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赚钱机器的“新”字经
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作者 李正豪 《通信世界》 2008年第12期12-13,共2页
中国移动870亿惊人利润背后隐藏着哪些秘密?这家创造了多个“世界之最”的运营巨头下一步该怎样演绎其成长故事?
关键词 机器 中国移动 “最大解” 利润
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Monotone Iterative Technique for Duffie-Epstein Type Backward Stochastic Differential Equations
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作者 孙晓君 吴玥 《Journal of Donghua University(English Edition)》 EI CAS 2005年第3期136-138,共3页
For Duffle-Epstein type Backward Stochastic Differential Equations, the comparison theorem is proved. Based on the comparison theorem, by monotone iterative technique, the existence of the minimal and maximal solution... For Duffle-Epstein type Backward Stochastic Differential Equations, the comparison theorem is proved. Based on the comparison theorem, by monotone iterative technique, the existence of the minimal and maximal solutions of the equations are proved. 展开更多
关键词 Backward Stochastic Differential Equation Conditional Expectation Maximal Solution Minimal Solution
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On design of efficient comb decimator with improved response 被引量:1
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作者 刘全 Gao Jun Huang Gaoming 《High Technology Letters》 EI CAS 2012年第2期202-207,共6页
A three-part comb decimator is presented in this paper, for the applications with severe requirements of circuit performance and frequency response. Based on the modified prime factorization method and multistage poly... A three-part comb decimator is presented in this paper, for the applications with severe requirements of circuit performance and frequency response. Based on the modified prime factorization method and multistage polyphase decomposition, an efficient non-recursive structure for the cascaded integrator-comb (CIC) decimation filter is derived. Utilizing this structure as the core part, the proposed comb decimator can not only loosen the decimation ratio's limitation, but also balance the tradeoff among the overall power consumption, circuit area and maximum speed. Further, to improve the frequency response of the comb decimator, a cos-prefilter is introduced as the preprocessing part for increasing the aliasing rejection, and an optimum sin-based filter is used as the compensation part for decreasing the passband droop. 展开更多
关键词 comb decimator cascaded integrator-comb (CIC) filter prime factorization polyphase decomposition
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Ricci Symmetries of Static Space-Times with Maximal Symmetric Transverse Spaces
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作者 M.Akbar 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第5期1229-1234,共6页
In the paper [M. Akbar and R.G. Cai, Commun. Theor. Phys. 45 (2006) 95], a complete classification is provided with at least one component of the vector field V is zero. In this paper, I consider the vector field V ... In the paper [M. Akbar and R.G. Cai, Commun. Theor. Phys. 45 (2006) 95], a complete classification is provided with at least one component of the vector field V is zero. In this paper, I consider the vector field V with all non-zero components and the static space times with maximal symmetric transverse spaces are classified according to their Ricci collineations. These are investigated for non-degenerate Ricci tensor det R ≠0. It turns out that the only collineations admitted by these spaces can be ten, seven, six or four. It also covers our previous results as a spacial case. Some new metrics admitting proper Ricci collineations are also investigated. 展开更多
关键词 Ricci collineation exact solutions of Einstein field equations maximal symmetric spaces
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Morphogenesis of Oil Palm Fruit (Elaeis guineensis Jacq.) in Mesocarp and Endocarp Development 被引量:1
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作者 Hermine Bille Ngalle Joseph Martin Bell +3 位作者 Georges Franck Ngando Ebongue Lambert Nyobe Felix Chancelin Ngangnou Godswill Ntsefong Ntsomboh 《Journal of Life Sciences》 2013年第2期153-158,共6页
This work aims to study the development of the pericarp of the fruit of Elaeis guineensis Jacq. var. dura. The thickness, the water and the oil contents of its tissues are evaluated every two weeks, from pollination t... This work aims to study the development of the pericarp of the fruit of Elaeis guineensis Jacq. var. dura. The thickness, the water and the oil contents of its tissues are evaluated every two weeks, from pollination to the maturity of the fruit. The development of the oil palm fruit takes 5.5 months. The endocarp reaches its maximum thickness at the 70th DPP (day post-pollination), with a water content of 72%. It then starts its dehydration, while sclerifying. It therefore isolates the seed at start and later protects it. The mesocarp is visible at anthesis and its water content is close to 92%. From the 100th DPP, it begins a continuous dehydration associated, from the 130th DPP, with an active lipids biosynthesis. Ultimately, the pericarp of the oil palm fruit fulfills both functions, namely to protect the seed by early sclerification of the endocarp and ensure the dissemination of the species by the high oil content of the mesocarp. A comparative anatomy of the pericarp tissues of the three genotypes.of E. guineensis Jacq., during the first three weeks of fruit development, will enhance the understanding of the primary effect of sh gene. 展开更多
关键词 Elaeis guineensis Jacq. FRUIT ENDOCARP MESOCARP development.
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Novel K-best detection algorithms for MIMO system
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作者 向星宇 仲文 《Journal of Southeast University(English Edition)》 EI CAS 2009年第1期1-5,共5页
Aiming at the optimum path excluding characteristics and the full constellation searching characteristics of the K-best detection algorithm, an improved-performance K-best detection algorithm and several reduced-compl... Aiming at the optimum path excluding characteristics and the full constellation searching characteristics of the K-best detection algorithm, an improved-performance K-best detection algorithm and several reduced-complexity K-best detection algorithms are proposed. The improved-performance K-best detection algorithm deploys minimum mean square error (MMSE) filtering of a channel matrix before QR decomposition. This algorithm can decrease the probability of excluding the optimum path and achieve better performance. The reducedcomplexity K-best detection algorithms utilize a sphere decoding method to reduce searching constellation points. Simulation results show that the improved performance K-best detection algorithm obtains a 1 dB performance gain compared to the K- best detection algorithm based on sorted QR decomposition (SQRD). Performance loss occurs when K = 4 in reduced complexity K-best detection algorithms. When K = 8, the reduced complexity K-best detection algorithms require less computational effort compared with traditional K-best detection algorithms and achieve the same performance. 展开更多
关键词 sorted QR decomposition K-best sphere decoding maximum-likelihood detection minimum mean square error
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Fifth-Nearest-Neighbor Tight-Binding Description of Electronic Structure of Graphene
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作者 尤景汉 琚伟伟 +3 位作者 李二强 蒲甜松 赵圆圆 王翚 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第6期1172-1176,共5页
An analytic expression for π and π* electronic structure of graphene is derived within the tight-binding approximation. Including up to fifth-nearest neighbors, the tight-binding description of electronic dispersio... An analytic expression for π and π* electronic structure of graphene is derived within the tight-binding approximation. Including up to fifth-nearest neighbors, the tight-binding description of electronic dispersion quite accurately reproduces the first-principle calculation result over the entire Brillouin zone. The maximal deviation of the fifth-nearest tight-binding result from the first-principle result is only 6 meV for π band, and 25 meV for π* band. This 25 meV deviation is only one-tenth of the maximal deviation of the third-nearest tight-binding result. It is more important that the fitted parameters exponentially approach to zero as the distance between interacting atoms increases. 展开更多
关键词 GRAPHENE electronic structure tight-binding approximation
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Ground stress and its impact on the stability of the surrounding rock in the Lüliang mining area 被引量:5
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作者 Wang Lianguo Lu Yinlong 《Mining Science and Technology》 EI CAS 2011年第5期625-630,共6页
Ground stress is the fundamental cause of deformation and failure during underground structural engineering. Field stress measurements in the main coal bed in the Lueliang mining area were made by the bore hole, stres... Ground stress is the fundamental cause of deformation and failure during underground structural engineering. Field stress measurements in the main coal bed in the Lueliang mining area were made by the bore hole, stress relief method. From these data the ground stress distribution of the mining area was obtained. The relationship between the horizontal principal stress and the deformation and failure of a roadway is discussed with an engineering example. The results indicate that horizontal stress dominates in the shallow crust in the Ltiliang mining area. Roadways at different angles to the maximum principal stress have different levels of stress concentration. This leads to a significant difference in stability of the corresponding roadways. These research results provide an important criterion for determining roadway position and direction, stope layout, and roadway support design. 展开更多
关键词 Ground stress measurementBoring stress-relief methodDistribution ruleStability of surrounding rock
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Maximum Effective Hole Mathematical Modei and Exact Solution for Commingled Reservoir 被引量:2
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作者 孙贺东 刘磊 +1 位作者 周芳德 高承泰 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2003年第5期550-554,共5页
The maximum effective hole-diameter mathematical modei describing the flow of slightly compressible fluid through a commingled reservoir was solved rigorously with consideration of wellbore storage and different skin ... The maximum effective hole-diameter mathematical modei describing the flow of slightly compressible fluid through a commingled reservoir was solved rigorously with consideration of wellbore storage and different skin factors. The exact solutions for wellbore pressure and the production rate obtained from layer j for a well production at a constant rate from a radial drainage area with infinite and constant pressure and no flow outer boundary condition were expressed in terms of ordinary Bessel functions. These solutions were computed numerically by the Crump's numerical inversion method and the behavior of systems was studied as a function of various reservoir parameters. The modei was compared with the real wellbore radii modei. The new modei is numerically stable when the skin factor is positive and negative, but the real wellbore radii modei is numerically stable only when the skin factor is positive. 展开更多
关键词 well-testing mathematical model effective hole diameter layered reservoir
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Application of a wire-guided side-viewing duodenoscope in total esophagectomy with colonic interposition
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作者 Chin-Yuan Yii Jen-Wei Chou +1 位作者 Yen-Chun Peng Wai-Keung Chow 《World Journal of Gastroenterology》 SCIE CAS CSCD 2011年第13期1787-1790,共4页
Therapeutic endoscopic retrograde cholangiopancreatography (ERCP) is the mainstay treatment for bile duct disease. The procedure is difficult per se, especially when a side-viewing duodenoscope is used, and when the p... Therapeutic endoscopic retrograde cholangiopancreatography (ERCP) is the mainstay treatment for bile duct disease. The procedure is difficult per se, especially when a side-viewing duodenoscope is used, and when the patient has altered anatomical features, such as colonic interposition. Currently, there is no consensus on the standard approach for therapeutic ERCP in patients with total esophagectomy and colonic interposition. We describe a novel treatment design that involves the use of a side-viewing duodenoscope to perform therapeutic ERCP in patients with total esophagectomy and colonic interposition. A gastroscope was initially introduced into the interposed colon and a radio-opaque standard guidewire was advanced to a distance beyond the papilla of Vater, before the gastroscope was withdrawn. A sideviewing duodenoscope was then introduced along the guidewire under fluoroscopic guidance. After cannulation into the papilla of Vater, endoscopic retrograde chol-angiography (ERC) revealed a filling defect (maximum diameter: 15 cm) at the distal portion of the common bile duct (CBD). This defect was determined to be a stone, which was successfully retrieved by a Dormia basket after complete sphincterotomy. With this treatment design, it is possible to perform therapeutic ERCP in patients with colonic interposition, thereby precluding the need for percutaneous drainage or surgery. 展开更多
关键词 Wire-guided Duodenoscope Endoscopic retrograde cholangiopancreatography ESOPHAGECTOMY Interposition of colon
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Supply chain management research directions for future development
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作者 WenyanWang 《International Journal of Technology Management》 2015年第5期118-120,共3页
With the rapid development of electronic commerce, supply chain management is facing more and more new challenges. Therefore, it is particularly important to study the development of clear direction of supply chain. H... With the rapid development of electronic commerce, supply chain management is facing more and more new challenges. Therefore, it is particularly important to study the development of clear direction of supply chain. However, the supply chain is composed of different interest subjects, each subject in order to achieve the maximization of their own interests and adopt different measures, is a complex, huge system, has brought the huge challenge to the supply chain management. In this paper, the research on Supply Chain Management in the current situation, characteristics and the modem supply chain management are summarized, and combined with new challenges of supply chain management to predict future research direction is the development of supply chain management, in order to make the supply chain management to the greatest extent satisfy the consumer e-commerce mode increasingly popular. 展开更多
关键词 electronic commerce supply chain management complex system consumption mode future development direction
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Generalized Maximum Likelihood Noncoherent Block Detection for Decode-and-Forward Relay Systems
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作者 HE Yucheng QIAO Ying ZHOU Lin 《China Communications》 SCIE CSCD 2014年第4期163-171,共9页
This paper considers noncoherent cooperative decode-and-forward(DF) halfduplex multi-branch relay systems.Each relay branch is modeled as a probabilistic transition system at the last hop,and thus it can be considered... This paper considers noncoherent cooperative decode-and-forward(DF) halfduplex multi-branch relay systems.Each relay branch is modeled as a probabilistic transition system at the last hop,and thus it can be considered as a relaying chain comprising multi-hop relays.An approximation to the generalized maximum likelihood(ML) noncoherent block detection is derived for uncoded M-ary modulation in a faded noisy environment.In particular,the derived noncoherent block detection in a noiseless case is equivalent to a multichannel reception with full diversity.Furthermore,the generalized detection is extended specifically to block coded M-ary phase shift keying(MPSK) modulation.For a DF three node relay system using block coded quadrature phase shift keying(QPSK),simulation results are provided to examine the end-to-end error performance of the noncoherent detection with considering the effects of network geometry and power allocation,respectively.It is shown that under a fixed power allocation,a proper relay placement can yield near full diversity for large signal-to-noise ratio. 展开更多
关键词 cooperative communications decode-and- forward MPSK noncoherent detection
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Modified Augmented Lagrange Multiplier Methods for Large-Scale Chemical Process Optimization 被引量:6
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作者 梁昔明 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2001年第2期167-172,共6页
Chemical process optimization can be described as large-scale nonlinear constrained minimization. The modified augmented Lagrange multiplier methods (MALMM) for large-scale nonlinear constrained minimization are studi... Chemical process optimization can be described as large-scale nonlinear constrained minimization. The modified augmented Lagrange multiplier methods (MALMM) for large-scale nonlinear constrained minimization are studied in this paper. The Lagrange function contains the penalty terms on equality and inequality constraints and the methods can be applied to solve a series of bound constrained sub-problems instead of a series of unconstrained sub-problems. The steps of the methods are examined in full detail. Numerical experiments are made for a variety of problems, from small to very large-scale, which show the stability and effectiveness of the methods in large-scale problems. 展开更多
关键词 modified augmented Lagrange multiplier methods chemical engineering optimization large-scale non- linear constrained minimization numerical experiment
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Ricci Collineations of Static Space Times with Maximal Symmetric Transverse Spaces
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作者 M. Akbar CAI Rong-Gen 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第1期95-104,共10页
A complete classification of static space times with maximal symmetric transverse spaces is provided, according to their Ricci collineations. The classification is made when one component of Ricci collineation vector ... A complete classification of static space times with maximal symmetric transverse spaces is provided, according to their Ricci collineations. The classification is made when one component of Ricci collineation vector field V is non-zero (cases 1 - 4), two components of V are non-zero (cases 5 - 10), and three components of V are non-zero (cases 11 - 14), respectlvily. Both non-degenerate (detRab ≠ 0) as well as the degenerate (det Rab = 0) cases are discussed and some new metrics are found. 展开更多
关键词 Ricci collineations exact solutions of Einstein field equations maximal symmetric spaces
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Effective Channel Length Degradation under Hot-Carrier Stressing
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作者 Anucha Ruangphanit Kunagone Kiddee +2 位作者 Rangson Muanghlua Surasak Niemcharoen Ampom Poyai 《Computer Technology and Application》 2011年第11期926-929,共4页
This article describes the effective channel length degradation under hot carrier stressing. The extraction is based on the IDs-Vcs characteristics by maximum transconductance (maximum slope of IDs & VGS) in the li... This article describes the effective channel length degradation under hot carrier stressing. The extraction is based on the IDs-Vcs characteristics by maximum transconductance (maximum slope of IDs & VGS) in the linear region. The transconductance characteristics are determine for the several devices of difference drawn channel length. The effective channel length of submicron LDD (Lightly Doped Drain) NMOSFETs (Metal Oxide Semiconductor Field Effect Transistor) under hot carrier stressing was measured at the stress time varying from zero to 10,000 seconds. It is shown that the effective channel length was increased with time. This is caused by charges trapping in the oxide during stress. The increased of effective channel length (△Leff) is seem to be increased sharply as the gate channel length is decrease. 展开更多
关键词 NMOSFETs (metal oxide semiconductor field effect transistor) effective channel length hot carrier stressing
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Solution and Coupled Minimal-Maximal Quasi-Solutions of Nonlinear Non-monotone Operator Equations in Banach Spaces
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作者 张克梅 解学军 《Journal of Mathematical Research and Exposition》 CSCD 北大核心 2003年第1期47-52,共6页
Abstrac In this paper, we discuss the existence of the solution and coupled minimal and maximal quasi-solutions for nonlinear non-monotone operator equation x = A(x, x), improved and generalized many relevant results.
关键词 monotone operator coupled quasi-solutions cone.
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ON THE PRIORI ESTIMATE OF MAXIMUM MODULUS OF SOLUTIONS TO A SYSTEM OF DIAGONALLY DEGENERATE ELLIPTIC EQUATIONS 被引量:1
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作者 WANG Xiangdong RONG Haiwu LIANG Xiting (Mathematics Department of Foshan University, Foshan 528000, China) 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2003年第4期446-452,共7页
In this paper we first give an a priori estimate of maximum modulus ofsolutions for a class of systems of diagonally degenerate elliptic equations in the case of p > 2.
关键词 system of diagonally degenerate elliptic equations generalized solution priori estimate
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PERIODIC BOUNDARY VALUE PROBLEMS FOR IMPULSIVE INTEGRO-DIFFERENTIAL EQUATIONS OF MIXED TYPE IN BANACH SPACES 被引量:12
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作者 LIUXINZHI GUODAJUN 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 1998年第4期517-528,共12页
This paper investigates periodic boundary value problem for first order nonlinear impulsive integro-differelltial equations of mixed type in a Banach space. By establishing a comparison result, criteria on the existen... This paper investigates periodic boundary value problem for first order nonlinear impulsive integro-differelltial equations of mixed type in a Banach space. By establishing a comparison result, criteria on the existence of maximal and minimal solutions are obtained. 展开更多
关键词 Periodic boundary Value problem Impulsive integro-differential equation Ordered Banach space Maximal solution Minimal solution
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A Study of 3D Aerodynamic Design for a Transonic Compressor Blading Optimized by the Locations of Aerofoil Maximum Thickness and Maximum Camber 被引量:1
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作者 Naixing Chen Hongwu Zhang Yanji Xu Weiguang HuangInstitute of Engineering Thermophysics, Chinese Academy of Sciences, P.O. Box 2706, Beijing 100080, 《Journal of Thermal Science》 SCIE EI CAS CSCD 2003年第3期198-203,共6页
A design procedure for improving the efficiency of a transonic compressor blading was proposed based on a rapid generation method for three-dimensional blade configuration and computational meshes, a three-dimensional... A design procedure for improving the efficiency of a transonic compressor blading was proposed based on a rapid generation method for three-dimensional blade configuration and computational meshes, a three-dimensional Navier-Stokes solver and an optimization approach. The objective of the present paper is to design a transonic compressor blading optimized only by selection of the locations of maximum camber and maximum thickness for the airfoils at different span heights and to study how do these two design parameters affect the blade performance. The blading configuration and the computational meshes can be obtained very rapidly for any given combination of maximum camber and maximum thickness. The computational grid system generated is used for the Navier-Stokes solution to predict adiabatic efficiency, total pressure ratio and flow rate. As a main result of the optimization, adiabatic efficiency was successfully improved. 展开更多
关键词 axial transonic compressor 3D aerodynamic design optimization N.S. solver rapid generation of computational meshes
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BLOW-UP OF SOLUTIONS OF THE IGNITION MODEL
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作者 LI Yarding (Faculty of Science, Xi’an Jiaotong University, Xi’an 710049, China)WU Jianhua (Department of Mathematics, Shaanxi Normal University, Xi’an 710062, China) 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2002年第3期278-281,共4页
By use of maximum principle and auxiliary function method,the paper discusses the blow-up sets of the solutions of the ignition model in two cases,It is obtained that the solutions blow up in single point in nonsymmet... By use of maximum principle and auxiliary function method,the paper discusses the blow-up sets of the solutions of the ignition model in two cases,It is obtained that the solutions blow up in single point in nonsymmetric case and that the solutions blow up totally or at a couple of points in symmetric case. 展开更多
关键词 Blow-up set ignition model maximum principle.
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