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Flower solid modeling based on sketches

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第4期9卷 481-488页

作者： Zhan ding Shu-chang XU Xiu-zi YE Yin ZHANG San-yuan ZHANG State Key Lab of CAD ＆ CG School of Computer Science Zhejiang University Hangzhou 310027 China

In this paper we propose a method to model flowers of solid shape. Based on (Ijiri et al., 2005)’s method, we separate individual flower modeling and inflorescence modeling procedures into structure and geometry modeling. We incorporate interactive editing gestures to allow the user to edit structure parameters freely onto structure diagram. Furthermore, we use free-hand sketching techniques to allow users to create and edit 3D geometrical elements freely and easily. The final step is to automatically merge all independent 3D geometrical elements into a single waterproof mesh. Our experiments show that this solid modeling approach is promising. Using our approach, novice users can create vivid flower models easily and freely. The generated flower model is waterproof. It can have applications in visualization, animation, gaming, and toys and decorations if printed out on 3D rapid prototyping devices.

关键词： Solid modeling Floral diagram Inflorescence Gesture Constrained Delauny triangulation (CDT) Freehand sketching

Study on influence of key blasthole parameters on tunnel overbreak

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Underground Space 2023年第2期9卷 76-90页

作者： zi-qiang Li Zheng Li Wei-wei Huang Xuan-ming ding Hang Zhang School of Civil Engineering and Architecture Chongqing University of Science&TechnologyChongqing 401331China Key Laboratory of New Technology for Construction of Cities in Mountain Area Ministry of EducationChongqing UniversityChongqing 400045China Chongqing City Construction Investment(Group)Co. Ltd.Chongqing 400023China School of Civil Engineering Chongqing University400045China

To determine the influence of key blasthole parameters on tunnel overbreak during blasting construction,an intelligent detection sys-tem for tunnel blasting construction is independently *** the key blasthole parameters and overbreak of a typical section of a single line tunnel under the condition of Class V surrounding rock are analyzed and *** actual data obtained is compared with the results of numerical simulations and theoretical *** results are as follows:(1)Quantitative analysis is performed based on the blasthole angle,opening position,and charge mass by the self-developed intelligent detection equipment for blasthole parameters,which can be used to guide the drilling *** scanning equipment for outline excavation can be used to image the actual excavation section in real-time and has the advantages of high precision and fast speed;(2)Tunnel overbreak can be regarded as consisting of two parts:the surrounding rock damage caused by the blasting load,and the collapse of the surrounding rock caused by the blasthole opening *** parameter of the peripheral hole will affect the tunnel overbreak;however,the key parameter is the blasthole opening position;(3)The distributions of the tunnel overbreak volume obtained with the theoretical analysis,finite element simulation,and measurements are basically *** the condition of Class V surrounding rock,the overbreak of this single line tunnel can reach 14.1–78.2 *** meet the specification requirements,the opening position and construction accuracy of the peripheral hole should be strictly controlled.

关键词： Tunnel blasting Blasthole parameters Tunnel overbreak Surrounding rock damage Smooth surface blasting

Metal-organic frameworks derived transition metal phosphides for electrocatalytic water splitting

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Journal of Energy Chemistry 2022年第5期31卷 494-520页

作者： Li-Ming Cao Jia Zhang Li-Wen ding zi-Yi Du Chun-Ting He Key Laboratory of Functional Small Molecules for Ministry of Education College of Chemistry and Chemical EngineeringJiangxi Normal UniversityNanchang 330022JiangxiChina Key Laboratory for Green Chemistry of Jiangxi Province Nanchang 330022JiangxiChina

It is critical to synthesize high-efficiency electrocatalysts to boost the performance of water splitting to meet the requirements of industrial applications. Metal-organic frameworks(MOFs) can function as ideal molecular platforms for the design of highly reactive transition metal phosphides(TMPs), a kind of candidates for high-efficiently electrocatalytic water splitting. The intrinsic activity of the electrocatalysts can be greatly improved via modulating the electronic structure of the catalytic center through the MOF precursors/templates. Moreover, the carbon layer converted in-situ by the organic ligands can not only protect the TMPs from being degraded in the harsh electrochemical environments, but also avoid agglomeration of the catalysts, thereby promoting their activities and stabilities. Furthermore,heteroatom-containing ligands can incorporate N, S or P, etc. atoms into the carbon matrixes after conversion, regulating the coordination microenvironments of the active centers as well as their electronic structures. In this review, we first summarized the latest developments in MOF-derived TMPs by the unique advantages in metal, organic ligand, and morphology regulations for electrocatalytic water splitting. Secondly, we concluded the critical scientific issues currently facing for designing state-of-the-art TMP-based electrocatalysts. Finally, we presented an outlook on this research area, encompassing electrocatalyst construction, catalytic mechanism research, etc.

关键词： Metal-organic framework Transition metal phosphide Water splitting Electrocatalyst Electronic structure

Characteristic Mode Analysis for Thin Dielectric Sheets with Alternative Surface Integral Equation

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Chinese Journal of Electronics 2022年第6期31卷 1181-1188页

作者： JIA Chunlai HE zi ding Dazhi GUAN Ling AI Xia LIU Jiaqi CHEN Xuewen Department of Communication Engineering Nanjing University of Science and Technology Science and Technology on Electromagnetic Scattering Laboratory Beijing Institute of Environmental Features National Key Laboratory of Science and Technology on Test Physics and Numerical Mathematics School of Physics and Wuhan National Laboratory for Optoelectronics Huazhong University of Science and Technology

When the dielectric sheet is electrically thin in the normal direction, the conventional volume integral equation(VIE) can be approximately simplified to the surface one. On this basis, a novel surface integral equation-based formulation is presented for analyzing characteristic mode(CM) of thin dielectric sheets. The resultant CMs are expressed with tangential and normal components of electric volume currents, which are more intuitive than the conventional VIE-based one. Due to the application of volume equivalence principle, the proposed formulation is immune to non-physical modes. The CMs of typical thin dielectric bodies, including the dielectric substrate and radome, are analyzed to show that the proposed formulation is computationally efficient with encouraging accuracy.

关键词： normal components alternative surface integral equation thin dielectric sheets normal direction electric volume currents dielectric sheet radome radomes dielectric bodies surface integral equation-based formulation volume equivalence principle thin dielectric bodies tangential components nonphysical modes electromagnetic wave scattering conventional volume integral equation integral equations characteristic mode analysis dielectric substrate

Susceptibility breakpoint for cefquinome against Escherichia coli and Staphylococcus aureus from pigs

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Journal of Integrative Agriculture 2021年第7期20卷 1921-1932页

作者： ZHANG Hui-lin ZHAO Yi-yang ZHOU zi-chong ding Huan-zhong Guangdong Key Laboratory for Veterinary Drug Development and Safety Evaluation South China Agricultural UniversityGuangzhou 510000P.R.China

Cefquinome is the only fourth-generation cephalosporin used solely for veterinary *** this study,we established the wild-type cut-off(CO_(WT))and pharmacokinetic/pharmacodynamic cut-off(CO_(PD))of cefquinome against Escherichia coli and Staphylococcus aureus.A total of 210 *** and 160 *** isolates were collected from pigs in Guangdong Province between 2014 and *** minimum inhibitory concentrations(MICs)were determined using a microdilution broth ***_(50)and MIC_(90)were 0.06 and 0.25μg m L^(–1)for *** and 0.5 and 1μg m L^(–1)for ***,*** analysis and the ECOFFinder Program showed that the CO_(WT)for cefquinome against *** and *** were0.125 and 2μg m L^(–1),*** resistance rates were 11.9%for *** and 6.25%for *** on a5000-subject Monte Carlo simulation,the CO_(PD)value for cefquinome against *** and *** was 0.25μg m L^(–1)under the recommended dose(2 mg kg^(–1),twice a day for 3 days),confirming that infections caused by strains with MIC≤0.25μg m L^(–1)could be effectively *** adjustment of the dosing regimen to 4.5 mg kg^(–1),effective treatment(>90)was achieved for *** infections with MIC_(90)1μg m L^(–1).This susceptibility breakpoint determination is significant for resistant surveillance and cefquinome dosage guidance against *** and *** in pigs.

关键词： cefquinome Escherichia coli Staphylococcus aureus CO_(WT) CO_(PD)

Fast Computation of Electrostatic Interactions for a Charged Polymer with Applied Field

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Chinese Journal of Polymer Science 2020年第6期38卷 665-672页

作者： Hao Lin zi-Tong Lei Ming-Ming ding Hong-Jun Wang Tong-Fei Shi School of Mathematics Jilin Normal UniversityChangchun 130103China State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 730022China College of Computer Jilin Normal UniversitySi ping 136000China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei230026China

Using a hybrid simulation approach that combines a finite difference method with a Brownian dynamics,we investigated the motion of charged *** to the fact that polymer-solution systems often contain a large number of particles and the charged palymer chains are in a state of random motion,it is a time consuming task to calculate the electrostatic interaction of the ***,we propose a new strategy to shorten the CPU time by reducing the iteration *** simulation results ilustrate the effect of preset parameters on CPU time and accuracy,and demonstrate the feasibility of the"local iteration"***,we find that the increase in the number of charged beads has no signifiant infuence on the time of global iterations and local *** a number of 80×80×80 grids,when the relative error is controlled below 1.5%,the computational efficiency is increased by 8.7 times in the case that contains 500 charged *** adition,for a number of 100×100×100 grids with 100 charged beads,the computational efciency can be increased up to 12 *** work provides new insights for the optimization of iterative algorithms in special problems.

关键词： Finite dfference method Brownian dynamics Charged polymers Electrostatic interaction Local iteration

Insights into Promoting Effect of Sm on Catalytic Performance of the CeO_(2)/Beta Catalyst in Direct Conversion of Bioethanol to Propylene

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Chemical Research in Chinese Universities 2022年第6期38卷 1547-1552页

作者： JIN Huan XU ding TIAN Chao YUE Yinghong HUA Weiming GAO zi Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials Department of ChemistryFudan UniversityShanghai200438P.R.China Shanghai Customs Technology Center of Inspection and Test Shanghai200120P.R.China

A series of Sm-doped CeO_(2)/Beta composite catalysts with various Sm/Ce atomic ratios(0.1–0.4) were prepared by an incipient impregnation method, followed by calcination at 650 ℃. They were characterized by X-ray diffraction(XRD), N2 adsorption, X-ray photoelectron spectroscopy(XPS), Raman, NH3-temperature programmed desorption(TPD) and CO_(2)-TPD. The incorporation of Sm into CeO_(2)/Beta increases obviously the propylene yield for the selective conversion of ethanol to propylene. The promoting effect of Sm on CeO_(2)/Beta can be attributed to two reasons. One is more acetone intermediates are generated on the Sm-doped catalysts due to the enhanced formation of oxygen vacancies. The other is the conversion of acetone intermediate to propylene is enhanced owing to weaker and fewer acid sites on the Sm-doped catalysts.

关键词： Bioethanol Renewable propylene Sm-CeO_(2)/Beta composite Sm doping

Application of Superhydrophobic Surface on Boiling Heat Transfer Characteristics of Nanofluids

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Energy Engineering 2021年第4期118卷 825-852页

作者： Cong Qi Yuxing Wang zi ding Jianglin Tu Mengxin Zhu School of Electrical and Power Engineering China University of Mining and TechnologyXuzhou221116China

Boiling heat transfer is a mode using the phase change of working medium to strengthen the heat exchange due to its good heat exchange capability,and it is widely used in heat exchange *** have been used in the direction of enhanced heat transfer for their superior thermophysical *** wetting,spreading and ripple phenomena of superhydrophobic surfaces widely exist in nature and daily *** has great application value for engineering *** this article,the boiling heat exchange characteristics of nanofluids on superhydrophobic surface are numerically *** was found that with the increase of superheating degree,the steam volume ratio of unmodified heated surface increases to saturation,while the steam volume and evaporation ratio of modified superhydrophobic surface increase firstly and then *** the same time,bubbles are generated and accumulated more fully on superhydrophobic *** was also found that nanofluids with low viscosity are more affected by superhydrophobic surface characteristics,and the increase is more significant with high superheating degree,and the superhydrophobic surface is beneficial to enhancing boiling heat *** with the simulation results,it could be concluded that the boiling heat exchange performance of CuO-water nano-fluids on the modified superhydrophobic surface is better than that of CuO-ethylene glycol nanofluids under high superheating degree.

关键词： Nanofluids superhydrophobic surface pool boiling heat transfer numerical simulation

Numerical study of self-heating effects of small-size MOSFETs fabricated on silicon-on-aluminum nitride substrate

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Nuclear Science and Techniques 2006年第1期17卷 29-33页

作者： ding Yan-Fang ZHU Ming ZHU zi-Qiang LIN Cheng-Lu Department of Electronics Science and Technology East China Normal University Shanghai 200062 China Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences Shanghai 200050 China

Compared with bulk-silicon technology, silicon-on-insulator (SOI) technology possesses many advan-tages but it is inevitable that the buried silicon dioxide layer also thermally insulates the metal – oxide – silicon field-effect transistors (MOSFETs) from the bulk due to the low thermal conductivity. One of the alternative insulator to replace the buried oxide layer is aluminum nitride (AlN), which has a thermal conductivity that is about 200 times higher than that of SiO2 (320 W·m ? 1·K? 1 versus 1.4 W·m? 1·K? 1). To investigate the self-heating effects of small-size MOSFETs fabricated on silicon-on-aluminum nitride (SOAN) substrate, a two-dimensional numerical analysis is performed by using a device simulator called MEDICI run on a Solaris workstation to simulate the electri-cal characteristics and temperature distribution by comparing with those of bulk and standard SOI MOSFETs. Our study suggests that AlN is a suitable alternative to silicon dioxide as a buried dielectric in SOI and expands the appli-cations of SOI to high temperature conditions.

关键词：自热效应微晶管制作衬底硅铝氮化物