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BER performance analysis of non-Hermitian symmetry OFDM-VLC systems with ADC quantization noise
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作者 WANG Zhongpeng AI Caihua ZHANG Lijuan 《Optoelectronics Letters》 2025年第11期677-683,共7页
Quantization noise caused by analog-to-digital converter(ADC)gives rise to the reliability performance degradation of communication systems.In this paper,a quantized non-Hermitian symmetry(NHS)orthogonal frequency-div... Quantization noise caused by analog-to-digital converter(ADC)gives rise to the reliability performance degradation of communication systems.In this paper,a quantized non-Hermitian symmetry(NHS)orthogonal frequency-division multiplexing-based visible light communication(OFDM-VLC)system is presented.In order to analyze the effect of the resolution of ADC on NHS OFDM-VLC,a quantized mathematical model of NHS OFDM-VLC is established.Based on the proposed quantized model,a closed-form bit error rate(BER)expression is derived.The theoretical analysis and simulation results both confirm the effectiveness of the obtained BER formula in high-resolution ADC.In addition,channel coding is helpful in compensating for the BER performance loss due to the utilization of lower resolution ADC. 展开更多
关键词 quantized modela communication systemsin Bit Error Rate quantized mathematical model reliability performance degradation non hermitian symmetry ADC quantization OFDM VLC
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Optimizing BERT for Bengali Emotion Classification: Evaluating Knowledge Distillation, Pruning, and Quantization
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作者 Md Hasibur Rahman Mohammed Arif Uddin +1 位作者 Zinnat Fowzia Ria Rashedur M.Rahman 《Computer Modeling in Engineering & Sciences》 2025年第2期1637-1666,共30页
The rapid growth of digital data necessitates advanced natural language processing(NLP)models like BERT(Bidi-rectional Encoder Representations from Transformers),known for its superior performance in text classificati... The rapid growth of digital data necessitates advanced natural language processing(NLP)models like BERT(Bidi-rectional Encoder Representations from Transformers),known for its superior performance in text classification.However,BERT’s size and computational demands limit its practicality,especially in resource-constrained settings.This research compresses the BERT base model for Bengali emotion classification through knowledge distillation(KD),pruning,and quantization techniques.Despite Bengali being the sixth most spoken language globally,NLP research in this area is limited.Our approach addresses this gap by creating an efficient BERT-based model for Bengali text.We have explored 20 combinations for KD,quantization,and pruning,resulting in improved speedup,fewer parameters,and reduced memory size.Our best results demonstrate significant improvements in both speed and efficiency.For instance,in the case of mBERT,we achieved a 3.87×speedup and 4×compression ratio with a combination of Distil+Prune+Quant that reduced parameters from 178 to 46 M,while the memory size decreased from 711 to 178 MB.These results offer scalable solutions for NLP tasks in various languages and advance the field of model compression,making these models suitable for real-world applications in resource-limited environments. 展开更多
关键词 Bengali NLP black-box distillation emotion classification model compression post-training quantization unstructured pruning
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Automatic diagnosis of keratitis from low-quality slit-lamp images using feature vector quantization and self-attention mechanisms
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作者 JIANG Jiewei XIN Yu +3 位作者 DING Ke ZHU Mingmin CHEN Yi LI Zhongwen 《Optoelectronics Letters》 2025年第10期612-618,共7页
This paper proposes a novel method for the automatic diagnosis of keratitis using feature vector quantization and self-attention mechanisms(ADK_FVQSAM).First,high-level features are extracted using the DenseNet121 bac... This paper proposes a novel method for the automatic diagnosis of keratitis using feature vector quantization and self-attention mechanisms(ADK_FVQSAM).First,high-level features are extracted using the DenseNet121 backbone network,followed by adaptive average pooling to scale the features to a fixed length.Subsequently,product quantization with residuals(PQR)is applied to convert continuous feature vectors into discrete features representations,preserving essential information insensitive to image quality variations.The quantized and original features are concatenated and fed into a self-attention mechanism to capture keratitis-related features.Finally,these enhanced features are classified through a fully connected layer.Experiments on clinical low-quality(LQ)images show that ADK_FVQSAM achieves accuracies of 87.7%,81.9%,and 89.3% for keratitis,other corneal abnormalities,and normal corneas,respectively.Compared to DenseNet121,Swin transformer,and InceptionResNet,ADK_FVQSAM improves average accuracy by 3.1%,11.3%,and 15.3%,respectively.These results demonstrate that ADK_FVQSAM significantly enhances the recognition performance of keratitis based on LQ slit-lamp images,offering a practical approach for clinical application. 展开更多
关键词 KERATITIS low quality images adaptive average pooling densenet backbone networkfollowed self attention mechanism feature vector quantization diagnosis keratitis automatic diagnosis
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High-Efficiency Video Coder in Pruned Environment Using Adaptive Quantization Parameter Selection
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作者 Krishan Kumar Mohamed Abouhawwash +2 位作者 Amit Kant Pandit Shubham Mahajan Mofreh A.Hogo 《Computers, Materials & Continua》 SCIE EI 2022年第10期1977-1993,共17页
The high-efficiency video coder(HEVC)is one of the most advanced techniques used in growing real-time multimedia applications today.However,they require large bandwidth for transmission through bandwidth,and bandwidth... The high-efficiency video coder(HEVC)is one of the most advanced techniques used in growing real-time multimedia applications today.However,they require large bandwidth for transmission through bandwidth,and bandwidth varies with different video sequences/formats.This paper proposes an adaptive information-based variable quantization matrix(AIVQM)developed for different video formats having variable energy levels.The quantization method is adapted based on video sequence using statistical analysis,improving bit budget,quality and complexity reduction.Further,to have precise control over bit rate and quality,a multi-constraint prune algorithm is proposed in the second stage of the AI-VQM technique for pre-calculating K numbers of paths.The same should be handy to selfadapt and choose one of the K-path automatically in dynamically changing bandwidth availability as per requirement after extensive testing of the proposed algorithm in the multi-constraint environment for multiple paths and evaluating the performance based on peak signal to noise ratio(PSNR),bit-budget and time complexity for different videos a noticeable improvement in rate-distortion(RD)performance is achieved.Using the proposed AIVQM technique,more feasible and efficient video sequences are achieved with less loss in PSNR than the variable quantization method(VQM)algorithm with approximately a rise of 10%–20%based on different video sequences/formats. 展开更多
关键词 Adaptive quantization high-efficient video coding(HEVC) quad-tree rate-distortion optimization(RDO) video compression variable quantization method(VQM) quantization parameter(QP)
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An Efficient Information Hiding Scheme Based on Closest Paired Tree Structure Vector Quantization 被引量:1
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作者 Zhi-Hui Wang Chin-Chen Chang Ting-Yu Lin 《Journal of Electronic Science and Technology》 CAS 2013年第1期15-19,共5页
Information hiding schemes based on vector quantization (VQ) usually require lengthy VQ encoding and decoding processes. In this paper, we propose an efficient information hiding method based on closest paired tree ... Information hiding schemes based on vector quantization (VQ) usually require lengthy VQ encoding and decoding processes. In this paper, we propose an efficient information hiding method based on closest paired tree structure vector quantization (CPTSVQ). The simulation result shows that the execution time of the proposed scheme is much shorter than that attained by previous approaches. 展开更多
关键词 Digital image information hiding tree structure vector quantization vector quantization.
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Lattice Vector Quantization Applied to Speech and Audio Coding 被引量:1
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作者 Minjie Xie 《ZTE Communications》 2012年第2期25-33,共9页
Lattice vector quantization (LVQ) has been used for real-time speech and audio coding systems. Compared with conventional vector quantization, LVQ has two main advantages: It has a simple and fast encoding process,... Lattice vector quantization (LVQ) has been used for real-time speech and audio coding systems. Compared with conventional vector quantization, LVQ has two main advantages: It has a simple and fast encoding process, and it significantly reduces the amount of memory required. Therefore, LVQ is suitable for use in low-complexity speech and audio coding. In this paper, we describe the basic concepts of LVQ and its advantages over conventional vector quantization. We also describe some LVQ techniques that have been used in speech and audio coding standards of international standards developing organizations (SDOs). 展开更多
关键词 Vector quantization lattice vector quantization speech and audio coding transform coding
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Using a Toy Model to Improve the Quantization of Gravity and Field Theories 被引量:1
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作者 John R. Klauder 《Journal of High Energy Physics, Gravitation and Cosmology》 2022年第2期303-308,共6页
A half-harmonic oscillator, which gets its name because the position coordinate is strictly positive, has been quantized and determined that it was a physically correct quantization. This positive result was found usi... A half-harmonic oscillator, which gets its name because the position coordinate is strictly positive, has been quantized and determined that it was a physically correct quantization. This positive result was found using affine quantization (AQ). The main purpose of this paper is to compare results of this new quantization procedure with those of canonical quantization (CQ). Using Ashtekar-like classical variables and CQ, we quantize the same toy model. While these two quantizations lead to different results, they both would reduce to the same classical Hamiltonian if &hstrok;→ 0. Since these two quantizations have differing results, only one of the quantizations can be physically correct. Two brief sections also illustrate how AQ can correctly help quantum gravity and the quantization of most field theory problems. 展开更多
关键词 Toy Model Affine quantization (AQ) Canonical quantization (CQ)
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A Simple Factor in Canonical Quantization Yields Affine Quantization Even for Quantum Gravity 被引量:1
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作者 John R. Klauder 《Journal of High Energy Physics, Gravitation and Cosmology》 2021年第4期1328-1332,共5页
Canonical quantization (CQ) is built around [<i>Q</i>, <i>P</i>] = <i>i&hstrok;</i>1l , while affine quantization (AQ) is built around [<i>Q</i>,<i>D</i>... Canonical quantization (CQ) is built around [<i>Q</i>, <i>P</i>] = <i>i&hstrok;</i>1l , while affine quantization (AQ) is built around [<i>Q</i>,<i>D</i>] = <i>i&hstrok;Q</i>, where <i>D</i> ≡ (<i>PQ</i> +<i>QP</i>) / 2 . The basic CQ operators must fit -∞ < <i>P</i>, <i>Q</i> < ∞ , while the basic AQ operators can fit -∞ < <i>P</i> < ∞ and 0 < <i>Q</i> < ∞ , -∞ < <i>Q</i> < 0 , or even -∞ < <i>Q</i> ≠ 0 < ∞ . AQ can also be the key to quantum gravity, as our simple outline demonstrates. 展开更多
关键词 Canonical quantization (CQ) Affine quantization (AQ) Quantum Gravity
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Improved Canonical Quantization Method of Self Dual Field
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作者 樊丰华 黄永畅 《Communications in Theoretical Physics》 SCIE CAS CSCD 2012年第10期504-508,共5页
In this paper,the improved canonical quantization method of the self dual field is given in order to overcome linear combination problem about the second class constraint and the first class constraint number maximiza... In this paper,the improved canonical quantization method of the self dual field is given in order to overcome linear combination problem about the second class constraint and the first class constraint number maximization problem in the Dirac method.In the improved canonical quantization method,there are no artificial linear combination and the first class constraint number maximization problems,at the same time,the stability of the system is considered.Therefore,the improved canonical quantization method is more natural and easier accepted by people than the usual Dirac method.We use the improved canonical quantization method to realize the canonical quantization of the self dual field,which has relation with string theory successfully and the results are equal to the results by using the Dirac method. 展开更多
关键词 canonical quantization self dual field canonical quantization method
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Reinforcement Learning Based Quantization Strategy Optimal Assignment Algorithm for Mixed Precision
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作者 Yuejiao Wang Zhong Ma +2 位作者 Chaojie Yang Yu Yang Lu Wei 《Computers, Materials & Continua》 SCIE EI 2024年第4期819-836,共18页
The quantization algorithm compresses the original network by reducing the numerical bit width of the model,which improves the computation speed. Because different layers have different redundancy and sensitivity to d... The quantization algorithm compresses the original network by reducing the numerical bit width of the model,which improves the computation speed. Because different layers have different redundancy and sensitivity to databit width. Reducing the data bit width will result in a loss of accuracy. Therefore, it is difficult to determinethe optimal bit width for different parts of the network with guaranteed accuracy. Mixed precision quantizationcan effectively reduce the amount of computation while keeping the model accuracy basically unchanged. In thispaper, a hardware-aware mixed precision quantization strategy optimal assignment algorithm adapted to low bitwidth is proposed, and reinforcement learning is used to automatically predict the mixed precision that meets theconstraints of hardware resources. In the state-space design, the standard deviation of weights is used to measurethe distribution difference of data, the execution speed feedback of simulated neural network accelerator inferenceis used as the environment to limit the action space of the agent, and the accuracy of the quantization model afterretraining is used as the reward function to guide the agent to carry out deep reinforcement learning training. Theexperimental results show that the proposed method obtains a suitable model layer-by-layer quantization strategyunder the condition that the computational resources are satisfied, and themodel accuracy is effectively improved.The proposed method has strong intelligence and certain universality and has strong application potential in thefield of mixed precision quantization and embedded neural network model deployment. 展开更多
关键词 Mixed precision quantization quantization strategy optimal assignment reinforcement learning neural network model deployment
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Solving Major Problems Using Vector Affine Quantization
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作者 John R. Klauder 《Journal of High Energy Physics, Gravitation and Cosmology》 2022年第1期178-183,共6页
Affine quantization is a parallel procedure to canonical quantization, which is ideally suited to deal with special problems. Vector affine quantization introduces multiple degrees of freedom which find that working t... Affine quantization is a parallel procedure to canonical quantization, which is ideally suited to deal with special problems. Vector affine quantization introduces multiple degrees of freedom which find that working together creates novel tools suitable to eliminate typical difficulties encountered in more conventional approaches. 展开更多
关键词 AFFINE quantization Vector Field Models Canonical quantization
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A hybrid quantum encoding algorithm of vector quantization for image compression 被引量:4
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作者 庞朝阳 周正威 郭光灿 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第12期3039-3043,共5页
Many classical encoding algorithms of vector quantization (VQ) of image compression that can obtain global optimal solution have computational complexity O(N). A pure quantum VQ encoding algorithm with probability... Many classical encoding algorithms of vector quantization (VQ) of image compression that can obtain global optimal solution have computational complexity O(N). A pure quantum VQ encoding algorithm with probability of success near 100% has been proposed, that performs operations 45√N times approximately. In this paper, a hybrid quantum VQ encoding algorithm between the classical method and the quantum algorithm is presented. The number of its operations is less than √N for most images, and it is more efficient than the pure quantum algorithm. 展开更多
关键词 vector quantization Grover's algorithm image compression quantum algorithm
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Stabilization of Uncertain Systems With Markovian Modes of Time Delay and Quantization Density 被引量:4
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作者 Jufeng Wang Chunfeng Liu 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2018年第2期463-470,共8页
This work studies the stabilization of a class of control systems that use communication networks as signal transmission medium. The lateral motion of independently actuated four-wheel vehicle is modeled as an uncerta... This work studies the stabilization of a class of control systems that use communication networks as signal transmission medium. The lateral motion of independently actuated four-wheel vehicle is modeled as an uncertain-linear system. Time delay and quantization density are modeled as Markov chains.The networked control systems(NCSs) with plants being lateral motion are first transformed to switched linear systems with uncertain parameters. Sufficient and necessary conditions for the stochastic stability of closed-loop networked control systems are then established. By solving the matrix inequalities, this work presents an output-feedback controller that depends on the modes of time delay and quantization density. The controller performance is illustrated via a vehicular lateral motion system. 展开更多
关键词 Index Terms--Networked control system (NCS) quantization STABILIZATION time delay vehicle lateral motion.
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Quantization-Based Robust Image Watermarking Using the Dual Tree Complex Wavelet Transform 被引量:4
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作者 LIU Jinhua SHE Kun 《China Communications》 SCIE CSCD 2010年第4期1-6,共6页
Conventional quantization index modulation (QIM) watermarking uses the fixed quantization step size for the host signal.This scheme is not robust against geometric distortions and may lead to poor fidelity in some are... Conventional quantization index modulation (QIM) watermarking uses the fixed quantization step size for the host signal.This scheme is not robust against geometric distortions and may lead to poor fidelity in some areas of content.Thus,we proposed a quantization-based image watermarking in the dual tree complex wavelet domain.We took advantages of the dual tree complex wavelets (perfect reconstruction,approximate shift invariance,and directional selectivity).For the case of watermark detecting,the probability of false alarm and probability of false negative were exploited and verified by simulation.Experimental results demonstrate that the proposed method is robust against JPEG compression,additive white Gaussian noise (AWGN),and some kinds of geometric attacks such as scaling,rotation,etc. 展开更多
关键词 Image Watermarking quantization IndexModulation Dual Tree Complex Wavelet Transform JPEG Compression
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The Wave-Particle Duality—Does the Concept of Particle Make Sense in Quantum Mechanics? Should We Ask the Second Quantization? 被引量:4
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作者 Sofia D. Wechsler 《Journal of Quantum Information Science》 2019年第3期155-170,共16页
The quantum object is in general considered as displaying both wave and particle nature. By particle is understood an item localized in a very small volume of the space, and which cannot be simultaneously in two disjo... The quantum object is in general considered as displaying both wave and particle nature. By particle is understood an item localized in a very small volume of the space, and which cannot be simultaneously in two disjoint regions of the space. By wave, to the contrary, is understood a distributed item, occupying in some cases two or more disjoint regions of the space. The quantum formalism did not explain until today the so-called “collapse” of the wave-function, i.e. the shrinking of the wave-function to one small region of the space, when a macroscopic object is encountered. This seems to happen in “which-way” experiments. A very appealing explanation for this behavior is the idea of a particle, localized in some limited part of the wave-function. The present article challenges the concept of particle. It proves in the base of a variant of the Tan, Walls and Collett experiment, that this concept leads to a situation in which the particle has to be simultaneously in two places distant from one another—situation that contradicts the very definition of a particle. Another argument is based on a modified version of the Afshar experiment, showing that the concept of particle is problematic. The concept of particle makes additional difficulties when the wave-function passes through fields. An unexpected possibility to solve these difficulties seems to arise from the cavity quantum electrodynamics studies done recently by S. Savasta and his collaborators. It involves virtual particles. One of these studies is briefly described here. Though, experimental results are needed, so that it is too soon to conclude whether it speaks in favor, or against the concept of particle. 展开更多
关键词 Quantum Mechanics Wave-Particle DUALITY EMPTY Waves First quantization Second quantization
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Quantization of light energy directly from classical electromagnetic theory in vacuum 被引量:2
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作者 佘卫龙 《Chinese Physics B》 SCIE EI CAS CSCD 2005年第12期2514-2521,共8页
It is currently believed that light quantum or the quantization of light energy is beyond classical physics, and the picture of wave-particle duality, which was criticized by Einstein but has attracted a number of exp... It is currently believed that light quantum or the quantization of light energy is beyond classical physics, and the picture of wave-particle duality, which was criticized by Einstein but has attracted a number of experimental researches, is necessary for the description of light. It is shown in this paper, however, that the quantization of light energy in vacuum, which is the same as that in quantum electrodynamics, can be derived directly from the classical electromagnetic theory through the consideration of statistics based on classical physics. Therefore, the quantization of energy is an intrinsic property of light as a classical electromagnetic wave and has no need of being related to particles. 展开更多
关键词 the nature of light quantization of light energy classical electromagnetic theory consideration of statistics
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Rotational symmetry of classical orbits, arbitrary quantization of angular momentum and the role of the gauge field in two-dimensional space 被引量:2
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作者 辛俊丽 梁九卿 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第4期67-73,共7页
We study quantum classical correspondence in terms of the coherent wave functions of a charged particle in two-dimensional central-scalar potentials as well as the gauge field of a magnetic flux in the sense that the ... We study quantum classical correspondence in terms of the coherent wave functions of a charged particle in two-dimensional central-scalar potentials as well as the gauge field of a magnetic flux in the sense that the probability clouds of wave functions are well localized on classical orbits. For both closed and open classical orbits, the non-integer angular-momentum quantization with the level space of angular momentum being greater or less than h is determined uniquely by the same rotational symmetry of classical orbits and probability clouds of coherent wave functions, which is not necessarily 27r-periodic. The gauge potential of a magnetic flux impenetrable to the particle cannot change the quantization rule but is able to shift the spectrum of canonical angular momentum by a flux-dependent value, which results in a common topological phase for all wave functions in the given model. The well-known quantum mechanical anyon model becomes a special case of the arbitrary quantization, where the classical orbits are 2π-periodic. 展开更多
关键词 quantum-classical correspondence ANYON rotational symmetry arbitrary quantization of angular momentum
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Using Affine Quantization to Analyze Non-Renormalizable Scalar Fields and the Quantization of Einstein’s Gravity 被引量:11
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作者 John R. Klauder 《Journal of High Energy Physics, Gravitation and Cosmology》 2020年第4期802-816,共15页
Affine quantization is a parallel procedure to canonical quantization, which is ideally suited to deal with non-renormalizable scalar models as well as quantum gravity. The basic applications of this approach lead to ... Affine quantization is a parallel procedure to canonical quantization, which is ideally suited to deal with non-renormalizable scalar models as well as quantum gravity. The basic applications of this approach lead to the common goals of any quantization, such as Schroedinger’s representation and Schroedinger’s equation. Careful attention is paid toward seeking favored classical variables, which are those that should be promoted to the principal quantum operators. This effort leads toward classical variables that have a constant positive, zero, or negative curvature, which typically characterize such favored variables. This focus leans heavily toward affine variables with a constant negative curvature, which leads to a surprisingly accommodating analysis of non-renormalizable scalar models as well as Einstein’s general relativity. 展开更多
关键词 Favored Variables Affine quantization Non-Renormalizable Scalars General Relativity
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Establishing formal state space models via quantization forquantum control systems 被引量:2
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作者 DongDaoyi ChenZonghai 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2005年第2期398-402,共5页
Formal state space models of quantum control systems are deduced and a scheme to establish formal state space models via quantization could been obtained for quantum control systems is proposed. State evolution of qua... Formal state space models of quantum control systems are deduced and a scheme to establish formal state space models via quantization could been obtained for quantum control systems is proposed. State evolution of quantum control systems must accord with Schrdinger equations, so it is foremost to obtain Hamiltonian operators of systems. There are corresponding relations between operators of quantum systems and corresponding physical quantities of classical systems, such as momentum, energy and Hamiltonian, so Schrdinger equation models of corresponding quantum control systems via quantization could been obtained from classical control systems, and then establish formal state space models through the suitable transformation from Schrdinger equations for these quantum control systems. This method provides a new kind of path for modeling in quantum control. 展开更多
关键词 quantum control systems formal state space models quantization.
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s-parameterized Weyl transformation and the corresponding quantization scheme 被引量:2
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作者 王继锁 孟祥国 范洪义 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第1期265-268,共4页
By extending the usual Weyl transformation to the s-parameterized Weyl transformation with s being a real parameter,we obtain the s-parameterized quantization scheme which includes P–Q quantization, Q–P quantization... By extending the usual Weyl transformation to the s-parameterized Weyl transformation with s being a real parameter,we obtain the s-parameterized quantization scheme which includes P–Q quantization, Q–P quantization, and Weyl ordering as its three special cases. Some operator identities can be derived directly by virtue of the s-parameterized quantization scheme. 展开更多
关键词 generalized Wigner transformation s-parameterized quantization scheme
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