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101.
湿地生态系统是与森林和海洋并列的三大生态系统之一,在全球气候和环境保护中发挥着非常重要的作用,因此,湿地的监测对环境保护和人类健康至关重要。本文以渤海湾-莱州湾为研究区域,利用环境与灾害监测预报小卫星(简称HJ-1)CCD图像通过分层分类法提取滨海湿地的分布,并以黄骅市为例对湿地的变化进行景观格局的动态分析。结果表明,利用HJ-1 CCD图像进行滨海湿地的监测是可行的,且与Landsat图像相比HJ-1 CCD数据具有高获取频率和宽覆盖范围,从而可以为湿地分布和变化的监测与管理提供经济有效的支撑。对湿地景观格局的评价表明,由于人类活动的影响,近年来湿地景观正在悄然地发生变化,天然湿地逐渐减少,人工湿地相对增多,人类的影响正日益加剧,需要引起重视。 相似文献
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Non-traditional Monte Carlo simulations are a powerful approach to the study of systems with complex energy landscapes. After reviewing several of these specialized algorithms we shall describe the behavior of typical systems including spin glasses, lattice proteins, and models for “real” proteins. In the Edwards-Anderson spin glass it is now possible to produce probability distributions in the canonical ensemble and thermodynamic results of high numerical quality. In the hydrophobic-polar (HP) lattice protein model Wang-Landau sampling with an improved move set (pull-moves) produces results of very high quality. These can be compared with the results of other methods of statistical physics. A more realistic membrane protein model for Glycophorin A is also examined. Wang-Landau sampling allows the study of the dimerization process including an elucidation of the nature of the process. 相似文献
105.
张俊 《电脑编程技巧与维护》2013,(8):113-114
介绍了硬盘保护系统的主要功能和在计算机实验室的实际应用,阐述了硬盘分区规划、实验室机器IP地址的自动分配、硬盘保护系统的使用技巧。 相似文献
106.
This study investigated the effect of moving from small offices to a landscape environment for 19 Visual Display Unit (VDU) operators at Alcatel Denmark AS. The operators reported significantly improved lighting condition and glare situation. Further, visual discomfort was also significantly reduced on a Visual Analogue Scale (VAS). There was no significant correlation between lighting condition and visual discomfort neither in the small offices nor in the office landscape. However, visual discomfort correlated significantly with glare in small offices i.e. more glare is related to more visual discomfort. This correlation disappeared after the lighting system in the office landscape had been improved. There was also a significant correlation between glare and itching of the eyes as well as blurred vision in the small offices, i.e. more glare more visual symptoms. Experience of pain was found to reduce the subjective assessment of work capacity during VDU tasks. There was a significant correlation between visual discomfort and reduced work capacity in small offices and in the office landscape. When moving from the small offices to the office landscape, there was a significant reduction in headache as well as back pain. No significant changes in pain intensity in the neck, shoulder, forearm, and wrist/hand were observed.The pain levels in different body areas were significantly correlated with subjective assessment of reduced work capacity in small offices and in the office landscape.By careful design and construction of an office landscape with regard to lighting and visual conditions, transfer from small offices may be acceptable from a visual-ergonomic point of view. 相似文献
107.
This paper contributes a comprehensive study of a framework to bound worst-case instruction cache performance for caches with arbitrary levels of associativity. The framework is formally introduced, operationally described and its correctness is shown. Results of incorporating instruction cache predictions within pipeline simulation show that timing predictions for set-associative caches remain just as tight as predictions for direct-mapped caches. The low cache simulation overhead allows interactive use of the analysis tool and scales well with increasing associativity.The approach taken is based on a data-flow specification of the problem and provides another step toward worst-case execution time prediction of contemporary architectures and its use in schedulability analysis for hard real-time systems. 相似文献
108.
儿童活动场所的景观作为居住区整体景观形象的重要组成部分,不仅仅是简单的表面美化的设计,更重要的是对居住区儿童生理和心理需求方面的满足。依据以人为本的设计理念,针对当前居住区儿童景观设计的发展情况进行反思与探讨,以期引起更多的人们对于儿童这个特殊群体的关注,创造适宜他们健康成长的场所景观。 相似文献
109.
胡秋霞 《数码设计:surface》2008,(7):214-216
材质是建构壁画形式美的重要因素之一。第十届全国美展壁画作品充分运用材质美感来加强壁画艺术的感染力,这些壁画无论使用那种类型的材料,这些材料都能各显其长,与建筑环境达到了统一的、和谐的关系。可见,材料不仅仅是壁画艺术家表现的工具,也是传递艺术家意志与观念的媒介。 相似文献
110.
魏凯旋 《数码设计:surface》2008,(9):100-102
随着旅游业的不断发展,旅游景观设计成为艺术设计中较为热门的专业,它是一种多学科结合并用的特点,即承载着保护大自然的使命,又能给游客以美的感受;它既要从当地的自然条件与地域文化相统一,又要与自然景观所呈现的主题特点相统一。新疆近几年来旅游业不断发展,随着景区的不断开发,要制订一个长期的规划,要想避免盲目性和破坏性,从环保和生态的角度上找到一个和谐的设计风格做为主导是关键。 相似文献