定位误差的本质及其计算方法讨论

定位误差的分析和计算是进行工艺装备设计必不可少的重要环节。文中根据工程实践及教学体会，分析了计算定位误差的原因和定位误差的本质，并结合具体的实例．对计算定位误差的三种方法——定义法、合成法、微分法进行了阐述，为正确选择计算方法提供了依据。     

An Improved Particle Swarm Optimization Algorithm Based on Ensemble Technique

An improved particle swarm optimization （PSO） algorithm based on ensemble technique is presented. The algorithm combines some previous best positions （pbest） of the particles to get an ensemble position （Epbest）, which is used to replace the global best position （gbest）. It is compared with the standard PSO algorithm invented by Kennedy and Eberhart and some improved＇PSO algorithms based on three different benchmark functions. The simulation results show that the improved PSO based on ensemble technique can get better solutions than the standard PSO and some other improved algorithms under all test cases.     

Backstepping-based Decentralized PID Controller Design for MIMO Processes

A novel decentralized PID controller design procedure based on backstepping principles is presented to operate multiple-input multiple-output(MIMO)dynamic processes.The first key feature of the design procedure is that a whole MIMO control system is decomposed into multiple control loops,therefore the sub-controllers can be efficiently flexibly designed in parallel prototype. The second key feature is that the decentralized controller has equivalency to those designed by backstepping approach.As a complementary support to the design procedure,the sufficient condition of the whole closed-loop system stability is analyzed via the small gain theorem and it can be proven that the process tracking performance is improved.The simulation results of the Shell benchmark control problem are provided to verify the effectiveness and practicality of the proposed decentralized PID control.     

'Toy problem' as the benchmark test for teleoperation systems

A unified hand/arm master–slave system was developed to conduct dexterous tasks by teleoperation. Both the master and the slave consist of a two-fingered hand and a 3-d.o.f. planer manipulator. The system is also aimed at investigating the bottleneck of autonomous robotic manipulation systems. To evaluate the performance of individual teleoperation systems all over the world under equal conditions, we propose toy block assembling (LEGO® blocks) as the benchmark test for teleoperation systems. Using our hand/arm master-slave system, we announce the measured completion time for assembling some block structures, expecting other research group to try the same task in the future.     

Performance evaluation of ProJet multi-material jetting 3D printer

The purpose of this paper is to quantitatively evaluate the performance of a multi-material jetting 3D printer, ProJet 5500X, especially the capability for micro manufacturing. Unlike other single material 3D printer, ProJet 5500X uses photopolymers as the build material and wax as the support material. The building performance was evaluated by building a modified version of the standard benchmark model with a high-resolution printing mode. The dimensional error, forming quality and surface roughness of the printed parts have been measured and analysed using a microscope, a 3D coordinate measuring machine and a surface profilometer. Using wax as the support material, fine features as small as 0.25?mm, lateral features and sharper edges could all be properly built, despite the rough side surfaces observed in the printed part. Identical features (3?mm pins) were precisely built with an accuracy of 15?µm. The research provides first-hand detailed performance knowledge in the ProJet system for understanding the working principle and comparison with other 3D printing systems.     

Performance evaluation of an automation system — determination of a benchmzrk process

An average “real” process is determined from 55 processes automated by an automation system. This a first step in developing realistic benchmark processes for making objective evaluation tests between the performance of different automation systems. The most important properties of the average process that are independent of the automation system used and that are important performance indicators are presented in the paper.The real process, representing the statistical mean of the process data best, is a papermachine with a pulp making department. The process has 141 analog inputs, 50 binary inputs, 90 analog outputs, 63 binary outputs, 77 motor controls, 8 motor value controls, 308 process interfaces, and 165 displays.     

数字化反应堆高保真中子学程序SHARK研发

SHARK程序是由中国核动力研究设计院新近研发的基于全堆芯确定论非均匀输运理论体系的数字化反应堆软件。该软件从多群数据库的截面与共振数据出发,采用改进子群方法刻画有效共振截面的复杂非均匀效应,采用二维/一维或准三维特征线方法开展堆芯层面非均匀输运计算。目前该程序的定态微观问题计算能力已建立完毕。数值结果显示,SHARK程序对于商用压水堆相关基准问题具有良好的计算精度和效率。     

Neutronics Calculations of HTTR with Several Nuclear Data Libraries

Benchmark calculations for several HTTR core states were performed with four cross-section sets which were generated from JENDL-3.3, JENDL-3.2, ENDF/B-VI.8 and JEFF-3.0 using a continuous energy Monte Carlo code MVP. The core states were a critical approach in which an annular core was formed at room temperature and solid cores at room temperature and at full power operation. Study of k_eff discrepancies caused by difference of the nuclear data libraries and identification of nuclides which have large effects on the k_eff discrepancies were carried out. Comparison of the respective k_eff from calculations and experiments was also carried out. As the results, for each of the HTTR core states, JENDL-3.3 yields a k_eff agreeing with the experiments within 1.5%Δk, JENDL-3.2 yields k_eff agreement within 1.7%Δk, and ENDF/B-VI.8 and JEFF-3.0 yield k_eff agreement within 1.8%Δk. There is little k_eff discrepancy between ENDF/B-VI.8 and JEFF-3.0. The k_eff between JENDL-3.3 and JENDL-3.2 is caused by difference of ²³⁵U data and has temperature dependency. The k_eff discrepancy between JENDL-3.3 and ENDF/B-VI.8 or JEFF-3.0 is mainly caused by difference in graphite data.     

城市基准地价及其地价动态监测分析

城市基准地价是我国地价体系中的重要组成部分，但它是以城市定级为基础而确定的区域土地使用权的平均价格，带有抽象性和局限性，需要从动态的观点来监测分析。     

Japanese Evaluated Nuclear Data Library (JENDL)

Three versions of Japanese Evaluated Nuclear Data Library (JENDL) are briefly explained. The first version, JENDL-1, was made aiming mainly at application to fast reactors. The second version, JENDL-2, was built as a bigger general purpose evaluated nuclear data library. It stores nuclear data for 181 nuclides. It has, however, some drawbacks particularly for fusion neutronics calculation. To remove these drawbacks of JENDL-2 and further extend its applicability, the third version, JENDL-3, has now been made. JENDL-3 includes photon-production data for some nuclides, in addition to the data contained in JENDL-2.