99 resultados para BIM Implementation
Resumo:
This paper describes the implementation, using a microprocessor, of a self-tuning control algorithm on a heating system. The algorithm is based on recursive least squares parameter estimation with a state-space, pole placement design criterion and shows how the controller behaves when applied to an actual system.
Resumo:
Over the last few years, load growth, increases in intermittent generation, declining technology costs and increasing recognition of the importance of customer behaviour in energy markets have brought about a change in the focus of Demand Response (DR) in Europe. The long standing programmes involving large industries, through interruptible tariffs and time of day pricing, have been increasingly complemented by programmes aimed at commercial and residential customer groups. Developments in DR vary substantially across Europe reflecting national conditions and triggered by different sets of policies, programmes and implementation schemes. This paper examines experiences within European countries as well as at European Union (EU) level, with the aim of understanding which factors have facilitated or impeded advances in DR. It describes initiatives, studies and policies of various European countries, with in-depth case studies of the UK, Italy and Spain. It is concluded that while business programmes, technical and economic potentials vary across Europe, there are common reasons as to why coordinated DR policies have been slow to emerge. This is because of the limited knowledge on DR energy saving capacities; high cost estimates for DR technologies and infrastructures; and policies focused on creating the conditions for liberalising the EU energy markets.
Resumo:
Purpose – The purpose of this research was twofold. First, to investigate the views of occupiers in a typical UK city on the importance of various sustainability issues, their perceived impact of different sustainability drivers and willingness to pay. Second, the environmental and social performance of existing buildings in that city was examined. Design/methodology/approach – The research focuses on buildings of 10,000 feet2 or more that have been constructed in the Bristol city-region in the UK over the past 50 years. The buildings in the sample are located in the city centre and in out-of-town business parks. A questionnaire survey investigated the views of occupiers and follow-up interviews looked more closely at the sustainability performance of the existing stock. Findings – The findings indicate that, as far as occupiers are concerned, the strongest drivers are consumer demand and staff demand. Green features of a building appear to rank low in the overall building selection preference structure and a willingness to pay a premium for green features was indicated. The interviews uncovered barriers to progress as well as initiatives to reduce both energy consumption and the environmental impact of office space. Practical implications – The paper identifies progress and issues which could form obstacles to improving the environmental performance of office buildings. It is argued that there is a need to focus on energy efficiency. Originality/value – This paper explores the linkage between the perception and use of office space by occupants and how this affects the environmental performance of this space.
Resumo:
In the first part of this article, we introduced a new urban surface scheme, the Met Office – Reading Urban Surface Exchange Scheme (MORUSES), into the Met Office Unified Model (MetUM) and compared its impact on the surface fluxes with respect to the current urban scheme. In this second part, we aim to analyze further the reasons behind the differences. This analysis is conducted by a comparison of the performance of the two schemes against observations and against a third model, the Single Column Reading Urban model (SCRUM). The key differences between the three models lie in how each model incorporates the heat stored in the urban fabric and how the surface-energy balance is coupled to the underlying substrate. The comparison of the models with observations from Mexico City reveals that the performance of MORUSES is improved if roof insulation is included by minimizing the roof thickness. A comparison of MORUSES and SCRUM reveals that, once insulation is included within MORUSES, these two models perform equally well against the observations overall, but that there are differences in the details of the simulations at the roof and canyon level. These differences are attributed to the different representations of the heat-storage term, specifically differences in the dominant frequencies captured by the urban canopy and substrate, between the models. These results strongly suggest a need for an urban model intercomparison exercise. Copyright © 2010 Royal Meteorological Society and Crown Copyright
Resumo:
This paper describes the formulation of a new urban scheme, MORUSES (Met Office–Reading Urban Surface Exchange Scheme) for use in the Met Office Unified Model. The implementation of the new scheme ensures that (1) the new scheme offers more flexibility in the parametrization of the building properties, and hence provides a more realistic representation of the fluxes; (2) the bulk outputs are in satisfactory agreement with previous observational studies; and (3) the impact of the new scheme on the energy balance fluxes is similar to the impact of the current urban scheme when set up to mimic it. As well as having a better physical basis, MORUSES also gains in flexibility in applications and adaptations to different urban materials as well as urban planning. The new scheme represents the urban area as a composition of two tiles, a canyon and a roof, using a simple 2D geometry. Sensitivity analysis to canyon geometry and thickness of the roof canopy emphasizes the gain in flexibility captured by the new scheme. Copyright © 2010 Royal Meteorological Society and Crown Copyright
Resumo:
This paper presents an overview of the European Union involvement in agricultural restructuring. By way of introduction it looks at the processes of farm replication operating in Europe and the forces behind them. It then considers the wider application of EU measures in each Member State and how they interrelate with the national property laws and social customs. In conclusion the paper appraises the restructuring policies by examining the balance between legitimising the concentration of property rights amongst a minority and the fragmentation of estates between the majority.
Resumo:
This paper evaluates the implementation of environmental policy in the County of Hertfordshire during the 1980's and early 1990's. It emphasises that the recent growth of interest in environmental policy and sustainable planning initiatives should not cause researchers and practitioners to ignore the long history and experience of environmental policy implementation in local government. By looking at the experience of strategic environmental policy in Hertfordshire, the paper identifies the successes and failures of a range of implementation tools utilised by the County and district planning authorities to progress policies concerned with the conservation and improvement of urban and rural environments. It concludes that the planning authorities of Hertfordshire have stabilised the deterioration in the County's environment and have established some programmes which provide good examples of coordinated action in environmental policy implementation. These types of mechanism will need to be built upon in the new policy epoch where environmental sustainability and capacity planning take centre stage.
Resumo:
Both the (5,3) counter and (2,2,3) counter multiplication techniques are investigated for the efficiency of their operation speed and the viability of the architectures when implemented in a fast bipolar ECL technology. The implementation of the counters in series-gated ECL and threshold logic are contrasted for speed, noise immunity and complexity, and are critically compared with the fastest practical design of a full-adder. A novel circuit technique to overcome the problems of needing high fan-in input weights in threshold circuits through the use of negative weighted inputs is presented. The authors conclude that a (2,2,3) counter based array multiplier implemented in series-gated ECL should enable a significant increase in speed over conventional full adder based array multipliers.
Resumo:
Armed with the ‘equity’ and ‘conservation’ arguments that have a deep resonance with farming communities, developing countries are crafting a range of measures designed to protect farmers’ access to innovations, reward their contributions to the conservation and enhancement of plant genetic resources and provide incentives for sustained on-farm conservation. These measures range from the commericialization of farmers’ varieties to the conferment of a set of legally enforceable rights on farming communities – the exercise of which is expected to provide economic rewards to those responsible for on-farm conservation and innovation. The rights-based approach has been the cornerstone of legislative provision for implementing farmers’ rights in most developing countries. In drawing up these measures, developing countries do not appear to have systematically examined or provided for the substantial institutional capacity required for the effective implementation of farmers’ rights provisions. The lack of institutional capacity threatens to undermine any prospect of serious implementation of these provisions. More importantly, the expectation that significant incentives for on-farm conservation and innovation will flow from these ‘rights’ may be based on a flawed understanding of the economics of intellectual property rights. While farmers’ rights may provide only limited rewards for conservation, they may still have the effect of diluting the incentives for innovative institutional breeding programs – with the private sector increasingly relying on non-IPR instruments to profit from innovation. The focus on a rights-based approach may also draw attention away from alternative stewardship-based approaches to the realization of farmers’ rights objectives.