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51.
为了掌握福鼎市桐江溪卤乙酸(HAAs)的含量、时空分布规律及其来源,对水体中HAAs化合物进行取样调查。根据桐江溪水文情势及沿岸特点设置10个取样点,于2017年12月及2018年7月按照涨潮、退潮情况分别对水样进行采集,检测HAAs分布情况,同时将卤乙酸(HAAs)与水质特性、涨退潮进行了相关性分析。研究发现,HAAs是普遍存在于桐江溪中的污染物质。其中,一氯乙酸(MCAA)、二氯乙酸(DCAA)、三氯乙酸(TCAA)、一溴乙酸(MBAA)、二溴乙酸(DBAA)等5种卤乙酸(HAA_5)质量浓度为0.44~3.39μg/L;一氯乙酸(MCAA)、二氯乙酸(DCAA)、三氯乙酸(TCAA)、一溴乙酸(MBAA)、二溴乙酸(DBAA)、三溴乙酸(TBAA)、一溴一氯乙酸(BCAA)、一溴二氯乙酸(BDCAA)、二溴一氯乙酸(CBDAA)等9种卤乙酸(HAA_9)质量浓度为0.83~56.15μg/L。桐江溪中HAAs主要为DCAA,TCAA,TBAA 3种,其中DCAA为制药厂及医院排水导致,主要分布在下游;TCAA主要来源于河段上游的农业生产活动;TBAA为上游沸石矿尾矿库受雨水冲刷而流入的Br~-所生成,主要分布于河流中下段。相关性分析结果表明,温度与HAA_5,HAA_9质量浓度呈现正相关,pH值与HAA_5,HAA_9质量浓度呈现负相关;TCAA质量浓度于相同季节不同潮汐及不同季节相同潮汐时均呈现上游高于下游的现象,其他HAAs均不因涨潮、退潮的差异造成质量浓度分布的变化。掌握桐江溪HAAs的含量、时空分布规律及来源,探讨其与水质的相关性,对于净水工艺选择、水厂出水HAAs含量的溯源分析、水体环境风险评估以及研究水生生物体内HAAs的累积效应等有重要意义。  相似文献   
52.
Among many techniques for generating new service ideas, morphological analysis has been used due to the advantage of decomposing the system into dimensions and shapes and bringing creative results in the process of recombining them. However, with the rise of smart service systems, the determination of dimensions and shapes has become a critical problem, particularly as both their structure and components become complex. This research focuses on a data-driven approach by incorporating mobile app service documents to increase objectivity and diversity in the construction of a morphology matrix. To this end, firstly, the novelty-quality map is developed to identify innovative data based on quantitative indicators. Secondly, morphological analysis is employed along with experts’ judgment in order to generate new smart service concepts. Finally, the feasibility and effectiveness of the proposed approach are shown based on a comparative analysis with conventional approaches and real services through a case study of smart home.  相似文献   
53.
This study investigates the connection between corporate social responsibility (CSR) and corporate reputation among the public using fuzzy set qualitative comparative analysis (fsQCA). To examine complex processes underlying the reactions of this influential stakeholder group, hypotheses are drawn from the category diagnosticity approach. Thereby, a psychological model of perceived (im)morality is transferred to the CSR context. In line with these hypotheses, positive/negative CSR activities influence reputation in the expected directions (H1a, b), while the effects of specific configurations of CSR activities reveal an asymmetry suggesting a negativity bias (H2). Further analyses confirm that positive effects require a consistent positive performance regarding prior reputations (H3a) and the aggregated CSR activities of several previous years (H3b, c). Moreover, the relevant patterns vary between industries (H4). The present study thus contributes to CSR research by investigating a powerful but hitherto understudied stakeholder group through a category diagnosticity lens combined with a configurational approach to analysis.  相似文献   
54.
Academic research (rigor) in alignment with practitioners’ challenges (relevancy) has been advocated as a way of overcoming the ivory tower syndrome. Performance measurement is at the heart of strategic management processes, as it provides a mechanism of demonstrating outcomes. Given the importance of this topic for both theory and practice, this article explores the contribution of academic outputs in terms of academic research outputs (rigor) and current practitioners’ needs (relevancy).Using network analysis and cross-citation bibliometric approaches, a sample of 1155 articles is examined and fourteen clusters are identified. The emergent topics and subtopics from the academic literature are compared to ten insights proposed by Ernst Young to the hotel sector. The findings suggest a good fit between the two approaches together with some gaps. Based from empirical results, nine propositions are articulated.  相似文献   
55.
The bioeconomy has become a central concept in many strategies for future economic development, emphasising an increasing need for collaboration across industries and sectors for innovation. This paper unpacks aspects of collaboration in the bioeconomy by looking at the development of innovation networks for biorefinery technologies from 2004 to 2014 based on innovation project data from Swedish public funding agencies using a stochastic actor-oriented model for network analysis. The analysis shows that although the network grew significantly during the time period, indicating an increasing interest in biorefinery technology innovation, inter-sectoral collaboration is not favoured over intra-sectoral collaboration. As is known from previous work on social networks trust-building is a key driver for collaboration, as actors tend to form collaborations with previous partners or indirectly connected partners, creating clustered networks.  相似文献   
56.
Vertical specialization (VS) is quantified by the VS share, which measures the average import content per dollar of exports. A characteristic of China’s export trade is its strong dependence on assembly and processing activities. To take proper account of this, China’s VS shares should explicitly distinguish processing export production from other production. We estimate China’s annual VS shares from 2000 to 2012—the latest year for which a special input–output table is available that makes such an explicit distinction. We find that VS shares increased from 2000 to 2004 and subsequently started to decrease. To explore why it has declined, we introduce a new structural decomposition approach. We find that the decrease of the VS share appears to have been driven mainly by the substitution of imported intermediates by domestic products. This occurred in particular in the production of exports, which implies an upgrading of China’s position in global value chains.  相似文献   
57.
海南岛休闲农业布局现状的实证分析   总被引:1,自引:0,他引:1  
[目的]全面分析海南岛休闲农业布局现状,为海南岛休闲农业科学合理规划和均衡协调发展提供决策参考。[方法]文章利用海南岛259家休闲农业企业的地理数据,采用比较、缓冲、密度分析工具,从数量、类型、密度、距离衰减方面实证分析海南岛休闲农业的布局特征,并提出相应的优化对策。[结果](1)海南岛东部、中部和西部休闲农业数量分布比重分别为51%、29%和20%,其中国家级示范点数量分布比重分别为83%、17%和0%;(2)休闲农业主要类型有休闲农庄、观光农园、市民农园和农家乐,除休闲农庄在东部、中部、西部分布较均匀外,其他类型分布较不均衡;(3)距离市县中心越远,休闲农业分布密度越小,95%的休闲农业分布在距离市县中心30km以内,距离市县中心10~15km是休闲农业的高峰集聚区;(4)海南岛休闲农业已在海口、保亭、三亚、澄迈、琼中、琼海、定安、儋州形成8个高度集聚带。[结论]海南岛休闲农业无论在数量、类型和密度上都是东部地区最多,中部次之,西部最少。应积极推进具有农业发展优势的地区,因地制宜拓展产业休闲功能;休闲农业产品类型单一的地区,深度挖掘特色资源和文化内涵;加强休闲农业点与旅游景区、生活服务中心之间的跨区域联系,形成和谐发展的有机旅游整体,使休闲农业真正成为农业转型、农民增收的引擎。  相似文献   
58.
[目的]从宏观、中观和微观3个层面深入分析长江经济带中三角地区湖北、湖南和江西3省的农业产业结构及其各产业差异性和相对优势及其竞争力。[方法]在宏观层面运用了传统的基尼系数分析3个省份历史发展上的地区经济水平差异,判断3个地区经济发展是否存在虹吸效应;从中观层面运用区位熵指数分析法分析区域农业产业结构,从农畜林渔等方面判断各区域产业专业化水平程度;从微观层面运用偏离—份额分析法(SSM)分离出3个地区的各部门产业的优势及其竞争力。[结果]区域内的经济差异变化呈不断增大的趋势,基尼系数不断扩大;湖北的种植业、渔业和农林牧渔服务业,湖南的种植业、林业、畜牧业和农林牧渔服务业,江西的林业、渔业都较中三角地区对应的子产业的区位熵指数高;江西木材和竹加工业和烟草业具有较大的产业竞争优势,湖北的茶叶、水产和瓜果疏菜产业优势明显,湖南地区农业产业综合优势主要在于烟草、水果、肉类以及木材和竹类加工业。[结论]通过比较地区农业产业竞争优势,提出发展地区产业特色,合理布局全域农业产业,提高农产品附加收益,稳固对结构优化的资金支持等对策建议。  相似文献   
59.
[目的]通过对全国丘陵山区县(市)与农机化有关的社会、经济和自然条件等因素进行调研所获取的238个有效样本进行分析,研究影响我国丘陵山区农机化水平的因素及其贡献,进而对我国丘陵山区进行区域划分。[方法]运用线性回归法对影响丘陵山区农机化水平的影响因素进行分析,进而对农机化水平产生显著影响的因素进行聚类分析。[结果]国内生产总值、农业劳动力数量对农机化水平产生极显著影响,耕地禀赋条件、务工工资、耕地规模、农机合作社数量和农机推广人员数量对农机化水平产生显著影响。对我国丘陵山区农机化水平呈正相关关系的因素有国内生产总值、务工工资、耕地规模、农机合作社数量,呈负相关的因素有耕地禀赋条件、农业劳动力数量、农机推广人员数量和农机化水平。[结论]我国可丘陵山区划分为中西、东南部地区,北部地区和东部沿海地区3大类地区。  相似文献   
60.
Public bike-sharing systems (BSSs) are an emerging mode of transportation introduced by municipalities to solve congestion problems in metropolitan areas, especially when integrated with other types of transportation. In the last years, the number of public bike-sharing services has been constantly on the rise all over the world, and generally the overall satisfaction with them is high. However, satisfaction with public services is driven by mechanisms that can differ from those in the private sector. It is important to establish to what extent a high satisfaction is genuine or simply ephemeral. Even “old” public services (like public transportation) become “gold” when accompanied by the introduction of new technologies. In this paper we analyze this phenomenon using data from a satisfaction web-survey conducted among customers of the public BSS “BikeMi” in Milan, Italy, in a period when mobile technologies have been introduced to speed up the service. On analyzing the responses to satisfaction questions using simple summary statistics, the level of satisfaction resulted very high. However, our aim was to look for potential “darker” sides of the service by detecting possible hidden satisfaction components. For this purpose, we used the Nonlinear Principal Components Analysis, which is particularly powerful in this context. A simple textual analysis was also performed as a validating test. Results from our analysis indicated that satisfaction is flawed by a set of factors like the mechanics of the bikes, the picking and dropping system, and the apps used to organize the service. Less concern was detected for more general aspects of the service.  相似文献   
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