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A Rapid Method for Matching Pair Determination from Disordered and Massive Asteroid Im
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作者 ZHANG Jiujiang GENG Xun +4 位作者 YU Junming LIU Jie LIU Pengying PENG Zhen MA Xin 《深空探测学报(中英文)》 北大核心 2025年第5期542-556,共15页
This paper proposed an efficient method of image overlapping relationship analysis based on spatial index of KD tree fast search for disordered and large-scale asteroid images.In this study,the image data from asteroi... This paper proposed an efficient method of image overlapping relationship analysis based on spatial index of KD tree fast search for disordered and large-scale asteroid images.In this study,the image data from asteroid exploration missions such as Bennu,Vesta,and Ryugu were used for experiments,and the proposed image matching pairs determination algorithm was comprehensively compared with the corresponding modules of USGS ISIS in order to evaluate its performance in terms of efficiency and accuracy.The results show that when processing more than a thousand images,the proposed method greatly improves the efficiency of acquiring image matching pairs while ensuring the correctness of image overlapping relationships and accuracy of bundle adjustment.At the same time,according to the obtained image matching pairs,images that meet the requirements of Stereo Photoclinometry can be quickly selected,effectively improving the quality of 3D reconstruction models of asteroid images. 展开更多
关键词 asteroid exploration PHOTOGRAMMETRY image matching KD tree image matching pairs
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Precision Comparison and Analysis of Multi-stereo Fusion and Multi-view Matching Based on High-Resolution Satellite Data
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作者 LIU Tengfei HUANG Xu HUANG Zefeng 《Transactions of Nanjing University of Aeronautics and Astronautics》 2025年第5期577-588,共12页
High-resolution sub-meter satellite data play an increasingly crucial role in the 3D real-scene China construction initiative.Current research on 3D reconstruction using high-resolution satellite data primarily focuse... High-resolution sub-meter satellite data play an increasingly crucial role in the 3D real-scene China construction initiative.Current research on 3D reconstruction using high-resolution satellite data primarily focuses on two approaches:Multi-stereo fusion and multi-view matching.While algorithms based on these two methodologies for multi-view image 3D reconstruction have reached relative maturity,no systematic comparison has been conducted specifically on satellite data to evaluate the relative merits of multi-stereo fusion versus multi-view matching methods.This paper conducts a comparative analysis of the practical accuracy of both approaches using high-resolution satellite datasets from diverse geographical regions.To ensure fairness in accuracy comparison,both methodologies employ non-local dense matching for cost optimization.Results demonstrate that the multi-stereo fusion method outperforms multi-view matching in all evaluation metrics,exhibiting approximately 1.2%higher average matching accuracy and 10.7%superior elevation precision in the experimental datasets.Therefore,for 3D modeling applications using satellite data,we recommend adopting the multi-stereo fusion approach for digital surface model(DSM)product generation. 展开更多
关键词 multi-stereo fusion reconstruction multi-view matching reconstruction non-local dense matching method occlusion detection high-resolution satellite data
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More efficient ontology matching algorithm for integrating heterogeneous web resources 被引量:1
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作者 刘晨 韩燕波 +1 位作者 陈旺虎 丁维龙 《Journal of Southeast University(English Edition)》 EI CAS 2007年第3期381-384,共4页
To improve the performance of the ontology matching process, a more efficient ontology matching algorithm, which can effectively eliminate unnecessary operations of matching entities, is proposed. By the theoretical a... To improve the performance of the ontology matching process, a more efficient ontology matching algorithm, which can effectively eliminate unnecessary operations of matching entities, is proposed. By the theoretical analysis and proof, a set of matching rules are summarized for depicting inherent relations among matching results of entities. Based on these rules, the proposed algorithm can reuse the matching results of two entities to directly determine the matching results of their adjacent entities. Thereby, redundant operations of matching adjacent entities can be avoided, which can improve the performance of the whole matching process. The experimental results show that, compared with related algorithms, the proposed algorithm has high matching accuracy and can remarkably reduce the consuming time of the whole matching process. So, the proposed algorithm is more competent for the large-scale ontology matching which often occurs in the practical heterogeneous web resources integration project. 展开更多
关键词 ontology matching matching performance matching rule
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A Novel Method for Multi-image Matching Synthesizing Image and Object-space Information 被引量:1
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作者 袁修孝 明洋 《Geo-Spatial Information Science》 2009年第3期157-164,共8页
A novel method for multi-image matching by synthesizing image and object-space information is proposed. Firstly, four levels of image pyramids are generated according to the rule that the next pyramid level is generat... A novel method for multi-image matching by synthesizing image and object-space information is proposed. Firstly, four levels of image pyramids are generated according to the rule that the next pyramid level is generated from the previous level using the average gray values of the 3 by 3 pixels, and the first level of pyramid image is generated from the original image. The initial horizontal parallaxes between the reference image and each searching image are calculated at the highest level of the image pyramid. Secondly, corresponding image points are searched in each stereo image pair from the third level of image pyramid, and the matching results in all stereo pairs are integrated in the object space, by which the mismatched image points can be eliminated and more accurate spatial information can be obtained for the subsequent pyramid image matching. The matching method based on correlation coefficient with geometric constraints and global relaxation matching is introduced in the process of image matching. Finally, the feasibility of the method proposed in this paper is verified by the experiments using a set of digital frame aerial images with big overlap. Compared with the traditional image matching method with two images, the accuracy of the digital surface model (DSM) generated using the proposed method shows that the multiimage matching method can eliminate the mismatched points effectively and can improve the matching success rate significantly. 展开更多
关键词 multi-image matching digital surface model (DSM) cross correlation matching with geometric constraints relaxation matching matching success rate
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Micro-ridge-furrow planting increases rapeseed yield and resource utilization efficiency through optimizing field microenvironment and light-nitrogen matching 被引量:1
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作者 Xianling Wang Lin Li +15 位作者 Chunyun Wang Zongkai Wang Mengliang Li Xiaoqiang Tan Lei Zhang Tianyao Wang Yuanwei Zhou Xiongze Xie Sen Qiu Yitao Liao Jie Kuai Bo Wang Jing Wang Zhenghua Xu Jie Zhao Guangsheng Zhou 《The Crop Journal》 2025年第2期587-596,共10页
The effects of micro-ridge-furrow planting(MR)on yield and the efficiency of light,water,and thermal resource use in rapeseed were tested in a three-year field experiment comparing MR to conventional flat planting.MR ... The effects of micro-ridge-furrow planting(MR)on yield and the efficiency of light,water,and thermal resource use in rapeseed were tested in a three-year field experiment comparing MR to conventional flat planting.MR enhanced canopy heterogeneity by altering the leaf angle between plants on ridges and furrows.The heterogeneous canopy environment increased intercepted photosynthetic active radiation,alleviated canopy temperature stress,and optimized canopy humidity,leading to improvements in light-nitrogen matching and net photosynthetic rate.Consequently,dry matter and yield increased by 13.0%and 11.0%,respectively,while radiation,thermal,and precipitation utilization efficiency increased by 12.3%-16.2%.The corresponding improvements in yield and resource use efficiency were attributed to a heterogeneous canopy environment that improved microclimatic conditions. 展开更多
关键词 Direct-seeded rapeseed Micro-ridge-furrow Canopy heterogeneity Resources utilization efficiency Light-nitrogen matching
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Optimal Production Capacity Matching for Blockchain-Enabled Manufacturing Collaboration With the Iterative Double Auction Method 被引量:1
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作者 Ying Chen Feilong Lin +2 位作者 Zhongyu Chen Changbing Tang Cailian Chen 《IEEE/CAA Journal of Automatica Sinica》 2025年第3期550-562,共13页
The increased demand for personalized customization calls for new production modes to enhance collaborations among a wide range of manufacturing practitioners who unnecessarily trust each other.In this article,a block... The increased demand for personalized customization calls for new production modes to enhance collaborations among a wide range of manufacturing practitioners who unnecessarily trust each other.In this article,a blockchain-enabled manufacturing collaboration framework is proposed,with a focus on the production capacity matching problem for blockchainbased peer-to-peer(P2P)collaboration.First,a digital model of production capacity description is built for trustworthy and transparent sharing over the blockchain.Second,an optimization problem is formulated for P2P production capacity matching with objectives to maximize both social welfare and individual benefits of all participants.Third,a feasible solution based on an iterative double auction mechanism is designed to determine the optimal price and quantity for production capacity matching with a lack of personal information.It facilitates automation of the matching process while protecting users'privacy via blockchainbased smart contracts.Finally,simulation results from the Hyperledger Fabric-based prototype show that the proposed approach increases social welfare by 1.4%compared to the Bayesian game-based approach,makes all participants profitable,and achieves 90%fairness of enterprises. 展开更多
关键词 Blockchain iterative double auction manufacturing collaboration production capacity matching
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Capacity matching and optimization of solarground source heat pump coupling systems 被引量:1
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作者 Jing-hui Luo Yun-xin Huang +4 位作者 Jing-gang Wang Wei Liu Wen-hong Wang Zi-chen Han Chang-jian Zhang 《Applied Geophysics》 2025年第3期739-750,895,共13页
Ground source heat pump systems demonstrate significant potential for northern rural heating applications;however,the effectiveness of these systems is often limited by challenging geological conditions.For instance,i... Ground source heat pump systems demonstrate significant potential for northern rural heating applications;however,the effectiveness of these systems is often limited by challenging geological conditions.For instance,in certain regions,the installation of buried pipes for heat exchangers may be complicated,and these pipes may not always serve as efficient low-temperature heat sources for the heat pumps of the system.To address this issue,the current study explored the use of solar-energy-collecting equipment to supplement buried pipes.In this design,both solar energy and geothermal energy provide low-temperature heat to the heat pump.First,a simulation model of a solar‒ground source heat pump coupling system was established using TRNSYS.The accuracy of this model was validated through experiments and simulations on various system configurations,including varying numbers of buried pipes,different areas of solar collectors,and varying volumes of water tanks.The simulations examined the coupling characteristics of these components and their influence on system performance.The results revealed that the operating parameters of the system remained consistent across the following configurations:three buried pipes,burial depth of 20 m,collector area of 6 m^(2),and water tank volume of 0.5 m^(3);four buried pipes,burial depth of 20 m,collector area of 3 m^(2),and water tank volume of 0.5 m^(3);and five buried pipes with a burial depth of 20 m.Furthermore,the heat collection capacity of the solar collectors spanning an area of 3 m^(2)was found to be equivalent to that of one buried pipe.Moreover,the findings revealed that the solar‒ground source heat pump coupling system demonstrated a lower annual cumulative energy consumption compared to the ground source heat pump system,presenting a reduction of 5.31%compared to the energy consumption of the latter. 展开更多
关键词 solar‒ground source heat pump coupling system OPTIMIZATION TRNSYS energy-saving operation matching design
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The Ordering of Unicyclic Graphs with Minimal Matching Energies
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作者 DONG Bo LI Huan WANG Ligong 《数学进展》 北大核心 2025年第5期951-972,共22页
The concept of matching energy was proposed by Gutman and Wagner firstly in 2012. Let G be a simple graph of order n and λ1, λ2, . . . , λn be the zeros of its matching polynomial. The matching energy of a graph G ... The concept of matching energy was proposed by Gutman and Wagner firstly in 2012. Let G be a simple graph of order n and λ1, λ2, . . . , λn be the zeros of its matching polynomial. The matching energy of a graph G is defined as ME(G) = Pni=1 |λi|. By the famous Coulson’s formula, matching energies can also be calculated by an improper integral depending on a parameter. A k-claw attaching graph Gu(k) refers to the graph obtained by attaching k pendent edges to the graph G at the vertex u, where u is called the root of Gu(k). In this paper, we use some theories of mathematical analysis to obtain a new technique to compare the matching energies of two k-claw attaching graphs Gu(k) and Hv(k) with the same order, that is, limk→∞[ME(Gu(k)) − ME(Hv(k))] = ME(G − u) − ME(H − v). By the technique, we finally determine unicyclic graphs of order n with the 9th to 13th minimal matching energies for all n ≥ 58. 展开更多
关键词 matching energy unicyclic graph quasi-order relation k-claw attaching graph
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Dominating Induced Matching of Generalized Petersen Graphs
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作者 CHEN Ming ZANG Weiqi ZHOU Shan 《数学进展》 北大核心 2025年第6期1223-1232,共10页
A dominating induced matching(DIM)of G is an induced matching that dominates every edge of G.In this note,we completely determine the number of DIMs in the generalized Petersen graph P(n,k).We prove that if P(n,k)is a... A dominating induced matching(DIM)of G is an induced matching that dominates every edge of G.In this note,we completely determine the number of DIMs in the generalized Petersen graph P(n,k).We prove that if P(n,k)is a generalized Petersen graph with n=0(mod 5)and k=2,3(mod 5),then E(P(n,k))can be partitioned into five DIMs.Meanwhile,in the left cases k=0,1,4(mod 5),we build some counterexamples to show that there exist some P(n,k)'s which are DIM-free. 展开更多
关键词 dominating induced matching generalized Petersen graph
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HashTrie Functional Framework and Its Application in Chinese-English Pattern Matching
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作者 ZUO Zhengkang ZHOU Chao +1 位作者 ZENG Zhicheng WANG Changjing 《Wuhan University Journal of Natural Sciences》 2025年第2期184-194,共11页
Most existing multi-pattern matching algorithms are designed for single English texts leading to issues such as missed matches and space expansion when applied to Chinese-English mixed-text environments.The Hash Trie-... Most existing multi-pattern matching algorithms are designed for single English texts leading to issues such as missed matches and space expansion when applied to Chinese-English mixed-text environments.The Hash Trie-based matching machine demonstrates strong compatibility with both Chinese and English,ensuring high accuracy in text processing and subtree positioning.In this study,a novel functional framework based on the HashTrie structure is proposed and mechanically verified using Isabelle/HOL.This framework is applied to design Functional Multi-Pattern Matching(FMPM),the first functional multi-pattern matching algorithm for Chinese-English mixed texts.FMPM constructs the HashTrie matching machine using character codes and threads the machine according to the associations between pattern strings.The experimental results show that as the stored string information increases,the proposed algorithm demonstrates more significant optimization in retrieval efficiency.FMPM simplifies the implementation of the Threaded Hash Trie(THT)for Chinese-English mixed texts,effectively reducing the uncertainties in the transition from the algorithm description to code implementation.FMPM addresses the problem of space explosion Chinese-English mixed texts and avoids issues such as bound variable iteration errors.The functional framework of the HashTrie structure serves as a reference for the formal verification of future HashTrie-based algorithms. 展开更多
关键词 multi-pattern matching Chinese-English mixed HashTrie FUNCTIONAL mechanized verification
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A NURBS-based, perfectly matched layer method for transient elastodynamics in unbounded domains
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作者 Arturo Méndez Salas Myung-Jin Choi Sven Klinkel 《Earthquake Engineering and Engineering Vibration》 2025年第3期723-742,共20页
In this study,the wave motion in elastodynamics for unbounded media is modeled using an unsplit-field perfectly matched layer(PML)formulation that is solved by employing an isogeometric analysis(IGA).In the adopted co... In this study,the wave motion in elastodynamics for unbounded media is modeled using an unsplit-field perfectly matched layer(PML)formulation that is solved by employing an isogeometric analysis(IGA).In the adopted combination,the non-uniform rational B-spline(NURBS)functions are employed as basis functions.Moreover,the unbounded and artificial domains,defined in the PML method,are contained in a single patch domain.Based on the proposed scheme,the approximation of the geometry problem is set in a new scheme in which the PML’s absorbing and attenuation properties and the description of traveling waves can be represented.This includes a higher continuity and smoother approximation of the computed domain.As high-order NURBS basis functions are non-interpolatory,a penalty method is present to apply a time-dependent displacement load.The performance of the NURBS-based PML is analyzed through numerical examples for 1D and 2D domains,considering homogeneous and heterogeneous media.Further,we verify the long-time numerical stability of the present method.The developed method can be used to simulate hypothetical stratified domains commonly encountered in soil-structure interaction analyses. 展开更多
关键词 perfectly matched layer NURBS ELASTODYNAMICS unbounded domains transient analysis
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Study on the Influence of Psychological Factors on Badminton Matches of Capital Universities
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作者 Xuan Zhou 《Journal of Contemporary Educational Research》 2025年第7期312-316,共5页
This study systematically analyzes the influence mechanism of psychological factors on the competition performance of badminton athletes in capital universities through the recent actual participation of university te... This study systematically analyzes the influence mechanism of psychological factors on the competition performance of badminton athletes in capital universities through the recent actual participation of university teams in college badminton matches and combined with high-quality literature.The study finds that anxiety,self-efficacy,and factors from audiences and referees are the main influencing variables,and significant gender differences exist.Based on the empirical research results,a psychological intervention program combining mindfulness training,virtual reality technology,and biofeedback training is proposed to provide a scientific basis for psychological training of college badminton athletes. 展开更多
关键词 Badminton match Psychological factors College athletes Psychological training
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High-altitude effect on corneal endothelial cells and prognosis in patients with cataract surgeries:a propensity score matched analysis
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作者 Li-Li Zhu Bing-Xue Zhu +6 位作者 Yue Han Yong-Yan Tang Ying-Ying Wen Xu-Hong Zhang Li-Yue Zhang Ri-Lei Zhu Dong-Yu Guo 《International Journal of Ophthalmology(English edition)》 2025年第3期409-414,共6页
AIM:To compare analysis of the impact of high altitude on corneal endothelial cells,and the prognosis in patients with cataract surgeries.METHODS:Totally 265 plateau patients with cataract surgeries performed between ... AIM:To compare analysis of the impact of high altitude on corneal endothelial cells,and the prognosis in patients with cataract surgeries.METHODS:Totally 265 plateau patients with cataract surgeries performed between January 2019 and July 2022(average altitude=3000 m),and 524 plain patients with cataract surgeries performed between January 2020 and July 2022 were included.The propensity score matching(PSM)method was applied to match the basic information of patients in both regions on a 1:1 basis.Corneal endothelial cell density(ECD),coefficient of variation(CV),hexagonal cell ratio(HEX),duration of surgery,and pre-and postoperative visual acuity(VA)were compared retrospectively,and correlation tests were done.RESULTS:Totally 223 pairs have been matched successfully.The HEX in the plateau group was higher than that in the plain group(61.95%±6.191%vs 44.91%±6.829%,P<0.001).For ECD and CV,no significant differences were observed between both groups(P>0.1).The pre-and postoperative VA of patients with cataract surgeries in the plateau group were lower(1.40±0.610 vs 0.71±0.514,P<0.001&0.68±0.479 vs 0.18±0.259,P<0.001),and the duration of surgery was longer than those in the plain group(27.06±14.900 min vs 16.03±8.033 min,P<0.001).No significant associations were found between the post-operative VA and the corneal endothelial parameters(P>0.05),while the post-operative VA was significantly related to the pre-operative VA and the duration of surgery(P<0.05).CONCLUSION:The relative hypoxic environment of the plateau does not promote the apoptosis of corneal endothelial cells,but may lead to the compensatory increase of their functions.In plateau patients,no significant associations are found between the poor VA and the corneal endothelial functions early after cataract surgeries. 展开更多
关键词 cataract surgery corneal endothelial cells HYPOXIA PLATEAU propensity score matching
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Visible-Infrared Person Re-Identification via Quadratic Graph Matching and Block Reasoning
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作者 Junfeng Lin Jialin Ma +3 位作者 Wei Chen Hao Wang Weiguo Ding Mingyao Tang 《Computers, Materials & Continua》 2025年第7期1013-1029,共17页
The cross-modal person re-identification task aims to match visible and infrared images of the same individual.The main challenges in this field arise from significant modality differences between individuals and the ... The cross-modal person re-identification task aims to match visible and infrared images of the same individual.The main challenges in this field arise from significant modality differences between individuals and the lack of high-quality cross-modal correspondence methods.Existing approaches often attempt to establish modality correspondence by extracting shared features across different modalities.However,these methods tend to focus on local information extraction and fail to fully leverage the global identity information in the cross-modal features,resulting in limited correspondence accuracy and suboptimal matching performance.To address this issue,we propose a quadratic graph matching method designed to overcome the challenges posed by modality differences through precise cross-modal relationship alignment.This method transforms the cross-modal correspondence problem into a graph matching task and minimizes the matching cost using a center search mechanism.Building on this approach,we further design a block reasoning module to uncover latent relationships between person identities and optimize the modality correspondence results.The block strategy not only improves the efficiency of updating gallery images but also enhances matching accuracy while reducing computational load.Experimental results demonstrate that our proposed method outperforms the state-of-the-art methods on the SYSU-MM01,RegDB,and RGBNT201 datasets,achieving excellent matching accuracy and robustness,thereby validating its effectiveness in cross-modal person re-identification. 展开更多
关键词 Cross-modal person re-identification modal correspondence quadratic graph matching block reasoning
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Knowledge Graph Construction and Rule Matching Approach for Aerospace Product Manufacturability Assessment
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作者 Ziyan Liu Zujie Zheng +1 位作者 Lebao Wu Zuhua Jiang 《Journal of Harbin Institute of Technology(New Series)》 2025年第1期1-14,共14页
After the design of aerospace products is completed,a manufacturability assessment needs to be conducted based on 3D model's features in terms of modeling quality and process design,otherwise the cost of design ch... After the design of aerospace products is completed,a manufacturability assessment needs to be conducted based on 3D model's features in terms of modeling quality and process design,otherwise the cost of design changes will increase.Due to the poor structure and low reusability of product manufacturing feature information and assessment knowledge in the current aerospace product manufacturability assessment process,it is difficult to realize automated manufacturability assessment.To address these issues,a domain ontology model is established for aerospace product manufacturability assessment in this paper.On this basis,a structured representation method of manufacturability assessment knowledge and a knowledge graph data layer construction method are proposed.Based on the semantic information and association information expressed by the knowledge graph,a rule matching method based on subgraph matching is proposed to improve the precision and recall.Finally,applications and experiments based on the software platform verify the effectiveness of the proposed knowledge graph construction and rule matching method. 展开更多
关键词 knowledge graph aerospace product manufacturability assessment rule matching
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Advantages of new generation colonoscopes on adenoma detection:A propensity-score matching study
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作者 Toshihiro Nishizawa Osamu Toyoshima +7 位作者 Shuntaro Yoshida Yoshiyuki Takahashi Hideki Nakagawa Hiroya Mizutani Yosuke Kataoka Takamitsu Kanazawa Hirotoshi Ebinuma Keisuke Hata 《World Journal of Gastrointestinal Endoscopy》 2025年第6期57-63,共7页
BACKGROUND Recently,Olympus Corporation released new scopes(XZ1200/EZ1500).However,there have been few reports on this topic,although improvement in adenoma detection rate(ADR)by texture and color enhancement imaging(... BACKGROUND Recently,Olympus Corporation released new scopes(XZ1200/EZ1500).However,there have been few reports on this topic,although improvement in adenoma detection rate(ADR)by texture and color enhancement imaging(TXI)or computer-aided detection system(CAD)has been reported.AIM To investigate the effects of the scope on the detection of adenomas and sessile serrated lesions(SSLs).METHODS The subjects were patients who underwent pancolonic chromoendoscopy using the EVIS X1 video system center between May 2023 and October 2024.The patients were divided into the new(CF-XZ1200/CF-EZ1500)and 290 series(CF-HQ290Z/PCF-H290Z)groups.Propensity score matching was performed for age,sex,examination purpose,endoscopist,preparation,TXI use,and CAD use.The effects of the scope were analyzed in terms of the ADR,SSL detection rate(SDR),and mean number of adenomas per colonoscopy(APC).RESULTS Of the 7014 patients enrolled,2138 pairs were extracted by propensity score matching(mean age 55.4 years,45.5%male).The new scopes group had a significantly higher ADR than the 290 series group[51.5%vs 45.5%,odds ratio(OR)=1.27,95%CI:1.13-1.43,P<0.001].Similarly,the new scopes group had significantly higher SDR(7.8%vs 5.7%,OR=1.41,95%CI:1.11-1.80,P=0.005)and APC(0.90 vs 0.76,OR=1.11,95%CI:1.05-1.17,P<0.001)than the 290 series group.CONCLUSION In conclusion,the new scope(CF-XZ1200/CF-EZ1500)enhanced the detection of adenomas and SSLs compared to the old ones(290 series). 展开更多
关键词 COLONOSCOPY New generation Adenoma detection rate Propensity-score matching EVIS X1
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Simple synthesis of hollow CoFe carbon fiber composites with enhanced heterogeneous interfaces and impedance matching for broadband microwave absorption
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作者 Yunmin Zhao Lihong Wang +5 位作者 Zhilong Liu Jianxin Ren Haojin Wang Jianqiao Hu Hongtao Guan Yude Wang 《Journal of Materials Science & Technology》 2025年第35期178-190,共13页
One-dimensional(1D)carbon nanofibers with unique three-dimensional(3D)network structure and high electrical conductivity are an important microwave absorbing material.However,due to poor impedance matching and single ... One-dimensional(1D)carbon nanofibers with unique three-dimensional(3D)network structure and high electrical conductivity are an important microwave absorbing material.However,due to poor impedance matching and single loss mechanism,its effective absorption bandwidth(EAB)is limited.Therefore,in this work,a porous hollow carbon fiber is designed using coaxial electrostatic spinning,and the magnetic component CoFe alloy is introduced during high temperature sintering to prepare porous CoFe hollow carbon fiber composite(CF@HCF).Its unique 1D nanostructure and 3D interconnected structure facili-tates multiple reflection losses of electromagnetic waves within the material.In addition,the presence of porous and hollow structures increases heterogeneous interfaces and surface area.The introduction of magnetic components on carbon fibers not only increases the magnetic loss,but also forms a variety of heterogeneous interfaces.In addition,the porous hollow structure improves the spatial efficiency and porosity of the composites,thus optimizing impedance matching.The results indicate that,at a filler ra-tio of 25 wt%,the EAB reaches 7.04 GHz,with a minimum reflection loss(RL_(min))of−50.04 dB under a matching thickness of 2.4 mm.In addition,to extend practical applications,CF@HCF composite membrane with excellent flexibility was prepared using PDMS encapsulation technology,and the sample also shows an average electromagnetic shielding performance of>30 dB.Besides,the radar cross section(RCS)val-ues are below−10 dB m²,demonstrating the material’s significant radar wave attenuation capability and practical application potential.This work provides some perspectives on the preparation of hollow carbon fiber magnetic powder composites,and lays the foundation for the application of magnetic carbon-based composites. 展开更多
关键词 Hollow carbon fiber Heterogeneous interface Impedance matching FLEXIBILITY Radar cross-section simulation
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Research on indoor positioning and navigating technology based on scale hierarchical visual image feature matching
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作者 BIE Haoze QIN Danyang +1 位作者 YANG Jiaqiang LI Sitong 《High Technology Letters》 2025年第2期164-174,共11页
The impact of location services on people’s lives has grown significantly in the era of widespread smart device usage.Due to global navigation satellite system(GNSS)signal rejection,weak signal strength in indoor env... The impact of location services on people’s lives has grown significantly in the era of widespread smart device usage.Due to global navigation satellite system(GNSS)signal rejection,weak signal strength in indoor environments and radio signal interference caused by multiwall environments,which collectively lead to significant positioning errors,vision-based positioning has emerged as a crucial method in indoor positioning research.This paper introduces a scale hierarchical matching model to tackle challenges associated with large visual databases and high scene similarity,both of which will compromise matching accuracy and lead to prolonged positioning delays.The proposed model establishes an image feature database using GIST features and speeded up robust feature(SURF)in the offline stage.In the online stage,a positioning navigating algorithm is constructed based on Dijkstra’s path planning.Additionally,a corresponding Android application has been developed to facilitate visual positioning and navigation in indoor environments.Experimental results obtained in real indoor environments demonstrate that the proposed method significantly enhances positioning accuracy compared with similar algorithms,while effectively reducing time overhead.This improvement caters to the requirements for indoor positioning and navigation,thereby meeting user needs. 展开更多
关键词 visual feature scale hierarchy feature matching indoor positioning indoor navigation
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Effectiveness of Pentavalent Rotavirus Vaccine-a Propensity Score Matched Test Negative Design Case-Control Study Using Medical Big Data in Three Provinces of China
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作者 Yuexin Xiu Lin Tang +10 位作者 Fuzhen Wang Lei Wang Zhen Li Jun Liu Dan Li Xueyan Li Yao Yi Fan Zhang Lei Yu Jingfeng Wu Zundong Yin 《Biomedical and Environmental Sciences》 2025年第9期1032-1043,共12页
Objective The objective of our study was to evaluate the vaccine effectiveness(VE)of the pentavalent rotavirus vaccine(RV5)among<5-year-old children in three provinces of China during 2020-2024 via a propensity sco... Objective The objective of our study was to evaluate the vaccine effectiveness(VE)of the pentavalent rotavirus vaccine(RV5)among<5-year-old children in three provinces of China during 2020-2024 via a propensity score-matched test-negative case-control study.Methods Electronic health records and immunization information systems were used to obtain data on acute gastroenteritis(AGE)cases tested for rotavirus(RV)infection.RV-positive cases were propensity score matched with RV-negative controls for age,visit month,and province.Results The study included 27,472 children with AGE aged 8 weeks to 4 years at the time of AGE diagnosis;7.98%(2,192)were RV-positive.The VE(95%confidence interval,CI)of 1-2 and 3 doses of RV5 against any medically attended RV infection(inpatient or outpatient)was 57.6%(39.8%,70.2%)and 67.2%(60.3%,72.9%),respectively.Among children who received the 3rd dose before turning 5 months of age,3-dose VE decreased from 70.4%(53.9%,81.1%)(<5 months since the 3rd dose)to 63.0%(49.1%,73.0%)(≥1 year since the 3rd dose).The three-dose VE rate was 69.4%(41.3%,84.0%)for RVGE hospitalization and 57.5%(38.9%,70.5%)for outpatient-only medically attended RVGE.Conclusion Three-dose RV5 VE against rotavirus gastroenteritis(RVGE)in children aged<5 years was higher than 1-2-dose VE.Three-dose VE decreased with time since the 3rd dose in children who received the 3rd dose before turning five months of age,but remained above 60%for at least one year.VE was higher for RVGE hospitalizations than for medically attended outpatient visits. 展开更多
关键词 Rotavirus vaccine Vaccine effectiveness Test-negative design Propensity score matching
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Damage Detection of the Pipes Conveying Fluid on the Pasternak Foundation Using the Matching Pursuit Method
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作者 Nahid Khomarian Ramazan-Ali Jafari-Talookolaei +1 位作者 Morteza Saadatmorad Reza Haghani 《哈尔滨工程大学学报(英文版)》 2025年第6期1122-1140,共19页
The current study examines damage detection in fluid-conveying pipes supported on a Pasternak foundation.This study proposes a novel method that uses the matching pursuit(MP)algorithm for damage detection.The governin... The current study examines damage detection in fluid-conveying pipes supported on a Pasternak foundation.This study proposes a novel method that uses the matching pursuit(MP)algorithm for damage detection.The governing equations of motion for the pipe are derived using Hamilton’s principle.The finite element method,combined with the Galerkin approach,is employed to obtain the mass,damping,and stiffness matrices.To identify damage locations through pipe mode-shape decomposition,an index called the“matching pursuit residual”is introduced as a novel contribution of this study.The proposed method facilitates damage detection at various levels and locations under different boundary conditions.The findings demonstrate that the MP residual damage index can accurately localize damage in the pipes.Furthermore,the results of the numerical and experimental tests showcase the efficiency of the proposed method,highlighting that the MP signal approximation algorithm effectively detects damage in structures. 展开更多
关键词 Damage detection matching pursuit Damaged pipe Galerkin method Finite element method
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