针对6G时代空天地一体化网络架构中空基网络无人集群对时延敏感型业务提出的确定性传输需求,提出一种基于跨层优化的确定性无人集群网络协议——LPCO(link-scheduling and path-planning based on cross-layer optimization)。该协议在...针对6G时代空天地一体化网络架构中空基网络无人集群对时延敏感型业务提出的确定性传输需求,提出一种基于跨层优化的确定性无人集群网络协议——LPCO(link-scheduling and path-planning based on cross-layer optimization)。该协议在中心节点控制的集中式架构下,融合链路状态感知、业务需求感知、显式路径规划和周期时隙调度等关键模块,实现了网络层路径选择与MAC层时隙分配的联合调度,构建了端到端的跨层协同优化机制。具体方法包括:在中心控制节点完成对全网拓扑感知后,通过基于链路过期时间(link expiration time, LET)进行链路预测,利用QoS加权目标函数实现路径规划,结合TDMA对路径节点动态分配时隙,确保关键业务在无人集群网络下的低延迟传输和高可靠性。通过在NS3仿真平台中与典型路由协议OLSR和DSDV对比验证,仿真实验结果表明:LPCO相较OLSR与DSDV协议,时敏业务的平均端到端时延分别降低了43.6%、40.7%;时敏业务的分组投递率提升了69.3%、73.5%;瞬时时延抖动控制在3 ms以内,部分数据包抖动接近0,在无人集群网络中展现出确定性服务保障能力与鲁棒性。展开更多
With the development of operationally responsive space（ORS） and on-board processing techniques, the end users canreceive the observation data from the ORS satellite directly. Tosatisfy the demand for reducing the re...With the development of operationally responsive space（ORS） and on-board processing techniques, the end users canreceive the observation data from the ORS satellite directly. Tosatisfy the demand for reducing the requirements-tasking-effectscycle from one day to hours, the various resources of the wholedata acquisition chain （including satellites, ground stations, dataprocessing centers, users, etc.） should be taken into an overallconsideration, and the traditional batch task planning mode shouldbe transformed into the user-oriented task planning mode. Consideringthere are many approaches for data acquisition due tothe new techniques of ORS satellite, the data acquisition chaintask planning problem for ORS satellite can be seen as the multimodalroute planning problem. Thereby, a framework is presentedusing label-constrained shortest path technique with the conflictresolution. To apply this framework to solve the ORS satellite taskplanning problem, the preprocessing and the conflict resolutionstrategies are discussed in detail. Based on the above work, theuser-oriented data acquisition chain task planning algorithm forORS satellite is proposed. The exact solution can be obtainedin polynomial time using the proposed algorithm. The simulationexperiments validate the feasibility and the adaptability of the proposedapproach.展开更多
针对遥感图像微小目标检测中存在的浅层细化特征、深层语义表征和多尺度信息提取3个问题,提出一种综合运用多项技术的跨尺度YOLOv7(cross-scale YOLOv7,CSYOLOv7)网络。首先,设计跨阶段特征提取模块(cross-stage feature extraction mod...针对遥感图像微小目标检测中存在的浅层细化特征、深层语义表征和多尺度信息提取3个问题,提出一种综合运用多项技术的跨尺度YOLOv7(cross-scale YOLOv7,CSYOLOv7)网络。首先,设计跨阶段特征提取模块(cross-stage feature extraction module,CFEM)和感受野特征增强模块(receptive field feature enhancement module,RFFEM)。CFEM提高模型细化特征提取能力并抑制浅层下采样过程中特征的丢失,RFFEM加大网络对深层语义特征的提取力度,增强模型对目标上下文信息获取能力。其次,设计跨梯度空间金字塔池化模块(cross-gradient space pyramid pool module,CSPPM)有效融合微小目标多尺度的全局和局部特征。最后,用形状感知交并比(shape-aware intersection over union,Shape IoU)替换完全交并比(complete intersection over union,CIoU),提高模型在边界框定位任务中的精确度。实验结果表明,CSYOLOv7网络在DIOR(dataset for image object recognition)数据集和NWPU VHR-10(Northwestern Polytechnical University Very High Resolution-10)数据集上分别取得了74%和89.6%的检测精度,有效提升遥感图像微小目标的检测效果。展开更多
Based on the theories of landscape ecology, landscape eco environment in the control watershed by reservoir of Erlong Mountain in Heilongjiang Province was analyzed and assessed by using GIS technique and statistical ...Based on the theories of landscape ecology, landscape eco environment in the control watershed by reservoir of Erlong Mountain in Heilongjiang Province was analyzed and assessed by using GIS technique and statistical model of Principal Component Analysis and Spatial Cluster Analysis. It is found that 100.08km2(36%)of the total area is in the state of kilter,85.73km2(31%)of the total area is in the state of general,and 47.26km2(17%)and 15.48km2(16%)is in the relatively poor state and ideal state. According to landscape ecological structure,there are three landscape function areas being planned and designed. 1) Agricultural landscape function area: its developmental direction is tour agriculture and high benefit agriculture. 2) Eco environment protected function area:the direction of development and utilization of this region is to develop vigorously forest for soil and water conservation, and try to increase the rate of vegetation cover. 3) Forest landscape function area: rational cut and utilization of forest resources, space optimization disposal of category of forest, foster of forest and protection of wildwood will become the main development directions for this region. This study trys to provide scientific foundation for ecological restoration of the whole valley and its sustainable development.展开更多
文摘针对6G时代空天地一体化网络架构中空基网络无人集群对时延敏感型业务提出的确定性传输需求,提出一种基于跨层优化的确定性无人集群网络协议——LPCO(link-scheduling and path-planning based on cross-layer optimization)。该协议在中心节点控制的集中式架构下,融合链路状态感知、业务需求感知、显式路径规划和周期时隙调度等关键模块,实现了网络层路径选择与MAC层时隙分配的联合调度,构建了端到端的跨层协同优化机制。具体方法包括:在中心控制节点完成对全网拓扑感知后,通过基于链路过期时间(link expiration time, LET)进行链路预测,利用QoS加权目标函数实现路径规划,结合TDMA对路径节点动态分配时隙,确保关键业务在无人集群网络下的低延迟传输和高可靠性。通过在NS3仿真平台中与典型路由协议OLSR和DSDV对比验证,仿真实验结果表明:LPCO相较OLSR与DSDV协议,时敏业务的平均端到端时延分别降低了43.6%、40.7%;时敏业务的分组投递率提升了69.3%、73.5%;瞬时时延抖动控制在3 ms以内,部分数据包抖动接近0,在无人集群网络中展现出确定性服务保障能力与鲁棒性。
基金supported by the National Natural Science Foundation of China(6110118461174159)
文摘With the development of operationally responsive space（ORS） and on-board processing techniques, the end users canreceive the observation data from the ORS satellite directly. Tosatisfy the demand for reducing the requirements-tasking-effectscycle from one day to hours, the various resources of the wholedata acquisition chain （including satellites, ground stations, dataprocessing centers, users, etc.） should be taken into an overallconsideration, and the traditional batch task planning mode shouldbe transformed into the user-oriented task planning mode. Consideringthere are many approaches for data acquisition due tothe new techniques of ORS satellite, the data acquisition chaintask planning problem for ORS satellite can be seen as the multimodalroute planning problem. Thereby, a framework is presentedusing label-constrained shortest path technique with the conflictresolution. To apply this framework to solve the ORS satellite taskplanning problem, the preprocessing and the conflict resolutionstrategies are discussed in detail. Based on the above work, theuser-oriented data acquisition chain task planning algorithm forORS satellite is proposed. The exact solution can be obtainedin polynomial time using the proposed algorithm. The simulationexperiments validate the feasibility and the adaptability of the proposedapproach.
文摘针对遥感图像微小目标检测中存在的浅层细化特征、深层语义表征和多尺度信息提取3个问题,提出一种综合运用多项技术的跨尺度YOLOv7(cross-scale YOLOv7,CSYOLOv7)网络。首先,设计跨阶段特征提取模块(cross-stage feature extraction module,CFEM)和感受野特征增强模块(receptive field feature enhancement module,RFFEM)。CFEM提高模型细化特征提取能力并抑制浅层下采样过程中特征的丢失,RFFEM加大网络对深层语义特征的提取力度,增强模型对目标上下文信息获取能力。其次,设计跨梯度空间金字塔池化模块(cross-gradient space pyramid pool module,CSPPM)有效融合微小目标多尺度的全局和局部特征。最后,用形状感知交并比(shape-aware intersection over union,Shape IoU)替换完全交并比(complete intersection over union,CIoU),提高模型在边界框定位任务中的精确度。实验结果表明,CSYOLOv7网络在DIOR(dataset for image object recognition)数据集和NWPU VHR-10(Northwestern Polytechnical University Very High Resolution-10)数据集上分别取得了74%和89.6%的检测精度,有效提升遥感图像微小目标的检测效果。
文摘Based on the theories of landscape ecology, landscape eco environment in the control watershed by reservoir of Erlong Mountain in Heilongjiang Province was analyzed and assessed by using GIS technique and statistical model of Principal Component Analysis and Spatial Cluster Analysis. It is found that 100.08km2(36%)of the total area is in the state of kilter,85.73km2(31%)of the total area is in the state of general,and 47.26km2(17%)and 15.48km2(16%)is in the relatively poor state and ideal state. According to landscape ecological structure,there are three landscape function areas being planned and designed. 1) Agricultural landscape function area: its developmental direction is tour agriculture and high benefit agriculture. 2) Eco environment protected function area:the direction of development and utilization of this region is to develop vigorously forest for soil and water conservation, and try to increase the rate of vegetation cover. 3) Forest landscape function area: rational cut and utilization of forest resources, space optimization disposal of category of forest, foster of forest and protection of wildwood will become the main development directions for this region. This study trys to provide scientific foundation for ecological restoration of the whole valley and its sustainable development.
