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.

Beam Line Design and Construction of Gas Target for a 30MeV Medical Cyclotron

The first medical high intensity cyclotron CYCIAE-30 and its beam line for the isotope production were built in 1994 at China Institute of Atomic Energy.Now,an upgrading beam line system is designed based on the existing beam line of CYCIAE-30 to transport the beam extracted from the cyclotron to a gas target for the new isotope production,including elements location design,optics simulation and magnet design.The machining and installation of all the elements are accomplished based on the design.The beam tuning is finished and the transmission of 96.5% is obtained.

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 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.

OpenRoads Designer软件在云华水库下游灌区总干渠设计中的应用

利用OpenRoads Designer软件,以云南省云龙县云华水库下游灌区工程为例,提出一套适用于线路工程的正向设计方法。实例证明:可精准统计结构工程量及土方开挖量,提高工作效率,降低手动计算的潜在出错率,为类似工程提供参考。

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.

采用Process Designer的白车身焊装生产线工艺规划研究

白车身焊装生产线工艺规划是决定汽车整车生产周期的重要环节。以先进的数字化工厂技术软件——ProcessDesigner为平台,通过创建制造信息模型和工艺过程模型,实现对白车身焊装生产线的生产信息管理和工艺过程规划,构建了白车身焊装生产线工艺规划系统,并详细描述了其工艺规划实现的具体方法和步骤,最后以某型白车身底板焊装线为例,生成了基于规划系统的数字化三维工厂,对规划结果进行了验证。结果表明,利用该系统进行焊装工艺规划能显著缩短工艺规划时间,提高工艺规划的准确性。

城市轨道交通起终点站预留延伸配线形式研究

城市轨道交通起终点站的配线设计直接关乎延伸工程能否顺利衔接,是控制工程投资的重要制约因素。通过对合肥、杭州、宁波等城市的起终点站配线形式调研,分析各种配线形式的设计思路和优缺点,并结合合肥轨道交通2号线东延线的实际工程案例,重点从运营灵活性、工程投资、未来延伸需求、可实施性等角度分析,针对城市轨道交通起终点站预留延伸方案的站后折返线形式,提出一种运营灵活、利于延伸、造价合理的优化方案。

汽车涂装磷化转锆化前处理工艺研究和工程实践

以汽车磷化前处理涂装线为基础,系统地研究了磷化转锆化的工序间适配性、磷对锆化液的影响、锆化薄膜对泳透率的影响等磷化转锆化的关键工艺,以精益设计为原则制定了工艺设计方案、工程设计方案、高效可靠的设备除磷方案及工艺调试方案,最终以12 d为项目周期一次性完成磷化转锆化工艺升级并垂直转产,这些研究结果和工程实践可供同行借鉴。

可变式钢模台车的结构设计

针对复杂断面形式隧道衬砌施工的需求,设计一款可变式钢模台车。该钢模台车具有变跨、变弧、变高功能,能够满足不同断面形式的隧道施工需求。先分析复杂断面形式隧道的施工特点,然后详细介绍可变式钢模台车的总体结构设计方案以及各部分的结构设计方案,旨在为复杂断面形式隧道衬砌施工提供重要的技术支持。

基于无人机巡检的极端环境架空输电线路缺陷检测系统

针对当前极端环境架空输电线路缺陷检测存在的不足,提高极端环境架空输电线路缺陷检测效果,设计基于无人机巡检的极端环境架空输电线路缺陷检测系统。采集环境数据,传送至无人机伺服模块,电子调速器依据数据调节无人机舵机偏转角度与转速,采集架空输电线路图像,图像利传送至地面数据处理中心,缺陷检测单元利用基于决策树方法得到缺陷检测结果。实验证明:系统可以有效检测架空输电线路的断线、断股、绝缘子散落等缺陷,提升架空输电线路的运行安全性。

Simplified design of rock cavern concrete lining to resist shock loading

A simplified method was proposed for the design of concrete lining in underground rock cavern/tunnel against shock loading. The loading may result from the detonation of explosives on ground surface or ground penetration projectiles exploding adjacent to the cavern/tunnel. The resulting problem necessitates the solution of the dynamics of a beam loaded by a transient pressure uniformly distributed over the span. According to mechanical characteristics of the system with rock bolt and shotcrete, a dynamic support design method based on equivalent single degree of freedom （SDOF） was put forward. The SDOF method was applied to obtaining the maximum displacement at the mid-span of the beam, which is often the controlling factor in the blast-resistant design. In the formulation of the problem, the proposed method combines the phenomena of spalling and structural dynamics theory. An example is provided to demonstrate the applicability of this simplified method.

面向酒盒生产线的多模式码垛机器人构型设计及尺度优化

目的针对白酒酒盒生产线后端码垛任务中的单点重复任务及多点灵活任务,提出了一种多模式混联码垛机器人机构。方法对酒盒生产线中常见的码垛模式进行分析,提出了码垛机器人机构的拓扑结构,通过锁定变胞方法实现了机构由2自由度模式向多种不同轨迹的单自由度模式的变换,并对机构的多种模式进行了运动学分析及尺度优化。结果该机构在多种模式下的运动方程均符合码垛机器人实际任务要求,且通过尺度综合优化了机构的结构尺寸。结论设计的多模式混联码垛机器人机构能够适应实际码垛任务中多变的作业轨迹需求,验证了锁定变胞方法在码垛机器人机构设计中的可行性和有效性。

Lessons learned from the “5.12” Wenchuan Earthquake:evaluation of earthquake performance objectives and the importance of seismic conceptual design principles

Many different types of buildings were severely damaged or collapsed during the May 12, 2008 Great Wenchuan Earthquake. Based on survey data collected in regions that were subjected to moderate to severe earthquake intensities, a comparison between the observed building damage, and the three earthquake performance objectives and seismic conceptual design principles specified by the national ＂Code for Seismic Design of Buildings GB50011-2001,＂ was carried out. Actual damage and predicted damage for a given earthquake level for different types of structures is compared. Discussions on seismic conceptual design principles, with respect to multiple defense lines, strong column-weak beam, link beam of shear walls, ductility detailing of masonry structures, exits and staircases, and nonstructural elements, etc. are carried out. Suggestions for improving the seismic design of structures are also proposed. It is concluded that the seismic performance objectives for three earthquake levels, i.e., ＂no failure under minor earthquake level, ＂＂repairable damage under moderate earthquake level＂ and ＂no collapse under major earthquake level＂ can be achieved if seismic design principles are carried out by strictly following the code requirements and ensuring construction quality.