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Vector Correlations and Product Rotational Alignments of Reactions Ca+RBr→CaBr+R(R=CH_(3),C_(2) H_(5) and n-C_(3) H_(7)) 被引量:1
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作者 马建军 丛书林 +1 位作者 张志红 王艳秋 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 北大核心 2006年第2期117-122,共6页
The quasiclassical trajectory method is used to study the vector correlations of the reactions Ca+RBr (R=CH3, C2H5 and n-C3H7Br) and the rotational alignment of product CaBr. The product rotational alignment parame... The quasiclassical trajectory method is used to study the vector correlations of the reactions Ca+RBr (R=CH3, C2H5 and n-C3H7Br) and the rotational alignment of product CaBr. The product rotational alignment parameters at different collision energies and the vector correlations between the reagent and product are numerically calculated. The vector correlations are described by using the angle distribution functions P(θr), P(φr), P(θr, φr) and the polarization-dependent differential cross sections (PDDCSs). The peak values of P(θr) of the product CaBr from Ca+CH3Br are larger than those from Ca+C2H5Br and Ca+n-C3H7Br. The peak of P(θr) at φr= 3π/2 is apparently stronger than that at φr= x/2 for the three reactions Ca+RBr. The calculation results show that the rotational angular momentum of the product CaBr is not only aligned, but also oriented along the direction which is perpendicular to the scattering plane.The product CaBr molecules are strongly scattered forward. The orientation and alignment of the product angular momentum will affect the scattering direction of the product molecules to varying degrees. 展开更多
关键词 Quasiclassical trajectory Vector correlation Orientation and alignment
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MECHANICAL PERTURBATION INDUCED MOLECULAR ALIGNMENTS IN A SIDE-CHAIN LIQUID CRYSTALLINE POLYACETYLENE, POLY{10-[4-(4'-METHOXYPHENOXY-CARBOML)PHENOXYCARBONYL]-1-DECYNE}
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作者 Ben-zhong Tang Xiang-xing Kong Xin-de Feng Department of Chemistry, Hong Kong University of Science & Technology, Clear Water Bay, Kowloon, Hong Kong, China Department of Polymer Science & Engineering, College of Chemistry, Peking University, Beijing 100871, China 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1999年第3期289-294,共6页
A new liquid crystalline polyacetylene containing a phenyl benzoate mesogen (5) is synthesized,whose mesomorphic properties are found to be easily 'tunab1e' by simple mechanical perturbation. Thepolymerization... A new liquid crystalline polyacetylene containing a phenyl benzoate mesogen (5) is synthesized,whose mesomorphic properties are found to be easily 'tunab1e' by simple mechanical perturbation. Thepolymerization of 10- [ 4 - (4' -methoxyphenoxycarbonyl )phenoxycarbonyl] - 1 -decyne (4 ) in itiated by theWCl_6-Ph_4Sn/dioxane complex yields polymer 5 with a M_w of 28400. The molecular structure of 5 ischaracterized by NMR, IR, and UV spectroscopy and its liquid crystalline behavior is investigated by DSC,POM, and XRD analysis. Upon mechanical perturbation, 5 exhibits unusual agitation-induced high-strengthdisclinations, shear-induced inversion walls, and solidification-induced banded textures. Such phenomenahave been observed in the main-chain liquid crystalline polymers with rigid backbones, but have seldom beenreported for the side-chain liquid crystalline polymers with flexible backbones, suggesting that the rigidpolyacetylene backbone of 5 plays a constructive role in inducing the novel molecular alignments. 展开更多
关键词 Liquid crystals Side-chain liquid crystalline polymers POLYACETYLENES High-strength disclinations Inversion walls Banded textures Molecular alignments
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Alignments, Topologies, Convex Geometries and Higgs Spaces 被引量:1
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作者 J. M. S. Simoes-Pereira 《Journal of Mathematics and System Science》 2014年第3期158-163,共6页
Aligned spaces generalize topological spaces and generate Higgs spaces. We give a necessary and sufficient condition for a finite aligned space to be a topological space, we prove the existence of two kinds of convex ... Aligned spaces generalize topological spaces and generate Higgs spaces. We give a necessary and sufficient condition for a finite aligned space to be a topological space, we prove the existence of two kinds of convex geometries, and we compare several concepts and results for arbitrary (that is, not necessarily finite) aligned, topological and Higgs spaces. 展开更多
关键词 Aligned space topological space convex geometry Higgs space.
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Translational,vibrational,rotational enhancements and alignments of reactions H + ClF(v = 0-5,j= 0,3,6,9) →HCl + F and HF + Cl,at E_(rel)= 0.5-20 kcal/mol
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作者 赵(吴)为克 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第10期213-225,共13页
Quasi-classical trajectory calculations of the title reactions H + C1F (v = 0-5, j = 0, 3,6, 9) -+ HCl + F and H + C1F (v = 0-5, j =0, 3, 6, 9) → HF + C1 at Erel = 0.5 kcal/mol-20 kcal/mol on ground potentia... Quasi-classical trajectory calculations of the title reactions H + C1F (v = 0-5, j = 0, 3,6, 9) -+ HCl + F and H + C1F (v = 0-5, j =0, 3, 6, 9) → HF + C1 at Erel = 0.5 kcal/mol-20 kcal/mol on ground potential energy surface DHTSN of 1 2AI [M. E Deskevich, M. Y. Hayes, K. Takahashi, R. T. Skodje and D. J. Nesbitt, J. Chem. Phys. 124, 224303 (2006)] are performed. Potential energy surfaces derived from DHTSN for the title reactions are obtained, and compared with that of DHTSN for the reaction F + HC1 -+ HF + C1. Both potential energy surfaces have an early barrier pattern. Integral cross sections and alignments of product molecules HC1 and HF dependent on the internal energy states v and j of reactant molecule C1F are obtained and compared. Translational, vibrational, and rotational energy specific translational enhancements of the reactant molecule CIF of the title reactions are found. Reaction mechanisms of the title reactions according to the respective potential energy contours are further found and explained. Reasons of simultaneous translational and vibrational enhancements are clarified. 展开更多
关键词 quasi-classical trajectory calculation integral cross section alignment TRV enhancement
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LOOSE PHRASE EXTRACTION WITH n-BEST ALIGNMENTS
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作者 Xue Yongzeng Li Sheng 《Journal of Electronics(China)》 2007年第4期567-571,共5页
Loose phrase extraction method is proposed and applied for phrase-based statistical ma- chine translation. The method extracts phrase pairs that are not strictly consistent with word align- ments. Two types of constra... Loose phrase extraction method is proposed and applied for phrase-based statistical ma- chine translation. The method extracts phrase pairs that are not strictly consistent with word align- ments. Two types of constraints on word positions are investigated for this method. Furthermore, n-best alignments are introduced for phrase extraction instead of the one-best. Experimental results show that the proposed approach outperforms the baseline system, Pharaoh system, for both one-best and n-best alignments. 展开更多
关键词 Statistical machine translation Phrase-based ALIGNMENT n-best Phrase extraction
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Beam alignments based on the spectrum decomposition of orbital angular momentums for acoustic-vortex communications
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作者 Gepu Guo Xinjia Li +4 位作者 Qingdong Wang Yuzhi Li Qingyu Ma Juan Tu Dong Zhang 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第12期296-304,共9页
Given the enhanced channel capacity of wave chirality,acoustic communications based on the orbital angular momentum(OAM)of acoustic-vortex(AV)beams are of significant interest for underwater data transmissions.However... Given the enhanced channel capacity of wave chirality,acoustic communications based on the orbital angular momentum(OAM)of acoustic-vortex(AV)beams are of significant interest for underwater data transmissions.However,the stringent beam alignment is required for the coaxial arrangement of transceiver arrays to ensure the accuracy and reliability of OAM decoding.To avoid the required multiple measurements of the traditional orthogonality based algorithm,the beam alignment algorithm based on the OAM spectrum decomposition is proposed for AV communications by using simplified ring-arrays.Numerical studies of the single-OAM and OAM-multiplexed AV beams show that the error of the OAM spectrum increases with the translation distance and the deflection angle of the transceiver arrays.To achieve an ideal arrangement,two methods of the single-array translation alignment and the dual-array deflection alignment are developed based on the least standard deviation of the OAM spectrum(SD-OAM).By decreasing the SD-OAM towards zero using transceiver arrays of 16 transmitters and 16 receivers,accurate beam alignments are accomplished by multiple adjustments in three dimensions.The proposed method is also demonstrated by experimental measurements of the OAM dispersion and the SD-OAM for misaligned beams.The results demonstrate the feasibility of the rapid beam alignment based on the OAM spectrum decomposition by using simplified transceiver ring-arrays,and suggest more application potentials for acoustic communications. 展开更多
关键词 acoustic-vortex beam beam alignment orbital angular momentum(OAM)spectrum least standard deviation acoustic communication
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ORPA:a fast and efficient phylogenetic analysis method for constructing genome-wide alignments of organelle genomes 被引量:1
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作者 Guiqi Bi Xinxin Luan Jianbin Yan 《Journal of Genetics and Genomics》 SCIE CAS CSCD 2024年第3期352-358,共7页
Creating a multi-gene alignment matrix for phylogenetic analysis using organelle genomes involves aligning single-gene datasets manually,a process that can be time-consuming and prone to errors.The HomBlocks pipeline ... Creating a multi-gene alignment matrix for phylogenetic analysis using organelle genomes involves aligning single-gene datasets manually,a process that can be time-consuming and prone to errors.The HomBlocks pipeline has been created to eliminate the inaccuracies arising from manual operations.The processing of a large number of sequences,however,remains a time-consuming task.To conquer this challenge,we develop a speedy and efficient method called Organelle Genomes for Phylogenetic Analysis(ORPA).ORPA can quickly generate multiple sequence alignments for whole-genome comparisons by parsing the result files of NCBI BLAST,completing the task just in 1 min.With increasing data volume,the efficiency of ORPA is even more pronounced,over 300 times faster than HomBlocks in aligning 60 high-plant chloroplast genomes.The phylogenetic tree outputs from ORPA are equivalent to HomBlocks,indicating its outstanding efficiency.Due to its speed and accuracy,ORPA can identify species-level evolutionary conflicts,providing valuable insights into evolutionary cognition. 展开更多
关键词 Ultrafast alignment Organelle phylogenomics Phylogenomic conflict Efficient pipeline Multiple sequence alignment pipeline
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Alignments in the nobelium isotopes 被引量:1
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作者 郑世界 许甫荣 +1 位作者 袁岑溪 亓冲 《Chinese Physics C》 SCIE CAS CSCD 2009年第2期107-109,共3页
Total-Routhian-Surface calculations have been performed to investigate the deformation and alignment properties of the No isotopes. It is found that normal deformed and superdeformed states in these nuclei can coexist... Total-Routhian-Surface calculations have been performed to investigate the deformation and alignment properties of the No isotopes. It is found that normal deformed and superdeformed states in these nuclei can coexist at low excitation energies. In neutron-deficient No isotopes, the superdeformed shapes can even become the ground states. Moreover, we plotted the kinematic moments of inertia of the No isotopes, which follow very nicely available experimental data. It is noted that, as the rotational frequency increases, alignments develop at hω = 0.2- 0.3 MeV. Our calculations show that the occupation of the νj15/2 orbital plays an important role in the alignments of the No isotopes. 展开更多
关键词 superheavy nuclei TRS alignments
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A novel flexible nerve guidance conduit promotes nerve regeneration while providing excellent mechanical properties
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作者 Tong Li Quhan Cheng +11 位作者 Jingai Zhang Boxin Liu Yu Shi Haoxue Wang Lijie Huang Su Zhang Ruixin Zhang Song Wang Guangxu Lu Peifu Tang Zhongyang Liu Kai Wang 《Neural Regeneration Research》 SCIE CAS 2025年第7期2084-2094,共11页
Autografting is the gold standard for surgical repair of nerve defects>5 mm in length;however,autografting is associated with potential complications at the nerve donor site.As an alternative,nerve guidance conduit... Autografting is the gold standard for surgical repair of nerve defects>5 mm in length;however,autografting is associated with potential complications at the nerve donor site.As an alternative,nerve guidance conduits may be used.The ideal conduit should be flexible,resistant to kinks and lumen collapse,and provide physical cues to guide nerve regeneration.We designed a novel flexible conduit using electrospinning technology to create fibers on the innermost surface of the nerve guidance conduit and employed melt spinning to align them.Subsequently,we prepared disordered electrospun fibers outside the aligned fibers and helical melt-spun fibers on the outer wall of the electrospun fiber lumen.The presence of aligned fibers on the inner surface can promote the extension of nerve cells along the fibers.The helical melt-spun fibers on the outer surface can enhance resistance to kinking and compression and provide stability.Our novel conduit promoted nerve regeneration and functional recovery in a rat sciatic nerve defect model,suggesting that it has potential for clinical use in human nerve injuries. 展开更多
关键词 aligned fibers anti-kinking helical fibers nerve guidance conduit nerve regeneration peripheral nerve injury topological guidance
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FASMA:A Service to Format and Analyze Sequences in Multiple Alignments 被引量:1
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作者 Susan Costantini Giovanni Colonna Angelo M.Facchiano 《Genomics, Proteomics & Bioinformatics》 SCIE CAS CSCD 2007年第3期253-255,共3页
Multiple sequence alignments are successfully applied in many studies for understanding the structural and functional relations among single nucleic acids and protein sequences as well as whole families. Because of th... Multiple sequence alignments are successfully applied in many studies for understanding the structural and functional relations among single nucleic acids and protein sequences as well as whole families. Because of the rapid growth of sequence databases, multiple sequence alignments can often be very large and difficult to visualize and analyze. We offer a new service aimed to visualize and analyze the multiple alignments obtained with different external algorithms, with new features useful for the comparison of the aligned sequences as well as for the creation of a final image of the alignment. The service is named FASMA and is available at http: / /bioinformatica.isa.cnr.it /FASMA /. 展开更多
关键词 multiple alignment sequence analysis web tools
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The effect of hadronic scatterings on the measurement of vector meson spin alignments in heavy-ion collisions 被引量:1
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作者 Diyu Shen Jinhui Chen Zi-Wei Lin 《Chinese Physics C》 SCIE CAS CSCD 2021年第5期105-112,共8页
Spin alignments of vector mesons and hyperons in relativistic heavy-ion collisions have been proposed as signals of global polarization.The STAR experiment first observed the ∧ polarization.Recently,the ALICE collabo... Spin alignments of vector mesons and hyperons in relativistic heavy-ion collisions have been proposed as signals of global polarization.The STAR experiment first observed the ∧ polarization.Recently,the ALICE collaboration measured the transverse momentum {PT) and the collision centrality dependence of K*,and Φ spin alignments during Pb-Pb collisions at 1/2sNN=2.76 TeV.A large signal is observed in the low pT region of mid-central collisions for K*,while the signal is much smaller for Φ,and these have not been understood yet.Since vector mesons have different lifetimes and their decay products have different scattering cross sections,they suffer from different hadronic effects.In this paper,we study the effect of hadronic interactions on the spin alignment of K*,Φ,and p mesons in relativistic heavy-ion collisions with a multi-phase transport model.We find that hadronic scatterings lead to a deviation of the observed spin alignment matrix element p00 away from the true value for p and K*mesons(with a bigger effect on p) while the effect is negligible for the Φ meson.The effect depends on the kinematic acceptance:the observed p00 value is lower than the true value when the pseudorapidity(η) coverage is small,while there is little effect when the η coverage is large.Hence,this study provides valuable information to understand the vector meson spin alignment signals observed during the experiments. 展开更多
关键词 heavy-ion collisions global polarization vector meson spin alignment acceptance effect hadronic scatterings
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The number of alignments between two DNA sequences
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作者 Helena Andrade Juan J. Nieto Angela Torres 《International Journal of Biomathematics》 2016年第4期75-80,共6页
We consider two DNA sequences and compare both sequences. One of the crucial issues in bioinformatics is to measure the similarity of two DNA sequences. To this purpose one has to consider different alignments between... We consider two DNA sequences and compare both sequences. One of the crucial issues in bioinformatics is to measure the similarity of two DNA sequences. To this purpose one has to consider different alignments between both sequences. The number of alignments grows very rapidly with the length of the sequences. In this paper we give exact, explicit and computable formulas for the number of different possible alignments and for some classes of reduced alignments. We provide a new insight into the theory of DNA sequence alignment. 展开更多
关键词 DNA sequence ALIGNMENT difference equation.
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多头自注意力机制的Faster R-CNN目标检测算法 被引量:2
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作者 文靖杰 王勇 +1 位作者 李金龙 张渝 《现代电子技术》 北大核心 2024年第7期8-16,共9页
文中提出一种融合多头注意力机制、ROIAlign和Soft-NMS的FasterR-CNN目标检测算法,旨在解决原始Faster R-CNN目标检测网络中存在的检测精度低、漏检、误检的问题。首先,为了提高Faster R-CNN的感知能力,提取特征图中的重要特征并降低对... 文中提出一种融合多头注意力机制、ROIAlign和Soft-NMS的FasterR-CNN目标检测算法,旨在解决原始Faster R-CNN目标检测网络中存在的检测精度低、漏检、误检的问题。首先,为了提高Faster R-CNN的感知能力,提取特征图中的重要特征并降低对无关特征的提取,在网络中嵌入注意力机制;接着,针对共享全连接层的降维操作导致的一些区域的细节信息被忽略,造成局部信息的丢失,采用一维卷积代替共享全连接层实现权重计算的任务,以捕捉更广泛的空间信息;然后为了提供更丰富的特征表达能力,在注意力机制中引入多头机制分别对特征的不同部分进行重要性的加权;为了减少在特征提取时原图信息的丢失,使用ROI Align替换ROI Pooling算法;最后,在算法后处理中引入Soft-NMS替换传统非极大抑制(NMS)算法以减少漏检和误检情况。实验证明,改进后的Faster R-CNN目标检测网络对感兴趣目标的定位能力得到提高,漏检和误检情况减少,平均检测精度得到显著提升。 展开更多
关键词 机器视觉 目标检测 Faster R-CNN ROI Align 多头注意力机制 Soft-NMS
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Highly Aligned Graphene Aerogels for Multifunctional Composites 被引量:1
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作者 Ying Wu Chao An +4 位作者 Yaru Guo Yangyang Zong Naisheng Jiang Qingbin Zheng Zhong‑Zhen Yu 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第6期276-342,共67页
Stemming from the unique in-plane honeycomb lattice structure and the sp^(2)hybridized carbon atoms bonded by exceptionally strong carbon–carbon bonds,graphene exhibits remarkable anisotropic electrical,mechanical,an... Stemming from the unique in-plane honeycomb lattice structure and the sp^(2)hybridized carbon atoms bonded by exceptionally strong carbon–carbon bonds,graphene exhibits remarkable anisotropic electrical,mechanical,and thermal properties.To maximize the utilization of graphene’s in-plane properties,pre-constructed and aligned structures,such as oriented aerogels,films,and fibers,have been designed.The unique combination of aligned structure,high surface area,excellent electrical conductivity,mechanical stability,thermal conductivity,and porous nature of highly aligned graphene aerogels allows for tailored and enhanced performance in specific directions,enabling advancements in diverse fields.This review provides a comprehensive overview of recent advances in highly aligned graphene aerogels and their composites.It highlights the fabrication methods of aligned graphene aerogels and the optimization of alignment which can be estimated both qualitatively and quantitatively.The oriented scaffolds endow graphene aerogels and their composites with anisotropic properties,showing enhanced electrical,mechanical,and thermal properties along the alignment at the sacrifice of the perpendicular direction.This review showcases remarkable properties and applications of aligned graphene aerogels and their composites,such as their suitability for electronics,environmental applications,thermal management,and energy storage.Challenges and potential opportunities are proposed to offer new insights into prospects of this material. 展开更多
关键词 Highly aligned graphene aerogels Quantitative characterization of alignment Multifunctional composites Anisotropic properties Multifunctional applications
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通智测试——基于动态具身物理社会交互环境的通用人工智能测试 被引量:1
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作者 Yujia Peng Jiaheng Han +7 位作者 Zhenliang Zhang Lifeng Fan Tengyu Liu Siyuan Qi Xue Feng Yuxi Ma Yizhou Wang Song-Chun Zhu 《Engineering》 SCIE EI CAS CSCD 2024年第3期12-22,共11页
The release of the generative pre-trained transformer(GPT)series has brought artificial general intelligence(AGI)to the forefront of the artificial intelligence(AI)field once again.However,the questions of how to defi... The release of the generative pre-trained transformer(GPT)series has brought artificial general intelligence(AGI)to the forefront of the artificial intelligence(AI)field once again.However,the questions of how to define and evaluate AGI remain unclear.This perspective article proposes that the evaluation of AGI should be rooted in dynamic embodied physical and social interactions(DEPSI).More specifically,we propose five critical characteristics to be considered as AGI benchmarks and suggest the Tong test as an AGI evaluation system.The Tong test describes a value-and ability-oriented testing system that delineates five levels of AGI milestones through a virtual environment with DEPSI,allowing for infinite task generation.We contrast the Tong test with classical AI testing systems in terms of various aspects and propose a systematic evaluation system to promote standardized,quantitative,and objective benchmarks and evaluation of AGI. 展开更多
关键词 Artificial general intelligence Artificial intelligence benchmark Artificial intelligence evaluation Embodied artificial intelligence Value alignment Turing test CAUSALITY
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Strip steel surface defect detection algorithm based on improved Faster R-CNN 被引量:1
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作者 齐继阳 吴宇帆 《China Welding》 CAS 2024年第2期11-22,共12页
To solve the problems of the low accuracy and poor real-time performance of traditional strip steel surface defect detection meth-ods,which are caused by the characteristics of many kinds,complex shapes,and different ... To solve the problems of the low accuracy and poor real-time performance of traditional strip steel surface defect detection meth-ods,which are caused by the characteristics of many kinds,complex shapes,and different scales of strip surface defects,a strip steel surface defect detection algorithm based on improved Faster R-CNN is proposed.Firstly,the residual convolution module is inserted into the Swin Transformer network module to form the RC-Swin Transformer network module,and the RC-Swin Transformer module is introduced into the backbone network of the traditional Faster R-CNN to enhance the ability of the network to extract the global feature information of the image and adapt to the complex shape of the strip steel surface defect.To improve the attention of the network to defects in the image,a CBAM-BiFPN network module is designed,and then the backbone network is combined with the CBAM-BiFPN network to realize the de-tection and fusion of multi-scale features.The RoI align layer is used instead of the RoI pooling layer to improve the accuracy of defect loca-tion.Finally,Soft NMS is used to achieve non-maximum suppression and remove redundant boxes.In the comparative experiment on the NEU-DET dataset,the improved algorithm improves the mean average precision by 4.2%compared with the Faster R-CNN algorithm,and also improves the average precision by 6.1%and 6.7%for crazing defect and rolled-in scale defect,which are difficult to detect with the Faster R-CNN algorithm.The experiments show that the improvements proposed in the paper effectively improve the detection accuracy of the algorithm and have certain practical value. 展开更多
关键词 defect detection RC-Swin Transformer CBAM-BiFPN RoI align Soft NMS
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Unicompartmental knee arthroplasty vs high tibial osteotomy for knee osteoarthritis:A comparison of clinical and radiological outcomes 被引量:1
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作者 Frederick William Wyatt Oday Al-Dadah 《World Journal of Orthopedics》 2024年第5期444-456,共13页
BACKGROUND Unicompartmental knee arthroplasty(UKA)and high tibial osteotomy(HTO)are well-established operative interventions in the treatment of knee osteoarthritis.However,which intervention is more beneficial to pat... BACKGROUND Unicompartmental knee arthroplasty(UKA)and high tibial osteotomy(HTO)are well-established operative interventions in the treatment of knee osteoarthritis.However,which intervention is more beneficial to patients with knee osteoarthritis remains unknown and a topic of much debate.Simultaneously,there is a paucity of research assessing the relationship between radiographic parameters of knee joint alignment and patient-reported clinical outcomes,preoperatively and following HTO or UKA.AIM To compare UKAs and HTOs as interventions for medial-compartment knee osteoarthritis:Examining differences in clinical outcome and investigating the relationship of joint alignment with respect to this.METHODS This longitudinal observational study assessed a total of 42 patients that had undergone UKA(n=23)and HTO(n=19)to treat medial compartment knee osteoarthritis.Patient-reported outcome measures(PROMs)were collected to evaluate clinical outcome.These included two disease-specific(Knee Injury and Osteoarthritis Outcome Score,Oxford Knee Score)and two generic(EQ-5D-5L,Short Form-12)PROMs.The radiographic parameters of knee alignment assessed were the:Hip-knee-ankle angle,mechanical axis deviation and angle of Mikulicz line.RESULTS Statistical analyses demonstrated significant(P<0.001),preoperative to postoperative,improvements in the PROM scores of both groups.There were,however,no significant inter-group differences in the postoperative PROM scores of the UKA and HTO group.Several significant correlations associated a more distolaterally angled Mikulicz line with worse knee function and overall health preoperatively(P<0.05).Postoperatively,two clusters of significant correlations were observed between the disease-specific PROM scores and knee joint alignment parameters(hip-knee-ankle angle,mechanical axis deviation)within the HTO group;yet no such associations were observed within the UKA group.CONCLUSION UKAs and HTOs are both efficacious operations that provide a comparable degree of clinical benefit to patients with medial compartment knee osteoarthritis.Clinical outcome has a limited association with radiographic parameters of knee joint alignment postoperatively;however,a more distolaterally angled Mikulicz line appears associated with worse knee function/health-related quality of life preoperatively. 展开更多
关键词 ARTHROPLASTY OSTEOTOMY Medial compartment OSTEOARTHRITIS Knee alignment Patient reported outcome measures
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Alignment Techniques in Total Knee Arthroplasty:Where do We Stand Today?
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作者 Hemanta Dhungana Subhash Jangid Meghal Goyal 《Chinese Medical Sciences Journal》 CAS CSCD 2024年第3期224-233,共10页
Achieving optimal alignment in total knee arthroplasty(TKA) is a critical factor in ensuring optimal outcomes and long-term implant survival. Traditionally, mechanical alignment has been favored to achieve neutral pos... Achieving optimal alignment in total knee arthroplasty(TKA) is a critical factor in ensuring optimal outcomes and long-term implant survival. Traditionally, mechanical alignment has been favored to achieve neutral postoperative joint alignment. However, contemporary approaches, such as kinematic alignments and hybrid techniques including adjusted mechanical, restricted kinematic, inverse kinematic, and functional alignments, are gaining attention for their ability to restore native joint kinematics and anatomical alignment, potentially leading to enhanced functional outcomes and greater patient satisfaction. The ongoing debate on optimal alignment strategies considers the following factors: long-term implant durability, functional improvement, and resolution of individual anatomical variations. Furthermore, advancements of computer-navigated and robotic-assisted surgery have augmented the precision in implant positioning and objective measurements of soft tissue balance. Despite ongoing debates on balancing implant longevity and functional outcomes, there is an increasing advocacy for personalized alignment strategies that are tailored to individual anatomical variations. This review evaluates the spectrum of various alignment techniques in TKA, including mechanical alignment, patient-specific kinematic approaches, and emerging hybrid methods. Each technique is scrutinized based on its fundamental principles, procedural techniques, inherent advantages, and potential limitations, while identifying significant clinical gaps that underscore the need for further investigation. 展开更多
关键词 total knee arthroplasty hybrid alignment functional alignment kinematic alignment alignment axes anatomical alignment mechanical alignment
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Joint alignment and steering to manage interference
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作者 Zhao Li Xiujuan Liang +2 位作者 Yinghou Liu Jia Liu Zheng Yan 《Digital Communications and Networks》 SCIE CSCD 2024年第2期429-438,共10页
In wireless communication networks,mobile users in overlapping areas may experience severe interference,therefore,designing effective Interference Management(IM)methods is crucial to improving network performance.Howe... In wireless communication networks,mobile users in overlapping areas may experience severe interference,therefore,designing effective Interference Management(IM)methods is crucial to improving network performance.However,when managing multiple disturbances from the same source,it may not be feasible to use existing IM methods such as Interference Alignment(IA)and Interference Steering(IS)exclusively.It is because with IA,the aligned interference becomes indistinguishable at its desired Receiver(Rx)under the cost constraint of Degrees-of-Freedom(DoF),while with IS,more transmit power will be consumed in the direct and repeated application of IS to each interference.To remedy these deficiencies,Interference Alignment Steering(IAS)is proposed by incorporating IA and IS and exploiting their advantages in IM.With IAS,the interfering Transmitter(Tx)first aligns one interference incurred by the transmission of one data stream to a one-dimensional subspace orthogonal to the desired transmission at the interfered Rx,and then the remaining interferences are treated as a whole and steered to the same subspace as the aligned interference.Moreover,two improved versions of IAS,i.e.,IAS with Full Adjustment at the Interfering Tx(IAS-FAIT)and Interference Steering and Alignment(ISA),are presented.The former considers the influence of IA on the interfering user-pair's performance.The orthogonality between the desired signals at the interfered Rx can be maintained by adjusting the spatial characteristics of all interferences and the aligned interference components,thus ensuring the Spectral Efficiency(SE)of the interfering communication pairs.Under ISA,the power cost for IS at the interfered Tx is minimized,hence improving SE performance of the interfered communication-pairs.Since the proposed methods are realized at the interfering and interfered Txs cooperatively,the expenses of IM are shared by both communication-pairs.Our in-depth simulation results show that joint use of IA and IS can effectively manage multiple disturbances from the same source and improve the system's SE. 展开更多
关键词 INTERFERENCE Interference management Interference alignment Interference steering Spectral efficiency
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A likely paleo-autotetraploidization event shaped the high conservation of Nyssaceae genome
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作者 Yishan Feng Zhenyi Wang +17 位作者 Qimeng Xiao Jia Teng Jianyu Wang Zijian Yu Jiaqi Wang Qiang Xu Yan Zhang Shaoqi Shen Shoutong Bao Yu Li Zimo Yan Yue Ding Zihan Liu Yuxian Li Tianyu Lei Min Yuan Xiu-Qing Li Jinpeng Wang 《Horticultural Plant Journal》 SCIE CAS CSCD 2024年第3期911-930,共20页
Scientific knowledge about the ancestral genome of core eudicot plant kingdom can potentially have profound impacts on both basic and applied research,including evolution,genetics,genomics,ecology,agriculture,forestry... Scientific knowledge about the ancestral genome of core eudicot plant kingdom can potentially have profound impacts on both basic and applied research,including evolution,genetics,genomics,ecology,agriculture,forestry,and global climate.To investigate which plant conserves best the core eudicots common ancestor genome,we compared Arcto-Tertiary relict Nyssaceae and 30 other eudicot plant families.The genomes of Davidia involucrata(a known living fossil),Camptotheca acuminata and Nyssa sinensis,one per existent genus of Nyssaceae,were performed comparative genomic analysis.We found that Nyssaceae originated from a single Nyssaceae common tetraploidization event(NCT)-autotetraploidization 28-31 Mya after the core eudicot common hexaploidization(ECH).We identified Nyssaceae orthologous and paralogous genes,determined its chromosomal evolutionary trajectory,and reconstructed the Nyssaceae most recent ancestor genome.D.involucrata genome contained the entire seven paleochromosomes and 17 ECH-generated eudicot common ancestor chromosomes and was the slowest in mutation among the analyzed 42 species of 31 plant families.Combing both its high retention of paleochromosomes and its low mutation rate,D.involucrata provides the best case in conservation of the core eudicot paleogenome. 展开更多
关键词 NYSSACEAE POLYPLOIDIZATION Multigenome alignment Evolutionary rate Autotetraploidization Karyotype evolution
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