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981.
The safety climate of an organization is considered a leading indicator of potential risk for railway organizations. This study adopts the perceptual measurement–individual attribute approach to investigate the safety climate of a railway organization. The railway safety climate attributes are evaluated from the perspective of railway system staff. We identify four safety climate dimensions from exploratory factor analysis, namely safety communication, safety training, safety management and subjectively evaluated safety performance. Analytical results indicate that the safety climate differs at vertical and horizontal organizational levels. This study contributes to the literature by providing empirical evidence of the multilevel safety climate in a railway organization, presents possible causes of the differences under various cultural contexts and differentiates between safety climate scales for diverse workgroups within the railway organization. This information can be used to improve the safety sustainability of railway organizations and to conduct safety supervisions for the government.  相似文献   
982.
臭氧是城市光化学烟雾的主要成分,同时也是重要的温室气体,因此臭氧污染已经成为城市空气质量的重要因素.对重庆市渝中区2015年3个空气质量自动监测点臭氧浓度进行比较,并分析了臭氧与环境、日照、气温、挥发性有机物、NO2、PM10、PM2.5的相关性.结果表明:臭氧浓度与监测点周围环境有关;臭氧浓度呈典型的季节变化趋势,与日照、气温呈明显的正相关;臭氧浓度小时值变化出现明显的日变化规律;臭氧浓度与挥发性有机物呈正相关,与NO2、PM10、PM2.5有较好的负相关性.  相似文献   
983.
基于地域性的三种污泥干化工艺的经济性比较   总被引:2,自引:2,他引:0       下载免费PDF全文
随着城市污水排放量的增多和成分的复杂化,污泥处理已成为污水处理厂面临的最大难题。脱水污泥含水率高,不利于后续的处理与再利用。污泥热干化可将污泥含水率降至10%~40%,但该过程耗能大,会大幅增加污泥处理成本,不利于污泥处理技术的推广应用。以拉萨、上海、重庆为例,分别对带式干化、热泵-太阳能干化、热泵-太阳能-蓄热干化3种污泥干化工艺的经济性进行分析,阐明了不同干化方式的适用特点,为相变蓄热技术在污泥干化中的推广应用提供了技术参考。  相似文献   
984.
高华中 《地球与环境》2016,44(6):595-599
地球化学元素比值的变化不仅可以指示气候变化和环境特征,也可以揭示气候异常和突变性气候事件。本文通过对沂沭河流域沭埠岭剖面沉积物淋溶系数、残积系数、CaO/MgO、硅铝率、硅铝铁率等气候代用指标的分析,发现研究区7 470~2550 a BP期间的气候变化经历了五个阶段:(1)7 472~6 043 a BP,气候趋向温暖湿润;(2)6 043~4 801 a BP,稳定的暖湿时期;(3)4 801~3 986 a BP,气候向冷干转变;(4)3 986~3 512 a BP,不稳定时期;(5)3 512~2 552 a BP,气候不稳定的波动时期。  相似文献   
985.
运用相关分析、因子分析、富集因子和HYSPLIT模型对石羊河流域从2013年7月到2014年7月连续收集降水样品的主要离子浓度特征及来源进行了探讨分析,结果表明,Ca~(2+)和Na~+是主要的阳离子,SO_4~(2-)和NO_3~-是主要的阴离子,石羊河流域的主要降水类型为SO_4~(2-)-NO_3~--Ca~(2+);石羊河流域的总离子浓度的季节大小变化顺序为冬季春季秋季夏季,石羊河流域的降水水化学主要受地壳源和人为源的影响;石羊河流域的降水类型分为季风降水、西风降水和混合降水,而混合降水是石羊河流域的主要降水类型,其次为西风降水,最后为季风降水。  相似文献   
986.
On 1 June 2017, the US President Donald Trump officially announced the withdrawal from the Paris Agreement, thus the study on the reasons of withdrawal, the potential impacts, and coping strategies has become a focus among policy circles and of the international community. Based on the self-developed US Policy Assessment Model, this paper systematically evaluates the three potential “major deficits” in terms of mitigation, climate finance, and global climate governance, as a result of the US withdrawal from the Paris Agreement and puts forward policy suggestions for coping with such transformations accordingly. The study shows that the United States ’withdrawal from the Paris Agreement will affect the existence and implementation of successive climate policies and result in an additional 8.8–13.4% increase in the global emissions reduction deficit. The United States’ withdrawal will also deteriorate the existing climate finance mechanism. The Green Climate Fund (GCF)’s funding gap will increase by US$2 billion, while the gap of long-term climate finance will increase by about US$5 billion a year. Either the China–EU or the “BASIC plus” mechanism could fill the governance deficit caused by the United States and the lack of political momentum may continue for a while in the future.  相似文献   
987.
Carbon labels are innovative medium and tools for climate change communication and low-carbon marketing. This study aims at examining how college students are aware of low-carbon and carbon labels, whether they are more willing to communicate low-carbon ideas, and also the determinants affecting their interpersonal communication of carbon labels. The multiple regression analysis shows that Chinese college students’ willingness of interpersonal communication of carbon labels are significantly influenced by their awareness of climate change crisis, the perceived value of carbon labels, the consideration of product environmental attributes, the preferences of carbon labels, the household background, and their educational background. In response to these factors, this paper proposes, in a public perspective, the strategies to enhance the dissemination of carbon labels.  相似文献   
988.
Abstract: Populations at the margin of geographic ranges of distribution have been considered more vulnerable than central ones, but recent reviews have caste doubt on this generalization. We examined the reproductive and demographic performance of a rare Euroasiatic orchid (Cypripedium calceolus) at its southwesterly range limit and compared our findings with those of previous studies of nine central populations at the center of the orchid's range. We sought to test the central‐marginal model and to evaluate factors involved in long‐term performance of forest Eurosiberian species with peripheral populations in southern European mountains. We characterized (structure, temporal fluctuations, herbivory, reproductive success, and recruitment at different habitats) four Pyrenean populations of C. calceolus of different sizes (5–3500 ramets) and monitored three of them for up to 13 years. Two quantitative stochastic models (count data and matrix models) were used to assess population trends and viability and the effect of herbivory. Contrary to expectations, and despite the negative effect of sporadic events of herbivory, the peripheral populations we studied (except the smallest one) performed similarly or better than populations occurring in central part of the species’ range in terms of reproductive success and population growth rates. Landscape changes over the last 50 years suggest that natural reforestation could be involved in the success of this plant at its southern limit. Forest expansion in the mountain regions of southern Europe may provide new opportunities for plants with geographic distributions centered mainly at higher latitudes and give some hope for their recovery in future scenarios dominated by biodiversity loss.  相似文献   
989.
Parks, waterways, and vegetation enhance the well-being of urbanites and thus warrant consideration in planning and policy-making. It is, however, difficult to assess how land-use change may impact these features and how this in turn may impact well-being. I use a case-study approach to present a framework that combines geospatial and economic valuation techniques to generate indicators of the effects of land-use policies that alter these amenities on community well-being. This framework quantifies the impacts of land-use change on urban environmental amenities in a way that could help communities plan land use so as to maintain well-being as they urbanise.  相似文献   
990.
RaMCo is a prototype version of a decision-support system for coastal-zone management. The model is based on the findings of a multidisiciplinary research program, conducted in Southwest Sulawesi, Indonesia. Different management strategies can be compared on the basis of the short- and long-term consequences. Land-use change has been included in RaMCo in view of the impacts of land-based human activities on the marine environment. The key aspect of the model is a combination of the temporal dynamics of land-use change on the regional (macro-level) scale and spatial dynamics on the local (micro-level) scale. Constrained cellular automata are used to integrate both scale levels. The state changes of the cells depend on the consistency with the macro-scale model, local geographical conditions, and interaction with neighboring cells. In this paper, we discuss the underlying theoretical assumptions of the macro-scale and micro-scale models, some characteristic results for land-use change in the study area, and the validation problem.  相似文献   
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