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181.
The modern age has heralded a shift from the industrial society, in which natural resources are crucial input factors for the economy, towards a knowledge society. To date, sustainability literature has treated knowledge—and in particular digital artifacts—mainly as a means to the end of achieving sustainable development. In this conceptual paper, we argue that digital artifacts themselves ought also to be considered as resources, which also need to be sustainable. While over-consumption is a problem facing natural resources, with sustainable digital artifacts, underproduction, and underuse are the biggest challenges. In our view, the sustainability of digital artifacts improves their potential impact on sustainable development. A theoretical foundation for digital artifacts and their ecosystem allows us to present the relevant research on digital information, knowledge management, digital goods, and innovation literature. Based on these insights, we propose ten basic conditions for sustainable digital artifacts and their ecosystem to ensure that they provide the greatest possible benefit for sustainable development. We then apply those characteristics to four exemplary cases: Linux kernel development, Bitcoin cryptocurrency, the Wikipedia project, and the Linking Open Drug Data repositories. The paper concludes with a research agenda identifying topics for sustainability scholars and information systems academics, as well as practitioners. A number of suggestions for future studies on digital sustainability are also put forward.  相似文献   
182.
The quality of education in Kenya’s public elementary schools has continued to drop, which is an ironic outcome in the wake of the introduction of tuition-exempt primary education. This removal of tuition costs led to a surge in primary education enrollment that overwhelmed the existing educational infrastructure. Overcapacity in classrooms led to frustrated teachers and mediocre delivery of content amid the overstretched resources and limited education budget. To remedy this situation, the government has begun introducing various information and communication technologies (ICTs) in schools to supplement current resources. This comes with mixed results. This paper aims to demonstrate effective strategies for integrating low-cost ICT-based materials in schools in developing countries through a community of practice. Three schools were used to illustrate integration of sustainable ICT-based education in a style of classroom characteristic in developing schools. Development and use of prerecorded DVD-based content was proposed as an effective solution. A comparative study was undertaken to evaluate the differences in student comprehension and educator delivery of education involving a digital, ICT-integrated classroom and a traditional, analog-type teaching method classroom to underscore the empirical evidence of the effectiveness of introducing a low-cost ICT-based program. This study also shows that teachers are better positioned to lead the design and development of appropriate and innovative materials. Furthermore, to cope with the immense amount of materials that need developing to correspond with the curriculum, it shows that with the emergence of a community of practice of teachers, many suitable low-cost materials can be developed. This takes place through an iterative collaboration as opposed to traditional top-down approaches, which have a proven record of failure.  相似文献   
183.
Sustainability science is a solution-oriented discipline. Yet, there are few theory-rich discussions about how this orientation structures the efforts of sustainability science. We argue that Niklas Luhmann’s social system theory, which explains how societies communicate problems, conceptualize solutions, and identify pathways towards implementation of solutions, is valuable in explaining the general structure of sustainability science. From Luhmann, we focus on two key concepts. First, his notion of resonance offers us a way to account for how sustainability science has attended and responded to environmental risks. As a product of resonance, we reveal solution-oriented research as the strategic coordination of capacities, resources, and information. Second, Luhmann’s interests in self-organizing processes explain how sustainability science can simultaneously advance multiple innovations. The value logic that supports this multiplicity of self-organizing activities as a recognition that human and natural systems are complex coupled and mutually influencing. To give form to this theoretical framework, we offer case evidence of renewable energy policy formation in Texas. Although the state’s wealth is rooted in a fossil-fuel heritage, Texas generates more electricity from wind than any US state. It is politically antagonistic towards climate-change policy, yet the state’s reception of wind energy technology illustrates how social and environmental systems can be strategically aligned to generate solutions that address diverse needs simultaneously. This case demonstrates that isolating climate change—as politicians do as a separate and discrete problem—is incapable of achieving sustainable solutions, and resonance offers researchers a framework for conceptualizing, designing, and communicating meaningfully integrated actions.  相似文献   
184.
185.
原位化学氧化(in situ chemical oxidation,ISCO)是一种高效便捷的去除地下水有机污染物的技术,相比于多孔介质,岩溶地下河中ISCO技术应用还未见报道.为了更好地认识ISCO技术在岩溶地下河石油污染修复中应用的可行性,使用过硫酸盐(persulfate,PS)作为化学氧化剂,在实验室利用碳酸盐...  相似文献   
186.
Environmental Science and Pollution Research - Municipal solid waste (MSW) incineration power generation is an important treatment technology, which has been widely concerned in recent years. It is...  相似文献   
187.
Environmental Science and Pollution Research - In this work, the Ni-doped anatase TiO2 single crystals loaded on activated carbon (Ni-T/AC) were synthesized by a sol–gel method. The chemical...  相似文献   
188.
人工神经网络和专家系统在污水生物处理系统中的应用   总被引:1,自引:0,他引:1  
对近年来国内外污水生物处理系统中人工神经网络和专家系统的应用进行了简要的回顾。分析了废水生物处理工艺难于控制的原因及人工神经网络和专家系统的结构和特点。结果表明.国外智能控制发展迅速,并且应用领域遍及污水生物处理的各个方面,国内尚处于起步阶段。简要探讨了废水生物处理智能控制今后应深入研究的问题及方向。  相似文献   
189.
由于化肥的过度使用 ,造成地下水中硝酸盐的污染日益严重。饮用水中高浓度的硝酸盐对人类健康会产生极大的威胁。本文综述了催化还原脱除水中硝酸根的研究进展和现状 ,并对其发展趋势进行了简单的论述。  相似文献   
190.
短程硝化的实现、维持与过程控制的研究现状   总被引:4,自引:0,他引:4  
短程生物脱氮技术目前倍受人们的关注,国内外学者对短程硝化提出了多种实现及维持的控制途径,但仍存在着一些问题。由于活性污泥法中DO,ORP,pH的变化规律从不同角度不同程度地反映了生物脱氮反应的进程,所以用它们作为控制参数就可以对生物脱氮反应进行过程控制。在分析中,通过对国内外短程硝化控制途径的研究现状与发展趋势的分析和总结,针对目前在实现短程硝化及维持短程硝化各种途径中存在的问题,提出了通过在线检测DO,pH,ORP来实现与维持短程硝化的新思路。  相似文献   
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