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基于C语言数学计算器设计算法分析
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作者 黄晓军 《集成电路应用》 2020年第12期190-191,共2页
阐述使用C语言编写未知数中的二次方程,三次方程和多个线性方程的解,分析每种方法的操作原理,检查计算结果,包括使用公式方法、牛顿切线方法、Jacobi迭代方法、Gaus-Seidel迭代方法。
关键词 计算方法 C语言 计算器设计
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C语言程序设计中的选择结构应用算法研究 被引量:2
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作者 戚龙 《计算机产品与流通》 2019年第11期225-225,共1页
结构化程序设计语言中三种程序结构分别为顺序结构、选择结构和循环结构,而选择结构又是学习程序设计语言的基础和重点,在程序设计过程中很多学生不能很好的理解和应用选择结构,特别是多选择结构给学生的学习带来了很大的麻烦,本文以C... 结构化程序设计语言中三种程序结构分别为顺序结构、选择结构和循环结构,而选择结构又是学习程序设计语言的基础和重点,在程序设计过程中很多学生不能很好的理解和应用选择结构,特别是多选择结构给学生的学习带来了很大的麻烦,本文以C语言为例重点研究选择结构的应用算法和程序设计。 展开更多
关键词 计算器程序设计 选择结构 IF else语句
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气相色谱仪载气流速校正计算器的设计
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作者 喻旭东 彭勃 罗雄峰 《计量技术》 2016年第3期44-46,共3页
本文对气相色谱仪检定中需进行载气流速校正的原因进行了分析,针对JJG700-1999《气相色谱仪》中给出的校正公式在使用中存在极不方便的问题,编写了一个在Android智能手机上运行的载气流速校正计算器,方便了检定工作中的计算过程。
关键词 气相色谱仪 载气流速校正 计算器设计 计量检测
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Study on Blade Mould CAD/CAM for Hydrodynamic Torque COnverters
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作者 项昌乐 阎清东 吕红梅 《Journal of Beijing Institute of Technology》 EI CAS 1998年第2期172-177,共6页
Aim To develop blade mould CAD/CAM system of torque converter. Methods The mouldconsisted of four parts and an interactive computer program was developed to design a blade mould of torque converter based on UG at wor... Aim To develop blade mould CAD/CAM system of torque converter. Methods The mouldconsisted of four parts and an interactive computer program was developed to design a blade mould of torque converter based on UG at workstation. Results As compar- ed to manual modeling, it is showed in the application that this means not only improves the accuracy of blade shape and manufacture efficiency of converter, but also reduces costs. Conclusion It is proved that this CAD/CAM system is successful, and it opens up widely prospects for design and manufacture of the blade elementsand their moulds. 展开更多
关键词 hydrodynamic torque converter MOULD CAD /CAM
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Simulation and Design Optimization of Ammonia Synthesis Converter 被引量:1
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作者 叶启亮 应卫勇 房鼎业 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2001年第4期441-446,共6页
One-dimensional pseudo-homogeneous model of an axial flow converter and one-dimensional heteroge-neous model of a horizontal converter have been presented, which describe the distribution of gaseous composition,temper... One-dimensional pseudo-homogeneous model of an axial flow converter and one-dimensional heteroge-neous model of a horizontal converter have been presented, which describe the distribution of gaseous composition,temperature and pressure along the height in the two converters, respectively. Design optimization methods of the two converters have been proposed, by which the minimum catalyst volume can be obtained to satisfy the productive capacity of 1000 tons per day, when the operating pressure is 15.0, 10.0 and 7.5 MPa, respectively. 展开更多
关键词 ammonia synthesis axial flow converter horizontal converter mathematical model design optimiza-tion
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AN INVESTIGATION OF RETINEX ALGORITHMS FOR IMAGE ENHANCEMENT 被引量:9
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作者 Lei Ling Zhou Yinqing Li Jingwen 《Journal of Electronics(China)》 2007年第5期696-700,共5页
This letter introduces color constancy and Retinex theory for image enhancement.It clas- sifies Retinex algorithms into four categories and provides their principles and implementations in general.The experimental res... This letter introduces color constancy and Retinex theory for image enhancement.It clas- sifies Retinex algorithms into four categories and provides their principles and implementations in general.The experimental results of Frankle-McCann,MSR (Multi-Scale Retinex) and PNSD (Pro- jected Normalized Steepest Descent) Retinex algorithms are presented and compared.Moreover, variance and average gradient are proposed to evaluate the performance of the different algorithms. 展开更多
关键词 Color constancy RETINEX Frankle-McCann MSR (Multi-Scale Retinex) PNSD (Pro-jected Normalized Steepest Descent)
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Implementation of a new PC based controller for a PUMA robot 被引量:2
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作者 FAROOQ M. 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2007年第12期1962-1970,共9页
This paper describes the replacement of a controller for a programmable universal machine for assembly (PUMA) 512 robot with a newly designed PC based (open architecture) controller employing a real-time direct contro... This paper describes the replacement of a controller for a programmable universal machine for assembly (PUMA) 512 robot with a newly designed PC based (open architecture) controller employing a real-time direct control of six joints. The original structure of the PUMA robot is retained. The hardware of the new controller includes such in-house designed parts as pulse width modulation (PWM) amplifiers, digital and analog controllers, I/O cards, signal conditioner cards, and 16-bit A/D and D/A boards. An Intel Pentium IV industrial computer is used as the central controller. The control software is implemented using VC++ programming language. The trajectory tracking performance of all six joints is tested at varying velocities. Experimental results show that it is feasible to implement the suggested open architecture platform for PUMA 500 series robots through the software routines running on a PC. By assembling controller from off-the-shell hardware and software components, the benefits of reduced and improved robustness have been realized. 展开更多
关键词 Programmable universal machine for assembly (PUMA) robot Computed torque control (CTC) Pulse width modulation (PWM) amplifier Graphical user interface (GUI)
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NEW METHOD OF FORMATION DESIGN FOR BOTH GMTI AND INSAR USING DISTRIBUTED SATELLITES 被引量:1
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作者 Yuan Hao Zhou Yinqing Li Jingwen Sun Muhan 《Journal of Electronics(China)》 2007年第6期821-827,共7页
This letter proposes a method for designing a specific formation of satellites where the flying motion only exists in a circle orbit plane of the reference satellite, which means that the orbit eccentricity is zero. T... This letter proposes a method for designing a specific formation of satellites where the flying motion only exists in a circle orbit plane of the reference satellite, which means that the orbit eccentricity is zero. This method combines the Hill equation, the Kepler equation, and the geometrical inea^ing of orbit elements. It creates the redundancy condition to simplify the deducing process, utilizes multiple conditions to solve the orbit elements for the satellite formation, and obtains the analytical relationship of the orbit elements for the formation satellites with the formation parameters and the orbit elements of the reference satellite. Using these formulations, the orbit elements and formation parameters for the formation satellites can be solved for the given orbit elements of the reference satellite. The letter describes the proposed double-ellipse formation for both GMTI and InSAR, and the validity of the formation is demonstrated via simulation. 展开更多
关键词 Synthetic Aperture Radar (SAR) Double-ellipse formation Dual-interferometry Orbit design
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A Practical SSL Server Performance Improvement Algorithm Based on Batch RSA Decryption 被引量:2
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作者 李世群 吴永东 +1 位作者 周建英 陈克非 《Journal of Shanghai Jiaotong university(Science)》 EI 2008年第1期67-70,共4页
The secure socket layer/ transport layer security(SSL/TLS) handshake protocol uses public key cryptographic algorithms such as RSA for key establishment. Typically, public key cryptographic algorithm is computationa... The secure socket layer/ transport layer security(SSL/TLS) handshake protocol uses public key cryptographic algorithms such as RSA for key establishment. Typically, public key cryptographic algorithm is computational intensive due to the modular multiplications. Therefore, SSL/TLS servers often become swamped while performing public key decryptions when the simultaneous requests increase quickly. A batch RSA decryption algorithm was proposed. The novel algorithm provides the reasonable response time and optimizes server performance significantly. The decryption speedup is proportional to the batch size b, for instance, the speedup factor is 4, while in Shacham's scheme the acceleration rate is only 2.5 when b = 4. 展开更多
关键词 batch decryption secure socket layer (SSL) server public key algorithm
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Fuzzy reasoning model using fuzzy Petri Nets for the monitoring of robotic assembly
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作者 赵杰 高胜 蔡鹤皋 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2007年第5期668-673,共6页
This paper presented a fuzzy Petri net model to deal with the monitoring of robotic assembly. Based on the fuzzy Petri net model, an efficient composite reasoning mode was proposed to perform fuzzy reasoning automatie... This paper presented a fuzzy Petri net model to deal with the monitoring of robotic assembly. Based on the fuzzy Petri net model, an efficient composite reasoning mode was proposed to perform fuzzy reasoning automatiealy. It can determine whether there exists an antecedent-consequence relationship between two contact states. Furthermore, various types of sensor signals can be converted to the same form of real values between zero and one, and the contradiction among large number, high degree of truth and importance of input conditions can be resolved very well by introducing the weight factors and priorities for sensor signals. Finally, a peg- in-the-hole example was given to illustrate the reasonability and feasibility of the proposed model. 展开更多
关键词 fuzzy Petri nets robotic assembly process control contact states monitoring peg-in-the-hole
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Energy-aware Load-balaning Fault-tolerant Routing Scheme for Ad hoc Sensor Networks
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作者 程文青 熊志强 +2 位作者 刘威 杨宗凯 徐永建 《Journal of Shanghai Jiaotong university(Science)》 EI 2008年第1期81-85,共5页
Most routing protocols for sensor networks try to extend network lifetime by minimizing the energy consumption, but have not taken the network reliability into account. An energy-aware, load-balancing and fault-tolera... Most routing protocols for sensor networks try to extend network lifetime by minimizing the energy consumption, but have not taken the network reliability into account. An energy-aware, load-balancing and fault-tolerant routing scheme, termed as ELFR was propsed to adapt to the harsh environment. First a network robustness model was presented. Based on this model, the route discovery phase was designed to make the sensors to construct into a hop-leveled network which is mesh structure. A cross-layer design was adopted to measure the transmission delay so as to detect the failed nodes. The routing scheme works with acknowledge (ACK) feedback mechanism to transfer control messages to avoid producing extra control overhead messages. When nodes fail, the new healthy paths will be selected locally without rerouting. Simulation results show that our scheme is much robust, and it achieves better energy efficiency, load balancing and maintains good end-to-end delay. 展开更多
关键词 wireless sensor networks cross-layer design fault tolerant routing ENERGY-AWARE
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Neutron Radiography System Collimator Design via Monte Carlo Calculation
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作者 H. Jafari M. Shahriari 《Journal of Energy and Power Engineering》 2011年第12期1168-1172,共5页
Neutron radiography uses the unique interaction probabilities of neutrons to create images of materials. This imaging technique is non-destructive. MCNP Monte Carlo Code has been used to design an optimized neutron ra... Neutron radiography uses the unique interaction probabilities of neutrons to create images of materials. This imaging technique is non-destructive. MCNP Monte Carlo Code has been used to design an optimized neutron radiography system that utilizes 241Am-Be neutron source. Many different arrangements have been simulated to obtain a neutron flux with higher amplitude and more uniform distribution in the collimator outlet, next to image plane. In the final arrangement the specifications of neutron filter, Gamma-ray shield and beam collimator has been determined. Simulations has been carried out for a 5Ci 241Am-Be neutron source. In this case 43.8 n/cm2s thermal neutron flux has been achieved at a distance of 35 cm from neutron source. 展开更多
关键词 241Am-Be radioisotope source neutron radiography Monte Carlo collimator.
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Single-particle 3D reconstruction on specialized stream architecture and comparison with GPGPUs
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作者 段勃 Wang Wendi +1 位作者 Tan Guangming Meng Dan 《High Technology Letters》 EI CAS 2014年第4期333-345,共13页
The wide acceptance and data deluge in medical imaging processing require faster and more efficient systems to be built.Due to the advances in heterogeneous architectures recently,there has been a resurgence in the fi... The wide acceptance and data deluge in medical imaging processing require faster and more efficient systems to be built.Due to the advances in heterogeneous architectures recently,there has been a resurgence in the first research aimed at FPGA-based as well as GPGPU-based accelerator design.This paper quantitatively analyzes the workload,computational intensity and memory performance of a single-particle 3D reconstruction application,called EMAN,and parallelizes it on CUDA GPGPU architectures and decouples the memory operations from the computing flow and orchestrates the thread-data mapping to reduce the overhead of off-chip memory operations.Then it exploits the trend towards FPGA-based accelerator design,which is achieved by offloading computingintensive kernels to dedicated hardware modules.Furthermore,a customized memory subsystem is also designed to facilitate the decoupling and optimization of computing dominated data access patterns.This paper evaluates the proposed accelerator design strategies by comparing it with a parallelized program on a 4-cores CPU.The CUDA version on a GTX480 shows a speedup of about 6 times.The performance of the stream architecture implemented on a Xilinx Virtex LX330 FPGA is justified by the reported speedup of 2.54 times.Meanwhile,measured in terms of power efficiency,the FPGA-based accelerator outperforms a 4-cores CPU and a GTX480 by 7.3 times and 3.4 times,respectively. 展开更多
关键词 Stream architecture general purpose graphic processing unit GPGPU) field programmable gate array (FPGA) CRYO-EM
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Quantifying Design Parameters of Symbology Page for Automotive Head up Display
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作者 Gupta Sharad Karar Vinod +2 位作者 Saini Surender Singh Jaggi Neena Bajpai Phun Phun 《Computer Technology and Application》 2011年第8期658-662,共5页
This paper gives an overview of studies on parameters displayed on the Automotive Head Up Display (A-HUD) including calculation and construction of symbology page based on study results. A study has been made on vit... This paper gives an overview of studies on parameters displayed on the Automotive Head Up Display (A-HUD) including calculation and construction of symbology page based on study results. A study has been made on vital parameters required for car drivers and design calculations have been made based on design parameters like field of view, distance from the design eye position, minimum character size viewable from a distance of 1.5m between driver and the projected image, and optical magnification factor. lhe display format suitable for A-HUD applications depends upon the parameters required to be displayed. The aspect ratio chosen is 4:3. This paper also provides method to design the symbology page embedding six vital parameters with their relative positioning and size considering relative position between display device and optical elements which has been considered with a magnification factor of 2.5. The field of view obtained is 6.7° × 4.8°. 展开更多
关键词 Automotive head up display (A-HUD) MAGNIFICATION symbology character size human factors field of view (FOV). design eye position (DEP).
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An Experimental Research of Natural Circulation Heat Transfer for PRHR Heat Exchanger in AP1000
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作者 Minghui Duan Yuzhou Chen +5 位作者 Yvfeng Lv Weiqing Li Keming Bi Wei Wang Kaiwen Du Han Wang 《Journal of Energy and Power Engineering》 2016年第9期545-554,共10页
The heat transfer characteristics of the PRHR (passive residual heat removal) HX (heat exchanger) are very important to reactor design and safety assessment of AP1000. The purpose of the present experiment was to ... The heat transfer characteristics of the PRHR (passive residual heat removal) HX (heat exchanger) are very important to reactor design and safety assessment of AP1000. The purpose of the present experiment was to obtain the natural circulation data in HX to research the heat transfer behavior. The PRHR HX was simulated by three C-type tubes with prototype sizes immerged in a cooling tank. Separate-effect tests of natural circulation in HX tubes have been performed within wide conditions which could cover the operation conditions in AP1000. The experiment provided lots of important data to indicate heat transfer phenomena of PRHR HX. The test conditions were calculated by RELAP5/MOD3.3. The calculation results agreed well with the experiment. RELAP5 could be applied with proper correlations to analyze the heat transfer in PRHR HX under the test conditions. 展开更多
关键词 PRHR HX natural circulation separate-effect tests AP1000
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The design and calculation of the delayed neutron detection system for PWR and CEFR
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作者 Liu Yupu Qiu Chunhua 《Engineering Sciences》 EI 2009年第4期61-67,共7页
This paper discussed the importance of the delayed neutron detection system.We improved the delayed neutron detection station and delayed neutron detector,so the noise was greatly decreased and the detection efficienc... This paper discussed the importance of the delayed neutron detection system.We improved the delayed neutron detection station and delayed neutron detector,so the noise was greatly decreased and the detection efficiency was greatly increased.After the improvement the stability of the detector was enhanced and the false alarm was eliminated.We introduced the principle of the gas lift pump designed for the sodium cooled fast reactor.A calculation model of the failed fuel detection system of CEFR was proposed,and from the model a code using LabWindows/CVI was developed.The minimum broken area that could be detected by the delayed neutron detection system of CEFR was calculated and the delayed neutron detection signal in a few representative transient conditions during fuel failure happened was stimulated. 展开更多
关键词 REACTOR fuel failure delayed neutron gas lift pump calculation model
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Power Electronic Interface with Islanding Detection and Unbalanced Fault Ride-through Capability
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作者 Nguyen Duc Tuyen Goro Fujita +1 位作者 Toshihisa Funabashi Masakatsu Nomurat 《Journal of Energy and Power Engineering》 2012年第11期1816-1825,共10页
Power electronic interface of dispersed generation plays a very important role in connecting a dispersed generation with utility grids. A power electronic interface not only adjusts the amount of active and reactive p... Power electronic interface of dispersed generation plays a very important role in connecting a dispersed generation with utility grids. A power electronic interface not only adjusts the amount of active and reactive power injecting into a grid but also implements other importance duties as well. In this study, negative-sequence current injection has been fulfilled in three-phase power electronic interface for two important duties besides injecting reference power into utility grids. The first one is for islanding detection, and the other one is to enhance unbalance-fault ride-through capability of dispersed generation. This paper introduces a mechanism of negative-sequence injection based on controlling two separate coordinates of dq-control and explains the effect of negative-sequence injection in limiting the unbalanced currents generated from a dispersed generation. Using adaptive notch filter as a signal processing unit for the three-phase system, negative-sequence components are observed. The performance of entire control system is evaluated by time domain simulations, PSCAD/EMTDC (power systems computer aided design/electromagnetic transients including DC). 展开更多
关键词 Dispersed generation islanding detection negative-sequence components ride-through.
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CAx Process Chain for Automated Laser Drilling of Tool Molds
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作者 Hermann Uchtmann Ingomar Kelbassa 《Journal of Mechanics Engineering and Automation》 2014年第5期427-431,共5页
Rotation sintering, also known as slush molding, is used to manufacture molded skins, such as dashboards or door interior panels for cars. At present, approximately 80% of such molded skins are manufactured using elec... Rotation sintering, also known as slush molding, is used to manufacture molded skins, such as dashboards or door interior panels for cars. At present, approximately 80% of such molded skins are manufactured using electroforms to achieve the complex free-form surfaces, and surface structures, such as leather graining that the industry demands. The manufacture of these electroforms is, however, time-consuming and expensive. This project aims to replace conventional electroforms with laser-drilled molds. Holes in tool molds should be drilled by using laser radiation as part of an automated process. The system consists of a robot with a fiber-laser beam source. A CAx (computer-aided x) process chain has been developed for this purpose in which the CAD (computer-aided design) data of the tool molds are processed, drill hole fields generated, and a machine-specific RC (robot control) program created. Process-specific fundamentals, such as suitable process windows and process control, have been devised to manufacture holes using fiber laser radiation The advantages of the new laser-drilled tool molds may result in substituting them for conventional electroforms, allowing old markets to be re-entered or additional markets to be created and targeted through new molds or lower costs. 展开更多
关键词 Laser drilling fiber lasers tool molds CAx process chain.
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Electro-Mechanical Phase Shifters Based on MEMS Structure
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作者 Antonenko Anton Sergeevish Geraimchuk Michael Dem'yanivich Dubrovka Fedir Fedorovich 《Journal of Mechanics Engineering and Automation》 2013年第7期421-423,共3页
The aim of the study of phase shifter on MEMS (micro-electro-mechanical systems) structures was to minimize the dimensions of the design achievement. Also, the main task was to achieve the reliability and durability... The aim of the study of phase shifter on MEMS (micro-electro-mechanical systems) structures was to minimize the dimensions of the design achievement. Also, the main task was to achieve the reliability and durability of the device. The calculation was based on the optimization technique (step by step) and the modeling of individual parts of the device, namely MEMS-keys that perform the main function--switching. The urgency of this problem is the development and study of one device as a universal, that is, automatically switches from two signals simultaneously. Designs are original and devises are the intellectual property of the authors. The program for modeling phase shifters Computer Simulation Technology Microwave Studio and its results are presented in the paper. 展开更多
关键词 MEMS phase shifter dielectric layer.
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Design and Simulation of Solenoid for Buncher of a Linear Accelerator
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作者 E.E. Basabi F.A. Davani 《Journal of Energy and Power Engineering》 2011年第12期1154-1158,共5页
One of the most important components of a linac is bunchcr. Throughout most of the buncher, the electrons are well forward of the crest and have velocities considerably less than light velocity, thus they arc in a reg... One of the most important components of a linac is bunchcr. Throughout most of the buncher, the electrons are well forward of the crest and have velocities considerably less than light velocity, thus they arc in a region of radial dcfocusing and a considerable fraction of the beam will be lost unless defocusing action is counteracted by some other applied forces. The simplest way to do this is to sct up a longitudinal magnetic field which intcmcts with the radial motion of the electrons and causes them to follow helical orbits through the space occupied by the field. In this paper, five solenoids were designed to provide necessary magnetic field inside the bunchcr. Magnetic field was analytically calculated and compared with simulation results of Computer Simulation Technology (CST). Because of resistance in wires, some amount of energy appears in form of heat, so heat power was calculated analytically and cooling system was designed for these solenoids by Analysis System (ANSYS). 展开更多
关键词 SOLENOID linear acceleration DEFOCUSING cooling system.
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