复f-代数的性质研究

以实f-代数的理论作为基础，给出了半素和有单位元的复，代数的一些性质。证明了逆元存在的一个充分条件；并考察了在正规的条件下，复f-代数何时有乘法分解(M．D)性质和(*)性质。最后对复f-代数中的序理想和代数理想的关系进行了刻画。     

Development of the CAS-IBB single-particle microbeam for localized irradiation of living cells

A single-particle microbeam facility has been constructed at the Key Laboratory of Ion Beam Bioengineering (LIBB), Chinese Academy of Sciences (CAS). The system was designed to deliver a defined numbers of hydrogen ions, produced by a van de Graaff accelerator, in an energy range of 2.0-3.0 MeV, into an area smaller than that of the nucleus of an individual living cell. The beam is collimated by a borosilicate glass capillary that forms the beam-line exit. An integrated computer program recognizes the cells and locates them one by one over the microbeam exit for irradiation. We present technical details of the CAS-LIBB microbeam facility, particularly on the collimator, hardware, control program, as well as cell irradiation protocols available. Various factors contributing to the targeting and positioning precision are discussed along with accuracy measurement results.     

Experimental Study and Numerical Simulation of the Casting-Forging Complex Near Net Forming of Alternator Claw-pole

As a newly developed precision technology, casting-forging complex near net forming process is utilized to produce complex components with a short lead time, low cost and high precision, thus to accelerate the response speed of the market and enhance the competitive power of products. In this paper, the casting-forging complex near net forming process of alternator claw pole was developed and investigated with a combination of experimental and numerical simulation method. Qualified near net workpiece was manufactured, mechanical parameter and relative field information during the forming process was also obtained. While the alternator claw-pole is processed with this technology, the forming force is small, the process is short and the quality of forgings is perfect. Therefore, the complex casting-forging near net forming process of claw-pole is an energy and material saving technology, which will have a vast developing and application prospect in the future.     

P-RC APMP PULPING OF THE TRIPLOID OF POPULUS TOMENTOSA

The technology parameters of P-RC APMP process of the triploid of populus tomentosa and the the comparison of P-RC APMP with one and two stage f pretreatment were investigated in this paper. The results showed that in the chemical pretreatment the s that affected the pulp qualities. The charge of NaOH,y in the first stage of chemical pretreatment,was related to pulp strength. The charge of H2O2 tant pulp.In addition, the ratio of NaOH to H2O2 and the on of chemicals in the first and second stage of impregnation also affected the pulp qualities. The and two-stage P-RC APMP pulp illustrated that the ulp had better brightness and breaking length, lower light scatting coefficient and opacity.     

北京市野鸭湖湿地植物区系分析

通过野外调查对野鸭湖湿地的植物种类进行了统计 ,表明该区域内共有高等植物 35 7种 ,隶属 71科 2 13属 ,同时通过对野鸭湖植物区系的地理成分分析表明 ,野鸭湖地区植物属的分布区类型有 14个 ,分布具有广域性 ,且以温带成分为主 ,热带性质的属起补充成分的作用 .     

高校后勤社会化的管理体制难点解析

关于社会化高校后勤的财务管理,人们有诸多“完美”的设想,但在“社会化”改革的实践中却遇到了很多意想不到的难题。本文分析了难题的成因并提出了解决问题的对策。     

Optimization in the Migration Problem of Mobile Agents in Distributed Information Retrieval Systems

In this paper,we employ genetic algorithms to solve the migration problem (MP).We propose a new encoding scheme to represent trees,which is composed of two parts;the pre-ordered traversal sequence of tree vertices and the children number sequence of corresponding tree vertices.The proposed encoding scheme has the advantages of simplicity for encoding and decoding,ease for GA operations,and better equilibrium between exploration and exploitation.It is also adaptive in that,with few restrictions on the length of code,it can be freely lengthened or shortened according to the characteristics of the problem space.Furthermore,the encoding scheme is highly applicable to the degreeconstrained minimum spanning tree problem because it also contains the degree information of each node.The simulation results demonstrate the higher performance of our algorithm,with fast convergence to the optima or sub-optima on various problem sizes.Comparing with the binary string encoding of vertices,when the problem size is large,our algorithm runs remarkably faster with comparable search capability.     

关于定积分integralfromn=0toa(e~(-x~2)dx)的几种解法

本文在高等数学、数值分析的研究过程中,总结了定积分的几种解法,如重积分法、无穷级数法、数值解法。     

Some Problems of Rails For High-speed Railway of China

Acciording to running experience of high-speed railway abroad,a full attention must be paid to some requirements of specifica-tion of rails for high-speed railway,such as materil mechanical properties,rimension tolernces,straightness,surface flatness and so on.It is suggested that the long-length rails should be laid in high-speed railway,and the feasibility of producing,welding and transporting of long-length rails should be researched.On the basis of technical innovation of domestic manufacturers,it is practicable to lay 50-100mlong-length rails should be researched.On the basis of producing,welding and transporting of long-length homemade rails in high-speed railway of China.The following welding programme of rails for hiah-speed railway can be adiop-ted:50-100m long-lenath rails can be welded as 500m long rail string through flash butt welding in plant,then in field the reid string can be welded through a mobile flash butt welding or thermit welding.As the specification of rails or high-seed railway is rigorous.some related techniques to long-length rails should be researched and practised as soon as possible,including mobile flash butt welding tech-nique,transporting and reinforcing techniques of lon-length rails,etc…     

Design and Research of Class 900 t Railway Box-girder Bridge Erecting Machine

In this article,the current railway box-girder bridge erecting machines at bome and abroad are briefly introduced and analyzed,the research ＆ design situation of class 900t rao wau box-girder bridge erecting machines is described,and also the principle for determin-ing the overall plan and a series of issues much concerning the design of key components of class 900t raihway box-girder bridge erecting machines are deseribed.