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A novel detection method for warhead fragment targets in optical images under dynamic strong interference environments
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作者 Guoyi Zhang Hongxiang Zhang +4 位作者 Zhihua Shen Deren Kong Chenhao Ning Fei Shang Xiaohu Zhang 《Defence Technology(防务技术)》 2025年第1期252-270,共19页
A measurement system for the scattering characteristics of warhead fragments based on high-speed imaging systems offers advantages such as simple deployment,flexible maneuverability,and high spatiotemporal resolution,... A measurement system for the scattering characteristics of warhead fragments based on high-speed imaging systems offers advantages such as simple deployment,flexible maneuverability,and high spatiotemporal resolution,enabling the acquisition of full-process data of the fragment scattering process.However,mismatches between camera frame rates and target velocities can lead to long motion blur tails of high-speed fragment targets,resulting in low signal-to-noise ratios and rendering conventional detection algorithms ineffective in dynamic strong interference testing environments.In this study,we propose a detection framework centered on dynamic strong interference disturbance signal separation and suppression.We introduce a mixture Gaussian model constrained under a joint spatialtemporal-transform domain Dirichlet process,combined with total variation regularization to achieve disturbance signal suppression.Experimental results demonstrate that the proposed disturbance suppression method can be integrated with certain conventional motion target detection tasks,enabling adaptation to real-world data to a certain extent.Moreover,we provide a specific implementation of this process,which achieves a detection rate close to 100%with an approximate 0%false alarm rate in multiple sets of real target field test data.This research effectively advances the development of the field of damage parameter testing. 展开更多
关键词 Damage parameter testing Warhead fragment target detection High-speed imaging systems Dynamic strong interference disturbance suppression Variational bayesian inference Motion target detection Faint streak-like target detection
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磁性阿克拉霉素纳米粒的研制和理化性质
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作者 张伟 沈锡中 +1 位作者 邓勇辉 王吉耀 《复旦学报(医学版)》 CAS CSCD 北大核心 2005年第2期155-159,共5页
目的 制备纳米级磁性阿克拉霉素微粒 ,考察其理化性质和磁场响应性。方法 运用化学沉淀法制备Fe3 O4纳米颗粒 ,并与阿克拉霉素水溶液分散在正己烷油相体系。采用反相微乳液界面聚合的方法生成聚合物将水液滴包埋 ,由此制备内含磁性颗... 目的 制备纳米级磁性阿克拉霉素微粒 ,考察其理化性质和磁场响应性。方法 运用化学沉淀法制备Fe3 O4纳米颗粒 ,并与阿克拉霉素水溶液分散在正己烷油相体系。采用反相微乳液界面聚合的方法生成聚合物将水液滴包埋 ,由此制备内含磁性颗粒和阿克拉霉素的磁性纳米载药系统 ,并通过扫描电镜、透射电镜、动态光散射磁强计等考察磁性阿克拉霉素纳米粒的理化性质及体内外磁场响应性。结果 磁性阿克拉霉素纳米粒平均粒径2 1 0nm ,阿克拉霉素载药率 1 0 .0 %,包封率 36 .2 %。制备过程中的各参数包括单体用量、体系油水相体积比例、有机溶剂的种类和乳化剂的用量等都会影响磁性阿克拉霉素纳米粒粒径和阿克拉霉素包封率。制备后 4℃保存 ,3个月稳定性好。结论 磁性阿克拉霉素纳米粒粒径小 ,载药率和包封率高 ,体外具有良好的磁场响应性。 展开更多
关键词 Fe3O4 4
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Pol-ISARSpaceTarget-1.0:极化ISAR空间目标精细识别电磁仿真数据集
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作者 陈思伟 李铭典 崔兴超 《信号处理》 北大核心 2025年第8期1443-1454,共12页
以卫星为代表的空间目标在遥感测绘、气象监测、无线通信、侦察监视等领域发挥着重要作用,同时也是空间态势感知的重要对象。极化逆合成孔径雷达(Inverse Synthetic Aperture Radar,ISAR)能够获取目标的高分辨率图像信息和敏感于目标结... 以卫星为代表的空间目标在遥感测绘、气象监测、无线通信、侦察监视等领域发挥着重要作用,同时也是空间态势感知的重要对象。极化逆合成孔径雷达(Inverse Synthetic Aperture Radar,ISAR)能够获取目标的高分辨率图像信息和敏感于目标结构的极化散射信息,在空间态势感知中具有独特优势。然而,极化ISAR空间目标实测数据难以公开。同时,部件级精细标注难度大且研究少。因此,当前缺少公开的极化ISAR空间目标数据集。针对上述挑战,为促进该领域研究发展,本文构建并公开了首个极化ISAR空间目标精细识别电磁仿真数据集(Pol-ISARSpaceTarget-1.0),包括抛物面天线雷达卫星、平板天线雷达卫星、通信卫星和光学卫星等6型空间目标极化ISAR图像数据和9类关键部件语义标注数据。本文介绍了该数据集构成、电磁仿真成像及部件标注流程。在此基础上,以空间目标部件识别为例,选取典型深度学习目标识别方法验证了数据集的有效性,并形成基准结果,供相关学者参考。该数据集空间目标类型多样、极化信息完备、部件标注种类丰富,可为空间目标精细分类识别等提供基础数据支撑。 展开更多
关键词
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河套盆地生物气成藏条件及勘探前景 被引量:18
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作者 杨华 李民才 崔永平 《中国石油勘探》 CAS 2005年第3期16-21,共6页
河套盆地呼和坳陷第四系、上新统气源岩厚1200m以上,有机碳平均含量0.59%,有机质类型为混合型及腐殖型,未成熟,处于生物化学生气阶段,具有大规模生气能力。大量水文浅井冒气泡,证实了生物气的存在。储层为浅湖、半深湖相粉细砂岩、泥质... 河套盆地呼和坳陷第四系、上新统气源岩厚1200m以上,有机碳平均含量0.59%,有机质类型为混合型及腐殖型,未成熟,处于生物化学生气阶段,具有大规模生气能力。大量水文浅井冒气泡,证实了生物气的存在。储层为浅湖、半深湖相粉细砂岩、泥质粉砂岩,成岩程度低,岩性疏松,孔隙度大于20%,储气能力强。第四系150~300m段发育泥岩及芒硝、腐殖土,具有较强的封盖能力,是比较理想的盖层段。生物气富集的主要控制因素为圈闭。通过类比,河套盆地成藏条件与柴达木盆地相似,资源潜力大,勘探前景好。 展开更多
关键词 300m
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含靶向和造影双功能基的PEO的合成
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作者 翟慕衡 商永嘉 +3 位作者 杜宝辉 胡继萍 张德兴 沈良骏 《应用化学》 CAS CSCD 北大核心 2005年第5期517-520,共4页
用-4胺基-N-2(-嘧啶)苯磺酰胺钠(磺胺嘧啶钠)作引发剂,引发环氧乙烷(EO)开环聚合,反应在非均相中进行,用自制的3,5-二-(N乙酰氨基)-2,4,6-三碘苯甲酰氯(泛影酰氯)作封端剂封端该反应,合成了含有靶向和造影双功能基团的聚环氧乙烷(PEO)... 用-4胺基-N-2(-嘧啶)苯磺酰胺钠(磺胺嘧啶钠)作引发剂,引发环氧乙烷(EO)开环聚合,反应在非均相中进行,用自制的3,5-二-(N乙酰氨基)-2,4,6-三碘苯甲酰氯(泛影酰氯)作封端剂封端该反应,合成了含有靶向和造影双功能基团的聚环氧乙烷(PEO)大分子,反应在80℃下约需96h完成,产率为87%~90%。用IR、1HNMR、UV测试技术对聚合产物进行了表征,用VPO和GPC测定了聚合物的分子量及分子量分布。通过改变引发剂的用量可调节PEO的聚合度,得到不同分子量的PEO产物,引发剂用量较少时,产物的均匀性变好。所得产物的分子量范围为2692~11040,分子量分布的范围为1.195~1.704。不同分子量的PEO分子中靶向功能基含量的范围为2.13%~8.98%,造影功能基含量的范围为5.25%~21.72%。室温下的溶解度测试表明,产物易溶于水和DMSO、DMF、THF、氯仿、乙醇、吡啶、苯、甲苯、丙酮等溶剂。 展开更多
关键词 PEO ^1HNMR DMSO GPC VPO
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Joint resource allocation scheme for target tracking in distributed MIMO radar systems 被引量:2
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作者 ZHENG Na’e SUN Yang +1 位作者 SONG Xiyu CHEN Song 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2019年第4期709-719,共11页
A joint resource allocation scheme concerned with the sensor subset,power and bandwidth for range-only target tracking in multiple-input multiple-output(MIMO)radar systems is proposed.By selecting an optimal subset of... A joint resource allocation scheme concerned with the sensor subset,power and bandwidth for range-only target tracking in multiple-input multiple-output(MIMO)radar systems is proposed.By selecting an optimal subset of sensors with the predetermined size and implementing the power allocation and bandwidth strategies among them,this algorithm can help achieving a better performance within the same resource constraints.Firstly,the Bayesian Cramer-Rao bound(BCRB)is derived from it.Secondly,a criterion for minimizing the BCRB at the target location among all targets tracking in a certain range is derived.Thirdly,the optimization problem involved with three variable vectors is formulated,which can be simplified by deriving the relationship between the optimal power allocation vector and the bandwidth allocation vector.Then,the simplified optimization problem is solved by the cyclic minimization algorithm incorporated with the sequential parametric convex approximation(SPCA)algorithm.Finally,the validity of the proposed method is demonstrated with simulation results. 展开更多
关键词 distributed MULTIPLE-INPUT multiple-output(MIMO)radar target tracking JOINT RESOURCE alloction sensor SUBSET selection(SSS) optimal power and bandwidth allocation(OPBA)
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国内矿物治理重金属废水研究进展与展望 被引量:17
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作者 王吉中 李胜荣 +1 位作者 刘宝林 佟景贵 《矿物岩石地球化学通报》 CAS CSCD 2005年第2期159-164,共6页
综述了我国利用天然矿物治理重金属废水方面的研究新成果。天然铁的硫化物、天然铁锰的氧化物、方解石与磷灰石等具有良好的表面吸附与氧化还原化学活性;不同介质中它们能不同程度地表现出对Cr6+、Pb2+、Hg2+、Cd2+等重金属离子的吸附作... 综述了我国利用天然矿物治理重金属废水方面的研究新成果。天然铁的硫化物、天然铁锰的氧化物、方解石与磷灰石等具有良好的表面吸附与氧化还原化学活性;不同介质中它们能不同程度地表现出对Cr6+、Pb2+、Hg2+、Cd2+等重金属离子的吸附作用,可广泛用于重金属废水处理。矿物吸附重金属离子机理的研究表明,矿物对重金属的吸附是矿物表面与无机重金属离子之间的表面作用过程,包括矿物表面功能基与重金属离子的配位反应、矿物表面氧化还原反应和沉淀转化作用,以及矿物表面离子交换吸附作用等。 展开更多
关键词 CR^6%PLUS% PB^2%PLUS% HG^2%PLUS% CD^2%PLUS%
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重力、地震联合反演方法确定深层油气藏的分布——以锡林凹陷石炭系分布为例 被引量:10
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作者 刘天佑 杨宇山 +2 位作者 李媛媛 邓荣来 宋桂桥 《天然气工业》 EI CAS CSCD 北大核心 2005年第5期34-36,共3页
文章以内蒙巴彦浩特盆地锡林凹陷为例,说明重力、地震联合反演方法在确定深部生油目的层石炭纪地层的应用效果。巴彦浩特盆地多期构造影响,造成逆冲、剥蚀及断块作用十分显著;在地震资料解释中,同相轴难以追踪或会误追踪。采用2 D重力... 文章以内蒙巴彦浩特盆地锡林凹陷为例,说明重力、地震联合反演方法在确定深部生油目的层石炭纪地层的应用效果。巴彦浩特盆地多期构造影响,造成逆冲、剥蚀及断块作用十分显著;在地震资料解释中,同相轴难以追踪或会误追踪。采用2 D重力模型反演与地震走时反演的联合反演对x5,x6线高精度重力与地震资料进行处理,指出了原根据地震资料确定的局部高隆起不是目的层石炭系而是剥蚀殆尽的寒武系;同时还给出了锡林凹陷石炭系的分布范围,避免了勘探风险。 展开更多
关键词
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Fusion of Dual-targeting Peptides with MAP30 Promotes the Apoptosis of MDA-MB-231 Breast Cancer Cells
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作者 YANG Yi-Xuan WANG Xin-Yi +5 位作者 CHEN Wei-Wei GAN Li SUN Yu LIN Tong ZHAO Wei-Chun ZHU Zhen-Hong 《中国生物化学与分子生物学报》 北大核心 2025年第2期260-272,共13页
Momordica antiviral protein 30 kD(MAP30)is a type I ribosome-inactivating protein(RIP)with antibacterial,anti-HIV and antitumor activities but lacks the ability to target tumor cells.To increase its tumor-targeting ab... Momordica antiviral protein 30 kD(MAP30)is a type I ribosome-inactivating protein(RIP)with antibacterial,anti-HIV and antitumor activities but lacks the ability to target tumor cells.To increase its tumor-targeting ability,the arginine-glycine-aspartic(RGD)peptide and the epidermal growth factor receptor interference(EGFRi)peptide were fused with MAP30,which was named ELRL-MAP30.The efficiency of targeted therapy for triple-negative breast cancer(TNBC)MDA-MB-231 cells,which lack the expression of estrogen receptor(ER),Progesterone receptor(PgR)and human epidermal growth factor receptor-2(HER2),is limited.In this study,we focus on exploring the effect and mechanism of ELRL-MAP30 on TNBC MDA-MB-231 cells.First,we discovered that ELRL-MAP30 significantly inhibited the migration and invasion of MDA-MB-231 cells and induced MDA-MB-231 cell apoptosis.Moreover,ELRL-MAP30 treatment resulted in a significant increase in Bax expression and a decrease in Bcl-2 expression.Furthermore,ELRL-MAP30 triggered apoptosis via the Fak/EGFR/Erk and Ilk/Akt signaling pathways.In addition,recombinant ELRL-MAP30 can inhibit chicken embryonic angiogenesis,and also inhibit the tube formation ability of human umbilical vein endothelial cells(HUVECs),indicating its potential therapeutic effects on tumor angiogenesis.Collectively,these results indicate that ELRL-MAP30 has significant tumor-targeting properties in MDA-MB-231 cancer cells and reveals potential therapeutic effects on angiogenesis.These findings indicate the potential role of ELRL-MAP30 in the targeted treatment of the TNBC cell line MDA-MB-231. 展开更多
关键词 arginine-glycine-aspartic peptide(RGD) epidermal growth factor receptor interference peptide(EGFRi) momordica antiviral protein(MAP30) MDA-MB-231 cell tumor targeting APOPTOSIS
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Distributed event-triggered control for UAV swarm target fencing with network connectivity preservation and collision avoidance
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作者 Xiuxia Yang Hao Yu +1 位作者 Yi Zhang Wenqiang Yao 《Defence Technology(防务技术)》 2025年第8期412-427,共16页
This paper proposes a distributed event-triggered control(ETC)framework to address cooperative target fencing challenges in UAV swarm.The proposed architecture eliminates the reliance on preset formation parameters wh... This paper proposes a distributed event-triggered control(ETC)framework to address cooperative target fencing challenges in UAV swarm.The proposed architecture eliminates the reliance on preset formation parameters while achieving multi-objective cooperative control for target fencing,network connectivity preservation,collision avoidance,and communication efficiency optimization.Firstly,a differential state observer is constructed to obtain the target's unmeasurable states.Secondly,leveraging swarm selforganization principles,a geometric-constraint-free distributed fencing controller is designed by integrating potential field methods with consensus theory.The controller dynamically adjusts inter-UAV distances via single potential function,enabling coordinated optimization of persistent network connectivity and collision-free motion during target fencing.Thirdly,a dual-threshold ETC mechanism based on velocity consensus deviation and fencing error is proposed,which can be triggered based on task features to dynamically adjust the communication frequency,significantly reduce the communication burden and exclude Zeno behavior.Theoretical analysis demonstrates the stability of closed-loop systems.Multi-scenario simulations show that the proposed method can achieve robust fencing under target maneuverability,partial UAV failures,and communication disturbances. 展开更多
关键词 Dual-threshold ETC mechanism UAV swarm Cooperative control Distributed control target fencing Differential state observer
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Joint planning method for cross-domain unmanned swarm target assignment and mission trajectory
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作者 WANG Ning LIANG Xiaolong +2 位作者 LI Zhe HOU Yueqi YANG Aiwu 《Journal of Systems Engineering and Electronics》 2025年第3期736-753,共18页
Compared with single-domain unmanned swarms,cross-domain unmanned swarms continue to face new challenges in terms of platform performance and constraints.In this paper,a joint unmanned swarm target assignment and miss... Compared with single-domain unmanned swarms,cross-domain unmanned swarms continue to face new challenges in terms of platform performance and constraints.In this paper,a joint unmanned swarm target assignment and mission trajectory planning method is proposed to meet the requirements of cross-domain unmanned swarm mission planning.Firstly,the different performances of cross-domain heterogeneous platforms and mission requirements of targets are characterised by using a collection of operational resources.Secondly,an algorithmic framework for joint target assignment and mission trajectory planning is proposed,in which the initial planning of the trajectory is performed in the target assignment phase,while the trajectory is further optimised afterwards.Next,the estimation of the distribution algorithms is combined with the genetic algorithm to solve the objective function.Finally,the algorithm is numerically simulated by specific cases.Simulation results indicate that the proposed algorithm can perform effective task assignment and trajectory planning for cross-domain unmanned swarms.Furthermore,the solution performance of the hybrid estimation of distribution algorithm(EDA)-genetic algorithm(GA)algorithm is better than that of GA and EDA. 展开更多
关键词 cross-domain swarm unmanned system target assignment trajectory planning joint planning hybrid estimation of distribution algorithm(EDA)-genetic algorithm(GA)
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Fast density peak-based clustering algorithm for multiple extended target tracking 被引量:4
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作者 SHEN Xinglin SONG Zhiyong +1 位作者 FAN Hongqi FU Qiang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2019年第3期435-447,共13页
The key challenge of the extended target probability hypothesis density (ET-PHD) filter is to reduce the computational complexity by using a subset to approximate the full set of partitions. In this paper, the influen... The key challenge of the extended target probability hypothesis density (ET-PHD) filter is to reduce the computational complexity by using a subset to approximate the full set of partitions. In this paper, the influence for the tracking results of different partitions is analyzed, and the form of the most informative partition is obtained. Then, a fast density peak-based clustering (FDPC) partitioning algorithm is applied to the measurement set partitioning. Since only one partition of the measurement set is used, the ET-PHD filter based on FDPC partitioning has lower computational complexity than the other ET-PHD filters. As FDPC partitioning is able to remove the spatially close clutter-generated measurements, the ET-PHD filter based on FDPC partitioning has good tracking performance in the scenario with more clutter-generated measurements. The simulation results show that the proposed algorithm can get the most informative partition and obviously reduce computational burden without losing tracking performance. As the number of clutter-generated measurements increased, the ET-PHD filter based on FDPC partitioning has better tracking performance than other ET-PHD filters. The FDPC algorithm will play an important role in the engineering realization of the multiple extended target tracking filter. 展开更多
关键词 FAST DENSITY peak-based clustering (FDPC) MULTIPLE extended target partition probability hypothesis DENSITY (PHD) filter track.
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用LAHET和MCNP程序研究散裂中子靶的中子学性能 被引量:1
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作者 杨永伟 李浩泉 经荥清 《原子能科学技术》 EI CAS CSCD 北大核心 2005年第3期205-208,共4页
利用LAHET和MCNP程序对ADS散裂中子靶进行模拟计算。因靶的基本物理性质随束流和靶形状的变化而改变,所以首先评估了源强和靶的几何形状对靶性质的可能影响,然后计算长1.2m、直径为0.6m的圆柱形液态铅靶在1GeV质子轰击下,靶内中子的产... 利用LAHET和MCNP程序对ADS散裂中子靶进行模拟计算。因靶的基本物理性质随束流和靶形状的变化而改变,所以首先评估了源强和靶的几何形状对靶性质的可能影响,然后计算长1.2m、直径为0.6m的圆柱形液态铅靶在1GeV质子轰击下,靶内中子的产生和泄漏及能量的沉积等。与文献数据、实验数据进行了比较,符合良好。计算结果还表明:源强和几何的选择对中子产生和泄漏可产生较大影响;用液态铅作散裂靶时,中子产额和泄漏额较高,且泄漏能谱在可利用范围内,但能量沉积在靶中的分布极不均匀,这可能给传热带来问题。 展开更多
关键词 MCNP ADS
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西部复杂山地勘探走势分析 被引量:21
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作者 苟量 贺振华 《石油地球物理勘探》 EI CSCD 北大核心 2005年第2期248-251,125-252,共4页
复杂山地山前带油气资源丰富,是中国西部地区的主要勘探领域之一。西部山地山前带具有地表类型复杂多变、地下逆掩推覆构造特征强烈的双重复杂性,给勘探资料的采集、处理和解释增加了难度。集中表现为地震资料信噪比低及构造精度差两个... 复杂山地山前带油气资源丰富,是中国西部地区的主要勘探领域之一。西部山地山前带具有地表类型复杂多变、地下逆掩推覆构造特征强烈的双重复杂性,给勘探资料的采集、处理和解释增加了难度。集中表现为地震资料信噪比低及构造精度差两个问题,也成为发展西部地震勘探的技术瓶颈。经过近十年的技术攻关,已形成了一套复杂山地地震勘探经验,成功攻克了一些复杂山地构造,找到了位于库车前陆盆地山前带的克拉2气田和迪拉2气田。但是,这种成功并不意味着西部其他山地勘探问题也会迎刃而解。由于我国西部复杂山地地震地质条件复杂多变,必须不断地针对具体存在的问题,研发新技术、新装备。 展开更多
关键词 西 2
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肥胖幼儿减肥运动处方的研制及效果观察 被引量:11
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作者 谭思洁 于学礼 《中国运动医学杂志》 CAS CSCD 北大核心 2005年第4期439-442,共4页
目的:探讨肥胖幼儿适宜运动心率,在此基础上研制肥胖幼儿减肥运动处方。方法:对26名4~6岁肥胖幼儿进行渐增负荷乳酸阈运动实验,采用血乳酸—心率拐点法确定运动处方强度控制的靶心率,根据靶心率设计幼儿减肥运动处方,并对受试者进行8... 目的:探讨肥胖幼儿适宜运动心率,在此基础上研制肥胖幼儿减肥运动处方。方法:对26名4~6岁肥胖幼儿进行渐增负荷乳酸阈运动实验,采用血乳酸—心率拐点法确定运动处方强度控制的靶心率,根据靶心率设计幼儿减肥运动处方,并对受试者进行8周减肥运动处方实验。结果:经过8周减肥运动处方实验,肥胖儿体重平均减轻1.31kg,皮脂厚度平均减小4.6mm,腰围平均缩小2.6cm;心功能较实验前明显增长(P<0.05),10m×2往返跑、立定跳远成绩较实验前明显提高(P<0.01)。结论:建议4~6岁肥胖幼儿运动锻炼的适宜心率为126.3次/分~165.8次/分。本研究设计的肥胖幼儿减肥运动处方合理、安全、有效,参加实验的肥胖幼儿身体素质显著提高,整个实验期未进行任何饮食控制,获得了良好的减肥效果。 展开更多
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基于传感器参数和目标轮廓中心的自动配准算法研究 被引量:16
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作者 刘松涛 王学伟 +1 位作者 周晓东 王成刚 《光学精密工程》 EI CAS CSCD 北大核心 2005年第3期354-363,共10页
通过对光电成像型反舰导弹的成像过程分析,提出了一种自动配准算法。其基本思路是将图像变换模型分解,逐步简化。可见光和红外图像配准时的变换为仿射变换。首先,利用传感器参数的调整,消除图像间的比例变化,将仿射变换简化为刚体变换;... 通过对光电成像型反舰导弹的成像过程分析,提出了一种自动配准算法。其基本思路是将图像变换模型分解,逐步简化。可见光和红外图像配准时的变换为仿射变换。首先,利用传感器参数的调整,消除图像间的比例变化,将仿射变换简化为刚体变换;然后,依赖图像信息,用形态学边缘检测的方法求取目标的轮廓中心,以此为控制点消除图像间的平移变化,实现图像的完全配准;最后,通过观察海天线是否重合以及利用均方根误差原则,对算法的配准效果做详细评估。仿真实验表明,该算法准确、快速,配准精度满足目标识别的要求,可以较好地解决异类传感器弱小目标图像配准的难题。 展开更多
关键词 仿 仿
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Deformation patterns of steel targets against long rod penetration
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作者 Chengxin Du Peng Wang +4 位作者 Bingnan Xing Feng Zhou Wenzheng Lv Zhonghua Du Guangfa Gao 《Defence Technology(防务技术)》 2025年第8期272-287,共16页
An experimental and finite element simulation investigation are conducted to study the deformation patterns of steel targets during the penetration process of tungsten alloy long rods,as well as the influence of stren... An experimental and finite element simulation investigation are conducted to study the deformation patterns of steel targets during the penetration process of tungsten alloy long rods,as well as the influence of strength of the target on the deformation patterns.The experimental results revealed slight mass loss in the first layer of the steel target during the transient entrance phase,with an extremely negligible loss in target mass during the quasi-steady penetration phase.The results of macro-analysis,micro-analysis and simulation show that the eroded target material migrated towards the periphery of the crater,causing an increase in the target's thickness,remained within the target,instead of flowing out of the crater.Therefore,the process of long rods penetrating the metal target is considered as a process of backward extrusion.By combining the backward extrusion theory with energy conservation,a penetration depth model for long rods penetrating a metal target,taking into account both the diameter of the crater and the friction coefficient between the rod and the target,has been established.Although the model is not yet perfect,it innovatively applies the principles of solid mechanics to the study of long rod penetration.Additionally,it takes into account the friction coefficient between the rod and the target during the penetration process.Therefore,this model provides a new research direction for future studies on long rod penetration. 展开更多
关键词 Long-rod penetration Mass loss of target Deformation patterns of targets Penetration depth model Backward extrusion theory
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从海拉尔盆地勘探历程看大庆外围中小型盆地勘探前景 被引量:7
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作者 孟祥军 金成志 +2 位作者 杨平 霍凤龙 吴宏军 《中国石油勘探》 CAS 2005年第3期22-25,45,共5页
通过对海拉尔盆地勘探历程的总结,阐述了断陷盆地勘探的四个特点,即盆地勘探突破需要一定的前期投入准备和具有较长的储备时间,勘探工程量投入与勘探成果呈正相关性,盆地勘探的突破与三维地震量的加大同步,资源量的认识在勘探的不同阶... 通过对海拉尔盆地勘探历程的总结,阐述了断陷盆地勘探的四个特点,即盆地勘探突破需要一定的前期投入准备和具有较长的储备时间,勘探工程量投入与勘探成果呈正相关性,盆地勘探的突破与三维地震量的加大同步,资源量的认识在勘探的不同阶段存在一个较大的变动过程;分析了断陷盆地勘探所需历经的地震勘探准备阶段,系统研究、准确定位阶段,以及加大三维地震、钻井工作量,勘探从发现到突破阶段等三个阶段;得出了工程量的投入是勘探突破的保障,二维地震是勘探发现的基础、三维地震是勘探突破的关键,断陷盆地资源量的认识与钻探程度密切相关等三个结论。以此为模式,类比并提出了三江、漠河、大杨树、依兰—舒兰、孙吴—嘉荫等大庆外围中小型盆地具有较好的勘探前景。 展开更多
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Impact time control guidance for moving-target considering velocity variation and field-of-view constraint
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作者 YANG Hao ZHANG Shifeng +1 位作者 BAI Xibin YANG Chengye 《Journal of Systems Engineering and Electronics》 2025年第2期552-568,共17页
In the existing impact time control guidance (ITCG) laws for moving-targets, the effects of time-varying velocity caused by aerodynamics and gravity cannot be effectively con-sidered. Therefore, an ITCG with field-of-... In the existing impact time control guidance (ITCG) laws for moving-targets, the effects of time-varying velocity caused by aerodynamics and gravity cannot be effectively con-sidered. Therefore, an ITCG with field-of-view (FOV) constraints based on biased proportional navigation guidance (PNG) is developed in this paper. The remaining flight time (time-to-go) estimation method is derived considering aerodynamic force and gravity. The number of differential equations is reduced and the integration step is increased by changing the integral variable, which makes it possible to obtain time-to-go through integration. An impact time controller with FOV constraints is proposed by analyzing the influence of the biased term on time-to-go and FOV constraint. Then, numerical simulations are performed to verify the correctness and superiority of the method. 展开更多
关键词 moving target time-varying velocity time-to-go esti-mation field-of-view(FOV)constraint flight time control.
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阿尔金山东南缘构造特征及勘探前景 被引量:4
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作者 康南昌 覃素华 +1 位作者 陈元忠 管俊亚 《石油地球物理勘探》 EI CSCD 北大核心 2005年第2期233-237,242,共6页
柴达木盆地阿尔金山东南缘地质历史上经历了多期构造运动,构造复杂。本文通过对断裂、构造样式等的研究表明,阿尔金山东南缘逆断层发育,形成向阿尔金山前散开、向盆内收敛的“帚状”分布;在这些压剪性断层控制下形成了一系列断鼻及多种... 柴达木盆地阿尔金山东南缘地质历史上经历了多期构造运动,构造复杂。本文通过对断裂、构造样式等的研究表明,阿尔金山东南缘逆断层发育,形成向阿尔金山前散开、向盆内收敛的“帚状”分布;在这些压剪性断层控制下形成了一系列断鼻及多种构造样式,造成深浅层构造存在较大的差异。通过对烃源岩、储集层和盖层的综合分析评价认为,该区生储盖条件较好,侏罗系具有一定的生烃潜力,圈闭发育,油气藏类型丰富,有较大的勘探潜力。 展开更多
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