Guaranteed inclusions for the complex generalized eigenproblem

A method is described which produces guaranteed bounds for a solution of the generalized complex eigenproblem. The method extends a similar approach for general systems of nonlinear equations to the special case of complex pencils, where under weaker assumptions stronger assertions can be proved.     

环境放射化学研究中几个问题的讨论

本文从辐射环境保护和公众辐射防护的角度，讨论了放射性核素在环境中的迁移行为，放射性核素与环境介质的相互作用和放射性核素在环境中的形态等涉及到环境放射化学研究方向的问题，并讨论了它们之间相互依存的关系。     

Group decision support system for assessment of problem-basedlearning

Assessment is an important task in problem-based learning (PBL). It has a strong influence on students' approaches to learning and their outcomes. In order to provide an open and fair method of PBL assessment, a group decision support system (GDSS) has been developed. The system uses mathematical decision methods for collecting assessment criteria and their appropriate weights, and databases for storing students' details and data on the assessment criteria. It integrates databases with model bases in a cooperative decision-making environment and is implemented on a client-server platform using a relational database management system. The GDSS has been developed and used to improve the efficiency and quality of assessing students' PBL outcomes     

金刚石光电导探测器研制及在软X光测量中的初步应用

介绍了我们自己设计制造的天然Ⅱａ型金刚石光导探测器的结构，原理，制造工艺，实验标定及其在ＩＣＦ实验中软Ｘ光测量中的应用等。     

双能X射线骨密度仪测定技术研究

以Ｌｕｎａｒ公司ＤＰＸ－Ｌ型双能Ｘ射线骨密度仪为例，研究引起测量误差的主要因素并提出质控措施。用自检模块、腰椎体膜评定仪器的体外测量精度好于１％。对１０位志愿者重复２次测量，体内精度对腰椎，ＭＰＤ（平均百分差）为０．４６，ＣＶ（变异系数）为０．７５；对股骨颈，ＭＰＤ为１．２６、ＣＶ为０．４７；Ｗａｒｄ’ｓ三角区ＭＰＤ为２．０１、ＣＶ为１．１４；大转子ＭＰＤ为１．６６、ＣＶ为０．７２。扫描图像由２位     

Twisted axially loaded rod with shear and compressibility

Summary Stability of a twisted and axially compressed elastic rod is analysed using the Euler method of adjacent equilibrium configuration. The constitutive equations of the rod are assumed in the form that takes into account both shear of the cross-sections and compressibility of the rod axis. It is shown that bifurcation points of the non-linear system of equations describing equilibrium are determined from the linearized system of equations. The influence of shear and compressibility on the critical values of twisting couple and compressive force is obtained. Moreover, the bifurcation pattern is examined by using the Liapunov-Schmidt method.     

INTEGER analysis of two-dimensional polygonal objects

A consistent modelling scheme for digital images is presented, with the grey-level raster image as input and the list-oriented polygonal image as output. The output information consists of two parts: The metric of the polygonal object, represented by coordinates of marked positions, and the global topology, which takes the form of a two-dimensional topologic order. The central problem, which has to be solved, is to select a digital polygon, approximating a digital arc such that the essential feature of the arc is represented at a predefined precision level. The proposed algorithm uses simple incremental calculations of INTEGER quantities to solve the problem.     

Influence of various types of load-dependent supports on the stability of a compressible column model

Summary The nonlinear behaviour and static stability of a compressible elastic column whose flexural resistance changes as it is loaded is studied. A two-degree-of-freedom, compressible rod model of the column is analysed. Various types of load-stiffness relationships are considered. Post-buckling behaviour under static unidirectional loads is investigated. Singularities of the equilibrium paths of the column are classified according to the slenderness ratio of the column and the load-stiffness relationship of its support.On leave from Department of Mechanical Engineering, University of Toronto, 5 King's College Road Toronto, Ontario, Canada, M5S 1A4