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医学图象中体积数据的光线跟踪法显示 被引量:4
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作者 罗立民 Jean Louis Coatrieux 《东南大学学报(自然科学版)》 EI CAS CSCD 1992年第6期7-12,共6页
体积图象的显示、处理和分析已成为图象处理和分析研究的一个重要分支。本文提出了一个在微机上实现的显示体积图象的光线跟踪方法以及相应的处理与分析方法,如景物分割;提出和实现了实际中常见的各向异分辨率数据的显示方法,对实际医... 体积图象的显示、处理和分析已成为图象处理和分析研究的一个重要分支。本文提出了一个在微机上实现的显示体积图象的光线跟踪方法以及相应的处理与分析方法,如景物分割;提出和实现了实际中常见的各向异分辨率数据的显示方法,对实际医学图象数据(CT,MRI)的实验结果表明,该方法具有许多优点。 展开更多
关键词 显示 光线跟踪 三维图象 体积数据
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理想气体体积数据换算问题的计算机处理方法 被引量:2
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作者 任庆云 王松涛 《广州化工》 CAS 2011年第8期31-32,共2页
依据理想气体状态方程,以Visual Basic 6.0语言为工具,开发理想气体体积数据换算的处理程序。该程序占用内存小,使用快捷方便,输入数据能迅速显示计算结果。同时经编译可以生成能够脱离Visual Basic单独运行的可执行程序。
关键词 理想气体 体积数据换算 VISUAL Basic 6.0
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三维体积数据截面图获取的算法设计
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作者 林继志 王强 《华侨大学学报(自然科学版)》 CAS 北大核心 2006年第4期445-446,共2页
提出一种获取三维体积数据截面图的算法,它先确定多边形的每一条线段,再求非多边形区域内的每一个像素值.将其程序化后,可对体积数据进行任意方向的截面图求取,从而获得相应的内部断层图像信息.
关键词 三维体积数据 断层图像 点列 插值填充 算法设计
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体积数据可视化方法综述
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作者 刘武周 《内江职业技术学院学报》 2008年第3期67-70,共4页
体积数据的可视化分为直接绘制和间接绘制两种方法。体绘制算法按处理数据域的不同可分为空间域方法和变换域方法。前者是直接对原始的空间数据(体数据)进行处理显示;后者是将体数据变换到变换域,然后再进行处理显示。目前主要空间... 体积数据的可视化分为直接绘制和间接绘制两种方法。体绘制算法按处理数据域的不同可分为空间域方法和变换域方法。前者是直接对原始的空间数据(体数据)进行处理显示;后者是将体数据变换到变换域,然后再进行处理显示。目前主要空间域方法有光线投射法,抛雪球法,错切一变形法和基于硬件的3D纹理映射方法。空间域方法有频域体绘制法和基于小波的体绘制法。 展开更多
关键词 体积数据 可视化 方法
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飞机油箱燃油量体积特性计算与油量测量仿真 被引量:13
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作者 苏三买 常伟 王卉 《计算机测量与控制》 CSCD 北大核心 2011年第9期2091-2094,共4页
飞机油箱体积特性数据库是油量测量计算的基础,直接影响油量测量的精度;针对目前将油箱模型离散化为有限规则单元,再进行叠加计算燃油体积方法存在的通用性差与精度低的不足,文章根据飞机油量传感器测量高度、飞行姿态以及三轴加速度信... 飞机油箱体积特性数据库是油量测量计算的基础,直接影响油量测量的精度;针对目前将油箱模型离散化为有限规则单元,再进行叠加计算燃油体积方法存在的通用性差与精度低的不足,文章根据飞机油量传感器测量高度、飞行姿态以及三轴加速度信息,确定出油平面,并以此作为分割平面,通过CATIA二次开发实现油箱燃油体积特性数据库自动生成;根据特性数据库的特点与机载数据要求,采用后向试探法对数据库进行压缩与优化;模拟飞机油量测量过程,设计油量测量仿真软件,仿真结果表明;油量计算的相对误差小于1%,按所采用方法计算的数据库能达到工程要求。 展开更多
关键词 飞机油量测量 体积特性数据 CATIA二次开发 数据库压缩与优化 油量测量仿真
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The algorithm of 3D multi-scale volumetric curvature and its application 被引量:12
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作者 陈学华 杨威 +2 位作者 贺振华 钟文丽 文晓涛 《Applied Geophysics》 SCIE CSCD 2012年第1期65-72,116,共9页
To fully extract and mine the multi-scale features of reservoirs and geologic structures in time/depth and space dimensions, a new 3D multi-scale volumetric curvature (MSVC) methodology is presented in this paper. W... To fully extract and mine the multi-scale features of reservoirs and geologic structures in time/depth and space dimensions, a new 3D multi-scale volumetric curvature (MSVC) methodology is presented in this paper. We also propose a fast algorithm for computing 3D volumetric curvature. In comparison to conventional volumetric curvature attributes, its main improvements and key algorithms introduce multi-frequency components expansion in time-frequency domain and the corresponding multi-scale adaptive differential operator in the wavenumber domain, into the volumetric curvature calculation. This methodology can simultaneously depict seismic multi-scale features in both time and space. Additionally, we use data fusion of volumetric curvatures at various scales to take full advantage of the geologic features and anomalies extracted by curvature measurements at different scales. The 3D MSVC can highlight geologic anomalies and reduce noise at the same time. Thus, it improves the interpretation efficiency of curvature attributes analysis. The 3D MSVC is applied to both land and marine 3D seismic data. The results demonstrate that it can indicate the spatial distribution of reservoirs, detect faults and fracture zones, and identify their multi-scale properties. 展开更多
关键词 3D multi-scale volumetric curvature adaptive differential operator in wavenumber domain multi-frequency expansion in time-frequency domain fault detection fracture zone data fusion
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PMMA/SAN共混体系的热膨胀系数和等温压缩系数测定 被引量:3
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作者 文纲要 孙昭艳 +1 位作者 杨剑 安立佳 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2002年第2期154-158,共5页
通过溶液共混制得不同组成的聚甲基丙烯酸甲酯 (PMMA)和苯乙烯 -丙烯腈共聚物 (SAN,其中AN的含量约为 30 % (质量 ) )的共混物。利用压力 -体积 -温度 (p VT)膨胀仪对 PMMA、SAN纯组分样品及各共混物分别进行了测量 ,得到了它们的比容 ... 通过溶液共混制得不同组成的聚甲基丙烯酸甲酯 (PMMA)和苯乙烯 -丙烯腈共聚物 (SAN,其中AN的含量约为 30 % (质量 ) )的共混物。利用压力 -体积 -温度 (p VT)膨胀仪对 PMMA、SAN纯组分样品及各共混物分别进行了测量 ,得到了它们的比容 Vsp随温度 T和压力 p变化的关系 (p VT数据 ) ,计算出它们的热膨胀系数 α随温度变化的关系以及等温压缩系数 β随压力变化的关系。在此基础上 ,拟合出共混物的 α和 β分别随组成变化的关系式。此外 ,应用 Tait方程对所有样品的 p 展开更多
关键词 聚甲基丙烯酸甲酯 苯乙烯-丙烯腈共聚物 共混物 压力-体积-温度数据 热膨胀系数 等温压缩系数 Tait方程
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新产品
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《物流技术与应用》 2019年第5期91-91,176,共2页
科纳普展示最新'货到人'工作站Pick-it-Easy Evo在LogiMAT China 2019展会上,科纳普(KNAPPAG)带来了最新的'货到人'工作站Pick-it-Easy Evo解决方案。据介绍,Pick-it-Easy Evo采用模块化设计,工作站可根据具体要求灵活... 科纳普展示最新'货到人'工作站Pick-it-Easy Evo在LogiMAT China 2019展会上,科纳普(KNAPPAG)带来了最新的'货到人'工作站Pick-it-Easy Evo解决方案。据介绍,Pick-it-Easy Evo采用模块化设计,工作站可根据具体要求灵活扩展,提供各种配置可能性;并且,除了通过库前端输送线环路与存储系统的经典连接外,还可以直接连接到OSR穿梭车,从而既节省空间,又保证系统的流线型设计。此外,其设计考虑到广泛的货物和不同的载重单元,负载高达50公斤。由于这种出色的多功能性,工作站适用于不同行业的应用。 展开更多
关键词 电动叉车 机器人 AMR 手动搬运车 穿梭车 永恒力 人机协作 电动搬运车 体积数据
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QTPV Data Model and Algorithm and Its Application to Geological Exploration Engineering 被引量:1
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作者 CHENGPenggen SHIWenzhong +1 位作者 GONGJianya ZHOUGuoqing 《Geo-Spatial Information Science》 2005年第1期64-71,共8页
3D spatial data model and simulating are the core of 3D GIS can be adopted indifferent domains. A data model based on Quasi Tri-Prism Volume (QTPV) has been proposed. QTPVdefinition and its special cases have been dis... 3D spatial data model and simulating are the core of 3D GIS can be adopted indifferent domains. A data model based on Quasi Tri-Prism Volume (QTPV) has been proposed. QTPVdefinition and its special cases have been discussed. Using QTPV and its special cases, irregularnatural geological bodies and regular subsurface engineering can be described efficiently. Theproposed model is composed of five primitives and six objects. Data structures and topologicalrelationship of the fives primitives and three objects describing stratigraphy are designed indetail. Some schemes are designed for the QTPV modelling of stratigraphy and subsurface engineeringaccording to modelling data. The model manipulation method of QTPV cutting by an arbitrary plane isdiscussed. Using VC^(++)6. 0 programming language integrated with SQL database and OpenGL graphiclibrary under windows environment, a system prototype 3DGeoMV has been developed. The experimentresult shows that the QTPV model is feasible and efficient in modelling subsurface engineering. 展开更多
关键词 GIS QTPV data model ALGORITHMS VISUALIZATION subsurface engineering
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Mass Transfer Enhancement of Gas Absorption by Adding the Dispersed Organic Phases 被引量:9
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作者 张志刚 许天行 +2 位作者 李文秀 纪智玲 许光荣 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2011年第6期1066-1068,共3页
Mass transfer enhancement of gas absorption by adding a dispersed organic phase has been studied in this work. Various dispersed organic phases (heptanol, octanol, isoamyl alcohol, heptane, octane, and isooctane) we... Mass transfer enhancement of gas absorption by adding a dispersed organic phase has been studied in this work. Various dispersed organic phases (heptanol, octanol, isoamyl alcohol, heptane, octane, and isooctane) were tested respectively in the experiment. According to the theoretical model and experimental data, the overall volumetric mass transfer coefficient and enhancement factor were obtained under different dispersed organic phase volume fraction and stirring speed. The experimental results indicate that gas-liquid mass transfer is enhanced at different level by adding a dispersed organic phase. The best performance of enhancement were achieved with the dispersed organic phase volumetric fraction of 5% and under an intermediate stirring speed of 670 r·min^-1. Among the organic phases tested in the experiment, alcohols show better performance, which gave 20% higher enhance-ment of overall volumetric mass transfer coefficient than adding alkanes. 展开更多
关键词 gas absorption dispersed organic phase enhancement factor the interfacial area
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Improved Correlation for the Volume of Bubble Formed in Air-Water System 被引量:2
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作者 王红一 董峰 +1 位作者 卞聿晨 谭超 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2011年第3期529-532,共4页
In order to address the bubble formation and movement in air-water two-phase flow,single bubble rising in stagnant water is experimentally studied by digital image processing.Bubbles are released individually from the... In order to address the bubble formation and movement in air-water two-phase flow,single bubble rising in stagnant water is experimentally studied by digital image processing.Bubbles are released individually from the submerged orifices with different diameters(1.81 mm,2.07 mm,2.98 mm,3.92 mm)at different detachment frequency.Images are recorded by a high-speed video camera and processed by digital image processing technique. The factors impacting the formed volume of bubble are discussed.The experimental results showed that a threshold of gas flow rate(400 mm 3 ·s- 1)divides the bubble formation into two regimes:the constant volume regime and the growing volume regime.Especially for the growing volume regime,the surface tension is taken into account.The bubble volume is consisted of two parts:the surface tension impacting part and the gas volume flow rate impacting part.An improved correlation for bubble volume prediction is developed for the two regimes and better coincidence with the experiment data than the previous models is obtained. 展开更多
关键词 high-speed image bubble formed volume gas volume flow rate gas orifice diameter
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Correlation of Shear Viscosity of Nanofluids Using the Local Composition Theory 被引量:5
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作者 M.S. Hosseini A. Mohebbi S Ghader 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2010年第1期102-107,共6页
In this study,a new method is presented to correlate the shear viscosity of nanofluids by local composition theory.The Eyring theory and nonrandom two-liquid(NRTL)equation are used for this purpose.The effects of temp... In this study,a new method is presented to correlate the shear viscosity of nanofluids by local composition theory.The Eyring theory and nonrandom two-liquid(NRTL)equation are used for this purpose.The effects of temperature and particle volume concentration on the viscosity are investigated.The adjustable parameters of NRTL equation are obtained by fitting with experimental data.The calculated shear viscosities for nanofluids of CuO/water with 29 nm particle size,Al2O3/water with two different particle diameters,36 nm and 47 nm,and CuO/(ethylene glycol,water)are compared with experimental data and the average absolute deviation(AAD)is 1.2%,while the results from some conventional models yield an AAD of 190%.The results of this study are in excellent agreement with experimental data. 展开更多
关键词 NANOFLUID VISCOSITY local composition theory nonrandom two-liquid equation Eyring theory
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Real-Time Temperature Control for High Arch Dam Based on Decision Support System 被引量:4
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作者 井向阳 刘杏红 +1 位作者 周伟 常晓林 《Transactions of Tianjin University》 EI CAS 2014年第2期118-125,共8页
It is important and difficult to control the temperature of mass concrete structure during high arch dam construction.A new method with decision support system is presented for temperature control and crack prevention... It is important and difficult to control the temperature of mass concrete structure during high arch dam construction.A new method with decision support system is presented for temperature control and crack prevention.It is a database system with functions of data storage,information inquiry,data analysis,early warning and resource sharing.Monitoring information during construction can be digitized via this system,and the intelligent analysis and dynamic control of concrete temperature can be conducted.This method has been applied in the construction of the Dagangshan Arch Dam in China and has proven to be very convenient.Based on the decision support of this system and the dynamic adjustment of construction measures,the concrete temperature of this project is well-controlled. 展开更多
关键词 concrete arch dam temperature control decision support system pipe cooling MONITORING
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Gas–Liquid Mass Transfer Characteristics in a Gas–Liquid–Solid Bubble Column under Elevated Pressure and Temperature 被引量:3
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作者 靳海波 杨索和 +3 位作者 何广湘 刘德林 佟泽民 朱建华 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2014年第9期955-961,共7页
abstract The volumetric mass transfer coefficient kLa of gases (H2, CO, CO2) and mass transfer coefficient kL on liquid par-affin side were studied using the dynamic absorption method in slurry bubble column reactor... abstract The volumetric mass transfer coefficient kLa of gases (H2, CO, CO2) and mass transfer coefficient kL on liquid par-affin side were studied using the dynamic absorption method in slurry bubble column reactors under elevated temperature and elevated pressure. Meanwhile, gas-holdup and gas-liquid interfacial area a were obtained. The effects of temperature, pressure, superficial gas velocity and solid concentration on the mass transfer coeffi-cient were discussed. Experimental results show that the gas-liquid volumetric mass transfer coefficient kLa and interfacial area a increased with the increase of pressure, temperature, and superficial gas velocity, and decreased with the slurry concentration. The mass transfer coefficient kL increased with increasing superficial gas velocity and temperature and decreased with higher slurry concentration, while it changed slightly with pressure. Ac-cording to analysis of experimental data, an empirical correlation is obtained to calculate the values of kLa for H2 (CO, CO2) in the gas-paraffin-quartz system in a bubble column under elevated temperature and elevated pressure. 展开更多
关键词 Mass transfer characteristicBubble columnElevated pressureElevated temperature
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Low Power Single-Chip RF Transceiver for Human Body Cormunication 被引量:2
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作者 Nie Zedong Guan Feng +1 位作者 Huang Jin Wang Lei 《China Communications》 SCIE CSCD 2012年第9期1-10,共10页
Human body communication is proposed as a promising body proximal comanunication tech- nology for body sensor networks. To achieve low power and slmll volume ill the sensor nodes, a Ra-dio Frequency (RF) application... Human body communication is proposed as a promising body proximal comanunication tech- nology for body sensor networks. To achieve low power and slmll volume ill the sensor nodes, a Ra-dio Frequency (RF) application-specific integrated circuit transceiver tbr Human Body Commnunication (HBC) is presented and the characteristics of HBC are investigated. A high data rate On-Off Keying (OOK)/Frequency-Shift Keying (FSK) modulation protocol and an OOK/FSK delrodulator circuit are introduced in this paper, with a data-rate-to-carrier-frequency ratio up to 70%. A low noise amplifier is proposed to handle the dynamic range problem and improve the sensitivity of the receiver path. In addi-tion, a low power autonmatic-gain-control system is realized using a novel architecture, thereby render-ing the peak detector circuit and loop filter unneces-sary. Finally, the complete chip is fabricated. Simula-tion results suggest receiver sensitivity to be-75 dBm. The transceiver shows an overall power con-smxption of 32 mW when data rate is 5 Mbps, de-livering a P1dB output power of - 30 dBm. 展开更多
关键词 application-specific integrated circuit TRANSCEIVER human body communication
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A Computational Study of Thrust Vectoring Control Using Dual Throat Nozzle 被引量:7
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作者 Choon Sik Shin Heuy Dong Kim +1 位作者 Toshiaki Setoguchi Shigeru Matsuo 《Journal of Thermal Science》 SCIE EI CAS CSCD 2010年第6期486-490,共5页
Dual throat nozzle (DTN) is fast becoming a popular technique for thrust vectoring. The DTN is designed with two throats, an upstream minimum and a downstream minimum at the nozzle exit, with a cavity in between the u... Dual throat nozzle (DTN) is fast becoming a popular technique for thrust vectoring. The DTN is designed with two throats, an upstream minimum and a downstream minimum at the nozzle exit, with a cavity in between the upstream throat and exit. In the present study, a computational work has been carried out to analyze the performance of a dual throat nozzle at various mass flow rates of secondary flow and nozzle pressure ratios (NPR). Two-dimensional, steady, compressible Navier-Stokes equations were solved using a fully implicit finite volume scheme. The present computational results were validated with available experimental data. Based on the present results, the control effectiveness of thrust-vectoring is discussed in terms of the thrust coefficient and the coefficient of discharge. 展开更多
关键词 Compressible Flow Dual Throat Nozzle Thrust Vector Control Shock Wave Supersonic Flow
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