VB环境下OpenGL的使用

OpenGL作为事实的工业标准，广泛地应用于二维和三维图形的编程中，但大多工作于C语言的环境下，如何在VB环境下使用它，相关的参考文献较少。本文针对此问题，论述了在Visual Basic环境下，应用第三方函数库VBOpenGL type library进行三维图形编程设计的使用方法。     

Mathematical Simulation of Small Log Ripped by Slasher Saw

Withthesmallsawlogwidespreadused,theuncut-boardsandslabsarecutbythemulti-bitrippingedgerinthejhoberindustw.AfersawingripPed,theunedgedboedaccuratelyvolumeisfAnotherparametCrsaredefinitebyadrawing,theaPProimatevolumeforn1ulateofunedgedboardistx,y,~inatC,x'…     

东北地区野生藤本植物区系分析

东北地区野生藤本植物共有143种,隶属于63属33科。成分特点为双子叶植物科属种最多;小型科属和单种科属较多,而大型科属较少;草本植物占优势。区系成分分析表明:泛热带成分(热带广布)、世界广布成分、北温带成分占总属数55.6%,是本区藤本植物区系的重要组成部分。各类温带成分占83.91%,而热带成分占6.99%,表明藤本植物区系成分为暖温带性质。     

泡桐木材防变色处理配方优选试验研究

为防止泡桐材的变色降等，采用防变色剂、耐光剂、渗透剂组成的防桐木变色剂配方处理桐木板材，观察其对色度ａ＊、ｂ＊、色差ＤＥ＊、明度Ｌ＊的影响。通过正交试验选择最佳工艺参数。处理后的泡桐板材可达到出口一级品之指标，颜色纯洁，保持木材天然本色。     

Study on the biological characteristics ofHomalotglus flaminus

Homalotglus flaminus (Daiman) is an important natural enemy of theChilocorus kuwanae. Its biological characteristic, life history, the action style on hosts were studied at Hongqi Forest Farm, Daqing City, Heilongjiang Province from June 1998 to October 2000, in order to controlH. flaminus and raise the control ability ofChilocorus kuwanae toQuadraspidictus gigas pest. The observed results indicated thatH. flaminus has two generation one year in study area, the pupating span is 12.7 d, life span of females and males is 17.6 d and 10.8 d respectively, egg span is 10 d, and the sex ratio of females to males is 1∶3 Foundation item: This paper was supported by Natural Science and Foundation of Heilongjiang Province. Biography: Mpa Ling (1963), female, Ph. Doctor, associate professor in Northeast Forestry University, Harbin 150040, P. R. China Responsible editor: Song Funan     

港珠澳跨海大桥收费模式研究

由于港珠澳跨海大桥联通三个不同体制的区域，故大桥的合理收费管理模式对大桥的建设有较大影响。本文着重研究了拟建的港珠澳跨海大桥收费模式的基本特征，包括大桥的收费制式、收费方式和收费广场设置情况，为大桥建成后能够顺利运营收费提供了科学的方法。     

灵香草浸膏系列产品的研究

以报春花科珍珠菜属植物灵香草为原料，采用不同的工艺，制取各类浸膏的研究结果。首先采用各种剂对灵香草进行浸提试验，并对得到的乙醇浸膏进行脱色浸膏、净油的研制；对得到的各类产品的物性数据进行研究测试，结果表明乙醇浸膏、脱色浸膏和净油具有许多优良特性，对它们的进一步研究开发有重大意义。     

生态学中关键种与物种重要性的概念(英文)

在本文中,对关键种的概念进行了讨论,并介绍了关键种的典型特征及其在群落和生态系统中的判别。在对关键种的研究基础上,首次提出了物种重要性(SI)概念。物种重要性可以简单地理解为生态系统中物种的重要值,它由三个指数构成,即物种结构重要值(SIV)、功能重要值(FIV)和动态重要值(DIV)。本文同时评价了三大硬阔森林生态系统中乔木树种的物种重要性。     

Fine roots refilling process in an artificial gap in a Picea mongolica forest

Picea mongolica is an endemic but endangered species in China. The spruce forest is only found in sandy forest-steppe ecotones. In this study, we examined the initial response of the quantity and refilling process of fine roots in an artificial canopy gap with a diameter of 36 m in a P. mongolica forest. Under the canopy, the fine root length densities of trees, shrubs and herbs were 2,622, 864 and 3,086 m·m–2, respectively. The fine root biomass of trees, shrubs and herbs were 148, 62 and 65 g·m–2, respect...     

Studies on the population frequency of insects and mites causing galls on the leaves of the sycamore maple<Emphasis Type="Italic"> Acer pseudoplatanus</Emphasis> L. in southern Poland

Species composition of galls on the leaves of Acer pseudoplatanus L. was analysed in 2002 in three localities: the Wolski Forest, near an urban agglomeration of Kraków, the Ojców National Park and the Andrychów Forest District. A total of 12,013 galls were found. The galls were caused by six insect or mite species. The species composition of the galls was identical in the three localities. Artacris cephaloneus (Nalepa) was the most abundant species. The index of occurrence frequency and Agrells index of species co-occurrence were calculated. The index of occurrence frequency (F) value was highest in the case of A. cephaloneus (1.277) and the lowest value, i.e. 0.00005—both from the Wolski Forest. The highest value for Agrells index of species co-occurrence, i.e. 0.900, was found in the case of Eriophyes pseudoplatani Corti and Drisina glutinosa Giard (Ojców National Park), and the lowest,0.050, for D. glutinosa and Coptophylla gymnaspis (Nalepa) (Wolski Forest; Andrychów FD) and for D. glutinosa and Dasineura irregularis (Bremi) (Andrychów FD).