纯火电系统有功最优分配的投影拉格朗日法

本文提出了纯火电系统有功最优分配的投影拉格朗日算法。与经典的协调方程法相比,本算法直接给出了λ的解析表达式,因而求解过程更为简单可靠,且收敛迅速。     

系统还原算法分析

介绍了系统还原算法的设计思想,深入分析了转存缓冲原理,创建了系统还原算法的数据结构,详细描述了系统还原与系统更新的算法工作流程,讨论了未来系统还原的研究方向。     

802.11无线网络WPA安全体系的研究

从现有的无线局域网的安全问题入手,研究了最新的无线局域网安全协议WPA,其中包括了802.1X认证协议和TKIP安全加密算法,并对即将推出的802.11i安全协议进行了介绍。     

Climate change threats to protected plants of China: an evaluation based on species distribution modeling

Climate change poses major new challenges to biodiversity conservation. Distribution ranges of species have been proven to be affected by climate anomalies. Detecting the extent of protected species response to climate change can help formulate flexible conservation strategies to overcome the changing climate. Using species distribution modeling and high resolution climate data, we simulated current distribution patterns of 233 protected plants in China. Those patterns were then projected into future suitable habitats for each species under nine climate change scenarios, with no migration or full migration hypotheses. Under the most extreme climate change scenario （CGCM-B2a）, we evaluated species extinction risks. Sixteen percent of protected plants are expected to lose more than 30 % of their current ranges. By calculating areal shifts, hotspots for emigrants, immigrants, and persistent species were identified under climate change. Flexible conservation strategies were addressed for those regions. Those strategies strongly depend on the migration types of species and sensitivity of the hotspots to changing climate. In hotspots for emigrants, the main conservation strategy is ex situ protection; protected species from these regions should be stored in seed banks or botanical gardens. For hotspots of immigrants, enough space should be maintained for new species, and some measures are necessary to assist dispersal. For hotspots of persistent species, more natural reserves are needed. We highlight related fields that can help conserve protected species in the future, such as conserving the soil seed bank and understanding of the effects of migration ability and interactions between protected species.     

Applications of systematic approaches in freshwater conservation planning

Systematic conservation planning （SCP） is a widely accepted biodiversity-focused approach to selecting priority areas for protection. Since freshwater ecosystems are globally in urgent need of more conservation and the development of freshwater protected areas has lagged behind such need, SCP is proposed to be widely applied in freshwater conservation. As SCP originates from terrestrial realms, freshwater-specific characteristics should be con- sidered when applied to freshwater systems. The chal- lenges mainly include difficulty in data collection for freshwater species and uncertainty in classification of coarse-filters for representation, while also considering the maintenance of natural connectivity in fresh waters and taking longitudinal, lateral, and climate-change-caused threats into account. Only by addressing these issues may the representativeness and persistence of freshwater bio- diversity be ensured in the proposed conservation network. Though challenging at times, the application of systematic approaches in freshwater conservation planning has been widely attempted throughout the last 12 years and applied in different freshwater ecosystems at different scales. In addition, the consideration of freshwater-specific issues has been becoming more and more comprehensive. This review divides the whole process of SCP into successive steps while discussing detailed applications of freshwater planning at each step. First, according to the review, each step attempts to explore many alternatives, such as usingsurrogates from the species level to the ecosystem level （or a combination within this range） to represent the spatial variation of freshwater biodiversity, deriving raw data from various sources to use for planning, applying different techniques to expand or integrate data, setting various target forms to ensure representativeness or persistence, considering existing protected areas in different ways in the process of planning, using priority principles in various paradigms for both representativ     

星斗山自然保护区珙桐种群结构特征研究

对星斗山自然保护区珙桐种群生境空间分布格局、结构及数量特征分析,结果表明珙桐种群生境较为特殊,呈集群分布,簇生为主,在群落中地位和作用最大,种群结构稳定,多样性指数高,无天然纯林。繁殖对策以根萌蘖繁殖为主。     

伊犁自然保护区的生态价值及其开发利用刍议

伊犁地区是新疆自然保护区数量最多的地区。本文通过对伊犁地区每个自然保护区特点和生态价值的分析,提出了保护区资源开发应遵守的原则,以及开发利用的一些思路与对策。     

海南保护区旅游资源开发利用与保护

海南现有各级各类保护区７１处,总面积２．６８×１０４ｋｍ２。其类型多样,景观奇丽,具有开展多种旅游的资源优势。但是,由于受到认识、交通、通讯、环保等因素的影响,这些旅游资源远未能合理开发利用。该文分析了海南保护区的旅游资源,对其开发利用与保护提出了切实的建议。     

九岭幕阜山珍稀濒危植物资源的初步研究

论述了九岭幕阜山珍稀濒危植物的种质资源的地理分布、区系结构及其保护现状。经多年调查研究已知本区分布有第一批国家重点保护植物３２种，它们具有物种多样性、分布局限性、生态脆弱性、区系复杂性、成分特有性及起源古老性等特点。并在分析珍稀物种濒危原因的基础上，提出了珍稀濒危植物种质资源的保护对策。