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Local State Capacity and Uneven Taxation across Industrial Firms
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作者 Linke Hou Zhikuo Liu +1 位作者 Qi Zhang Xiaolu Zhao 《China & World Economy》 2024年第3期191-214,共24页
In this research we investigate the association between local state capacity(LSC)and effective tax burdens(ETBs)on industrial firms within counties between 1998 and 2013.The LSC measures a state's capacity for pol... In this research we investigate the association between local state capacity(LSC)and effective tax burdens(ETBs)on industrial firms within counties between 1998 and 2013.The LSC measures a state's capacity for policy implementation and specifically its ability to acquire low-cost agricultural land for nonagricultural(industrial or commercial)purposes.Based on China's government-led development experience since the 1990s,we draw on two unique household survey datasets to capture LSC at county level.We find robust evidence that greater LSC was associated with much lower ETBs on large industrial firms.This taxation pattern implies local government's primary reliance on larger manufacturing firms,while the ETBs for small-and-medium enterprises are not as prominently addressed.This research highlights that LSC can affect both the amount of revenue a local government can generate and the methods it uses to collect these revenues. 展开更多
关键词 China effective tax burdens land requisition local government local state capacity
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Observation of flat-band localized state in a one-dimensional diamond momentum lattice of ultracold atoms
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作者 曾超 石悦然 +5 位作者 毛一屹 武菲菲 谢岩骏 苑涛 戴汉宁 陈宇翱 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期212-217,共6页
We investigated the one-dimensional diamond ladder in the momentum lattice platform. By inducing multiple twoand four-photon Bragg scatterings among specific momentum states, we achieved a flat band system based on th... We investigated the one-dimensional diamond ladder in the momentum lattice platform. By inducing multiple twoand four-photon Bragg scatterings among specific momentum states, we achieved a flat band system based on the diamond model, precisely controlling the coupling strength and phase between individual lattice sites. Utilizing two lattice sites couplings, we generated a compact localized state associated with the flat band, which remained localized throughout the entire time evolution. We successfully realized the continuous shift of flat bands by adjusting the corresponding nearest neighbor hopping strength, enabling us to observe the complete localization process. This opens avenues for further exploration of more complex properties within flat-band systems, including investigating the robustness of flat-band localized states in disordered flat-band systems and exploring many-body localization in interacting flat-band systems. 展开更多
关键词 diamond lattice flat band momentum lattice localized state
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Local-State Routing in Satellite Constellation Networks from the Perspective of Complex Network
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作者 Xin Xu Jun Cai +2 位作者 Aijun Liu Chaoying Dong Chen Han 《China Communications》 SCIE CSCD 2023年第7期72-88,共17页
Routing algorithms in satellite constellation networks usually make use of the local state information to adapt to the topology and traffic dynamics,since it’s difficult to obtain the global states in time due to the... Routing algorithms in satellite constellation networks usually make use of the local state information to adapt to the topology and traffic dynamics,since it’s difficult to obtain the global states in time due to the spatial large-scale feature of constellation networks.Furthermore,they use different range of local states and give these states distinct weights.However,the behind design criterion is ambiguous and often based on experience.This paper discusses the problem from the perspective of complex network.A universal local-state routing model with tunable parameters is presented to generalize the common characteristics of local-state routing algorithms for satellite constellation networks.Based on this,the impacts of localstate routing algorithms on performance and the correlation between routing and traffic dynamics are analyzed in detail.Among them,the tunable parameters,the congestion propagation process,the critical packet sending rate,and the network robustness are discussed respectively.Experimental results show that routing algorithms can achieve a satisfactory performance by maintaining a limited state awareness capability and obtaining the states in a range below the average path length.This provides a valuable design basis for routing algorithms in satellite constellation networks. 展开更多
关键词 satellite constellation local state routing traffic dynamics complex networks ROBUSTNESS
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Local density of optical states calculated by the mode spectrum in stratified media
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作者 傅廷 陈静瑄 +5 位作者 王学友 戴迎秋 周旭彦 王宇飞 王明金 郑婉华 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第4期135-141,共7页
The local density of optical states(LDOS)is an important physical concept,which can characterize the spontaneous emission of microcavities.In order to calculate the LDOS,the relationship between the mode spectrum and ... The local density of optical states(LDOS)is an important physical concept,which can characterize the spontaneous emission of microcavities.In order to calculate the LDOS,the relationship between the mode spectrum and the LDOS is established.Then,based on the transfer matrix method and the effective resonator model,the leaky loss of the leaky mode and the mode spectrum in the one-dimensional photonic bandgap crystal waveguide are calculated,results of which indicate that the mode spectrum can characterize the leaky loss of the leaky mode.At last,the density of optical states(DOS),and the LDOS in each layer are calculated.The partial DOS and the partial LDOS in the quantum well,related to the fundamental leaky mode,can be used to find out the optimal location of the quantum well in the defect layer to couple more useful photons into the lasing mode for lasers. 展开更多
关键词 local density of optical states mode spectrum transfer matrix method
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Different localized states of travelling-wave convection in a rectangular container 被引量:2
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作者 李国栋 黄永念 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第12期2984-2988,共5页
We have performed numerical simulations of localized travelling-wave convection in a binary fluid mixture heated from below in a long rectangular container. Calculations are carried out in a vertical cross section of ... We have performed numerical simulations of localized travelling-wave convection in a binary fluid mixture heated from below in a long rectangular container. Calculations are carried out in a vertical cross section of the rolls perpendic- ular to their axes. For a negative enough separation ratio, two types of quite different confined states were documented by applying different control processes. One branch of localized travelling waves survives only in a very narrow band within subcritical regime, while another branch straddles the onset of convection existing both in subcritical and super- critical regions. We elucidated that concentration field and its current are key to understand how confined convection is sustained when conductive state is absolutely unstable, The weak structures in the conducting region are demonstrated too. 展开更多
关键词 binary fluid mixture travelling-wave convection localized states
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Characteristics of local photonic state density in an infinite two-dimensional photonic crystal 被引量:1
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作者 周云松 王雪华 +1 位作者 顾本源 王福合 《Chinese Physics B》 SCIE EI CAS CSCD 2005年第11期2241-2245,共5页
The local density of photonic states (LDPS) of an infinite two-dimensional (2D) photonic crystal (PC) composed of rotated square-pillars in a 2D square lattice is calculated in terms of the plane-wave expansion ... The local density of photonic states (LDPS) of an infinite two-dimensional (2D) photonic crystal (PC) composed of rotated square-pillars in a 2D square lattice is calculated in terms of the plane-wave expansion method in a combination with the point group theory. The calculation results show that the LDPS strongly depends on the spatial positions. The variations of the LDPS as functions of the radial coordinate and frequency exhibit “mountain chain” structures with sharp peaks. The LDPS with large value spans a finite area and falls abruptly down to small value at the position corresponding to the interfaces between two different refractive index materials. The larger/lower LDPS occurs inward the lower/larger dielectric-constant medium. This feature can be well interpreted by the continuity of electricdisplacement vector at the interface. In the frequency range of the pseudo-PBG (photonic band gap), the LDPS keeps very low value over the whole Wiger-Seitz cell. It indicates that the spontaneous emission in 2D PCs cannot be prohibited completely, but it can be inhibited intensively when the resonate frequency falls into the pseudo-PBG. 展开更多
关键词 local density of photonic states two-dimensional photonic crystal spontaneous emission
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One-dimensional method of investigating the localized states in armchair graphene-like nanoribbons with defects
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作者 谢阳 胡智健 +2 位作者 丁文浩 吕小龙 谢航 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第12期516-525,共10页
In this paper we propose a type of new analytical method to investigate the localized states in the armchair graphene-like nanoribbons. The method is based on the tight-binding model and with a standing wave assumptio... In this paper we propose a type of new analytical method to investigate the localized states in the armchair graphene-like nanoribbons. The method is based on the tight-binding model and with a standing wave assumption. The system of armchair graphene-like nanoribbons includes the armchair supercells with arbitrary elongation-type line defects and the semi-infinite nanoribbons. With this method, we analyze many interesting localized states near the line defects in the graphene and boron-nitride nanoribbons. We also derive the analytical expressions and the criteria for the localized states in the semi-infinite nanoribbons. 展开更多
关键词 graphene nanoribbons tight-binding model energy band localized states
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Localized states of flattened quantum elliptic rings and their optical properties
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作者 司徒树平 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第4期1609-1613,共5页
A flattened elliptic ring containing an electron is studied. The emphasis is placed on clarifying the effect of the flattening. The localized states are classified into four types according to their inherent nodes. Wh... A flattened elliptic ring containing an electron is studied. The emphasis is placed on clarifying the effect of the flattening. The localized states are classified into four types according to their inherent nodes. When the ring becomes more flattened, the total probability of dipole absorption of each state is found to be reduced. Furthermore, each spectral line of absorption is found to shift towards red and may split into a few lines, and these lines as a whole become more diffusive. 展开更多
关键词 flattened quantum elliptic ring localized state dipole absorption
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Localized electronic states in gaps on hole-net structures of silicon
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作者 黄伟其 吕泉 +2 位作者 张荣涛 王晓允 于示强 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第11期5066-5071,共6页
Hole-net structure silicon is fabricated by laser irradiation and annealing, on which a photoluminescence (PL) band in a the region of 650-750 nm is pinned and its intensity increases obviously after oxidation. It i... Hole-net structure silicon is fabricated by laser irradiation and annealing, on which a photoluminescence (PL) band in a the region of 650-750 nm is pinned and its intensity increases obviously after oxidation. It is found that the PL intensity changes with both laser irradiation time and annealing time. Calculations show that some localized states appear in the band gap of the smaller nanocrystal when Silo bonds or Si-O-Si bonds are passivated on the surface. It is discovered that the density and the number of Si=O bonds or Si-O-Si bonds related to both the irradiation time and the annealing time obviously affect the generation of the localized gap states of hole-net silicon, by which the production of stimulated emission through controlling oxidation time can be explained. 展开更多
关键词 hole-net silicon passivated bonds localized gap states
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Vortex bound states influenced by the Fermi surface anisotropy 被引量:1
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作者 方德龙 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第3期497-501,共5页
The spatial distribution of vortex bound states is often anisotropic,which is correlated with the underlying property of materials.In this work,we examine the effects of Fermi surface anisotropy on vortex bound states... The spatial distribution of vortex bound states is often anisotropic,which is correlated with the underlying property of materials.In this work,we examine the effects of Fermi surface anisotropy on vortex bound states.The large-scale calculation of vortex bound states is introduced in the presence of fourfold or twofold Fermi surface by solving the Bogoliubov–de Gennes(BdG)equations.Two kinds of quasiparticles’behaviors can be extracted from the local density of states(LDOS)around a vortex.The angle-dependent quasiparticles will move from high energy to low energy when the angle varies from curvature maxima to minima of the Fermi surface,while the angle-independent quasiparticles tend to stay at a relatively higher energy.In addition,the weight of angle-dependent quasiparticles can be enhanced by the increasing anisotropy degree of Fermi surface. 展开更多
关键词 VORTEX ANISOTROPY Fermi surface local density of states
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Spontaneous-emission control by local density of states of photonic crystal cavity
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作者 江斌 张冶金 +3 位作者 周文君 陈微 刘安金 郑婉华 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第2期271-276,共6页
The local density of states (LDOS) of two-dimensional square lattice photonic crystal (PhC) defect cavity is studied. The results show that the LDOS in the centre is greatly reduced, while the LDOS at the point of... The local density of states (LDOS) of two-dimensional square lattice photonic crystal (PhC) defect cavity is studied. The results show that the LDOS in the centre is greatly reduced, while the LDOS at the point off the centre (for example, at the point (0.3a, 0.4a), where a is the lattice constant) is extremely enhanced. Further, the disordered radii are introduced to imitate the real devices fabricated in our experiment, and then we study the LDOS of PhC cavity with configurations of different disordered radii. The results show that in the disordered cavity, the LDOS in the centre is still greatly reduced, while the LDOS at the point (0.3a, 0.4a) is still extremely enhanced. It shows that the LDOS analysis is useful. When a laser is designed on the basis of the square lattice PhC rod cavity, in order to enhance the spontaneous emission, the active materials should not be inserted in the centre of the cavity, but located at positions off the centre. So LDOS method gives a guide to design the positions of the active materials (quantum dots) in the lasers. 展开更多
关键词 spontaneous emission local density of states photonic crystal cavity
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Four-cluster chimera state in non-locally coupled phase oscillator systems with an external potential 被引量:1
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作者 朱云 郑志刚 杨俊忠 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第10期169-175,共7页
Dynamics of a one-dimensional array of non-locally coupled Kuramoto phase oscillators with an external potential is studied. A four-cluster chimera state is observed for the moderate strength of the external potential... Dynamics of a one-dimensional array of non-locally coupled Kuramoto phase oscillators with an external potential is studied. A four-cluster chimera state is observed for the moderate strength of the external potential. Different from the clustered chimera states studied before, the instantaneous frequencies of the oscillators in a synchronized cluster are different in the presence of the external potential. As the strength of the external potential increases, a bifurcation from the two-cluster chimera state to the four-cluster chimera states can be found. These phenomena are well predicted analytically with the help of the Ott-Antonsen ansatz. 展开更多
关键词 chimera state non-local coupling Kuramoto oscillators and Ott-Antonsen ansatz
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Local density of states of dc-biased superlattices with time-dependent imperfection
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作者 阎维贤 李向荣 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第4期822-827,共6页
The single-particle Green's function for a dc-biased superlattices with single impurity potential varying harmonically with time has been obtained in the framework of U(t,t') method and Floquet-Green's function. ... The single-particle Green's function for a dc-biased superlattices with single impurity potential varying harmonically with time has been obtained in the framework of U(t,t') method and Floquet-Green's function. The calculation of the local density of states shows that new states will emerge between the resonant Wannier-Stark states as a result of the intervention of time-dependent impurity potential, and the increase in electric field strength of impurity will result in the growing of the number of new states between the gaps of neighbouring Stark ladders. 展开更多
关键词 local density of states Floquet-Green's function defects and impurity
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State vector evolution localized over the edges of a square tight-binding lattice
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作者 何良明 石端文 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第3期1214-1220,共7页
We study thc time evolution of a state vector in a square tight-binding lattice, focusing on its evolution localized over the system surfaces. In this tight-binding lattice, the energy of atomic orbital centred at sur... We study thc time evolution of a state vector in a square tight-binding lattice, focusing on its evolution localized over the system surfaces. In this tight-binding lattice, the energy of atomic orbital centred at surface site is different from that at the interior (bulky) site by an energy shift U. It is shown that for the state vector initially localized on a surface, there exists an exponential law (y = ae^x/b + Y0) determined by the absolute value of the energy shift, |U|, which describes the transition of the state evolving on the square tight-binding lattice, from delocalized over the whole lattice to localized over the surfaces. 展开更多
关键词 Anderson localization surface states state vector evolution
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Local Invariants for a Class of Tripartite Quantum Mixed States
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作者 WANG Xiao-Hong 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第2期262-266,共5页
我们在本地单一的转变下面学习分成三部分的混合状态的等价。为在 C~K 直接 X C~MdirectX C~N 合成系统的分成三部分的量状态的一个类的非局部的性质被调查,在为这些状态的本地单一的转变下面的 invariants 的一个完全的集合被介绍。... 我们在本地单一的转变下面学习分成三部分的混合状态的等价。为在 C~K 直接 X C~MdirectX C~N 合成系统的分成三部分的量状态的一个类的非局部的性质被调查,在为这些状态的本地单一的转变下面的 invariants 的一个完全的集合被介绍。如果并且仅当,二个这些状态是局部地相等的,这被显示出所有这些 invariants 有一样的价值。 展开更多
关键词 局部不变量 三重量子态 局部整体转化 三重混合态
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A note on local unitary equivalence of isotropic-like states
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作者 张廷桂 华波波 +2 位作者 李明 赵明镜 杨红 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第12期228-231,共4页
We consider the local unitary equivalence of a class of quantum states in a bipartite case and a multipartite case. The necessary and sufficient condition is presented. As special cases, the local unitary equivalent c... We consider the local unitary equivalence of a class of quantum states in a bipartite case and a multipartite case. The necessary and sufficient condition is presented. As special cases, the local unitary equivalent classes of isotropic state and Werner state are provided. Then we study the local unitary similar equivalence of this class of quantum states and analyze the necessary and sufficient condition. 展开更多
关键词 mixed state local unitary equivalence local unitary similar equivalence
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Estimation the Density of Localized State Glassy Se_(100-x)Zn_(x) Thin Films by Using Space Charge Limited Conduction Measurement
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作者 Mohd.Nasir M.Zulfequar 《New Journal of Glass and Ceramics》 2012年第2期91-97,共7页
The dc conductivity in vacuum evaporated amorphous thin films of the glassy alloys Se100–xZnx(2 ≤ x ≤ 20) are meas-ured in the temperature range (308 - 388 K). The dc conductivity (σdc) is increases with increased... The dc conductivity in vacuum evaporated amorphous thin films of the glassy alloys Se100–xZnx(2 ≤ x ≤ 20) are meas-ured in the temperature range (308 - 388 K). The dc conductivity (σdc) is increases with increased of Zn concentration in the glassy alloys. The activation energy (ΔE) decreases with increase of Zn content. The conduction is explained on the basis of localized state in the mobility gap. To study the effect of electric field, a Current-Voltage characteristic has been measured at various fixed temperatures. The Current-Voltage data are fitted into the theory of space charge limited conduction in case of uniform distribution of traps in mobility gap at high electric fields (E ~104 V/cm) of these materials. The density of localized state (g0) are estimated by fitting in theory of space charge limited conduction (SCLC) at the temperature range of (352 - 372 K) in the glassy Se100–xZnx. The density of localized state (0) near the Fermi level are increases with increase of Zn concentration in the (Se100–xZnx) thin films and explain on the basis of increase of the Zn-Se bond. 展开更多
关键词 Density of localized state dc Conductivity Activation Energy(△E) SEM Thin Films
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The “Non-Locality” of Entangled States Is Seeming Phenomenon
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作者 Marat Guryev 《Journal of Applied Mathematics and Physics》 2017年第9期1791-1796,共6页
EPR raised fundamental problems of non-locality (NL) in the case of entangled states (ES) 82 years ago. These problems were not solved until now. EPR and their followers used and would continue to use calculation meth... EPR raised fundamental problems of non-locality (NL) in the case of entangled states (ES) 82 years ago. These problems were not solved until now. EPR and their followers used and would continue to use calculation methods that were available at that time. However, we can easily explain this observable NL as a trivial result of conservation laws (CL) within modern quantum mechanics (MQM). But application of CL requires materialistic descriptions of reality in a micro world in contrast to so-called quantum measurement theory (QMT), which was created mainly in the times of EPR and is widely accepted until now. We have to use a materialistic description, just as many physicists who actually work with high precision do by default. In this article, practical examples are given for real, precise measurements of wave functions of molecules and crystals, which, of course, were not known to EPR and were not noticed by their followers. We should acknowledge that QMT is merely an unneeded complication of simple relations of MQM. NL is the seeming result of these complications. 展开更多
关键词 NON-localITY ENTANGLED states Quantum MEASUREMENT Theory EPR Electron DIFFRACTION Neutron DIFFRACTION y - RAY DIFFRACTION MEASUREMENT of Wave Function
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Relationship between the Local Vibration Mode Characteristics and the Charge State of Carbon Acceptor in GaAs
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作者 杨瑞霞 李光平 +1 位作者 王琴 何秀坤 《Rare Metals》 SCIE EI CAS CSCD 1992年第3期207-211,共5页
The local vibration mode(LVM)of carbon acceptor in GaAs is studied by measuring directly the change in LVM absorption with a NIC-170 SX FT-IR spectrometer.The change in the charge state of carbon acceptor and the temp... The local vibration mode(LVM)of carbon acceptor in GaAs is studied by measuring directly the change in LVM absorption with a NIC-170 SX FT-IR spectrometer.The change in the charge state of carbon acceptor and the temperature dependence of the LVM absorption were investigated also.The contents of the impurities other than carbon were estimated by secondary ion mass spectrometry.It is observed that the frequency,the spectral form and the integrated absorption of the LVM are not affected by the change in charge state of car- bon acceptor. 展开更多
关键词 local vibration mode GAAS Charge state Carbon acceptor ABSORPTION
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Rapid State Augmentation for Compressed EKF-Based Simultaneous Localization and Mapping 被引量:1
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作者 窦丽华 张海强 +1 位作者 陈杰 方浩 《Journal of Beijing Institute of Technology》 EI CAS 2009年第2期192-197,共6页
A new method for speeding up the state augment operations involved in the compressed extended Kalman filter-based simultaneous localization and mapping (CEKF-SLAM) algorithm was proposed. State augment usually requi... A new method for speeding up the state augment operations involved in the compressed extended Kalman filter-based simultaneous localization and mapping (CEKF-SLAM) algorithm was proposed. State augment usually requires a fully-updated state eovariance so as to append the information of newly observed landmarks, thus computational volume increases quadratically with the number of landmarks in the whole map. It was proved that state augment can also be achieved by augmenting just one auxiliary coefficient ma- trix. This method can yield identical estimation results as those using EKF-SLAM algorithm, and computa- tional amount grows only linearly with number of increased landmarks in the local map. The efficiency of this quick state augment for CEKF-SLAM algorithm has been validated by a sophisticated simulation project. 展开更多
关键词 simultaneous localization and mapping (SLAM) extended Kalman filter state augment compu- tational volume
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