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141.
当前国内外对企业组织学习和危机管理的研究都已经较为成熟,在经历了几次大的危机之后,公共危机管理引起了我国许多学者的重视,但是关于高校危机学习的研究开展并不多,而国外的学者已经先一步提出了危机学习的概念并取得一些进展。随着危机种类越来越多,发生频率越来越高,高校必须要学习掌握应对危机的方法,并以此来教育学生。然而,无论是在危机管理中还是在组织学习中,知识管理都是不可或缺的一部分。因此本文以理论研究的方式,借鉴国内外学者对危机学习中知识管理的研究,希望能对高校危机学习的更深一步探索提供思路。  相似文献   
142.
环境类高等职业教育具有鲜明的非行业背景和人才需求领域广泛而应用岗位相对集中的特殊性。在对国内部分环境类高职院校和环境类高职专业就产学研用合作机制及运行模式实地调研的基础上,对现存的环境类高职院校产学研用合作模式进行了深入分析,提出了"依托政府,实施‘双轨并行’工学结合"的产学研用合作机制与运行模式。  相似文献   
143.
Estimating influence of stocking regimes on livestock grazing distributions   总被引:1,自引:0,他引:1  
Livestock often concentrate grazing in particular regions of landscapes while partly or wholly avoiding other regions. Dispersing livestock from the heavily grazed regions is a central challenge in grazing land management. Position data gathered from GPS-collared livestock hold potential for increasing knowledge of factors driving livestock aggregation patterns, but advances in gathering the data have outpaced advancements in analyzing and learning from it. We fit a hierarchical seemingly unrelated regression (SUR) model to explore how season of stocking and the location where cattle entered a pasture influenced grazing distributions. Stocking alternated between summer on one side of the pasture one year and fall on another side of the pasture the next year for 18 years. Waypoints were recorded on cattle for 50 d each year. We focused our analysis on the pasture's 10 most heavily grazed 4-ha units, because these units were the most prone to negative grazing impacts. Though grazing of the study units was always disproportionately heavy, it was much heavier with the summer than fall stocking regime: Bayesian confidence intervals indicate summer grazing of study units was approximately double the average fall grazing value. This is our core result, and it illustrates the strong effect stocking season or date or both can have on grazing distributions. We fit three additional models to explore the relative importance of stocking season versus location. According to this analysis, stocking season played a role, but stocking location was the main driver. Ostensibly minor factors (e.g. stocking location) can greatly influence livestock distributions.  相似文献   
144.
145.
为减小船舶溢油事故应急反应人员失误概率,提升应急处置效果,在对应急人员可靠性主要影响因素识别的基础上,利用模糊贝叶斯网络(BN)建立船舶溢油应急人的可靠性分析(HRA)模型,将应急反应流程抽象为可进行概率推算的BN,实现单个应急任务和全过程人的可靠性的量化评估,并依据该模型对一起船舶溢油事故进行实例研究。结果表明,首先模糊集值专家评估较好地解决应急人员可靠性情境依赖性强,难以量化评估的问题;其次,BN卓越的概率推理性能实现由单个应急任务向全过程人的可靠性的推算;最后得到应急反应人的可靠性主要取决于关键应急任务的完成情况和相关情境因素的影响。  相似文献   
146.
为了解决利用声发射在线检测技术对储罐底板腐蚀状态进行评价时,主要依赖检测人员经验的问题,使该项技术能更好地推广和应用,利用储罐底板在线检测的声发射信息和外观检查信息,并根据相关标准及专家经验,确定与储罐底板腐蚀状态相关的表征因素。采用遗传算法(GA)改进贝叶斯网络(BN)搜索方法,建立基于GA的BN智能评价方法。针对声发射在线检测信息和外观检查信息,分别建立基于标准用声发射因素、基于声发射因素和综合考虑声发射因素和外观检查因素的基于在线检测信息的储罐底板腐蚀状态评价模型。通过对测试样本的评价,对比声发射检测专家评价结果,其中基于在线检测信息的储罐底板腐蚀状态评价模型的准确率为96%,该模型能够对储罐底板腐蚀状态进行可靠的智能评价。  相似文献   
147.
Source determination is vital in decision making and emergency planning involving hazardous chemical releases. This work was concentrated on inverse calculation approaches for source determination as well as current trends and future perspectives. In this paper, these different approaches are reviewed by dividing them into two categories: probability modeling methods and optimization modeling methods. The traits of these approaches are comparatively analyzed. Then it is shown how these approaches behave when applied to practical cases, and their feasibility, applicability, stability, and limitation in determining the location and strength are presented. It is argued that when experimenting with potential terrorist attacks involving hazardous chemical releases, observation points should be around the main line of the downwind direction when the source is known; while the uniform distribution of observation points is an efficient solution for unknown incidents. Probability modeling methods are demonstrated to be insufficient during emergency responses due to their lacking of enough prior information of unknown parameters, while optimization modeling methods are efficient and become a new trend in source determination. Findings reflect an urgent need for the development of high-accuracy detectors and further research of data transmission techniques in order to ensure the validity of these approaches.  相似文献   
148.
为探究过氧化物酶体增殖物激活受体γ/解偶联蛋白2(PPARγ/UCP2)在甲醛(FA)诱导的学习记忆障碍中的作用,本文将C57BL/6小鼠随机分为:对照组、T0070907组(抑制剂组)、3mg/m3 FA组、3mg/m3 FA+T0070907组,进行连续21d的实验暴露,在第22d取脑组织测定脑组织脏体比并匀浆,检测活性氧(ROS)、谷胱甘肽(GSH)、丙二醛(MDA)、核因子κB (NF-κB)、白细胞介素6(IL-6)、PPARγ、UCP2等生化指标,通过Nissl染色观察脑组织的病理学变化.结果发现,与对照组相比,T0070907组和3mg/m3 FA组小鼠大脑皮层神经元受损,GSH含量下降,ROS、MDA、NF-κB、IL-6含量有所上升,而3mg/m3 FA+T0070907组小鼠上述现象更严重.此外,与对照组相比,T0070907组小鼠脑组织中的PPARγ和UCP2含量下降,但3mg/m3 FA组小鼠脑组织中的PPARγ和UCP2含量上升;与3mg/m3 FA组相比,加入抑制剂的3mg/m3 FA+T0070907组小鼠脑组织中的PPARγ和UCP2含量下降.研究结果表明,在加入PPARγ抑制剂后,PPARγ/UCP2含量下降,加重了FA所致小鼠的学习记忆障碍,故PPARγ/UCP2在FA致学习记忆障碍中可能起保护作用.  相似文献   
149.
• A spectral machine learning approach is proposed for predicting mixed antibiotic. • Pretreatment is far simpler than traditional detection methods. • Performance of the model is compared in different influencing factors. • Spectral machine learning is promising in the detection of complex substances. Antibiotics are widely used in medicine and animal husbandry. However, due to the resistance of antibiotics to degradation, large amounts of antibiotics enter the environment, posing a potential risk to the ecosystem and public health. Therefore, the detection of antibiotics in the environment is necessary. Nevertheless, conventional detection methods usually involve complex pretreatment techniques and expensive instrumentation, which impose considerable time and economic costs. In this paper, we proposed a method for the fast detection of mixed antibiotics based on simplified pretreatment using spectral machine learning. With the help of a modified spectrometer, a large number of characteristic images were generated to map antibiotic information. The relationship between characteristic images and antibiotic concentrations was established by machine learning model. The coefficient of determination and root mean squared error were used to evaluate the prediction performance of the machine learning model. The results show that a well-trained machine learning model can accurately predict multiple antibiotic concentrations simultaneously with almost no pretreatment. The results from this study have some referential value for promoting the development of environmental detection technologies and digital environmental management strategies.  相似文献   
150.
为有效应对危化品事故发生与演变时存在的动态性及不确定性问题,基于事故演变过程中的关键情景状态及对应孕灾环境、应急活动和处置目标等要素,引入动态贝叶斯网络方法,构建危化品事故情景推演网络,并结合复杂网络知识,对孕灾环境和应急活动2类事故影响因素节点进行敏感性和重要度分析。结果表明:情景推演网络计算的情景节点概率符合事故发生的实际情况,能够对危化品事故在不同孕灾环境和应急救援下的演变路径进行推演,并且分析得到燃烧物、消防力量、火场环境和建筑密度等关键影响因素节点,研究结果可为事故处理提供应急辅助决策支持。  相似文献   
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