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基于空间Shift-Share模型测度区域经济空间影响的新方法 被引量:2
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作者 董麓 李晓欣 《统计与信息论坛》 CSSCI 北大核心 2015年第5期3-9,共7页
梳理Shift-Share模型的演进过程,讨论了不同形式的Shift-Share模型的经济学含义,并将其拓展到区域空间影响测度研究,构建了一个完整的分析框架和测量模型。将该方法应用于长三角地区产业空间影响测度,得到了一些有意义的结论。
关键词 区域经济 产业空间影响 shift-share模型
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Shift-Share区域经济评价模型及其扩展研究 被引量:11
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作者 董麓 付灵芝 朱少杰 《统计与信息论坛》 CSSCI 2011年第6期9-13,共5页
讨论了Shift-Share模型的经济思想,指出现有研究反映经济信息的片面性。对Shift-Share方法进行了扩展,提出了产业结构效率新概念,并诠释了其经济思想,构造了更具经济评价和政策意义的区域产业结构分析统计模型,用具体案例介绍了模型使... 讨论了Shift-Share模型的经济思想,指出现有研究反映经济信息的片面性。对Shift-Share方法进行了扩展,提出了产业结构效率新概念,并诠释了其经济思想,构造了更具经济评价和政策意义的区域产业结构分析统计模型,用具体案例介绍了模型使用方法。 展开更多
关键词 shift-share模型 产业结构 区域经济评价
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结构变迁效应与旅游业发展潜力——基于Shift-Share方法的分析和检验 被引量:10
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作者 杨勇 《华东师范大学学报(哲学社会科学版)》 CSSCI 北大核心 2009年第5期108-113,共6页
结构变动是生产率增长的一个重要原因。使用Shift-Share方法,将旅游业潜力从产业结构变迁和要素生产率中分解出来,可以系统分析中国旅游产业结构变动和生产率增长结构,实证度量产业结构变迁对中国旅游业发展的贡献,识别和比较"结... 结构变动是生产率增长的一个重要原因。使用Shift-Share方法,将旅游业潜力从产业结构变迁和要素生产率中分解出来,可以系统分析中国旅游产业结构变动和生产率增长结构,实证度量产业结构变迁对中国旅游业发展的贡献,识别和比较"结构红利"中旅游业潜力的形成和动态变迁机制,从"结构红利"角度解释旅游业潜力的来源、形成及其对旅游业发展的影响。研究表明,旅游产业结构变迁对我国部分省份的影响比较显著,显示出较高的旅游业发展潜力和发展表现,但是,对于另外一部分省份来说,基于产业结构变迁视角的旅游业潜力并未出现,这也影响了其旅游业劳动生产率的提升和发展。 展开更多
关键词 旅游业 结构变迁 劳动生产率 shift-share方法
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长江中游农业产业增长与结构贡献——基于Shift-Share模型 被引量:3
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作者 黄玛兰 李晓云 +1 位作者 刘念 袁梦烨 《农业展望》 2017年第9期69-75,共7页
利用1980—2014年的统计数据,以长江经济带为标准区域,运用动态Shift-Share模型分析了长江中游农业产业结构的发展优势与劣势及四省农业总产值增长的差异。结果表明,1980—2014年长江中游农业总产值增长优势高于长江经济带农业总产值平... 利用1980—2014年的统计数据,以长江经济带为标准区域,运用动态Shift-Share模型分析了长江中游农业产业结构的发展优势与劣势及四省农业总产值增长的差异。结果表明,1980—2014年长江中游农业总产值增长优势高于长江经济带农业总产值平均增长水平。长江中游农业产业结构变化对长江经济带农业发展的影响分为:湖北、湖南农业产业结构偏离<0,竞争力偏离>0;江西农业产业结构偏离>0,竞争力偏离<0;安徽农业产业结构偏离<0,竞争力偏离<0等3种类型。为进一步提高长江经济带农业产业总体发展水平,各省应充分发挥比较优势,引导农业生产合理布局,提高农业资源的配置及利用效率。 展开更多
关键词 长江中游 长江经济带 农业产业结构 竞争力与结构优势 shift-share模型
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A near-infrared all-fiber mode monitor based on the mini-two-path Mach-Zehnder interferometer
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作者 ZHU Xiao-Jun LIU Yu +5 位作者 WU Yue ZHUANG Hao-Ran SUN Dan SHI Yue-Chun CAO Juan YANG Yong-Jie 《红外与毫米波学报》 北大核心 2025年第3期352-357,共6页
A novel near-infrared all-fiber mode monitor based on a mini-two-path Mach-Zehnder interferometer(MTP-MZI)is proposed.The MTP-MZI mode monitor is created by fusing a section of(no-core fiber,NCF)and a(single-mode fibe... A novel near-infrared all-fiber mode monitor based on a mini-two-path Mach-Zehnder interferometer(MTP-MZI)is proposed.The MTP-MZI mode monitor is created by fusing a section of(no-core fiber,NCF)and a(single-mode fiber,SMF)together with an optical fiber fusion splicer,establishing two distinct centimeter-level optical transmission paths.Since the high-order modes in NCF transmit near-infrared light more sensitively to curvature-induced energy leakage than the fundamental mode in SMF,the near-infrared high-order mode light leaks out of NCF when the curvature changes,causing the MTP-MZI transmission spectrum to change.By ana⁃lyzing the relationship between the curvature,transmission spectrum,and spatial frequency spectrum,the modes involved in the interference can be studied,thereby revealing the mode transmission characteristics of near-infra⁃red light in optical fibers.In the verification experiments,higher-order modes were excited by inserting a novel hollow-core fiber(HCF)into the MTP-MZI.When the curvature of the MTP-MZI changes,the near-infrared light high-order mode introduced into the device leaks out,causing the transmission spectrum to return to its origi⁃nal state before bending and before the HCF was spliced.The experimental results demonstrate that the MTP-MZI mode monitor can monitor the fiber modes introduced from the external environment,providing both theoretical and experimental foundations for near-infrared all-fiber mode monitoring in optical information systems. 展开更多
关键词 near-infrared mode monitor Mach-Zehnder interferometer two-path structure all-fiber-format
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Accidental zero modes in a multiorbital superconductor with spin-orbital coupling
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作者 XIANG Ke WANG Da WANG Qianghua 《物理学进展》 北大核心 2025年第5期250-259,共10页
The Majorana zero modes in vortex cores are of extensive interest in the context of topological quantum computing.However,a zero-energy bound state may arise accidentally but is not necessarily a Majorana zero mode.Su... The Majorana zero modes in vortex cores are of extensive interest in the context of topological quantum computing.However,a zero-energy bound state may arise accidentally but is not necessarily a Majorana zero mode.Such accidental zero modes should be carefully ruled out in experiment in order to identify the genuine Majorana zero modes.We show that in a spin-orbital coupled multi-band superconductor,such as the iron-selenide superconductor,accidental zero modes indeed arise in the vortex core if the pairing symmetry is the so-called nodeless d-wave(defined in the absence of spin-orbital coupling).Instead,if the pairing sym-metry is s_(++)or s_(+−)with respect to the Fermi pockets split by the spin-orbital coupling,the accidental zero modes do not appear in the limit of weak spin-orbital coupling.Our results are not only important in the experimental identification of Majorana zero modes,but also provide an avenue to pinpoint the pairing symmetry of the iron-selenide superconductor. 展开更多
关键词 spin-orbital coupling Andreev approximation accidental zero mode
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Investigation on the Ice Load on a Cylinder Vertically Breaking through Model Ice Sheet from Underneath
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作者 ZHAO Wei−hang TIAN Yu−kui +3 位作者 JI Shao−peng GANG Xu−hao YU Chao−ge KONG Shuai 《船舶力学》 北大核心 2025年第6期964-975,共12页
Ice load on underwater vehicles breaking through ice covers from underneath is a significant concern for researchers in polar exploration,and the research on this problem is still in its early stages.Both mechanical e... Ice load on underwater vehicles breaking through ice covers from underneath is a significant concern for researchers in polar exploration,and the research on this problem is still in its early stages.Both mechanical experimental measurement and numerical simulation pose research challenges.This study focuses on the ice load of a cylinder structure breaking upward through the ice sheet form underneath in the Small Ice Model Basin of China Ship Scientific Research Center(CSSRC SIMB).A high-speed camera system was employed to observe the ice sheet failure during the tests,in which,with the loading position as center,local radial cracks and circumferential cracks were generated.A load sensor was used to measure the overall ice load during this process.Meanwhile,a numerical model was developed using LS-DYNA for validation and comparison.With this model,numerical simulation was conducted under various ice thicknesses and upgoing speeds to analyze the instantaneous curves of ice load.The calculation results were statistically analyzed under different working conditions to determine the influence of the factors on the ice load of the cylinder.The study explores the measurement method about ice load of objects vertically breaking through model ice sheet and is expected to provide some fundamental insights into the safety design of underwater structures operating in ice waters. 展开更多
关键词 CYLINDER model test failure mode crack propagation ice load numerical modeling
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Fault-tolerant control for diesel engine air path system via sliding mode surface
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作者 WU Wen-jie ZHANG Yi-xin +4 位作者 WANG Xing-jian WANG Shao-ping ZHANG Jian ZHENG Wei TAO Mo 《控制理论与应用》 北大核心 2025年第8期1570-1577,共8页
The operating environment of the diesel engine air path system is complex and may be affected by external random disturbances.Potentially leading to faults.This paper addresses the fault-tolerant control problem of th... The operating environment of the diesel engine air path system is complex and may be affected by external random disturbances.Potentially leading to faults.This paper addresses the fault-tolerant control problem of the diesel engine air path system,assuming that the system may simultaneously be affected by actuator faults and external random disturbances,a disturbance observer-based sliding mode controller is designed.Through the linear matrix inequality technique for solving observer and controller gains,optimal gain matrices can be obtained,eliminating the manual adjustment process of controller parameters and reducing the chattering phenomenon of the sliding mode surface.Finally,the effectiveness of the proposed method is verified through simulation analysis. 展开更多
关键词 disel engine air path fault-tolerant control sliding mode control disturbance observer
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Modeling and sliding mode control based on inverse compensation of piezo-positioning system
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作者 LI Zhi-bin XIN Yuan-ze +1 位作者 ZHANG Jian-qiang SUN Chong-shang 《中国光学(中英文)》 北大核心 2025年第1期170-185,共16页
In order to enhance the control performance of piezo-positioning system,the influence of hysteresis characteristics and its compensation method are studied.Hammerstein model is used to represent the dynamic hysteresis... In order to enhance the control performance of piezo-positioning system,the influence of hysteresis characteristics and its compensation method are studied.Hammerstein model is used to represent the dynamic hysteresis nonlinear characteristics of piezo-positioning actuator.The static nonlinear part and dynamic linear part of the Hammerstein model are represented by models obtained through the Prandtl-Ishlinskii(PI)model and Hankel matrix system identification method,respectively.This model demonstrates good generalization capability for typical input frequencies below 200 Hz.A sliding mode inverse compensation tracking control strategy based on P-I inverse model and integral augmentation is proposed.Experimental results show that compared with PID inverse compensation control and sliding mode control without inverse compensation,the sliding mode inverse compensation control has a more ideal step response and no overshoot,moreover,the settling time is only 6.2 ms.In the frequency domain,the system closed-loop tracking bandwidth reaches 119.9 Hz,and the disturbance rejection bandwidth reaches 86.2 Hz.The proposed control strategy can effectively compensate the hysteresis nonlinearity,and improve the tracking accuracy and antidisturbance capability of piezo-positioning system. 展开更多
关键词 piezo-positioning system hysteresis nonlinearity Hammerstein model Prandtl-Ishlinskii(P-I)model system identification sliding mode control
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Design and implementation of disturbance sliding mode observer for enhancing the dynamic control precision of inertial stabilization platform
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作者 ZHANG Zhidong YANG Gongliu +2 位作者 CAI Qingzhong FAN Jing LI Tao 《Journal of Systems Engineering and Electronics》 2025年第3期791-802,共12页
In order to enhance the dynamic control precision of inertial stabilization platform(ISP),a disturbance sliding mode observer(DSMO)is proposed in this paper suppressing disturbance torques inherent within the system.T... In order to enhance the dynamic control precision of inertial stabilization platform(ISP),a disturbance sliding mode observer(DSMO)is proposed in this paper suppressing disturbance torques inherent within the system.The control accuracy of ISP is fundamentally circumscribed by various disturbance torques in rotating shaft.Therefore,a dynamic model of ISP incorporating composite perturbations is established with regard to the stabilization of axis in the inertial reference frame.Subsequently,an online estimator for control loop uncertainties based on the sliding mode control algorithm is designed to estimate the aggregate disturbances of various parameters uncertainties and other unmodeled disturbances that cannot be accurately calibrated.Finally,the proposed DSMO is integrated into a classical proportional-integral-derivative(PID)control scheme,utilizing feedforward approach to compensate the composite disturbance in the control loop online.The effectiveness of the proposed disturbance observer is validated through simulation and hardware experimentation,demonstrating a significant improvement in the dynamic control performance and robustness of the classical PID controller extensively utilized in the field of engineering. 展开更多
关键词 inertial stabilization platform disturbance suppression sliding mode observer robust control
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Cross-platform mission planning for UAVs under carrier delivery mode
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作者 Junhong Jin Genlai Zhang +6 位作者 Xin Li Xichao Su Chen Lu Yujie Cheng Yu Ding Lei Wang Xinwei Wang 《Defence Technology(防务技术)》 2025年第11期76-97,共22页
As battlefield scale enlarges,cross-platform collaborative combat provides an appealing paradigm for modern warfare.Complicated constraints and vast solution space pose great challenge for reasonable and efficient mis... As battlefield scale enlarges,cross-platform collaborative combat provides an appealing paradigm for modern warfare.Complicated constraints and vast solution space pose great challenge for reasonable and efficient mission planning,where path planning and target assignment are tightly coupled.In this paper,we focus on UAV mission planning under carrier delivery mode(e.g.,by aircraft carrier,ground vehicle,or transport aircraft) and design a three-layer hierarchical solution framework.In the first layer,we simultaneously determine delivery points and target set division by clustering.To address the safety concerns of radar risk and UAV endurance,an improved density peak clustering algorithm is developed by constraint fusio n.In the second layer,mission planning within each cluster is viewed as a coope rative multiple-task assignment problem.A hybrid heuristic algorithm that integrates a voting-based heuristic solution generation strategy(VHSG) and a stochastic variable neighborhood search(SVNS),called VHSG-SVNS,is proposed for rapid solution.Based on the results of the first two layers,the third layer transforms carrier path planning into a multiple-vehicle routing problem with time window.The cost between any two nodes is calculated by the A~* algorithm,and the genetic algorithm is then implemented to determine the global route.Finally,a practical mission scenario containing 200 targets is used to validate the effectiveness of the designed framework,where three layers cooperate well with each other to generate satisfactory combat scheduling.Comparisons are made in each layer to highlight optimum-seeking capability and efficiency of the proposed algorithms.Works done in this paper provide a simple but efficient solution framework for cross-platform cooperative mission planning problems,and can be potentially extended to other applications such as post-disaster search and rescue,forest surveillance and firefighting,logistics pick and delivery,etc. 展开更多
关键词 Cross-platform mission planning UAV Carrier delivery mode Clustering algorithm Heuristic optimization algorithm
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Failure modes and transformation laws of reinforced concrete slabs under drop hammer impact
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作者 Chunming Song Jiahe Zhong +3 位作者 Haotian Zhang Yuetang Zhao Zhongwei Zhang Feng Liu 《Defence Technology(防务技术)》 2025年第9期318-339,共22页
With the change of the main influencing factors such as structural configuration and impact conditions,reinforced concrete slabs exhibit different mechanical behaviors with different failure patterns,and the failure m... With the change of the main influencing factors such as structural configuration and impact conditions,reinforced concrete slabs exhibit different mechanical behaviors with different failure patterns,and the failure modes are transformed.In order to reveal the failure mode and transformation rule of reinforced concrete slabs under impact loads,a dynamic impact response test was carried out using a drop hammer test device.The dynamic data pertaining to the impact force,support reaction force,structural displacement,and reinforcement strain were obtained through the use of digital image correlation technology(DIC),impact force measurement,and strain measurement.The analysis of the ultimate damage state of the reinforced concrete slab identified four distinct types of impact failure modes:local failure by stamping,overall failure by stamping,local-overall coupling failure,and local failure by punching.Additionally,the influence laws of hammerhead shape,hammer height,and reinforcement ratio on the dynamic response and failure mode transformation of the slab were revealed.The results indicate that:(1)The local damage to the slab by the plane hammer is readily apparent,while the overall damage by the spherical hammer is more pronounced.(2)In comparison to the high reinforcement ratio slabs,the overall bending resistance of the low reinforcement ratio slabs is significantly inferior,and the slab back exhibits further cracks.(3)As the hammer height increases,the slab failure mode undergoes a transformation,shifting from local failure by stamping and overall failure by stamping to local-overall coupling failure and local failure by punching.(4)Three failure mode thresholds have been established,and by comparing the peak impact force with the failure thresholds,the failure mode of the slab can be effectively determined. 展开更多
关键词 Reinforced concrete slab Drop hammer impact test Dynamic response Crack propagation Failure mode
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Non-singular fast terminal sliding mode control for roll-pitch seeker based on extended state observers
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作者 XIAO Bowen XIA Qunli 《Journal of Systems Engineering and Electronics》 2025年第2期537-551,共15页
For air-to-air missiles, the terminal guidance’s preci-sion is directly contingent upon the tracking capabilities of the roll-pitch seeker. This paper presents a combined non-singular fast terminal sliding mode contr... For air-to-air missiles, the terminal guidance’s preci-sion is directly contingent upon the tracking capabilities of the roll-pitch seeker. This paper presents a combined non-singular fast terminal sliding mode control method, aimed at resolving the frame control problem of roll-pitch seeker tracking high maneu-vering target. The sliding mode surface is structured around the principle of segmentation, which enables the control system’s rapid attainment of the zero point and ensure global fast conver-gence. The system’s state is more swiftly converged to the slid-ing mode surface through an improved adaptive fast dual power reaching law. Utilizing an extended state observer, the overall disturbance is both identified and compensated. The validation of the system’s stability and its convergence within a finite-time is grounded in Lyapunov’s stability criteria. The performance of the introduced control method is confirmed through roll-pitch seeker tracking control simulation. Data analysis reveals that newly proposed control technique significantly outperforms existing sliding mode control methods by rapidly converging the frame to the target angle, reduce the tracking error of the detec-tor for the target, and bolster tracking precision of the roll-pitch seeker huring disturbed conditions. 展开更多
关键词 air-to-air missile roll-pitch seeker finite-time con-vergence combined sliding mode control extended state observer
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A diagnosis method based on graph neural networks embedded with multirelationships of intrinsic mode functions for multiple mechanical faults
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作者 Bin Wang Manyi Wang +3 位作者 Yadong Xu Liangkuan Wang Shiyu Chen Xuanshi Chen 《Defence Technology(防务技术)》 2025年第8期364-373,共10页
Fault diagnosis occupies a pivotal position within the domain of machine and equipment management.Existing methods,however,often exhibit limitations in their scope of application,typically focusing on specific types o... Fault diagnosis occupies a pivotal position within the domain of machine and equipment management.Existing methods,however,often exhibit limitations in their scope of application,typically focusing on specific types of signals or faults in individual mechanical components while being constrained by data types and inherent characteristics.To address the limitations of existing methods,we propose a fault diagnosis method based on graph neural networks(GNNs)embedded with multirelationships of intrinsic mode functions(MIMF).The approach introduces a novel graph topological structure constructed from the features of intrinsic mode functions(IMFs)of monitored signals and their multirelationships.Additionally,a graph-level based fault diagnosis network model is designed to enhance feature learning capabilities for graph samples and enable flexible application across diverse signal sources and devices.Experimental validation with datasets including independent vibration signals for gear fault detection,mixed vibration signals for concurrent gear and bearing faults,and pressure signals for hydraulic cylinder leakage characterization demonstrates the model's adaptability and superior diagnostic accuracy across various types of signals and mechanical systems. 展开更多
关键词 Fault diagnosis Graph neural networks Graph topological structure Intrinsic mode functions Feature learning
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Modeling and analysis of maneuver laws based on higher order multi-resolution dynamic mode decomposition for hypersonic glide vehicles
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作者 Zichu Liu Yudong Hu +2 位作者 Changsheng Gao Wuxing Jing Xudong Ji 《Defence Technology(防务技术)》 2025年第6期34-47,共14页
The precise characterization of hypersonic glide vehicle(HGV) maneuver laws in complex flight scenarios still faces challenges. Non-stationary changes in flight state due to abrupt changes in maneuver modes place high... The precise characterization of hypersonic glide vehicle(HGV) maneuver laws in complex flight scenarios still faces challenges. Non-stationary changes in flight state due to abrupt changes in maneuver modes place high demands on the accuracy of modeling methods. To address this issue, a novel maneuver laws modeling and analysis method based on higher order multi-resolution dynamic mode decomposition(HMDMD) is proposed in this work. A joint time-space-frequency decomposition of the vehicle's state sequence in the complex flight scenario is achieved with the higher order Koopman assumption and standard multi-resolution dynamic mode decomposition, and an approximate dynamic model is established. The maneuver laws can be reconstructed and analyzed with extracted multi-scale spatiotemporal modes with clear physical meaning. Based on the dynamic model of HGV, two flight scenarios are established with constant angle of attack and complex maneuver laws, respectively. Simulation results demonstrate that the maneuver laws obtained using the HMDMD method are highly consistent with those derived from the real dynamic model, the modeling accuracy is better than other common modeling methods, and the method has strong interpretability. 展开更多
关键词 Hypersonic glide vehicle Dynamic mode decomposition Higher order koopman assumption Manoeuvre law modeling INTERPRETABILITY
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基于批次拆分机制的IMODE算法求解成品卷烟生产调度问题
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作者 安裕强 张源 +1 位作者 邹平 陶翼飞 《中国机械工程》 北大核心 2025年第8期1893-1903,共11页
针对成品卷烟生产调度问题,结合卷烟企业生产实际,以承担成品卷烟生产任务的卷包车间为研究对象,将其转换为异构并行机分批调度问题,以卷包机组的总切换次数和同停综合评价时间为目标建立符合成品卷烟生产工况的仿真优化模型,并设计一... 针对成品卷烟生产调度问题,结合卷烟企业生产实际,以承担成品卷烟生产任务的卷包车间为研究对象,将其转换为异构并行机分批调度问题,以卷包机组的总切换次数和同停综合评价时间为目标建立符合成品卷烟生产工况的仿真优化模型,并设计一种基于批次拆分机制的改进多目标差分进化(IMODE)算法进行求解。为满足分批生产特点,该算法采用一种不规则的矩阵编码方式表示可行解,基于反向批次学习策略生成初始种群,通过矩阵向量间的差分运算更新种群个体,采用批次拆分机制详细划分批次批量,并对子代个体进行邻域搜索,在选择操作中引入改进精英保留策略,以提高算法的寻优能力。最后基于不同订单量和车间规模的卷烟企业生产实例进行实验对比,验证了IMODE算法的性能及其在解决成品卷烟生产调度问题上的有效性。 展开更多
关键词 异构并行机 批次拆分 总切换次数 同停综合评价时间 多目标差分进化算法
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MODE方法在降水预报检验中的应用分析 被引量:40
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作者 尤凤春 王国荣 +1 位作者 郭锐 魏东 《气象》 CSCD 北大核心 2011年第12期1498-1503,共6页
采用WRF模式MET检验包中MODE方法,对BJ-RUC降水预报产品进行客观检验。使用2008—2009年汛期北京自动站逐小时降水数据,挑选出2个及以上站3小时累计降水≥50 mm的局地强降水个例及主要降水时段,根据其环流形势及影响系统进行分型,并将... 采用WRF模式MET检验包中MODE方法,对BJ-RUC降水预报产品进行客观检验。使用2008—2009年汛期北京自动站逐小时降水数据,挑选出2个及以上站3小时累计降水≥50 mm的局地强降水个例及主要降水时段,根据其环流形势及影响系统进行分型,并将其归纳出三种型:西来槽型、低涡型、切变线型。分别针对这三种型中强降水个例的主要降水时段进行检验。在检验中使用BJ-RUC模式降水预报产品,实况数据使用与强降水时段相对应的雷达QPE降水估计产品。检验结果表明,BJ-RUC模式降水漏报比空报造成的误差更为明显,对移动较明显的西来槽型降水预报能力较差,相似度评分与TS评分没有本质区别,但它能给模式应用和模式开发人员提供更多有用信息。此项工作能为该模式应用及模式改进提供参考依据。 展开更多
关键词 mode方法 RUC降水 检验 环流形势 分型
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西方体制Mark XIIA的Mode5数据格式分析 被引量:18
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作者 谭源泉 李胜强 王厚军 《电子科技大学学报》 EI CAS CSCD 北大核心 2011年第4期532-536,共5页
Mark XIIA是北约盟军统一研制的新型敌我识别系统,该系统的核心是Mode 5敌我识别。该文概述了Mark XIIA敌我识别系统的发展和系统组成,总结了Mode 5的4级工作模式,表明Mode 5不仅能完成基本的敌我识别功能,并具有态势感知、数据传输等功... Mark XIIA是北约盟军统一研制的新型敌我识别系统,该系统的核心是Mode 5敌我识别。该文概述了Mark XIIA敌我识别系统的发展和系统组成,总结了Mode 5的4级工作模式,表明Mode 5不仅能完成基本的敌我识别功能,并具有态势感知、数据传输等功能;其次从安全性、数据容量、系统可靠性3个方面详细分析了Mode 5 Level 1和Level 2的数据格式特征,指出了Mode 5 Level 1和Level 2询问应答数据中的加解密数据段;最后,总结了Mode 5 IFF系统的特点。 展开更多
关键词 加密 纠错码 敌我识别 mode5 扩频
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基于MODE方法的日本细网格模式降水预报的诊断分析 被引量:29
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作者 薛春芳 潘留杰 《高原气象》 CSCD 北大核心 2016年第2期406-418,共13页
利用CMORPH卫星与中国30000余个自动站逐时降水融合资料,基于面向对象模式诊断分析MODE方法研究了降水对象的客观表现以及日本细网格模式对2012-2013年中国34个降水个例的预报能力,并与传统TS、ETS检验方法进行了对比分析。结果表明:模... 利用CMORPH卫星与中国30000余个自动站逐时降水融合资料,基于面向对象模式诊断分析MODE方法研究了降水对象的客观表现以及日本细网格模式对2012-2013年中国34个降水个例的预报能力,并与传统TS、ETS检验方法进行了对比分析。结果表明:模式整体上能较好地捕获降水对象,但不同卷积半径下对象的个数及特征差异明显;模式对局地性或弱降水事件预报偏多(偏大),对区域性或强降水事件预报偏少(偏弱);模式较好地反映不同卷积半径下,降水对象在10 mm左右识别对象的面积、数量的变化特性,不足之处在于模式的固定阈值更为集中,识别对象的数量减少幅度偏快;采用较大半径进行卷积,有助于强降水区域的形态判定,在不同量级降水情况下存在提高收益函数的合适的卷积半径;中、低纬降水预报的总收益整体优于高纬,但不同属性呈现较大差异,具体而言,高纬地区降水强度预报更为合理,而低纬降水面积预报优于高纬;与传统TS、ETS检验相比,MODE方法受气候概率影响较小,其检验结果更加客观、多样。 展开更多
关键词 细网格模式 mode方法 卷积 技巧评分
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MARK XIIA Mode 5系统仿真及抗干扰性能分析 被引量:5
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作者 邱宏坤 杨建波 毛虎 《火力与指挥控制》 CSCD 北大核心 2011年第10期104-106,共3页
Mark XIIA Mode 5是美军及北约盟军用以提高态势感知能力的新型敌我识别系统。以其为研究对象,首先分析了它所应用的关键技术,如RS纠错编码、软扩频和MSK调制等新技术;其次根据所应用的关键技术对系统进行了模型构建,并以Matlab为仿真... Mark XIIA Mode 5是美军及北约盟军用以提高态势感知能力的新型敌我识别系统。以其为研究对象,首先分析了它所应用的关键技术,如RS纠错编码、软扩频和MSK调制等新技术;其次根据所应用的关键技术对系统进行了模型构建,并以Matlab为仿真平台进行了仿真,得出了询问/应答信号的时域波形及频谱;最后,重点对系统的抗干扰性能进行了分析,分别得出了MSK解调后、解扩后和RS解码后的误码率曲线,可以看出Mark XIIA Mode 5具有很强的抗干扰性能。 展开更多
关键词 敌我识别 mode 5 系统仿真 抗干扰
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