The production of biogas through anaerobic digestion is one of the technological solutions to convert biomass into a readily usable fuel. Biogas can replace natural gas, if the biogas is upgraded to green gas. To contribute to the EU-target to reduce Green House Gases emissions, the installed biogas production capacity and the amount of farm-based biomass, as a feedstock, has to be increased. A model was developed to describe a green gas production chain that consists of several digesters connected by a biogas grid to anupgrading and injection facility. The model calculates costs and energy use for 1 m3 of green gas. The number of digesters in the chain can be varied to find results for different configurations. Results are presented for a chain with decentralized production of biogas, i.e. a configuration with several digesters, and a centralized green gas production chain using a single digester. The model showed that no energy advantage per produced m3 green gas can be created using a biogas grid and decentralized digesters instead of one large-scale digester. Production costs using a centralized digester are lower, in the range of5 Vct to 13 Vct per m3, than in a configuration of decentralized digesters. The model calculations also showed the financial benefit for an operator of a small-scale digester wishing to produce green gas in the cooperation with nearby other producers. E.g. subsidies and legislation based on environmental arguments could encourage the use of decentralized digesters in a biogas grid.
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Sustainable consumption is interlinked with sustainable production. This chapter will introduce the closed-loop production, the circular economy, the steady state economy, and Cradle to Cradle (C2C) models of production. It will reflect on the key blockages to a meaningful sustainable production and how these could be overcome, particularly in the context of business education. The case study of the course for bachelor’s students within International Business Management Studies (IBMS) program at three Universities of Applied Science (vocational schools), and at Leiden University College in The Netherlands will be discussed. Student teams from these schools were given the assignment to make a business plan for a selected sponsor company in order to advise them how to make a transition from a linear to circular economy model. These case studies will illustrate the opportunities as well as potential pitfalls of the closed loop production models. The results of case studies’ analysis show that there was a mismatch between expectations of the sponsor companies and those of students on the one hand and a mismatch between theory and practice on the other hand. The former mismatch is explained by the fact that the sponsor companies have experienced a number of practical constraints when confronted with the need for the radical overhaul of established practices within the entire supply chain and students have rarely considered the financial viability of the "ideal scenarios" of linear-circular transitions. The latter mismatch applies to what students had learned about macro-economic theory and the application through micro-economic scenarios in small companies. https://www.springer.com/gp/book/9783319656076 LinkedIn: https://www.linkedin.com/in/helenkopnina/
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Peer-to-peer (P2P) energy trading has been recognized as an important technology to increase the local self-consumption of photovoltaics in the local energy system. Different auction mechanisms and bidding strategies haven been investigated in previous studies. However, there has been no comparatively analysis on how different market structures influence the local energy system’s overall performance. This paper presents and compares two market structures, namely a centralized market and a decentralized market. Two pricing mechanisms in the centralized market and two bidding strategies in the decentralized market are developed. The results show that the centralized market leads to higher overall system self-consumption and profits. In the decentralized market, some electricity is directly sold to the grid due to unmatchable bids and asks. Bidding strategies based on the learning algorithm can achieve better performance compared to the random method.
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Many quality aspects of software systems are addressed in the existing literature on software architecture patterns. But the aspect of system administration seems to be a bit overlooked, even though it is an important aspect too. In this work we present three software architecture patterns that, when applied by software architects, support the work of system administrators: PROVIDE AN ADMINISTRATION API, SINGLE FILE LOCATION, and CENTRALIZED SYSTEM LOGGING. PROVIDE AN ADMINISTRATION API should solve problems encountered when trying to automate administration tasks. The SINGLE FILE LOCATION pattern should help system administrators to find the files of an application in one (hierarchical) place. CENTRALIZED SYSTEM LOGGING is useful to prevent coming up with several logging formats and locations. Abstract provided by the authors. Published in PLoP '13: Proceedings of the 20th Conference on Pattern Languages of Programs ACM.
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On the internet we enjoy a continuously growing generation of web applications enabling anyone to create and publish online content in a simple way, to link content and to share it with others. The internet has become a social software platform sailing under the Web 2.0 flag, creating revolutionary changes along the way: the individual, the end-user, comes first and can benefit optimally from an environment which has the following keywords: radically user-oriented, de-centralized, collective and massive. An environment in which each participant not only listens, but can also make his own voice heard: the Social Web.
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According to the critics of conventional sustainability models, particularly within the business context, it is questionable whether the objective of balancing the social, economic and environmental triad is feasible, and whether human equality and prosperity (as well as population growth) can be achieved with the present rate of natural degradation (Rees 2009). The current scale of human economic activity on Earth is already excessive; finding itself in a state of unsustainable ‘overshoot’ where consumption and dissipation of energy and material resources exceed the regenerative and assimilative capacity of supportive ecosystems (Rees 2012). Conceptualizing the current ‘politics of unsustainability’, reflected in mainstream sustainability debates, Blühdorn (2011) explores the paradox of wanting to ‘sustain the unsustainable, noting that the socio-cultural norms underpinning unsustainability support denial of the gravity of our planetary crises. This denial concerns anything from the imminence of mass extinctions to climate change. As Foster (2014) has phrased it: ‘There was a brief window of opportunity when the sustainability agenda might, at least in principle, have averted it’. That agenda, however, has failed. Not might fail, nor even is likely to fail – but has already failed. Yet, instead of acknowledging this failure and moving on from the realization of the catastrophe to the required radical measures, the optimists of sustainable development and ecological modernization continue to celebrate the purported ‘balance' between people, profit and planet. This is an Accepted Manuscript of a book chapter published by Routledge/CRC Press in "A Future Beyond Growth: Towards a Steady State Economy" on 4/14/16 ,available online: https://doi.org/10.4324/9781315667515 LinkedIn: https://www.linkedin.com/in/helenkopnina/
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This chapter will introduce the circular economy (CE) and Cradle to Cradle (C2C) models of sustainable production. It will reflect on the key blockages to a meaningful sustainable production and how these could be overcome, particularly in the context of business education. The case study of the course for bachelor’s students within International Business Management Studies (IBMS), and at University College in The Netherlands will be discussed. These case studies will illustrate the opportunities as well as potential pitfalls of the closed loop production models. The results of case studies’ analysis show that there was a mismatch between expectations of the sponsor companies and those of students on the one hand and a mismatch between theory and practice on the other hand. Helpful directions for future research and teaching practice are outlined. https://www.springer.com/gp/book/9783319713113#aboutBook https://www.linkedin.com/in/helenkopnina/
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This paper describes an agent-based software infrastructure for agile industrial production. This production is done on special devices called equiplets. A grid of these equiplets connected by a fast network is capable of producing a variety of different products in parallel. The multi-agent-based underlying systems uses two kinds of agents: an agent representing the product and an agent representing the equiplet.
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Closed loop or ‘circular’ production systems known as Circular Economy and Cradle to Cradle represent a unique opportunity to radically revise the currently wasteful system of production. One of the challenges of such systems is that circular products need to be both produced locally with minimum environmental footprint and simultaneously satisfy demand of global consumers. This article presents a literature review that describes the application of circular methodologies to education for sustainability, which has been slow to adopt circular systems to the curriculum. This article discusses how Bachelor and Master-level students apply their understanding of these frameworks to corporate case studies. Two assignment-related case studies are summarized, both of which analyze products that claim to be 'circular'. The students' research shows that the first case, which describes the impact of a hybrid material soda bottle, does not meet circularity criteria. The second case study, which describes products and applications of a mushroom-based material, is more sustainable. However, the students' research shows that the manufacturers have omitted transport from the environmental impact assessment and therefore the mushroom materials may not be as sustainable as the manufacturers claim. As these particular examples showed students how green advertising can be misleading, applying “ideal” circularity principles as part of experiential learning could strengthen the curriculum. Additionally, this article recommends that sustainable business curriculum should also focus on de-growth and steady-state economy, with these radical alternatives to production becoming a central focus of education of responsible citizens. https://doi.org/10.1016/j.jclepro.2019.02.005 LinkedIn: https://www.linkedin.com/in/helenkopnina/
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We tested the hypothesis that in human ageing a decreased intramuscular acylcarnitine status is associated with (pre-)frailty, reduced physical performance and altered mitochondrial function. Results showed that intramuscular total carnitine levels and acetylcarnitine levels were lower in (pre-)frail old females compared to fit old females and young females, whereas no differences were observed in males. The low intramuscular acetylcarnitine levels in females correlated with low physical performance, even after correction for muscle mass (%), and were accompanied with lowered expression of genes involved in mitochondrial energy production and functionality. We concluded that in (pre-)frail old females, intramuscular total carnitine levels and acetylcarnitine levels are decreased, and this decrease is associated with reduced physical performance and low expression of a wide range of genes critical for mitochondrial function. The results stress the importance of taking sex differences into account in ageing research.
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