检索结果-南通市图书馆

Degree elevation from Bzier curve to C-Bzier curve with corner cutting form

在线全文

学校读者我要写书评

暂无评论

Applied Mathematics(A Journal of Chinese Universities) 2016年第2期31卷 165-176页

作者： shen wan-qiang wang guo-zhao School of Science Jiangnan University Wuxi 214122 China Department of Mathematics Zhejiang University Hangzhou 310027 China State Key Lab of CAD & CG Zhejiang University Hangzhou 310027 China.

The existing results of curve degree elevation mainly focus on the degree of algebraic polynomials. The paper considers the elevation of degree of the trigonometric polynomial, from a Bezier curve on the algebraic polynomial space, to a C-Bezier curve on the algebraic and trigonometric polynomial space. The matrix of degree elevation is obtained by an operator presentation and a derivation pyramid. It possesses not a recursive presentation but a direct expression. The degree elevation process can also be represented as a corner cutting form.

关键词： Curve modeling Bezier curve C-Bezier curve Degree elevation Corner cutting.

Direction monotonicity for a rational Bézier curve

在线全文

学校读者我要写书评

暂无评论

Applied Mathematics(A Journal of Chinese Universities) 2016年第1期31卷 1-20页

作者： shen wan-qiang wang guo-zhao HUANG Fang School of Science Jiangnan University State Key Lab of CAD & CG Zhejiang University Department of Mathematics Zhejiang University

The monotonicity of a rational Bezier curve, usually related to an explicit function, is determined by the used coordinate system. However, the shape of the curve is independent of the coordinate system. To meet the affine invariant property, a kind of generalized mono- tonicity, called direction monotonicity, is introduced for rational Bezier curves. The direction monotonicity is applied to both planar and space curves and to both Cartesian and affine co- ordinate systems, and it includes the traditional monotonicity as a subcase. By means of it, proper affine coordinate systems may be chosen to make some rational Bezier curves monotonic. Direction monotonic interpolation may be realized for some of the traditionally nonmonotonic data as well.

关键词： rational Bezier curve monotonicity explicit function affine coordinate system interpolation.

Triangular domain extension of algebraic trigonometricB′ezier-like basis

在线全文

学校读者我要写书评

暂无评论

Applied Mathematics(A Journal of Chinese Universities) 2011年第2期26卷 151-160页

作者： WEI Yong-wei shen wan-qiang wang guo-zhao Department of Mathematics Zhejiang University Hangzhou 310027 China Department of Applied Mathematics Shanghai Maritime University Shanghai 201306 China

In computer aided geometric design （CAGD）, B′ezier-like bases receive more andmore considerations as new modeling tools in recent years. But those existing B′ezier-like basesare all defined over the rectangular domain. In this paper, we extend the algebraic trigono-metric B′ezier-like basis of order 4 to the triangular domain. The new basis functions definedover the triangular domain are proved to fulfill non-negativity, partition of unity, symmetry,boundary representation, linear independence and so on. We also prove some properties of thecorresponding B′ezier-like surfaces. Finally, some applications of the proposed basis are shown.

关键词： CAGD free form modeling blended space basis function triangular domain Bernstein basis.

Functional characterization of a potassium transporter gene NrHAK1 in Nicotiana rustica

在线全文

学校读者我要写书评

暂无评论

Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2008年第12期9卷 944-952页

作者： zhao-kui guo Qian YANG Xiu-qing wan Pei-qiang YAN Department of Life Sciences and Engineering Harbin Institute of Technology Harbin 150001 China Mudanjiang Tobacco Research Institute Mudanjiang 157011 China

The purpose of this study is to investigate the function of a novel potassium transporter gene (NrHAK1) isolated from Nicotiana rustica roots using yeast complement and real-time PCR technique. The complementary DNA (cDNA) of NrHAK1, 2 488 bp long, contains an open reading frame (ORF) of 2 334 bp encoding a protein of 777 amino acids (87.6 kDa) with 12 predicted transmembrane domains. The NrHAK1 protein shows a high sequence similarity to those of high-affinity potassium transporters in Mesembryanthemum, Phytolacca acinosa, Arabidopsis thaliana, and so on. We found that the NrHAK1 gene could complement the yeast-mutant defect in K+ uptake. Among several tissues surveyed, the expression level of NrHAK1 was most abundant in the root tip and was up-regulated when exposed to potassium starvation. Moreover, the transcript accumulation was significantly reduced by adding 5 mmol/L NH4+ to the solution. These results suggest that NrHAK1 plays an important role in potassium absorption in N. rustica.

关键词： Functional characterization K^+ transporter Nicotiana rustica

OStme: Online consensus survival analysis web server for tumor microenvironment components of pan-cancers

在线全文

学校读者我要写书评

暂无评论

Genes & Diseases 2023年第6期10卷 2256-2259页

作者： Longxiang Xie qiang wang Xiaoyu Ma guo zhao Zhongyi Yan Huimin Li wan Zhu Zhanjie Zuo Xiangqian guo Department of Preventive Medicine Institute of Biomedical InformaticsBioinformatics CenterHenan Provincial Engineering Center for Tumor Molecular MedicineAcademy for Advanced Interdisciplinary StudiesSchool of SoftwareSchool of Basic Medical SciencesHenan UniversityKaifengHenan 475004China Department of Anesthesia Stanford UniversityStanfordCA 94305United States Thoracic Cancer Treatment Center Armed Police Beijing Corps HospitalBeijing 100027China

Tumor microenvironment(TME)is the environment around the tumor cells,consisting of extracellular matrix,nonmalignant stromal cells,and various types of immune cells(like macrophages,B and T lymphocytes).1 TME has been recurrently reported to play important roles in the progression of cancers.1 The mechanism study of TME may offer opportunities for targeted/immune ***,how TME components impact the prognosis of cancer patients remains to be determined.

关键词： cancers microenvironment prognosis

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Ball基的推广

软件学报 2005年第11期16卷 1992-1999页

作者：沈莞蔷汪国昭浙江大学数学系浙江杭州310027

构造了一系列次数为n且带有参数k(2≤k≤■n2■+1)的新的广义Ball基,作为wang-Ball基(k=2)到Said-Ball基(k=■n2■+1)的过渡,并给出新基的一些性质.接着,由新基定义出新的广义Ball曲线,给出曲线的递归求值、升阶和降阶逼近算法.最后,提... 详细信息

构造了一系列次数为n且带有参数k(2≤k≤■n2■+1)的新的广义Ball基,作为wang-Ball基(k=2)到Said-Ball基(k=■n2■+1)的过渡,并给出新基的一些性质.接着,由新基定义出新的广义Ball曲线,给出曲线的递归求值、升阶和降阶逼近算法.最后,提出相应的三角基,并给出三角曲面的递归求值和升阶算法.

关键词： Ball基 Said—Ball基 wang—Ball基 Bernstein基 Bézier曲线

MRUNet:A two-stage segmentation model for small insect targets in complex environments

在线全文

学校读者我要写书评

暂无评论

Journal of Integrative Agriculture 2023年第4期22卷 1117-1130页

作者： wang Fu-kuan HUANG Yi-qi HUANG zhao-cheng shen Hao HUANG Cong QIAO Xi QIAN wan-qiang College of Mechanical Engineering Guangxi UniversityNanning 530004P.R.China Lingnan Guangdong Laboratory of Modern Agriculture Genome Analysis Laboratory of the Ministry of Agriculture and Rural AffairsAgricultural Genomics Institute at ShenzhenChinese Academy of Agricultural SciencesShenzhen 518120P.R.China Wuzhou Product Quality Inspection Institute Wuzhou 543000P.R.China

Online automated identification of farmland pests is an important auxiliary means of pest *** practical applications,the online insect identification system is often unable to locate and identify the target pest accurately due to factors such as small target size,high similarity between species and complex *** facilitate the identification of insect larvae,a two-stage segmentation method,MRUNet was proposed in this ***,MRUNet borrows the practice of object detection before semantic segmentation from Mask R-CNN and then uses an improved lightweight UNet to perform the semantic *** reliably evaluate the segmentation results of the models,statistical methods were introduced to measure the stability of the performance of the models among samples in addition to the evaluation indicators commonly used for semantic *** experimental results showed that this two-stage image segmentation strategy is effective in dealing with small targets in complex *** with existing state-of-the-art semantic segmentation methods,MRUNet shows better stability and detail processing ability under the same *** study provides a reliable reference for the automated identification of insect larvae.

关键词： insect larvae deep learning semantic segmentation object detection

Designing solid-state interfaces on lithium-metal anodes: a review

在线全文

学校读者我要写书评

暂无评论

Science China Chemistry 2019年第10期62卷 1286-1299页

作者： Chen-Zi zhao Hui Duan Jia-Qi Huang Juan Zhang qiang Zhang Yu-guo guo Li-Jun wan Beijing Key Laboratory of Green Chemical Reaction Engineering and Technology Department of Chemical EngineeringTsinghua UniversityBeijing 100084China CAS Key Laboratory of Molecular Nanostructure and Nanotechnology CAS Research/Education Center for Excellence in Molecular SciencesBeijing National Laboratory for Molecular SciencesInstitute of ChemistryChinese Academy of SciencesBeijing 100190China Advanced Research Institute of Multidisciplinary Science Beijing Institute of TechnologyBeijing 100081China University of Chinese Academy of Sciences Beijing 100049China

Li-metal anodes are one of the most promising energy storage systems that can considerably exceed the current technology to meet the ever-increasing demand of power applications. The apparent cycling performances and dendrite challenges of Li-metal anodes are highly influenced by the interface layer on the Li-metal anode because the intrinsic high reactivity of metallic Li results in an inevitable solid-state interface layer between the Li-metal and electrolytes. In this review, we summarize the recent progress on the interfacial chemistry regarding the interactions between electrolytes and ion migration through dynamic interfaces. The critical factors that affect the interface formation for constructing a stable interface with a low resistance are reviewed. Moreover, we review emerging strategies for rationally designing multiple-structured solid-state electrolytes and their interfaces, including the interfacial properties within hybrid electrolytes and the solid electrolyte/electrode interface. Finally, we present scientific issues and perspectives associated with Li-metal anode interfaces toward a practical Li-metal battery.

关键词： lithium-metal anode solid-state electrolyte energy chemistry rechargeable lithium-metal batteries solid electrolyte/electrode interface

Nanomotor-based H_(2)S donor with mitochondrial targeting function for treatment of Parkinson’s disease

在线全文

学校读者我要写书评

暂无评论

Bioactive Materials 2024年第1期31卷 578-589页

作者： Zinan zhao Lin Chen Chunhao Yang Wenyan guo Yali Huang Wenjing wang Mimi wan Chun Mao Jian shen National and Local Joint Engineering Research Center of Biomedical Functional Materials School of Chemistry and Materials ScienceNanjing Normal UniversityNanjing210023China

Reduction of endogenous hydrogen sulfide(H_(2)S)is considered to have an important impact on the progress of Parkinson’s disease(PD),thus exogenous H_(2)S supplementation is expected to become one of the key means to treat ***,at present,it is difficult for H_(2)S donors to effectively penetrate the blood brain barrier(BBB),selectively release H_(2)S in brain,and effectively target the mitochondria of neuron ***,we report a kind of nanomotor-based H_(2)S donor,which is obtained by free radical polymerization reaction between L-cysteine derivative modified-polyethylene glycol(PEG-Cys)and 2-methacryloyloxyethyl phosphorylcholine(MPC).This kind of H_(2)S donor can not only effectively break through BBB,but also be specifically catalyzed by cystathionineβ-synthase(CBS)in neurons of PD site in brain and 3-mercaptopyruvate sulfurtransferase(3-MST)in mitochondria to produce H_(2)S,endowing it with chemotaxis/motion ***,the unique chemotaxis effect of nanomotor can realize the purpose of precisely targeting brain and the mitochondria of damaged neuron cytopathic *** kind of nanomotor-based H_(2)S donor is expected to enrich the current types of H_(2)S donors and provide new ideas for the treatment of PD.

关键词： Hydrogen sulfide donor Mitochondrial targeting Parkinson’s disease Blood brain barrier