扩散引起的爆破问题研究进展

1　IntroductionProblem 1　 A long- standing question in the theory of differential equations asks whether theaddition of diffusion in a reaction mechanism can cause blow- up in finite time.More specifically,doesthere exist a locally Lipschitz vector field f :Rm→ Rm,a positive definite diagonal m× m matrix D anda smooth bounded function u0 (x) ,such that for all y0 ∈ Rm ,solutions of ODEy (t) =f(y(t) ) ,　 t>0 ;　 y(0 ) =y0 , (1 )exist for all time,but solution to initial- boundary value …     

用拉压不同模量理论计算支座移动引起的超静定结构内力

For statically indeterminate structure, the internal force will be changed with the translation of the supports, because the internal force is related to the absolute value of the stiffness EI. When the tension is different with the compression modulus, EI is the function of internal force and is not constant any more that is different from classic mechanics. In the other words, it is a nonlinear problem to calculate the internal force. The expression for neutral axis of the statically indeterminate structure was derived in the paper. The iterative program for nonlinear internal force was compiled. One case study was presented to illustrate the difference between the results using the different modulus theory and the single modulus theory as in classical mechanics. Finally, some reasonable suggestions were made for the different modulus structures.     

试析我国旅游饭店的分时度假

风靡世界的分时度假是旅游饭店推行的一种新的营销手段.通过对分时度假的概念及发展过程的介绍,分析了我国推行分时度假的可能性和必要性,并就我国旅游饭店推行分时度假提出了相应的对策.     

论地理教学中的学科横向联系

地理学科综合性、边缘性、现实性的特点, 使地理知识与其他学科有广泛的联系, 使地理教学中的学科横向联系成为必然。以地理教学为平台, 加强学科知识间的渗透融通, 对学生发展综合的思维能力、形成有机的知识体系、适应新的高考形势具有积极的作用。     

佛山市大气环境影响评价研究

从大气污染源、污染气象条件、大气污染现状入手,运用大气扩散模式对佛山市环境质量现状进行了模拟,并结合2000年城市总体发展规划,预测估算了大气环境的质量和容量,为该市大气污染的治理和环境管理提供了科学依据。     

On the Culture Elements in Translation

As a form of cultural exchanges,it isn’t avoidable for translation and culture to be closely connected and influenced by each other.In the translation process,target work is influenced by all kinds of cultural elements so that target work is different from source work in some degree.The content of source work remains the same,but the form of that is changed more or less as the result of the target language culture.Sometimes the culture of the source language and that of the target language may be on equal footing complementary but sometimes they might be unequal because of their different position of comparative advantages,one culture is neglected.The cultural elements of translator have a great influence on the target work.The target work is the recreation of the translator.     

“兼语句”的来源及特征

"兼语句"是现代汉语中一个重要的句式,早在先秦时期便已存在。然而,由于对其系统的语法研究开始较晚,此句式直到本世纪三、四十年代才引起人们的关注,学者们的关注,学者们对其解释亦不尽相同。文章在前人研究的基础上,从认知学角度对"兼语句"的来源及特征进行了分析,揭示了它与连动结构的渊源关系,并指出了它的内涵及特征。     

“门房诛”考辨

门房诛是北魏正式入律的刑法之一,虽实施时间不长,但对源承北朝律法的隋唐律有重要影响。由于北魏律佚失过多,今人对门房诛的具体情况认识不一、误解颇多。真正说来,北魏神麔律中对＂大逆不道＂的处罚即为门房诛,在适刑人员的范围上有明确规定,主要是诛杀与正犯同籍的男性直系血亲者,但不及年八十以上的老人和不满十四的孩童,女性一律没官;非同籍亲属或受牵连但不受诛。这比起秦汉时的夷三族刑来大为减轻,也对隋唐律中族刑的减轻产生了影响。     

Global existence and blow-up of solutions to reaction-diffusion system with a weighted nonlocal source

In this paper, we study a semi-linear reaction-diffusion system with a weighted nonlocal source, subject to the null Dirichlet boundary condition. Under certain conditions, we prove that the classical solution exists globally and blows up in finite time respectively, and then obtain the uniform blow-up rate in the interior.     

中国的城市化与土地制度改革

我国宪法一方面规定城市的土地归国家所有,农村的土地归集体所有,这就意味着无论是公益性还是非公益性土地需求,都必须通过国家的征地行为来满足,必须先变成国有;另一方面《宪法》又明确表明,国家只有出于公共利益的需要,才能对农地进行征收或者征用。现行征地制度中存在着这个二律背反,应进一步创新和完善城市国有土地制度改革和农村集体土地制度改革的基本思路,尤其要重视研究解决城乡建设用地增减挂钩中土地增值的分配、城市化与土地适度规模经营以及农民增收的关系、城乡宅基地同权同价以及粮食安全责任分摊等问题。