模拟区域气候变化的模式系统的建立及其效能检验

建立了一个富有特色的模拟区域气候变化的模式系统．该模式系统对模式中陡峭地形的处理方法进行了改进，并且在云量参数化方案中考虑了大气的动力学结构．其中大气模式与海洋模式和土壤模式简单耦合，和ＧＣＭ单向嵌套以反映大气环流背景对区域气候的影响．通过对模拟结果的比较和检验，发现区域模式对侧边界条件的依赖性很强，客观真实的侧边界条件是模式能够正确模拟区域气候要素的最重要的条件之一．模式分辨率的提高，中尺度强迫如地形高度和下垫面类型的细致刻划，都有利于气候要素场特别是边界层和地表气候状况模拟效果的改善．     

Asynchronous reproduction in three species of crocodilians in south-eastern Amazonia

We studied reproduction of three species of crocodilians, Paleosuchus trigonatus, Caiman crocodilus and Melanosuchus niger, in the Xingu River, near the Belo Monte hydroelectric dam. The periods of laying and hatching of eggs were estimated for each nest before (2013–2014) and after (2016–2017) the river was dammed and the reservoir was formed. Nesting of the three species occurred between August and December, but was largely asynchronous; nest construction peaked in September for P. trigonatus, October for M. niger and November for C. crocodilus. Reservoir filling had little effect on the laying period of any of the species. Nests of P. trigonatus and M. niger were always within 0–12 m of the bank, whereas nests of C. crocodilus, which nests later in the season when flooding is more likely, were up to 100 m from the nearest water body. There was no relationship between distance from water and the number of eggs in nests, suggesting that larger and presumably more experienced females do not lay at different distances from the bank in any of the species.     

Notes on the natural history of Stizus perrisii ibericus Beaumont (Hymenoptera: Sphecidae)

A study of the biology of Stizus perrisii ibericus revealed some aspects about the behaviour of males, the nesting behaviour of females, and larval development. The slow mass provisioning of this species is compared with the provisioning behaviour of S. continuus and S. pulcherrimus. Cocoons are constructed in seven stages although, compared with other species, there are differences in the duration of each stage. Natural enemies of the wasp include miltogrammine flies, several cuckoo wasps, and velvet ants.     

栈在理解PASCAL程序过程(或函数)嵌套调用中的应用

本文利用“数据结构”中“栈”的概念,给出一种描述执行PASCAL语言多层嵌套程序时程序变化过程的方法,利用栈的动态变化清楚地把握嵌套程序的执行流向.     

纸箱印刷估价系统的设计与实现

在对印刷成本分析的基础上,介绍了纸箱印刷估价系统的设计和实现,具体讨论了系统实现的关键问题.     

嵌套类多重接口的COM/DCOM分布式应用

COM/DCOM是突破性的技术 .它是一种与操作系统和编程语言无关的软件构架 ,它将功能软件以即插即用的方式集成到应用中 ,便于软件系统的设计、升级和维护 ,降低成本 ,提高效率 .DCOM是扩展了的COM ,能够支持在局域网、广域网甚至Internet上不同计算机对象之间的通讯 .使用多重接口是COM迈向DCOM必不可少的一步 .这里介绍了COM/DCOM中利用嵌套类实现多重接口的技术 ,并提供了一个设计实例     

使用卡诺图化简嵌套IF语句——以4变量卡诺图和VisualBasic为例

在程序设计时,多条件的IF语句采用多层嵌套方式会使源程序代码冗长,影响源程序的可读性,如果将嵌套IF语句转换成各条件之间的逻辑运算,可以缩短源程序代码,使源程序更加简洁.多条件嵌套IF语句直接改成各条件之间的逻辑运算比较困难,卡诺图是数字逻辑电路设计中常用的逻辑函数化简工具,在VB程序设计中引入卡诺图工具,讨论使用卡诺图简化嵌套IF语句的方法,说明该方法适用范围和注意事项.     

Preserving consensus hierarchies

In numerical taxonomy we often have the task of finding a consensus hierarchy for a given set of hierarchies. This consensus hierarchy should reflect the substructures which are common to all hierarchies of the set. Because there are several kinds of substructures in a hierarchy, the general axiom to preserve common substructures leads to different axioms for each kind of substructure. In this paper we consider the three substructurescluster, separation, andnesting, and we give several characterizations of hierarchies preserving these substructures. These characterizations facilitate interpretation of axioms for preserving substructures and the examination of properties of consensus methods. Finally some extensions concerning the preserving of qualified substructures are discussed.The author is grateful to the editor and the referees for their helpful suggestions and to H. J. Bandelt for his comments on an earlier version of this paper.     

定位系统在水下自动套料切割的应用

介绍了数控等离子切割机在完成钢板套料后，切割机X、Y、Z三轴驱动系统协调工作；割炬在水下工作时，等离子发生器起弧后，霍尔传感器采集到变化的弧压信号，将其反馈到自动高低调节器，完成割炬的定位和高低调节，使割炬在水下沿着套料轨迹对钢板进行自动切割。