALUES degenerate ELLIPTIC operators sub-elliptic ESTIMATE MAXIMALLY hypoelliptic ESTIMATE bi-subelliptic operator
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运营商统一DPI系统的建设 预览
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作者 丁凡 《通信电源技术》 2019年第6期261-262,共2页
运营商自身流量的自我感知分析、市场精准营销及信息安全监控等都依托于DPI系统对数据的深度挖掘和分析。因此,阐述了传统DPI系统存在的问题,简要分析了统一DPI系统的建设思路及部署方案。
关键词 运营商 统一DPI系统 部署方案
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A degenerate elliptic system with variable exponents
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作者 Lingju Kong 《中国科学:数学英文版》 SCIE CSCD 2019年第7期1373-1390,共18页
We study a degenerate elliptic system with variable exponents. Using the variational approach and some recent theory on weighted Lebesgue and Sobolev spaces with variable exponents, we prove the existence of at least ... We study a degenerate elliptic system with variable exponents. Using the variational approach and some recent theory on weighted Lebesgue and Sobolev spaces with variable exponents, we prove the existence of at least two distinct nontrivial weak solutions of the system. Several consequences of the main theorem are derived;in particular, the existence of at lease two distinct nontrivial non-negative solutions is established for a scalar degenerate problem. One example is provided to show the applicability of our results. 展开更多
关键词 DEGENERATE ELLIPTIC systems DEGENERATE p(x)-Laplacian operator weak solutions weighted variable EXPONENT spaces mountain pass LEMMA
Current Status and Future Challenges of Weather Radar Polarimetry: Bridging the Gap between Radar Meteorology/Hydrology/Engineering and Numerical Weather Prediction 预览
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作者 Guifu ZHANG Vivek N.MAHALE +25 位作者 Bryan J.PUTNAM Youcun QI Qing CAO Andrew D. BYRD Petar BUKOVCIC Dusan S.ZRNIC Jidong GAO Ming XUE Youngsun JUNG Heather D.REEVES Pamela L.HEINSELMAN Alexander RYZHKOV Robert D. PALMER Pengfei ZHANG Mark WEBER Greg M.MCFARQUHAR Berrien MOORE III Yan ZHANG Jian ZHANG J.VIVEKANANDAN Yasser AL-RASHID Richard L.ICE Daniel S.BERKOWITZ Chong-chi TONG Caleb FULTON Richard J. DOVIAK 《大气科学进展:英文版》 SCIE CAS CSCD 2019年第6期571-588,共18页
After decades of research and development, the WSR-88 D(NEXRAD) network in the United States was upgraded with dual-polarization capability, providing polarimetric radar data(PRD) that have the potential to improve we... After decades of research and development, the WSR-88 D(NEXRAD) network in the United States was upgraded with dual-polarization capability, providing polarimetric radar data(PRD) that have the potential to improve weather observations,quantification, forecasting, and warnings. The weather radar networks in China and other countries are also being upgraded with dual-polarization capability. Now, with radar polarimetry technology having matured, and PRD available both nationally and globally, it is important to understand the current status and future challenges and opportunities. The potential impact of PRD has been limited by their oftentimes subjective and empirical use. More importantly, the community has not begun to regularly derive from PRD the state parameters, such as water mixing ratios and number concentrations, used in numerical weather prediction(NWP) models.In this review, we summarize the current status of weather radar polarimetry, discuss the issues and limitations of PRD usage, and explore potential approaches to more efficiently use PRD for quantitative precipitation estimation and forecasting based on statistical retrieval with physical constraints where prior information is used and observation error is included. This approach aligns the observation-based retrievals favored by the radar meteorology community with the model-based analysis of the NWP community. We also examine the challenges and opportunities of polarimetric phased array radar research and development for future weather observation. 展开更多
关键词 WEATHER RADAR POLARIMETRY RADAR METEOROLOGY numerical WEATHER prediction data assimilation MICROPHYSICS parameterization forward operator
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我国核损害赔偿责任制度缺陷及立法建构 预览
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作者 陈建 《大连理工大学学报:社会科学版》 CSSCI 北大核心 2019年第3期62-68,共7页
核风险的不确定性揭示了我国核损害赔偿责任制度的缺陷,存在立法阙如、单一性司法救济、重事后赔偿、赔偿限额低且缺乏动态性、风险分担机制狭窄、诉讼时效短等问题。有关核损害赔偿的国际公约和主要有核国家的立法规范与赔偿实践值得... 核风险的不确定性揭示了我国核损害赔偿责任制度的缺陷,存在立法阙如、单一性司法救济、重事后赔偿、赔偿限额低且缺乏动态性、风险分担机制狭窄、诉讼时效短等问题。有关核损害赔偿的国际公约和主要有核国家的立法规范与赔偿实践值得我国借鉴。结合我国国情,针对立法建构问题提出以下建议:核损害赔偿责任制度以分散至《核安全法》中为宜;建立效率优先、兼顾公平的损害赔偿模式;实行动态化的限额标准管理,适时提高责任限额;建立横向多元、纵向多级的财务保证制度;建立核损害赔偿应急制度;延长诉讼时效。 展开更多
关键词 核损害 赔偿责任 风险社会 营运人
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