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基于改进RTAB-Map算法的爬壁机器人导航研究
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作者 覃超 唐东林 +3 位作者 游东潘 丁超 饶胜 何媛媛 《工程设计学报》 北大核心 2025年第1期32-41,共10页
针对爬壁机器人难以对大型石化装备壁面感知和自动化检测等难题,提出了一种改进RTAB-Map(real-time appearance-based mapping,基于外观的实时建图)算法,通过多传感器数据融合实现爬壁机器人定位、建图与导航。首先,搭建了具有壁面吸附... 针对爬壁机器人难以对大型石化装备壁面感知和自动化检测等难题,提出了一种改进RTAB-Map(real-time appearance-based mapping,基于外观的实时建图)算法,通过多传感器数据融合实现爬壁机器人定位、建图与导航。首先,搭建了具有壁面吸附能力的机器人运动底盘,以保证爬壁机器人在壁面灵活稳定运动;其次,针对爬壁机器人在壁面滑移导致的里程计累计误差问题,采用扩展卡尔曼滤波并融合编码器和惯性测量单元的数据,为建图和导航提供精确的里程计信息;再次,基于RTAB-Map算法对深度相机、激光雷达及里程计的数据进行融合,生成二维栅格和三维点云地图,实现对装备壁面的完整描述,并基于融合数据构建了爬壁机器人导航算法的框架;最后,在装备壁面进行了实验验证。结果表明:采用融合里程计算法,能显著减小航向角误差,航向角平均误差为0.78°,相对轮式里程计规划,航向角误差减少了88.94%;改进RTAB-Map算法提高了爬壁机器人在壁面环境下的建图与感知能力,结合路径规划算法,实现了机器人自主导航。研究结果对爬壁机器人自动化检测技术的研究及应用具有一定的参考意义。 展开更多
关键词 爬壁机器人 RTAB-map(基于外观的实时建图)算法 扩展卡尔曼滤波 多传感器融合 导航
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MUSE-IVIM与非对比增强T1 mapping定量参数对肝癌经导管动脉化疗栓塞疗效的预测价值
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作者 董亚宁 朱菊芳 +3 位作者 段金辉 任继鹏 毛珂 韩东明 《医学影像学杂志》 2025年第6期82-86,共5页
目的探讨基于复合灵敏度编码的体素不相干运动(MUSE-IVIM)与非对比增强T1 mapping定量参数对肝癌经导管动脉化疗栓塞(TACE)疗效的预测价值。方法选取原发性肝癌患者64例,TACE治疗后随访3~6个月,根据改良实体瘤疗效评估标准分为良好反应... 目的探讨基于复合灵敏度编码的体素不相干运动(MUSE-IVIM)与非对比增强T1 mapping定量参数对肝癌经导管动脉化疗栓塞(TACE)疗效的预测价值。方法选取原发性肝癌患者64例,TACE治疗后随访3~6个月,根据改良实体瘤疗效评估标准分为良好反应组28例、较差反应组36例。TACE治疗前1~2周行MUSE-IVIM及T1 mapping扫描,获取MUSE-IVIM定量参数标准表观扩散系数(standard ADC)值、慢速表观扩散系数(slow ADC)值、快速表观扩散系数(fast ADC)值以及灌注分数(f)值、水分子扩散分布指数(DDC)值和扩散异质性指数(α)值,T1 mapping定量参数初始瘤内与瘤周纵向弛豫时间(T1)值。比较两组MUSE-IVIM及T1 mapping定量参数,采用多因素Logistic回归模型筛选与肝癌TACE疗效相关的危险因素,预测效能评估采用受试者工作特征(ROC)曲线。结果两组MUSE-IVIM定量参数standard ADC值和slow ADC值比较差异均有统计学意义(P均<0.05),而MUSE-IVIM定量参数fast ADC值、f值、DDC值、α值及初始瘤内T1值、初始瘤周T1值比较差异均无统计学意义(P均>0.05)。多因素Logistic回归分析发现standard ADC值、slow ADC值均为预测肝癌TACE疗效的独立危险因素(P均<0.05)。ROC曲线分析显示standard ADC值、slow ADC值及二者联合预测肝癌TACE疗效的曲线下面积(AUC)分别为0.85、0.86、0.89,虽然显示standard ADC值、slow ADC值联合预测肝癌TACE疗效的AUC高于二者单独,但其比较差异无统计学意义(P均>0.05)。结论MUSE-IVIM定量参数standard ADC值和slow ADC值对肝癌TACE疗效具有较好的预测价值,而非对比增强T1 mapping技术不能很好地预测肝癌TACE疗效。 展开更多
关键词 磁共振成像 基于复合灵敏度编码的体素不相干运动成像 非对比增强T1 mapping成像 肝癌 经导管动脉化疗栓塞术
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Use of GIS Based Maps for Preliminary Assessment of Subsoil of Guwahati City 被引量:1
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作者 Binu Sharma Shaffi Kamal Rahman 《Journal of Geoscience and Environment Protection》 2016年第5期106-116,共11页
Guwahati, the major city in the North Eastern region of India is growing rapidly in every aspect with major infrastructures like sports complex, educational institutions, hospitals, flyovers, multiplex halls, etc. Kno... Guwahati, the major city in the North Eastern region of India is growing rapidly in every aspect with major infrastructures like sports complex, educational institutions, hospitals, flyovers, multiplex halls, etc. Knowledge of the subsurface soil condition is necessary to ensure the structural safety and serviceability of the above mentioned structures before any construction. Therefore, contour maps of Standard penetration test N value, ground water table and shear wave velocity map using Geographical Information System (GIS) platform will be of great help to the foundation designers at the initial stage for site selection and preliminary foundation design under static and seismic condition. Contour maps of Standard penetration test N value at different depth and average contour map of N value of Guwahati city have been prepared. Standard penetration Test N values and depth of water table were taken from a data base of 200 boreholes up to 30 meter depth to prepare N value contour map of Guwahati city. A regression equation between shear wave velocity V<sub>s</sub> and Standard penetration test N value based on twenty seven previous similar correlations was also developed. This regression equation was used to determine shear wave velocity of Guwahati city. The average shear wave velocities for 30 m depth for all locations had been determined and used to generate map on (GIS) platform. Other subsurface geotechnical information of Guwahati city like soil classification and depth to water level from ground surface is also presented in the form of GIS based maps in order to form a data base. 展开更多
关键词 Standard Penetration Test Shear Wave Velocity Contour map GIS based maps Subsurface Investigation
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A MAP Approach for Vision-based Self-localization of Mobile Robot 被引量:3
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作者 WANG Ke WANG Wei ZHUANG Yan 《自动化学报》 EI CSCD 北大核心 2008年第2期159-166,共8页
一当场,自我本地化系统为在有深入的 3D 里程碑的 3D 环境起作用的活动机器人被开发。机器人通过合并从 odometry 和单向性的照相机收集的信息的一个地图评估者递归地估计它的姿势。我们为这二个传感器造非线性的模型并且坚持说机器人... 一当场,自我本地化系统为在有深入的 3D 里程碑的 3D 环境起作用的活动机器人被开发。机器人通过合并从 odometry 和单向性的照相机收集的信息的一个地图评估者递归地估计它的姿势。我们为这二个传感器造非线性的模型并且坚持说机器人运动和不精密的传感器大小的无常操作应该全部被嵌入并且追踪我们的系统。我们在一个概率的几何学观点和使用 unscented 变换描述无常框架宣传无常,它经历给定的非线性的功能。就我们的机器人的处理力量而言,图象特征在相应投射特征的附近被提取。另外,数据协会被统计距离评估。最后,一系列系统的实验被进行证明我们的系统的可靠、精确的性能。 展开更多
关键词 map估计 自动定位 视觉 移动式遥控装置 不确定传播 传感器
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QTL Mapping for Fiber Quality Traits Based on a Dense Genetic Linkage Map with SSR,TRAP,SRAP and AFLP Markers in Cultivated Tetraploid Cotton 被引量:1
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作者 YU Ji-wen1,YU Shu-xun1,ZHANG Jin-fa2,ZHAI Hong-hong1(1.Cotton Research Institute of CAAS Key Laboratory of Cotton Genetic Improvement,Ministry of Agriculture,Anyang,Henan 455000,China 2.Department of Plant and Environmental Sciences,New Mexico State University,Las Cruces,NM 88003) 《棉花学报》 CSCD 北大核心 2008年第S1期34-,共1页
Cotton is one of the most important economic crops in the world,and it provides natural fiber for the textile industry.With the advancement of the textile technology and increased consumption demands on cotton fiber,b... Cotton is one of the most important economic crops in the world,and it provides natural fiber for the textile industry.With the advancement of the textile technology and increased consumption demands on cotton fiber,both cotton yield and quality should be enhanced.However,cotton yield 展开更多
关键词 QTLs AFLP QTL mapping for Fiber Quality Traits based on a Dense Genetic Linkage map with SSR TRAP SRAP and AFLP Markers in Cultivated Tetraploid Cotton SSR map
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Hot deformation of spray formed nickel-base superalloy using processing maps 被引量:8
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作者 康福伟 张国庆 +1 位作者 李周 孙剑飞 《中国有色金属学会会刊:英文版》 EI CSCD 2008年第3期531-535,共5页
The hot compression testing of hot isostatically pressed(HIPed) spray formed(SF) nickel-base superalloy was carried out by thermal mechanical simulator in the temperature range of 1 050-1 140 ℃ at strain rates of 0.0... The hot compression testing of hot isostatically pressed(HIPed) spray formed(SF) nickel-base superalloy was carried out by thermal mechanical simulator in the temperature range of 1 050-1 140 ℃ at strain rates of 0.01-10 s-1 and engineering strain of 50%. A processing map was developed on the basis of these data by using the principles of dynamic materials modeling. The microstructural evolution of deformed samples was also examined on the basis of optical and electron microscopic observations. The map exhibits two domains: the instability domain at the temperatures of 1 050 ℃ -1 110 ℃ and strain rate of 0.01 s-1, the stability domain at the temperatures of 1 110 ℃- 1 140 ℃ and strain rates of 1 s-1-10 s-1, with a peak efficiency of about 40%. The dynamic recrystallization(DRX) is observed in the stability domain and the deformed specimens are no cracking or instabilities. However, there is no DRX in the instability domain and the alloy exhibits flow instability with cracks due to poor workability. The optimum hot working condition was determined in the stability domain. 展开更多
关键词 喷溅成型 高温合金 加工处理 重结晶
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3DV quality model based depth maps for view synthesis in FTV system
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作者 张秋闻 安平 +2 位作者 张艳 张兆杨 王元庆 《Journal of Shanghai University(English Edition)》 CAS 2011年第4期335-341,共7页
Depth maps are used for synthesis virtual view in free-viewpoint television (FTV) systems. When depth maps are derived using existing depth estimation methods, the depth distortions will cause undesirable artifacts ... Depth maps are used for synthesis virtual view in free-viewpoint television (FTV) systems. When depth maps are derived using existing depth estimation methods, the depth distortions will cause undesirable artifacts in the synthesized views. To solve this problem, a 3D video quality model base depth maps (D-3DV) for virtual view synthesis and depth map coding in the FTV applications is proposed. First, the relationships between distortions in coded depth map and rendered view are derived. Then, a precisely 3DV quality model based depth characteristics is develop for the synthesized virtual views. Finally, based on D-3DV model, a multilateral filtering is applied as a pre-processed filter to reduce rendering artifacts. The experimental results evaluated by objective and subjective methods indicate that the proposed D-3DV model can reduce bit-rate of depth coding and achieve better rendering quality. 展开更多
关键词 free-viewpoint television (FTV) 3D video quality model base depth maps (D-3DV) view synthesis
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Ciphertext-Policy Attribute-Based Encryption for General Circuits from Bilinear Maps 被引量:2
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作者 HU Peng GAO Haiying 《Wuhan University Journal of Natural Sciences》 CAS CSCD 2017年第2期171-177,共7页
In this paper, we present the first ciphertext-policy attribute-based encryption (CP-ABE) scheme for polynomial-size general circuits based on bilinear maps which is more suitable for practical use and more efficien... In this paper, we present the first ciphertext-policy attribute-based encryption (CP-ABE) scheme for polynomial-size general circuits based on bilinear maps which is more suitable for practical use and more efficient than multilinear maps. Our scheme uses a top-down secret sharing and FANOUT gate to resist the "backtracking attack" which is the main barrier expending access tree to general circuit. In the standard model, selective security of our scheme is proved. Comparing with current scheme for general circuits from bilinear maps, our work is more efficient. 展开更多
关键词 ciphertext-policy attribute-based encryption general circuits bilinear maps selective security
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Neuronal injury in the motor cortex after chronic stroke and lower limb motor impairment: a voxelbased lesion symptom mapping study 被引量:1
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作者 Alexandria M.Reynolds Denise M.Peters +5 位作者 Jennifer M.C.Vendemia Lenwood P.Smith Raymond C.Sweet Gordon C.Baylis Debra Krotish Stacy L.Fritz 《Neural Regeneration Research》 SCIE CAS CSCD 2014年第7期766-772,共7页
Many studies have examined motor impairments using voxel-based lesion symptom mapping, but few are reported regarding the corresponding relationship between cerebral cortex injury and lower limb motor impairment analy... Many studies have examined motor impairments using voxel-based lesion symptom mapping, but few are reported regarding the corresponding relationship between cerebral cortex injury and lower limb motor impairment analyzed using this technique. This study correlated neuro- nal injury in the cerebral cortex of 16 patients with chronic stroke based on a voxel-based lesion symptom mapping analysis. Neuronal injury in the corona radiata, caudate nucleus and putamen of patients with chronic stroke could predict walking speed. The behavioral measure scores were consistent with motor deficits expected after damage to the cortical motor system due to stroke. These findings suggest that voxel-based lesion symptom mapping may provide a more accurate prognosis of motor recovery from chronic stroke according to neuronal injury in cerebral motor cortex. 展开更多
关键词 nerve regeneration magnetic resonance imaging STROKE cerebral cortex motor cortex voxel-based lesion symptom mapping motor function PROGNOSIS neural regeneration
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Variable-Coefficient Mapping Method Based on Elliptical Equation and Exact Solutions to Nonlinear SchrSdinger Equations with Variable Coefficient
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作者 GE Jian-Ya WANG Rui-Min +1 位作者 DAI Chao-Qing ZHANG Jie-Fang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第4X期656-662,共7页
In this paper, by means of the variable-coefficient mapping method based on elliptical equation, we obtain explicit solutions of nonlinear Schrodinger equation with variable-coefficient. These solutions include Jacobi... In this paper, by means of the variable-coefficient mapping method based on elliptical equation, we obtain explicit solutions of nonlinear Schrodinger equation with variable-coefficient. These solutions include Jacobian elliptic function solutions, solitary wave solutions, soliton-like solutions, and trigonometric function solutions, among which some are found for the first time. Six figures are given to illustrate some features of these solutions. The method can be applied to other nonlinear evolution equations in mathematical physics. 展开更多
关键词 variable-coefficient mapping method based on elliptical equation nonlinear Schrodinger equation Jacobian elliptic function solutions solitonic solutions trigonometric function solutions
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Mineral Prospectivity Mapping Method Integrating Multi-Sources Geology Spatial Data Sets and Case-Based Reasoning 被引量:1
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作者 Binbin He Jianhua Chen +1 位作者 Cuihua Chen Yue Liu 《Journal of Geographic Information System》 2012年第2期77-85,共9页
Extracting and synthesizing information from existing and massive amounts of geology spatial data sets is of great scientific significance and has considerable value in its applications. To make mineral exploration le... Extracting and synthesizing information from existing and massive amounts of geology spatial data sets is of great scientific significance and has considerable value in its applications. To make mineral exploration less expensive, more efficient, and more accurate, it is important to move beyond traditional concepts and establish a rapid, efficient, and intelligent method of predicting the existence and location of minerals. This paper describes a case-based reasoning (CBR) method for mineral prospectivity mapping that takes spatial features of geology data into account and offers an intelligent approach. This method include a metallogenic case representation that combines spatial and attribute features, metallogenic case-based storage organization, and a metallogenic case similarity retrieval model. The experiments were performed in the eastern Kunlun Mountains, China using CBR and weights-of-evidence (WOE), respectively. The results show that the prediction accuracy of the CBR is higher than that of the WOE. 展开更多
关键词 MINERAL Prospectivity mapping Case-based Reasoning METALLOGENIC CASE Representation METALLOGENIC CASE Retrieval Eastern KUNLUN MOUNTAINS
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Research on Ubiquitous Map Information Organization Oriented to Location-Based Aggregation
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作者 Si Wang Guangxia Wang 《Journal of Geoscience and Environment Protection》 2022年第1期238-249,共12页
<div style="text-align:justify;"> In the era of information and communication technology (ICT) and big data, the map gradually shows a new qualitative feature of “spatiotemporal ubiquitous” due to th... <div style="text-align:justify;"> In the era of information and communication technology (ICT) and big data, the map gradually shows a new qualitative feature of “spatiotemporal ubiquitous” due to the extension of its object space and the geographic information it contains, which brings new challenges to map information organization. This paper analyzes the concept and information characteristics of the ubiquitous map. Based on that, it proposes a ubiquitous map information organization model oriented to location-based aggregation. This new model includes three parts as “ubiquitous map instance”, “location-based aggregation mode” and “map scene”. This paper focuses on the “map scene” part which is the core of the model and contains two mutually mapped aspects as “content scene” and “representation scene”. And both aspects are divided into three levels as “features” ←→ “elements” ←→ “scenes” according to ubiquitous map information characteristics and location-based aggregation mode. With cases of map decomposition, the application of the model is explained to illustrate its effectiveness. The model is expected to provide powerful data organization and management capabilities for ubiquitous map production and use. </div> 展开更多
关键词 Ubiquitous map Information Organization Location-based Aggregation map Scene
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An optical modulation format generation scheme based on spectral filtering and frequency-to-time mapping
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作者 张爱玲 张悦 +2 位作者 宋红云 姚远 潘洪刚 《Optoelectronics Letters》 EI 2018年第1期36-39,共4页
An optical modulation format generation scheme based on spectral filtering and frequency-to-time mapping is experimentally demonstrated. Many modulation formats with continuously adjustable duty radio and bit rate can... An optical modulation format generation scheme based on spectral filtering and frequency-to-time mapping is experimentally demonstrated. Many modulation formats with continuously adjustable duty radio and bit rate can be formed by changing the dispersion of dispersion element and the bandwidth of shaped spectrum in this scheme. In the experiment, non-return-to-zero(NRZ) signal with bit rate of 29.41 Gbit/s and 1/2 duty ratio return-to-zero(RZ) signal with bit rate of 13.51 Gbit/s are obtained. The maximum bit rate of modulation format signal is also analyzed. 展开更多
关键词 NRZ An optical modulation format generation scheme based on spectral filtering and frequency-to-time mapping
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MAP-based Audio Coding Compensation for Speaker Recognition
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作者 Tao Jiang Jiqing Han 《Journal of Signal and Information Processing》 2011年第3期165-169,共5页
The performance of the speaker recognition system declines when training and testing audio codecs are mismatched. In this paper, based on analyzing the effect of mismatched audio codecs in the linear prediction cepstr... The performance of the speaker recognition system declines when training and testing audio codecs are mismatched. In this paper, based on analyzing the effect of mismatched audio codecs in the linear prediction cepstrum coefficients, a method of MAP-based audio coding compensation for speaker recognition is proposed. The proposed method firstly sets a standard codec as a reference and trains the speaker models in this codec format, then learns the deviation distributions between the standard codec format and the other ones, next gets the current bias via using a small number adaptive data and the MAP-based adaptive technique, and then adjusts the model parameters by the type of coming audio codec format and its related bias. During the test, the features of the coming speaker are used to match with the adjusted model. The experimental result shows that the accuracy reached 82.4% with just one second adaptive data, which is higher 5.5% than that in the baseline system. 展开更多
关键词 AUDIO CODING COMPENSATION SPEAKER RECOGNITION map-based
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Object-based image analysis for mapping geomorphic zones of coral reefs in the Xisha Islands, China 被引量:7
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作者 XU Jingping ZHAO Jianhua +5 位作者 LI Fang WANG Lin SONG Derui WEN Shiyong WANG Fei GAO Ning 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2016年第12期19-27,共9页
Mapping regional spatial patterns of coral reef geomorphology provides the primary information to understand the constructive processes in the reef ecosystem. However, this work is challenged by the pixel-based image ... Mapping regional spatial patterns of coral reef geomorphology provides the primary information to understand the constructive processes in the reef ecosystem. However, this work is challenged by the pixel-based image classification method for its comparatively low accuracy. In this paper, an object-based image analysis(OBIA)method was presented to map intra-reef geomorphology of coral reefs in the Xisha Islands, China using Landsat 8satellite imagery. Following the work of the Millennium Coral Reef Mapping Project, a regional reef class hierarchy with ten geomorphic classes was first defined. Then, incorporating the hierarchical concept and integrating the spectral and additional spatial information such as context, shape and contextual relationships, a large-scale geomorphic map was produced by OBIA with accuracies generally more than 80%. Although the robustness of OBIA has been validated in the applications of coral reef mapping from individual reefs to reef system in this paper, further work is still required to improve its transferability. 展开更多
关键词 object-based Landsat 8 geomorphic mapping Xisha Islands
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METHOD OF HIGH-LEVEL TECHNOLOGY MAPPING BASED ON KNOWLEDGE(RULE)
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作者 Ma Cong Wang Zuojian Liu Mingye (ASIC research Center of Beijing Institute of Technology, Beijing 100081) 《Journal of Electronics(China)》 2001年第1期24-31,共8页
This paper studies the linkage problem between the result of high-level synthesis and back-end technology, presents a method of high-level technology mapping based on knowl edge, and studies deeply all of its importan... This paper studies the linkage problem between the result of high-level synthesis and back-end technology, presents a method of high-level technology mapping based on knowl edge, and studies deeply all of its important links such as knowledge representation, knowledge utility and knowledge acquisition. It includes: (1) present a kind of expanded production about knowledge of circuit structure; (2) present a VHDL-based method to acquire knowledge of tech nology mapping; (3) provide solution control strategy and algorithm of knowledge utility; (4)present a half-automatic maintenance method, which can find redundance and contradiction of knowledge base; (5) present a practical method to embed the algorithm into knowledge system to decrease complexity of knowledge base. A system has been developed and linked with three kinds of technologies, so verified the work of this paper. 展开更多
关键词 HIGH-LEVEL synthesis TECHNOLOGY mapping VHDL HIGH-LEVEL TECHNOLOGY map PING KNOWLEDGE base KNOWLEDGE representation
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Correction of Inertial Navigation System’s Errors by the Help of Video-Based Navigator Based on Digital Terrarium Map
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作者 Oleg Yurjevich Kupervasser Alexander Alexandrovich Rubinstein 《Positioning》 2013年第1期89-108,共20页
This paper deals with the error analysis of a novel navigation algorithm that uses as input the sequence of images acquired from a moving camera and a Digital Terrain (or Elevation) Map (DTM/DEM). More specifically, i... This paper deals with the error analysis of a novel navigation algorithm that uses as input the sequence of images acquired from a moving camera and a Digital Terrain (or Elevation) Map (DTM/DEM). More specifically, it has been shown that the optical flow derived from two consecutive camera frames can be used in combination with a DTM to estimate the position, orientation and ego-motion parameters of the moving camera. As opposed to previous works, the proposed approach does not require an intermediate explicit reconstruction of the 3D world. In the present work the sensitivity of the algorithm outlined above is studied. The main sources for errors are identified to be the optical-flow evaluation and computation, the quality of the information about the terrain, the structure of the observed terrain and the trajectory of the camera. By assuming appropriate characterization of these error sources, a closed form expression for the uncertainty of the pose and motion of the camera is first developed and then the influence of these factors is confirmed using extensive numerical simulations. The main conclusion of this paper is to establish that the proposed navigation algorithm generates accurate estimates for reasonable scenarios and error sources, and thus can be effectively used as part of a navigation system of autonomous vehicles. 展开更多
关键词 Video-based NAVIGATOR Digital Terrarium map Autonomous Vehicles INERTIAL Navigation
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基于地基云图数据多维特征融合的光伏功率预测算法 被引量:1
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作者 吐松江·卡日 吴现 +3 位作者 马小晶 雷柯松 余凯峰 司伟壮 《电力系统保护与控制》 北大核心 2025年第11期84-94,共11页
针对传统光伏功率预测算法无法获取准确云层状态信息和预测精度低等问题,提出一种基于地基云图与双流数据融合的光伏功率预测算法。首先,利用地基云图提供的精确云层状态信息,结合稠密光流法获取相邻帧图像间的时空特征与细节变化特征... 针对传统光伏功率预测算法无法获取准确云层状态信息和预测精度低等问题,提出一种基于地基云图与双流数据融合的光伏功率预测算法。首先,利用地基云图提供的精确云层状态信息,结合稠密光流法获取相邻帧图像间的时空特征与细节变化特征。其次,结合卷积神经网络(convolutional neural network,CNN)在特征提取上的优势和残差网络在模型学习中抑制信息丢失上的优势,提升预测模型对光伏功率与图像数据间长期映射关系的学习能力。此外,引入注意力机制弥补模型训练过程中关键信息利用不充分的缺陷。实验结果表明,地基云图与光流数据的加入为多云天气提供了更多时空特征。与基准模型相比,其晴天与多云情况下均方根误差(root mean squared error,RMSE)指标和平均绝对误差(mean absolute error,MAE)指标分别降低了15.50%、11.65%、4.05%与5.15%,有助于充分利用云层运动状况来实现准确可靠的光伏电站输出功率预测,提升光伏电站调度工作的及时性与准确性。 展开更多
关键词 深度学习 功率预测 地基云图 注意力机制 稠密光流算法
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基于自然的解决方案在中国的研究进展与趋势 被引量:1
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作者 刘世梁 董玉红 +1 位作者 王军 王菀婷 《测绘科学》 北大核心 2025年第1期10-20,共11页
针对基于自然的解决方案(NbS)理念在生态文明建设中的重大需求,仍存在与国外研究相脱节、国内的研究进展和发展趋势需要梳理的问题,基于文献计量学的方法,利用中国知网数据库,对相关研究进行了梳理,揭示了该领域的研究焦点、热门主题、... 针对基于自然的解决方案(NbS)理念在生态文明建设中的重大需求,仍存在与国外研究相脱节、国内的研究进展和发展趋势需要梳理的问题,基于文献计量学的方法,利用中国知网数据库,对相关研究进行了梳理,揭示了该领域的研究焦点、热门主题、演进趋势等。研究表明NbS呈现快速增长趋势,自然资源部国土整治中心、北京大学等机构在NbS研究中发挥了重要作用。NbS和生态修复、生物多样性、绿色基础设施和生态文明关联紧密,形成不同主题团簇,Citespace聚类分为生态修复、城市韧性、自然教育、碳中和、中国、途径和生境营造,相关研究尺度逐步扩展,从绿色基础设施发展到应对自然灾害、气候变化和双碳目标等。本文揭示了NbS的研究进展与趋势,探讨面临的挑战和发展方向,为推动相关实践和政策制定提供依据。 展开更多
关键词 基于自然的解决方案 知识图谱 评估指标 生态修复 文献计量
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以CBL教学法为基础的思维导图在临床教学中的应用进展 被引量:1
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作者 张静 曾萍 +2 位作者 黄萃园 李文强 杨简 《中国继续医学教育》 2025年第3期81-84,共4页
医学是将理论与实践密切关联的学科,医学生在临床实习阶段面临着将理论应用于实践的挑战。随着医学教育的发展,以案例教学法(case-based learning,CBL)为基础的思维导图逐渐成为临床教学的重要模式,其注重于对学生的临床理论、技能操作... 医学是将理论与实践密切关联的学科,医学生在临床实习阶段面临着将理论应用于实践的挑战。随着医学教育的发展,以案例教学法(case-based learning,CBL)为基础的思维导图逐渐成为临床教学的重要模式,其注重于对学生的临床理论、技能操作以及临床思维的培养,通过引入真实的临床案例,融合理论知识和实践经验,使抽象的理论更加清晰形象。文章就以CBL教学法为基础的思维导图教学在临床教学中的应用概况做一综述,探讨CBL教学法对学生临床理论知识和实践操作能力的提升,强调思维导图在思维整合和可视化方面的作用,进一步讨论CBL教学法与思维导图的结合应用,指出该教学模式有助于学生的临床思维及临床实践能力的提升,旨在为指导临床教学实践,提高教学效果,培养高素质的临床医生提供借鉴和参考。 展开更多
关键词 临床教学 案例教学法 思维导图 病例讨论 知识整合 实践操作技能
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