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基于MAX+plusII 10.0 Baseline的数字电路设计
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作者 管立新 赖昭胜 《现代电子技术》 2003年第22期57-59,共3页
讨论 MAX+plus II10 .0 Baseline的功能和特点 ,提出以 VHDL 设计语言为手段、以 MAX+plus II10 .0Baseline为平台的数字电路的设计方法。
关键词 数字电路 MAX+plusⅡ10.0baseline VHDL CPLD FPGA
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Baseline——一种容忍与检测DoS/DDoS攻击的被动方法(英文)
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作者 金舒 刘凤玉 许满武 《电力自动化设备》 EI CSCD 北大核心 2005年第6期7-13,共7页
提出一种检测DoS/DDoS攻击(拒绝服务攻击/分布式拒绝服务攻击)的“Baseline”服务体系结构,并实现了其中关键的“Shepherd”检测算法。该体系结构通过把服务及其质量是否受到影响的判断指标交由具体的通信进程来定义而具有较强的适应性... 提出一种检测DoS/DDoS攻击(拒绝服务攻击/分布式拒绝服务攻击)的“Baseline”服务体系结构,并实现了其中关键的“Shepherd”检测算法。该体系结构通过把服务及其质量是否受到影响的判断指标交由具体的通信进程来定义而具有较强的适应性,可以与各种现有入侵检测系统很好地结合且不给宿主系统增加过多的开销。同时相比其他DoS/DDoS检测方式,Baseline服务无须对Internet路由基础设施作出更改来提供支持,是一种十分可行的DoS/DDoS检测方案。在理想情况下,Baseline服务可以做到对DoSDDoS入侵零误报。 展开更多
关键词 baseline服务 可用性监视 DoS/DDoS攻击检测
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基于Baseline SVD主动学习算法的推荐系统 被引量:3
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作者 季芸 胡雪蕾 《现代电子技术》 北大核心 2015年第12期8-11,共4页
推荐系统是一种解决信息过载的新型技术,为了解决推荐系统中新用户带来的冷启动问题,提出一种基于主动学习的推荐系统。主动学习方法能有效减少需要标记的样本数量,快速建立模型,在此选择将主动学习方法和Baseline SVD推荐算法结合起来... 推荐系统是一种解决信息过载的新型技术,为了解决推荐系统中新用户带来的冷启动问题,提出一种基于主动学习的推荐系统。主动学习方法能有效减少需要标记的样本数量,快速建立模型,在此选择将主动学习方法和Baseline SVD推荐算法结合起来,通过记录模型训练得到的预估评价的改变程度,认为改变最大的样例即是最具有信息量的样例,供新用户标记,并重新训练模型。通过与其他选择策略进行实验比较,证实了该方法确实有效解决了新用户带来的冷启动问题。 展开更多
关键词 推荐系统 主动学习 baseline SVD 样例选择
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Experimental investigation on failure process and spatio-temporal evolution of rockburst in granite with a prefabricated circular hole 被引量:21
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作者 LIU Chong-yan ZHAO Guang-ming +4 位作者 XU Wen-song MENG Xiang-rui HUANG Shun-jie ZHOU Jun WANG Yun-kun 《Journal of Central South University》 SCIE EI CAS CSCD 2020年第10期2930-2944,共15页
To study the mechanism of rockburst and its spatio-temporal evolution criterion,a rockburst simulation experiment was performed on granite specimens,each with a prefabricated circular hole,under different lateral load... To study the mechanism of rockburst and its spatio-temporal evolution criterion,a rockburst simulation experiment was performed on granite specimens,each with a prefabricated circular hole,under different lateral loads.Using micro camera,acoustic emission(AE)system,and infrared thermal imager,the AE characteristics and thermal radiation temperature migration were studied during the rockburst process.Then,the failure mode and damage evolution of the surrounding rock were analyzed.The results demonstrate that increasing the lateral load can first increase and then reduce the bearing capacity of the hole.In this experiment,the hole failure process could be divided into four periods:quiet,particle ejection,stability failure and collapse.Correspondingly,the AE signals evolved from a calm stage,to have intermittent appearance;then,they were continuous with a sudden increase,and finally increased dramatically.The failure of the surrounding rock was mainly tensile failure,while shear failure tended to first increase and then decrease.Meanwhile,damage to the hole increased gradually during the particle ejection period,whereas damage to the rockburst mainly occurred in the stability failure period.The thermal radiation temperature migration exhibited warming in shallow parts,inward expansion,cooling in the shallow parts with free surface heating,inward expansion,a sudden rise in temperature of the rockburst pits,and finally specimen failure.The initial reinforcement support should fully contribute to surface support.Furthermore,an appropriate tensile capacity and good energy absorption capacity should be established in support systems for high-stress roadways. 展开更多
关键词 ROCKBURST acoustic emission spatio-temporal evolution thermal imaging
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GPS dynamic cycle slip detection and correction with baseline constraint 被引量:3
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作者 Liu Zhenkun Huang Shunji 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2009年第1期60-64,共5页
When the cycle slips take place in the attitude determination of a moving platform, the precision of the attitude will be impaired badly. A method of cycle slip detection and correction is proposed, which is suitable ... When the cycle slips take place in the attitude determination of a moving platform, the precision of the attitude will be impaired badly. A method of cycle slip detection and correction is proposed, which is suitable to the dynamic measurement using GPS carrier phase: the cycle slips detection is first achieved by triple difference observables, then the cycle slips correction is performed with baseline length constraint. The simulation results show that the proposed method is effective to the dynamic cycle slips problem. 展开更多
关键词 dynamic cycle slip dectection triple difference observable baseline constraint attitude determination.
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Joint adaptive waveform and baseline range design for bistatic radar 被引量:2
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作者 王璐璐 王宏强 +1 位作者 程永强 秦玉亮 《Journal of Central South University》 SCIE EI CAS 2014年第6期2262-2272,共11页
The problems of joint adaptive waveform design and baseline range design for bistatic radar to maximize the practical radar resolution were considered.Distinguishing from the conventional ambiguity function(AF)-based ... The problems of joint adaptive waveform design and baseline range design for bistatic radar to maximize the practical radar resolution were considered.Distinguishing from the conventional ambiguity function(AF)-based resolution which is only related with the transmitted waveform and bistatic geometry and could be regarded as the potential resolution of a bistatic radar system,the practical resolution involves the effect of waveform,signal-to-noise ratio(SNR)as well as the measurement model.Thus,it is more practical and will have further significant application in target detection and tracking.The constraint optimization procedure of joint adaptive waveform design and baseline range design for maximizing the practical resolution of bistatic radar system under dynamic target scenario was devised.Simulation results show that the range and velocity resolution are enhanced according to the adaptive waveform and bistatic radar configuration. 展开更多
关键词 ambiguity function (AF) adaptive waveform design bistatic radar baseline range design RESOLUTION
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The IUGS/IAGC Task Group on Global Geochemical Baselines 被引量:6
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作者 David B.Smith Shaun Reeder Alecos Demetriades 《地学前缘》 EI CAS CSCD 北大核心 2012年第3期1-6,共6页
The Task Group on Global Geochemical Baselines,operating under the auspices of both the International Union of Geological Sciences(IUGS) and the International Association of Geochemistry(IAGC),has the long-term goal o... The Task Group on Global Geochemical Baselines,operating under the auspices of both the International Union of Geological Sciences(IUGS) and the International Association of Geochemistry(IAGC),has the long-term goal of establishing a global geochemical database to document the concentration and distribution of chemical elements in the Earth's surface or near-surface environment.The database and accompanying element distribution maps represent a geochemical baseline against which future human-induced or natural changes to the chemistry of the land surface may be recognized and quantified.In order to accomplish this long-term goal,the activities of the Task Group include:(1) developing partnerships with countries conducting broad-scale geochemical mapping studies;(2) providing consultation and training in the form of workshops and short courses;(3) organizing periodic international symposia to foster communication among the geochemical mapping community;(4) developing criteria for certifying those projects whose data are acceptable in a global geochemical database;(5) acting as a repository for data collected by those projects meeting the criteria for standardization;(6) preparing complete metadata for the certified projects;and(7) preparing,ultimately,a global geochemical database.This paper summarizes the history and accomplishments of the Task Group since its first predecessor project was established in 1988. 展开更多
关键词 国际地质科学联合会 伴生元素 化学元素 地表环境
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Multi-scale regionalization based mining of spatio-temporal teleconnection patterns between anomalous sea and land climate events
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作者 XU Feng SHI Yan +3 位作者 DENG Min GONG Jian-ya LIU Qi-liang JIN Rui 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第10期2438-2448,共11页
Climate sequences can be applied to defining sensitive climate zones, and then the mining of spatio-temporal teleconnection patterns is useful for learning from the past and preparing for the future. However, scale-de... Climate sequences can be applied to defining sensitive climate zones, and then the mining of spatio-temporal teleconnection patterns is useful for learning from the past and preparing for the future. However, scale-dependency in this kind of pattern is still not well handled by existing work. Therefore, in this study, the multi-scale regionalization is embedded into the spatio-temporal teleconnection pattern mining between anomalous sea and land climatic events. A modified scale-space clustering algorithm is first developed to group climate sequences into multi-scale climate zones. Then, scale variance analysis method is employed to identify climate zones at characteristic scales, indicating the main characteristics of geographical phenomena. Finally, by using the climate zones identified at characteristic scales, a time association rule mining algorithm based on sliding time windows is employed to discover spatio-temporal teleconnection patterns. Experiments on sea surface temperature, sea level pressure, land precipitation and land temperature datasets show that many patterns obtained by the multi-scale approach are coincident with prior knowledge, indicating that this method is effective and reasonable. In addition, some unknown teleconnection patterns discovered from the multi-scale approach can be further used to guide the prediction of land climate. 展开更多
关键词 CLIMATE sequences ANOMALOUS climatic EVENTS spatio-temporal teleconnection patterns MULTI-SCALE REGIONALIZATION
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Enhanced multi-baseline unscented Kalman filtering phase unwrapping algorithm 被引量:5
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作者 Xianming Xie 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2016年第2期343-351,共9页
This paper presents an enhanced multi-baseline phase unwrapping algorithm by combining an unscented Kalman filter with an enhanced joint phase gradient estimator based on the amended matrix pencil model, and an optima... This paper presents an enhanced multi-baseline phase unwrapping algorithm by combining an unscented Kalman filter with an enhanced joint phase gradient estimator based on the amended matrix pencil model, and an optimal path-following strategy based on phase quality estimate function. The enhanced joint phase gradient estimator can accurately and effectively extract the phase gradient information of wrapped pixels from noisy interferograms, which greatly increases the performances of the proposed method. The optimal path-following strategy ensures that the proposed algorithm simultaneously performs noise suppression and phase unwrapping along the pixels with high-reliance to the pixels with low-reliance. Accordingly, the proposed algorithm can be predicted to obtain better results, with respect to some other algorithms, as will be demonstrated by the results obtained from synthetic data. 展开更多
关键词 multi-baseline phase unwrapping enhanced joint phase gradient estimator unscented Kalman filter
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Time-varying baseline error correction method for ground-based micro-deformation monitoring radar
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作者 LEI Tianjie WANG Jiabao +4 位作者 HUANG Pingping TAN Weixian QI Yaolong XU Wei ZHAO Chun 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2022年第4期938-950,共13页
In recent years, ground-based micro-deformation monitoring radar has attracted much attention due to its excellent monitoring capability. By controlling the repeated campaigns of the radar antenna on a fixed track, gr... In recent years, ground-based micro-deformation monitoring radar has attracted much attention due to its excellent monitoring capability. By controlling the repeated campaigns of the radar antenna on a fixed track, ground-based micro-deformation monitoring radar can accomplish repeat-pass interferometry without a space baseline and thus obtain highprecision deformation data of a large scene at one time. However, it is difficult to guarantee absolute stable installation position in every campaign. If the installation position is unstable, the stability of the radar track will be affected randomly, resulting in time-varying baseline error. In this study, a correction method for this error is developed by analyzing the error distribution law while the spatial baseline is unknown. In practice, the error data are first identified by frequency components, then the data of each one-dimensional array(in azimuth direction or range direction) are grouped based on numerical distribution period, and finally the error is corrected by the nonlinear model established with each group.This method is verified with measured data from a slope in southern China, and the results show that the method can effectively correct the time-varying baseline error caused by rail instability and effectively improve the monitoring data accuracy of groundbased micro-deformation radar in short term and long term. 展开更多
关键词 ground-based micro-deformation monitoring radar deformation monitoring time-varying baseline error compensation
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Improved spatio-temporal alignment measurement method for hull deformation
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作者 XU Dongsheng YU Yuanjin +1 位作者 ZHANG Xiaoli PENG Xiafu 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2024年第2期485-494,共10页
In this paper,an improved spatio-temporal alignment measurement method is presented to address the inertial matching measurement of hull deformation under the coexistence of time delay and large misalignment angle.Lar... In this paper,an improved spatio-temporal alignment measurement method is presented to address the inertial matching measurement of hull deformation under the coexistence of time delay and large misalignment angle.Large misalignment angle and time delay often occur simultaneously and bring great challenges to the accurate measurement of hull deformation in space and time.The proposed method utilizes coarse alignment with large misalignment angle and time delay estimation of inertial measurement unit modeling to establish a brand-new spatiotemporal aligned hull deformation measurement model.In addition,two-step loop control is designed to ensure the accurate description of dynamic deformation angle and static deformation angle by the time-space alignment method of hull deformation.The experiments illustrate that the proposed method can effectively measure the hull deformation angle when time delay and large misalignment angle coexist. 展开更多
关键词 inertial measurement spatio-temporal alignment hull deformation
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Warhead fragments motion trajectories tracking and spatio-temporal distribution reconstruction method based on high-speed stereo photography
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作者 Pengyu Hu Jiangpeng Wu +3 位作者 Zhengang Yan Meng He Chao Liang Hao Bai 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第7期162-172,共11页
High speed photography technique is potentially the most effective way to measure the motion parameter of warhead fragment benefiting from its advantages of high accuracy,high resolution and high efficiency.However,it... High speed photography technique is potentially the most effective way to measure the motion parameter of warhead fragment benefiting from its advantages of high accuracy,high resolution and high efficiency.However,it faces challenge in dense objects tracking and 3D trajectories reconstruction due to the characteristics of small size and dense distribution of fragment swarm.To address these challenges,this work presents a warhead fragments motion trajectories tracking and spatio-temporal distribution reconstruction method based on high-speed stereo photography.Firstly,background difference algorithm is utilized to extract the center and area of each fragment in the image sequence.Subsequently,a multi-object tracking(MOT)algorithm using Kalman filtering and Hungarian optimal assignment is developed to realize real-time and robust trajectories tracking of fragment swarm.To reconstruct 3D motion trajectories,a global stereo trajectories matching strategy is presented,which takes advantages of epipolar constraint and continuity constraint to correctly retrieve stereo correspondence followed by 3D trajectories refinement using polynomial fitting.Finally,the simulation and experimental results demonstrate that the proposed method can accurately track the motion trajectories and reconstruct the spatio-temporal distribution of 1.0×10^(3)fragments in a field of view(FOV)of 3.2 m×2.5 m,and the accuracy of the velocity estimation can achieve 98.6%. 展开更多
关键词 Warhead fragment measurement High speed photography Stereo vision Multi-object tracking spatio-temporal reconstruction
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A cloud model target damage effectiveness assessment algorithm based on spatio-temporal sequence finite multilayer fragments dispersion
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作者 Hanshan Li Xiaoqian Zhang Junchai Gao 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第10期48-64,共17页
To solve the problem of target damage assessment when fragments attack target under uncertain projectile and target intersection in an air defense intercept,this paper proposes a method for calculating target damage p... To solve the problem of target damage assessment when fragments attack target under uncertain projectile and target intersection in an air defense intercept,this paper proposes a method for calculating target damage probability leveraging spatio-temporal finite multilayer fragments distribution and the target damage assessment algorithm based on cloud model theory.Drawing on the spatial dispersion characteristics of fragments of projectile proximity explosion,we divide into a finite number of fragments distribution planes based on the time series in space,set up a fragment layer dispersion model grounded in the time series and intersection criterion for determining the effective penetration of each layer of fragments into the target.Building on the precondition that the multilayer fragments of the time series effectively assail the target,we also establish the damage criterion of the perforation and penetration damage and deduce the damage probability calculation model.Taking the damage probability of the fragment layer in the spatio-temporal sequence to the target as the input state variable,we introduce cloud model theory to research the target damage assessment method.Combining the equivalent simulation experiment,the scientific and rational nature of the proposed method were validated through quantitative calculations and comparative analysis. 展开更多
关键词 Target damage Cloud model Fragments dispersion Effectiveness assessment spatio-temporal sequence
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Distributed spatio-temporal generative adversarial networks
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作者 QIN Chao GAO Xiaoguang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2020年第3期578-592,共15页
Owing to the wide range of applications in various fields,generative models have become increasingly popular.However,they do not handle spatio-temporal features well.Inspired by the recent advances in these models,thi... Owing to the wide range of applications in various fields,generative models have become increasingly popular.However,they do not handle spatio-temporal features well.Inspired by the recent advances in these models,this paper designs a distributed spatio-temporal generative adversarial network(STGAN-D)that,given some initial data and random noise,generates a consecutive sequence of spatio-temporal samples which have a logical relationship.This paper builds a spatio-temporal discriminator to distinguish whether the samples generated by the generator meet the requirements for time and space coherence,and builds a controller for distributed training of the network gradient updated to separate the model training and parameter updating,to improve the network training rate.The model is trained on the skeletal dataset and the traffic dataset.In contrast to traditional generative adversarial networks(GANs),the proposed STGAN-D can generate logically coherent samples with the corresponding spatial and temporal features while avoiding mode collapse.In addition,this paper shows that the proposed model can generate different styles of spatio-temporal samples given different random noise inputs,and the controller can improve the network training rate.This model will extend the potential range of applications of GANs to areas such as traffic information simulation and multiagent adversarial simulation. 展开更多
关键词 distributed spatio-temporal generative adversarial network(STGAN-D) spatial discriminator temporal discriminator speed controller
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Multi-baseline extended particle filtering phase unwrapping algorithm based on amended matrix pencil model and quantized path-following strategy
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作者 XIE Xianming ZENG Qingning 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2019年第1期78-84,共7页
This paper proposes a new multi-baseline extended particle filtering phase unwrapping algorithm which combines an extended particle filter with an amended matrix pencil model and a quantized path-following strategy. T... This paper proposes a new multi-baseline extended particle filtering phase unwrapping algorithm which combines an extended particle filter with an amended matrix pencil model and a quantized path-following strategy. The contributions to multibaseline synthetic aperture radar(SAR) interferometry are as follows: a new recursive multi-baseline phase unwrapping model based on an extended particle filter is built, and the amended matrix pencil model is used to acquire phase gradient information with a higher precision and lower computational cost, and the quantized path-following strategy is introduced to guide the proposed phase unwrapping procedure to efficiently unwrap wrapped phase image along the paths routed by a phase derivative variance map. 展开更多
关键词 multi-baseline phase unwrapping INTERFEROMETRIC synthetic APERTURE radar (InSAR) EXTENDED particle filter.
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福建省草地贪夜蛾对5种常用杀虫剂的抗药性 被引量:1
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作者 邱良妙 陈秀琴 +2 位作者 卢学松 刘必炮 刘其全 《生物安全学报(中英文)》 北大核心 2025年第2期155-161,179,共8页
【目的】明确草地贪夜蛾对5种常用杀虫剂的相对敏感基线及其在福建省的抗药性水平,并评价其低龄幼虫对这些药剂的敏感性。【方法】以浸叶法测定5种杀虫剂对草地贪夜蛾相对敏感种群1、2龄幼虫的毒力,监测福建省3个不同地区草地贪夜蛾田... 【目的】明确草地贪夜蛾对5种常用杀虫剂的相对敏感基线及其在福建省的抗药性水平,并评价其低龄幼虫对这些药剂的敏感性。【方法】以浸叶法测定5种杀虫剂对草地贪夜蛾相对敏感种群1、2龄幼虫的毒力,监测福建省3个不同地区草地贪夜蛾田间种群的抗药性水平;以LC _(50)的95%置信限不重叠作为标准,判断不同种群的同一龄期幼虫或同一种群的1、2龄幼虫对同一种药剂敏感性差异显著性。【结果】5种杀虫剂对草地贪夜蛾相对敏感种群幼虫的毒力大小顺序依次为甲维盐>乙基多杀菌素>氯虫苯甲酰胺>虱螨脲>茚虫威,同一药剂对1龄幼虫的毒力大于2龄,其中,甲维盐、乙基多杀菌素和虱螨脲对1龄幼虫毒力测试的χ^(2)值小于2龄,P值更大,虽然氯虫苯甲酰胺和茚虫威对1龄幼虫毒力测试的χ^(2)值略大于2龄,但P值均大于0.9190;福建3个地区的草地贪夜蛾种群对甲维盐和茚虫威的抗性水平处于敏感性下降至低水平抗性之间,对氯虫苯甲酰胺已产生低水平抗性,对乙基多杀菌素属于敏感性水平下降阶段,而对虱螨脲仍属于敏感水平。【结论】福建省草地贪夜蛾种群对虱螨脲保持敏感水平,对其他4种常用药剂总体上处于敏感性下降至低水平抗性阶段;1、2龄幼虫均适合作为草地贪夜蛾毒力测定的靶标试虫,但相较于2龄幼虫,12 h内孵化且未喂食物的1龄幼虫适合性更好。 展开更多
关键词 草地贪夜蛾 杀虫剂 浸叶法 敏感基线 毒力 抗药性
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基于SBAS InSAR技术的叙古高速沿线滑坡识别与监测 被引量:1
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作者 杨辰 金源 +1 位作者 邓飞 史绪国 《自然资源遥感》 北大核心 2025年第1期161-168,共8页
叙永—古蔺高速公路(叙古高速)位于四川盆地南缘,线路周边地质条件复杂,其安全运营受到地质灾害威胁,因此,叙古高速沿线地质灾害的识别分析具有十分重要的意义。合成孔径雷达干涉测量(interferometric synthe-tic aperture Radar,InSAR... 叙永—古蔺高速公路(叙古高速)位于四川盆地南缘,线路周边地质条件复杂,其安全运营受到地质灾害威胁,因此,叙古高速沿线地质灾害的识别分析具有十分重要的意义。合成孔径雷达干涉测量(interferometric synthe-tic aperture Radar,InSAR)技术具有全天时全天候、覆盖范围大和毫米级地表形变监测的优势,在广域滑坡识别监测中发挥了重要作用。基于此,采用小基线集(small baseline subset,SBAS)InSAR技术对2017年2月—2020年9月Sentinel-1升降轨数据集进行处理分析,获取叙古高速沿线地表形变速率,共探测到包括集美滑坡等在内的18处滑坡体,分析发现滑坡形变主要与人为活动相关。结果同时表明,升降轨数据结合有助于更准确地识别灾害点分布。随着数据的积累与技术的不断发展,InSAR技术可以在地质灾害防治中发挥越来越重要的作用。 展开更多
关键词 滑坡探测 合成孔径雷达干涉测量 叙古高速 小基线数据集
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瓦里关30年大气本底观测研究回顾和展望
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作者 车慧正 张晓春 +5 位作者 王剑琼 沈小静 张根 徐婉筠 郑宇 张小曳 《气候变化研究进展》 北大核心 2025年第2期186-197,共12页
为了应对气候变化并对大气成分及其相关物理、化学特性等进行系统的全球化观测,在青海省瓦里关山建成了欧亚大陆腹地第一个全球大气本底基准观象台(以下简称瓦里关本底站),开展了包括温室气体、气溶胶、臭氧、辐射、酸雨等关键成分的长... 为了应对气候变化并对大气成分及其相关物理、化学特性等进行系统的全球化观测,在青海省瓦里关山建成了欧亚大陆腹地第一个全球大气本底基准观象台(以下简称瓦里关本底站),开展了包括温室气体、气溶胶、臭氧、辐射、酸雨等关键成分的长期观测,并开展了其与天气、气候、环境和人体健康效应相互作用的研究。文中系统回顾瓦里关本底站过去30年的发展历程、主要观测项目及其研究成果并展望未来的发展方向和研究重点,并指出了观测技术的提升、创新和新观测项目的引入是进一步精准描述本底大气特征对全球气候与环境变化多尺度响应的重要发展方向。 展开更多
关键词 瓦里关本底站 大气成分 观测 气候变化
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炮身晃动量对轴系平行度影响研究
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作者 陈永刚 刘杰 +1 位作者 黄诚 余继良 《火炮发射与控制学报》 北大核心 2025年第4期1-6,共6页
现代火炮包含多种火力组件和火控组件,各组件采用统一的轴系基准,通过校靶使轴系的平行度达到要求,以保证火炮在雷达跟踪、光电跟踪、车长镜瞄准、火控解算等情况下,武器综合控制系统控制火力组件向准确的目标未来点发射炮弹、主防弹药... 现代火炮包含多种火力组件和火控组件,各组件采用统一的轴系基准,通过校靶使轴系的平行度达到要求,以保证火炮在雷达跟踪、光电跟踪、车长镜瞄准、火控解算等情况下,武器综合控制系统控制火力组件向准确的目标未来点发射炮弹、主防弹药、导弹等,完成打击任务。火炮轴系基准是现代火炮主要组件安装与轴系平行度调校的基础,直接影响瞄准误差。以某双管火炮为例,针对其射击后平行度超差问题,通过研究其轴系基准、平行度要求及调试过程,估算炮身晃动量,揭示了炮身晃动量对火炮轴系基准及轴系平行度影响显著,给出了避免平行度超差的措施。研究结果对火炮轴系基准设计、轴系平行度误差分配及检验验收具有一定参考作用。 展开更多
关键词 火炮 轴系基准 晃动量 平行度
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中国土壤硼地球化学异常特征与找矿远景区预测
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作者 柳青青 王学求 +6 位作者 张必敏 周建 王玮 刘汉粮 刘东盛 周怡宁 常婵 《地学前缘》 北大核心 2025年第1期50-60,共11页
硼是一种新兴战略矿产,在现代高新技术产业中应用广泛。近年来,硼的需求持续上升,硼矿资源勘查也日益受到重视。本文依托中国地球化学基准值计划所采集的3380件汇水域深层土壤数据,提供了全国B元素地球化学分布和异常特征。全国汇水域... 硼是一种新兴战略矿产,在现代高新技术产业中应用广泛。近年来,硼的需求持续上升,硼矿资源勘查也日益受到重视。本文依托中国地球化学基准值计划所采集的3380件汇水域深层土壤数据,提供了全国B元素地球化学分布和异常特征。全国汇水域土壤深层样品B平均含量为46.4μg/g,B整体上具有南高北低、连片分布的特点,可划分为5个地球化学分区,分别为东北与内蒙古东部地区(Ⅰ)、西北部地区(Ⅱ)、华北地区(Ⅲ)、青藏地区(Ⅳ)和南方地区(Ⅴ)。以B含量70.9和52.4μg/g(累频85%)分别作为南北方异常下限,共圈定出37个B地球化学异常,在全国圈定10个地球化学省和9个小规模异常。根据B异常空间分布,结合地质背景和硼矿床分布,进一步划分出9个成矿远景区,建议加大盐湖型硼矿的找矿勘查力度,并将硬岩(海相沉积)型硼矿作为下一步勘查目标。 展开更多
关键词 中国地球化学基准 找矿远景区 深层土壤 地球化学异常
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