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关键词： Multi-layer aquifer   Longscreen boreholes   Machine learning   Random Forest   Hydrogeochemistry   Hydrogeology  

摘要： Accurate identification of the origin of groundwater samples is not always possible in complex multilayered aquifers. This poses a major difficulty for a reliable interpretation of geochemical results. The problem is especially severe when the information on the tubewells design is hard to obtain. This paper shows a supervised classification method based on the Random Forest (RF) machine learning technique to identify the layer from where groundwater samples were extracted. The classification rules were based on the major ion composition of the samples. We applied this method to the Campo de Cartagena multi-layer aquifer system, in southeastern Spain. A large amount of hydrogeochemical data was available, but only a limited fraction of the sampled tubewells included a reliable determination of the borehole design and, consequently, of the aquifer layer being exploited. Added difficulty was the very similar compositions of water samples extracted from different aquifer layers. Moreover, not all groundwater samples included the same geochemical variables. Despite of the difficulty of such a background, the Random Forest classification reached accuracies over 90%. These results were much better than the Linear Discriminant Analysis (LDA) and Decision Trees (CART) supervised classification methods. From a total of 1549 samples, 805 proceeded from one unique identified aquifer, 409 proceeded from a possible blend of waters from several aquifers and 335 were of unknown origin. Only 468 of the 805 unique-aquifer samples included all the chemical variables needed to calibrate and validate the models. Finally, 107 of the groundwater samples of unknown origin could be classified. Most unclassified samples did not feature a complete dataset. The uncertainty on the identification of training samples was taken in account to enhance the model. Most of the samples that could not be identified had an incomplete dataset. (C) 2013 Elsevier B.V. All rights reserved.

关键词： ALKYLBENZENES  

摘要： The article discusses the Labix joint venture between chemical firms Thai Oil subsidiary Thai Paraxylene (TPX) and Mitsui & Co. for a linear alkylbenzene (LAB) production refinery in Sriracha, Thailand, noting that Hyundai was awarded the project engineering, procurement, and construction contract.

关键词： foci commitment   justice   public university   teacher   trust  

摘要： In public university setting, whether trust in supervisor would attenuate the relationship justice and commitment is not certain. In addition, past commitment research focused on organizational commitment, but neglected the foci of commitment. This study investigated the moderating role of trust in supervisor in the relation of distributive justice, procedural justice, and interactional justice with foci commitment (commitment to school, commitment to supervisor, and commitment to colleagues). It was expected that the relationships between three types of justice and foci commitment were weaker for those with high trust in their supervisor. This study uses teachers in public universities as the research sample, collects data by questionnaire survey, and analyzes data through hierarchical moderator regression. This study finds that whether trust in supervisor has the attenuating effect for the influence of justice on commitment depends on the type of justice and commitment. Trust in supervisor can attenuate all relationships between three types of justice and commitment to supervisor. However, regarding commitment to colleagues, trust in supervisor can only attenuate the effect of distributive justice on it.

关键词： 金相分析   刀剪   应用   显微组织   失效分析  

摘要： 本文简要介绍了金相分析对刀剪产品检验的作用，然后对这种检验方法分别在刀具、剪刀产品检验以及刀具失效分析中的应用做了具体的案例分析。

关键词： 传感器   监理   应用  

摘要： 本文结合作者的设备工程监理检验实践,概括阐述了传感器在监理检验行业的应用及作用。

关键词： 计价货币   新开放经济宏观经济学   局部均衡   一般均衡   微观基础  

摘要： 国际贸易中计价货币选择决定因素的研究,多基于新开放经济宏观经济学理论,着眼于计价货币选择的微观基础,以厂商预期利润最大化为目标,采用局部均衡或一般均衡分析法展开论证。既有文献认为,贸易双方影响市场的能力、金融市场的健康完善程度是影响计价货币选择的主要因素。但这些研究在理论假设、研究视野、实证检验及覆盖面等方面仍有缺憾,对发展中国家尤其对中国的情况缺乏深入探讨,亟须后续研究重点突破。

关键词： 检察技术工作   执法办案   同步录音录像   文件检验   电子数据   司法会计   服务   侦查人员  

摘要： 检察技术工作是检察工作的重要组成部分,当前,随着信息技术在社会生活中的广泛应用,修改后刑诉法、民诉法的实施以及其他相关法律、法规的进一步完善,检察技术的重要作用越来越显现。如何进一步发挥检察技术的作用,更好地为办案服务,是我们技术工作永恒的主题。一、文检技术在办理案件中所发挥的作用一是运用文检技术手段帮助侦查人员确定犯罪事实或犯罪嫌疑人,为侦查提供方向。

关键词： 消费者信心指数   居民消费   Carroll两步处理法   方向分析  

摘要： 文章基于2001-2011年的季度数据,采用Carroll两步处理法和非参数方向分析分别检验我国消费者信心指数对居民消费的预测作用及其有效性,结果表明:(1)控制变量为可支配收入或历史消费时,消费者信心指数及其分指数对居民总消费和衣着、居住、杂项商品与服务分项消费的变动存在解释能力,对食品、家庭设备用品及服务分项消费几乎无解释能力,对其他分项消费的解释能力随控制变量的不同而不同;(2)消费者信心指数及其分指数可有效预测居民总消费、杂项商品及服务消费等的变动。

关键词： 临床   医学检验   地位和作用  

摘要： 医学检验在临床中十分重要,是确诊疾病、进行治疗的关键所在。本文从临床生物化学检验和微生物学两个方面进行探析其地位和作用,并提出临床和医学检验想结合的措施。

关键词： 质量安全管理   检验科   安全管理体系   检验技术   临床医学   医学检验   医疗服务   临床检验  

摘要： 随着检验技术的迅速发展,医学检验已成为临床医学的重要组成部分,在疾病的诊治中起着举足轻重的作用。为更好的发挥临床检验在医疗服务中的作用,检验质量安全管理体系的构建和完善显得尤为重要[1-2]。本科自成立质量安全管理团队以来,工作中取得了较好的效果,现将质量安全管理团队在检验科日常工作中的作用及其体会报道如下。