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91.
菅利荣 《金陵科技学院学报》1996,(3)
计算机病毒一经出现便象瘟疫一样疯狂地四处传播和蔓延,成为全世界危害计算机系统安全的公害。我校微机实验室的个人微机及网络机普遍受到病毒的侵染,严重地影响了正常的微机教学,如何有效地防治计算机病毒是摆在微机教学面前急待解决的问题。作者在分析计算机病毒的分类、结构及其表现形式的基础上探讨了计算机病毒防治的一般方法,并在实践中摸索了几种防治计算机病毒的有效方法。 相似文献
92.
本文从地形林相图的网格高程数据矩阵出发,将隐藏线消除问题化为隐藏点的清除问题。并在此基础上定义两类隐藏点。通过三维图象的透视投影变换和与森林资源DBASE数据的联网,可绘制彩色森林立体专业图,并成功地解决了铁路线型库的问题。该系统为森林立体专业图奠定理论依据。 相似文献
93.
Shelterbelts (field windbreaks) are an important tool for farming in semi-arid areas but are not commonly used. An obstacle
to the adoption of shelterbelts is the lack of site-specific information about the benefits and costs associated with establishing
and maintaining them. A group of researchers has been developing a modeling system that will estimate site-specific effects,
benefits, and costs for sheltered fields that produce maize or corn (Zea maize) and soybean (Glycine max) in the U.S. Corn
Belt region. Akey component of the modeling system is the use of the CROPGRO-Soybean and CERES-Maize models to simulate yield
response to microclimatic changes acrossa sheltered field. In this work, we tested the ability of both models to simulate
yield in a sheltered field, evaluated the potential yield increase of shelterbelts based on long-term simulations, and compared
the influence of shelter induced changes in temperature and windrun on yield. Both models simulated yield increases due to
shelter. The soybean model was more responsive to microclimatic differences than the maize model. Long-term simulations generally
showed a field level increase in yield due to shelter for maize and soybeans with an average increase of 4.1 and 3.3, respectively.
Change in windrun due to shelter is more important in increasing yield than changes in temperature. The CERES-Maize model
seems to be more sensitive to changes in windrun than the CROPGRO-Soybean model. 相似文献
94.
对计算机条码管理系统进行了介绍,从数据库的构建和利用、系统建设成本分析及构建系统的作用等方面详细阐述了该系统在农作物商品种子质量追溯中的应用。 相似文献
95.
杨晓玉 《农业图书情报学刊》2012,24(7):139-141
浅析了"TP自动化技术、计算机技术"类在《中图法》(第五版)中的变化。从新增类目、删除类目到增补改类目注释以及修改类名等方面给予了介绍和评论。通过介绍,目的是帮助分类标引人员深入理解和掌握"自动化技术、计算机技术"类目的变化,以指导其实践。 相似文献
96.
Sunico SK Hamel C Styner M Robertson ID Kornegay JN Bettini C Parks J Wilber K Smallwood JE Thrall DE 《Veterinary radiology & ultrasound》2012,53(3):266-272
Advances in magnetic resonance (MR) imaging and three-dimensional (3D) modeling software provide the tools necessary to create sophisticated, interactive anatomic resources that can assist in the interpretation of MR images of extremities, and learning the structure and function of limb musculature. Modeling provides advantages over dissection or consultation of print atlases because of the associated speed, flexibility, 3D nature, and elimination of superimposed arrows and labels. Our goals were to create a diagnostic atlas of pelvic limb muscles that will facilitate interpretation of MR images of patients with muscle injury and to create a 3D model of the canine pelvic limb musculature to facilitate anatomic learning. To create these resources, we used structural segmentation of MR images, a process that groups image pixels into anatomically meaningful regions. The Diagnostic Atlas is an interactive, multiplanar, web-based MR atlas of the canine pelvic limb musculature that was created by manually segmenting clinically analogous MR sequences. Higher resolution volumetric MR and computed tomography (CT) data were segmented into separately labeled volumes of data and then transformed into a multilayered 3D computer model. The 3D Model serves as a resource for students of gross anatomy, encouraging integrative learning with its highly interactive and selective display capabilities. For clinicians, the 3D Model also serves to bridge the gap between topographic and tomographic anatomy, displaying both formats alongside, or even superimposed over each other. Both projects are hosted on an open-access website, http://3dvetanatomy.ncsu.edu/ 相似文献
97.
98.
Particulate phosphorus (P) can be transported via soil erosion in overland flow to waters, where it provides a long-term source of P for aquatic biota, and can accelerate freshwater eutrophication. Hence, knowledge of P sources is important for good environmental management. However, data on P, and related Fe, losses from various structures of a post-mining landscape are lacking. A year-long monitoring, and ten short rainfall simulations on plot scale, at ridges and rills and a combination of them, revealed high erosion from bare lignite mining dumps at Schlabendorf-North, Lusatia, Germany. The mean annual soil erosion rate from the year-long monitoring site was 18 × 106 kg km− 2 yr− 1, corresponding to 0.034 g m− 2 min− 1. The erosion rates were lowest at rill plots (1.9–4.4 g m− 2 min− 1), intermediate at ridge plots (14.3–37.1 g m− 2 min− 1), and highest at a combined rill and ridge plot (48.7–63.4 g m− 2 min− 1). These differences in extent were due to small scale differences in morphology and extreme water repellency. The hydrophobicity leads to very low infiltration, thus generating surface runoff even at low rainfall intensities. Loss rates of P and Fe, as deduced from the year-long erosion rate, were 470–650 kg km− 2 yr− 1, and 37.9 × 103–71 × 103 kg km− 2 yr− 1 respectively. However, these P inputs from lignite mining dump erosion, consisting of P-poor (17–90 μg g− 1) tertiary spoil materials, into aborning mining lakes, are negligible since they are accompanied by high Fe inputs, which favour an efficient P co-precipitation in the water column. 相似文献
99.
计算机技术是现代信息科学技术的基础,计算机技术的发展,对高校计算机基础教育也提出了新的挑战和要求。本文就计算机基础教学的现状进行了分析和探讨,并对如何提高计算机基础的教学质量进行了深入的思考。 相似文献
100.
简述计算机房电磁环境的复杂性以及对计算机房电磁屏蔽设计的要点,阐述图书馆计算机房电磁屏蔽的必要性,提出对图书馆计算机房进行电磁屏蔽的设计方法,并举例进行了说明。 相似文献