广义分布空间中卷积算子可解之充要条件

Ｅｈｒｅｎｐｒｅｉｓ及Ｈｏｒｍａｎｄｅｒ在Ｓｃｈｗａｒｔｚ缓增分布空间中讨论了卷积算子的可解。本文充分利用Ｂｅｕｒｌｉｎｇ广义分布空间中的Ｆｏｕｒｉｅｒ－Ｌａｐｌａｃｅ变换的性质，在Ｂｅｕｒｌｉｎｇ广义分布空间中讨论了卷积算子可解的几个等价条件，进而导出了卷积算子可解的充要条件，并推广了Ｈｏｒｍａｎｄｅｒ的某些结果     

架起传统与现代的桥梁--建筑历史与理论课程体系教学改革的思考

重新审视建筑历史理论教学的目标、内容、教学方式和手段，通过对国内几座有影响的建筑院校的调研，比较各个院校在这些问题及途径上的异同，分析其利弊，以期促进建筑历史与理论课程体系教学的建设和改革．     

Analysis of transient wave scattering from an inclusion with an unilateral smoothly contact interface by BEM

Summary A 2D time-domain Boundary Element Method (BEM) is applied to solve the problem of transient scattering of plane waves by an inclusion with a unilateral smooth contact interface. The incident wave is assumed strong enough so that localized separations take place along the interface. The present problem is indeed a nonlinear boundary value problem since the mixed boundary conditions involve unknown intervals (separation and contact regions). In order to determine the unknown intervals, an iterative technique is developed. As an example, we consider the scattering of plane waves by the cross section of a circular cylinder embedded in an infinite solid. Numerical results for the near field solutions are presented. The distortion of the response waves and the variation of the interface states are discussed. The financial support by the China National Natural Science Foundation under Grant No. 19872001 and No. 59878004 is gratefully acknowledged. The second author is also grateful to the support of the National Science Fund for Distinguished Young Scholars under Grant No. 10025211.     

现代工程图学教学方法及教学手段的研究与实践

根据现代工程图学课程特点及学生学习本门课程存在的问题,通过对传统教学和多媒体教学的利弊分析,提出了传统教学与多媒体教学有机结合是现代工程图学课堂教学有效的教学模式的观点,介绍了适应课堂教学的多媒体课件的制作方法.同时,提出了网络教学是远程学习、选修课学习和课外学习有效的教学模式的观点,介绍了网络教学的特点、教学方法及现代工程图学网络教学系统的内容.     

Flow-injection spectrophotometric determination of sulfadiazine and sulfamethoxazole in pharmaceuticals and urine.

A rapid and sensitive flow-injection spectrophotometric method is proposed for the determination of sulfadiazine and sulfamethoxazole. This method is based on the diazotization of sulfonamide with sodium nitrite, and a coupling reaction of the diazo-compound with alpha-naphthylamine. The optimum experimental conditions are obtained by using the controlled and weighted centroid simplex method. The linear ranges for the determination of sulfadiazine and sulfamethoxazole are 0.2-20 microg ml(-1) and 0.1-20 microg ml(-1), and their detection limits are 0.06 microg ml(-1) and 0.05 microg ml(-1), respectively, and the sampling frequency is 130 samples per hour. The method has been used to determine sulfadiazine and sulfamethoxazole in pharmaceuticals and urine without separation. The results are in agreement with those obtained by a high-performance liquid chromatograph technique at the 95% confidence level.     

Positive periodic solution of two-species ratio-dependent predator–prey system with time delay in two-patch environment

In this paper, we are concerned with the existence of positive periodic solution to a class of two-species ratio-dependent predator–prey diffusion model with time delay. By using the continuation theorem of coincidence degree theory, we transform this problem into a problem of calculating the topological degree of a continuous mapping, and then some sufficient conditions of the existence of positive periodic solution is established for the system.     

J/ψ Dissociation in QGP via Multi-gluon Absorption

We propose that the suppression of J/ψ production in relativistic heavy ion collisions may be explained by that J/ψ dissociates via absorbing multi-gluons in the environment of quark-gluon-plasma (QGP) where abundance of gluons is expected.     

基于累积损伤过程的不完全预防维护决策

基于累积损伤过程研究旧系统的不完全预防维护策略,冲击服从非时齐Poisson过程,并产生随机的损伤量,损伤量是加法累加的.系统在累积损伤量达到k或系统运行年龄达到T时进行计划内预防维护.在两次计划内预防维护之间,当累积损伤量达到预定水平K (k K)时,对系统进行计划外维护,其费用高于计划内预防维护,利用再生过程理论得到单位时间维护成本,讨论在时齐Poisson过程下的时间预防维护策略与水平预防维护策略,同时给出算例.     

山西省部分非试点县农村新型合作医疗的调查

建立推广新型合作医疗的要点是:加大宣传力度;加强领导,发挥政府主导作用;强化监督,加强管理,确保基金安全平稳运行;创新服务机制,完善便民措施,实现服务管理一体化。     

浅论Simulink在抗震教学中的应用

建筑结构抗震教学中的难点之一在于运动微分方程的求解,同时,该课程存在着学时少、内容多的矛盾。本文在分析Simulink软件的主要特征的基础上,提出将该软件引入抗震多媒体教学中能起到积极作用。