Young-boy networks without kin clusters in a lek-mating manakin

I use 10 years of data from a long-term study of lek-mating long-tailed manakins to relate the social network among males to their spatial and genetic structure. Previously, I showed that the network connectivity of young males predicts their future success. Here, I ask whether kinship might shape the organization of this “young-boy network”. Not surprisingly, males that were more socially distant (linked by longer network paths) were affiliated with perch zones (lek arenas) that were further apart. Relatedness (r) among males within the network decreased as social distance increased, as might be expected under kin selection. Nevertheless, any role for indirect inclusive fitness benefits is refuted by the slightly negative mean relatedness among males at all social distances within the network (overall mean r = −0.06). That is, relatedness ranged from slightly negative (−0.04) to more negative (−0.2). In contrast, relatedness in dyads for which at least one of the males was outside the social network (involving at least one blood-sampled male not documented to have interacted with other banded males) was slightly above the random expectation (mean r = 0.05). The slight variations around r = 0 among males of different categories likely reflect dispersal dynamics, rather than any influence of kinship on social organization. Relatedness did not covary with the age difference between males. These results, together with previous results for lack of relatedness between alpha and beta male partners, refute any role for kin selection in the evolution of cooperative display in this lek-mating system. This contribution is part of the special issue “Social Networks: new perspectives” (Guest Editors: J. Krause, D. Lusseau, and R. James).     

Social network analysis and valid Markov chain Monte Carlo tests of null models

Analyses of animal social networks derived from group-based associations often rely on randomisation methods developed in ecology (Manly, Ecology 76:1109–1115, 1995) and made available to the animal behaviour community through implementation of a pair-wise swapping algorithm by Bejder et al. (Anim Behav 56:719–725, 1998). We report a correctable flaw in this method and point the reader to a wider literature on the subject of null models in the ecology literature. We illustrate the importance of correcting the method using a toy network and use it to make a preliminary analysis of a network of associations among eagle rays.

长江三角洲河网地区典型城镇街尘中多环芳烃的污染特征

街尘是一种重要的环境介质,其携带的污染物在城镇化过程中对河网地区的水环境构成了一定的威胁.为初步探讨长江三角洲河网地区典型街尘中多环芳烃(PAHs)的污染特征,以杭嘉湖平原河网地区饮用水水源河流上游典型小城镇的街尘为研究对象,对工业区、交通干道、旧居区、新居区和商业区5种土地利用类型的15个采样点进行街尘样品采集和粒径分级,测试街尘的密度、有机质含量以及16种U.S.EPA优控PAHs含量等指标.结果表明,粒径为<63、63～125、125～250和250～900μm街尘中总多环芳烃(∑PAHs)的平均含量分别为7261、5835、4660和2909μg·kg-1,粒径越小,PAHs含量越高,其生态风险越大.不同土地利用类型的街尘中PAHs的含量顺序依次为:工业区>交通干道>旧居区>新居区>商业区.街尘中PAHs和有机质含量存在显著正相关关系,且街尘粒径越小,有机质和PAHs的相关性越强.源解析结果表明,街尘中的PAHs多为燃烧源.     

基于遗传神经网络的化工企业安全评价

基于化工企业特点,建立了比较合理的安全评价指标结构,并构建了以遗传神经网络为基础的评价模型。通过建立训练样本,确定BP神经网络的网络结构,运用遗传算法（GA ）去优化BP网络的初始权值和阈值,再把优化之后的权值和阈值赋给BP神经网络,然后对其进行训练,训练完毕后将所建立的模型通过实例评价进行了验证,结果表明此模型在化工企业安全评价中具有较好的应用价值。     

基于物联网林区火险监警系统方案的探讨

利用传感技术、卫星定位、地理信息、人工智能等物联网相关技术,设计适用于城市森林、自然保护区、旅游景区等环境防火监测系统,系统可对监测区域环境因素尤其火情信息实现区域覆盖、全天候、数字化监测,构建起数字化森林物联网络,可为森林防火提供实时、准确、科学的依据。     

兴安落叶松林地表可燃物含水率预测模型的研建

对大兴安岭落叶松林地表可燃物含水率影响因子进行分析,选取主要的环境因子,为该区域内林火管理工作提供重要的理论依据。利用软件SPSS Clementine12.0,将相对湿度、地表温度、空气温度作为输入神经元,将兴安落叶松林地表可燃物含水率作为神经网络输出神经元,建立基于BP神经网络的含水率模型。应用BP神经网络模型敏感度分析结果来评定环境因子对兴安落叶松林地表可燃物含水率影响的大小,分析表明,影响兴安落叶松林地表可燃物含水率的主要环境因子由小到大排序为:相对湿度、地表温度、空气温度。构建的兴安落叶松林地表可燃物含水率BP神经网络模型对该区域内的林火管理工作具有一定的借鉴意义。     

矿井通风三维仿真系统及其应用研究

介绍了矿井通风三维仿真系统的原理及特色,阐述了模拟矿井通风整体网络所需要的调研内容。结合某大型矿山矿井通风系统实例,针对其矿井总风量不足、大型机械化作业盘区环境恶劣、自然风压影响大、通风构筑物不完善等问题,拟定了三个技术方案,并通过矿井通风三维仿真系统进行模拟分析,展示了矿井通风系统三维仿真、方案优选、空气幕选型、自然风压等模拟原理和过程。最后,通过模拟确定的矿井通风系统最优技术方案实施后,其现场测定数据与模拟数据基本吻合,证明了系统的可靠性,改善了井下通风效果,保证了矿井安全高效的生产工作。     

基于GA与最长路径并联通路法优化通风网络图绘制

针对矿井通风网络图分支交叉的问题,基于最长路径对网络图节点分层,以遗传算法优化节点排序,主要采用堆积木的组合思想来进行层间交叉与层内交叉操作,提高层次图的质量（减少分支交叉数）,并以重心定位启发式算法来增强遗传算法的局部搜索能力,提高遗传算法的搜索质量。最后,以改进的最长路径并联通路法绘制出较优的通风网络图。     

金属矿井热害评价体系与评价方法

为减小金属矿井热害对井下人员安全及井下开采工作的不利影响,需对井下热害进行评价和预测。基于文献调查和专家评价方法,结合工程实际,利用层次分析法构建金属矿井采矿热害评价体系,从生产能力、地质条件、矿井通风、地理环境四个方面提出17个评价指标。在分析层次分析法（AHP）确定权重不足的基础上,结合物元分析理论,建立确定金属矿井热害评价各因素权重的物元分析模型。在各评价因素权重确定的基础上,以BP神经网络作为评价工具,构建金属矿井热害综合评价预测模型。最后,以某矿山为例,进行评价和预测分析。结果表明,基于物元分析和AHP的BP深井网络评价模型预测误差最大只有3%。     

基于ANP的煤矿员工非意向不安全行为影响因素研究

为量化分析非意向不安全行为的影响因素,基于专家判断法和网络层次分析法（ANP）,运用超级决策（SD）软件分析评价了30个因素对非意向不安全行为的影响。结果表明:对国有大中型煤炭企业而言,个体特征、组织及任务、机械设备对非意向不安全行为有很大的影响,环境因素对非意向不安全行为影响权重相对较小;应急反应、应急演练、信息传递、注意力、监督反馈、安全警示、工作经验、应急设施、作业规范、疲劳程度等10个因素是企业干预、控制非意向不安全行为的重点关注因素。