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251.
Tracking spatial and temporal trends of events (e.g. disease outbreaks and natural disasters) is important for situation awareness and timely response. Social media, with increasing popularity, provide an effective way to collect event-related data from massive populations and thus a significant opportunity to dynamically monitor events as they emerge and evolve. While existing research has demonstrated the value of social media as sensors in event detection, estimating potential time spans and influenced areas of an event from social media remains challenging. Challenges include the unstable volumes of available data, the spatial heterogeneity of event activities and social media data, and the data sparsity. This paper describes a systematic approach to detecting potential spatiotemporal patterns of events by resolving these challenges through several interrelated strategies: using kernel density estimation for smoothed social media intensity surfaces; utilizing event-unrelated social media posts to help map relative event prevalence; and normalizing event indicators based on historical fluctuation. This approach generates event indicator maps and significance maps explaining spatiotemporal variations of event prevalence to identify space-time regions with potentially abnormal event activities. The approach has been applied to detect influenza activity patterns in the conterminous US using Twitter data. A set of experiments demonstrated that our approach produces high-resolution influenza activity maps that could be explained by available ground truth data.  相似文献   
252.
How to exploit various features of users and points of interest (POIs) for accurate POI recommendation is important in location-based social networks (LBSNs). In this paper, a novel POI recommendation framework, named RecNet, is proposed, which is developed based on a deep neural network (DNN) to incorporate various features in LBSNs and learn their joint influence on user behavior. More specifically, co-visiting, geographical and categorical influences in LBSNs are exploited to alleviate the data sparsity issue in POI recommendation and are converted to feature vector representations of POIs and users via feature embedding. Moreover, the embedded POIs and users are fed into a DNN pairwise to adaptively learn high-order interactions between features. Our method is evaluated on two publicly available LBSNs datasets and experimental results show that RecNet outperforms state-of-the-art algorithms for POI recommendation.  相似文献   
253.
To modernize food safety governance, we must carry out basic restructuring of its internal logic at the national level to reflect the features of contemporary Chinese society that shape food safety. This will entail establishing an overarching, macro-level conception of food safety that integrates “baseline safety”, “hub safety”, “co-constructed safety” and “endogenous safety”. These four dimensions of safety represent four fundamental requirements of food safety governance in modern Chinese society, which is a “risk society” (Beck 1992) and one that is also complex, open and pluralist. These requirements are: maximum legal liability, a unified, authoritative and efficient supervision system, a concept of social co-governance, and enterprises being the primary entities accountable for food safety. This article uses this analytical framework to interpret the basic contents of the newly revised Food Safety Law of the People’s Republic of China, and uses a focus on social co-governance to present the institutional highlights of this law and the transformation of the internal logic of food safety governance.  相似文献   
254.
Face-to-face interviews(n=860) were conducted to determine cash-gift behavior, cognition and complexity of social relations, and family water consumption for agricultural production in a typical oasis area in Northwest China. The survey results revealed cash gifts to be the second-largest expenditure(1,330 Yuan) for rural households, far beyond the average spending on health(854.1 Yuan) or education(890.8 Yuan). The amount of cash-gift expenditures indirectly reflects a family's social relations level, and our developed Social Relations Extent Coefficient—based on cash-gift and food expenditures—can directly reflect the extent or level of these relationships. Different types of farmers or farming families have different coefficients. The coefficient also shows how social station affects a family's water resource utilization, and how water is distributed among different types of farmers. Despite the current inequities, however, promotion of better agricultural techniques and large-scale cultivation in this area could help distribute water resources more equitably and effectively.  相似文献   
255.
论述了施工企业建设现代安全生产管理体系的重要性,并总结了广东煤炭地质局建设安全生产管理体系.促进安全生产的实践经验,提出了施工企业应从以建立完善安全生产责任制为核心,健全各项规章制度.加强员工的教育培训、资金投入和安全检查五个方面为重点建立现代安全生产管理体系的思路。  相似文献   
256.
A. Patel  N.J. Balmer  P. Pleasence 《Geoforum》2008,39(6):2084-2096
Despite limited research on access to advice services, it has long been assumed that access is related to geographic proximity [e.g. Blacksell, M., 1990. Social Justice and access to legal services: a geographic perspective. Geoforum 21 (4), 489–502]. The current study uses data from the English and Welsh Civil and Social Justice Survey, a large-scale nationally representative survey of respondents’ experience of and response to civil and social justice problems [Pleasence, P., 2006. Causes of Action: Civil Law and Social Justice, second ed. TSO, Norwich], to examine the impact of proximity to mainstream advice services on awareness and utilisation of services. In general, proximity of advice services had a relatively modest impact on both awareness and advice seeking. However, proximity did impact upon mode of contact and there was some evidence of difference in strategy (particularly more inaction) for isolated individuals without use of motorised transport. The suitability of different modes of advice provision for particular demographic groups are discussed, as well as implications for service delivery.  相似文献   
257.
Scholarly literature recognises the importance of social sustainability as part of the wider sustainability agenda. A wide array of concepts such as equity, social justice, democratic government, social inclusion, social capital and quality of life are thought to constitute social sustainability. Local governments are charged with delivering social programs and services to their constituency, but market logics and performance-based institutional cultures, along with limited authority and funding, constrain their capacity to respond to new initiatives. We analyse two case studies in Victoria, Australia, to explore how elements of social sustainability are articulated and operationalised within local government. Each case study involved State-level and local government partnerships in health-promotion initiatives to improve food security. Analysis was conducted on 50 primary policy documents, 22 secondary data documents and 27 interviews. Findings reveal that a systems-based or integrated approach to social sustainability was not workable but not completely ineffective. Equity was prioritised by local government in both case studies, and well acknowledged as interconnected with other social goals. Although constrained in its capacity to deliver new initiatives, local government responded to neoliberalising ideologies, as well as its constituency, by strategically focusing on a particular goal, such as equity.  相似文献   
258.
Environmental Policies Can Buttress Conservation Norms   总被引:1,自引:0,他引:1  
In an attempt to solve large-scale environmental problems, government agencies often resort to formal sanctioning systems: market-based incentives or command-and-control regulations, to promote cooperation. The purpose of this study was to investigate how the presence of these formal sanctioning systems impacts informal sanctioning systems for environmental protection. Study 1 used an experimental game to explore the influence of market-based and regulatory programs on informal sanctioning in a laboratory setting. Study 2 was a quasi-experimental field survey that compared informal sanctioning among Massachusetts residents living in towns with voluntary, mandatory, and pay-as-you-throw recycling programs. Results showed that in the presence of a formal sanctioning system, individuals felt guiltier for not engaging in the cooperative behavior and expressed more disapproval for non-cooperators. Combined, these results show that environmental policies can buttress conservation norms.  相似文献   
259.
邮轮产业已经成为国际旅游和接待业中发展速度最快、经济效益最显著的业务之一。随着全球邮轮市场的东移,中国邮轮业受到了前所未有的关注,已发展成为亚太邮轮市场的核心组成部分。随着邮轮经济的不断深化,邮轮旅游业对中国经济、社会、文化和环境的影响日渐广泛而深远,而邮轮旅游的可持续性与责任性问题将成为该产业发展的重大议题。本文对国内外文献进行整理和分析后发现,目前国内学者对邮轮旅游及其影响的审视还不够深刻,特别是对邮轮旅游业的负效应或负外部性问题没有引起足够关注,研究成果非常有限,研究视角也较为宽泛。本文主要对近15年来国外邮轮旅游可持续性与责任性方面的成果进行了综述,在对邮轮经济的有限性、邮轮旅游对自然环境破坏和社会—文化冲击等方面的成果进行梳理的基础上,提出了“负责任邮轮旅游”的系统结构与行动框架,可为中国今后邮轮旅游业持续、快速与健康发展提供理论指导与实践支持。  相似文献   
260.
基于战略性新兴产业的长江三角洲城市网络结构演变研究   总被引:12,自引:7,他引:5  
庄德林  杨羊  晋盛武  韩荣 《地理科学》2017,37(4):546-553
基于2004~2013年战略性新兴产业上市公司跨区布址数据,运用社会网络分析法对长江三角洲城市群空间结构演变规律进行了分析。研究发现:长江三角洲城市网络的主要联系流由 “Z”字形空间结构演变为“金字塔”形结构。 高行政级别城市在网络要素资源配置中占据主导地位,省会城市的中介能力呈现“倒U”型发展趋势。沪杭宁甬苏合6城市构成了长三角城市网络的核心层,核心-边缘层联系成为占据主导地位的联系方式;城市网络凝聚子群具有明显的地理粘着性,沪宁和杭州凝聚子群分别是群内联系和群际联系的标杆。  相似文献   
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