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The complexity and spatial heterogeneity of ecosystem processes driving ecosystem service delivery require spatially explicit models that take into account the different parameters affecting those processes. Current attempts to model ecosystem service delivery on a broad, regional scale often depend on indicator-based approaches that are generally not able to fully capture the complexity of ecosystem processes. Moreover, they do not allow quantification of uncertainty on their predictions. In this paper, we discuss a QGIS plug-in which promotes the use of Bayesian belief networks for regional modelling and mapping of ecosystem service delivery and associated uncertainties. Different types of specific Bayesian belief network output maps, delivered by the plug-in, are discussed and their decision support capacities are evaluated. This plug-in, used in combination with firmly developed Bayesian belief networks, has the potential to add value to current spatial ecosystem service accounting methods. The plug-in can also be used in other research domains dealing with spatial data and uncertainty. 相似文献
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Changes in a population of rainbow smelt (Osmerus mordax) in the Apostle Islands region of Lake Superior were chronicled over a 32-yr time series, 1974-2005. At the beginning of the time series, rainbow smelt was the predominant prey species, abundance of lake herring (Coregonis artedi) was very low, and the dominant predator was stocked lake trout (Salvelinus namaycush). Following a period of successful lake trout stocking in the 1970s, the rainbow smelt population declined sharply in 1980, largely through mortality of adult fish and subsequent poor recruitment. In the succeeding 4 years, rainbow smelt populations reached historic low levels, resulting in reduced food resources for both wild and stocked lake trout. During 1985–1990 lake herring stocks began a spectacular recovery following the appearance of a very strong 1984 year class and subsequent 1988, 1989, and 1990 year classes. Rainbow smelt benefited from the high abundance of young lake herring as an alternate prey source for lake trout and showed a partial recovery in the late 1980s. However, a growing lake trout population coupled with an 8-yr period of low herring reproduction after 1990 resulted in a diminished rainbow smelt population dominated by age-1 and 2 fish and showing a pattern of alternating recruitment attributed to cannibalism. Low productivity of rainbow smelt and intermittent production of herring over the past decade has left lake trout populations with a diminished prey base. Although lake trout recovery benefited from the presence of rainbow smelt as a prey resource, the Lake Superior fish community was fundamentally altered by the introduction of rainbow smelt. 相似文献
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车型识别具有广阔的应用前景,BP神经网络在车型识别中能够提高车型的识别率。在任何车型大致都可以抽象成一个"工"字型情况下,提取其中的顶长比、前后比和顶高比这三项相对参数作为BP神经网络的输入参数。采用三层3-8-3的BP神经网络,并用14对输入参数离线训练,再用4对新数据进行检验,均得到了预想的期望值。 相似文献
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Managing sports performance is very important in the sports industry. Performance, the executives, centers on boosting competitor execution and decreasing the danger of injury. Several factors contribute to these goals, including player health, emotional status, exercise load and physical intensity requirements. Generally speaking, injury prediction is an essential component of injury prevention, and successful identification of injury prediction is a primary indicator for effective prevention. The proposed Artificial Neural Network (ANN) objective is to develop and use early-doing ability and exercise load data to validate a hierarchical machine learning prediction system with accurate detection of player injuries. The physical and workload that requires detection of this early personalized damage can be avoided with specific help. The framework is used to test 21 soccer players’ sports information from various sources, including gathered and inside burden information, outside burden information, and review information. The entirety of this information is fused into the proposed framework to improve the exactness of harm expectation. This calculation distinguishes competitors in danger of injury, with their early intervention available. 相似文献
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校园规模在不断地扩大,校园房屋管理规划部门对日益更新和迅速增加的建筑物房屋信息的管理与维护愈感困难,而现有的系统对空间数据与属性数据没有很好集成,更不利于图文信息的相互查询、检索和更新等。针对如上现实问题,应用MapInfo平台中的WebGIS技术,即MapXtreme技术,以及UML统一建模技术和SQL Server数据库等技术,成功地实现了数字校园房屋管理系统设计与开发,解决了房管部门面临的查询搜索更新校园建筑房屋信息时效率低下、管理与维护困难等实际问题。 相似文献
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传统多路通信电源欠压锁定电路存在结构复杂、响应速度差等缺陷。为精准控制多路通信电源欠压锁定电路,需设计一种新型多路通信电源欠压锁定电路,并采用数字控制方法控制多路通信电源欠压锁定电路。采用电流模控制技术,通过随电源电压呈现二次方曲线变化的自偏置电流调节新型多路通信电源欠压锁定电路上、下阈值门限电压,控制迟滞电压,改善电路响应速度;同时通过温度补偿方式降低新型电路基准电压温度敏感系数,使迟滞电压温度灵敏度较低,迟滞电压具有较高的稳定性和较小的漂移程度。经过实验分析发现,该方法控制下的多路通信电源欠压锁定电路电源电压在1.65 V/μs时,输出电压上升和下降时间是36 ns,控制电路能量消耗平均值为51.684μW,电路响应速度较快,能耗低。 相似文献