939 resultados para Multi-source case studies


Relevância:

100.00% 100.00%

Publicador:

Relevância:

100.00% 100.00%

Publicador:

Resumo:

This paper proposes a hierarchical energy management system for multi-source multi-product (MSMP) microgrids. Traditional energy hub based scheduling method is combined with a hierarchical control structure to incorporate transient characteristics of natural gas flow and dynamics of energy converters in microgrids. The hierarchical EMS includes a supervisory control layer, an optimizing control layer, and an execution control layer. In order to efficiently accommodate the systems multi time-scale characteristics, the optimizing control layer is decomposed into three sub-layers: slow, medium and fast. Thermal, gas and electrical management systems are integrated into the slow, medium, and fast control layer, respectively. Compared with wind energy, solar energy is easier to integrate and more suitable for the microgrid environment, therefore, potential impacts of the hierarchical EMS on MSMP microgrids is investigated based on a building energy system integrating photovoltaic and microturbines. Numerical studies indicate that by using a hierarchical EMS, MSMP microgrids can be economically operated. Also, interactions among thermal, gas, and electrical system can be effectively managed.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Municipalities that engage in recreation planning have the potential to use their resources more effectively. However, successful planning means getting the plan off the shelf and implemented. This study investigated the factors that influenced municipal recreation plan implementation in three municipalities. Interviews were conducted with eleven key informants (recreation directors, planning consultants, a city councillor, and members of plan steering committees). The findings of this study suggested that because the implementation of recreation plans occurs in a highly political environment, recreation professionals will need effective strategies to get their plans implemented and that implementation can be facilitated by developing or expanding strategies that: (l) build the power of the recreation department within the municipal government structure; (2) build support for recreation within the local community; and (3) build the political and organizational capacity in the recreation department.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

In the second half of the twentieth century we saw the environmental debate escalate into one of the most challenging and complex issues that authorities at international, national, regional and municipal levels have to deal with. The inherent complexity of environmental problems, which brings out the interconnections between the economic, socio-cultural and ecological dimensions of the territory, is increased by the social, scientific and political focuses of the debate, and their interdependencies. In the framework of governance, scientific and technical assessments are a relevant but not “unique” source for legitimating environmental policymaking. The discussion is opened towards the consideration of different existing perspectives on the environment. The main objective of the present study is to systematize and explore in-depth the perspectives brought by feminism and gender to environmental governance. What is the specificity of a feminist and gender outlook? In what sense does it bring new light to environmental governance processes? Such questions are explored empirically and theoretically.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Tendering is one of the stages in construction procurement that requires extensive information and documents exchange. However, tender documents are not always clear in practice. The aim of this study was to ascertain the clarity and adequacy of tender documents used in practice. Access was negotiated into two UK construction firms and the whole tender process for two projects was shadowed for 6-7 weeks in each firm using an ethnographic approach. A significant amount of tender queries, amendments and addenda were recorded. This showed that quality of tender documentation is still a problem in construction despite the existence of standards like Co-ordinated Project Information (1987) and British Standard 1192 (1984 and 1990) that are meant to help in producing clear and consistent project information. Poor quality tender documents are a source of inaccurate estimates, claims and disputes on contracts. Six recommendations are presented to help in improving the quality of tender documentation. Further research is needed into the recommendations to help improve the quality of tender documents, perhaps in conjunction with an industry-wide investigation into the level of incorporation of CPI principles in practice.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

A significant number of children with learning disabilities may hold negative attributions about themselves which not only impact on their willingness to learn but put themselves at risk of developing depression. A multi-disciplinary assessment team found evidence for the existence of at least two distinct patterns of learning disability. It was concluded that interventions must focus not only on content areas but on the individual attributions the child holds about his or her ability and potential.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Eight case studies of academics at a new multi-campus, multi-state Catholic university form the basis of the research. A particular focus is examining how the academics struggle to construct their work identity against the global higher education background of changing government policies, reduced funding and major shifts in thinking about the functions of universities; and also the background of within-university changes: its new research-orientation, its particular form of corporate managerialist administration.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Post-colonial states in the Asian region have frequently been subject to political tensions derived from their multi-ethnic make-up and, what some have argued to be, the failure of states to adequately represent the interests of their ethnic minorities. This article will look at examples of where states in Asia have failed to adequately represent or otherwise incorporate their ethnic minorities as full and equal citizens. It also considers the range of responses to such perceived or actual state failure in adequately incorporating all citizens, including inter-ethnic and racial violence and separatist conflict. The article will conclude by considering conceptual and actual models of state organization intended to resolve racial and ethnic tensions in the Asian region.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

In the past, the focus of drainage design was on sizing pipes and storages in order to provide sufficient network capacity. This traditional approach, together with computer software and technical guidance, had been successful for many years. However, due to rapid population growth and urbanisation, the requirements of a “good” drainage design have also changed significantly. In addition to water management, other aspects such as environmental impacts, amenity values and carbon footprint have to be considered during the design process. Going forward, we need to address the key sustainability issues carefully and practically. The key challenge of moving from simple objectives (e.g. capacity and costs) to complicated objectives (e.g. capacity, flood risk, environment, amenity etc) is the difficulty to strike a balance between various objectives and to justify potential benefits and compromises. In order to assist decision makers, we developed a new decision support system for drainage design. The system consists of two main components – a multi-criteria evaluation framework for drainage systems and a multi-objective optimisation tool. The evaluation framework is used for the quantification of performance, life-cycle costs and benefits of different drainage systems. The optimisation tool can search for feasible combinations of design parameters such as the sizes, order and type of drainage components that maximise multiple benefits. In this paper, we will discuss real-world application of the decision support system. A number of case studies have been developed based on recent drainage projects in China. We will use the case studies to illustrate how the evaluation framework highlights and compares the pros and cons of various design options. We will also discuss how the design parameters can be optimised based on the preferences of decision makers. The work described here is the output of an EngD project funded by EPSRC and XP Solutions.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The main goals of this Ph.D. study are to investigate the regional and global geophysical components related to present polar ice melting and to provide independent cross validation checks of GIA models using both geophysical data detected by satellite mission, and geological observations from far field sites, in order to determine a lower and upper bound of uncertainty of GIA effect. The subject of this Thesis is the sea level change from decades to millennia scale. Within ice2sea collaboration, we developed a Fortran numerical code to analyze the local short-term sea level change and vertical deformation resulting from the loss of ice mass. This method is used to investigate polar regions: Greenland and Antarctica. We have used mass balance based on ICESat data for Greenland ice sheet and a plausible mass balance for Antarctic ice sheet. We have determined the regional and global fingerprint of sea level variations, vertical deformations of the solid surface of the Earth and variations of shape of the geoid for each ice source mentioned above. The coastal areas are affected by the long wavelength component of GIA process. Hence understanding the response of the Earth to loading is crucial in various contexts. Based on the hypothesis that Earth mantle materials obey to a linear rheology, and that the physical parameters of this rheology can be only characterized by their depth dependence, we investigate the Glacial Isostatic Effect upon the far field sites of Mediterranean area using an improved SELEN program. We presented new and revised observations for archaeological fish tanks located along the Tyrrhenian and Adriatic coast of Italy and new RSL for the SE Tunisia. Spatial and temporal variations of the Holocene sea levels studied in central Italy and Tunisia, provided important constraints on the melting history of the major ice sheets.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Soil degradation is widespread in the Ethiopian Highlands. Its negative impacts on soil productivity contribute to the extreme poverty of the rural population. Soil conservation is propagated as a means of reducing soil erosion, however, it is a costly investment for small-scale farming households. The present study is an attempt to show whether or not selected mechanical Soil and Water Conservation (SWC) technologies are profitable from a farmer’s point of view. A financial Cost-Benefit Analysis (CBA) is carried out to assess whether or not the considered SWC technologies are profitable from a farmer’s point of view. The CBA is supplemented by an evaluation of aspects from the economic and institutional environment. Whether or not soil conservation is profitable from a farmer’s point of view depends on a broad range of factors from the ecological, economic, political, institutional and socio-cultural sphere and also depends on the technology and the prevailing farming system. Because these factors are closely interlinked, it is often not sufficient to change or influence one to make SWC profitable. Several recommendations are formulated with regard to improving the profitability of SWC investments from a farmer’s point of view. Because the reasons for unsustainable resource use are manifold and highly interlinked, only a multi-stakeholder, multi-level and multi-objective approach is likely to offer solutions that address the underlying problems adequately.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The estimation of power losses due to wind turbine wakes is crucial to understanding overall wind farm economics. This is especially true for large offshore wind farms, as it represents the primary source of losses in available power, given the regular arrangement of rotors, their generally largerdiameter and the lower ambient turbulence level, all of which conspire to dramatically affect wake expansion and, consequently, the power deficit. Simulation of wake effects in offshore wind farms (in reasonable computational time) is currently feasible using CFD tools. An elliptic CFD model basedon the actuator disk method and various RANS turbulence closure schemes is tested and validated using power ratios extracted from Horns Rev and Nysted wind farms, collected as part of the EU-funded UPWIND project. The primary focus of the present work is on turbulence modeling, as turbulent mixing is the main mechanism for flow recovery inside wind farms. A higher-order approach, based on the anisotropic RSM model, is tested to better take into account the imbalance in the length scales inside and outside of the wake, not well reproduced by current two-equation closure schemes.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Purpose: To investigate the effect of cueing on communicative responses of children with multiple disabilities in an educational setting. It was hypothesized that differences would exist in teacher interactional styles and the use of orienting cues would increase the communicative responses of the participants. Method: A naturalistic observation research method was employed in order to examine the interaction of three student-teacher dyads in three special schools. Three different activity types were videotaped from which interactions were coded and analysed. Results: Multi-modal cueing facilitated communicative responses of children with Rett syndrome. However, increased communication opportunities provided by caregivers did not elicit increased responses from the girls. Conclusion: There is a difference in cueing by teachers in their interactions with children with multiple disabilities. Also, more frequent communicative interactions did not necessarily lead to increased student responses. It is suggested that amount and type of cueing may need to be considered to be effective in generating student responses. The small number of participants, however, means findings should be viewed cautiously and that more research is indicated.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

With the globalisation of world business, the border-crossing activities between organisations have substantially increased. Organisations not only need to handle supply functions, but also play a tremendous role in demand simulation through integration both inside the firm and outside with business partners and customers. Logistics has become more and more mature and sophisticated by taking on an external focus, incorporating suppliers and customers in the business processes, with all the supply chain functions integrated into a whole. By minimising the costs in the value chain or providing customised services, logistics acts as a major source of competitive advantages and profitability. To meet this goal, it would require the integration of activities to focus on customer-oriented measures. Customer service and logistics activities are a chain of interdependent activities that supplement each other to facilitate the flow of information, goods and cash within the value chain. The absence of one activity may imply some specific channels need to supplement another unit. Generally, this paper is to study the impact of corporate strategy, technology and customer satisfaction on the firm’s performance, filling the gap of good customer service effects on long-term profits. Two international delivery providers, UPS and FedEx, are studied to realise the critical success factors of express logistics.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

This is a multiple case study of the leadership language of three senior women working in a large corporation in Bahrain. The study’s main aim is to explore the linguistic practices the women leaders use with their colleagues and subordinates in corporate meetings. Adopting a Foucauldian (1972) notion of ‘discourses’ as social practices and a view of gender as socially constructed and discursively performed (Butler 1990), this research aims to unveil the competing discourses which may shape the leadership language of senior women in their communities of practice. The research is situated within the broader field of Sociolinguistics and the specific field of Language and Gender. To address the research aim, a case study approach incorporating multiple methods of qualitative data collection (observation, interviews, and shadowing) was utilised to gather information about the three women leaders and produce a rich description of their use of language in and out of meeting contexts. For analysis, principles of Qualitative Data Analysis (QDA) were used to organise and sort the large amount of data. Also, Feminist Post- Structuralist Discourse Analysis (FPDA) was adopted to produce a multi-faceted analysis of the subjects, their language leadership, power relations, and competing discourses in the context. It was found that the three senior women enact leadership differently making variable use of a repertoire of conventionally masculine and feminine linguistic practices. However, they all appear to have limited language resources and even more limiting subject positions; and they all have to exercise considerable linguistic expertise to police and modify their language in order to avoid the ‘double bind’. Yet, the extent of this limitation and constraints depends on the community of practice with its prevailing discourses, which appear to have their roots in Islamic and cultural practices as well as some Western influences acquired throughout the company’s history. It is concluded that it may be particularly challenging for Middle Eastern women to achieve any degree of equality with men in the workplace because discourses of Gender difference lie at the core of Islamic teaching and ideology.