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施磷对灌耕风沙土磷含量及形态的影响

西北农林科技大学学报（自然科学版） 2022年第11期50卷 145-154页

作者：王雪艳王宇莹龚会蝶涂永峰宋海英何强颜杰陈波浪盛建东新疆农业大学资源与环境学院新疆土壤与植物生态过程重点实验室新疆乌鲁木齐830052 新疆慧尔农业集团股份有限公司新疆昌吉831100

【目的】探究不同磷肥品种及施用方式对灌耕风沙土磷素形态及有效性的影响,为不同磷肥在土壤中的合理施用提供理论依据。【方法】利用灌耕风沙土进行为期120 d的室内土壤培养试验,试验共设6个处理,分别为不施磷肥对照(CK)、重过磷酸钙基... 详细信息

【目的】探究不同磷肥品种及施用方式对灌耕风沙土磷素形态及有效性的影响,为不同磷肥在土壤中的合理施用提供理论依据。【方法】利用灌耕风沙土进行为期120 d的室内土壤培养试验,试验共设6个处理,分别为不施磷肥对照(CK)、重过磷酸钙基施(TSP)、磷酸一铵基施(MAP-B)、聚磷酸铵基施(APP-B)、磷酸一铵滴施(MAP-D)和聚磷酸铵滴施(APP-D),分别测定不同处理土壤有效磷和各形态无机磷的含量,并分析120 d时土壤有效磷与各形态无机磷含量的相关性。【结果】在0~5 cm土层,磷肥滴施处理(MAP-D、APP-D)的土壤有效磷含量显著高于其他处理;而在5~10和10~20 cm土层,磷肥基施处理(TSP、MAP-B和APP-B)的土壤有效磷含量显著高于其他处理(P<0.05)。与CK和APP-D处理相比,TSP、MAP-B和APP-B处理均显著增加了0~20 cm土层有效磷含量,但这3种磷肥处理间无显著差异。与CK相比,施磷处理均能不同程度地增加各土层土壤无机磷总量。0~5 cm土层MAP-D和APP-D处理无机磷总量显著高于5~10和10~20 cm土层,而TSP、MAP-B和APP-B处理对0~20 cm土层土壤的无机磷总量无显著影响。磷肥滴施处理下,Ca_(2)-P、Ca_(8)-P和Al-P的比例随土层深度的增加而降低,而磷肥基施处理能显著提高耕层土壤中Ca_(8)-P和Al-P的比例。在0~5 cm土层,土壤有效磷含量与Ca_(2)-P、Ca_(8)-P、Al-P和Ca_(10)-P含量之间呈显著的正相关关系(P<0.05);在5~10和10~20 cm土层,土壤有效磷含量与Ca_(2)-P、Al-P和Fe-P含量之间呈显著的正相关关系(P<0.05)。【结论】在本试验土壤条件下,磷肥滴施处理后仅能显著提高0~5 cm土层土壤有效磷含量,而磷肥基施处理可以提高整个耕层(0~20 cm)土壤中的有效磷含量,建议滴灌棉田通过基施价格相对较低的重过磷酸钙,可以人为扩展磷肥在土壤中的分布深度。

关键词：磷肥品种施磷方式有效磷无机磷形态风沙土

典型盐渍化土壤光谱特征及土壤含盐量反演建模

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农业网络信息 2013年第6期 20-25页

作者：朱高飞盛建东范燕敏武红旗付彦博新疆农业大学草业与环境科学学院新疆乌鲁木齐830052

针对目前干旱半干旱区存在的土壤盐渍化问题,以北疆典型盐渍化地区玛纳斯县北五岔镇为研究区,对土壤样品总盐含量及其光谱反射率进行测量。通过对土壤光谱曲线进行去包络线和一阶微分处理,分析了土壤光谱反射率曲线与土壤盐渍化程度之... 详细信息

针对目前干旱半干旱区存在的土壤盐渍化问题,以北疆典型盐渍化地区玛纳斯县北五岔镇为研究区,对土壤样品总盐含量及其光谱反射率进行测量。通过对土壤光谱曲线进行去包络线和一阶微分处理,分析了土壤光谱反射率曲线与土壤盐渍化程度之间的关系,确定了反映盐渍化程度较为敏感的波段347～377nm和1800～1911nm,并建立了高光谱定量预测模型,该模型可用于土壤盐渍化程度评价。研究结果对在干旱半干旱区高光谱数据反演土壤含盐量提供参考依据。

关键词：盐渍化土壤盐分光谱特征

Coverage enhancement for 6G satellite-terrestrial integrated networks: performance metrics, constellation configuration and resource allocation

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Science China(Information Sciences) 2023年第3期66卷 40-59页

作者： Min sheng Di ZHOU Weigang BAI Junyu LIU Haoran LI Yan SHI jiandong LI State Key Laboratory of Integrated Service Networks Xidian University Department of Broadband Communication Peng Cheng Laboratory

Since the base station-centric wireless coverage mode of 5G is difficult to support future stereoscopic global wireless coverage demands, the future infrastructure of 6G satellite-terrestrial integrated network(STIN) with mega constellations will extend from the terrestrial network to the integrated satellite-terrestrial architecture, so as to realize the improvement of wireless coverage capability through extending the spatial and temporal coverage. However, what are the specific quantitative indicators of wireless coverage? What is the basis for the effect of network configuration with mega constellations on coverage performance? How to form non-uniform coverage through intelligent resource scheduling to match non-uniformly distributed service requirements in the future 6G STIN? The aforementioned unknown fundamental problems have become a bottleneck restricting the further development of coverage expansion in the future 6G STIN. In this paper,we start with the evolution route of wireless coverage and the vision of 6G coverage and propose coverage performance evaluation metrics in 6G STINs from the perspective of signal coverage, capacity coverage, and service coverage. Furthermore, we investigate the relationship between coverage structure and coverage capability in 6G STINs with mega constellations and we find network structure characteristics suitable for 6G non-uniform service requirements, thus guiding constellation design in 6G STINs by analyzing and comparing the coverage performance of several typical mega constellations. Afterwards, we explore the application of artificial intelligence in resource collaboration to provide technology reference to enhance coverage capability for dynamic 6G service demands. Finally, we analyze possible technical challenges for improving service coverage performance in 6G STINs to provide researchers with new ideas.

关键词： 6G satellite-terrestrial integrated networks on-demand wireless coverage performance metrics constellation configuration intelligent resource scheduling

Reinforcement Learning-Based Handover Strategy for Space-Ground Integration Network with Large-scale Constellations

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Journal of Communications and Information Networks 2022年第4期7卷 421-432页

作者： Xiao Jia Di Zhou Min sheng Yan Shi Ningyuan Wang jiandong Li State Key Laboratory of Integrated Service Networks Xidian UniversityXi’an 710071China Institute of Telecommunication and Navigation Satellites China Academy of Space TechnologyBeijing 100000Chin

The space-ground integration network(SGIN)with large-scale constellations has become an important topic of the next generation mobile communication technology,in which the handover technology between the satellite and the ground is the key technology to ensure the continuity of user ***,compared with the ground base station’s coverage of users,satellites have larger coverage and propagation delay,and large-scale constellations make multiple selectable service satellites above the same *** phenomena bring great challenges to the handover *** paper designs a reinforcement learning-based multi-attribute satellite-ground handover strategy(RLMSGHS)for SGIN with large-scale ***,users are clustered with the attributes of location,speed,and bandwidth ***,the handover decision can be made based on the proposed RLMSGHS according to the attributes of received signal strength(RSS),speed,network bandwidth utilization and,handover ***,the simulation results demonstrate that the heavy decision-making burden caused by the large-scale growth of users in the SGIN is significantly *** multi-attribute handover decision in the SGIN is realized,which reduces the handover demand of users and improves the resource utilization rate of the SGIN.

关键词： SGIN large-scale constellations satelliteground handover cluster reinforcement learning

Concurrent Reconfiguration of Resource-Oriented Emergency TT&C Mission Planning for Space Information Networks

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Journal of Communications and Information Networks 2021年第2期6卷 142-152页

作者： Yixin Wang Di Zhou Ningbo Song Min sheng jiandong Li Jianping Liu The State Key Laboratory of Integrated Service Networks Xidian UniversityXi'anShaanxi 710071China The State Key Laboratory of Astronautic Dynamic Xi'an Satellite control centerXi'anShaanxi 710043China

The scale expansion of the space information networks(SINs)makes the demands for tacking,telemetry and command(TT&C)missions increase *** increasing number of missions and a sharp conflict of resources make it much more challenging to schedule missions *** order to ensure both the mission completion rate of the high concurrent emergency missions and the performance of regular missions,a conflict degree scheduling algorithm based on transfer strategy(CDSA-TS)is proposed concurrently reconfiguring multi-dimensional resources ***,we design an emergency mission planning algorithm based on simulated annealing algorithm(EMPA-SA)to increase the probability of jumping out of the trap through the iterative neighborhood searching strategy and ***,we design a simulation system to verify the network performance in terms of the integrated weights of completed missions and the time consumption of the proposed *** also investigate the impact of the scheduling strategy for emergency missions on regular missions to improve the overall network performance,which provides guidance for emergency mission planning in the future for the large scale constellation oriented SINs.

关键词： space information networks concurrent re-configuration of multi-dimensional resources TT&C missions simulated annealing emergency mission planning

A novel distributed algorithm for media access control address assignment in wireless sensor networks

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Frontiers of Electrical and Electronic Engineering in China 2007年第4期2卷 459-463页

作者： TIAN Ye sheng Min LI jiandong State Key Laboratory of Integrated Service Networks Xidian Univer sityXi’an 710071China

This paper presents a novel distributed media access control(MAC)address assignment algorithm,namely virtual grid spatial reusing(VGSR),for wireless sensor networks,which reduces the size of the MAC address efficiently on the basis of both the spatial reuse of MAC address and the mapping of geographical *** adjusting the communication range of sensor nodes,VGSR algorithm can minimize the size of MAC address and meanwhile guarantee the connectivity of the sensor *** analysis and experimental results show that VGSR algorithm is not only of low energy cost,but also scales well with the network size,with its performance superior to that of other existing algorithms.

关键词： wireless sensor networks media access control(MAC)address distributed geographical position

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典型草地地上生物量遥感反演模型的建立

农业网络信息 2013年第4期 12-15,24页

作者：张小琪盛建东武红旗谷海斌龚双凤新疆农业大学草业与环境科学学院新疆乌鲁木齐830052

利用新疆阿勒泰地区富蕴县2011年9月野外典型草地地上生物量采样数据和同期接收的环境减灾卫星(HJ1A-CCD1)的遥感图像数据,分析了归一化植被指数(NDV)I、比值植被指数(RV)I与实测草地地上生物量的一元线性和非线性回归模型,并对不同回... 详细信息

利用新疆阿勒泰地区富蕴县2011年9月野外典型草地地上生物量采样数据和同期接收的环境减灾卫星(HJ1A-CCD1)的遥感图像数据,分析了归一化植被指数(NDV)I、比值植被指数(RV)I与实测草地地上生物量的一元线性和非线性回归模型,并对不同回归模型进行分析比较。研究表明:植被指数NDVI与实测草地地上生物量之间存在较好的相关性;所建遥感植被指数与草地地上生物量的回归模型中,指数回归模型(y=3.716e26.758x,R2=0.815)最适合于监测草地地上生物量的遥感反演模型,并分析了该区域地上生物量的空间差异性。

关键词：典型草地地上生物量回归模型遥感反演

新疆山地草甸土壤全氮变化特征与影响因素的关系分析

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天津农业科学 2022年第7期28卷 34-43页

作者：廖鑫宇盛建东程军回玉素甫江·玉素音刘耘华新疆农业大学资源与环境学院新疆土壤与植物生态过程重点实验室新疆乌鲁木齐830052

为探究高山草甸土壤全氮的变化特征,以新疆山地草甸为研究对象,在全疆范围内采集样点42个,分析土壤全氮含量对年均降水(MAP)、年均温度(MAT)等气候因素,根系生物量、地上净初级生产力(ANPP)等生物量,土壤容重、土石比、土壤pH等土壤理... 详细信息

为探究高山草甸土壤全氮的变化特征,以新疆山地草甸为研究对象,在全疆范围内采集样点42个,分析土壤全氮含量对年均降水(MAP)、年均温度(MAT)等气候因素,根系生物量、地上净初级生产力(ANPP)等生物量,土壤容重、土石比、土壤pH等土壤理化性质的响应。研究结果表明:在0~100 cm土层中,土壤全氮含量随着土层深度的增加而减少;在0~5 cm、5~10 cm、10~20 cm、20~30 cm和30~50 cm土层中,MAP与土壤全氮含量呈显著峰型关系;在50~70 cm和70~100 cm土层中,MAT与土壤全氮含量呈显著负相关关系;在0~5 cm和10~20 cm土层中,土壤全氮含量与根系生物量呈显著正相关关系,在5~10 cm土层中,呈显著峰型关系;在0~100 cm范围内的7个土层中,ANPP与土壤全氮含量均呈显著正相关关系;在0~5 cm、5~10 cm、10~20 cm和30~50 cm土层中,土壤容重与土壤全氮含量呈显著负相关关系;在0~100 cm范围内的7个土层中,土石比与土壤全氮含量均没有显著相关性;土壤pH与全氮含量在20~30 cm土层中呈显著正相关关系,在50~70 cm土层中呈显著峰型关系。综上,土壤中全氮含量受多种因素的影响,这对提高山地草甸植物生产和维持生态平衡具有重要意义。

关键词：山地草甸土壤全氮气候因素生物量土壤理化性质

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地方高等院校GIS专业本科教学模式探索与改革

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科教导刊 2013年第34期 138-139,173页

作者：王新军贾宏涛武红旗盛建东蒋平安新疆农业大学草业与环境科学学院新疆乌鲁木齐830052

本文由GIS本科就业率不高和我国目前GIS产业与教育事业蓬勃发展形成鲜明对比为切入点,对地方高等院校GIS本科教学存在问题进行归纳总结,针对存在问题,从GIS学科特点和本科教育的定位进行分析的基础上,从而对地方高校GIS本科教学目标、... 详细信息

本文由GIS本科就业率不高和我国目前GIS产业与教育事业蓬勃发展形成鲜明对比为切入点,对地方高等院校GIS本科教学存在问题进行归纳总结,针对存在问题,从GIS学科特点和本科教育的定位进行分析的基础上,从而对地方高校GIS本科教学目标、课程设置及教学模式提出一些措施与对策。

关键词： GIS 本科教学探索