Comparative studies on the seasonal occurrence, nymphal development and food menu in two giant water bugs,Diplonychus japonicus vuillefroy andDiplonychus major esaki (Hemiptera: Belostomatidae)

Summary We compared the seasonal changes in population density and nymphal development at different water temperatures and under different food conditions between two giant water bugs,Diplonychus japonicus andD. major, in Okayama, Japan. D. japonicus produced 1–2 generations a year, whileD. major was strictly inivoltine. The developmental velocity was higher inD. japonicus than inD. major. The thermal constant ofD. japonicus was less than that ofD. major. These results suggest thatD. japonicus is adapted, to higher water temperature thanD. major. In the field,D. japonicus preyed predominately on Lymnaeidae and Physidae snails, whileD. major preyed on aquatic insects such as dragonfly nymphs.     

日语“虫谚”及其文化特性探讨

日本谚语形式多样、内容包罗万象,是日本语言和文化的重要组成部分。日语中的"虫谚",根据其来源及意义可以分为两大类:一类是实体意义上昆虫的"虫谚";一类是想象中的"虫"的"虫谚"。日语"虫谚"反映了日本文化中关注和珍爱自然、企望与万物融洽相处、观察事物细致入微、喜爱精细化的民族特性。     

搜索引擎安全性的思考

搜索引擎的安全性问题是网络安全问题的一种。本文首先分析了搜索引擎所产生的安全性漏洞并针对这些漏洞提出了技术对策。随后,文章着重探讨了搜索引擎安全性引发的网络安全对道德建设的挑战及其应对措施。     

Threshold-range scaling of excitable cellular automata

Each cell of a two-dimensional lattice is painted one of colors, arranged in a color wheel. The colors advance (k tok+1 mod ) either automatically or by contact with at least a threshold number of successor colors in a prescribed local neighborhood. Discrete-time parallel systems of this sort in which color 0 updates by contact and the rest update automatically are called Greenberg-Hastings (GH) rules. A system in which all colors update by contact is called a cyclic cellular automation (CCA). Started from appropriate initial conditions, these models generate periodic traveling waves. Started from random configurations the same rules exhibit complex self-organization, typically characterized by nucleation of locally periodic ram's horns or spirals. Corresponding random processes give rise to a variety of forest fire equilibria that display large-scale stochastic wave fronts. This paper describes a framework, theoretically based, but relying on extensive interactive computer graphics experimentation, for investigation of the complex dynamics shared by excitable media in a broad spectrum of scientific contexts. By focusing on simple mathematical prototypes we hope to obtain a better understanding of the basic organizational principles underlying spatially distributed oscillating systems.     

基于MVC网络安全标志电子认证系统的设计

为加强互联网信息服务的管理,促进互联网信息服务健康有序的发展,根据国务院颁布的《中华人民共和国计算机信息系统安全保护条例》、《互联网信息服务管理办法》和公安部发布实施的《计算机信息网络国际联网安全保护管理办法》,对三明境内的网站进行网络安全标志电子认证,确保网站内容规范,维护网上正常的治安秩序。本设计与实现对建立互联网备案系统及网络安全标志电子认证系统进行全面阐述。     

计算机2000年问题经纬谈

:通过对如何会产生计算机 2 0 0 0年问题的分析 ,客观地从硬件和软件两个方面介绍如何检测和解决计算机 2 0 0 0年问题 ,从而彻底地解决计算机 2 0 0 0年问题