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基于Blocked force方法的结构振动响应预测 被引量:1
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作者 刘念思 翁建生 郑子健 《振动与冲击》 EI CSCD 北大核心 2020年第21期126-131,共6页
振动噪声源特性识别一直是汽车开发中的重要任务,针对传统传递路径分析中获取激励的局限性,提出了基于Blocked force方法的传递路径分析方法,可以直接测得等效力代替激励源分析结构振动。对Blocked force方法进行理论推导,验证了理论的... 振动噪声源特性识别一直是汽车开发中的重要任务,针对传统传递路径分析中获取激励的局限性,提出了基于Blocked force方法的传递路径分析方法,可以直接测得等效力代替激励源分析结构振动。对Blocked force方法进行理论推导,验证了理论的准确性。针对电子制动助力器工作激励引起的结构噪声问题进行应用研究,选取前围板振动加速度作为研究对象。结果表明,该方法预测的前围板振动响应和试验测试值吻合,验证了Blocked force方法的工程可行性,为整车开发中电子制动助力器结构噪声优化提供理论依据。 展开更多
关键词 传递路径分析 结构噪声 blocked force 响应预测
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A Cross Layer Protocol for Fast Identification of Blocked Tags in Large-Scale RFID Systems 被引量:2
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作者 Chu Chu Zhong Huang +2 位作者 Rui Xu Guangjun Wen Lilan Liu 《Computers, Materials & Continua》 SCIE EI 2020年第9期1705-1724,共20页
Blocker tag attack is one of the denial-of-service(DoS)attacks that threatens the privacy and security of RFID systems.The attacker interferes with the blocked tag by simulating a fake tag with the same ID,thus causin... Blocker tag attack is one of the denial-of-service(DoS)attacks that threatens the privacy and security of RFID systems.The attacker interferes with the blocked tag by simulating a fake tag with the same ID,thus causing a collision of message replies.In many practical scenarios,the number of blocked tags may vary,or even be small.For example,the attacker may only block the important customers or high-value items.To avoid the disclosure of privacy and economic losses,it is of great importance to fast pinpoint these blocked ones.However,existing works do not take into account the impact of the number of blocked tags on the execution time and suffer from incomplete identification of blocked tags,long identification time or privacy leakage.To overcome these limits,we propose a cross layer blocked tag identification protocol(CLBI).CLBI consists of multiple rounds,in which it enables multiple unblocked tags to select one time slot and concurrently verify them by using tag estimation in physical layer.Benefiting from the utilization of most collision slots,the execution time can be greatly reduced.Furthermore,for efficient identification of blocked tags under different proportions,we propose a hybrid protocol named adaptive cross layer blocked tag identification protocol(A-CLBI),which estimates the remaining blocked tag in each round and adjusts the identification strategy accordingly.Extensive simulations show that our protocol outperforms state-of-the-art blocked tags identification protocol. 展开更多
关键词 RFID blocked tag physical layer ESTIMATION IDENTIFICATION
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CURE CHARACTERISTICS OF HYDROXYL TERMINATED POLYBUTADIENE PREPOLYMER WITH BLOCKED TOLUENE DIISOCYANATE-Ⅰ 被引量:1
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作者 Prathima Kamath M.Srinivasan V.N.Krishnamurthy 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1993年第3期284-291,共8页
Controlled release of TDI and hence the cure characteristics of several blocked TDI with HTPB are reported. The reactions were followed through viscosity measurements as a function of time and temperature under the ca... Controlled release of TDI and hence the cure characteristics of several blocked TDI with HTPB are reported. The reactions were followed through viscosity measurements as a function of time and temperature under the catalytic influence of triethylamine. The effect of nature of substituents present on the end capping substrate, temperature, solvent, basicity of catalyst and kinetics thereon have been studied. 展开更多
关键词 blocked TDI HTPB Cure characteristics Toluene diisocyanate
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CURE CHARACTERISTICS OF HYDROXYL TERMINATED POLYBUTADIENE PREPOLYMER WITH BLOCKED TOLUENE DIISOCYANATE-Ⅱ
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作者 Prathima Kamath M.Srinivasan V.N.Krishnamurthy 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1994年第1期91-97,共7页
Cure characteristics of hydroxyl terminated polybutadiene (HTPB) prepolymer with avariety of blocked toluene diisocyanate (TDI) in the presence of triethylamine (TEA) andchloroacetic acid catalyst are reported. Phenol... Cure characteristics of hydroxyl terminated polybutadiene (HTPB) prepolymer with avariety of blocked toluene diisocyanate (TDI) in the presence of triethylamine (TEA) andchloroacetic acid catalyst are reported. Phenol, thiophenol, p-chloropheno1, p-nitrophenol,p-cresol, resorcinol, naphthols, caprolactam and butylated-hydroxytoluene were used as blockingagents. Viscosity measurements have been carried out using a mixture of HTPB and blocked TDIin cyclohexanone in the presence of the catalysts at 50℃ and 60℃ using Haake rotational vis-cometer. Viscosity measurements have also been carried out with 50% solids such as ammonium sulphate along with HTPB and TDI adduct. 展开更多
关键词 Hydroxyl terminated polybutadiene blocked toluene diisocyanate Cure characteristics
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RADIATION INDUCED MICRONUCLEI IN CYTOKINESIS-BLOCKED HUMAN LYMPHOCYTES
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《癌变·畸变·突变》 CAS CSCD 1991年第S1期76-76,共1页
The dose-effect relationship of the fre-quencies of micronuclei was studied in cy-tokinesis-blocked human lymphocytes afterin vitro irradiation of 180 kVp X-rays.Thebest fit in the dose range of 1-5 Gy waslinear-quadr... The dose-effect relationship of the fre-quencies of micronuclei was studied in cy-tokinesis-blocked human lymphocytes afterin vitro irradiation of 180 kVp X-rays.Thebest fit in the dose range of 1-5 Gy waslinear-quadratic.The micronuclei rate ofthe present results was compared with 展开更多
关键词 IRRADIATION blocked QUADRATIC doses LOWER
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Delay of ZGA initiation occurred in 2-cell blocked mouse embryos 被引量:7
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作者 JIAJINGQIU WUWENZHANG +3 位作者 ZHILIWU YIHONGWANG MINQIAN YIPINGLI 《Cell Research》 SCIE CAS CSCD 2003年第3期179-185,共7页
One-cell mouse embryos from KM strain and B6C3F1 strain were cultured in M16 medium, in which 2-cell block generally occurs. Embryos of KM strain exhibited 2-cell block, whereas B6C3F1 embryos, which are regarded as a... One-cell mouse embryos from KM strain and B6C3F1 strain were cultured in M16 medium, in which 2-cell block generally occurs. Embryos of KM strain exhibited 2-cell block, whereas B6C3F1 embryos, which are regarded as a nonblocking strain, proceeded to the 4-cell stage in our culture condition. It is often assumed that the block of early development is due to the failure of/ygotic gene activation (ZGA) in cultured embryos. In this study we examined protein synthesis patterns by two-dimensional gel eleetrophoresis of [35 S] methionine radiolabeled 2-cell embryos. Embryos from the blocking strain and the nonblocking strain were compared in their development both in vitro and in vivo. The detection of TRC expression, a marker of ZGA. at 42 h post hCG in KM embryos developed in vitro suggested that ZGA was also initiated even in the 2-cell arrested embryos. Nevertheless, a significant delay of ZGA was observed in KM strain as compared with normally developed B6C3F1 embryos. At the very beginning of major ZGA as early as 36 h post hCG, TRC has already been expressed in B6C3F1 embryos developed in vitro and KM embryos developed in vivo. But for 2-cell blocked KM embryos, TRC was still not detectable even at 38 h post hCG. These evidences suggest that 2-cell-blocked embryos do initiate ZGA, and that 2-cell block phenomenon is due not to the disability in initiating ZGA. but to a delay of ZGA. 展开更多
关键词 monse embryo two-cell block zygotic gone activation (ZGA).
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Efficient blocked symmetric compressed sparse column method for finite element analysis
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作者 Yingjun WANG Shijie LUO +1 位作者 Jinyu GU Yuanfang ZHANG 《Frontiers of Mechanical Engineering》 2025年第1期87-104,共18页
In finite element analysis(FEA),optimizing the storage requirements of the global stiffness matrix and enhancing the computational efficiency of solving finite element equations are pivotal objectives.To address these... In finite element analysis(FEA),optimizing the storage requirements of the global stiffness matrix and enhancing the computational efficiency of solving finite element equations are pivotal objectives.To address these goals,we present a novel method for compressing the storage of the global stiffness matrix,aimed at minimizing memory consumption and enhancing FEA efficiency.This method leverages the block symmetry of the global stiffness matrix,hence named the blocked symmetric compressed sparse column(BSCSC)method.We also detail the implementation scheme of the BSCSC method and the corresponding finite element equation solution method.This approach optimizes only the global stiffness matrix index,thereby reducing memory requirements without compromising FEA computational accuracy.We then demonstrate the efficiency and memory savings of the BSCSC method in FEA using 2D and 3D cantilever beams as examples.In addition,we employ the BSCSC method to an engine connecting rod model to showcase its superiority in solving complex engineering models.Furthermore,we extend the BSCSC method to isogeometric analysis and validate its scalability through two examples,achieving up to 66.13%memory reduction and up to 72.06%decrease in total computation time compared to the traditional compressed sparse column method. 展开更多
关键词 finite element analysis global stiffness matrix blocked symmetric property memory reduction isogeometric analysis
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Progress and challenges in blocked impurity band infrared detectors for space-based astronomy 被引量:5
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作者 Yunlong Xiao He Zhu +9 位作者 Ke Deng Peng Wang Qing Li Ting He Tao Zhang Jinshui Miao Ning Li Wei Lu Ning Dai Weida Hu 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS CSCD 2022年第8期45-61,共17页
Astronomical detection at infrared wavelengths is crucial in astrophysics due to the critical information in this wavelength range.Blocked impurity band(BIB) infrared detectors are desirable for space-based astronomic... Astronomical detection at infrared wavelengths is crucial in astrophysics due to the critical information in this wavelength range.Blocked impurity band(BIB) infrared detectors are desirable for space-based astronomical observation due to their broad response range, low dark currents, high quantum efficiencies, and excellent radiation resistance. In this review, typical BIB device structures and device physics development are first introduced. Subsequently, we discuss progress in Si-based BIB detectors with different doping types and emphasize their applications in space-based infrared detection. Additionally, we discuss recent efforts on pixel performance optimization, response extension, and higher operating temperature devices. Finally,we conclude by proposing the challenges and perspectives of BIB detectors with improved detection performances. 展开更多
关键词 space-based astronomical infrared detection blocked impurity band infrared detectors hopping conduction low background
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Hyponormal Block Toeplitz Operators on the Weighted Bergman Space with Circulant Symbols
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作者 FU Guangyang ZHOU Jiang 《数学进展》 北大核心 2026年第1期183-191,共9页
In this paper,we present a necessary and sufficient condition for hyponormal block Toeplitz operators T on the vector-valued weighted Bergman space with symbolsΦ(z)=G^(*)(z)+F(z),where F(z)=∑^(N)_(i)=1 A_(i)z^(i)and... In this paper,we present a necessary and sufficient condition for hyponormal block Toeplitz operators T on the vector-valued weighted Bergman space with symbolsΦ(z)=G^(*)(z)+F(z),where F(z)=∑^(N)_(i)=1 A_(i)z^(i)and G(z)=∑^(N)_(i)=1 A_(−i)z^(i),A_(i)ae culants. 展开更多
关键词 block Toeplitz operator hyponormal weighted Bergman space CIRCULANT COMMUTATOR
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In vitro inhibitory effect of CD_8^+ cells from patients with aplastic anemia on normal CFU-GM growth was blocked by cimetidine
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作者 汪明春 杨力建 +2 位作者 郭秀枝 陈少华 廖继东 《Chinese Medical Journal》 SCIE CAS CSCD 1998年第2期4-4,共1页
Objective To investigate the effect of histamine type Ⅱ (H 2) receptors of the CD + 8 cells from aplastic anemia (AA) patients on the inhibition of hematopoiesis. Methods Employing the modification of the panni... Objective To investigate the effect of histamine type Ⅱ (H 2) receptors of the CD + 8 cells from aplastic anemia (AA) patients on the inhibition of hematopoiesis. Methods Employing the modification of the panning method with monoclonal antibody the CD + 8 cells from peri pheral blood mononulcear cells of 17 aplastic anemia patients were obtained. The ribs moved during thoracic operations from 17 patients with non hematologic diseases were as normal bone marrow resource. According to different group 2×10 4/ml CD + 8 cells from AA patients and/or 1.0×10 5 mol/L or 0.5×10 5 mol/L cimetidine alone or in combination were added in the normal CFU GM cultures. Reusults The normal CFU GM from the rib bone marrows was 147.69±24.75/10 5 cells (±s), if 2×10 4/ml CD + 8 cells from AA patients were added in the cultures, the CFU GM formation significantly decreased (89.49±20.49/10 5 cells, P<0.01). If CD + 8 cells from AA patients and 1.0×10 5 mol/L or 0.5×10 5 mol/L cimetidine were in combination added in the cultures, the CFU GM were 144.96±25.34/10 5 cells or 156.28± 32.81/10 5 cells respectively, compared with normal group P>0.05. If 1.0×10 5 mol/L or 0.5×10 5 mol/L cimetidine was added alone in the cultures, the CFU GM number were 110.47±27.46/10 5 cells (compared with control P<0.01) or 160.06±32.22/10 5 cells (compared with control P>0.05) respectively. Conclusion 1.0×10 5 mol/L and 0.5×10 5 mol/L H 2 receptor antagonist cimetidine completely abolished the suppressive effect of CD + 8 cells from AA patients on the growth of normal CFU GM and lower concentration cimetidine (0.5×10 5 mol/L) didn't suppress the growth of normal CFU GM. 展开更多
关键词 ANEMIA APLASTIC blocked 汪明 陈少华
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Hypothesis Testing for Independence Under Blocked Compound Symmetric Covariance Structure
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作者 Shin-ichi Tsukada 《Communications in Mathematics and Statistics》 SCIE 2018年第2期163-184,共22页
One type of covariance structure is known as blocked compound symmetry.Recently,Roy et al.(J Multivar Anal 144:81–90,2016)showed that,assuming this covariance structure,unbiased estimators are optimal under normality... One type of covariance structure is known as blocked compound symmetry.Recently,Roy et al.(J Multivar Anal 144:81–90,2016)showed that,assuming this covariance structure,unbiased estimators are optimal under normality and described hypothesis testing for independence as an open problem.In this paper,we derive the distributions of unbiased estimators and consider hypothesis testing for independence.Representative test statistics such as the likelihood ratio criterion,Waldstatistic,Rao’s score statistic,and gradient statistic are derived,and we evaluate the accuracy of the test using these statistics through numerical simulations.The power of the Wald test is the largest when the dimension is high,and the power of the likelihood ratio test is the largest when the dimension is low. 展开更多
关键词 Hypothesis testing Asymptotic distribution INDEPENDENCE blocked compound symmetric covariance structure
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A case report with the progression from atrial fibrillation to complete AV block, heart failure and electrical storm
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作者 Shi-Xing LI Xiang-Min SHI +1 位作者 Jian LI Chuang ZHANG 《Journal of Geriatric Cardiology》 2026年第1期65-68,共4页
When patients initially present with atrial fibrillation along with an enlarged heart and heart failure, followed by atrioventricular block, it's essential to consider genetic factors.^([1])Genetic testing can off... When patients initially present with atrial fibrillation along with an enlarged heart and heart failure, followed by atrioventricular block, it's essential to consider genetic factors.^([1])Genetic testing can offer crucial diagnostic evidence, aiding in prognosis assessment and the adoption of appropriate treatment strategies. 展开更多
关键词 heart failure atrial fibrillation enlarged heart atrioventricular block genetic factors genetic testing adoption appropriate treatment strategies complete av block prognosis assessment
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Engineering repairable nanoporous functional coatings on arbitrary substrates by manipulating phase behaviors of block copolymers
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作者 Jiemei Zhou Xiang Ying +3 位作者 Daiwen Li Mingjie Wei Xiangyue Ye Yong Wang 《Chinese Journal of Chemical Engineering》 2026年第1期36-46,共11页
Nanoporous polymers are extensively coated on various substrates to deliver optical,permselective,or other functions.However,it remains desired to fast produce uniform nanoporous polymer coatings on substrates with co... Nanoporous polymers are extensively coated on various substrates to deliver optical,permselective,or other functions.However,it remains desired to fast produce uniform nanoporous polymer coatings on substrates with complex surfaces.Herein,by manipulating the interactions between block copolymers and selective solvents,we prepare repairable nanoporous polymers on arbitrary substrates.This is realized by an extremely simple sequential coating process:sequential coating of block copolymers and their swelling agents on substrate surfaces.The swelling agents are comprised of two solvents that swell the constituent blocks of the copolymers to different degrees,rapidly producing polymer coatings with uniform,interconnected,sub-50 nm pores.This sequential coating process is able to conformally build nanoporous polymers on nonplanar substrates with large lateral sizes and complex surface features,and also to in situ repair defects arising during usages.We further demonstrate that the nanoporous coatings show excellent antireflective and membrane separation performances.This sequential coating process is dictated by polymer–solvent interactions,and is expected to find applications in diverse fields for its simplicity,adaptability,and the capability to produce well-defined nanoporosities. 展开更多
关键词 Nanoporous coating Block copolymers Selective swelling Polymer-solvent interactions ANTIREFLECTION
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The Enhancement of Mechanical Stretchability for Stretchable Organic Solar Cells
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作者 WANG Minshuai CAI Xiaomei ZHENG Kai 《Journal of Wuhan University of Technology(Materials Science)》 2026年第2期547-552,共6页
To evaluate their performance,we constructed organic solar cells using PTB7/Y6 and PTB7-b-PNDI active layers,which were deposited on PET substrates coated with PEDOT:PSS.The ternary solar cells demonstrated an excelle... To evaluate their performance,we constructed organic solar cells using PTB7/Y6 and PTB7-b-PNDI active layers,which were deposited on PET substrates coated with PEDOT:PSS.The ternary solar cells demonstrated an excellent power conversion efficiency after being stretched by 38%.The stretchable organic solar cells were spin-coated on the flexible substrate.The electrodes were formed via liquid metal dropcoating.Solar cell devices based on PET/PH1000/PEDOT:PSS and PTB7:Y6:5% BCP active layer materials show better stretchability than the normal solar cells.The PTB7:Y6:5% BCP-based stretchable organic solar cell achieves a high PCE of 12.3%,and a PCE of 7.8% after stretching.Incorporating block copolymer additives improves the mechanical properties of organic solar cells,thereby enabling superior stretchability. 展开更多
关键词 STRETCHABLE organic photovoltaics mechanical properties block copolymer
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Engineering stimuli-responsive block copolymers for multimodal bioimaging
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作者 Lizhuang Zhong Ming Liu +3 位作者 Shilong Su Dongxin Zeng Jing Hu Zhiqian Guo 《Chinese Chemical Letters》 2026年第1期116-124,共9页
The diagnostic efficacy of contemporary bioimaging technologies remains constrained by inherent limitations of conventional imaging agents,including suboptimal sensitivity,off-target biodistribution,and inherent cytot... The diagnostic efficacy of contemporary bioimaging technologies remains constrained by inherent limitations of conventional imaging agents,including suboptimal sensitivity,off-target biodistribution,and inherent cytotoxicity.These limitations have catalyzed the development of intelligent stimuli-responsive block copolymers-based bioimaging agents,which was engineered to dynamically respond to endogenous biochemical cues(e.g.,p H gradients,redox potential,enzyme activity,hypoxia environment) or exogenous physical triggers(e.g.,photoirradiation,thermal gradients,ultrasound(US)/magnetic stimuli).Through spatiotemporally controlled structural transformations,stimuli-responsive block copolymers enable precise contrast targeting,activatable signal amplification,and theranostic integration,thereby substantially enhancing signal-to-noise ratios of bioimaging and diagnostic specificity.Hence,this mini-review systematically examines molecular engineering principles for designing p H-,redox-,enzyme-,light-,thermo-,and US/magnetic-responsive polymers,with emphasis on structure-property relationships governing imaging performance modulation.Furthermore,we critically analyze emerging strategies for optical imaging,US synergies,and magnetic resonance imaging(MRI).Multimodal bioimaging has also been elaborated,which could overcome the inherent trade-offs between resolution,penetration depth,and functional specificity in single-modal approaches.By elucidating mechanistic insights and translational challenges,this mini-review aims to establish a design framework of stimuli-responsive block copolymersbased for high fidelity bioimaging agents and accelerate their clinical translation in precise diagnosis and therapy. 展开更多
关键词 STIMULI-RESPONSIVE Block copolymers Molecular engineering Multimodal bioimaging Diagnosis and therapy
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FDEFusion:End-to-End Infrared and Visible Image Fusion Method Based on Frequency Decomposition and Enhancement
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作者 Ming Chen Guoqiang Ma +3 位作者 Ping Qi Fucheng Wang Lin Shen Xiaoya Pi 《Computers, Materials & Continua》 2026年第4期817-839,共23页
In the image fusion field,fusing infrared images(IRIs)and visible images(VIs)excelled is a key area.The differences between IRIs and VIs make it challenging to fuse both types into a high-quality image.Accordingly,eff... In the image fusion field,fusing infrared images(IRIs)and visible images(VIs)excelled is a key area.The differences between IRIs and VIs make it challenging to fuse both types into a high-quality image.Accordingly,efficiently combining the advantages of both images while overcoming their shortcomings is necessary.To handle this challenge,we developed an end-to-end IRI andVI fusionmethod based on frequency decomposition and enhancement.By applying concepts from frequency domain analysis,we used the layering mechanism to better capture the salient thermal targets from the IRIs and the rich textural information from the VIs,respectively,significantly boosting the image fusion quality and effectiveness.In addition,the backbone network combined Restormer Blocks and Dense Blocks;Restormer blocks utilize global attention to extract shallow features.Meanwhile,Dense Blocks ensure the integration between shallow and deep features,thereby avoiding the loss of shallow attributes.Extensive experiments on TNO and MSRS datasets demonstrated that the suggested method achieved state-of-the-art(SOTA)performance in various metrics:Entropy(EN),Mutual Information(MI),Standard Deviation(SD),The Structural Similarity Index Measure(SSIM),Fusion quality(Qabf),MI of the pixel(FMI_(pixel)),and modified Visual Information Fidelity(VIF_(m)). 展开更多
关键词 Infrared images visible images frequency decomposition restormer blocks global attention
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Unraveling the exhumation history of the source terrains of the western Jianghan Basin(Central China)through detrital zircon fission track dating
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作者 HAN Siyu LIN Xu +1 位作者 LIU Weiming LIU Haijin 《Journal of Mountain Science》 2026年第1期49-66,共18页
The Jianghan Basin,at the junction of the Jiangnan and Qinling-Dabie orogenic belts,has a complete Cretaceous to Paleogene stratigraphic record.However,the exhumation history of its source terrains is not well underst... The Jianghan Basin,at the junction of the Jiangnan and Qinling-Dabie orogenic belts,has a complete Cretaceous to Paleogene stratigraphic record.However,the exhumation history of its source terrains is not well understood.We conducted fission track age analysis on zircon grains(n=441)from the Cretaceous and Paleogene strata in the western Jianghan Basin.The Radial Plotter software is utilized to identify peak ages that indicate thermal events and the history of exhumation.The oldest peak at 810 Ma records the Neoproterozoic collisional orogeny between the Yangtze Craton and Cathaysian Block.Ages of 645-558 Ma reflect the convergence between the South China Block and Gondwana.Early Paleozoic ages document the collision leading to the exhumation of the western Jiangnan Orogenic Belt.Late Paleozoic to early Mesozoic peak ages correspond to the Indosinian orogeny.During the Mesozoic,the subduction of the Paleo-Pacific Plate resulted in further exhumation.The absence of Paleogene zircon fission track peak ages in the basin strata suggests limited exhumation during this period,likely due to tectonic quiescence and arid climatic conditions. 展开更多
关键词 Jianghan Basin Detrital zircon Fission track PALEOGEOGRAPHY South China Block
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TP-ViT:truncated uniform-log2 quantizer and progressive bit-decline reconstruction for vision Transformer quantization
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作者 Xichuan ZHOU Sihuan ZHAO +4 位作者 Rui DING Jiayu SHI Jing NIE Lihui CHEN Haijun LIU 《ENGINEERING Information Technology & Electronic Engineering》 2026年第1期47-58,共12页
Vision Transformers(ViTs)have achieved remarkable success across various artificial intelligence-based computer vision applications.However,their demanding computational and memory requirements pose significant challe... Vision Transformers(ViTs)have achieved remarkable success across various artificial intelligence-based computer vision applications.However,their demanding computational and memory requirements pose significant challenges for de-ployment on resource-constrained edge devices.Although post-training quantization(PTQ)provides a promising solution by reducing model precision with minimal calibration data,aggressive low-bit quantization typically leads to substantial perfor-mance degradation.To address this challenge,we present the truncated uniform-log2 quantizer and progressive bit-decline reconstruction method for vision Transformer quantization(TP-ViT).It is an innovative PTQ framework specifically designed for ViTs,featuring two key technical contributions:(1)truncated uniform-log2 quantizer,a novel quantization approach which effectively handles outlier values in post-Softmax activations,significantly reducing quantization errors;(2)bit-decline optimiza-tion strategy,which employs transition weights to gradually reduce bit precision while maintaining model performance under extreme quantization conditions.Comprehensive experiments on image classification,object detection,and instance segmenta-tion tasks demonstrate TP-ViT’s superior performance compared to state-of-the-art PTQ methods,particularly in challenging 3-bit quantization scenarios.Our framework achieves a notable 6.18 percentage points improvement in top-1 accuracy for ViT-small under 3-bit quantization.These results validate TP-ViT’s robustness and general applicability,paving the way for more efficient deployment of ViT models in computer vision applications on edge hardware. 展开更多
关键词 Vision Transformers Post-training quantization Block reconstruction Image classification Object detection Instance segmentation
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Metamorphic P-T-t Evolution and Tectonic Implications of High-pressure Granulites in the Qushan Islands,East China Sea
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作者 CAO Yiwen ZHOU Xiwen +1 位作者 DONG Jie DENG Xuanyu 《Acta Geologica Sinica(English Edition)》 2026年第1期69-81,共13页
Debate has persisted over whether the metamorphic basement of the Zhoushan Islands,easternmost Cathaysia Block,is Precambrian.Here,representative metamorphic rocks from the Qushan Islands were investigated using petro... Debate has persisted over whether the metamorphic basement of the Zhoushan Islands,easternmost Cathaysia Block,is Precambrian.Here,representative metamorphic rocks from the Qushan Islands were investigated using petrography,mineral chemistry,phase equilibria modeling and SHRIMP zircon U-Pb dating to constrain their metamorphic evolution and tectonic significance.Both the pelitic granulites(garnet-kyanite-perthite-biotite-quartz)and the mafic granulites(garnet-clinopyroxene-amphibole-plagioclase-quartz)reached high-pressure granulite-facies conditions of 1.2-1.4 GPa/820-900℃,and recorded three metamorphic stages along a clockwise P-T path with post-peak isothermal decompression.This trajectory indicated rapid exhumation of thickened continental crust during collisional orogeny.Metamorphic ages of 254±3 Ma,262±4 Ma and 259±3 Ma were obtained for mafic granulite,pelitic granulite and marble,respectively,and were consistent with the emplacement age of 259±4 Ma for a pegmatite vein.Detrital zircons in metasediments spanned 2706-330 Ma,which constrained the latest deposition to~330 Ma;thus represented mid-Paleozoic sediment metamorphosed during the late Paleozoic rather than Precambrian basement.We conclude that the Indosinian tectonothermal event in the Cathaysia Block had originated from late Paleozoic-early Mesozoic collisional orogeny between the South China Plate to the north and the Indochina Block to the south. 展开更多
关键词 METAMORPHISM high-pressure granulite zircon U-Pb dating Qushan Islands East China Sea Cathaysia Block
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Magnetic fabric of the late Miocene extrusive rocks of the Combia Volcanic Province:Tectonic implications for the northern Andes
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作者 Victor A.Piedrahita Martin Chadima +3 位作者 Jackeline Ramírez Alejandra Tabares Maria I.Marín-Cerón JinHua Li 《Earth and Planetary Physics》 2026年第1期44-56,共13页
The accretion of the Panama-ChocóBlock to the South American Plate partially drove the geological setting of the northern Andes.This event occurred in different collisional stages that are recorded in Oligocene-m... The accretion of the Panama-ChocóBlock to the South American Plate partially drove the geological setting of the northern Andes.This event occurred in different collisional stages that are recorded in Oligocene-middle Miocene deformed rocks of the inter-Andean valley between the Western and Central Cordilleras of Colombia.However,uncertainty remains about the age of the latest accretionary phases of the Panama-ChocóBlock.Poorly studied late Miocene volcanic rocks within the northern inter-Andean valley may provide key information to constrain the temporality of that final collision.Here,we study the deformational features of the~12-6 Ma extrusive rocks of the Combia Volcanic Province located in the northwestern Andes(Colombia).We present anisotropy of magnetic susceptibility(AMS)data for pyroclastic and volcanic rocks within the AmagáBasin,an inter-Andean depression with Oligocene-middle Miocene sedimentary rocks that recorded NW-SE compression and NE-SW simple shear caused by the Panama-ChocóBlock collision.We identified that the magnetic fabrics of the extrusive rocks of the Combia Volcanic Province reveal flow directions that indicate the occurrence of ancient volcanoes in the central axis of the AmagáBasin.Some of these fabrics do not contain any deformational features,whereas others record the same structural regime as the Oligocene-middle Miocene sedimentary rocks.We infer that variations in the intensity of the deformation promoted late Miocene local fault reactivations that,in contrast to the Oligocene-middle Miocene deformational events,did not affect the entire AmagáBasin.Age differences among the studied sections can also explain the different deformational patterns identified in the basin.Both interpretations suggest that the most significant collisional events of the Panama-ChocóBlock occurred in the Oligocene-middle Miocene,whereas the formation of the Combia Volcanic Province may have either followed or coincided with the latest stages of the accretion. 展开更多
关键词 Combia Volcanic Province Panama-ChocóBlock magnetic fabric deformation flow direction
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