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Differential flatness-based distributed control of underactuated robot swarms 被引量:1
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作者 Ningbo AN Qishao WANG +1 位作者 Xiaochuan ZHAO Qingyun WANG 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2023年第10期1777-1790,共14页
This paper proposes a distributed control method based on the differential flatness(DF) property of robot swarms. The swarm DF mapping is established for underactuated differentially flat dynamics, according to the co... This paper proposes a distributed control method based on the differential flatness(DF) property of robot swarms. The swarm DF mapping is established for underactuated differentially flat dynamics, according to the control objective. The DF mapping refers to the fact that the system state and input of each robot can be derived algebraically from the flat outputs of the leaders and the cooperative errors and their finite order derivatives. Based on the proposed swarm DF mapping, a distributed controller is designed. The distributed implementation of swarm DF mapping is achieved through observer design. The effectiveness of the proposed method is validated through a numerical simulation of quadrotor swarm synchronization. 展开更多
关键词 differential flatness(DF) underactuated robot distributed control SYNCHRONIZATION
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A Method for Classification and Evaluation of Pilot’s Mental States Based on CNN
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作者 Qianlei Wang Zaijun Wang +2 位作者 Renhe Xiong Xingbin Liao Xiaojun Tan 《Computer Systems Science & Engineering》 SCIE EI 2023年第8期1999-2020,共22页
How to accurately recognize the mental state of pilots is a focus in civil aviation safety.The mental state of pilots is closely related to their cognitive ability in piloting.Whether the cognitive ability meets the s... How to accurately recognize the mental state of pilots is a focus in civil aviation safety.The mental state of pilots is closely related to their cognitive ability in piloting.Whether the cognitive ability meets the standard is related to flight safety.However,the pilot’s working state is unique,which increases the difficulty of analyzing the pilot’s mental state.In this work,we proposed a Convolutional Neural Network(CNN)that merges attention to classify the mental state of pilots through electroencephalography(EEG).Considering the individual differences in EEG,semi-supervised learning based on improvedK-Means is used in themodel training to improve the generalization ability of the model.We collected the EEG data of 12 pilot trainees during the simulated flight and compared the method in this paper with other methods on this data.The method in this paper achieved an accuracy of 86.29%,which is better than 4D-aNN and HCNN etc.Negative emotion will increase the probability of fatigue appearing,and emotion recognition is also meaningful during the flight.Then we conducted experiments on the public dataset SEED,and our method achieved an accuracy of 93.68%.In addition,we combine multiple parameters to evaluate the results of the classification network on a more detailed level and propose a corresponding scoring mechanism to display the mental state of the pilots directly. 展开更多
关键词 PILOT mental state EEG ATTENTION CNN semi-supervised learning
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CONSTITUTIVE EQUATION OF CO-ROTATIONAL DERIVATIVE TYPE FOR ANISOTROPIC-VISCOELASTIC FLUID 被引量:7
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作者 韩式方 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2004年第1期46-53,共8页
A constitutive equation theory of Oldroyd fluid B type,i.e.the co-rotational derivative type,is developed for the anisotropic-viscoelastic fluid of liquid crystalline(LC)polymer.Analyzing the influence of the orientat... A constitutive equation theory of Oldroyd fluid B type,i.e.the co-rotational derivative type,is developed for the anisotropic-viscoelastic fluid of liquid crystalline(LC)polymer.Analyzing the influence of the orientational motion on the material behavior and neglecting the influence,the constitutive equation is applied to a simple case for the hydrodynamic motion when the orientational contribution is neglected in it and the anisotropic relaxation,retardation times and anisotropic viscosi- ties are introduced to describe the macroscopic behavior of the anisotropic LC polymer fluid.Using the equation for the shear flow of LC polymer fluid,the analytical expressions of the apparent viscosity and the normal stress differences are given which are in a good agreement with the experimental results of Baek et al.For the fiber spinning flow of the fluid,the analytical expression of the extensional viscosity is given. 展开更多
关键词 constitutive equation anisotropic-viscoelastic fluid liquid crystalline polymer nonNewtonian flow co-rotational derivative anisotropic material functions shear flow extensional flow
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Research advances of un-symmetric constitutive theory of anisotropic viscoelastic liquids and its hydrodynamic behavior 被引量:1
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作者 韩式方 《Journal of Central South University》 SCIE EI CAS 2008年第S1期1-4,共4页
Research advances of un-symmetric constitutive equation of anisotropic fluid,influence of un-symmetric stress tensor on material functions,vibrational shear flow of the fluid with small amplitudes and rheology of anis... Research advances of un-symmetric constitutive equation of anisotropic fluid,influence of un-symmetric stress tensor on material functions,vibrational shear flow of the fluid with small amplitudes and rheology of anisotropic suspension were reported.A new concept of simple anisotropic fluid was introduced.On the basis of anisotropic principle,the simple fluid stress behaviour was described by velocity gradient tensor F and spin tensor W instead of velocity gradient tensor D in the classic Leslie-Ericksen continuum theory.Two relaxation times analyzing rheological nature of the fluid and using tensor analysis a general form of the constitutive equation of co-rotational type was introduced.More general model LCP-H for the fluid was developed.The unsymmetry of the shear stress was predicted by the present continuum theory for anisotropic viscoelastic fluid-LC polymer liquids.The influence of the relaxation times on material functions was specially studied.It is important to study the unsteady vibrational rotating flow with small amplitudes,as it is a best way to obtain knowledge of elasticity of the LC polymer,i.e.dynamic viscoelasticity.For the shear-unsymmetric stresses,two shear stresses were obtained thus two complex viscosities and two complex shear modulus(i.e.first and second one) were introduced by the constitutive equation which was defined by rotating shear rate introduced by author.For the two stability problems of fluid,such as stability of hydrodynamic flow and orientational motion,were discussed.The results show that the polymer suspension systems exhibit anisotropic character.The PNC systems can exhibit significant shear-thinning effects.For more concentrated polymer nano-suspensions,the first normal stress difference change from positive to negative,which is similar to LC polymer behavior. 展开更多
关键词 un-symmetric constitutive equation ANISOTROPIC fluid liquid crystalline POLYMER stability hydrodynamic FLOW orientational motion vibrational shear FLOW rheology of POLYMER suspension
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A Class of Parallel Algorithms of Real-TimeNumerical Simulation for Stiff Dynamic System 被引量:2
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作者 Cao Xuenian Liu Degui Li Shoufu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2000年第4期51-58,共8页
In this paper a class of real-time parallel modified Rosenbrock methods of numerical simulation is constructed for stiff dynamic systems on a multiprocessor system, and convergence and numerical stability of these met... In this paper a class of real-time parallel modified Rosenbrock methods of numerical simulation is constructed for stiff dynamic systems on a multiprocessor system, and convergence and numerical stability of these methods are discussed. A-stable real-time parallel formula of two-stage third-order and A(α)-stable real-time parallel formula with o ≈ 89.96° of three-stage fourth-order are particularly given. The numerical simulation experiments in parallel environment show that the class of algorithms is efficient and applicable, with greater speedup. 展开更多
关键词 Dynamic system Real-time simulation Parallel algorithms?
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Hydrodynamics Research on Amphibious Vehicle Systems:Engineering Application 被引量:1
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作者 居乃鵕 《Defence Technology(防务技术)》 SCIE EI CAS 2006年第2期87-95,共9页
Based on the modeling theoretical research of the amphibious vehicle systems, a simulation computed architecture on the state space expressions of hydrodynamics for amphibious vehicle systems are educed, and simulatio... Based on the modeling theoretical research of the amphibious vehicle systems, a simulation computed architecture on the state space expressions of hydrodynamics for amphibious vehicle systems are educed, and simulation computed results of navigation characteristics, vibration-impact characteristics, firing-hitting characteristics for amphibious vehicle on water are given. It is shown that the hydrodynamic research on amphibious vehicle systems is necessary and feasible. 展开更多
关键词 坦克 两栖车 动力方程 水力试验
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Vibrational shear flow of anisotropic viscoelastic fluid with small amplitudes
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作者 韩式方 《Journal of Central South University》 SCIE EI CAS 2008年第S1期29-32,共4页
Using the constitutive equation of co-rotational derivative type for anisotropic viscoelastic fluid-liquid crystalline(LC),polymer liquids was developed.Two relaxation times are introduced in the equation:λn represen... Using the constitutive equation of co-rotational derivative type for anisotropic viscoelastic fluid-liquid crystalline(LC),polymer liquids was developed.Two relaxation times are introduced in the equation:λn represents relaxation of the normal-symmetric stress components;λs represents relaxation of the shear-unsymmetric stress components.A vibrational rotating flow in gap between cylinders with small amplitudes is studied for the anisotropic viscoelastic fluid-liquid crystalline polymer.The time-dependent constitutive equation are linearized with respect to parameter of small amplitude.For the normal-symmetric part of stress tensor analytical expression of the shear stress is obtained by the constitutive equation.The complex viscosity,complex shear modulus,dynamic and imaginary viscosities,storage modulus and loss modulus are obtained for the normal-symmetric stress case which are defined by the common shear rate.For the shear-unsymmetric stress part,two shear stresses are obtained thus two complex viscosities and two complex shear modulus(i.e.first and second one) are given by the constitutive equation which are defined by rotating shear rate introduced by author.The dynamic and imaginary viscosities,storage modulus and loss modulus are given for each complex viscosities and complex shear modulus.Using the constituive equation the rotating flow with small amplitudes in gap between two coaxial cylinders is studied. 展开更多
关键词 un-symmetric CONSTITUTIVE equation ANISOTROPIC VISCOELASTIC fluid liquid CRYSTALLINE polymer VIBRATIONAL shear flow with small AMPLITUDES
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Construction of Domain Web Classification Ontology Based on Suggested Upper Merged Ontology
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作者 GAO Kening, ZHANG Yin ZHANG Bin MA Anxiang 《Wuhan University Journal of Natural Sciences》 CAS 2008年第4期435-439,共5页
Aiming at the problem of merging heterogeneous semantic taxonomy emerged in Web information integration, a method of building Web classification ontology (WCO) has been proposed. A WCO that is logically consistent w... Aiming at the problem of merging heterogeneous semantic taxonomy emerged in Web information integration, a method of building Web classification ontology (WCO) has been proposed. A WCO that is logically consistent with the suggested upper merged ontology (SUMO) is defined, together with axioms needed to classify Web pages. WCO can be used as a foundation of merging heterogeneous semantic taxonomy, and could be used to support Web information integration and classification based Web information retrieval. 展开更多
关键词 ONTOLOGY semantic heterogeneity Web classificationontology (WCO) suggested upper merged ontology (SUMO) REASONING
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Temperature Drift Modeling of FOG Based on LS-WSVM
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作者 王立平 孔小梅 +3 位作者 付梦印 王美玲 张甲文 姜明 《Defence Technology(防务技术)》 SCIE EI CAS 2008年第3期188-190,共3页
Large temperature drift is an important factor for improving the performance of FOG.A trend term of temperature drift of FOG is obtained using stationary wavelets transform,and an FOG drift algorithm with least square... Large temperature drift is an important factor for improving the performance of FOG.A trend term of temperature drift of FOG is obtained using stationary wavelets transform,and an FOG drift algorithm with least squares wavelet support vector machine(LS-WSVM) is developed.The algorithm used Maxihat wavelet as a kernel function of LS-WSVM to establish an FOG drift model.It has better modeling precise than LS-WSVM model with Gauss kernel.Results indicate the efficiency of this algorithm of LS-WSVM. 展开更多
关键词 人工智能 自动推理 光学陀螺仪 输入设备
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Software Residual defects Prediction Model based on BBNs
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作者 Zheng,Cuifang Wu, Zhijie Xia,Tao Zhang,Weiyan 《微计算机信息》 北大核心 2006年第01X期272-274,共3页
The importance of software residual defects and some prediction residual defects models are introduced. The problem that is not easy adapted to a general model is discussed. The model of prediction residual defects ba... The importance of software residual defects and some prediction residual defects models are introduced. The problem that is not easy adapted to a general model is discussed. The model of prediction residual defects based on BBNs is proposed and the detailed processes of the approach are given. 展开更多
关键词 软件缺陷 残差 BBNs 预测模型
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A Routing Optimization Algorithm with Quality of Multi- Service in Wireless Sensor Network
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作者 Jing Gong Lina Yuan 《International Journal of Technology Management》 2015年第3期76-78,共3页
关键词 无线传感器网络 服务质量 优化算法 路由选择 平衡网络 能量消耗 模拟实验 隶属度函数
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A Novel Multivariate Polynomial Approximation Factorization of Big Data
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作者 Guotao Luo Guang Pei 《国际计算机前沿大会会议论文集》 2015年第1期145-147,共3页
In actual engineering, processing of big data sometimes requires building of mass physical models, while processing of physical model requires relevant math model, thus producing mass multivariate polynomials, the eff... In actual engineering, processing of big data sometimes requires building of mass physical models, while processing of physical model requires relevant math model, thus producing mass multivariate polynomials, the effective reduction of which is a difficult problem at present. A novel algorithm is proposed to achieve the approximation factorization of complex coefficient multivariate polynomial in light of characteristics of multivariate polynomials. At first, the multivariate polynomial is reduced to be the binary polynomial, then the approximation factorization of binary polynomial can produce irreducible duality factor, at last, the irreducible duality factor is restored to the irreducible multiple factor. As a unit root is cyclic, selecting the unit root as the reduced factor can ensure the coefficient does not expand in a reduction process. Chinese remainder theorem is adopted in the corresponding reduction process, which brought down the calculation complexity. The algorithm is based on approximation factorization of binary polynomial and calculation of approximation Greatest Common Divisor, GCD. The algorithm can solve the reduction of multivariate polynomials in massive math models, which can obtain effectively null point of multivariate polynomials, providing a new approach for further analysis and explanation of physical models. The experiment result shows that the irreducible factors from this method get close to the real factors with high efficiency. 展开更多
关键词 Mass physical model MULTIVARIATE POLYNOMIAL APPROXIMATION factorization.Reduction Unit root.Binary APPROXIMATION FACTORIZATION APPROXIMATION GCD algorithm
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Key Technologies of Traditional Chinese Medicine Traceability Based on Internet of Things
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作者 Lei Yu Fangliang Huang +3 位作者 Yong Yang Qunshan Tao Tongping Shen Luyao Zhang 《国际计算机前沿大会会议论文集》 2019年第2期554-555,共2页
Compared with western medicine, there are many complicated factors affecting the intrinsic quality of traditional Chinese medicine, because its production needs to be planted, harvested, processed, transported, stored... Compared with western medicine, there are many complicated factors affecting the intrinsic quality of traditional Chinese medicine, because its production needs to be planted, harvested, processed, transported, stored, and sold, etc. Therefore, the internet of things is integrated into the traceability of traditional Chinese medicine, and its key technologies are studied. An XMLbased traceability information exchange model was constructed for traditional Chinese medicine and modeled the traceability process by the finite state machine (FSM). Furthermore, the specific electronic product code (EPC) coding scheme of traditional Chinese medicine was proposed based on the EPC coding structure model. Finally, the effectiveness of the above models and schemes is verified by an example of a traditional Chinese medicine traceability prototype system. 展开更多
关键词 TRADITIONAL Chinese MEDICINE Internet of THINGS TRACEABILITY Finite state machine Electronic product code
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Long Short Term Memory Networks Based Anomaly Detection for KPIs 被引量:2
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作者 Haiqi Zhu Fanzhi Meng +4 位作者 Seungmin Rho Mohan Li Jianyu Wang Shaohui Liu Feng Jiang 《Computers, Materials & Continua》 SCIE EI 2019年第8期829-847,共19页
In real-world many internet-based service companies need to closely monitor large amounts of data in order to ensure stable operation of their business.However,anomaly detection for these data with various patterns an... In real-world many internet-based service companies need to closely monitor large amounts of data in order to ensure stable operation of their business.However,anomaly detection for these data with various patterns and data quality has been a great challenge,especially without labels.In this paper,we adopt an anomaly detection algorithm based on Long Short-Term Memory(LSTM)Network in terms of reconstructing KPIs and predicting KPIs.They use the reconstruction error and prediction error respectively as the criteria for judging anomalies,and we test our method with real data from a company in the insurance industry and achieved good performance. 展开更多
关键词 LSTM anomaly detection KPIs
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A Convolution-Based System for Malicious URLs Detection 被引量:1
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作者 Chaochao Luo Shen Su +3 位作者 Yanbin Sun Qingji Tan Meng Han Zhihong Tian 《Computers, Materials & Continua》 SCIE EI 2020年第1期399-411,共13页
Since the web service is essential in daily lives,cyber security becomes more and more important in this digital world.Malicious Uniform Resource Locator(URL)is a common and serious threat to cybersecurity.It hosts un... Since the web service is essential in daily lives,cyber security becomes more and more important in this digital world.Malicious Uniform Resource Locator(URL)is a common and serious threat to cybersecurity.It hosts unsolicited content and lure unsuspecting users to become victim of scams,such as theft of private information,monetary loss,and malware installation.Thus,it is imperative to detect such threats.However,traditional approaches for malicious URLs detection that based on the blacklists are easy to be bypassed and lack the ability to detect newly generated malicious URLs.In this paper,we propose a novel malicious URL detection method based on deep learning model to protect against web attacks.Specifically,we firstly use auto-encoder to represent URLs.Then,the represented URLs will be input into a proposed composite neural network for detection.In order to evaluate the proposed system,we made extensive experiments on HTTP CSIC2010 dataset and a dataset we collected,and the experimental results show the effectiveness of the proposed approach. 展开更多
关键词 CNN anomaly detection web security auto-encoder deep learning
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An unsymmetric constitutive equation for anisotropic viscoelastic fluid 被引量:2
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作者 Shifang Han 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2007年第2期149-158,共10页
A continuum constitutive theory of corotational derivative type is developed for the anisotropic viscoelastic fluid-liquid crystalline (LC) polymers. A concept of anisotropic viscoelastic simple fluid is introduced.... A continuum constitutive theory of corotational derivative type is developed for the anisotropic viscoelastic fluid-liquid crystalline (LC) polymers. A concept of anisotropic viscoelastic simple fluid is introduced. The stress tensor instead of the velocity gradient tensor D in the classic Leslie-Ericksen theory is described by the first Rivlin-Ericksen tensor A and a spin tensor W measured with respect to a co-rotational coordinate system. A model LCP-H on this theory is proposed and the characteristic unsymmetric behaviour of the shear stress is predicted for LC polymer liquids. Two shear stresses thereby in shear flow of LC polymer liquids lead to internal vortex flow and rotational flow. The conclusion could be of theoretical meaning for the modern liquid crystalline display technology. By using the equation, extrusion-extensional flows of the fluid are studied for fiber spinning of LC polymer melts, the elongational viscosity vs. extension rate with variation of shear rate is given in figures. A considerable increase of elongational viscosity and bifurcation behaviour are observed when the orientational motion of the director vector is considered. The contraction of extru- date of LC polymer melts is caused by the high elongational viscosity. For anisotropic viscoelastic fluids, an important advance has been made in the investigation on the constitutive equation on the basis of which a seriesof new anisotropic non-Newtonian fluid problems can be addressed. 展开更多
关键词 Unsymmetric constitutive equation .Co-rotational derivative type.Anisotropic simple fluid . Liquid crystalline polymer .Extrusion- extensional flow
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Hydrodynamics Research on Amphibious Vehicle Systems:Modeling Theory
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作者 居乃鵕 《Defence Technology(防务技术)》 SCIE EI CAS 2006年第1期14-21,共8页
For completing the hydrodynamics software development and the engineering application research on the amphibious vehicle systems, hydrodynamic modeling theory of the amphibious vehicle systems is elaborated, which inc... For completing the hydrodynamics software development and the engineering application research on the amphibious vehicle systems, hydrodynamic modeling theory of the amphibious vehicle systems is elaborated, which includes to build up the dynamic system model of amphibious vehicle motion on water, gun tracking-aiming-firing, bullet hit and armored check-target, gunner operating control, and the simulation computed model of time domain for random sea wave. 展开更多
关键词 水动力学 水陆两用船 动力系统模型 海波 建模理论
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0.8μm LDD CMOS RELIABILITY EXPERIMENTS AND ANALYSIS
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作者 余山 章定康 黄敞 《Journal of Electronics(China)》 1995年第1期84-89,共6页
The numerical simulation of two dimensional device is conducted to describe the mechanism of the special substrate current and degradation of submicron LDD structure observed in experiments, and finally, the optimum p... The numerical simulation of two dimensional device is conducted to describe the mechanism of the special substrate current and degradation of submicron LDD structure observed in experiments, and finally, the optimum processes for submicron LDD CMOS are proposed. 展开更多
关键词 SUBMICRON LDD DEVICE Simulation RELIABILITY
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Non-Local DWI Image Super-Resolution with Joint Information Based on GPU Implementation
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作者 Yanfen Guo Zhe Cui +2 位作者 Zhipeng Yang Xi Wu Shaahin Madani 《Computers, Materials & Continua》 SCIE EI 2019年第9期1205-1215,共11页
Since the spatial resolution of diffusion weighted magnetic resonance imaging(DWI)is subject to scanning time and other constraints,its spatial resolution is relatively limited.In view of this,a new non-local DWI imag... Since the spatial resolution of diffusion weighted magnetic resonance imaging(DWI)is subject to scanning time and other constraints,its spatial resolution is relatively limited.In view of this,a new non-local DWI image super-resolution with joint information method was proposed to improve the spatial resolution.Based on the non-local strategy,we use the joint information of adjacent scan directions to implement a new weighting scheme.The quantitative and qualitative comparison of the datasets of synthesized DWI and real DWI show that this method can significantly improve the resolution of DWI.However,the algorithm ran slowly because of the joint information.In order to apply the algorithm to the actual scene,we compare the proposed algorithm on CPU and GPU respectively.It is found that the processing time on GPU is much less than on CPU,and that the highest speedup ratio to the traditional algorithm is more than 26 times.It raises the possibility of applying reconstruction algorithms in actual workplaces. 展开更多
关键词 SUPER-RESOLUTION non-local means parallel computing GPU
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Multi-agent Belief,Goal and Exceptions Reasoning
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作者 赖贤伟 胡山立 +1 位作者 宁正元 王秀丽 《Journal of Donghua University(English Edition)》 EI CAS 2010年第2期165-168,共4页
Temporal logics are often adopted as basic tools to specifying mental states such as belief and goal of agents. Although there are works on non-monotonic extension of linear temporal logic (LTL) and branching time tem... Temporal logics are often adopted as basic tools to specifying mental states such as belief and goal of agents. Although there are works on non-monotonic extension of linear temporal logic (LTL) and branching time temporal logic (CTL),the non-monotonic extension of alternating-time temporal logic (ATL) which is an important kind of multi-agent cooperation logics has not been discussed yet in literature. To solve this problem,this paper proposed non-monotonic alternating-time temporal logic with belief and goal,namely N-ATL-BG,to facilitate the non-monotonic reasoning of mental states of agents. The semantic model,syntax and semantics of this new logic are developed. A model checking algorithm which can be finished in polynomial time is proposed for this new logic. Examples are given to show its usage. 展开更多
关键词 多代理人合作逻辑 心理状态 例外
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