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391.
解决空气雾化钻井井眼净化问题,试验架是关键装置、基础设备和必要手段。对空气雾化钻井试验架的研制过程进行了深入剖析,介绍了在试验架研制中应遵循的一些基本原则,试验架基本结构,试验架主要参数,试验结果可靠性分析,试验研究进行情况,以及研制过程中的经验教训等内容,体现了空气雾化钻井试验架研制工作的特点与特色。 相似文献
392.
蔡海霞 《北京理工大学学报(社会科学版)》2016,18(4):9-18
基于多维效应的能源效率评估使人们在达到经济增长目的的同时兼顾能源安全、竞争力、环境、社会和技术的可持续性。论述能源效率内涵演化发展的路径,在此基础上将能源效率的内涵扩展至多维效应。以非参数DEA(Data Envelopment Analysis)方法为例,研究基于多维效应的能源效率评估方法的演化与发展趋势。研究结果显示:采用DEA方法对基于多维效应的能源效率进行评估的发展趋势主要有以下3点:能源效率的内涵不断延伸;DEA模型向非导向非径向模型转变;能源效率评估的研究维度不断扩展。对多维效应的能源效率综合指标评价体系和评价方法还需做深入研究。 相似文献
393.
ABSTRACTWe consider the case of production units arranged into a number of groups. All units within a group choose output–input combinations from the same production possibilities set that is represented by a stochastic frontier model. The metafrontier is the envelope of the group-specific frontiers. We are interested in the metafrontier distance, which is the amount by which the group-specific frontier lies below the metafrontier.Previous work has measured the metafrontier distance using the deterministic portion of the frontier. In a stochastic frontier model, this is not appropriate. We show how to evaluate the metafrontier distance, and we demonstrate the empirical relevance of this issue. 相似文献
394.
This article examines how childhood innocence is taken up in (92) memories of undergraduate students across four sites in the US and Canada. Drawing from Foucault's theory of discourse, we examine how three themes—innocence as not knowing, innocence as being provided for, and loss of innocence as exposure to adversity—construct childhood as the absence of conflict, which perpetuates the myth of an innocence/experience binary and encourages a deficit perspective of childhood. These findings contribute to teacher education and childhood studies by highlighting the importance of interrogating adult memories in order to disrupt normative assumptions about children. 相似文献
395.
A framework for assessing photographs for the emotional and social health of young people (SHAPE) is described and tested, within the context of a rural program. Two independent raters assessed the photographs of participants. To assess inter-rater reliability, Cohen’ K and Kendall’s W were calculated. The two reviewers’ assessments of photographs were in agreement. The assessment of emotional/behavioural display showed 82% agreement. Agreement between reviewers’ judgements of proxemics (W = .866), interaction (W = .722), engagement (W = .932) and overall impression (W = .804) were all significant (p < .005). The method yielded results indicating that participants found gardening immediately engaging but their approach to equines exhibited a change from fascination to confidence during the program. The visual-diary method is a useful and sensitive method for research: where resources are limited; to complement traditional measures; for use with people who lack appropriate verbal communication or literacy skills to complete questionnaires; young children; other underrepresented groups. 相似文献
396.
Yuzhu Tian Liyong Wang Maozai Tian 《Journal of Statistical Computation and Simulation》2019,89(15):2951-2979
Bridge penalized regression has many desirable statistical properties such as unbiasedness, sparseness as well as ‘oracle’. In Bayesian framework, bridge regularized penalty can be implemented based on generalized Gaussian distribution (GGD) prior. In this paper, we incorporate Bayesian bridge-randomized penalty and its adaptive version into the quantile regression (QR) models with autoregressive perturbations to conduct Bayesian penalization estimation. Employing the working likelihood of the asymmetric Laplace distribution (ALD) perturbations, the Bayesian joint hierarchical models are established. Based on the mixture representations of the ALD and generalized Gaussian distribution (GGD) priors of coefficients, the hybrid algorithms based on Gibbs sampler and Metropolis-Hasting sampler are provided to conduct fully Bayesian posterior estimation. Finally, the proposed Bayesian procedures are illustrated by some simulation examples and applied to a real data application of the electricity consumption. 相似文献
397.
《Omega》2017
One of the major challenges for the implementation of local energy planning is the successful development of a Sustainable Energy Action Plan (SEAP) by the local authorities (especially within the framework of their participation to the Covenant of Mayors’ initiative). This aspect constitutes a decision making problem, since the local authorities have to identify the best fields of actions and opportunities for reaching their long-term CO2 reduction target. However, the already available methods and tools do not offer an integrated framework for the SEAPs’ development and especially the selection of sustainable Renewable Energy Sources (RES) and Rational Use of Energy (RUE) technologies. In this context, the aim of this paper is to present a participatory supportive framework for the implementation of local energy planning. At the first level, the proposed approach incorporates the development of alternative Scenarios of Actions (using knowledge-based process, participatory approach and aspiration level). At the second level, a direct and transparent multicriteria decision support is introduced, in order to evaluate the feasible Scenarios. It includes the application of a multicriteria ordinal regression approach and an extreme ranking analysis method for the estimation of the best and worst possible ranking position of each Scenario. The results from the pilot appraisal of the methodological approach to a “real” problem are presented and discussed. The adopted approach contributes to the selection of the most appropriate combination of RES/RUE actions, supporting in this way the local authorities to the development of their SEAP. 相似文献
398.
399.
旅游交通是旅游经济发展中重要的内容之一,通过对中国十大城市群城市旅游交通可达性、铁路交通流分布情况与旅游经济联系、总量和隶属度进行计算,借助Arcgis10.2对中国十大城市群交通空间流分布情况和旅游经济联系进行空间可视化处理,并对计算结果进行综合比较分析。研究发现:高铁使得中国十大城市群城市旅游交通可达性水平得到大幅提升,且交通流分布均衡。中国十大城市群城市可达性的提升给城市旅游经济带来了一定的积极影响。高铁网络下中国十大城市群旅游经济联系分布不均衡。 相似文献
400.
王大伟 《吉林工程技术师范学院学报》2014,(3):67-68
目前企业都在信息化,网络是企业必不可少的.而网络设备的部署则是一切的开端,只有将宽泛合理应用才能搭建一个良好的网络环境.目前网络设备部署大多采用多层交换网络.网络设备的选择必须根据实际做出适当的调整,以实际情况为最优先考虑,才能为企业设计出最合适的智能网络. 相似文献