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An efficient algorithm for approximate Voronoi diagram construction on triangulated surfaces

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Computational Visual Media 2023年第3期9卷 443-459页

作者： Wenlong Meng Pengbo Bo Xiaodong zhang jixiang Hong Shiqing Xin Changhe Tu School of Computer Science and Technology Harbin Institute of TechnologyWeihai 264209China School of Computer Science and Technology Shandong UniversityQingdao 266237China

Voronoi diagrams on triangulated surfaces based on the geodesic metric play a key role in many applications of computer graphics.Previous methods of constructing such Voronoi diagrams generally depended on having an exact geodesic metric.However,exact geodesic computation is time-consuming and has high memory usage,limiting wider application of geodesic Voronoi diagrams(GVDs).In order to overcome this issue,instead of using exact methods,we reformulate a graph method based on Steiner point insertion,as an effective way to obtain geodesic distances.Further,since a bisector comprises hyperbolic and line segments,we utilize Apollonius diagrams to encode complicated structures,enabling Voronoi diagrams to encode a medial-axis surface for a dense set of boundary samples.Based on these strategies,we present an approximation algorithm for efficient Voronoi diagram construction on triangulated surfaces.We also suggest a measure for evaluating similarity of our results to the exact GVD.Although our GVD results are constructed using approximate geodesic distances,we can get GVD results similar to exact results by inserting Steiner points on triangle edges.Experimental results on many 3D models indicate the improved speed and memory requirements compared to previous leading methods.

关键词： geodesic Voronoi diagrams(GVDs) triangular surfaces mesh surfaces approximate geodesics Apollonius diagrams

A novel high-strength Al-La-Mg-Mn alloy for selective laser melting

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Journal of Materials Science & Technology 2023年第6期137卷 205-214页

作者： Xinkui zhang Liejun Li Zhi Wang Hanlin Peng jixiang Gao Zhengwu Peng Guangdong Key Laboratory for Advanced Metallic Materials Processing South China University of TechnologyGuangzhou 510640China Guangdong Provincial Key Laboratory of Advanced Welding Technology China-Ukraine Belt and Road Joint Laboratory on Materials Joining and Advanced ManufacturingChina-Ukraine Institute of WeldingGuangdong Academy of SciencesGuangzhou 510650China Guangdong Polytechnic Normal University Guangzhou 510635China

Developing high-strength Al-(La,Ce)alloys for additive manufacturing(AM)would entail considerable economic benefits.In this work,a novel near-eutectic Al-La alloy containing 5.50 wt.%Mg and 0.60 wt.%Mn was designed and fabricated via selective laser melting(SLM).Submicron Al_(11)La_(3)intermetallics with 3D continuous cellular-dendritic and granular morphologies were observed at the interior and boundary of the melt pool,respectively.Interestingly,these intermetallics are hierarchical and contained numerous Al_(6)Mn and Mg_(2)Si secondary nanoprecipitates.The as-fabricated alloy exhibited a tensile yield strength(YS)of 334 MPa and ultimate tensile strength(UTS)of 588 MPa at room temperature,which is the high-est UTS reported for Al-(La,Ce)alloys with an appreciable failure strain of∼6.4%.The 3D continuous cellular dendritic intermetallic and high Mg content afford significant strengthening and work harden-ing ability.In addition,the hierarchical feature of the intermetallics generated additional microcracks to coordinate the deformation.

关键词： Selective laser melting Al-La alloys 3D continuous structure Hierarchical precipitate High strength

Chemical screening reveals Ronidazole is a superior prodrug to Metronidazole for nitroreductase-induced cell ablation system in zebrafish larvae

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Journal of Genetics and Genomics 2021年第12期48卷 1081-1090页

作者： Siting Lai Ankita Kumari jixiang Liu Yiyue zhang Wenqing zhang Kuangyu Yen Jin Xu Department of Developmental Biology School of Basic Medical SciencesSouthern Medical UniversityGuangzhou 510515China Division of Cell Developmental and Integrative BiologySchool of MedicineSouth China University of TechnologyGuangzhou 510006China

The Metronidazole(MTZ)/nitroreductase(NTR)-mediated cell ablation system is the most commonly used chemical-genetic cell ablation method in zebrafish. This system can specifically ablate target cells under spatial and temporal control. The MTZ/NTR system has become a widely used cell ablation system in biological, developmental, and functional studies. However, the inadequate cell-ablation ability of some cell types and the side effects of high concentration MTZ impede extensive applications of the MTZ/NTR system. In the present study, the US drug collection library was searched to extend the NTR system. Six MTZ analogs were found, and the cell-ablation ability of these analogs was tested in zebrafish larvae. The results revealed that two of the NTR substrates, Furazolidone and Ronidazole, ablated target cells more efficiently than MTZ at lower concentrations. Furthermore, the working concentration of Ronidazole, but not Furazolidone and MTZ, did not affect axonal bridge formation during spinal cord regeneration. Our results,taken together, indicate that Ronidazole is a superior prodrug to MTZ for the NTR system, especially for the study of neuron regeneration in zebrafish larvae.

关键词： MTZ Ronidazole NTR Cell ablation Regeneration Zebrafish

Single molecule magnetic behavior and photo-enhanced proton conductivity in a series of photochromic complexes

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Chinese Chemical Letters 2022年第3期33卷 1417-1421页

作者： Qian zhang jixiang Hu Qi Li Dongxue Feng Zhenni Gao Guoming Wang College of Chemistry and Chemical Engineering Qingdao UniversityQingdao 266071China

Molecules with multifunctional properties are of immense interest in hybrid materials, while challenges still existed because of the limited compatibility of multiple functionalities in a single system. In this work, a series of metal-organic complexes were synthesized and characterized under the assembly of electron donor phosphonate, electron acceptor polypyridine ligand and spin carrier rare earth ions. All the compounds exhibited remarkable and reversible responses with photochromism and photomodulated fluorescence, originated from photogenerated radicals via electron transfer from phosphonates to polypyridine ligands. For the Dy analog, slow magnetic relaxation was observed at cryogenic temperature, indicating the single-molecule magnetic behavior. Furthermore, photogenerated radicals could enhance the proton conductive behavior, with about 2 times larger in magnitude after light irradiation for Dy and Y compounds. The introduction of photoluminescence, magnetism and proton conduction into metallic phosphonates can provide potential applications for photochromic materials.

关键词： Multifunctional Electron transfer Photochromism Single molecule magnetic behavior Proton conductivity

YOLOV5s object detection based on Sim SPPF hybrid pooling

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Optoelectronics Letters 2024年第6期20卷 367-371页

作者： DONG Xiuhuan LI Shixin zhang jixiang Tianjin University of Technology and Education Electronic Engineering Department

Aiming at the problem of low surface defect detection accuracy of industrial products, an object detection method based on simplified spatial pyramid pooling fast(Sim SPPF) hybrid pooling improved you only look once version 5s(YOLOV5s) model is proposed. The algorithm introduces channel attention(CA) module, simplified SPPF feature vector pyramid and efficient intersection over union(EIOU) loss function. Feature vector pyramids fuse high-dimensional and low-dimensional features, which makes semantic information richer. The CA mechanism performs maximum pooling and average pooling operations on the feature map. Hybrid pooling comprehensively improves detection computing efficiency and accurate deployment ability. The results show that the improved YOLOV5s model is better than the original YOLOV5s model. The average test accuracy(mAP) can reach 91.8%, which can be increased by 17.4%, and the detection speed can reach 108 FPS, which can be increased by 18 FPS. The improved model is practicable, and the overall performance is better than other conventional models.

关键词： A

Thermal Inertia of 330 MW Circulating Fluidized Bed Boiler during Load Change

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热科学学报:英文版 2023年第5期32卷 1771-1783页

作者： SUN Guorui WU Haowen LIU Shangzhong LIU Tonghua LIU jixiang YANG Hairui zhang Man Key Laboratory for Thermal Science and Power Engineering of Ministry of Education Department of Energy and Power EngineeringTsinghua UniversityBeijing 100084China Wuhan Yongping Science and Technology Co.Ltd. Wuhan 430000China

The operating principles of Circulating Fluidized Bed(CFB)boilers involve a significant amount of heat accumulation,which forms the thermal inertia of the boiler and hinders the improvement of its variable load response rate.This study aims to characterize the thermal inertia of CFB boilers by evaluating the change in the boiler's heat accumulation corresponding to the change in unit power generation.The thermal inertia of a 330MW CFB boiler was determined through the collection of operating data under four different operating conditions of 30%,50%,75%,and 100%load.The study proposes to substitute the existing refractory material with a metal grille to reduce the thermal inertia of the boiler.The effect of the metal grille on heat transfer was confirmed through verification on a 440 t/h CFB boiler,and its performance change and thermal inertia reduction were further predicted.The results indicate that over 50%of the total thermal inertia of CFB boilers originates from the refractory material.The use of metal grille in place of refractory material improved heat transfer in the furnace,resulting in a decrease of the furnace chamber temperature by 13℃in the 330 MW CFB boiler.This reduction of thermal inertia by 30%-35%will facilitate faster load lifting and lowering of the boiler,fulfilling the requirement for flexible peaking.

关键词： CFB boiler refractory thermal inertia heat accumulation

Prevalence and Correlates of Healthy Aging Among Elderly Aged 65 Years and Over-6 PLADs,China,2019

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China CDC weekly 2021年第4期3卷 69-73页

作者： Zhaoxue Yin Xin Gao Xiaochang zhang Xiang Si Xiaolei Zhu jixiang Ma Division of non-communicable diseases and elderly health management Chinese Center for Disease Control and PreventionBeijingChina Shandong Center for Disease Control and Prevention JinanShandongChina

What is already known on this topic?Healthy aging among Chinese older people has low prevalence.Some sociodemographic and lifestyle factors were shown to be associated with healthy aging.What is added by this report?The age-adjusted prevalence of healthy aging in the 6 provincial-level administrative divisions(PLADs)of China is 15.8%in 2019.County-level factors,such as the prevalence of healthy communities in a county,as well as some sociodemographic variables and physical exercise,are potential factors of healthy aging.What are the implications for public health practice?These findings showed that more targeted actions,including generalizing healthy communities and individual-level interventions,may be of great importance for healthy aging.

关键词： aging Healthy administrative

Comorbidities and high in-hospital mortality of cancer-associated pulmonary embolism:findings from a real-world registry study

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Chinese Medical Journal 2023年第16期136卷 2005-2007页

作者： jixiang Liu Feiya Xu Zhu zhang Yu zhang Kaiyuan Zhen Jieping Lei Dingyi Wang Peiran Yang Zhenguo Zhai Department of Pulmonary and Critical Care Medicine China-Japan Friendship HospitalBeijing 100029China Capital Medical University Beijing 100069China Department of Clinical Research and Data Management China-Japan Friendship HospitalBeijing 100029China Department of Physiology State Key Laboratory of Medical Molecular BiologyInstitute of Basic Medical SciencesChinese Academy of Medical SciencesSchool of Basic MedicinePeking Union Medical CollegeBeijing 100730China Graduate School of Peking Union Medical College Chinese Academy of Medical SciencesBeijing 100730China

To the Editor:Cancer has been recognized as an independent predisposing factor of venous thromboembolism(VTE),including pulmonary embolism(PE)and deep vein thrombosis(DVT).Patients with cancer have a sevenfold increased risk of VTE compared with those without cancer.[1]Evidence from autopsy in cancer patients showed that PE is an important disease complication in patients with cancer.[2]Optimal management of PE patients with cancer has become a major concern that challenges clinicians in daily clinical practice.Understanding the risk factors of all-cause death in PE patients with cancer in the real world may enable optimal management and improve their survival.Therefore,this study was performed to characterize cancerassociated PE and evaluate the clinical predictors of inhospital death based on the data of PE patient population in China.

关键词： embolism cancer clinical

Influence and mechanism of N-(3-oxooxtanoyl)-L-homoserine lactone(C_8-oxo-HSL) on biofilm behaviors at early stage

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Journal of Environmental Sciences 2012年第12期24卷 2035-2040页

作者： Siqing Xia Lijie Zhou Zhiqiang zhang jixiang Li State Key Laboratory of Pollution Control and Resource Reuse Tongji UniversityShanghai 200092China Sustainable Technology Research Center Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201210China

N-acyl-homoserines quenching, enzymatic quenching of bacterial quorum sensing, has recently applied to mitigate biofilm in membrane bioreactor. However, the effect of AHLs on the behavior of biofilm formation is still sparse. In this study, Pseudomonas aeruginosa biofilm was formed on ultra-filtration membrane under a series of N-（3-0xooxtanoyl）-L-homoserine lactone （C8-0xo-HSL） concentrations. Diffusing Cs-oxo-HSL increased the growth rate of cells on biofilm where the concentration of Cs-oxo-HSL was over 10-7 g/L. The C8-0xo-HSL gradient had no observable influence on cell density and extracellular polymeric substances of biofilm with over 10-7 g/L Cs-oxo-HSL. Surprisingly, 10-11-10-8 g/L of Cs-Oxo-HSL had no effect on cell growth in liquid culture. The cell analysis demonstrated that the quorum sensing system might enhance the growth of neighboring cells in contact with surfaces into biofilm and may influence the structure and organization of biofilm.

关键词： quorum sensing C8-oxo-HSL biofilm formation ultra-filtration membrane cell density extracellular polymericsubstances