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Metacognition Inspired Reflective Chain-of-Thought for Knowledge-Based VQA
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作者 Zhongfan Sun Kan Guo +1 位作者 Yongli Hu Yong Zhang 《Computers, Materials & Continua》 2026年第4期1909-1933,共25页
Knowledge-based VisualQuestion Answering(VQA)requires the integration of visual information with external knowledge reasoning.Existing approaches typically retrieve information from external corpora and rely on pretra... Knowledge-based VisualQuestion Answering(VQA)requires the integration of visual information with external knowledge reasoning.Existing approaches typically retrieve information from external corpora and rely on pretrained language models for reasoning.However,their performance is often hindered by the limited capabilities of retrievers and the constrained size of knowledge bases.Moreover,relying on image captions to bridge the modal gap between visual and language modalities can lead to the omission of critical visual details.To address these limitations,we propose the Reflective Chain-of-Thought(ReCoT)method,a simple yet effective framework inspired by metacognition theory.ReCoT effectively activates the reasoning capabilities ofMultimodal Large LanguageModels(MLLMs),providing essential visual and knowledge cues required to solve complex visual questions.It simulates a metacognitive reasoning process that encompasses monitoring,reflection,and correction.Specifically,in the initial generation stage,an MLLM produces a preliminary answer that serves as the model’s initial cognitive output.During the reflective reasoning stage,this answer is critically examined to generate a reflective rationale that integrates key visual evidence and relevant knowledge.In the final refinement stage,a smaller language model leverages this rationale to revise the initial prediction,resulting in amore accurate final answer.By harnessing the strengths ofMLLMs in visual and knowledge grounding,ReCoT enables smaller language models to reason effectively without dependence on image captions or external knowledge bases.Experimental results demonstrate that ReCoT achieves substantial performance improvements,outperforming state-of-the-art methods by 2.26%on OK-VQA and 5.8%on A-OKVQA. 展开更多
关键词 knowledge-based VQA METACOGNITION reflective chain-of-thought answer refinement
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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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A physics knowledge-based surrogate model framework for timedependent slope deformation:Considering water effect and sliding states
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作者 Wenyu Zhuang Yaoru Liu +3 位作者 Kai Zhang Qingchao Lyu Shaokang Hou Qiang Yang 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第9期5416-5436,共21页
The surrogate model serves as an efficient simulation tool during the slope parameter inversion process.However,the creep constitutive model integrated with dynamic damage evolution poses challenges in development of ... The surrogate model serves as an efficient simulation tool during the slope parameter inversion process.However,the creep constitutive model integrated with dynamic damage evolution poses challenges in development of the required surrogate model.In this study,a novel physics knowledge-based surrogate model framework is proposed.In this framework,a Transformer module is employed to capture straindriven softening-hardening physical mechanisms.Positional encoding and self-attention are utilized to transform the constitutive parameters associated with shear strain,which are not directly time-related,into intermediate latent features for physical loss calculation.Next,a multi-layer stacked GRU(gated recurrent unit)network is built to provide input interfaces for time-dependent intermediate latent features,hydraulic boundary conditions,and water-rock interaction degradation equations,with static parameters introduced via external fully-connected layers.Finally,a combined loss function is constructed to facilitate the collaborative training of physical and data loss,introducing time-dependent weight adjustments to focus the surrogate model on accurate deformation predictions during critical phases.Based on the deformation of a reservoir bank landslide triggered by impoundment and subsequent restabilization,an elasto-viscoplastic constitutive model that considers water effect and sliding state dependencies is developed to validate the proposed surrogate model framework.The results indicate that the framework exhibits good performance in capturing physical mechanisms and predicting creep behavior,reducing errors by about 30 times compared to baseline models such as GRU and LSTM(long short-term memory),meeting the precision requirements for parameter inversion.Ablation experiments also confirmed the effectiveness of the framework.This framework can also serve as a reference for constructing other creep surrogate models that involve non-time-related across dimensions. 展开更多
关键词 Reservoir bank slope Time-dependent deformation Elasto-viscoplastic constitutive model Physics knowledge-based deep learning Surrogate model
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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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A rectangular cross-section field-of-view rotational computed laminography and its analytical reconstruction method
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作者 Xiang Zou Wu-Liang Shi +1 位作者 Mu-Ge Du Yu-Xiang Xing 《Nuclear Science and Techniques》 2026年第3期18-34,共17页
Rotational computed laminography(CL)has broad application potential in three-dimensional imaging of plate-like objects because it only requires X-rays to pass through the tested object in the thickness direction durin... Rotational computed laminography(CL)has broad application potential in three-dimensional imaging of plate-like objects because it only requires X-rays to pass through the tested object in the thickness direction during the imaging process.In this study,a rectangular cross-section field-of-view rotational CL(RC-CL)is proposed for circuit board imaging.Compared to other rotational CL systems,the field of view is the largest and most suitable for rectangular circuit boards.Meanwhile,as the imaging geometry of RC-CL is significantly different from that of cone-beam CT,the Feldkamp-Davis-Kress(FDK)reconstruction algorithm cannot be used directly.However,transferring the projection data to fit into the CBCT geometry using two-dimensional interpolation introduces interpolation errors.Therefore,an FDK-type analytical reconstruction algorithm applicable to RC-CL was developed.The effectiveness of the method was validated through numerical experiments,and the influence of the tilt angle on the reconstruction results was analyzed.Finally,the RC-CL technique was applied to real defect detection research on circuit boards. 展开更多
关键词 Computed tomography(CT) Computed laminography(CL) Field of view FDK Analytical reconstruction
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Calculation of Viewing and Solar Geometry Angles for the Fengyun-4B Geostationary Satellite
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作者 Dazhi YANG Yuhang MA +2 位作者 Yun CAO Lei YANG Hai ZHANG 《Advances in Atmospheric Sciences》 2026年第4期736-743,共8页
The calculation of viewing and solar geometry angles is a critical first step in retrieving atmospheric and surface variables from geostationary satellite observations.Whereas the viewing angles for geostationary sate... The calculation of viewing and solar geometry angles is a critical first step in retrieving atmospheric and surface variables from geostationary satellite observations.Whereas the viewing angles for geostationary satellites are not timevarying,a primary source of inaccuracy in solar positioning is the use of a single timestamp.Since pixel scanning times can differ significantly across the field-of-view disk(e.g.,by approximately 13 min for Fengyun-4B),this practice leads to errors of up to±2°in solar zenith angle,which translates to±50 W m^(−2) in extraterrestrial irradiance;the errors in solar azimuth angle can exceed±100°.Beyond scanning time,this work also quantifies the impact of other inputs—including altitude,surface pressure,air temperature,difference between Terrestrial Time and Universal Time,and atmospheric refraction—on the resulting angles.A comparison of our precise calculations with the official National Satellite Meteorological Center L1_GEO product shows an accuracy within 0.1°,confirming its utility for most retrieval tasks.To facilitate higher precision when required,this work releases the corresponding satellite and solar positioning codes in both R and Python. 展开更多
关键词 Fengyun-4B viewing and solar geometry solar position algorithm geostationary satellite code availability
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The utility of the trans-splenic retrocardiac view in supine critically ill patients
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作者 Issac Cheong Pablo Martín Merlo Francisco Marcelo Tamagnone 《World Journal of Emergency Medicine》 2026年第2期205-206,共2页
Monitoring cardiac function is a fundamental component of the diagnosis and management of critically ill patients.While pulmonary artery catheterization has long served as the standard for hemodynamic assessment,its i... Monitoring cardiac function is a fundamental component of the diagnosis and management of critically ill patients.While pulmonary artery catheterization has long served as the standard for hemodynamic assessment,its invasive nature and associated risks have shifted clinical practice toward non-invasive modalities.^([1]) Among these methods,point-of-care ultrasound(POCUS) has gained widespread acceptance,offering real-time bedside evaluation of cardiac function. 展开更多
关键词 cardiac function monitoring monitoring cardiac function hemodynamic assessmentits trans splenic retrocardiac view non invasive modalities cardiac function pulmonary artery catheterization supine critically ill patients
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现代检测技术与LabVIEW实验课程交叉融合的探索与改革
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作者 宋爱娟 张国荣 +1 位作者 袁重焕 孟范伟 《实验室科学》 2025年第1期67-72,77,共7页
随着科技进步以及学生求职需求,高校教学中学科的交叉与综合运用已经成为高等教育深化改革和发展的必然趋势。因此,基于东北大学自动化、测控技术与仪器等领域改革的成功经验,在实验教学探索过程中,将现代检测技术中的传感器检测与转换... 随着科技进步以及学生求职需求,高校教学中学科的交叉与综合运用已经成为高等教育深化改革和发展的必然趋势。因此,基于东北大学自动化、测控技术与仪器等领域改革的成功经验,在实验教学探索过程中,将现代检测技术中的传感器检测与转换实验同功能强大的虚拟仪器Lab VIEW软件实验课程相结合,搭建基于虚拟仪器技术的传感器综合实验平台,将平台的物理设备、计算机通信、软件设计和人机交互界面的建立与设计统筹为实验课程的全部内容。采用这个平台可以模拟科研及项目开发的完整过程,从而培养学生开发项目的实践能力、科研能力、创造能力,同时提高实验室设备的利用效率,使教育教学资源得到充分利用,改变了当下传统验证实验现象、与工程实践严重脱节的实验课程。 展开更多
关键词 传感器技术 Lab view 学科的交叉融合 实验课程改革
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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 +1 位作者 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 inte... 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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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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Structural Topology Design of Container Ship Based on Knowledge-Based Engineering and Level Set Method 被引量:5
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作者 崔进举 王德禹 史琪琪 《China Ocean Engineering》 SCIE EI CSCD 2015年第4期551-564,共14页
Knowledge-Based Engineering (KBE) is introduced into the ship structural design in this paper. From the implementation of KBE, the design solutions for both Rules Design Method (RDM) and Interpolation Design Meth... Knowledge-Based Engineering (KBE) is introduced into the ship structural design in this paper. From the implementation of KBE, the design solutions for both Rules Design Method (RDM) and Interpolation Design Method (IDM) are generated. The corresponding Finite Element (FE) models are generated. Topological design of the longitudinal structures is studied where the Gaussian Process (GP) is employed to build the surrogate model for FE analysis. Multi-objective optimization methods inspired by Pareto Front are used to reduce the design tank weight and outer surface area simultaneously. Additionally, an enhanced Level Set Method (LSM) which employs implicit algorithm is applied to the topological design of typical bracket plate which is used extensively in ship structures. Two different sets of boundary conditions are considered. The proposed methods show satisfactory efficiency and accuracy. 展开更多
关键词 knowledge-based Engineering (KBE) Level Set Method (LSM) Gaussian Process GP)
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FAULT DIAGNOSIS OF ROTATING MACHINERY USING KNOWLEDGE-BASED FUZZY NEURAL NETWORK 被引量:2
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作者 李如强 陈进 伍星 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2006年第1期99-108,共10页
A novel knowledge-based fuzzy neural network (KBFNN) for fault diagnosis is presented. Crude rules were extracted and the corresponding dependent factors and antecedent coverage factors were calculated firstly from ... A novel knowledge-based fuzzy neural network (KBFNN) for fault diagnosis is presented. Crude rules were extracted and the corresponding dependent factors and antecedent coverage factors were calculated firstly from the diagnostic sample based on rough sets theory. Then the number of rules was used to construct partially the structure of a fuzzy neural network and those factors were implemented as initial weights, with fuzzy output parameters being optimized by genetic algorithm. Such fuzzy neural network was called KBFNN. This KBFNN was utilized to identify typical faults of rotating machinery. Diagnostic results show that it has those merits of shorter training time and higher right diagnostic level compared to general fuzzy neural networks. 展开更多
关键词 rotating machinery fault diagnosis rough sets theory fuzzy sets theory generic algorithm knowledge-based fuzzy neural network
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A Knowledge-based System for the Analysis of the Ability of Paying back Loans 被引量:1
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作者 Zhu Ming(朱明) +1 位作者 Yang Baoan(杨保安) 《Journal of Donghua University(English Edition)》 EI CAS 2001年第1期123-126,共4页
This paper describes the development of a knowledgebased system (KBS) for determining whether or not, and under what conditions, a bank Ioan officer should grant a business loan to a company. The prototype system deve... This paper describes the development of a knowledgebased system (KBS) for determining whether or not, and under what conditions, a bank Ioan officer should grant a business loan to a company. The prototype system developed focuses on what is bank loans risks management, how to prevent risk by the analysis of the ability of paying back loans. The paper makes the structural analysis involved in the system's decision situation, the structured situation diagram or model, dependency diagram and the document needed by the KBS prototype system thus are developed. Through testing the samples from loan business, the quality for the analysis of the ability of paying back loans can be effectively evaluated by the KBS prototype system. 展开更多
关键词 knowledge-based SYSTEM (KBS) the KBS prototype system the ABILITY of paying BACK loans bank LOANS risk management.
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Integration of Decision-Support and Knowledge-Based Techniques in a Problem-Solving Strategy for Selection Problems 被引量:1
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作者 David McSherry(School of Information and Software Engineering,Faculty of Informatics, University of Ulster,Coleraine BT52 1SA, Northern Ireland) 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1996年第2期35-54,共20页
The limitations of traditional approaches to selection problems are examined. A problemsolving strategy is presented in which decision-support and knowledge-based techniques play complementary roles. An approach to th... The limitations of traditional approaches to selection problems are examined. A problemsolving strategy is presented in which decision-support and knowledge-based techniques play complementary roles. An approach to the representation of knowledge to support the problem-solving strategy is presented which avoids commitment to a specific programming language or implementation environment. The problem of choosing a home is used to illustrate the representation of knowledge in a specific problem domain. Techniques for implementation of the problem-solving strategy are described. Knowledge elicitation techniques and their implementation in a development shell for application of the problem-solving strategy to any selection problem are also described. 展开更多
关键词 knowledge-based systems Decision-support systems Knowledge acquisition Multiple criteria decision making Operational research Analytic hierarchy process
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Yarn Quality Prediction and Diagnosis Based on Rough Set and Knowledge-Based Artificial Neural Network 被引量:1
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作者 杨建国 徐兰 +1 位作者 项前 刘彬 《Journal of Donghua University(English Edition)》 EI CAS 2014年第6期817-823,共7页
In the spinning process, some key process parameters( i. e.,raw material index inputs) have very strong relationship with the quality of finished products. The abnormal changes of these process parameters could result... In the spinning process, some key process parameters( i. e.,raw material index inputs) have very strong relationship with the quality of finished products. The abnormal changes of these process parameters could result in various categories of faulty products. In this paper, a hybrid learning-based model was developed for on-line intelligent monitoring and diagnosis of the spinning process. In the proposed model, a knowledge-based artificial neural network( KBANN) was developed for monitoring the spinning process and recognizing faulty quality categories of yarn. In addition,a rough set( RS)-based rule extraction approach named RSRule was developed to discover the causal relationship between textile parameters and yarn quality. These extracted rules were applied in diagnosis of the spinning process, provided guidelines on improving yarn quality,and were used to construct KBANN. Experiments show that the proposed model significantly improve the learning efficiency, and its prediction precision is improved by about 5. 4% compared with the BP neural network model. 展开更多
关键词 yarn quality prediction rough set(RS) knowledge discovery knowledge-based artificial neural network(KBANN)
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一位晚清来华西方人眼中的“中国形象”——以《中国一览》(A View of China)为例
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作者 卞浩宇 《语言与文化研究》 2025年第5期221-224,共4页
1817年一本名为《中国一览》的英文书籍在澳门地区出版发行。该书作者系新教首位来华传教士马礼逊。在书中,马礼逊从来华西方人的视角对中国的历史、地理、政治、风俗等多方面做了较为详细的介绍和说明,向西方读者描绘了他眼中的“中国... 1817年一本名为《中国一览》的英文书籍在澳门地区出版发行。该书作者系新教首位来华传教士马礼逊。在书中,马礼逊从来华西方人的视角对中国的历史、地理、政治、风俗等多方面做了较为详细的介绍和说明,向西方读者描绘了他眼中的“中国形象”。《中国一览》的出版,不仅在推动当时西方人汉语学习以及海外汉学发展方面起到了积极作用,而且书中“他者”的叙述视角所反映出的西方对中国文化的整体态度乃至误解都可以为当前“中国文化走出去”战略提供有益的历史经验和借鉴。 展开更多
关键词 马礼逊 《中国一览》 中国形象 影响 借鉴
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MY PERSONAL STUDY ON KNOWLEDGE-BASED ECONOMY 被引量:2
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作者 Deng Shuhui(Institute of Systems Science, the CAS) 《Bulletin of the Chinese Academy of Sciences》 1999年第2期119-120,共2页
The Financial Crisis in Asia is having a negative impacion the economic development of China, but it also enlightens us. It makes us consider and take measures to avoid such a crisis. I have put forward six measures, ... The Financial Crisis in Asia is having a negative impacion the economic development of China, but it also enlightens us. It makes us consider and take measures to avoid such a crisis. I have put forward six measures, one of which is to promote the transformation of S&T knowledge into productive forces. 展开更多
关键词 MODE MY PERSONAL STUDY ON knowledge-based ECONOMY
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Research on Knowledge-based Connecting Elements Modeling
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作者 HUANG Xiang, YAN Chong-jing (College of Mechanical and Electrical Engineering, Nanjing University o f Aeronautics and Astronautics, Nanjing 210016, China) 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第S1期162-163,共2页
Steps of manipulation is required to complete the m od eling of the connection elements such as bolt, pin and the like in commerce CAD system. It leads to low efficiency, difficulty to assure the relative position, im... Steps of manipulation is required to complete the m od eling of the connection elements such as bolt, pin and the like in commerce CAD system. It leads to low efficiency, difficulty to assure the relative position, impossibility to express rules and knowledge. Based on the inner character analy sis of interpart, detail modification and assembly relation of mechanical connec ting element, the idea, which extends the feature modeling of part to the interp art feature modeling for assembly purpose, is presented, and virtual part based connecting element modeling is proposed. Virtual part is a complement set of lo cal modification of part to be connected. In assembly modeling, base part is mod ified by Boolean operation between base part and virtual part. The modeling and assembly is finished just in one operation, at the same time the rules and knowl edge of the connection elements are encapsulated through virtual part. According to this mechanism, a knowledge-based connecting elements rapid design module i s developed on commerce software package UG with satisfying results. 展开更多
关键词 CAD knowledge-based engineering ASSEMBLY conn ecting element
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Optimizing the atom types of proteins through iterative knowledge-based potentials
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作者 汪心享 黄胜友 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第2期43-50,共8页
Knowledge-based scoring functions have been widely used for protein structure prediction, protein-small molecule, and protein-nucleic acid interactions, in which one critical step is to find an appropriate representat... Knowledge-based scoring functions have been widely used for protein structure prediction, protein-small molecule, and protein-nucleic acid interactions, in which one critical step is to find an appropriate representation of protein structures. A key issue is to determine the minimal protein representations, which is important not only for developing of scoring func- tions but also for understanding the physics of protein folding. Despite significant progresses in simplifying residues into alphabets, few studies have been done to address the optimal number of atom types for proteins. Here, we have investigated the atom typing issue by classifying the 167 heavy atoms of proteins through 11 schemes with 1 to 20 atom types based on their physicochemical and functional environments. For each atom typing scheme, a statistical mechanics-based iterative method was used to extract atomic distance-dependent potentials from protein structures. The atomic distance-dependent pair potentials for different schemes were illustrated by several typical atom pairs with different physicochemical proper- ties. The derived potentials were also evaluated on a high-resolution test set of 148 diverse proteins for native structure recognition. It was found that there was a crossover around the scheme of four atom types in terms of the success rate as a function of the number of atom types, which means that four atom types may be used when investigating the basic folding mechanism of proteins. However, it was revealed by a close examination of typical potentials that 14 atom types were needed to describe the protein interactions at atomic level. The present study will be beneficial for the development of protein related scoring functions and the understanding of folding mechanisms. 展开更多
关键词 atom types knowledge-based potentials statistical mechanics ITERATION
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