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Mutual Information Maximization via Joint Power Allocation in Integrated Sensing and Communications System
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作者 Jia Zhu Junsheng Mu +1 位作者 Yuanhao Cui Xiaojun Jing 《China Communications》 SCIE CSCD 2024年第2期129-142,共14页
In this paper, we focus on the power allocation of Integrated Sensing and Communication(ISAC) with orthogonal frequency division multiplexing(OFDM) waveform. In order to improve the spectrum utilization efficiency in ... In this paper, we focus on the power allocation of Integrated Sensing and Communication(ISAC) with orthogonal frequency division multiplexing(OFDM) waveform. In order to improve the spectrum utilization efficiency in ISAC, we propose a design scheme based on spectrum sharing, that is,to maximize the mutual information(MI) of radar sensing while ensuring certain communication rate and transmission power constraints. In the proposed scheme, three cases are considered for the scattering off the target due to the communication signals,as negligible signal, beneficial signal, and interference signal to radar sensing, respectively, thus requiring three power allocation schemes. However,the corresponding power allocation schemes are nonconvex and their closed-form solutions are unavailable as a consequence. Motivated by this, alternating optimization(AO), sequence convex programming(SCP) and Lagrange multiplier are individually combined for three suboptimal solutions corresponding with three power allocation schemes. By combining the three algorithms, we transform the non-convex problem which is difficult to deal with into a convex problem which is easy to solve and obtain the suboptimal solution of the corresponding optimization problem. Numerical results show that, compared with the allocation results of the existing algorithms, the proposed joint design algorithm significantly improves the radar performance. 展开更多
关键词 COEXISTENCE COMMUNICATIONS multicarrier radar mutual information spectrum sharing
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Mutual Authentication Protocols for RFID Systems 被引量:3
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作者 Ashrar A.Omer Johnson P.Thomas 《International Journal of Automation and computing》 EI 2008年第4期348-365,共18页
With the availability of low-cost radio frequency identification (RFID) tags,security becomes an increasing concern. However,such tags do not permit complex cryptographic functions due to their computational,communica... With the availability of low-cost radio frequency identification (RFID) tags,security becomes an increasing concern. However,such tags do not permit complex cryptographic functions due to their computational,communications,and storage limitations. In this paper,we investigate the security issues and requirements of RFID systems,and propose ultra-light weight and light weight protocols for low-cost RFID tags.The proposed protocols has been applied to a supply chain management system. 展开更多
关键词 SECURITY mutual authentication supply chain management RFID systems.
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An Enhanced Direct Anonymous Attestation Scheme with Mutual Authentication for Network-Connected UAV Communication Systems 被引量:3
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作者 Liquan Chen Sijie Qian +1 位作者 Ming Lim Shihui Wang 《China Communications》 SCIE CSCD 2018年第5期61-76,共16页
In network-connected UAV(NCUAV) communication systems, user authentication is replaced by platform identity authentication and integrity check because many NC-UAVs are operated without human intervention. Direct anony... In network-connected UAV(NCUAV) communication systems, user authentication is replaced by platform identity authentication and integrity check because many NC-UAVs are operated without human intervention. Direct anonymous attestation(DAA) is an attractive cryptographic scheme that provides an elegant balance between platform authentication and anonymity. However, because of the low-level computing capability and limited transmission bandwidth in UAV, the existing DAA schemes are not suitable for NC-UAV communication systems. In this paper, we propose an enhanced DAA scheme with mutual authentication(MA-DAA scheme), which meets the security requirements of NC-UAV communication systems. The proposed MA-DAA scheme, which is based on asymmetric pairings, bundles the identities of trusted platform module(TPM) and Host to solve the malicious module changing attacks. Credential randomization, batch proof and verification, and mutual authentication are realized in the MA-DAA scheme. The computational workload in TPM and Host is reduced in order to meet the low computation and resource requirements in TPM and Host.The entire scheme and protocols are presented,and the security and efficiency of the proposed MA-DAA scheme are proved and analyzed.Our experiment results also confirm the high efficiency of the proposed scheme. 展开更多
关键词 network-connected UAV trusted computing direct anonymous attestation mutual authentication trusted platform module
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Stability Analysis and Hopf Bifurcation for ODE System of Predator-Prey Model with Mutual Interference 被引量:3
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作者 Khalid Ahmed Abbakar Yafei Yang +3 位作者 Alhussein Mohamed Songchen Xia Mogahid Mamoon Abkar Omer Bushra Elfadil Hassan 《Applied Mathematics》 2021年第9期793-802,共10页
In this paper, the temporal and spatial patterns of a diffusive predator-prey model with mutual interference under homogeneous Neumann boundary conditions were studied. Specifically, first, taking the intrinsic growth... In this paper, the temporal and spatial patterns of a diffusive predator-prey model with mutual interference under homogeneous Neumann boundary conditions were studied. Specifically, first, taking the intrinsic growth rate of the predator as the parameter, we give a computational and theoretical analysis of Hopf bifurcation on the positive equilibrium for the ODE system. As well, we have discussed the conditions for determining the bifurcation direction and the stability of the bifurcating periodic solutions. 展开更多
关键词 Predator-Prey Model mutual Interference Hopf Bifurcation Functional Response
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Experience and Enlightenment of the Fishery Mutual Insurance System in Asian Countries 被引量:1
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作者 Hongmin LI 《Asian Agricultural Research》 2013年第8期127-130,共4页
Asia is the major producing area of aquatic products.In order to maintain the stability of fishery,some Asian countries have established a mutual insurance system,which,however,shows distinctive features in different ... Asia is the major producing area of aquatic products.In order to maintain the stability of fishery,some Asian countries have established a mutual insurance system,which,however,shows distinctive features in different countries as a result of their different historical,economic and social conditions.This paper introduced the development status and characteristics of the fishery mutual insurance system in some Asian countries,such as Japan,South Korea,India,etc.,and then summarized their experiences and what we can learn from their experiences from the perspectives of legislation,governmental support,mutual insurance associations,and credit. 展开更多
关键词 ASIAN COUNTRIES FISHERY mutual INSURANCE mutual in
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A TRIBAND SWASTIKA SHAPED PATCH ANTENNA WITH REDUCED MUTUAL COUPLING FOR WIRELESS MIMO SYSTEMS 被引量:1
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作者 K Jagadeesh Babu K Sri Ramakrishna L Pratap Reddy 《Journal of Electronics(China)》 2011年第4期483-487,共5页
A novel compact Swastika shaped patch antenna is designed in the present work,which can be used for Multiple Input Multiple Output(MIMO) systems.The proposed two element MIMO system resonates at a triband of 3.3 GHz,5... A novel compact Swastika shaped patch antenna is designed in the present work,which can be used for Multiple Input Multiple Output(MIMO) systems.The proposed two element MIMO system resonates at a triband of 3.3 GHz,5.8 GHz,and 7.1 GHz with an improved impedance bandwidth of 37% and a reduced mutual coupling of-33 dB.These results are better compared to a normal E shaped patch antenna designed with same size and thickness,achieved without using any additional decoupling methods.A 2×2 MIMO system employing the Swastika shaped patch antennas is analyzed using computational electromagnetic ray tracing software for an indoor environment.The results show an improvement in the capacity compared to a 2×2 MIMO system developed with dipole antennas.The proposed antenna is a good choice for MIMO systems operating for several Ultra WideBand(UWB) applications. 展开更多
关键词 Swastika shaped patch antenna Multiple Input Multiple Output(MIMO) Impedance bandwidth mutual coupling Capacity
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Performance of Block Diagonalization Broadcasting Scheme for Multiuser MIMO System Operating in Presence of Spatial Correlation and Mutual Coupling 被引量:1
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作者 Feng Wang Marek E Bialkowski Xia Liu 《International Journal of Communications, Network and System Sciences》 2010年第3期266-272,共7页
In this paper, the capacity of a multiuser Multiple Input Multiple Output (MIMO) system employing the block diagonalization broadcasting scheme in presence of spatial correlation and mutual coupling is investigated. I... In this paper, the capacity of a multiuser Multiple Input Multiple Output (MIMO) system employing the block diagonalization broadcasting scheme in presence of spatial correlation and mutual coupling is investigated. It is shown by computer simulations that, in general, the presence of spatial correlation decreases the capacity of a multiuser MIMO system. However, for some particular antenna element spacing mutual coupling decreases the spatial correlation rendering an increased capacity. The optimized diagonalization broadcasting technique with a two-stage power allocation scheme is proposed and verified. The presented simulations results confirm the advantage of the proposed broadcasting scheme. 展开更多
关键词 MULTIUSER MIMO BLOCK Diagonalizaiton mutual COUPLING Dirty PAPER CODING
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A Unified Mutual Coupling Model for Multiple Antenna Systems 被引量:1
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作者 伍裕江 聂在平 《Journal of Electronic Science and Technology of China》 2006年第2期123-126,共4页
A unified mutual coupling model for multiple antenna communication systems based on moment methods is proposed. This model combines antenna coupling and RF front-end circuit coupling, thus providing a more accurate an... A unified mutual coupling model for multiple antenna communication systems based on moment methods is proposed. This model combines antenna coupling and RF front-end circuit coupling, thus providing a more accurate and complete analysis of the mutual coupling effect on multiple antenna systems. 展开更多
关键词 MIMO mutual coupling pattern diversity
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Synchronization in a Mutualism Ecosystem Induced by Noise Correlation
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作者 ZHONG Wei-Rong SHAO Yuan-Zhi +1 位作者 BIE Meng-Jie HE Zhen-Hui 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第9期793-796,共4页
Understanding the cause of the synchronization of population evolution is an important issue for ecologicalimprovement.Here we present a Lotka-Volterra-type model driven by two correlated environmental noises and show... Understanding the cause of the synchronization of population evolution is an important issue for ecologicalimprovement.Here we present a Lotka-Volterra-type model driven by two correlated environmental noises and show,via theoretical analysis and direct simulation,that noise correlation can induce a synchronization of the mutualists.Thetime series of mutual species exhibit a chaotic-like fluctuation,which is independent of the noise correlation,however,the chaotic fluctuation of mutual species ratio decreases with the noise correlation.A quantitative parameter defined forcharacterizing chaotic fluctuation provides a good approach to measure when the complete synchronization happens. 展开更多
关键词 environmental noise CORRELATION synchronous fluctuation CHAOS population dynamics mutualISM
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A new mutually destabilized reactive hydride system:LiBH4–Mg2NiH4
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作者 Nils Bergemann Claudio Pistidda +6 位作者 Maike Uptmoor Chiara Milanese Antonio Santoru Thomas Emmler Julián Puszkiel Martin Dornheim Thomas Klassen 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2019年第7期240-254,共15页
In this work,the hydrogen sorption properties of the LiBH4-Mg2NiH4 composite system with the molar ratio 2:2.5 were thoroughly investigated as a function of the applied temperature and hydrogen pressure.To the best of... In this work,the hydrogen sorption properties of the LiBH4-Mg2NiH4 composite system with the molar ratio 2:2.5 were thoroughly investigated as a function of the applied temperature and hydrogen pressure.To the best of our knowledge,it has been possible to prove experimentally the mutual destabilization between LiBH4 and Mg2NiH4.A detailed account of the kinetic and thermodynamic features of the dehydrogenation process is reported here. 展开更多
关键词 Hydrogen storage Metal hydrides BOROHYDRIDES REACTIVE HYDRIDE Composites(RHC) mutual DESTABILIZATION TERNARY borides
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Using mutual information to evaluate performance of medical imaging systems
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作者 Eri Matsuyama Du-Yih Tsai +1 位作者 Yongbum Lee Katsuyuki Kojima 《Health》 2010年第4期279-285,共7页
Information on physical image quality of medical images is important for imaging system assessment in order to promote and stimulate the development of state-of-the-art imaging systems. In this paper, we present a met... Information on physical image quality of medical images is important for imaging system assessment in order to promote and stimulate the development of state-of-the-art imaging systems. In this paper, we present a method for evaluating physical performance of medical imaging systems. In this method, mutual information (MI) which is a concept from information theory was used to measure combined properties of image noise and resolution of an imaging system. In our study, the MI was used as a measure to express the amount of information that an output image contains about an input object. The more the MI value provides, the better the image quality is. To validate the proposed method, computer simulations were per- formed to investigate the effects of noise and resolution degradation on the MI, followed by measuring and comparing the performance of two imaging systems. Our simulation and experimental results confirmed that the combined effect of deteriorated blur and noise on the images can be measured and analyzed using the MI metric. The results demonstrate the potential usefulness of the proposed method for evaluating physical quality of medical imaging systems. 展开更多
关键词 IMAGE QUALITY MEDICAL IMAGING mutual INFORMATION
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An Analysis of Mutual Interference in Radar Systems Using Dual-Band (Ka / X) Antennas
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作者 DU Shimin, Beijing Institute of Radio Measurement, P.O.Box 3923-2, Beijing 100854, China WANG Baofa, Beijing University of Aeronautics and Astronautics, Beijing, China WU Yi, No.2 Radio Instrument Factory of Beijing, Beijing, China 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1992年第4期84-87,共4页
An analysis of mutual interfering sources on RF systems using dual-band (Ka / X) radar is presented. The purpose of this paper is to improve operational performance of the system from the point of view of EMC design. ... An analysis of mutual interfering sources on RF systems using dual-band (Ka / X) radar is presented. The purpose of this paper is to improve operational performance of the system from the point of view of EMC design. The experimental dual-band antenna system have decreased the disturbing effects of most mutual interfering sources. 展开更多
关键词 ANTENNAS KA An Analysis of mutual Interference in Radar systems Using Dual-Band
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THE BOUNDED EXTERMINATION AND STABILITY OF MUTUAL INTERFERENCE SYSTEM OF FOUR-DIMENSIONAL SPECIES
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作者 侯赣生 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1994年第11期1035-1045,共11页
This paper considers a typical mutual interference system of four-dimensionalspecies, its bounded, extermination stability are studied, and their necessary-sufficientcondition are given, and their ecology meaning set ... This paper considers a typical mutual interference system of four-dimensionalspecies, its bounded, extermination stability are studied, and their necessary-sufficientcondition are given, and their ecology meaning set forth. 展开更多
关键词 mutual interference system. bounded. extermination equilibrium.stability
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Reduction of Systematic Error in Radiopharmaceutical Activity by Entropy Based Mutual Information
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作者 Palliyakarany T. K. Kumar Toshikazu Takeda 《World Journal of Nuclear Science and Technology》 2012年第1期1-5,共5页
The quality of the radiation dose depends upon the gamma count rate of the radionuclide used. Any reduction in error in the count rate is reflected in the reduction in error in the activity and consequently on the qua... The quality of the radiation dose depends upon the gamma count rate of the radionuclide used. Any reduction in error in the count rate is reflected in the reduction in error in the activity and consequently on the quality of dose. All the efforts so far have been directed only to minimize the random errors in count rate by repetition. In the absence of probability distribution for the systematic errors, we propose to minimize these errors by estimating the upper and lower limits by the technique of determinant in equalities developed by us. Using the algorithm we have developed based on the tech- nique of determinant inequalities and the concept of maximization of mutual information (MI), we show how to process element by element of the covariance matrix to minimize the correlated systematic errors in the count rate of 113 mIn. The element wise processing of covariance matrix is so unique by our technique that it gives experimentalists enough maneuverability to mitigate different factors causing systematic errors in the count rate and consequently the activity of 113 mIn. 展开更多
关键词 Random and systematic ERRORS Covariance Matrix Limits for Correlated Elements by DETERMINANT INEQUALITIES mutual INFORMATION REDUCTION of systematic ERRORS by Maximizing mutual INFORMATION
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Adaptive Isochronal Synchronization in Mutually Coupled Chaotic Systems
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作者 Da Lin Hong Song +1 位作者 Yi Yao Fuchen Zhang 《Journal of Modern Physics》 2015年第2期150-156,共7页
This paper studies the problem of isochronal synchronization of chaotic systems with time-delayed mutual coupling. Based on the invariance principle of differential equations, an adaptive feedback scheme is proposed f... This paper studies the problem of isochronal synchronization of chaotic systems with time-delayed mutual coupling. Based on the invariance principle of differential equations, an adaptive feedback scheme is proposed for the stability of isochronal synchronization between two identical chaotic systems. Unlike the usual linear feedback, the variable feedback strength is automatically adapted to isochronally synchronize two identical chaotic systems with delay-coupled, so this scheme is analytical, and simple to implement in practice. Simulation results show that the isochronal synchronization behavior is determined by time delay. 展开更多
关键词 Isochronal SYNCHRONIZATION mutual COUPLING ADAPTIVE CONTROL
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New construction of mutually unbiased bases for odd-dimensional state space
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作者 王成红 王昆 郑驻军 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第8期180-184,共5页
We study the construction of mutually unbiased bases in Hilbert space for composite dimensions d which are not prime powers.We explore the results for composite dimensions which are true for prime power dimensions.We ... We study the construction of mutually unbiased bases in Hilbert space for composite dimensions d which are not prime powers.We explore the results for composite dimensions which are true for prime power dimensions.We then provide a method for selecting mutually unbiased vectors from the eigenvectors of generalized Pauli matrices to construct mutually unbiased bases.In particular,we present four mutually unbiased bases in C^(15). 展开更多
关键词 mutually unbiased bases Hilbert space Pauli matrix quantum measurement
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Quantized Decoders that Maximize Mutual Information for Polar Codes
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作者 Zhu Hongfei Cao Zhiwei +1 位作者 Zhao Yuping Li Dou 《China Communications》 SCIE CSCD 2024年第7期125-134,共10页
In this paper,we innovatively associate the mutual information with the frame error rate(FER)performance and propose novel quantized decoders for polar codes.Based on the optimal quantizer of binary-input discrete mem... In this paper,we innovatively associate the mutual information with the frame error rate(FER)performance and propose novel quantized decoders for polar codes.Based on the optimal quantizer of binary-input discrete memoryless channels(BDMCs),the proposed decoders quantize the virtual subchannels of polar codes to maximize mutual information(MMI)between source bits and quantized symbols.The nested structure of polar codes ensures that the MMI quantization can be implemented stage by stage.Simulation results show that the proposed MMI decoders with 4 quantization bits outperform the existing nonuniform quantized decoders that minimize mean-squared error(MMSE)with 4 quantization bits,and yield even better performance than uniform MMI quantized decoders with 5 quantization bits.Furthermore,the proposed 5-bit quantized MMI decoders approach the floating-point decoders with negligible performance loss. 展开更多
关键词 maximize mutual information polar codes QUANTIZATION successive cancellation decoding
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Analytical modeling and approaches of multihelix cables incorporating with interwire mutual contacts
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作者 Zhichao ZHANG Xingzhe WANG 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第9期1633-1654,共22页
This study aims to develop an analytical model based on the curve beam theory to capture the mechanical response of a multihelix cable considering the internal contact displacements.Accordingly,a double-helix cable su... This study aims to develop an analytical model based on the curve beam theory to capture the mechanical response of a multihelix cable considering the internal contact displacements.Accordingly,a double-helix cable subjected to axial tension and torsion is analyzed,and both the line and point contacts between the neighboring wires and strands are considered via an equivalent homogenized approach.Then,the proposed theoretical model is extended to a hierarchical multihelix cable with mutual contact displacements by constructing a recursive relationship between the high-and low-level multihelix structures.The global tensile stiffness and torsional stiffness of the double-helix cable are successfully evaluated.The results are validated by a finite element(FE)model,and are found to be consistent with the findings of previous studies.It is shown that the contact deformations in multihelix cables significantly affect their equivalent mechanical stiffness,and the contact displacements are remarkably enhanced as the helix angles increase.This study provides insights into the interwire/interstrand mutual contact effects on global and local responses. 展开更多
关键词 wordshierarchical multihelix cable mutual contact effect mechanical response effective stiffness
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Robust and Discriminative Feature Learning via Mutual Information Maximization for Object Detection in Aerial Images
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作者 Xu Sun Yinhui Yu Qing Cheng 《Computers, Materials & Continua》 SCIE EI 2024年第9期4149-4171,共23页
Object detection in unmanned aerial vehicle(UAV)aerial images has become increasingly important in military and civil applications.General object detection models are not robust enough against interclass similarity an... Object detection in unmanned aerial vehicle(UAV)aerial images has become increasingly important in military and civil applications.General object detection models are not robust enough against interclass similarity and intraclass variability of small objects,and UAV-specific nuisances such as uncontrolledweather conditions.Unlike previous approaches focusing on high-level semantic information,we report the importance of underlying features to improve detection accuracy and robustness fromthe information-theoretic perspective.Specifically,we propose a robust and discriminative feature learning approach through mutual information maximization(RD-MIM),which can be integrated into numerous object detection methods for aerial images.Firstly,we present the rank sample mining method to reduce underlying feature differences between the natural image domain and the aerial image domain.Then,we design a momentum contrast learning strategy to make object features similar to the same category and dissimilar to different categories.Finally,we construct a transformer-based global attention mechanism to boost object location semantics by leveraging the high interrelation of different receptive fields.We conduct extensive experiments on the VisDrone and Unmanned Aerial Vehicle Benchmark Object Detection and Tracking(UAVDT)datasets to prove the effectiveness of the proposed method.The experimental results show that our approach brings considerable robustness gains to basic detectors and advanced detection methods,achieving relative growth rates of 51.0%and 39.4%in corruption robustness,respectively.Our code is available at https://github.com/cq100/RD-MIM(accessed on 2 August 2024). 展开更多
关键词 Aerial images object detection mutual information contrast learning attention mechanism
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A novel fracture-cavity reservoir outcrop geological knowledge base construction method considering parameter collection and processing,mutual transformation of data-knowledge,application and update
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作者 Qi-Qiang Ren Jin-Liang Gao +4 位作者 Peng Zhu Meng-Ping Li Jian-Wei Feng Qiang Jin San Zhang 《Petroleum Science》 SCIE EI CAS CSCD 2024年第4期2184-2202,共19页
This study endeavors to formulate a comprehensive methodology for establishing a Geological Knowledge Base(GKB)tailored to fracture-cavity reservoir outcrops within the North Tarim Basin.The acquisition of quantitativ... This study endeavors to formulate a comprehensive methodology for establishing a Geological Knowledge Base(GKB)tailored to fracture-cavity reservoir outcrops within the North Tarim Basin.The acquisition of quantitative geological parameters was accomplished through diverse means such as outcrop observations,thin section studies,unmanned aerial vehicle scanning,and high-resolution cameras.Subsequently,a three-dimensional digital outcrop model was generated,and the parameters were standardized.An assessment of traditional geological knowledge was conducted to delineate the knowledge framework,content,and system of the GKB.The basic parameter knowledge was extracted using multiscale fine characterization techniques,including core statistics,field observations,and microscopic thin section analysis.Key mechanism knowledge was identified by integrating trace elements from filling,isotope geochemical tests,and water-rock simulation experiments.Significant representational knowledge was then extracted by employing various methods such as multiple linear regression,neural network technology,and discriminant classification.Subsequently,an analogy study was performed on the karst fracture-cavity system(KFCS)in both outcrop and underground reservoir settings.The results underscored several key findings:(1)Utilization of a diverse range of techniques,including outcrop observations,core statistics,unmanned aerial vehicle scanning,high-resolution cameras,thin section analysis,and electron scanning imaging,enabled the acquisition and standardization of data.This facilitated effective management and integration of geological parameter data from multiple sources and scales.(2)The GKB for fracture-cavity reservoir outcrops,encompassing basic parameter knowledge,key mechanism knowledge,and significant representational knowledge,provides robust data support and systematic geological insights for the intricate and in-depth examination of the genetic mechanisms of fracture-cavity reservoirs.(3)The developmental characteristics of fracturecavities in karst outcrops offer effective,efficient,and accurate guidance for fracture-cavity research in underground karst reservoirs.The outlined construction method of the outcrop geological knowledge base is applicable to various fracture-cavity reservoirs in different layers and regions worldwide. 展开更多
关键词 Geological knowledge base Karst fracture-cavity system mutual transformation of data-knowledge Knowledge base content and application Tarim basin
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