求助！！！通信类专业翻译

燕燕啦啦啦6 2009-03-08 16:18:40 690 浏览

图像处理系统构成该系统硬件主要包括光源照明系统、CCD高速摄像机、图像采集卡、图像处理卡DSP芯片和执行机构CPLD(复杂可编程逻辑器件)等；而软件嵌入在图像处理卡中，包含有效的异纤... 图像处理系统构成该系统硬件主要包括光源照明系统、CCD高速摄像机、图像采集卡、图像处理卡DSP芯片和执行机构 CPLD(复杂可编程逻辑器件)等；而软件嵌入在图像处理卡中，包含有效的异纤检测与识别算法．该算法可实现对图像中各种异纤的分析、识别、统计和决策．高速、高抗干扰的图像处理硬件保证该系统在工业应用中的实时性与可靠性要求． 2．1 系统硬件结构框图该设计方案为基于DSP+CPI D结构的数字图像处理系统．它需要完成图像采集、数字化处理、图像处理、图像分析、图像显示等功能．本系统以TI公司的 TMS320DM642作为主处理器. 系统的整体工作流程为：两侧的线扫CCD摄像机把采集到的图像信号经TVP5150视频解码芯片转化为ITu — RBT．656格式，内嵌同步信号发送到 DM642的VP口．图像的行同步、列同步、场同步信号均内嵌在视频数据流中．对于片内存储资源有限的高速DSP，存储视频数据需借助外部存储空间．为了提高系统实时处理能力，数据传输由EDMA完成，CPU 只用于数据计算．采集视频数据经EDMA 存储到 SDRAM 中，或把数据从视频通道传送到片内RAM 中进行运算．DSP(DM642)对图像进行分析、识别、定位等算法处理，对异纤进行分类识别，经EDMA、 SAA7121H视频编码器，将其信号转换为PAL(50 HZ)制式或NTSC(60 HZ)制式送到外部液晶屏进行显示．其中SDRAM对应DM642上的CE0映射的地址空间，使用2片32位数据总线的同步动态RAM，高 32位存储在一片RAM 中，低32位存储在另一片 RAM 中，满足DM642 64位数据总线要求．SDRAM 在CE0子空间的具体定位为：0x80000000H 一 0x81FFFFFFH．系统的代码固化在FLASH 中， FI ASH 在CE1子空间占据的具体空间定位为： 0x90000000H一0x9007FFFFH．DM642只提供20根外部地址总线，所以CE1子空间Z大寻址范围为1 M ×8位，SEED—VPM642板上CE1子空间除了分配给FLASH 以外，还分配给状态／控制寄存器、UAR— TA、UARTB等资源使用，其中FLASH 只占CE1子空间的前一半的寻址空间，即Z大可寻址范围为512 K×8位，而FLASH 的设计容量为4 M×8位，所以采用分页技术实现对FLASH 的访问，即将整个4 M ×8位的FLASH分成8个512 K×8位的页，而页地址PA21、PA20、PAl9则由页地址寄存器提供(页地址寄存器位于CPLD中)．CF卡接在EMIF卡的CE2 空间，用来存放特征库和识别结果．CPLD是在传统的PAL、GAL基础上发展而来的．与FPGA相比，CPLD比较适合计算机总线控制、存储控制器、DMA控制器、CACHE控制器、图形控制器等I／O密集型应用，且具备无须外部配置ROM、时延可预测等特性．目前的CPLD 普遍基于E2和 FLASH 电可擦技术，可实现100次以上擦写循环．考虑到该系统设计方案，选用了型号为CY37O64P1OO的复杂可编程逻辑器件，工作电压为3．3 V． 2．2 异纤识别软件的开发在软件开发方面，以阐述C6000的CCS(Code Composer Studio)集成开发环境为主线．应用于 C6000的CCS是C60OO系列DSP的主流开发工具，目前已推出3．3版本． CCS是TI公司推出的一个集成性DSP软件开发工具．在一个开放式的插件(plug—in)结构下，CCS内部集成了以下软件工具： (1)C6000代码产生工具(包括C6000的C汇编器、汇编优化器、汇编器和连接器)； (2)软件模拟器； (3)实时基础软件DSP／BIOS； (4)主机与目标机之间的实时数据交换软件RT— DX： (5)实时分析和数据可视化软件．在CCS下，开发者可以对软件进行编辑、编译、调试、代码性能测试和项目管理等所有工作．此外，它还提供了实时分析和数据可视化功能，大大降低了DSP 系统开发的难度，使开发者可以将精力集中在应用开发上展开

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刘时友 2009-03-09 00:00:00

Image Processing System Components The system hardware mainly includes illumination system， CCD high-speed photo Camera， frame grabbers， image processing DSP chip card and executing agencies CPLD (complex programmable logic device)， etc.; and software embedded in the image Treatment card， that contains different effective fiber detection and recognition algorithms. The algorithm can be Implementation of the image in a variety of different fiber analysis， identification， statistics and decision-making. High Speed， high anti-interference of the image processing hardware to ensure that the system in industrial applications Real-time and reliability requirements. 2.1 System hardware block diagram The design program for the DSP + CPI D based on the structure of digital images Processing system. It requires the completion of image acquisition， digital processing， image Office Rationale， image analysis， image display and other functions. This system to TI's TMS320DM642 as the host processor. The overall work flow system as follows: sweep on both sides of the line CCD camera Put image signal collected by the TVP5150 video decoder chip conversion For ITu - RBT. 656 format， the embedded sync signal is sent to the DM642 mouth of the VP. Synchronous line images， are shown simultaneously， and field sync signal Are embedded in video data stream. For chip storage resources are limited high - Speed DSP， stored video data to another external storage space. In order to mention High real-time processing capability， data transmission by the EDMA completed， CPU Used only for data. Collecting video data stored by the EDMA SDRAM， or put data from the video channel sent to the chip RAM In computing. DSP (DM642) for image analysis， identification， set Algorithm and so on， and deal with the different classification of fiber identification， by the EDMA， SAA7121H video encoder， its signal is converted to PAL (50 HZ) format or NTSC (60 HZ) format to the external LCD screen for 显示. SDRAM on one of DM642's the corresponding mapping address CE0 Space， the use of two 32-bit data bus of synchronous dynamic RAM， a high 32 stored in RAM in a low 32 is stored in another film RAM， meet the DM642 64-bit data bus requirements. SDRAM CE0 at specific sub-space defined as: 0x80000000H 1 0x81FFFFFFH. Curing System at FLASH code， the FI ASH at CE1 subspace occupied by the specific spatial location is: 0x90000000H 1 0x9007FFFFH. DM642 only 20 External address bus， so the maximum addressable space CE1 range of 1 M × 8 bit， SEED-VPM642 board apart from the distribution of sub-space CE1 FLASH give away， but also allocated to the status / control register， UAR - TA， UARTB such as the use of resources， only one of FLASH sub-CE1 Spaces of the former half of the address space， that is the largest addressable range of 512 K × 8， while FLASH design capacity of the 4 M × 8 spaces， so Technical implementation of pagination using FLASH visit soon the entire 4 M × 8-bit FLASH is divided into eight 512 K × 8-bit page， and pages to Site PA21， PA20， PAl9 provided by the page address register (page and Register at the site in CPLD). CF card access at EMIF card CE2 Space， used to store and identify the characteristics of the results of the Treasury. CPLD are in the traditional PAL， GAL developed from the foundation up Of. FPGA compared with， CPLD bus more suitable for computer control， Storage controller， DMA controller， CACHE controller， graphics control Such as I / O-intensive applications， and have no need for external configuration ROM， when Extension of predictable characteristics. CPLD generally based on the current E2 and FLASH erasable electric technology， achieve more than 100 write cycle. Test Consideration to the system design， selection of a model of CY37O64P1OO Complex programmable logic device， the working voltage of 3.3 V. 2.2 Identification of different software development defibrase In software development， to the C6000 the CCS (Code Composer Studio) Integrated Development Environment for the main line. Applies to C6000 Series C60OO the CCS are the mainstream of DSP development tools， The current 3.3 version has been launched. CCS is a Introduces TI integrated DSP software development tools. At an open plug-ins (plug-in) structure， CCS within Department integrates the following software tools: (1) C6000 code generation tool (including the C compilation C6000 ， Assembler optimizer， assembler and connectors); (2) software simulator; (3) real-time software foundation DSP / BIOS; (4) between the host and the target real-time data exchange software， RT - DX: (5) real-time analysis and data visualization software. At CCS， the developers of the software can edit， compile， tune Test， code performance testing and project management of all work. In addition， it Provides real-time analysis and data visualization capabilities， greatly reduced the DSP The difficulty of system development so that developers can concentrate on the application of open Hair on

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求助！！！通信类专业翻译: 图像处理系统构成该系统硬件主要包括光源照明系统、CCD高速摄像机、图像采集卡、图像处理卡DSP芯片和执行机构CPLD(复杂可编程逻辑器件)等；而软件嵌入在图像处理卡中，包含有效的异纤... 图像处理系统构成该系统硬件主要包括光源照明系统、CCD高速摄像机、图像采集卡、图像处理卡DSP芯片和执行机构 CPLD(复杂可编程逻辑器件)等；而软件嵌入在图像处理卡中，包含有效的异纤检测与识别算法．该算法可实现对图像中各种异纤的分析、识别、统计和决策．高速、高抗干扰的图像处理硬件保证该系统在工业应用中的实时性与可靠性要求． 2．1 系统硬件结构框图该设计方案为基于DSP+CPI D结构的数字图像处理系统．它需要完成图像采集、数字化处理、图像处理、图像分析、图像显示等功能．本系统以TI公司的 TMS320DM642作为主处理器. 系统的整体工作流程为：两侧的线扫CCD摄像机把采集到的图像信号经TVP5150视频解码芯片转化为ITu — RBT．656格式，内嵌同步信号发送到 DM642的VP口．图像的行同步、列同步、场同步信号均内嵌在视频数据流中．对于片内存储资源有限的高速DSP，存储视频数据需借助外部存储空间．为了提高系统实时处理能力，数据传输由EDMA完成，CPU 只用于数据计算．采集视频数据经EDMA 存储到 SDRAM 中，或把数据从视频通道传送到片内RAM 中进行运算．DSP(DM642)对图像进行分析、识别、定位等算法处理，对异纤进行分类识别，经EDMA、 SAA7121H视频编码器，将其信号转换为PAL(50 HZ)制式或NTSC(60 HZ)制式送到外部液晶屏进行显示．其中SDRAM对应DM642上的CE0映射的地址空间，使用2片32位数据总线的同步动态RAM，高 32位存储在一片RAM 中，低32位存储在另一片 RAM 中，满足DM642 64位数据总线要求．SDRAM 在CE0子空间的具体定位为：0x80000000H 一 0x81FFFFFFH．系统的代码固化在FLASH 中， FI ASH 在CE1子空间占据的具体空间定位为： 0x90000000H一0x9007FFFFH．DM642只提供20根外部地址总线，所以CE1子空间Z大寻址范围为1 M ×8位，SEED—VPM642板上CE1子空间除了分配给FLASH 以外，还分配给状态／控制寄存器、UAR— TA、UARTB等资源使用，其中FLASH 只占CE1子空间的前一半的寻址空间，即Z大可寻址范围为512 K×8位，而FLASH 的设计容量为4 M×8位，所以采用分页技术实现对FLASH 的访问，即将整个4 M ×8位的FLASH分成8个512 K×8位的页，而页地址PA21、PA20、PAl9则由页地址寄存器提供(页地址寄存器位于CPLD中)．CF卡接在EMIF卡的CE2 空间，用来存放特征库和识别结果．CPLD是在传统的PAL、GAL基础上发展而来的．与FPGA相比，CPLD比较适合计算机总线控制、存储控制器、DMA控制器、CACHE控制器、图形控制器等I／O密集型应用，且具备无须外部配置ROM、时延可预测等特性．目前的CPLD 普遍基于E2和 FLASH 电可擦技术，可实现100次以上擦写循环．考虑到该系统设计方案，选用了型号为CY37O64P1OO的复杂可编程逻辑器件，工作电压为3．3 V． 2．2 异纤识别软件的开发在软件开发方面，以阐述C6000的CCS(Code Composer Studio)集成开发环境为主线．应用于 C6000的CCS是C60OO系列DSP的主流开发工具，目前已推出3．3版本． CCS是TI公司推出的一个集成性DSP软件开发工具．在一个开放式的插件(plug—in)结构下，CCS内部集成了以下软件工具： (1)C6000代码产生工具(包括C6000的C汇编器、汇编优化器、汇编器和连接器)； (2)软件模拟器； (3)实时基础软件DSP／BIOS； (4)主机与目标机之间的实时数据交换软件RT— DX： (5)实时分析和数据可视化软件．在CCS下，开发者可以对软件进行编辑、编译、调试、代码性能测试和项目管理等所有工作．此外，它还提供了实时分析和数据可视化功能，大大降低了DSP 系统开发的难度，使开发者可以将精力集中在应用开发上展开

电子，通信类专业英语求人工翻译，软件翻译的别来。: 如题ThetermASICisoftenappliedtofull-customandsemi-customintegratedcircuits.Anotherclassofintegratedcircuitisthatofprogrammablelogic.Theearliestprogrammablelogicdevices(PL... 如题 The term ASIC is often applied to full-custom and semi-custom integrated circuits.Another class of integrated circuit is that of programmable logic.The earliest programmable logic devices(PLDs) were programmable logic arrays(PLAs).Like gate arrays，these consist of arrays of uncomitted logic，but unlike mask-programmable gate arrays，the configuration of the array is determined by applying a large(usually negative) voltage to individual connections. 展开

求助翻译: 问题一：请问“在GF254硅胶板上，取样点板，在254nm紫外光下观察结果”这句话该如何翻译？ZD是不知道“取样点板”怎么翻译问题二：麻烦高手帮忙翻译一下2Results2.1柱色谱分离结果The... 问题一：请问 “在GF254硅胶板上，取样点板，在254 nm紫外光下观察结果” 这句话该如何翻译？ ZD是不知道“取样点板”怎么翻译问题二：麻烦高手帮忙翻译一下 2 Results 2. 1 柱色谱分离结果 The results of separation by column chromatography 柱色谱分离过程中，氯仿∶甲醇95∶5和90∶10洗脱出来的流分经过反复的硅胶柱色谱分离纯化得到组分C3。 2. 2 薄层色谱检测结果 The results of Thin-layer chromatography. 组分C3在GF254硅胶板上展开后，可在254nm紫外灯下直观观测为单点，见图1。 2. 3 GX液相色谱分析和制备单体化合物对组分C3 进行GX液相制备，色谱图显示有4个色谱峰(见图2) ，分离效果较好，收集4个单峰组分，得到4个化合物1～4，对以上4个化合物进行GX液相分析，均为单峰，见图3～4。 3 化合物的结构鉴定通过制备液相收集得到4个化合物，对其中3个化合物进行结构鉴定: 化合物1，淡黄色晶体， UV λmax nm (logε) : 248 nm。E IMS，m / z 501. 3 [M + 1 ] + ，分子量为500。化合物1氢谱显示7个甲基信号;δ1. 02， 0. 93， 0. 78 ( each 3H， s) ， 0. 89 ( 3H， d， J =6. 4Hz) ， 1. 23， 1. 25 ( each 3H， d， J = 5. 2Hz) ， 1. 22(3H， s) ，一个连氧碳上的氢信号δ3. 23 (1H， dd， J= 10 Hz) ，符合三萜化合物的结构，可以证明化合物1为三萜类化合物。化合物2， UV λmax nm ( logε) : 250 nm。E IMS，m / z 515. 3 [M + 1 ] + ，分子量为514。化合物2的氢谱显示7个甲基信号δ0. 77， 0. 94， 1.01， 1. 22， 1. 23 (3H， s) ， 0. 82 (3H， d， 10. 2 Hz) ，一个连氧碳上的氢信号δ3. 22 ( 1H， dd， J = 10. 5Hz) ，一个甲氧基上的氢信号δ3. 66 (3H， s) ，符合三萜化合物的结构，可以证明化合物2为三萜化合物。化合物3， UV λmax nm ( logε) : 254 nm。EIMS，m / z 531. 2 [M + 1 ] + ，分子量为514。化合物2 的氢谱(见附录)显示7 个甲基信号δ0.78， 0. 82， 0. 87， 1. 03， 1. 24， 1. 31 ( 3H， s) ， 1. 17(3H， d， 6. 6 Hz) ，一个乙酰基上的氢信号2. 10(3H， s) ，一个甲氧基团的氢信号3. 68 (3H， s) ，符合三萜化合物的结构，可以证明化合物3为三萜化合物。化合物4结构较复杂，不能确定是三萜化合物。二楼的辛苦了，非常感谢你的回答。不过好像没有明白我的意思，而且有google之嫌。展开

求助：色牢度翻译！: 今天有位客人发了个技术要求，其中有一条Color fastness to washing: change in color 4， Staining: 4-5 (Min)，不知怎样翻译。。。因为我们经常用的是色牢度几级来要求的，请各位高手不吝赐教这到底该怎样翻译才合适~ 谢谢大家先~

求助，英文文献翻译~: PMMA has good compatibility with PVC due to specific interaction of a hydrogen bonding type between carbonyl groups (C=O) of PMMA and hydrogen from (CHCl) groups of PVC (Belhaneche-Bensemra et al.， 2002; Ramesh et al.， 2002). Zhou et al... PMMA has good compatibility with PVC due to specific interaction of a hydrogen bonding type between carbonyl groups (C=O) of PMMA and hydrogen from (CHCl) groups of PVC (Belhaneche-Bensemra et al.， 2002; Ramesh et al.， 2002). Zhou et al. (2001) studied the relationship between the coating thickness of PMMA on the surface of talc and mechanical properties of PMMA-g-talc/PVC composites， and found that there existed a critical thickness. Xie (2001) found that the PMMA coating on talc improved the dispersion of talc in the PVC matrix and enhanced the interfacial adhesion between talc and PVC. There appears to be a critical coating thickness of PMMA on the talc surface for optimum toughening. Quan et al. (2002) reported improved toughness and intension of the PVC composites filled with CaCO3/ACR core-shell complex particles prepared by in-situ emulsion polymerization of acrylic ester. In the present work， PMMA coated on the surface of CaCO3 nanoparticles by in-situ emulsion polymerization was characterized by FT-IR and 1H-NMR. The effects of PMMA thickness and particle fraction on the mechanical properties of PMMA-coated CaCO3 /PVC nanocomposites were also investigated. 展开

求助，英文文献翻译！: 2. Experimental 2.1 Materials Nano-CaCO3 particles (D50: 30−70 nm by TEM (Fig. 1) and BET: ca.17m2·g-1) were supplied by Shanghai Zhuoyue Nanotech Corporation. Methyl methacrylate (MMA， Shanghai Lingfeng Chemicals) was purified ... 2. Experimental 2.1 Materials Nano-CaCO3 particles (D50: 30−70 nm by TEM (Fig. 1) and BET: ca.17m2·g-1) were supplied by Shanghai Zhuoyue Nanotech Corporation. Methyl methacrylate (MMA， Shanghai Lingfeng Chemicals) was purified by distillation under reduced pressure; potassium persulphate (K2S2O8， initiator， Shanghai Lingfeng Chemicals) was of chemical grade. Silane coupling agent A174 (γ-methacryloxypropyltrimethoxysilane) was purchased from Shanghai Yaohua Factory. Polyvinylchloride (PVC， WS-1000S) was supplied by Shanghai Chlor-Alkali Chemical Co.， Ltd. Fig. 1 Morphology of untreated CaCO3 nanoparticles. Fig. 2 Morphology of PMMA-coated CaCO3 nanoparticles. 2.2 PMMA emulsion polymerization on CaCO3 nanoparticles 2.2.1 Surface silanation of nano-CaCO3 particles The nano-CaCO3 particles were homogeneously dispersed in ethanol (solid content 20%) by a sonication dispersion equipment. The slurry was then heated to 80°C with stirring， and the silane coupling agent A174 (5%， calculated based on the weight of nano-CaCO3 particles) was added into the slurry. After the slurry was stirred for 120 min at 80°C， it was filtered and the filter cake was then dried at 120°C in low vacuum for 120 min to obtain silanated CaCO3 powders. 展开

通信方面的英文文献翻译！！: 以下是文献的一部分，愿意帮忙的高手留下邮箱，我把文件发给你，若能完成，加分：SpatialCompressiveSensingApproachForFieldDirectionalityEstimation.I.INTRODUCTIONVarietyoft... 以下是文献的一部分，愿意帮忙的高手留下邮箱，我把文件发给你，若能完成，加分： Spatial Compressive Sensing Approach For Field Directionality Estimation. I. INTRODUCTION Variety of techniques for field directionality estimation were studied in literature [1]-[5]. Thus， a theoretical analysis of the relationship between the hydrophone array output and the noise field was conducted in [1]-[5]. The developed techniques were based on the array beamformer output or the crossspectral matrix between outputs of array elements [4]-[5]. The problem of a field directionality estimation in ocean， using horizontal line towed array was also addressed in literature [5]- [8]. Recently， problems of direction of arrival and field directionality estimation for moving sensors arrays have attracted renewed interest [9]-[12]. It was shown that an array motion can improve an array performance assuming temporal coherence of successive samples [10]-[11]. In [12]， the wavefield sampling method that exploits the linear relationship between the noise field and the collection of beamformer outputs over various array orientations was proposed. It was shown that the wavefield sampling (WS) method outperforms other tested methods. This algorithm was implemented via the recursive estimation method and its convergence to the unique solution was promised for a specific set of array orientations and beamformer look directions. However， a method for a proper array orientation and beamformer look direction sequence selection remains an open question. The quality of the field directionality estimation is determined by the angular resolution. The higher angular resolution is， the more accurate estimation of the far field sources， and better detection performance can be achieved. One of fundamental relations in the array signal processing is that the angular resolution is directly proportional to the number of the array elements [13]. This relation motivates the desire for longer arrays that can achieve higher resolution. Unfortunately， the requirement contradicts the implementation and installation limitations that motivate shorter arrays. Moreover， implementation of longer arrays for maneuvering platforms such as unmanned underwater vehicles (UUV) can even be impossible [14]. These contradictions motivate the quest for alternative array signal processing methods. Usually， the field directionality is modeled as a finite set of strong far-field narrow-band sources and an isotropic lowpower noise [1]. In this work， the model of the field directionality is adopted in the following way. First， the bearing angle space is uniformly sampled into a large number of discrete angles. Next， it is assumed that ether the high energy that corresponds to the far-field strong sources or the low-energy that corresponds to the isotropic noise is received at the sensor array from every of these discrete azimuth angles. 展开

医学类专业分类:

求助三菱FX2N PLC Modbus rtu 通信问题:

求助三菱FX2N PLC Modbus rtu 通信问题:

技术类专业有哪些？:

机械类专业哪个好？: 机械制造与自动化？磨具设计与制造？数控技术？还是机械设计..... 请各位朋友帮下忙···

高分求助化工外贸术语翻译，关于高分子材料的，多谢: MATERIAL DESCRIPTION LDPE SECOND PRIME GRADE CLEAN MFI �C 2. 3 G/10MIN PET NEAR PRIME GRADE BOTTLE GRADE IV �C (MIN) 82 (MAX) 84 G/10MIN LLDPE FILM SECOND PRIME GRADE TR PP SECOND PRIME GRADE PELLETS MFI- 8 ... MATERIAL DESCRIPTION LDPE SECOND PRIME GRADE CLEAN MFI �C 2. 3 G/10MIN PET NEAR PRIME GRADE BOTTLE GRADE IV �C (MIN) 82 (MAX) 84 G/10MIN LLDPE FILM SECOND PRIME GRADE TR PP SECOND PRIME GRADE PELLETS MFI- 8 - 20 G/10MIN HDPE SECOND PRIME GRADE PELLETS CLEAN MFI- 2- 2.5 G/10MIN HDPE SECOND PRIME GRADE PELLETS 5% POWDER MFI- (MIN) 3 (MAX) 4 G/10MIN MIXED PP/HD SECOND PRIME GRADE CLEAN MFI- (MIN) 3 (MAX) 5 G/10MIN PET SECOND PRIME GRADE PELLETS TRANSPERANT MFI- (MIN) 57 (MAX) 60 G/10MIN PET SECOND PRIME GRADE LUMPS REGRIND WHITE LDPE REPROCESS FILM GRADE PELLETS BLACK LDPE REPROCESS FILM GRADE SORTED PP INJECTION GRADE PELLETS BLACK PP INJECTION GRADE PELLETS WHITE HDPE INJECTION GRADE PELLETS SORTED HDPE REPROCESS BLOW GRADE PELLETS PTA POWDER WHITE PTA POWDER YELLOWISH HDPE BLOW BOTTLES BALED (TR+WHITE) HDPE BLOW BOTTLES BALED MIX COLOR PET REGRIND LUMPS MIX PET PREFORM AS IT IS GREEN PET PREFORM AS IT IS MIX COLOR PET FLAKES HOT WASHED GREEN PA BALED PP RAFFIA BAGS GOOD LDPE FILM BALED BLACK MIX ABS REPROCESS PELLETS PS LUMPS REGRIND YELLOWISH PS RECYCLED GRANULES SORTED COLOR PS REGRIND MIX COLOR PS REGRIND TRANSPARENT PS REGRIND WHITE COLOR PC WATER BOTTLES REGRIND BLUE PET BALED TRANSPARENT PET BALED GREEN PVC RIGID REGRIND PIPE GRADE GREEN PVC RIGID REGRIND PIPE GRADE MIX COLOR PVC REGRIND PROFILE GRADE WHITE PVC SHEETS MIX COLORS PVC SHEEETS TRANPARENT 展开

求助：帮忙帮忙，机械英语NB的帮忙翻译下: The effect of beam diameter on the electron skirt in a high pressure scanning electron microscope R. Belkorissata， A. Kadouna， B. Khelifab， C. Mathieub，* aLaboratoire d’Elaboration et de Caracte´risation des Mate´riaux， Univ... The effect of beam diameter on the electron skirt in a high pressure scanning electron microscope R. Belkorissata， A. Kadouna， B. Khelifab， C. Mathieub，* aLaboratoire d’Elaboration et de Caracte´risation des Mate´riaux， Universite´ Djilali Liabe`s de Sidi Bel-Abbes， BP 89， 22000 Sidi Bel-Abbe`s， Algeria bCentre de Calcul et de Mode´lisation de Lens， University D’Artois， Faculte´ Jean Perrin， SP 18 Rue Jean Souvraz， 62307 Lens cedex， France Received 9 February 2004; accepted 19 March 2004 Abstract Helium gas and air are commonly used in the high pressure scanning electron microscope (HPSEM). The presence of a gaseous environment in the specimen chamber modifies the electron beam profile. In order to fully understand the beam-gas interaction， we have investigated the beam-diameter effect for two gases (helium and air) by Monte Carlo simulation. In this calculation， we have assumed that the electron beam is Gaussian and we have explored the influence of the nature of the gas at low voltage. When the beam diameter varies between 1 and 100 nm， there is no influence on the beam profile for these two gases. The resolving power of the HPSEM is not affected by the beamgas interaction. These theoretical results have been compared with experimental images obtained at low voltage under air and helium gases. The variation of image quality at low voltage has confirmed the interest of helium for use in a Field Emission Gun SEM (FEGSEM) in high pressure (or low vacuum) conditions. q 2004 Elsevier Ltd. All rights reserved. Keywords: High pressure scanning electron microscope; Monte Carlo; Electron scattering; Electron profile; Skirting 展开

华南理工大学有数控机械类专业吗:

延安大学有中医类专业吗？:

哪些大学有多肽类专业:

现场总线，串行通信，并行通信，以太网通信？: 如何区分，他们之间的关系，求详解... 如何区分，他们之间的关系，求详解展开

天津中医药大学学师范类专业的可以考研时学中医类专业吗:

北大医学部有中医类专业吗?: 如果没有的话为什么啊??... 如果没有的话为什么啊?? 展开

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