双光谱卫星云图的模糊推理云分类

基于观测事实和分类经验,在对卫星云图上云系形态特征定性分析的基础上,采用模糊推理方法,提取出云类识别的诊断判别因子和模糊推理规则。通过对判别因子的模糊化处理和隶属度函数的调制优化,建立了卫星云图定量化的模糊推理云分类模型。4种常见云系的模糊推理分类试验结果表明,模糊推理方法在定量性、客观性和自动化等方面优于传统卫星云图目视判读方法,在卫星遥感资料的分析处理和天气预报等领域有较好的实用意义。     

Evolutionary diversity and spatiotemporal dynamics of a spatial game

In this paper, the evolution of cooperation is studied by a spatially structured evolutionary game model in which the players are located on a two-dimensional square lattice. Each player can choose one of the following strategies: “always defect” (ALLD), “tit-for-tat” (TFT), and “always cooperate” (ALLC). Players merely interact with four immediate neighbors at first and adjust strategies according to their rewards. First, the evolutionary dynamics of the three strategies in non-spatial population is investigated, and the results indicate that cooperation is not favored in most settings without spatial structure. Next, an analytical method, which is based on comparing the local payoff structures, is introduced for the spatial game model. Using the conditions derived from the method as criteria, the parameter plane for two major parameters of the spatial game model is divided and nine representative regions are identified. In each parameter region, a distinct spatiotemporal dynamics is characterized. The spatiotemporal dynamics not only verify that the spatial structure promote the evolution of cooperation but also reveal how cooperation is favored. Our results show that spatial structure is the keystone of the evolution of intraspecific diversity.     

A counterfactual approach to measure the impact of wet grassland conservation on U.K. breeding bird populations

Wet grassland populations of wading birds in the United Kingdom have declined severely since 1990. To help mitigate these declines, the Royal Society for the Protection of Birds has restored and managed lowland wet grassland nature reserves to benefit these and other species. However, the impact of these reserves on bird population trends has not been evaluated experimentally due to a lack of control populations. We compared population trends from 1994 to 2018 among 5 bird species of conservation concern that breed on these nature reserves with counterfactual trends created from matched breeding bird survey observations. We compared reserve trends with 3 different counterfactuals based on different scenarios of how reserve populations could have developed in the absence of conservation. Effects of conservation interventions were positive for all 4 targeted wading bird species: Lapwing (Vanellus vanellus), Redshank (Tringa totanus), Curlew (Numenius arquata), and Snipe (Gallinago gallinago). There was no positive effect of conservation interventions on reserves for the passerine, Yellow Wagtail (Motacilla flava). Our approach using monitoring data to produce valid counterfactual controls is a broadly applicable method allowing large-scale evaluation of conservation impact.     

基于演化博弈的危化品安全监管情景推演研究

针对危化品安全生产监管问题,基于演化博弈理论构建危化品安全监管演化博弈模型,并将危化品事故发生率引入模型,对比分析危化品企业与地方政府监管部门行为策略的演化稳定均衡。在此基础上进行情景推演模拟仿真,研究表明:危化品事故发生率,对危化品企业和地方政府监管部门的策略选择有显著影响,当危化品事故发生概率低于某一临界值时,危化品企业和监管部门都会疏忽安全投入和监管;地方政府承受危化品事故经济损失和信誉损失增大时,危化品安全监管系统演化呈现出周期性波动;引入上级政府惩罚机制情景下,当上级政府惩罚力度高于危化品企业未投入安全生产受到的处罚和地方政府安全监管成本时,其最终都选择安全投入和严格监管策略。研究结论为政府监管危化品安全生产提供新的思路和对策建议。     

玛纳斯河水质参数时空变化规律浅析

玛纳斯河近5年水质监测结果统计分析表明,玛纳斯河水质良好,平常各监测项目均不超标。在汛期,因泥沙及有机质的影响,SS超标,高锰酸盐指数也有部分超标。上述2参数年际变化亦较大,且有逐年上升趋势。     

面向复杂设备的分布式故障诊断研究

基于复杂系统的设备故障诊断的要求 ,按故障信息流动的方向将诊断过程分为实时监测层、故障诊断层及综合决策层 ,并建造一种分布式多级黑板诊断结构模型。根据不同诊断层次的特点 ,赋予其不同的诊断方法。在实时监测层中各实时监测单元采用神经网络和知识基模块的混合结构完成该层任务 ;故障诊断层则基于广义知识表达模型 ,建立三库结构 ,即静态实例库、动态实例库和规则库 ,整个推理过程基于三级推理机制 ;综合决策层为一智能型的辅助决策支持系统 ,提供对整个系统生产与设备运行状态的综合诊断与决策。     

A neuro-fuzzy algorithm for assessment of health,safety, environment and ergonomics in a large petrochemical plant

Process plants such as petrochemical units have been continuously trying to improve Health, Safety, Environment and Ergonomics (HSEE) programs. This study proposes an adaptive network-based fuzzy inference system (ANFIS) for assessment of HSEE programs in a petrochemical plant. The proposed neuro-fuzzy approach is applied to a set of operators in the petrochemical unit to show its applicability and superiority. To achieve the objectives of this study, standard questionnaires with respect to HSEE are completed by operators. The average results for each category of HSEE are used as inputs and accomplishment of HSEE programs is used as output for the algorithm. Moreover, this algorithm is used to rank operators performance with respect to HSEE. Finally, the algorithm identifies efficient operators with respect to HSEE. This is the first study that introduces an intelligence algorithm for assessment and improvement of HSEE program in a petrochemical plant.     

水质模型参数识别的遗传算法

Ｏ’ｃｏｎｎｏｒ模型是一个比广泛应用的Ｓｔｒｅｅｔｅｒ－Ｐｈｉｌｉｐｓ模型更精确的水质模型,由于该模型参数率定的困难性,限制它在实际中应用。     

Asymptotics in adaptive cluster sampling

In this article we consider asymptotic properties of the Horvitz-Thompson and Hansen-Hurwitz types of estimators under the adaptive cluster sampling variants obtained by selecting the initial sample by simple random sampling without replacement and by unequal probability sampling with replacement. We develop an asymptotic framework, which basically assumes that the number of units in the initial sample, as well as the number of units and networks in the population tend to infinity, but that the network sizes are bounded. Using this framework we prove that under each of the two variants of adaptive sampling above mentioned, both the Horvitz-Thompson and Hansen-Hurwitz types of estimators are design-consistent and asymptotically normally distributed. In addition we show that the ordinary estimators of their variances are also design-consistent estimators.