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Toolpath Interpolation and Smoothing for Computer Numerical Control Machining of Freeform Surfaces: A Review

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International Journal of Automation and computing 2020年第1期17卷 1-16页

作者： Wen-Bin Zhong Xi-Chun Luo Wen-Long Chang Yu-Kui Cai Fei Ding Hai-Tao Liu ya-zhou sun Centre for Precision Manufacturing Department of DesignManufacture&Engineering Management(DMEM)University of StrathclydeGlasgow G11XJUK Engineering and Physical Sciences Research Council(EPSRC)Future Metrology Hub Centre for Precision TechnologiesUniversity of HuddersfieldHuddersfield HD13DHUK School of Mechatronic Engineering Harbin Institute of TechnologyHarbin 150001China

Driven by the ever increasing demand in function integration,more and more next generation high value-added products,such as head-up displays,solar concentrators and intra-ocular-lens,etc.,are designed to possess freeform(i.e.,non-rotational symmetric)*** toolpath,composed of high density of short linear and circular segments,is generally used in computer numerical control(CNC)systems to machine those ***,the discontinuity between toolpath segments leads to high-frequency fluctuation of feedrate and acceleration,which will decrease the machining efficiency and product surface *** by the ever-increasing need for high-speed high-precision machining of those products,many novel toolpath interpolation and smoothing approaches have been proposed in both academia and industry,aiming to alleviate the issues caused by the conventional toolpath representation and interpolation *** paper provides a comprehensive review of the state-of-the-art toolpath interpolation and smoothing approaches with systematic *** advantages and disadvantages of these approaches are *** future research directions are also offered.

关键词： Computer numerical control(CNC) toolpath interpolation smoothing freeform surface

Temperature dependence of CsI:Tl coupled to a PIN photodiode and a silicon photomultiplier

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Nuclear Science and Techniques 2019年第2期30卷 81-89页

作者： Yu sun Zhi-Yu sun Yu-Hong Yu Ruo-Fu Chen Shu-Weng Tang Fang Fang Duo yan Qiang Hu Ke Yue Shi-Tao Wang Xue Heng Zhang Yong-Jie Zhang Jun-Lin Chen ya-zhou sun Ze-Hui Cheng Bi-Tao Hu Institute of Modern Physics Chinese Academy of Sciences Lanzhou University University of Chinese Academy of Sciences

With the aim of simulating the harsh temperature condition of space, a thallium-activated cesium iodide crystal(CsI:Tl) detector readout with a PIN photodiode(CsI:Tl(PD)) and with a silicon photomultiplier(CsI:Tl(SiPM)) is investigated over a temperature range from-40 to 40 ℃. With the increase in temperature, the output signal increases by ～ 24% with CsI:Tl(PD) and decreases by ～69% with CsI:Tl(SiPM). To reduce the effect of temperature in outer space, a method of bias voltage compensation is adopted for CsI:Tl(SiPM). Our study demonstrates that after correcting the temperature the variation in the analog-to-digital converter's amplitude is< 3%.

关键词： CsI:Tl SiPM PD Temperature dependence Correction method

Isotopic production cross sections of fragmentation residues produced by ^(18)O ions on a carbon target near 260 MeV/nucleon

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Chinese Physics C 2022年第11期46卷 1-6页

作者： Xiao-Dong Xu ya-zhou sun Shi-Tao Wang Bo Mei Shu-ya Jin Xue-Heng Zhang Zhi-Yu sun Yi-Xuan Zhao Shu-Wen Tang Yu-Hong Yu Duo yan Fang Fang Yong-Jie Zhang Shao-Bo Ma CAS Key Laboratory of High Precision Nuclear Spectroscopy Institute of Modern PhysicsChinese Academy of SciencesLanzhou 730000China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100049China Sino-French Institute of Nuclear Engineering and Technology Sun Yat-sen UniversityZhuhai 519082China School of Nuclear Science and Technology Lanzhou UniversityLanzhou 730000China

The isotopic cross sections of residual nuclei produced in fragmentation reactions of ^(18)O projectiles impinging on a carbon target at energies near 260 MeV/nucleon were measured at the HIRFL facility in Lanzhou(China).A full identification of atomic and mass numbers of fragments was achieved from the determination of their magnetic rigidity,energy loss,and time of *** production cross sections for a dozen of nitrogen,carbon,and boron isotopes were determined with uncertainties below 30% for most of the *** obtained cross sections for N and B isotopes show a rather good agreement with previous experimental data obtained with different projectile *** cross sections for some C isotopes seem to exhibit a dependence on the projectile energy.A comparison of the data and several theoretical model calculations are presented.

关键词： heavy-ion collisions projectile fragmentation isotopic production cross sections

Microstructure and Wear/corrosion Resistance of Stainless Steel Laser-alloyed with Mn+W_(2)C, Mn+NiWC and Mn+SiC

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 283-294页

作者： zhou Rui DIAO Xiaogang sun Yixin School of Metallurgical Engineering Jiangsu University of Science and TechnologyZhangjiagang 215600China CITIC Heavy Cast Iron Industry Co. Ltd.Luoyang 417039China

In-situ formed high Mn steel coating reinforced by carbides was formed by laser surface alloying(LSA).Laser alloyed layers on 1Cr18Ni9Ti steel with Mn+W_(2)C(specimen A),Mn+NiWC(specimen B)and Mn+SiC(specimen C)powders were fabricated to improve the wear and corrosion behavior of 1Cr18Ni9Ti steel blades in high speed *** evolution,phases,element distribution,microhardness,wear and corrosion behavior of the laser alloyed layers were *** indicated that high Mn steel matrix composites with undissolved W_(2)C,WC and other in-situ formed carbides were formed by LSA with Mn+W_(2)C and Mn+NiWC while SiC totally dissolved into the high Mn matrix when adding Mn+*** as the binding phase in Ni-WC powder decreased the crack sensitivity of the alloyed layer as compared with the addition of W_(2)C *** improvement in average microhardness was achieved in the matrix in specimen A,B and C,with the value of 615,602 and 277 HV_(0.5),while that of the substrate was 212 HV_(0.5).The increase of microhardness,wear and corrosion resistance is highly corelated to microstructure,formed phases,type and content of carbides,micro-hardness and toughness of the alloyed layers.

关键词： laser surface alloying stainless steel carbide type microstructure wear and corrosion resistance

Fragmentation of stable and neutron-rich ^(12-16)C into boron fragments at approximately 240 MeV/nucleon

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Chinese Physics C 2022年第1期46卷 118-123页

作者： Shu-ya Jin ya-zhou sun Shi-Tao Wang Zhi-Yu sun Xue-Heng Zhang Zhi-Qiang Chen Bo Mei Yi-Xuan Zhao Shu-Wen Tang Yu-Hong Yu Duo yan Fang Fang Yong-Jie Zhang Shao-bo Ma Xiang-Man Liu Rui Han CAS Key Laboratory of High Precision Nuclear Spectroscopy Institute of Modern PhysicsChinese Academy of SciencesLanzhou 730000China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100080China School of Nuclear Science and Technology Lanzhou UniversityLanzhou 730000China School of Physics and Electrical Engineering Anyang Normal UniversityAnyang 455000China Sino-French Institute of Nuclear Engineering and Technology Sun Yat-sen UniversityZhuhai 519082China

The elemental fragmentation cross sections of boron fragments produced by stable and neutron-rich^(12-16)C beams with a carbon target were systematically measured at an incident beam energy of approximately 240 MeV/*** measured cross sections were found to increase as the projectile mass number *** observed feature is explained qualitatively based on the abrasion-ablation two-stage reaction model and is compared quantitatively with predictions from various reaction models,including empirical and statistical *** models agree with the measured cross sections within a factor of 2.

关键词： elemental fragmentation cross sections neutron-rich carbon isotopes abrasion-ablation model

Malicious Document Detection Based on GGE Visualization

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Computers, Materials & Continua 2025年第1期82卷 1233-1254页

作者： Youhe Wang Yi sun Yujie Li Chuanqi zhou Henan Province Key Laboratory of Information Security Information Engineering UniversityZhengzhou450000China

With the development of anti-virus technology,malicious documents have gradually become the main pathway of Advanced Persistent Threat(APT)attacks,therefore,the development of effective malicious document classifiers has become particularly ***,detection methods based on document structure and behavioral features encounter challenges in feature engineering,these methods not only have limited accuracy,but also consume large resources,and usually can only detect documents in specific formats,which lacks versatility and *** address such problems,this paper proposes a novel malicious document detection method-visualizing documents as GGE images(Grayscale,Grayscale matrix,Entropy).The GGE method visualizes the original byte sequence of the malicious document as a grayscale image,the information entropy sequence of the document as an entropy image,and at the same time,the grayscale level co-occurrence matrix and the texture and spatial information stored in it are converted into grayscale matrix image,and fuses the three types of images to get the GGE color *** Convolutional Block Attention Module-EfficientNet-B0(CBAM-EfficientNet-B0)model is then used for classification,combining transfer learning and applying the pre-trained model on the ImageNet dataset to the feature extraction process of GGE *** shown in the experimental results,the GGE method has superior performance compared with other methods,which is suitable for detecting malicious documents in different formats,and achieves an accuracy of 99.44%and 97.39%on Portable Document Format(PDF)and office datasets,respectively,and consumes less time during the detection process,which can be effectively applied to the task of detecting malicious documents in real-time.

关键词： Malicious document visualization EfficientNet-B0 convolutional block attention module GGE image

Efficient OpenMP Based Z-curve Encoding and Decoding Algorithms

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Computers, Materials & Continua 2025年第1期82卷 1313-1327页

作者： Zicheng zhou Shaowen sun Teng Liang Mengjuan Li Fengling Xia School of Electronic Science and Engineering University of Electronic Science and Technology of ChinaChengdu611731China Faculty of Information Engineering and Automation Kunming University of Science and TechnologyKunming650500China School of Communications Information Engineering Yunnan Communications Vocational and Technical CollegeKunming650500China Library Yunnan Normal UniversityKunming650500China Faculty of Civil Aviation and Aeronautics Kunming University of Science and TechnologyKunming650500China

Z-curve’s encoding and decoding algorithms are primely important in many Z-curve-based *** bit interleaving algorithm is the current state-of-the-art algorithm for encoding and decoding *** simple,its efficiency is hindered by the step-by-step coordinate shifting and bitwise *** tackle this problem,we first propose the efficient encoding algorithm LTFe and the corresponding decoding algorithm LTFd,which adopt two optimization methods to boost the algorithm’s efficiency:1)we design efficient lookup tables(LT)that convert encoding and decoding operations into table-lookup operations;2)we design a bit detection mechanism that skips partial order of a coordinate or a Z-value with consecutive 0s in the front,avoiding unnecessary iterative *** propose order-parallel and point-parallel OpenMP-based algorithms to exploit the modern multi-core *** results on discrete,skewed,and real datasets indicate that our point-parallel algorithms can be up to 12.6×faster than the existing algorithms.

关键词： Z-curve lookup table OpenMP bit detection mechanism

Text-Image Feature Fine-Grained Learning for Joint Multimodal Aspect-Based Sentiment Analysis

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Computers, Materials & Continua 2025年第1期82卷 279-305页

作者： Tianzhi Zhang Gang zhou Shuang Zhang Shunhang Li Yepeng sun Qiankun Pi Shuo Liu School of Data and Target Engineering Information Engineering UniversityZhengzhou450001China Information Engineering Department Liaoning Provincial College of CommunicationsShenyang110122China School of Computer and Artificial Intelligence Zhengzhou UniversityZhengzhou450000China

Joint Multimodal Aspect-based Sentiment Analysis(JMASA)is a significant task in the research of multimodal fine-grained sentiment analysis,which combines two subtasks:Multimodal Aspect Term Extraction(MATE)and Multimodal Aspect-oriented Sentiment Classification(MASC).Currently,most existing models for JMASA only perform text and image feature encoding from a basic level,but often neglect the in-depth analysis of unimodal intrinsic features,which may lead to the low accuracy of aspect term extraction and the poor ability of sentiment prediction due to the insufficient learning of intra-modal *** this problem,we propose a Text-Image Feature Fine-grained Learning(TIFFL)model for ***,we construct an enhanced adjacency matrix of word dependencies and adopt graph convolutional network to learn the syntactic structure features for text,which addresses the context interference problem of identifying different aspect ***,the adjective-noun pairs extracted from image are introduced to enable the semantic representation of visual features more intuitive,which addresses the ambiguous semantic extraction problem during image feature ***,the model performance of aspect term extraction and sentiment polarity prediction can be further optimized and *** on two Twitter benchmark datasets demonstrate that TIFFL achieves competitive results for JMASA,MATE and MASC,thus validating the effectiveness of our proposed methods.

关键词： Multimodal sentiment analysis aspect-based sentiment analysis feature fine-grained learning graph convolutional network adjective-noun pairs

A matrix metalloproteinase-responsive hydrogel system controls angiogenic peptide release for repair of cerebral ischemia/reperfusion injury

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Neural Regeneration Research 2025年第2期20卷 503-517页

作者： Qi Liu Jianye Xie Runxue zhou Jin Deng Weihong Nie Shuwei sun Haiping Wang Chunying Shi Department of Human Anatomy Histology and EmbryologySchool of Basic MedicineQingdao UniversityQingdaoShandong ProvinceChina Department of Neurology The Affiliated Hospital of Qingdao UniversityQingdaoShandong ProvinceChina Department of General Practice The Affiliated Hospital of Qingdao UniversityQingdaoShandong ProvinceChina

Vascular endothelial growth factor and its mimic peptide KLTWQELYQLKYKGI(QK)are widely used as the most potent angiogenic factors for the treatment of multiple ischemic ***,conventional topical drug delivery often results in a burst release of the drug,leading to transient retention(inefficacy)and undesirable diffusion(toxicity)in ***,a drug delivery system that responds to changes in the microenvironment of tissue regeneration and controls vascular endothelial growth factor release is crucial to improve the treatment of ischemic *** metalloproteinase-2(MMP-2)is gradually upregulated after cerebral ***,vascular endothelial growth factor mimic peptide QK was self-assembled with MMP-2-cleaved peptide PLGLAG(TIMP)and customizable peptide amphiphilic(PA)molecules to construct nanofiber hydrogel ***-TIMP-QK was found to control the delivery of QK by MMP-2 upregulation after cerebral ischemia/reperfusion and had a similar biological activity with vascular endothelial growth factor in *** results indicated that PA-TIMP-QK promoted neuronal survival,restored local blood circulation,reduced blood-brain barrier permeability,and restored motor *** findings suggest that the self-assembling nanofiber hydrogel PA-TIMP-QK may provide an intelligent drug delivery system that responds to the microenvironment and promotes regeneration and repair after cerebral ischemia/reperfusion injury.

关键词： angiogenesis biomaterial blood-brain barrier cerebral ischemia/reperfusion injury control release drug delivery inflammation QK peptides matrix metalloproteinase-2 neuroprotection self-assembling nanofiber hydrogel