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MKEAH:Multimodal knowledge extraction and accumulation based on hyperplane embedding for knowledge-based visual question answering
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作者 Heng ZHANG Zhihua WEI +6 位作者 Guanming LIU Rui WANG Ruibin MU Chuanbao LIU Aiquan YUAN Guodong CAO Ning HU 《虚拟现实与智能硬件(中英文)》 EI 2024年第4期280-291,共12页
Background External knowledge representations play an essential role in knowledge-based visual question and answering to better understand complex scenarios in the open world.Recent entity-relationship embedding appro... Background External knowledge representations play an essential role in knowledge-based visual question and answering to better understand complex scenarios in the open world.Recent entity-relationship embedding approaches are deficient in representing some complex relations,resulting in a lack of topic-related knowledge and redundancy in topic-irrelevant information.Methods To this end,we propose MKEAH:Multimodal Knowledge Extraction and Accumulation on Hyperplanes.To ensure that the lengths of the feature vectors projected onto the hyperplane compare equally and to filter out sufficient topic-irrelevant information,two losses are proposed to learn the triplet representations from the complementary views:range loss and orthogonal loss.To interpret the capability of extracting topic-related knowledge,we present the Topic Similarity(TS)between topic and entity-relations.Results Experimental results demonstrate the effectiveness of hyperplane embedding for knowledge representation in knowledge-based visual question answering.Our model outperformed state-of-the-art methods by 2.12%and 3.24%on two challenging knowledge-request datasets:OK-VQA and KRVQA,respectively.Conclusions The obvious advantages of our model in TS show that using hyperplane embedding to represent multimodal knowledge can improve its ability to extract topic-related knowledge. 展开更多
关键词 knowledge-based visual question answering HYPERPLANE Topic-related
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基于Photo Sphere Viewer的轻量化可量测街景系统研究
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作者 刘一宁 王琳 岳照溪 《测绘通报》 CSCD 北大核心 2024年第S01期11-17,共7页
随着新型基础测绘体系发展,测绘技术和装备不断升级,大量街景数据随着车载激光扫描工作一并被采集。针对该数据路线随机性大、密集程度高等特点,以及传统街景地图系统插件受限、扩展性不强、无法量测等局限,本文设计了基于Photo Sphere ... 随着新型基础测绘体系发展,测绘技术和装备不断升级,大量街景数据随着车载激光扫描工作一并被采集。针对该数据路线随机性大、密集程度高等特点,以及传统街景地图系统插件受限、扩展性不强、无法量测等局限,本文设计了基于Photo Sphere Viewer的轻量化可量测街景系统,在开源插件的基础上实现了对其组件的扩充、实现了行进方向、地图交互等系统功能的设计优化,进一步实现了基于深度图的街景地图量测功能。生产作业队伍对系统的使用结果表明,该系统可以辅助生产作业队伍进行属性采集、纹理更新、数据检查等多项工作,操作灵活便捷,且具有较强的可扩展性,便于基于生产需求进行改进调整,提高了生产效率,为新型基础测绘成果进一步深化应用提供了良好的借鉴作用。 展开更多
关键词 Photo Sphere viewer 轻量化 街景量测 街景数据组织 新型基础测绘
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Knowledge-Based Efficient N-1 Analysis Calculation Method for Urban Distribution Networks with CIM File Data
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作者 Lingyu Liang Xiangyu Zhao +3 位作者 Wenqi Huang Liming Sun Ziyao Wang Yaosen Zhan 《Energy Engineering》 EI 2023年第12期2839-2856,共18页
The N-1 criterion is a critical factor for ensuring the reliable and resilient operation of electric power distribution networks.However,the increasing complexity of distribution networks and the associated growth in ... The N-1 criterion is a critical factor for ensuring the reliable and resilient operation of electric power distribution networks.However,the increasing complexity of distribution networks and the associated growth in data size have created a significant challenge for distribution network planners.To address this issue,we propose a fast N-1 verification procedure for urban distribution networks that combines CIM file data analysis with MILP-based mathematical modeling.Our proposed method leverages the principles of CIM file analysis for distribution network N-1 analysis.We develop a mathematical model of distribution networks based on CIM data and transfer it into MILP.We also take into account the characteristics of medium voltage distribution networks after a line failure and select the feeder section at the exit of each substation with a high load rate to improve the efficiency of N-1 analysis.We validate our approach through a series of case studies and demonstrate its scalability and superiority over traditional N-1 analysis and heuristic optimization algorithms.By enabling online N-1 analysis,our approach significantly improves the work efficiency of distribution network planners.In summary,our proposed method provides a valuable tool for distribution network planners to enhance the accuracy and efficiency of their N-1 analyses.By leveraging the advantages of CIM file data analysis and MILP-based mathematical modeling,our approach contributes to the development of more resilient and reliable electric power distribution networks. 展开更多
关键词 MILP CIM fast analytical method N-1 distribution networks knowledge-based method
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Knowledge-based potentials in bioinformatics: From a physicist's viewpoint 被引量:1
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作者 郑伟谋 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第12期22-27,共6页
Biological raw data are growing exponentially, providing a large amount of information on what life is. It is believed that potential functions and the rules governing protein behaviors can be revealed from analysis o... Biological raw data are growing exponentially, providing a large amount of information on what life is. It is believed that potential functions and the rules governing protein behaviors can be revealed from analysis on known native structures of proteins. Many knowledge-based potentials for proteins have been proposed. Contrary to most existing review articles which mainly describe technical details and applications of various potential models, the main foci for the discussion here are ideas and concepts involving the construction of potentials, including the relation between free energy and energy, the additivity of potentials of mean force and some key issues in potential construction. Sequence analysis is briefly viewed from an energetic viewpoint. 展开更多
关键词 knowledge-based potentials for proteins protein native structures sequence signals
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基于单片机和LabVIEW的无线温度监测与控制系统设计
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作者 杨文宜 陈海滨 +1 位作者 徐东华 叶思灏 《广州航海学院学报》 2024年第2期75-78,共4页
本文设计了一个基于STC89C52单片机和LabVIEW的无线温度监测与控制系统.该系统采用上下位机的结构,其中下位机通过STC89C52单片机控制DS18B20采集实时温度,并利用控制模块实现加热或降温,同时,通过蓝牙模块实现与上位机的无线通信;上位... 本文设计了一个基于STC89C52单片机和LabVIEW的无线温度监测与控制系统.该系统采用上下位机的结构,其中下位机通过STC89C52单片机控制DS18B20采集实时温度,并利用控制模块实现加热或降温,同时,通过蓝牙模块实现与上位机的无线通信;上位机以LabVIEW作为开发平台,实现对温度的实时显示、处理、存储、阈值设定和温度控制等功能.该系统电路设计简单、成本低、扩展性强、人机界面友好,可用于智能大棚的温度控制等需要温度检测的场所,具有广阔的应用前景. 展开更多
关键词 温度采集 无线通信 Lab view
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Non-contact wide-field viewing system-assisted scleral buckling surgery for retinal detachment in silicone oilfilled eyes
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作者 Su-Lan Wu Yi-Qi Chen +7 位作者 Li-Jun Shen Jian-Bo Mao Li Lin Ji-Wei Tao Huan Chen Shi-An Zhang Jia-Feng Yu Chen-Xi Wang 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第4期761-766,共6页
AIM:To evaluate scleral buckling(SB)surgery using a noncontact wide-field viewing system and 23-gauge intraocular illumination for the treatment of rhegmatogenous retinal detachment in silicone oil(SO)-filled eyes.MET... AIM:To evaluate scleral buckling(SB)surgery using a noncontact wide-field viewing system and 23-gauge intraocular illumination for the treatment of rhegmatogenous retinal detachment in silicone oil(SO)-filled eyes.METHODS:Totally 9 patients(9 eyes)with retinal detachment in SO-filled eyes were retrospectively analyzed.All patients underwent non-contact wide-field viewing system-assisted buckling surgery with 23-gauge intraocular illumination.SO was removed at an appropriate time based on recovery.The patients were followed up for at least 3mo after SO removal.Retinal reattachment,complications,visual acuity and intraocular pressure(IOP)before and after surgery were observed.RESULTS:Patients were followed up for a mean of 8.22mo(3-22mo)after SO removal.All patients had retinal reattachment.At the final follow-up,visual acuity showed improvement for 8 patients,and no change for 1 patient.The IOP was high in 3 patients before surgery,but it stabilized after treatment;it was not affected in the other patients.None of the patients had infections,hemorrhage,anterior ischemia,or any other complication.CONCLUSION:This new non-contact wide-field viewing system-assisted SB surgery with 23-gauge intraocular illumination is effective and safe for retinal detachment in SO-filled eyes. 展开更多
关键词 non-contact wide-field viewing system scleral buckling silicone oil-filled retinal detachment
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A Brief Overview of the Development and Significance of Modern Scientific Medicine in China:Take Chinese Academy of Medical Science and Peking Union Medical College as an Example
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作者 Pu-An Cui Zhe-Xi Gong Zhong He 《Chinese Medical Sciences Journal》 CAS CSCD 2024年第2期140-143,共4页
Since the early 20th century,China has gradually established a clinical,educational,and research system centered around modern scientific medicine,which has now become the dominant force in China's medical and hea... Since the early 20th century,China has gradually established a clinical,educational,and research system centered around modern scientific medicine,which has now become the dominant force in China's medical and health system and services,with the construction and development of the Chinese Academy of Medical Sciences and Peking Union Medical College as the most prominent symbol.The scientific medicine in the new era requires close cooperation across multiple disciplines and fields to build a high-quality and efficient medical and health service system.It also involves combining the excellent traditional Chinese culture with Western medicine to explore a unique path of modern scientific medicine with Chinese characteristics. 展开更多
关键词 modern scientific medicine cultural confidence multiple view
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Research on Feature Matching Optimization Algorithm for Automotive Panoramic Surround View System
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作者 Guangbing Xiao Ruijie Gu +1 位作者 Ning Sun Yong Zhang 《Computer Systems Science & Engineering》 2024年第5期1329-1348,共20页
In response to the challenges posed by insufficient real-time performance and suboptimal matching accuracy of traditional feature matching algorithms within automotive panoramic surround view systems,this paper has pr... In response to the challenges posed by insufficient real-time performance and suboptimal matching accuracy of traditional feature matching algorithms within automotive panoramic surround view systems,this paper has proposed a high-performance dimension reduction parallel matching algorithm that integrates Principal Component Analysis(PCA)and Dual-Heap Filtering(DHF).The algorithm employs PCA to map the feature points into the lower-dimensional space and employs the square of Euclidean distance for feature matching,which significantly reduces computational complexity.To ensure the accuracy of feature matching,the algorithm utilizes Dual-Heap Filtering to filter and refine matched point pairs.To further enhance matching speed and make optimal use of computational resources,the algorithm introduces a multi-core parallel matching strategy,greatly elevating the efficiency of feature matching.Compared to Scale-Invariant Feature Transform(SIFT)and Speeded Up Robust Features(SURF),the proposed algorithm reduces matching time by 77%to 80%and concurrently enhances matching accuracy by 5%to 15%.Experimental results demonstrate that the proposed algorithmexhibits outstanding real-time matching performance and accuracy,effectivelymeeting the feature-matching requirements of automotive panoramic surround view systems. 展开更多
关键词 Featurematching automotive panoramic surround view system principal component analysis euclidean distance dual-heap filtering
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Window Views of Wards in Foreign Hospitals
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作者 LI Siyi SHAO Danjin WANG Xiaobo 《Journal of Landscape Research》 2024年第3期37-42,47,共7页
Through the collection and systematic analysis of documents related to window views of hospitals,it is found that natural window views had a significant impact on patients’health benefits.The research focused on thre... Through the collection and systematic analysis of documents related to window views of hospitals,it is found that natural window views had a significant impact on patients’health benefits.The research focused on three aspects:“shortening length of stay”,“pain reduction”and“improvement of recovery rate”,mainly covering three types of patients:“heart patients”,“postoperative patients”and“patients of rehabilitation centers”.Based on the above analysis,summary and sorting,new directions and perspectives of hospital environment design and research under the concept of comprehensive health of people’s physiological,psychological and social adaptation will be obtained to provide references for the research and practice of health architecture,rehabilitation architecture,biophile design and other fields. 展开更多
关键词 Window views Wards Research review Medical buildings Natural environment
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The Youth’s View of Marriage in Chinese Mainstream Media Discourse-A Corpus-assisted Three-dimensional Discourse Analysis
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作者 DING Shu-li LIN Ying 《Journal of Literature and Art Studies》 2024年第4期284-289,共6页
The rising of aging and the declining of birth rates have forced the public to focus on the youth’s view on marriage.Based on critical discourse analysis and combined with Fairclough’s three-dimensional discourse an... The rising of aging and the declining of birth rates have forced the public to focus on the youth’s view on marriage.Based on critical discourse analysis and combined with Fairclough’s three-dimensional discourse analysis model,this paper builds a“Chinese media News Report Corpus on the topic of‘marriage’”whose news are collected from China Daily.It is found that the discourses are neutral and objective with regard to the advantages and disadvantages of marriage,but in general,it is still a traditional view of marriage that is inevitable and closely related to fertility.Although this is controlled by the policies and the social reasons including declining fertility rate,it deviates from the current view of the youth towards marriage,resulting in many serious consequences such as young people’s rejection.In addition,this research found that male and female have great differences in their views on marriage,and men’s resistance to marriage is far greater than that of women,which is departure from the public’s cognition.The reasons behind this need to be explored in order to solve the marriage and love problems of young people in today’s era and realize the healthy development of young marriage. 展开更多
关键词 CORPORA Three-dimensional discourse analysis the youth’view of marriage
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Pragmatist View of Human Rights:Theoretical Explanations of China’s Human Rights Practice
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作者 YU Xiqiao GUO Dong 《The Journal of Human Rights》 2024年第3期614-636,共23页
The pragmatist view of human rights represents a the-oretical condensation of the Chinese practice in human rights devel-opment.In view of the problem of circular idling between rights and claims caused by the traditi... The pragmatist view of human rights represents a the-oretical condensation of the Chinese practice in human rights devel-opment.In view of the problem of circular idling between rights and claims caused by the traditional view of human rights of focusing on contents and not valuing implementation,social segmentation caused by empty talks on interests and claims while ignoring social develop-ment,and the phenomenon of the issue of human rights completely becoming empty and useless political rhetoric,the pragmatic view of human rights,based on the fact that there is a gap between the claims and realization of human rights,emphasizes that instead of blindly ex-panding the types of rights in term of text,it is better to base on prac-tice and promote the maximum realization of existing rights through development.The pragmatist view of human rights attaches impor-tance to relevant economic,social and cultural basis to promote the realization of human rights,rather than only focusing on the claims themselves;it pays greater attention to enhancing the realization of rights,rather than the distribution of rights under the total limit;it ad-vocates more for cooperativism in the realization of rights,rather than confrontation.The pragmatic concept of human rights takes Marxism as its theoretical basis and the gene of practice and the dimension of development as its theoretical characteristics,and promotes the devel-opment of human rights through the realization of rights. 展开更多
关键词 pragmatist view of human rights rights and claims realization of rights cooperativism development
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探究新课标下高中英语读思课中Viewing技能与学科素养的融合策略
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作者 华婕 《中国科技经济新闻数据库 教育》 2024年第5期0068-0070,共3页
本文率先介绍了Viewing渗透下高中英语阅读中的核心素养,再精准找出Viewing在高中英语读思课中的运用模块,然后全面探究出阅读思维和Viewing技能融合的有效策略,内容包含搭建多模态互动场景、丰富语言教学活动、科学运用思维导图及拓展... 本文率先介绍了Viewing渗透下高中英语阅读中的核心素养,再精准找出Viewing在高中英语读思课中的运用模块,然后全面探究出阅读思维和Viewing技能融合的有效策略,内容包含搭建多模态互动场景、丰富语言教学活动、科学运用思维导图及拓展英语阅读资源等,更好地培养学生的学习能力、语言能力、思维品质、文化意识与知识扩展能力,增强学生英语阅读综合素质。 展开更多
关键词 阅读思维 课文视图 英语阅读课 viewing渗透
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Analysis of Viewing Paintings from the Perspective of Iconography
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作者 Min Li 《Journal of Contemporary Educational Research》 2024年第7期297-303,共7页
Distinguished from purely formalistic research methods,iconography pursues the interpretation of the hidden historical and humanistic connotations behind artworks,and is a discipline that combines visual text and cont... Distinguished from purely formalistic research methods,iconography pursues the interpretation of the hidden historical and humanistic connotations behind artworks,and is a discipline that combines visual text and content analysis methods.Combining the three stages of iconography proposed by Panofsky,the paper studies Shizeng Chen’s Viewing Paintings from the perspective of iconography,summarizing the formation and change of the images and contents of the artworks in the cultural system and civilization at that time,as well as their implied ideology,and analyzing the hidden spirit of the times and the historical significance behind them,so as to expound their iconographic significance.Through an in-depth discussion at three levels:pre-pictorial iconographic description,iconographic analysis,and iconographic interpretation,the facts and surface contents reproduced in the images,the traditional level of literary,artistic,and cultural knowledge,as well as the interpretation of the potential meanings are revealed. 展开更多
关键词 ICONOGRAPHY viewing Paintings Spirit of the times Conceptual change
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Knowledge-Based Systems for the Assessment and Management of Bridge Structures: A Review
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作者 Ayaho Miyamoto 《Journal of Software Engineering and Applications》 2021年第10期505-536,共32页
It is becoming an important social problem to make maintenance and rehabilitation of existing infrastructures such as bridges, buildings, etc. in the world. The kernel of such structure management is to develop a meth... It is becoming an important social problem to make maintenance and rehabilitation of existing infrastructures such as bridges, buildings, etc. in the world. The kernel of such structure management is to develop a method of safety assessment on items<span style="font-family:;" "=""> </span><span style="font-family:;" "="">which include remaining life and load carrying capacity. The purpose of this paper is to summarize the finding of up-to-date research articles concerning the application of knowledge-based systems to assessment and management of structures and to illustrate the potential of such systems in the structural engineering. In here, knowledge-based systems include knowledge-based expert systems incorporation with artificial neural networks, fuzzy reasoning and genetic or immune algorithms.</span><span style="font-family:;" "=""> </span><span style="font-family:;" "="">Specifically, two modern bridge management systems (BMS’s) are presented in the paper. The first is a BMS to assess the performance and derive optimal strategies for inspection and maintenance of concrete bridge structures using reliability based and knowledge-based systems. The second is the concrete bridge rating expert system (<i>J-BMS BREX</i>) to evaluate the performance of existing bridges by incorporating with artificial neural networks and fuzzy reasoning.</span> 展开更多
关键词 knowledge-based System INFRASTRUCTURE BRIDGE Maintenance MANAGEMENT Expert System Reliability Neural Network Fuzzy Reasoning Genetic Algorithm
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Low-Rank Multi-View Subspace Clustering Based on Sparse Regularization
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作者 Yan Sun Fanlong Zhang 《Journal of Computer and Communications》 2024年第4期14-30,共17页
Multi-view Subspace Clustering (MVSC) emerges as an advanced clustering method, designed to integrate diverse views to uncover a common subspace, enhancing the accuracy and robustness of clustering results. The signif... Multi-view Subspace Clustering (MVSC) emerges as an advanced clustering method, designed to integrate diverse views to uncover a common subspace, enhancing the accuracy and robustness of clustering results. The significance of low-rank prior in MVSC is emphasized, highlighting its role in capturing the global data structure across views for improved performance. However, it faces challenges with outlier sensitivity due to its reliance on the Frobenius norm for error measurement. Addressing this, our paper proposes a Low-Rank Multi-view Subspace Clustering Based on Sparse Regularization (LMVSC- Sparse) approach. Sparse regularization helps in selecting the most relevant features or views for clustering while ignoring irrelevant or noisy ones. This leads to a more efficient and effective representation of the data, improving the clustering accuracy and robustness, especially in the presence of outliers or noisy data. By incorporating sparse regularization, LMVSC-Sparse can effectively handle outlier sensitivity, which is a common challenge in traditional MVSC methods relying solely on low-rank priors. Then Alternating Direction Method of Multipliers (ADMM) algorithm is employed to solve the proposed optimization problems. Our comprehensive experiments demonstrate the efficiency and effectiveness of LMVSC-Sparse, offering a robust alternative to traditional MVSC methods. 展开更多
关键词 CLUSTERING Multi-view Subspace Clustering Low-Rank Prior Sparse Regularization
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跨学科视野下对Point of View的重新界定 被引量:8
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作者 申丹 《上海交通大学学报(哲学社会科学版)》 CSSCI 北大核心 2023年第1期1-13,共13页
在西方叙事作品研究界,“point of view”自20世纪初以来一直是一个核心概念和热门话题。叙事学和文体学都十分关注这一话题。表面上看,两个学派对“point of view”进行了大致相同的探讨,而实际上两者在理念和路径上各行其道且相互排... 在西方叙事作品研究界,“point of view”自20世纪初以来一直是一个核心概念和热门话题。叙事学和文体学都十分关注这一话题。表面上看,两个学派对“point of view”进行了大致相同的探讨,而实际上两者在理念和路径上各行其道且相互排斥。叙事学界在探讨“point of view”时,将其囿于观察者的感知(区分“谁说”和“谁感知”),这种自我限制不合情理。与此相对照,文体学在探讨“point of view”时,聚焦于叙述者(说话者)的立场态度,这种自我限制也造成了很大问题。这两个学派在探讨“point of view”时各自的片面性以及相互之间的排他性还导致了不少理论上的混乱。这也对国内的研究造成了影响。本文在指出以往问题的基础上,对“point of view”提出切合实际的新的界定,旨在通过这一新的界定帮助推进理论探讨的发展并促进跨学科研究,以便对叙事作品进行更好、更为全面的分析。 展开更多
关键词 point of view 重新界定 叙事学与文体学 片面与混乱 跨学科研究
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Knowledge-Based Classification in Automated Soil Mapping 被引量:10
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作者 ZHOU BIN and WANG RENCHAOInstitute of Agricultural Remote Sensing and Information Technology Application, Zhejiang University, Hangzhou 310029 (China) 《Pedosphere》 SCIE CAS CSCD 2003年第3期209-218,共10页
A machine-learning approach was developed for automated building of knowledgebases for soil resources mapping by using a classification tree to generate knowledge from trainingdata. With this method, building a knowle... A machine-learning approach was developed for automated building of knowledgebases for soil resources mapping by using a classification tree to generate knowledge from trainingdata. With this method, building a knowledge base for automated soil mapping was easier than usingthe conventional knowledge acquisition approach. The knowledge base built by classification tree wasused by the knowledge classifier to perform the soil type classification of Longyou County,Zhejiang Province, China using Landsat TM bi-temporal images and CIS data. To evaluate theperformance of the resultant knowledge bases, the classification results were compared to existingsoil map based on a field survey. The accuracy assessment and analysis of the resultant soil mapssuggested that the knowledge bases built by the machine-learning method was of good quality formapping distribution model of soil classes over the study area. 展开更多
关键词 CLASSIFICATION classification tree knowledge-based rule extracting soilmapping
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Knowledge-based bridge detection from SAR images 被引量:5
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作者 Wang Wenguang Sun Jinping Hu Rui Mao Shiyi 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2009年第5期929-936,共8页
Automatic bridge detection is an important application of SAR images. Differed from the classical CFAR method, a new knowledge-based bridge detection approach is proposed. The method not only uses the backscattering i... Automatic bridge detection is an important application of SAR images. Differed from the classical CFAR method, a new knowledge-based bridge detection approach is proposed. The method not only uses the backscattering intensity difference between targets and background but also applies the contextual information and spatial relationship between objects. According to bridges' special characteristics and scattering properties in SAR images, the new knowledge-based method includes three processes: river segmentation, potential bridge areas detection and bridge discrimination. The application to AIRSAR data shows that the new method is not sensitive to rivers' shape. Moreover, this method can detect bridges successfully when river segmentation is not very exact and is more robust than the radius projection method. 展开更多
关键词 knowledge-based bridge detection SAR contextual information mathematical morphology.
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3D view序列联合压缩感知技术精准诊断踝周韧带损伤 被引量:1
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作者 张汉智 王植 +1 位作者 孟祥虹 孙曼 《中国CT和MRI杂志》 2023年第6期162-164,共3页
目的应用3 Dview序列联合压缩感知(Compressed Sensing,CS)技术观察踝关节扭伤患者韧带损伤情况,探讨3D view序列与常规2D序列相比能否提高诊断效能。方法前瞻性分析2021年2月至2021年11月来我院急诊就诊的踝关节急性扭伤患者共26例(26... 目的应用3 Dview序列联合压缩感知(Compressed Sensing,CS)技术观察踝关节扭伤患者韧带损伤情况,探讨3D view序列与常规2D序列相比能否提高诊断效能。方法前瞻性分析2021年2月至2021年11月来我院急诊就诊的踝关节急性扭伤患者共26例(26个踝关节)。上述受试均行MRI检查,扫描序列包括常规2D及3D view T2联合压缩感知序列。应用Mann-Whitney U检验评价常规序列及3D view序列的扫描时间、跟腱的信噪比及对比噪声比及评估患者在两序列下腓距前韧带、腓跟韧带、三角韧带、分歧韧带的损伤程度比较有无区别。应用Fisher确切概率法比较两序列对腓距前韧带、腓跟韧带、三角韧带、分歧韧带损伤的检出率有无差别。结果共纳入踝关节扭伤患者26例,3D view+CS序列的扫描时间为376.2±0s,略短于常规序列(381.479±7.3s),两者无明显差别(Z=-1.396,P=0.163)。3D view序列跟腱信噪比明显高于2D常规序列(Z=-3.441,P=0.001);对比噪声比明显高于2D常规序列(Z=-6.094,P<0.01);跟腓韧带和分歧韧带的损伤程度明显高于2D常规序列(Z=-2.67,P=0.008;Z=-2.67,P<0.001)。两序列对于距腓前韧带和内侧三角韧带的损伤程度差异无统计学差别(P<0.05)。3D View+CS序列对分歧韧带损伤的检出率明显高于2D常规序列(P<0.001)。3D View+CS序列较2D常规序列对距腓前韧带、跟腓韧带、内侧三角韧带损伤的检出率无明显差别(P>0.05)。结论在3D View+CS序列与常规2D序列扫描时间相当的情况下,3D View+CS序列图像质量较常规2D序列更高,踝周韧带的检出率更高,并更准确地评估韧带损伤程度。 展开更多
关键词 3D view 压缩感知 踝关节 韧带损伤
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New Knowledge-based Genetic Algorithm for Excavator Boom Structural Optimization 被引量:6
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作者 HUA Haiyan LIN Shuwen 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2014年第2期392-401,共10页
Due to the insufficiency of utilizing knowledge to guide the complex optimal searching, existing genetic algorithms fail to effectively solve excavator boom structural optimization problem. To improve the optimization... Due to the insufficiency of utilizing knowledge to guide the complex optimal searching, existing genetic algorithms fail to effectively solve excavator boom structural optimization problem. To improve the optimization efficiency and quality, a new knowledge-based real-coded genetic algorithm is proposed. A dual evolution mechanism combining knowledge evolution with genetic algorithm is established to extract, handle and utilize the shallow and deep implicit constraint knowledge to guide the optimal searching of genetic algorithm circularly. Based on this dual evolution mechanism, knowledge evolution and population evolution can be connected by knowledge influence operators to improve the conflgurability of knowledge and genetic operators. Then, the new knowledge-based selection operator, crossover operator and mutation operator are proposed to integrate the optimal process knowledge and domain culture to guide the excavator boom structural optimization. Eight kinds of testing algorithms, which include different genetic operators, arc taken as examples to solve the structural optimization of a medium-sized excavator boom. By comparing the results of optimization, it is shown that the algorithm including all the new knowledge-based genetic operators can more remarkably improve the evolutionary rate and searching ability than other testing algorithms, which demonstrates the effectiveness of knowledge for guiding optimal searching. The proposed knowledge-based genetic algorithm by combining multi-level knowledge evolution with numerical optimization provides a new effective method for solving the complex engineering optimization problem. 展开更多
关键词 boom structural optimization dual evolution mechanism knowledge-based genetic strategies deep implicit knowledge domain culture
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