Beam Line Design of Compact Laser Plasma Accelerator

A compact laser plasma accelerator that is a novel accelerator based on the interaction of ultra-intense laser and plasmas is being built now at Peking University. According to the results of experiments and numerical simulations, a beam line combining the advantages of quadrupole and analyzing magnets is designed to deliver proton beams with energy ranging from 1 to 44MeV, energy spread within ±5% and 10^6-8 protons per pulse. It turns out that the existence of space charge force of protons can be ignored for the increase of transverse and longitudinal envelopes even in the case of 10^9 protons in one pulse. To cope with the challenge to obtain a uniform distribution of protons at the final experiment target in laser acceleration, we manipulate the envelope beam waist in the Y direction to a proper position and obtain a relatively good distribution uniformity of protons with an energy spread of 0-±5%0.

Design Method for Road Reconstruction and Expansion

This article analyzes the method for designing routes in road reconstruction and expansion projects,using an actual engineering project as an example.This includes an overview of a specific road reconstruction and expansion project,an analysis of the preexisting road,the basic principles of the design road project,and an analysis of the design methods and steps.This study aims to offer some guidance for road reconstruction and expansion design.

Design Curves for Mooring Lines of Turret Mooring Systems

This paper presents a series of design curves to aid in the selection of turret mooring systems for tankers based Floating Production Storage and Offloading (FPSO) systems. These curves are appropriate to water depths ranging from 100 m to 600 m. The curves can be used as a preliminary design tool, allowing the designer to quickly evaluate alternative mooring system configurations, including the number of mooring lines, the characteristics of chain and wire rope to be deployed and the. initial tension. With a knowledge of the total environmental force and vessel motion characteristics, the designer can determine the appropriate system for closer evaluation.

Research on Flexible Transfer Line Schematic Design Using Hierarchical Process Planning

Flexible transfer line(FTL)is now widely used in ma ny manufacturing domains to realize efficiently,high quantity and economic prod uction.These manufacturing domains include automobile,tractor,internal-combu stion engine,and so on.In today’s competitive business environment,it is vit ally important for machine tool manufacturers to design flexible transfer line m ore effectively and efficiently according to a wider variety of customer demand s.This paper proposes an approach to a bidding-based flexible transfer line sc hematic design system.By analyzing manual FTL design process,the architecture o f flexible transfer line schematic design system(FTLSDS)is established.The syst em consists:of four processes:part feature modeling,process planning,FTL fac i lity layout and FTL evaluation. For FTL schematic design.a five-level proces s planning strategy named hierarchical process planning method is proposed.This method includes selection of manufacturing feature machining operation;part se t-up planning,feature sequencing,operation sequencing and process plan genera ting.The major decision relies on setup planning.According to the proceeding o f the hierarchical process planning,the structure of reasoning is proposed base d on blackboard.Under this paradigm,a cooperative effort between a hybrid coll ection of knowledge sources is possible.Total reasoning task can be divided int o some subtasks,and recursive-reasoning system is formed.It is convenient for process planning with step-by-step solution.Meanwhile,the blackboard is use d as the global data exchange area during all reasoning process.By using modula r technology,special purpose machine tools can be designed more efficiently and rapidly.The framework of machine modular design system to support machine requ irement design for FTL is established.By synthesizing the FTL evaluation criter ia.five evaluation criteria of flexible transfer 1ine schematic design are take n into account.An exampie is supplied to demonstrate and verify the validity an d feasibility of flexible transfer line schematic design approach.

Design and simulation for large parafoil fix line object homing algorithm

Traditional parafoil homing usually uses a point as object. As the mobility of parafoil is limited by its glide ratio and wind, in some cases when the parafoil scatter area is large, or the glide ratio of parafoil is small, the deviation of its landing point to object point will be arduous to control. Accordingly, during these situations, when parafoil is used in recovery of spacecraft or satellite, the landing area of parafoil can be set as a rectangle, and the object of parafoil can be set as a line segment. The thesis of this work is designing an algorithm for parafoil homing using line segment as object. The algorithm of wind velocity and direction calculation in different flying segments was also investigated. The algorithm designed navigates the parafoil to land into the predestined area and largely reduce the probability of recovery loads falling to unwanted area to damage houses and people.

The design of double line five step ship lock of Three Gorges Project

The general design and layout of the double-line five-step ship-lock,the water delivery technique for high head ship-lock,the key technical problems of fully lined ship-lock and the monitoring techniques for large-scale miter gates and hoisting equipment under complicated operation conditions of Three Gorges Project (TGP) are introduced.Since the operation of ship-lock in 2003,the operation practice has proved that the design techniques are advanced,rational and reliable.The design and construction of the fully lined ship-lock promotes the development of design theory and practice of ship-lock projects,which makes the construction technology of ship-lock in the world reach a new level.

Design of 1000-kV AC Single-Circuit Overhead Transmission Line

The UHVAC 1 000-kV transmission system is so far the one with the most advanced transmission technique applied and highest operation voltage.There are no guidelines or standards available for the design of 1 000-kV overhead transmission line in China.Study on key technologies and design schemes shall be carried out to ascertain the technical principles and construction standards for project construction,which are presented in this paper based on the Southeast Shanxi-Nanyang-Jingmen test and demonstration transmission line.A comparison and analysis of technical data and economic indices between UHV line and other lines are also described.

Research on design system of band conveyer driven by linear friction

The band conveyer driven by linear friction is a new device. It can reduce drivesize and conveyor belt tensity, and increase delivery capacity. It has feasibility and usability particularly in altering the original conveyer and solving the problems of capacity insufficiency. The technology has brought certain difficulty for engineers, because it has certaindifficulty both in theory and in calculation. Therefore, Visual Basic 6.0 programming technology was used to develop a set of 'the design system of the band conveyer driven bylinear friction.' After being proved in the field, it can completely meet the demands of thedesign. This paper introduced its main theory or basis in design, so as to provide relatedtechnical support to this kind of project.

Extending the Civilization Axis Line:The 2008Olympic Venue Designs

On July 14, the 2008 Summer Olympic Venue Design Competition concluded with a U.S.-China joint venture scooping the first prize. The event was held for the conceptual designs of two major venues for the Games ?the Olympic Green and the Wukesong Culture and Sports Center. A total of 87 plans were submitted since the contest was opened in April, 54 for the Olympic Green and 33 for the Wukesong Center.San Francisco-based Sasaki Associates won the top prize for the Olympic Green which was designed in partnership with Tianjin

Research on Rapid Response Schematic Design for Flexible Transfer Line CAPP-Based

To meet the market requirements for Flexible Transf er Line (FTL), which consists of modular NC machining tools of high quality and co st saving, the methodologies and technologies of client-oriented FTL rapid resp onse schematic design CAPP-based, one of the key techniques, are presented in t his paper. In order to achieve this purpose, an integrated system for integrated design of CAD/CAPP/FTL with box-type parts is realized. In this paper, firstly the theory of the conceptual design of FTL based on CAPP is established and the software architecture is developed. The global-domain pr oduct model is put forward to meet with data representation. After the manufactu ring feature is analyzed and decomposed for machining operations, the feature-b ased part unified data model object-oriented is built. Secondly the knowledge- based CAPP system data model is established. The process planning unit model is formed by work element (WE), which is tool-cell based function abstraction meth od, and has unified layers with respect to designing and manufacturing. With WEs through dynamic response and simultaneous structure in process planning, the pr inciple solution for CAPP function system can be implemented. Lastly the mapping from process domain to module design domain is built. The unidirectional select ion process based on fuzzy matching technology is easily dealt with computer. Th e algorithm of decision with fuzzy synthetic evaluation method and technology is applied to estimate the feasibility of the results in local working procedure o f modular NC machine tools and make decision of designs in overall FTL, which co nsists of many different factors. The example shows that the rapid response desi gn in bidding-based FTL scheme design is realized.

Compact Car-Body Surface Design with T-spline Surface

Creating proper B-spline surface models is a very challenging task for designers in car-body surface design.Due to the tensor-product structure of B-spline surface,some undesirable issues of the redundant control points addition,incomplete surface definition and the difficulty of trimming boundary alteration frequently occur,when designing the car-body surface with B-spline surfaces in local-feature-lines construction,full-boundary-merging and visual surface trimming.A more efficient approach is proposed to design the car-body surface by replacing B-spline surface with classical T-spline surface.With the local refinability and multilateral definition offered by Tspline surface,those designing issues related with B-spline surface can be overcomed.Finally,modeling examples of the door,hood and rear-window are given to demonstrate the advantage of T-spline surface over B-spline surface in car-body surface design.

某直列式点火器双路瞎火故障分析与改进

针对某直列式点火器在低温点火试验中出现的双路冲击片点火管瞎火问题,进行了故障定位及原因分析,提出了改进措施并对其有效性进行了试验验证。结果表明:造成双路瞎火故障的原因是点火器转接件焊点异常处的气体间隙弧光放电;提出将2个回路的触发信号时间间隔调整为50μs,按照HB 7262航空产品电装工艺的相关规定细化电装工艺,增加对能量传输通道的介质耐压检测等改进措施。验证试验表明采取改进措施后,消除了弧光放电现象,点火器内的2个爆炸箔表面均有明显的电爆炸痕迹。

山地齿轨交通系统试验线总体设计

齿轨交通是一种在传统轮轨系统走行结构中增加齿轮-齿轨传动系统的创新轨道交通系统。该系统可解决大坡度线路适应性问题,提高山区、丘陵等复杂地形地貌环境轨道交通选线的灵活性,充分满足山地旅游轨道交通需求,应用前景广泛。为满足齿轨交通系统商业应用前的车辆性能及关键工程技术验证,建设一条山地齿轨交通系统试验线,最大坡度达120‰。通过详细介绍该试验线的建设情况、试验列车概况、试验需求分析、总平面设计,以及轨道、路基、工艺、供变电、附属试验设施等主要工程内容,可为类似项目提供参考。

新时代“红色交通线”价值可视化设计研究

目的基于交通文化资源传播的多样性、泛在性、共享性与有效性需求,将红色交通线在特定历史时期及当代的价值引领作用以资源可视化的方式呈现,促进对交通文化的传承和发扬。方法以“可视化文化符号+产品载体”的形式,借助数字化技术实现数据可视化及文化资源物化衍生,以揭示红色交通文化的发展脉络和新时代交通的变迁。涵盖了文化重构、品牌构建、可视化表达、产品设计、周边开发及营销管理等方面,以及系统化的交通文化产品研发途径。结果通过红色交通文化视觉性创意设计实践研究,探寻有效的文化重塑设计方法,以物化手段助力文化推广,实现对红色交通文化当代传承、价值传播的补充。结论以数字化手段提高抽象文化精神在社会普及过程中的接受度。有利于弘扬爱国主义传统、构建集体记忆,对深入研究和探讨红色交通文化,使其在当代得以活化、物化地发扬,以及增强文化自信都具有重要的理论和实践意义。

基于数字孪生的呼叫机生产线虚拟调试技术分析

阐述基于数字孪生技术的呼叫机生产线虚拟调试技术特点。结合系统设计目标和需要,分析关键技术应用,并通过MCD内部编程,结合仿真技术集成,实现基于孪生技术的生产线设计和验证。

PLC技术课程的实践教学设计探究

文章主要探究在PLC实践教学中如何让学生熟练掌握控制原理和编程方法。采用教学做一体化的教学手段和方法,通过学生反复的实践操练,取得了较好的教学效果,体现出实践性教学方法在高职院校专业课教学中的重要性。

镂空重构手法在服装设计中的创新应用

为了打破镂空工艺对材料、技术的使用界限,丰富其在服装设计中的创新应用,通过梳理服装中镂空构型的起源与发展,在镂空重构概念界定的基础上,结合已有案例归纳分析镂空重构的3类实现手法:连接点式镂空、重塑线式镂空以及剪切面式镂空。以连接点式镂空手法为例,进一步探究镂空重构手法在服装设计中的创新实践:一是镂空构型材料层面的创新,将环保理念融入服装设计,实现废弃物升级利用;二是造型表现技术层面的创新,结合立体塑形进行服装造型表现的拓展实践,并对镂空重构手法在服装设计领域的应用前景作了展望。