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持股锁定期、信息动量与IPO抑价 被引量:10
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作者 熊维勤 孟卫东 周孝华 《中国管理科学》 CSSCI 2007年第1期121-129,共9页
基于IPO首日抑价可以产生信息动量效应,进而增加二级市场对新股需求的假设,建立了锁定期与IPO抑价关系模型。对模型的分析表明,当抑价所产生的边际信息动量足够高时,IPO抑价为锁定比例和锁定期的增函数。应用1998至2004年137只实施了锁... 基于IPO首日抑价可以产生信息动量效应,进而增加二级市场对新股需求的假设,建立了锁定期与IPO抑价关系模型。对模型的分析表明,当抑价所产生的边际信息动量足够高时,IPO抑价为锁定比例和锁定期的增函数。应用1998至2004年137只实施了锁定规则的IPO数据进行了检验,实证结果支持模型的假设和结论,表明锁定期并未起到传递公司质量信息的作用,抑制二级市场投资者对新股的狂热情绪,或者延长锁定期有可能使其达到这一目的。 展开更多
关键词 锁定期 信息动量 IPO抑价
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A Novel System Model based on Cost-prediction for Spectrum Leasing in Cognitive Radio 被引量:1
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作者 Wang Weidong Wang Ben Zhang Yinghai Zhao Xinlei Wang Shoufeng 《China Communications》 SCIE CSCD 2010年第2期32-41,共10页
In current researches on spectrum leasing, Common model and Property-right model are two main approaches to dynamic spectrum sharing. However, Common model does not consider the obligation of Primary System (PS) and i... In current researches on spectrum leasing, Common model and Property-right model are two main approaches to dynamic spectrum sharing. However, Common model does not consider the obligation of Primary System (PS) and is unfair to Secondary System (SS), while the cooperation based on Property-rights model has problems on its feasibility. This paper proposes a novel system model, in which a Cost-Prediction scheme for Spectrum Leasing (CPSL scheme) is designed to forecast the cost that PS would pay for leasing spectrum. Cost Function is introduced as a criterion to evaluate the potential cost of spectrum leasing for PS. The simulation results show that compared with Common model based scheme, CPSL scheme substantially improves the QoS of the delay-sensitive traffic in SS at the cost of a small degradation of PS performance. 展开更多
关键词 cognitive radio spectrum leasing cost prediction dynamic spectrum sharing CPSL
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Considerations when using the activPAL monitor in field-based research with adult populations 被引量:5
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作者 Charlotte L.Edwardson Elisabeth A.H.Winkler +4 位作者 Danielle H.Bodicoat Tom Yates Melanie J.Davies David W.Dunstan Genevieve N.Healy 《Journal of Sport and Health Science》 SCIE 2017年第2期162-178,共17页
Research indicates that high levels of sedentary behavior(sitting or lying with low energy expenditure) are adversely associated with health. A key factor in improving our understanding of the impact of sedentary beha... Research indicates that high levels of sedentary behavior(sitting or lying with low energy expenditure) are adversely associated with health. A key factor in improving our understanding of the impact of sedentary behavior(and patterns of sedentary time accumulation) on health is the use of objective measurement tools that collect date and time-stamped activity information. One such tool is the activP AL monitor. This thigh-worn device uses accelerometer-derived information about thigh position to determine the start and end of each period spent sitting/lying, standing, and stepping, as well as stepping speed, step counts, and postural transitions. The activP AL is increasingly being used within field-based research for its ability to measure sitting/lying via posture. We summarise key issues to consider when using the activP AL in physical activity and sedentary behavior field-based research with adult populations. It is intended that the findings and discussion points be informative for researchers who are currently using activP AL monitors or are intending to use them. Pre-data collection decisions, monitor preparation and distribution, data collection considerations, and manual and automated data processing possibilities are presented using examples from current literature and experiences from 2 research groups from the UK and Australia. 展开更多
关键词 populations monitor lying collection accelerometer expenditure Australia stepping currently intended
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Dynamic Visualization Approach of the Multiphase Flow Using Electrical Capacitance Tomography 被引量:1
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作者 王泽璞 陈琪 +2 位作者 王雪瑶 李志宏 韩振兴 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2012年第2期380-388,共9页
Identifying the flow patterns is vital for understanding the complicated physical mechanisms in multiphase flows.For this purpose,electrical capacitance tomography(ECT) technique is considered as a promising visualiza... Identifying the flow patterns is vital for understanding the complicated physical mechanisms in multiphase flows.For this purpose,electrical capacitance tomography(ECT) technique is considered as a promising visualization method for the flow pattern identification,in which image reconstruction algorithms play an important role.In this paper,a generalized dynamic reconstruction model,which integrates ECT measurement information and physical evolution information of the objects of interest,was presented.A generalized objective functional that simultaneously considers the spatial constraints,temporal constraints and dynamic evolution information of the objects of interest was proposed.Numerical simulations and experiments were implemented to evaluate the feasibility and efficiency of the proposed algorithm.For the cases considered in this paper,the proposed algorithm can well reconstruct the flow patterns,and the quality of the reconstructed images is improved,which indicates that the proposed algorithm is competent to reconstruct the flow patterns in the visualization of multiphase flows. 展开更多
关键词 electrical capacitance tomography VISUALIZATION flow pattern identification dynamic reconstruction algorithm
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UGC-Driven Social Influence Study in Online Micro- Blogging Sites
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作者 LI Hui SHEN Bingqing +1 位作者 CUI Jiangtao MA Jianfeng 《China Communications》 SCIE CSCD 2014年第12期141-151,共11页
In Web 2.0 era,the content on a web page is increasingly generated by end users,rather than limited number of administrators.Hence,large number of User Generated Content(UGC) has driven the explosion of content in the... In Web 2.0 era,the content on a web page is increasingly generated by end users,rather than limited number of administrators.Hence,large number of User Generated Content(UGC) has driven the explosion of content in the web.Thanks to UGC,the pattern of web usage has evolved from download dominated way to a hybrid one with both information download and upload.Large number of UGC has unveiled great capacity of information that is unavailable for researchers before,such as individual preferences,social connections,and etc.In this paper,we propose a novel model which studies the UGC in micro-blogging web sites,the largest and fastest information diffusion media online,and evaluate the social influence for an arbitrary individual.Experimental results show that our model outperforms state-of-the-art techniques in social influence evaluation in both the running time and accuracy. 展开更多
关键词 user generated content microblog social influence communications
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A simple method to extract glacier length based on Digital Elevation Model and glacier boundaries for simple basin type glacier 被引量:3
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作者 JI Qin YANG Tai-bao +3 位作者 HE Yi QIN Yan DONG Jun HU Fan-sheng 《Journal of Mountain Science》 SCIE CSCD 2017年第9期1776-1790,共15页
Glacier length is a key morphological element that has many glaciological applications; however, it is often difficult to determine, especially for glaciers that cover larger spatial areas or those that exhibit freque... Glacier length is a key morphological element that has many glaciological applications; however, it is often difficult to determine, especially for glaciers that cover larger spatial areas or those that exhibit frequent temporal change. In this paper, we describe a new Arc GIS-based method that can derive glacier flow lines for determining glacier length based on digital elevation model and glacier outlines. This method involves(1) extraction of the highest and lowest points on a glacier,(2) calculation of 10-m contour lines on the glacier from 10 m to 100 m height, and(3) connection of the midpoints of each contour line with the highest and the lowest points in order to create a flow line, which is subsequently smoothed. In order to assess the reliability of this method, we tested the algorithm's results against flow lines calculated using field measurements, analysing data from the Chinese Glacier Inventory, and manual interpretation. These data showed that the new automated method is effective in deriving glacier flow lines when contour lines are relatively large; in particular, when they are between 70 m and 100 m. Nonetheless, a key limitation of the algorithm is the requirement to automatically delete repeated and closed curves in the pre-treatment processes. In addition to calculating glacier flow lines for derivation of glacier length, this method also can be used to effectively determine glacier terminus change. 展开更多
关键词 Glacier length Flow lines Glacier boundary DEM Arc GIS
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一种基于机器视觉的农田害虫活体动态图像特征获取系统
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作者 宋琨珷 徐峰 《电子质量》 2017年第12期72-76,共5页
农田害虫监测技术是实现适时、适量施药的重要前提,该技术为增加农业生产提供了重要保证。针对现有农田监测手段中运用较多的人工统计死体害虫造成的高成本、低准确性问题,该文提出一种低成本、高准确性的农田害虫活体动态特征获取系统... 农田害虫监测技术是实现适时、适量施药的重要前提,该技术为增加农业生产提供了重要保证。针对现有农田监测手段中运用较多的人工统计死体害虫造成的高成本、低准确性问题,该文提出一种低成本、高准确性的农田害虫活体动态特征获取系统。首先,使用间隔灯光采样法获取害虫原始图像并通过图像颜色特征和阈值法分割害虫与背景图像。然后,通过高斯滤波获得害虫的形状特征和数量信息。最后,通过帧间差分法获得害虫运动量信息。在不接触害虫的情况下完成虫情监测,减少传统监测中因害虫死体破损造成的统计误差,提高系统准确性。该系统可以为植保人员提供害虫运动的定量信息并预防大规模农作物病虫害的出现。 展开更多
关键词 目标轮廓检测 动量信息获取 活体害虫识别
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Contemporary Marxism and Post-industrial Economy
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作者 Victoria S. Gritsenko 《Journal of Philosophy Study》 2014年第3期195-199,共5页
Karl Marx (1973) scientifically predicted the appearance of some extraordinary tendencies of social development in the second half of the 20th century was given a common name of post-industrial or informational soci... Karl Marx (1973) scientifically predicted the appearance of some extraordinary tendencies of social development in the second half of the 20th century was given a common name of post-industrial or informational society and interpreted as post-bourgeois, post-capitalist, post-business society, and late capitalism. Autonomist Marxism and Perm philosophy school had separately come to a conclusion that all the phenomena noticed by the post-industrial theory could be adequately explained if we consider the historically new form of material labour appearing now. Marx (1973), who predicted this new form, named it automated, scientific, or universal labour. With the appearance of the universal labour, the wealth of the society depends on the universal human powers that help to involve the extensive powers of nature into the production process. Universal labour can not be averaged or measured by the labour time as the abstract labour; it implies high complexity and creativity. Involving increasingly powerful forces of nature and human society, it appears to be the labour of another essence and by its essence, it does not create value. 展开更多
关键词 modem Marxism universal labour destruction of value post-industrial society information
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Evaluation of Skills in Swing Technique in Classical Japanese Swordsmanship in laido Using Sensors
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作者 Satoru Okamoto Satomi Adachi 《Journal of Mechanics Engineering and Automation》 2016年第4期190-196,共7页
In this study, we analyzed the swing motions of more experienced practitioner and new practitioner of iaido players by using tri-axial acceleration sensor and gyro sensor. Iaido is a modern Japanese martial art/sport.... In this study, we analyzed the swing motions of more experienced practitioner and new practitioner of iaido players by using tri-axial acceleration sensor and gyro sensor. Iaido is a modern Japanese martial art/sport. In this way, the acceleration and gyro sensor measurement enabled detailed motion information at the installation points to be displayed in a short time, thus making it possible to easily extract the objective problems. Although it was not possible to confirm by the acceleration and angular velocity measurements the detailed motion of the entire body as obtained in the 2D motion analysis with a high-speed camera, it was confirmed that the acceleration and gyro sensor is an evaluation means that can be installed easily and can provide the exercise information in a short time as an objective index. 展开更多
关键词 Skill science classical Japanese swordsmanship in iaido acceleration sensor high-speed video camera gyro sensor.
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Research of the Thermal Parameters and the Accuracy of Flow Measurement of the Biological Fuel
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作者 Igor Korobiichuk Shavursky Yurij +1 位作者 Michal Nowicki Roman Szewczyk 《Journal of Mechanics Engineering and Automation》 2015年第7期415-419,共5页
The heat parameters, the thermoanemometric flow-meter (TAF) errors and the experimental characteristics have been defined. The results of experiments were conducted with the help of physically-informational models a... The heat parameters, the thermoanemometric flow-meter (TAF) errors and the experimental characteristics have been defined. The results of experiments were conducted with the help of physically-informational models allowing to realize all major thermal methods and their inherent informative options. The metrological evaluation was made and the sensitivity to the consumption of gas and liquid have been defined, their static and dynamic errors, followed by the comparison of costs according to these criteria. The developed method provides accurate measurement of volumetric flow of motor fuel 1.0-1.5% at heater temperature measurement accuracy of 1%. 展开更多
关键词 Thermoanemometric flow-meter biological fuel physically-informational models
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Side information refinement in distributed video coding
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作者 刘鸿彬 Zhao Debin +1 位作者 Ma Siwei Gao Wen 《High Technology Letters》 EI CAS 2012年第4期423-427,共5页
Side information (SI) is one of the key issues in distributed video coding (DVC) and affects the compression performance of DVC largely. This paper proposes an SI refinement algorithm, in which the Wyner-Ziv (WZ... Side information (SI) is one of the key issues in distributed video coding (DVC) and affects the compression performance of DVC largely. This paper proposes an SI refinement algorithm, in which the Wyner-Ziv (WZ) frame is split into two parts based on checkerboard pattern, and the two parts are encoded independently but decoded sequentially. In the decoding process, the part 1 is first decoded with the initial SI and partially decoded part (PDP) 1 is used to improve the motion vectors (MVs) and SI of both parts. At the next stage, the part 2 is decoded with the improved SI and PDP 2 is used to further refine MVs of the part 2. Then, SI of both parts are further refined. Simulation results show that the proposed algorithm can improve the peak signal to noise ratio (PSNR) by up to 1.43 dB when compared with traditional DVC codec. 展开更多
关键词 distributed video coding (DVC) side information (SI) checkerboard pattern
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Entropy, Fisher Information and Variance with Frost-Musulin Potenial 被引量:1
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作者 J.O.A.Idiodi C.A.Onate 《Communications in Theoretical Physics》 SCIE CAS CSCD 2016年第9期269-274,共6页
This study presents the Shannon and Renyi information entropy for both position and momentum space and the Fisher information for the position-dependent mass Schr¨odinger equation with the Frost-Musulin potential... This study presents the Shannon and Renyi information entropy for both position and momentum space and the Fisher information for the position-dependent mass Schr¨odinger equation with the Frost-Musulin potential. The analysis of the quantum mechanical probability has been obtained via the Fisher information. The variance information of this potential is equally computed. This controls both the chemical properties and physical properties of some of the molecular systems. We have observed the behaviour of the Shannon entropy. Renyi entropy, Fisher information and variance with the quantum number n respectively. 展开更多
关键词 Fisher information Shannon entropy position-dependent mass
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Generation of a genuine six-partite entangled state in trapped-ion system 被引量:1
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作者 DENG HongGui ZHENG XiaoJuan 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2012年第8期1427-1430,共4页
Recently, a genuine six-qubit entangled state Isix) has been proposed [Chen P X, et al. Phys Rev A, 2006, 74: 032324]. This state does not belong to the well-known three types of multipartite entangled states, i.e.,... Recently, a genuine six-qubit entangled state Isix) has been proposed [Chen P X, et al. Phys Rev A, 2006, 74: 032324]. This state does not belong to the well-known three types of multipartite entangled states, i.e., Greenberger-Home-Zeilinger (GHZ) state, W state, and linear cluster state. This state has many potential applications in quantum information processing. We pro- pose a scheme for generating such a genuine six-qubit entangled state for trapped ions in thermal motion. The scheme is insen- sitive to both the initial motional state and heating. 展开更多
关键词 six-qubit:trapped ion six-qubit:entangled state
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Efficient nonlocal two-step entanglement concentration protocol for three-level atoms in an arbitrary less-entangled W state using cavity input-output process 被引量:3
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作者 ZHANG Ru ZHOU SuHua CAO Cong 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2014年第8期1511-1518,共8页
We present an efficient two-step entanglement concentration protocol(ECP)for three-level atoms trapped in one-sided optical micro-cavities in an arbitrary three-particle less-entangled W state,using the coherent state... We present an efficient two-step entanglement concentration protocol(ECP)for three-level atoms trapped in one-sided optical micro-cavities in an arbitrary three-particle less-entangled W state,using the coherent state input-output process in low-Q cavity quantum electrodynamics system.In each step of the new proposed protocol,one of the three remote users prepares the auxiliary coherent optical pulses to perform cavity input-output process and then utilizes the standard homodyne measurement to discriminate the final outgoing coherent states.When both of the two steps are successful,remote parties can deterministically concentrate the less-entangled W state atoms to a standard maximally entangled W state.Compared with previous ECPs for W state,this protocol has some advantages and can be widely used in current quantum repeater and some quantum information processing tasks. 展开更多
关键词 entanglement concentration protocol W state cavity input-output process
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Energy budget of the magnetosphere-ionosphere system in solar Cycle 23 被引量:3
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作者 XU WenYao DU AiMin 《Science China(Technological Sciences)》 SCIE EI CAS 2012年第5期1184-1188,共5页
The energy budget of the magnetosphere-ionosphere (MI) system during 1998-2008 was examined by using Akasofu's epsilon function. The results showed that 1) the yearly average rate of solar wind energy input into t... The energy budget of the magnetosphere-ionosphere (MI) system during 1998-2008 was examined by using Akasofu's epsilon function. The results showed that 1) the yearly average rate of solar wind energy input into the MI system was 4.51 GGJ (GGJ=1018 J), while the yearly average total dissipation was 4.30 GGJ; 2) the energy partitioning in the ring current and polar region was 56%:44%; 3) the energy input and dissipation processes continuously proceeded both in storm-substorm events and less disturbed intervals, suggesting the significant contribution of slow but long-lasting energy process during the less disturbance periods to the total energy budget. In addition, we found in this study an interesting phenomenon "self-adjustment ability" of the MI system which behaves just like a water reservoir. During solar active years, the input energy is more than the dissipated energy, implying that a portion of the input energy is not immediately released, but is stored in the magnetosphere. On the other hand, during less active years, the dissipated energy is more than the input energy, implying that the previously stored energy makes up for the energy input shortage in this period. 展开更多
关键词 solar wind-magnetosphere coupling coupling function MAGNETOTAIL energy budget
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Dynamic and steady control of quantum coherence in photonic crystals via the Zeeman effect 被引量:2
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作者 CHEN LuZhou HUANG YongGang +1 位作者 JIN ChongJun WANG XueHua 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2012年第12期2300-2304,共5页
The dynamic evolution of a multi-level atom in the three-dimensional photonic crystal under an applied magnetic field is investigated.By combining the Zeeman effect with the photonic band gap effect,the dynamic quantu... The dynamic evolution of a multi-level atom in the three-dimensional photonic crystal under an applied magnetic field is investigated.By combining the Zeeman effect with the photonic band gap effect,the dynamic quantum superposition states and steady quantum coherent trapping states of the atom can be flexibly controlled.This paves the way for coherent manipulation of quantum states in the solid-state system,which has important applications in quantum information processing. 展开更多
关键词 quantum superposition state control of quantum coherence photonic crystal gap Zeeman effect
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Quantum Fisher Information of Driven Multi-particle Systems in Structured Bosonic Reservoirs
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作者 严凯 谢燕青 +1 位作者 黄雨梦 郝翔 《Communications in Theoretical Physics》 SCIE CAS CSCD 2017年第3期261-266,共6页
We investigate the dynamics of the precision of the parameter estimation in many driven atoms, each of which interacts with a local structured bosonic reservoir respectively. The evolution of quantum states for single... We investigate the dynamics of the precision of the parameter estimation in many driven atoms, each of which interacts with a local structured bosonic reservoir respectively. The evolution of quantum states for single driven atom is described by the time local quantum master equation. The dynamics of the quantum Fisher information for many entangled atoms is obtained by means of the supreoperator mapping. The estimation limit is superior to the standard quantum limit during a characteristic interval. At a given time, the precision of parameter estimation can be improved to a maximal value if the number of entangled atoms is chosen to be an optimal value. The optimal number of entangled atoms is determined by the dynamical property. The decay of quantum Fisher information is accelerated with the increase of the number of entangled atoms. 展开更多
关键词 quantum Fisher information parameter estimation quantum entanglement bosonic reservoir
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Non-Markovianity Measure Based on Brukner–Zeilinger Invariant Information for Unital Quantum Dynamical Maps
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作者 贺志 朱烈强 李莉 《Communications in Theoretical Physics》 SCIE CAS CSCD 2017年第3期255-260,共6页
A non-Markovianity measure based on Brukner–Zeilinger invariant information to characterize nonMarkovian effect of open systems undergoing unital dynamical maps is proposed. The method takes advantage of non-increasi... A non-Markovianity measure based on Brukner–Zeilinger invariant information to characterize nonMarkovian effect of open systems undergoing unital dynamical maps is proposed. The method takes advantage of non-increasing property of the Brukner–Zeilinger invariant information under completely positive and trace-preserving unital maps. The simplicity of computing the Brukner–Zeilinger invariant information is the advantage of the proposed measure because of mainly depending on the purity of quantum state. The measure effectively captures the characteristics of non-Markovianity of unital dynamical maps. As some concrete application, we consider two typical non-Markovian noise channels, i.e., the phase damping channel and the random unitary channel to show the sensitivity of the proposed measure. By investigation, we find that the conditions of detecting the non-Markovianity for the phase damping channel are consistent with the results of existing measures for non-Markovianity, i.e., information flow, divisibility and quantum mutual information. However, for the random unitary channel non-Markovian conditions are same to that of the information flow, but is different from that of the divisibility and quantum mutual information. 展开更多
关键词 non-Markovianity measure Brukner-Zeilinger invariant information unital maps
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Dynamical Change of Quantum Fisher Information of Cavity-Reservoir Systems
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作者 黄江 谢钦 《Communications in Theoretical Physics》 SCIE CAS CSCD 2016年第4期453-459,共7页
We study the quantum Fisher information(QFI) dynamics of the phase parameter in the enlarged cavityreservoir systems at zero temperature under two situations of large N limit and non-Markovian environment,respectively... We study the quantum Fisher information(QFI) dynamics of the phase parameter in the enlarged cavityreservoir systems at zero temperature under two situations of large N limit and non-Markovian environment,respectively.We find an important relation that the total quantities of QFI of the cavity and reservoir are equal to unit during the dynamical evolution.The lost QFI of the cavity transfers to its corresponding reservoir with the same quantities simultaneously.Moreover,we also find that the detuning parameter and non-Markovian effect are two significant factors to affect the preservation of QFI. 展开更多
关键词 dynamical change quantum Fisher information cavity-reservoir systems
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Strong Analog Classical Simulation of Coherent Quantum Dynamics
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作者 Dong-Sheng Wang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2017年第2期171-181,共11页
A strong analog classical simulation of general quantum evolution is proposed, which serves as a novel scheme in quantum computation and simulation. The scheme employs the approach of geometric quantum mechanics and q... A strong analog classical simulation of general quantum evolution is proposed, which serves as a novel scheme in quantum computation and simulation. The scheme employs the approach of geometric quantum mechanics and quantum informational technique of quantum tomography, which applies broadly to cases of mixed states, nonunitary evolution, and infinite dimensional systems. The simulation provides an intriguing classical picture to probe quantum phenomena, namely, a coherent quantum dynamics can be viewed as a globally constrained classical Hamiltonian dynamics of a collection of coupled particles or strings. Efficiency analysis reveals a fundamental difference between the locality in real space and locality in Hilbert space, the latter enables efficient strong analog classical simulations. Examples are also studied to highlight the differences and gaps among various simulation methods. 展开更多
关键词 quantum simulation geometric quantum mechanics phase space
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