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冷水水表多表式检定方法 被引量:3
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作者 费平 陈岚 朱海东 《上海计量测试》 2017年第1期30-33,共4页
针对目前冷水水表检定装置检定效率较低的现状,对20表位启停容积法摄像头自动读数冷水水表检定装置进行了实验研究和改进设计,重点分析了水压、流量对检定结果的影响。对冷水水表示值误差的测量结果进行了不确定度评定,并采用比对法对... 针对目前冷水水表检定装置检定效率较低的现状,对20表位启停容积法摄像头自动读数冷水水表检定装置进行了实验研究和改进设计,重点分析了水压、流量对检定结果的影响。对冷水水表示值误差的测量结果进行了不确定度评定,并采用比对法对评定结果进行了验证。实验结果表明,改进设计后的20表位启停容积法冷水水表检定装置是可行的,其在满足JJG 162-2009《冷水水表》要求的前提下可以提高检定效率。 展开更多
关键词 冷水水 多表式 示值误差 检定方法
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多用户组合式全电子新型单相电能表 被引量:2
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作者 富致超 费宇航 +3 位作者 高作石 耿心志 张旭辉 张红阳 《电测与仪表》 北大核心 1995年第12期3-5,共3页
本文论述了多用户组合式电子电能表的必要性、可能性。介绍了其方案、功能特点、工作原理及有关设计问题。这种表特别适合于民用住宅楼中计费用(外形见本期封底照片)。
关键词 多表位组合 电能 自动抄 用电管理
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Solving Dirac Equation with New Ring-Shaped Non-Spherical Harmonic Oscillator Potential 被引量:2
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作者 胡先权 罗光 +2 位作者 毋志民 牛连斌 马燕 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第2期242-246,共5页
A new ring-shaped non-harmonic oscillator potential is proposed. The precise bound solution of Dirac equation with the potential is gained when the scalar potential is equal to the vector potential. The angular equati... A new ring-shaped non-harmonic oscillator potential is proposed. The precise bound solution of Dirac equation with the potential is gained when the scalar potential is equal to the vector potential. The angular equation and radial equation are obtained through the variable separation method. The results indicate that the normalized angle wave function can be expressed with the generalized associated-Legendre polynomial, and the normalized radial wave function can be expressed with confluent hypergeometric function. And then the precise energy spectrum equations are obtained. The ground state and several low excited states of the system are solved. And those results are compared with the non-relativistic effect energy level in Phys. Lett. A 340 (2005) 94. The positive energy states of system are discussed and the conclusions are made properly. 展开更多
关键词 ring-shaped non-harmonic oscillator potential Dirac equation bound state generalizedassoeiated-Legendre function
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Generalized Bargmann Representation of Spin Coherent State 被引量:1
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作者 FANHong-Yi CHENJun-Hu 《Communications in Theoretical Physics》 SCIE CAS CSCD 2004年第4期537-540,共4页
Based on the conclusion that the generalized Bargmann representation of a two-mode Fock state is a two-variable Hermite polynomial function /Hong-Yi Fan and Jun-hua Chen,Phys.Lett.A303(2002)311] we derive the generali... Based on the conclusion that the generalized Bargmann representation of a two-mode Fock state is a two-variable Hermite polynomial function /Hong-Yi Fan and Jun-hua Chen,Phys.Lett.A303(2002)311] we derive the generalized Bargmann representation of the spin coherent state and some new relations in the generalized function space. 展开更多
关键词 spin coherent state generalized Bargmann representation Hermite polynomials
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Construction of Odd-Variable Boolean Function with Maximum Algebraic Immunity Using Univariate Polynomial Representation
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作者 Zhao Wentao Fu Shaojing +1 位作者 Li Chao Qu Longjiang 《China Communications》 SCIE CSCD 2012年第10期33-39,共7页
To protect against algebraic attacks, a high algebraic immunity is now an important criterion for Boolean functions used in stream ciphers. In this paper, a new method based on a univariate polynomial representation o... To protect against algebraic attacks, a high algebraic immunity is now an important criterion for Boolean functions used in stream ciphers. In this paper, a new method based on a univariate polynomial representation of Boolean functions is proposed. The proposed method is used to constmct Boolean functions with an odd number of variables and with maximum algebraic immunity. We also discuss the nonlinearity of the constructed functions. Moreover, a lower bound is deter- mined for the number of Boolean functions with rmximum algebraic immunity. 展开更多
关键词 CRYPTOGRAPHY boolean function alge- braic attack algebraic immunity
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Impact of global sea surface temperature on the recent early winter Arctic tropospheric warming in coordinated large ensemble simulations
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作者 Lutao Wang Yongqi Gao +3 位作者 Dong Guo Tao Wang Ying Zhang Wei Hua 《Atmospheric and Oceanic Science Letters》 CSCD 2021年第1期57-62,共6页
Coordinated numerical ensemble experiments with six different state-of-the-art atmosphere models were used to evaluate and quantify the impact of global SST(from reanalysis data)on the early winter Arctic warming duri... Coordinated numerical ensemble experiments with six different state-of-the-art atmosphere models were used to evaluate and quantify the impact of global SST(from reanalysis data)on the early winter Arctic warming during 1982-2014.Two sets of experiments were designed:in the first set(EXP1),OISSTv2 daily sea-ice concentration and SST variations were used as the lower boundary forcing,while in the second set(EXP2)the SST data were replaced by the daily SST climatology.In the results,the multi-model ensemble mean of EXP1 showed a nearsurface(~850 hPa)warming trend of 0.4℃/10 yr,which was 80%of the warming trend in the reanalysis.The simulated warming trend was robust across the six models,with a magnitude of 0.36-0.50℃/10 yr.The global SST could explain most of the simulated warming trend in EXP1 in the mid and low troposphere over the Arctic,and accounted for 58%of the simulated near-surface warming.The results also suggest that the uppertropospheric warming(~200 hPa)over the Arctic in the reanalysis is likely not a forced signal;rather,it is caused by natural climate variability.The source regions that can potentially impact the early winter Arctic warming are explored and the limitations of the study are discussed. 展开更多
关键词 Arctic warming Sea surface temperature Multi-model coordinated experiment Eliassen-Palm flux Planetary wave
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A Note on Special Functions Related to Lotka / Negative Volterra Equations
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作者 Takashi Fujiwara 《Journal of Mathematics and System Science》 2017年第7期186-197,共12页
We study special functions related to Lotka-Volterra equations and negative Volterra equation intro-duced from zero curvature representations . At first we show the relationships between Lotka-Volterra equations intro... We study special functions related to Lotka-Volterra equations and negative Volterra equation intro-duced from zero curvature representations . At first we show the relationships between Lotka-Volterra equations introduced from zero curvature representations and symmetric orthogonal polynomials. Sec-ondarily, we describe the relationships between negative Volterra equations with a special solutions and cylinder functions. 展开更多
关键词 Lotka-Volterra equations Negative Volterra equations symmetric orthogonal polynomials cylinder functions three term recurrences
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Wave Extraction with Portable High-Frequency Surface Wave Radar OSMAR-S 被引量:2
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作者 ZHOU Hao ROARTY Hugh WEN Biyang 《Journal of Ocean University of China》 SCIE CAS 2014年第6期957-963,共7页
High frequency surface wave radar(HFSWR) has now gained more and more attention in real-time monitoring of sea surface states such as current, waves and wind. Normally a small-aperture antenna array is preferred to a ... High frequency surface wave radar(HFSWR) has now gained more and more attention in real-time monitoring of sea surface states such as current, waves and wind. Normally a small-aperture antenna array is preferred to a large-aperture one due to the easiness and low cost to set up. However, the large beam-width and the corresponding incorrect division of the first- and second-order Doppler spectral regions often lead to big errors in wave height and period estimations. Therefore, for the HFSWR with a compact cross-loop/monopole antenna(CMA), a new algorithm involving improved beam-forming(BF) and spectral division techniques is proposed. On one hand, the cross-spectrum of the output sequence by the conventional beam-forming(CBF) with all the three elements and the output with only the two loops is used in place of the CMA output self-spectrum to achieve a decreased beam-width; on the other hand, the better null seeking process is included to improve the division accuracy of the first- and second-order regions. The algorithm is used to reprocess the data collected by the portable HFSWR OSMAR-S during the Sailing Competition of the 16 th Asian Games held in Shanwei in November 2010, and the improvements of both the correlation coefficients and root-mean-square(RMS) errors between the wave height and period estimations and in situ buoy measurements are obvious. The algorithm has greatly enhanced the capabilities of OSMAR-S in wave measurements. 展开更多
关键词 HFSWR wave height wave period in situ comparison beam-forming cross-loop
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Entanglement Involved in Pair Coherent State Studied via Wigner Function Formalism
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作者 HU Li-Yun FAN Hong-Yi 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第12期1071-1075,共5页
We calculate Wigner function, tomogram of the pair coherent state by using its Sehmidt decomposition in the coherent state representation. It turns out that the Wigner function can be seen as the quantum entanglement ... We calculate Wigner function, tomogram of the pair coherent state by using its Sehmidt decomposition in the coherent state representation. It turns out that the Wigner function can be seen as the quantum entanglement (QE) between two two-variable Hermite polynomials (TVHP) and the tomogram is further simplified as QE of two single-variable Hermite polynomials. The Husimi function of pair coherent state is also calculated. 展开更多
关键词 pair coherent state Wigner function TOMOGRAM Husimi function
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Motion Estimation of an Omnidirectional Mobile Robot
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作者 Mkhinini Maher Knani Jilani 《Journal of Mechanics Engineering and Automation》 2011年第5期357-364,共8页
The motion's generation consists in finding an analytic expression of a motion according to time. A Map road type planner or Cell decomposition provide to the motion generator some possible free crossing points of co... The motion's generation consists in finding an analytic expression of a motion according to time. A Map road type planner or Cell decomposition provide to the motion generator some possible free crossing points of collision. The global trajectory's interpolation by a polynomial is generally not possible, because the degree of the polynomial increases with the number of crossing points which can generate vibrations or loops of the. trajectory. The solution consists in using polynomials in an inferior degree and to build the motion in pieces. The theoretical developments concern the motion's generation, the modeling of the vehicle, then the management of its redundancy steam-power. All these methods contribute to improve the robot precision (accuracy). The authors are presenting the motion's generator which constructs into lines a continuous trajectory C2 while enabling the transformation of the crossing points into lines. The generator presented here as part of omnidirectional robot is adaptable to any kind of vehicle. 展开更多
关键词 ROBOTICS generation control MOTION omnidirectionnal mobile robot.
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Computing polynomial univariate representations of zero-dimensional ideals by Grbner basis 被引量:3
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作者 MA XiaoDong SUN Yao WANG DingKang 《Science China Mathematics》 SCIE 2012年第6期1293-1302,共10页
Rational Univariate Representation (RUR) of zero-dimensional ideals is used to describe the zeros of zero-dimensional ideals and RUR has been studied extensively. In 1999, Roullier proposed an efficient algorithm to... Rational Univariate Representation (RUR) of zero-dimensional ideals is used to describe the zeros of zero-dimensional ideals and RUR has been studied extensively. In 1999, Roullier proposed an efficient algorithm to compute RUR of zero-dimensional ideals. In this paper, we will present a new algorithm to compute Polynomial Univariate Representation (PUR) of zero-dimensional ideals. The new algorithm is based on some interesting properties of Grobner basis. The new algorithm also provides a method for testing separating elements. 展开更多
关键词 RUR PUR zero-dimensional ideals Grobner basis
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Coherent state and normal ordering method for transiting Hermite polynomials to Laguerre polynomials 被引量:3
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作者 FAN HongYi ZHOU Jun 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2012年第4期605-608,共4页
By virtue of the coherent state representation and the operator ordering method we find a new approach for transiting Hermite polynomials to Laguerre polynomials. We also derive the new reciprocal relation of Laguerre... By virtue of the coherent state representation and the operator ordering method we find a new approach for transiting Hermite polynomials to Laguerre polynomials. We also derive the new reciprocal relation of Laguerre polynomials ∑n=0 (-1)n (n^l)Ln (x) = x^l/n, n-O and its application in deriving the sum rule of the Wingner function of Fock states is demonstrated. Some new expansion identities about the operator Laguerre polynomial are also derived. This opens a new route of deriving mathematical polynomials formulas by virtute of the quantum mechanical representations and operator ordering technique. 展开更多
关键词 coherent state Hermite polynomial Laguerre polynomial normal ordering
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Dependence of femtosecond time-resolved magneto-optical Kerr rotation on the direction of polarization of the probe beam 被引量:1
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作者 FENG XiaoBo LI Yan +3 位作者 QIN Yi XIAO YunFeng YANG Hong GONG QiHuang 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2011年第8期1411-1415,共5页
We demonstrate that the femtosecond time-resolved magneto-optical Kerr rotation oscillates with the direction of polarization of the probe beam when a sample of Al0.25Ga0.75As/GaAs multi-quantum wells is excited by a ... We demonstrate that the femtosecond time-resolved magneto-optical Kerr rotation oscillates with the direction of polarization of the probe beam when a sample of Al0.25Ga0.75As/GaAs multi-quantum wells is excited by a circularly polarized pump and detected by a linearly polarized probe at wavelengths from 800 to 830 nm. Analytical expressions are derived to explain the mechanism, which is in good agreement with the numerical computation and the experimental data. The results suggest that the Kerr signal can be enhanced by choosing an optimal direction of polarization, which is of benefit to the measurement of the weak Kerr rotation. 展开更多
关键词 time-resolved Kerr rotation spin dynamics direction of polarization
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A sixth-order wavelet integral collocation method for solving nonlinear boundary value problems in three dimensions 被引量:1
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作者 Zhichun Hou Jiong Weng +2 位作者 Xiaojing Liu Youhe Zhou Jizeng Wang 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2022年第2期81-92,I0003,共13页
A sixth-order accurate wavelet integral collocation method is proposed for solving high-order nonlinear boundary value problems in three dimensions.In order to realize the establishment of this method,an approximate e... A sixth-order accurate wavelet integral collocation method is proposed for solving high-order nonlinear boundary value problems in three dimensions.In order to realize the establishment of this method,an approximate expression of multiple integrals of a continuous function defined in a three-dimensional bounded domain is proposed by combining wavelet expansion and Lagrange boundary extension.Through applying such an integral technique,during the solution of nonlinear partial differential equations,the unknown function and its lower-order partial derivatives can be approximately expressed by its highest-order partial derivative values at nodes.A set of nonlinear algebraic equations with respect to these nodal values of the highest-order partial derivative is obtained using a collocation method.The validation and convergence of the proposed method are examined through several benchmark problems,including the eighth-order two-dimensional and fourth-order three-dimensional boundary value problems and the large deflection bending of von Karman plates.Results demonstrate that the present method has higher accuracy and convergence rate than most existing numerical methods.Most importantly,the convergence rate of the proposed method seems to be independent of the order of the differential equations,because it is always sixth order for second-,fourth-,sixth-,and even eighth-order problems. 展开更多
关键词 Nonlinear boundary value problems Eighth-order derivative Coiflet wavelet Integral collocation method Von Karman plate
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Effect of polypeptide 2B1 on condition of dampness pattern in rats in terms of Traditional Chinese Medicine 被引量:3
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作者 Zhangbin Yang Ting Xiang +6 位作者 Shijun Zhang Hongrui Zhan Zexiong Chen Baoguo Sun Xiaoling Chen Jingli Shi Bin Ren 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 2014年第2期214-220,共7页
OBJECTIVE: This study investigated how polypeptide 2B1 is involved in regulating and governing dampness in rat models with dampness pattern defined in terms of Traditional Chinese Medicine. METHODS: We randomly divi... OBJECTIVE: This study investigated how polypeptide 2B1 is involved in regulating and governing dampness in rat models with dampness pattern defined in terms of Traditional Chinese Medicine. METHODS: We randomly divided 48 SPF 10-week-old male Sprague-Dawley (SD) rats into a normal group, normal + Aristolochic acid I (AA-I) for 5 min group, normal + AA-I for 60 min group, dampness pattern group (DS-Group), dampness pattern + AA-I for 5 rain tern + AA-I for 60 min group, and dampness pat- group. Groups were then treated accordingly. We took out the lung, stom- ach, liver, spleen, kidney, large intestine, and small intestine tissues to detect gene and protein expres- sion of organic anion transporter polypeptide 2B1 (OATP2B1). RESULTS= Gene expression of OATP2B1 in spleen, kidney, and small intestine of rats with dampness pattern was lower than that in normal rats (P〈0.05). The gene expressions of OATP2B1 in liver, stomach, large intestine, and small intestine were lower than that in control rats at different time points after being stimulated by AA-I (P〈0.05). CONCLUSION There is coordination among multiple viscera in handling the condition of dampness, and the mechanism underlying the action may rely on regulating the expression of OATP2B1. 展开更多
关键词 Medicine Chinese traditional VISCERA Organic anion transporter polypeptide 2B1 Dampness pattern Aristolochic acid
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Darboux integrability and algebraic limit cycles for a class of polynomial differential systems
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作者 CAO JinLong LLIBRE Jaume ZHANG Xiang 《Science China Mathematics》 SCIE 2014年第4期775-794,共20页
This paper deals with the existence of Darboux first integrals for the planar polynomial differential systems x=x-y+P n+1(x,y)+xF2n(x,y),y=x+y+Q n+1(x,y)+yF2n(x,y),where P i(x,y),Q i(x,y)and F i(x,y)are homogeneous po... This paper deals with the existence of Darboux first integrals for the planar polynomial differential systems x=x-y+P n+1(x,y)+xF2n(x,y),y=x+y+Q n+1(x,y)+yF2n(x,y),where P i(x,y),Q i(x,y)and F i(x,y)are homogeneous polynomials of degree i.Within this class,we identify some new Darboux integrable systems having either a focus or a center at the origin.For such Darboux integrable systems having degrees 5and 9 we give the explicit expressions of their algebraic limit cycles.For the systems having degrees 3,5,7 and 9and restricted to a certain subclass we present necessary and sufficient conditions for being Darboux integrable. 展开更多
关键词 Darboux first integral algebraic limit cycles Abel differential equation
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An algorithm for computing the factor ring of an ideal in a Dedekind domain with finite rank
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作者 Dandan Huang Yingpu Deng 《Science China Mathematics》 SCIE CSCD 2018年第5期783-796,共14页
We give an algorithm for computing the factor ring of a given ideal in a Dedekind domain with finite rank, which runs in deterministic and polynomial time. We provide two applications of the algorithm:judging whether ... We give an algorithm for computing the factor ring of a given ideal in a Dedekind domain with finite rank, which runs in deterministic and polynomial time. We provide two applications of the algorithm:judging whether a given ideal is prime or prime power. The main algorithm is based on basis representation of finite rings which is computed via Hermite and Smith normal forms. 展开更多
关键词 deterministic polynomial-time test Dedekind domains basis representation Hermite and Smith normal forms
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A PROBABILISTIC CHARACTERIZATION OF A FAULT-TOLERANT GOSSIPING ALGORITHM
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作者 Paul PARKER 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2009年第1期88-108,共21页
Gossiping is a popular technique for probabilistic reliable multicast (or broadcast). However, it is often difficult to understand the behavior of gossiping algorithms in an analytic fashion. Indeed, existing analys... Gossiping is a popular technique for probabilistic reliable multicast (or broadcast). However, it is often difficult to understand the behavior of gossiping algorithms in an analytic fashion. Indeed, existing analyses of gossip algorithms are either based on simulation or based on ideas borrowed from epidemic models while inheriting some features that do not seem to be appropriate for the setting of gossiping. On one hand, in epidemic spreading, an infected node typically intends to spread the infection an unbounded number of times (or rounds); whereas in gossiping, an infected node (i.e., a node having received the message in question) may prefer to gossip the message a bounded number of times. On the other hand, the often assumed homogeneity in epidemic spreading models (especially that every node has equal contact to everyone else in the population) has been silently inherited in the gossiping literature, meaning that an expensive mcnlbership protocol is often needed for maintaining nodes' views. Motivated by these observations, the authors present a characterization of a popular class of fault-tolerant gossip schemes (known as "push-based gossiping") based on a novel probabilistic model, while taking the afore-mentioned factors into consideration. 展开更多
关键词 FAULT-TOLERANCE GOSSIP probabilistic broadcast reliable multicast.
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