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Optimization of the Use of Spherical Targets for Point Cloud Registration Using Monte Carlo Simulation
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作者 CHAN Ting On XIAO Hang +3 位作者 XIA Linyuan LICHTI Derek D LI Ming Ho DU Guoming 《Journal of Geodesy and Geoinformation Science》 CSCD 2024年第2期18-36,共19页
Registrations based on the manual placement of spherical targets are still being employed by many professionals in the industry.However,the placement of those targets usually relies solely on personal experience witho... Registrations based on the manual placement of spherical targets are still being employed by many professionals in the industry.However,the placement of those targets usually relies solely on personal experience without scientific evidence supported by numerical analysis.This paper presents a comprehensive investigation,based on Monte Carlo simulation,into determining the optimal number and positions for efficient target placement in typical scenes consisting of a pair of facades.It demonstrates new check-up statistical rules and geometrical constraints that can effectively extract and analyze massive simulations of unregistered point clouds and their corresponding registrations.More than 6×10^(7) sets of the registrations were simulated,whereas more than IOO registrations with real data were used to verify the results of simulation.The results indicated that using five spherical targets is the best choice for the registration of a large typical registration site consisting of two vertical facades and a ground,when there is only a box set of spherical targets available.As a result,the users can avoid placing extra targets to achieve insignificant improvements in registration accuracy.The results also suggest that the higher registration accuracy can be obtained when the ratio between the facade-to-target distance and target-to-scanner distance is approximately 3:2.Therefore,the targets should be placed closer to the scanner rather than in the middle between the facades and the scanner,contradicting to the traditional thought. Besides,the results reveal that the accuracy can be increased by setting the largest projected triangular area of the targets to be large. 展开更多
关键词 point cloud registration Monte Carlo simulation optimalization spherical target
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Multiple model PHD filter for tracking sharply maneuvering targets using recursive RANSAC based adaptive birth estimation
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作者 DING Changwen ZHOU Di +2 位作者 ZOU Xinguang DU Runle LIU Jiaqi 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2024年第3期780-792,共13页
An algorithm to track multiple sharply maneuvering targets without prior knowledge about new target birth is proposed. These targets are capable of achieving sharp maneuvers within a short period of time, such as dron... An algorithm to track multiple sharply maneuvering targets without prior knowledge about new target birth is proposed. These targets are capable of achieving sharp maneuvers within a short period of time, such as drones and agile missiles.The probability hypothesis density (PHD) filter, which propagates only the first-order statistical moment of the full target posterior, has been shown to be a computationally efficient solution to multitarget tracking problems. However, the standard PHD filter operates on the single dynamic model and requires prior information about target birth distribution, which leads to many limitations in terms of practical applications. In this paper,we introduce a nonzero mean, white noise turn rate dynamic model and generalize jump Markov systems to multitarget case to accommodate sharply maneuvering dynamics. Moreover, to adaptively estimate newborn targets’information, a measurement-driven method based on the recursive random sampling consensus (RANSAC) algorithm is proposed. Simulation results demonstrate that the proposed method achieves significant improvement in tracking multiple sharply maneuvering targets with adaptive birth estimation. 展开更多
关键词 multitarget tracking probability hypothesis density(PHD)filter sharply maneuvering targets multiple model adaptive birth intensity estimation
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Deployment optimization for target perpetual coverage in energy harvesting wireless sensor network 被引量:1
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作者 Zhenkun Jin Yixuan Geng +4 位作者 Chenlu Zhu Yunzhi Xia Xianjun Deng Lingzhi Yi Xianlan Wang 《Digital Communications and Networks》 SCIE CSCD 2024年第2期498-508,共11页
Energy limitation of traditional Wireless Sensor Networks(WSNs)greatly confines the network lifetime due to generating and processing massive sensing data with a limited battery.The energy harvesting WSN is a novel ne... Energy limitation of traditional Wireless Sensor Networks(WSNs)greatly confines the network lifetime due to generating and processing massive sensing data with a limited battery.The energy harvesting WSN is a novel network architecture to address the limitation of traditional WSN.However,existing coverage and deployment schemes neglect the environmental correlation of sensor nodes and external energy with respect to physical space.Comprehensively considering the spatial correlation of the environment and the uneven distribution of energy in energy harvesting WSN,we investigate how to deploy a collection of sensor nodes to save the deployment cost while ensuring the target perpetual coverage.The Confident Information Coverage(CIC)model is adopted to formulate the CIC Minimum Deployment Cost Target Perpetual Coverage(CICMTP)problem to minimize the deployed sensor nodes.As the CICMTP is NP-hard,we devise two approximation algorithms named Local Greedy Threshold Algorithm based on CIC(LGTA-CIC)and Overall Greedy Search Algorithm based on CIC(OGSA-CIC).The LGTA-CIC has a low time complexity and the OGSA-CIC has a better approximation rate.Extensive simulation results demonstrate that the OGSA-CIC is able to achieve lower deployment cost and the performance of the proposed algorithms outperforms GRNP,TPNP and EENP algorithms. 展开更多
关键词 Energy harvesting WSN Deployment optimization Confident information coverage(CIC) target perpetual coverage
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Enhanced Precision Therapy of Multiple Myeloma Through Engineered Biomimetic Nanoparticles with Dual Targeting
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作者 Ruogu Qi Shanshan Wang +8 位作者 Jiayi Yu Tianming Lu Zhiqiang Bi Weibo Liu Yuanyuan Guo Yong Bian Jianliang Shen Xuesong Zhang Wenhao Hu 《Engineering》 SCIE EI CAS CSCD 2024年第5期178-192,共15页
Multiple myeloma(MM)is the second most prevalent hematological malignancy.Current MM treatment strategies are hampered by systemic toxicity and suboptimal therapeutic efficacy.This study addressed these limitations th... Multiple myeloma(MM)is the second most prevalent hematological malignancy.Current MM treatment strategies are hampered by systemic toxicity and suboptimal therapeutic efficacy.This study addressed these limitations through the development of a potent MM-targeting chemotherapy strategy,which capitalized on the high binding affinity of alendronate for hydroxyapatite in the bone matrix and the homologous targeting of myeloma cell membranes,termed T-PB@M.The results from our investigations highlight the considerable bone affinity of T-PB@M,both in vitro and in vivo.Additionally,this material demonstrated a capability for drug release triggered by low pH conditions.Moreover,T-PB@M induced the generation of reactive oxygen species and triggered cell apoptosis through the poly(ADP-ribose)polymerase 1(PARP1)-Caspase-3-B-cell lymphoma-2(Bcl-2)pathway in MM cells.Notably,T-PB@M preferentially targeted bone-involved sites,thereby circumventing systemic toxic side effects and leading to prolonged survival of MM orthotopic mice.Therefore,this designed target-MM nanocarrier presents a promising and potentially effective platform for the precise treatment of MM. 展开更多
关键词 multiple myeloma BORTEZOMIB Drug delivery Dual targeting Controlled release
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Battlefield target intelligence system architecture modeling and system optimization
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作者 LI Wei WANG Yue +2 位作者 JIA Lijuan PENG Senran HE Ruixi 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2024年第5期1190-1210,共21页
To address the current problems of poor generality,low real-time,and imperfect information transmission of the battlefield target intelligence system,this paper studies the battlefield target intelligence system from ... To address the current problems of poor generality,low real-time,and imperfect information transmission of the battlefield target intelligence system,this paper studies the battlefield target intelligence system from the top-level perspective of multi-service joint warfare.First,an overall planning and analysis method of architecture modeling is proposed with the idea of a bionic analogy for battlefield target intelligence system architecture modeling,which reduces the difficulty of the planning and design process.The method introduces the Department of Defense architecture framework(DoDAF)modeling method,the multi-living agent(MLA)theory modeling method,and other combinations for planning and modeling.A set of rapid planning methods that can be applied to model the architecture of various types of complex systems is formed.Further,the liveness analysis of the battlefield target intelligence system is carried out,and the problems of the existing system are presented from several aspects.And the technical prediction of the development and construction is given,which provides directional ideas for the subsequent research and development of the battlefield target intelligence system.In the end,the proposed architecture model of the battlefield target intelligence system is simulated and verified by applying the colored Petri nets(CPN)simulation software.The analysis demonstrates the reasonable integrity of its logic. 展开更多
关键词 battlefield target intelligence system architecture modeling bionic design system optimization simulation verification
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A combination algorithm of Chaos optimization and genetic algorithm and its application in maneuvering multiple targets data association
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作者 王建华 张琳 刘维亭 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2007年第4期470-473,共4页
The most important problem in targets tracking is data association which may be represented as a sort of constraint combinational optimization problem. Chaos optimization and adaptive genetic algorithm were used to de... The most important problem in targets tracking is data association which may be represented as a sort of constraint combinational optimization problem. Chaos optimization and adaptive genetic algorithm were used to deal with the problem of multi-targets data association separately. Based on the analysis of the limitation of chaos optimization and genetic algorithm, a new chaos genetic optimization combination algorithm was presented. This new algorithm first applied the "rough" search of chaos optimization to initialize the population of GA, then optimized the population by real-coded adaptive GA. In this way, GA can not only jump out of the "trap" of local optimal results easily but also increase the rate of convergence. And the new method can also avoid the complexity and time-consumed limitation of conventional way. The simulation results show that the combination algorithm can obtain higher correct association percent and the effect of association is obviously superior to chaos optimization or genetic algorithm separately. This method has better convergence property as well as time property than the conventional ones. 展开更多
关键词 data association chaos optimization genetic algorithm maneuvering multiple targets tracking
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Optimal search for moving targets with sensing capabilities using multiple UAVs 被引量:11
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作者 Xiaoxuan Hu Yanhong Liu Guoqiang Wang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2017年第3期526-535,共10页
This paper studies the problem of using multiple unmanned air vehicles (UAVs) to search for moving targets with sensing capabilities. When multiple UAVs (multi-UAV) search for a number of moving targets in the mission... This paper studies the problem of using multiple unmanned air vehicles (UAVs) to search for moving targets with sensing capabilities. When multiple UAVs (multi-UAV) search for a number of moving targets in the mission area, the targets can intermittently obtain the position information of the UAVs from sensing devices, and take appropriate actions to increase the distance between themselves and the UAVs. Aiming at this problem, an environment model is established using the search map, and the updating method of the search map is extended by considering the sensing capabilities of the moving targets. A multi-UAV search path planning optimization model based on the model predictive control (MPC) method is constructed, and a hybrid particle swarm optimization algorithm with a crossover operator is designed to solve the model. Simulation results show that the proposed method can effectively improve the cooperative search efficiency and can find more targets per unit time compared with the coverage search method and the random search method. 展开更多
关键词 unmanned air vehicle (UAV) moving target search model predictive control path planning hybrid particle swarm optimization
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Multi-Material Topology Optimization for Spatial-Varying Porous Structures 被引量:1
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作者 Chengwan Zhang Kai Long +4 位作者 Zhuo Chen Xiaoyu Yang Feiyu Lu Jinhua Zhang Zunyi Duan 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第1期369-390,共22页
This paper aims to propose a topology optimization method on generating porous structures comprising multiple materials.The mathematical optimization formulation is established under the constraints of individual volu... This paper aims to propose a topology optimization method on generating porous structures comprising multiple materials.The mathematical optimization formulation is established under the constraints of individual volume fraction of constituent phase or total mass,as well as the local volume fraction of all phases.The original optimization problem with numerous constraints is converted into a box-constrained optimization problem by incorporating all constraints to the augmented Lagrangian function,avoiding the parameter dependence in the conventional aggregation process.Furthermore,the local volume percentage can be precisely satisfied.The effects including the globalmass bound,the influence radius and local volume percentage on final designs are exploited through numerical examples.The numerical results also reveal that porous structures keep a balance between the bulk design and periodic design in terms of the resulting compliance.All results,including those for irregular structures andmultiple volume fraction constraints,demonstrate that the proposedmethod can provide an efficient solution for multiple material infill structures. 展开更多
关键词 Topology optimization porous structures local volume fraction augmented lagrangian multiple materials
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Online task planning method of anti-ship missile based on rolling optimization
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作者 LU Faxing DAI Qiuyang +1 位作者 YANG Guang JIA Zhengrong 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2024年第3期720-731,共12页
Based on the wave attack task planning method in static complex environment and the rolling optimization framework, an online task planning method in dynamic complex environment based on rolling optimization is propos... Based on the wave attack task planning method in static complex environment and the rolling optimization framework, an online task planning method in dynamic complex environment based on rolling optimization is proposed. In the process of online task planning in dynamic complex environment,online task planning is based on event triggering including target information update event, new target addition event, target failure event, weapon failure event, etc., and the methods include defense area reanalysis, parameter space update, and mission re-planning. Simulation is conducted for different events and the result shows that the index value of the attack scenario after re-planning is better than that before re-planning and according to the probability distribution of statistical simulation method, the index value distribution after re-planning is obviously in the region of high index value, and the index value gap before and after re-planning is related to the degree of posture change. 展开更多
关键词 target allocation of anti-ship missile defense area rolling optimization task re-planning
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Concurrent Two-Scale Topology Optimization of Thermoelastic Structures Using a M-VCUT Level Set Based Model of Microstructures
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作者 Jin Zhou Minjie Shao +1 位作者 Ye Tian Qi Xia 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第11期1327-1345,共19页
By analyzing the results of compliance minimization of thermoelastic structures,we observed that microstructures play an important role in this optimization problem.Then,we propose to use a multiple variable cutting(M... By analyzing the results of compliance minimization of thermoelastic structures,we observed that microstructures play an important role in this optimization problem.Then,we propose to use a multiple variable cutting(M-VCUT)level set-based model of microstructures to solve the concurrent two-scale topology optimization of thermoelastic structures.A microstructure is obtained by combining multiple virtual microstructures that are derived respectively from multiple microstructure prototypes,thus giving more diversity of microstructure and more flexibility in design optimization.The effective mechanical properties of microstructures are computed in an off-line phase by using the homogenization method,and then a mapping relationship between the design variables and the effective properties is established,which gives a data-driven model of microstructure.In the online phase,the data-driven model is used in the finite element analysis to improve the computational efficiency.The compliance minimization problem is considered,and the results of numerical examples prove that the proposed method is effective. 展开更多
关键词 Two-scale structure topology optimization multiple variable cutting level set DATA-DRIVEN radial basis function thermoelastic structure
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Optimal Multi-Timescale Scheduling of Integrated Energy Systems with Hybrid Energy Storage System Based on Lyapunov Optimization
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作者 Yehui Ma Dong Han Zhuoxin Lu 《Journal of Beijing Institute of Technology》 EI CAS 2024年第5期465-480,共16页
The economic operation of integrated energy system(IES)faces new challenges such as multi-timescale characteristics of heterogeneous energy sources,and cooperative operation of hybrid energy storage system(HESS).To th... The economic operation of integrated energy system(IES)faces new challenges such as multi-timescale characteristics of heterogeneous energy sources,and cooperative operation of hybrid energy storage system(HESS).To this end,this paper investigates the multi-timescale rolling opti-mization problem for IES integrated with HESS.Firstly,the architecture of IES with HESS is established,a comparative analysis is conducted to evaluate the advantages of the HESS over a single energy storage system(SESS)in stabilizing power fluctuations.Secondly,the dayahead and real-time scheduling cost functions of IES are established,the day-ahead scheduling mainly depends on operation costs of the components in IES,the real-time optimal scheduling adopts the Lya-punov optimization method to schedule the battery and hydrogen energy storage in each time slot,so as to minimize the real-time average scheduling operation cost,and the problem of day-ahead and real-time scheduling error,which caused by the uncertainty of the energy storage is solved by online optimization.Finally,the proposed model is verified to reduce the scheduling operation cost and the dispatching error by performing an arithmetic example analysis of the IES in Shanghai,which provides a reference for the safe and stable operation of the IES. 展开更多
关键词 integrated energy systems multiple time scales hybrid energy storage systems Lya-punov optimization
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Sequential quadratic programming-based non-cooperative target distributed hybrid processing optimization method 被引量:2
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作者 SONG Xiaocheng WANG Jiangtao +3 位作者 WANG Jun SUN Liang FENG Yanghe LI Zhi 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2023年第1期129-140,共12页
The distributed hybrid processing optimization problem of non-cooperative targets is an important research direction for future networked air-defense and anti-missile firepower systems. In this paper, the air-defense ... The distributed hybrid processing optimization problem of non-cooperative targets is an important research direction for future networked air-defense and anti-missile firepower systems. In this paper, the air-defense anti-missile targets defense problem is abstracted as a nonconvex constrained combinatorial optimization problem with the optimization objective of maximizing the degree of contribution of the processing scheme to non-cooperative targets, and the constraints mainly consider geographical conditions and anti-missile equipment resources. The grid discretization concept is used to partition the defense area into network nodes, and the overall defense strategy scheme is described as a nonlinear programming problem to solve the minimum defense cost within the maximum defense capability of the defense system network. In the solution of the minimum defense cost problem, the processing scheme, equipment coverage capability, constraints and node cost requirements are characterized, then a nonlinear mathematical model of the non-cooperative target distributed hybrid processing optimization problem is established, and a local optimal solution based on the sequential quadratic programming algorithm is constructed, and the optimal firepower processing scheme is given by using the sequential quadratic programming method containing non-convex quadratic equations and inequality constraints. Finally, the effectiveness of the proposed method is verified by simulation examples. 展开更多
关键词 non-cooperative target distributed hybrid processing multiple constraint minimum defense cost sequential quadratic programming
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Identification of time-varying system and energy-based optimization of adaptive control in seismically excited structure
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作者 Elham Aghabarari Fereidoun Amini Pedram Ghaderi 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2024年第1期227-240,共14页
The combination of structural health monitoring and vibration control is of great importance to provide components of smart structures.While synthetic algorithms have been proposed,adaptive control that is compatible ... The combination of structural health monitoring and vibration control is of great importance to provide components of smart structures.While synthetic algorithms have been proposed,adaptive control that is compatible with changing conditions still needs to be used,and time-varying systems are required to be simultaneously estimated with the application of adaptive control.In this research,the identification of structural time-varying dynamic characteristics and optimized simple adaptive control are integrated.First,reduced variations of physical parameters are estimated online using the multiple forgetting factor recursive least squares(MFRLS)method.Then,the energy from the structural vibration is simultaneously specified to optimize the control force with the identified parameters to be operational.Optimization is also performed based on the probability density function of the energy under the seismic excitation at any time.Finally,the optimal control force is obtained by the simple adaptive control(SAC)algorithm and energy coefficient.A numerical example and benchmark structure are employed to investigate the efficiency of the proposed approach.The simulation results revealed the effectiveness of the integrated online identification and optimal adaptive control in systems. 展开更多
关键词 integrated online identification time-varying systems structural energy multiple forgetting factor recursive least squares optimal simple adaptive control algorithm
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Improved cat swarm optimization for parameter estimation of mixed additive and multiplicative random error model 被引量:2
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作者 Leyang Wang Shuhao Han 《Geodesy and Geodynamics》 EI CSCD 2023年第4期385-391,共7页
To estimate the parameters of the mixed additive and multiplicative(MAM)random error model using the weighted least squares iterative algorithm that requires derivation of the complex weight array,we introduce a deriv... To estimate the parameters of the mixed additive and multiplicative(MAM)random error model using the weighted least squares iterative algorithm that requires derivation of the complex weight array,we introduce a derivative-free cat swarm optimization for parameter estimation.We embed the Powell method,which uses conjugate direction acceleration and does not need to derive the objective function,into the original cat swarm optimization to accelerate its convergence speed and search accuracy.We use the ordinary least squares,weighted least squares,original cat swarm optimization,particle swarm algorithm and improved cat swarm optimization to estimate the parameters of the straight-line fitting MAM model with lower nonlinearity and the DEM MAM model with higher nonlinearity,respectively.The experimental results show that the improved cat swarm optimization has faster convergence speed,higher search accuracy,and better stability than the original cat swarm optimization and the particle swarm algorithm.At the same time,the improved cat swarm optimization can obtain results consistent with the weighted least squares method based on the objective function only while avoiding multiple complex weight array derivations.The method in this paper provides a new idea for theoretical research on parameter estimation of MAM error models. 展开更多
关键词 Mixed additive and multiplicative random error model Parameter estimation Least squares Cat swarm optimization Powell method
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Gene signatures to therapeutics:Assessing the potential of ivermectin against t(4;14)multiple myeloma
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作者 Yang Song Hao-Jun Zhang +5 位作者 Xia Song Jie Geng Hong-Yi Li Li-Zhong Zhang Bo Yang Xue-Chun Lu 《World Journal of Clinical Oncology》 2024年第1期115-129,共15页
BACKGROUND Multiple myeloma(MM)is a terminal differentiated B-cell tumor disease characterized by clonal proliferation of malignant plasma cells and excessive levels of monoclonal immunoglobulins in the bone marrow.Th... BACKGROUND Multiple myeloma(MM)is a terminal differentiated B-cell tumor disease characterized by clonal proliferation of malignant plasma cells and excessive levels of monoclonal immunoglobulins in the bone marrow.The translocation,(t)(4;14),results in high-risk MM with limited treatment alternatives.Thus,there is an urgent need for identification and validation of potential treatments for this MM subtype.Microarray data and sequencing information from public databases could offer opportunities for the discovery of new diagnostic or therapeutic targets.AIM To elucidate the molecular basis and search for potential effective drugs of t(4;14)MM subtype by employing a comprehensive approach.METHODS The transcriptional signature of t(4;14)MM was sourced from the Gene Expression Omnibus.Two datasets,GSE16558 and GSE116294,which included 17 and 15 t(4;14)MM bone marrow samples,and five and four normal bone marrow samples,respectively.After the differentially expressed genes were identified,the Cytohubba tool was used to screen for hub genes.Then,the hub genes were analyzed using Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analysis.Using the STRING database and Cytoscape,protein–protein interaction networks and core targets were identified.Potential small-molecule drugs were identified and validated using the Connectivity Map database and molecular docking analysis,respectively.RESULTS In this study,a total of 258 differentially expressed genes with enriched functions in cancer pathways,namely cytokine receptor interactions,nuclear factor(NF)-κB signaling pathway,lipid metabolism,atherosclerosis,and Hippo signaling pathway,were identified.Ten hub genes(cd45,vcam1,ccl3,cd56,app,cd48,btk,ccr2,cybb,and cxcl12)were identified.Nine drugs,including ivermectin,deforolimus,and isoliquiritigenin,were predicted by the Connectivity Map database to have potential therapeutic effects on t(4;14)MM.In molecular docking,ivermectin showed strong binding affinity to all 10 identified targets,especially cd45 and cybb.Ivermectin inhibited t(4;14)MM cell growth via the NF-κB pathway and induced MM cell apoptosis in vitro.Furthermore,ivermectin increased reactive oxygen species accumulation and altered the mitochondrial membrane potential in t(4;14)MM cells.CONCLUSION Collectively,the findings offer valuable molecular insights for biomarker validation and potential drug development in t(4;14)MM diagnosis and treatment,with ivermectin emerging as a potential therapeutic alternative. 展开更多
关键词 multiple myeloma Functional enrichment analysis Molecular docking simulation Gene expression profiling Therapeutic target IVERMECTIN
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A Cooperative Security Monitoring Mechanism Aided by Optimal Multiple Slave Cluster Heads for UASNs
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作者 Yougan Chen Wei Wang +3 位作者 Xiang Sun Yi Tao Zhenwen Liu Xiaomei Xu 《China Communications》 SCIE CSCD 2023年第5期148-169,共22页
As each cluster head(CH)sensor node is used to aggregate,fuse,and forward data from different sensor nodes in an underwater acoustic sensor network(UASN),guaranteeing the data security in a CH is very critical.In this... As each cluster head(CH)sensor node is used to aggregate,fuse,and forward data from different sensor nodes in an underwater acoustic sensor network(UASN),guaranteeing the data security in a CH is very critical.In this paper,a cooperative security monitoring mechanism aided by multiple slave cluster heads(SCHs)is proposed to keep track of the data security of a CH.By designing a low complexity“equilateral triangle algorithm(ETA)”,the optimal SCHs(named as ETA-based multiple SCHs)are selected from the candidate SCHs so as to improve the dispersion and coverage of SCHs and achieve largescale data security monitoring.In addition,by analyzing the entire monitoring process,the close form expression of the probability of the failure attack identification for the SCHs with respect to the probability of attack launched by ordinary nodes is deduced.The simulation results show that the proposed optimal ETA-based multiple SCH cooperation scheme has lower probability of the failure attack identification than that of the existing schemes.In addition,the numerical simulation results are consistent with the theoretical analysis results,thus verifying the effectiveness of the proposed scheme. 展开更多
关键词 underwater acoustic sensor networks data security cluster head nodes optimal location distribution of multiple slave cluster head nodes
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A simulation method on target strength and circular SAS imaging of Xrudder UUV including multiple acoustic scattering
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作者 Wenhuan Wang Bin Wang +3 位作者 Jun Fan Fulin Zhou Kaiqi Zhao Zhou Jiang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第5期214-228,共15页
Target strength(TS)and circular synthetic aperture sonar(CSAS)images provide essential information for active acoustic detection and recognition of non-cooperative unmanned undersea vehicles(UUVs),which pose a signifi... Target strength(TS)and circular synthetic aperture sonar(CSAS)images provide essential information for active acoustic detection and recognition of non-cooperative unmanned undersea vehicles(UUVs),which pose a significant threat to underwater preset facilities.To access them,we propose an iterative physical acoustics(IPA)-based method to simulate the multiple acoustic scattered fields on rigid surfaces in high-frequency cases.It uses the Helmholtz integral equation with an appropriate Green's function in terms of the Neumann series,and then incorporates the ideas of triangulation and iteration into a numerical implementation.Then two approximate analytic formulae with precise physical meanings are derived to predict the TS and CSAS images of concave targets,respectively.There are no restrictions on the surface's curvature and the order of multiple scattering.The method is validated against the finite element method(FEM)for acoustic scattering from a sphere segment and against an experiment involving an X-rudder UUV's stern.On this basis,we simulate and analyze the TS and CSAS images of an X-rudder UUV.In addition,the influence of the angle of adjacent rudders on the multiple scattering characteristics is discussed.Results show that this method can potentially predict accurate UUV features,especially the multiple scattered features. 展开更多
关键词 multiple acoustic scattering target strength(TS) Circular synthetic aperture sonar(CSAS) X-rudder unmanned undersea vehicle (UUV) Iterative physical acoustics(IPA)
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Labeled box-particle CPHD filter for multiple extended targets tracking 被引量:4
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作者 ZOU Zhibin SONG Liping CHENG Xuan 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2019年第1期57-67,共11页
In multiple extended targets tracking, replacing traditional multiple measurements with a rectangular region of the nonzero volume in the state space inspired by the box-particle idea is exactly suitable to deal with ... In multiple extended targets tracking, replacing traditional multiple measurements with a rectangular region of the nonzero volume in the state space inspired by the box-particle idea is exactly suitable to deal with extended targets, without distinguishing the measurements originating from the true targets or clutter.Based on our recent work on extended box-particle probability hypothesis density(ET-BP-PHD) filter, we propose the extended labeled box-particle cardinalized probability hypothesis density(ET-LBP-CPHD) filter, which relaxes the Poisson assumptions of the extended target probability hypothesis density(PHD) filter in target numbers, and propagates not only the intensity function but also cardinality distribution. Moreover, it provides the identity of individual target by adding labels to box-particles. The proposed filter can improve the precision of estimating target number meanwhile achieve targets' tracks. The effectiveness and reliability of the proposed algorithm are verified by the simulation results. 展开更多
关键词 EXTENDED target multiple targets tracking labled boxparticle cardinalized probability HYPOTHESIS density (CPHD).
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MicroRNAs as disease progression biomarkers and therapeutic targets in experimental autoimmune encephalomyelitis model of multiple sclerosis 被引量:11
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作者 Bridget Martinez Philip V.Peplow 《Neural Regeneration Research》 SCIE CAS CSCD 2020年第10期1831-1837,共7页
Multiple sclerosis is an autoimmune neurodegenerative disease of the central nervous system characterized by pronounced inflammatory infiltrates entering the brain,spinal cord and optic nerve leading to demyelination.... Multiple sclerosis is an autoimmune neurodegenerative disease of the central nervous system characterized by pronounced inflammatory infiltrates entering the brain,spinal cord and optic nerve leading to demyelination.Focal demyelination is associated with relapsing-remitting multiple sclerosis,while progressive forms of the disease show axonal degeneration and neuronal loss.The tests currently used in the clinical diagnosis and management of multiple sclerosis have limitations due to specificity and sensitivity.MicroRNAs(miRNAs)are dysregulated in many diseases and disorders including demyelinating and neuroinflammatory diseases.A review of recent studies with the experimental autoimmune encephalomyelitis animal model(mostly female mice 6–12 weeks of age)has confirmed miRNAs as biomarkers of experimental autoimmune encephalomyelitis disease and importantly at the pre-onset(asymptomatic)stage when assessed in blood plasma and urine exosomes,and spinal cord tissue.The expression of certain miRNAs was also dysregulated at the onset and peak of disease in blood plasma and urine exosomes,brain and spinal cord tissue,and at the post-peak(chronic)stage of experimental autoimmune encephalomyelitis disease in spinal cord tissue.Therapies using miRNA mimics or inhibitors were found to delay the induction and alleviate the severity of experimental autoimmune encephalomyelitis disease.Interestingly,experimental autoimmune encephalomyelitis disease severity was reduced by overexpression of miR-146a,miR-23b,miR-497,miR-26a,and miR-20b,or by suppression of miR-182,miR-181c,miR-223,miR-155,and miR-873.Further studies are warranted on determining more fully miRNA profiles in blood plasma and urine exosomes of experimental autoimmune encephalomyelitis animals since they could serve as biomarkers of asymptomatic multiple sclerosis and disease course.Additionally,studies should be performed with male mice of a similar age,and with aged male and female mice. 展开更多
关键词 animal model blood plasma blood serum brain tissue disease biomarkers experimental autoimmune encephalomyelitis MICRORNAS multiple sclerosis spinal cord therapeutic targets urine exosomes
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Structure Optimization and Performance Analysis of a Multiple Radial Magnetorheological Valve 被引量:3
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作者 Guoliang Hu Fang Zhong +1 位作者 Haiyun Zhang Ruqi Ding 《Journal of Beijing Institute of Technology》 EI CAS 2017年第4期458-467,共10页
Due to the controllable and reversible properties of the smart magnetorheological (MR) fluid,a novel multiple radial MR valve was developed. The fluid flowchannels of the proposed MR valve were mainly composed of tw... Due to the controllable and reversible properties of the smart magnetorheological (MR) fluid,a novel multiple radial MR valve was developed. The fluid flowchannels of the proposed MR valve were mainly composed of two annular fluid flowchannels,four radial fluid flow channels and three centric pipe fluid flowchannels. The working principle of the multiple radial MR valve was introduced in detail,and the structure optimization design was carried out using ANSYS software to obtain the optimal structure parameters. Moreover,the optimized MR valve was compared with preoptimized MR valve in terms of their magnetic flux density of radial fluid resistance gap and performance of pressure drop. The experimental test rig was set up to investigate the performance of pressure drop of the proposed MR valve under different currents applied and different loading cases. The results showthat the pressure drop between the inlet and outlet port could reach 5. 77 MPa at the applied current of 0. 8 A. Furthermore,the experimental results also indicate that the loading cases had no effect on the performance of pressure drop. 展开更多
关键词 magnetorheological MR valve multiple radial flow optimization design pressure drop
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