207 research outputs found
Kinematic Self-Similar Solutions of Locally Rotationally Symmetric Spacetimes
This paper contains locally rotationally symmetric kinematic self-similar
perfect fluid and dust solutions. We consider three families of metrics which
admit kinematic self-similar vectors of the first, second, zeroth and infinite
kinds, not only for the tilted fluid case but also for the parallel and
orthogonal cases. It is found that the orthogonal case gives contradiction both
in perfect fluid and dust cases for all the three metrics while the tilted case
reduces to the parallel case in both perfect fluid and dust cases for the
second metric. The remaining cases give self-similar solutions of different
kinds. We obtain a total of seventeen independent solutions out of which two
are vacuum. The third metric yields contradiction in all the cases.Comment: 17 pages, accepted for publication Brazilian J. Physic
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Knowledge representation within information systems in manufacturing environments
This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University.Representing knowledge as information content alone is insufficient in providing us with an understanding of the world around us. A combination of context as well as reasoning of the information content is fundamental to representing knowledge in an information system. Knowledge Representation is typically concerned with providing structures and theories that are used as a basis for intelligent reasoning. For this research however, the author defines an alternative meaning, which is related to how knowledge is used in a given context. Thus, this dissertation provides a contribution to the field of knowledge within information systems, in terms of the development of a frame-of-reference that will support the reader in navigating through the different forms of explicit and tacit knowledge use within the manufacturing industry. In doing so, the dissertation also presents the generation of a novel classification of three forms of knowledge (Structural, Interpretive and Evaluative forms); the development of a conceptual framework which highlights the drivers for knowledge transformation; and the development of a conceptual model which seeks to envelop both the content as well as the context of knowledge (Semiotic as well as Symbiotic factors). This is established through the use of an Empirical, Quantitative case study approach, that seeks to explore an interpretivist view of knowledge representation within two information systems contexts, within two UK manufacturing organisations. The first case study presents how a-priori knowledge assumptions are used in a computer aided engineering decision-making task within a high technology manufacturing company. The second case study shows how knowledge is used within the IT/IS investment evaluation decision making process, within a manufacturing SME. In doing so, both case studies attempt to elucidate the inherent, underlying relationship between explicit and tacit knowledge, via a frame-of-reference developed by the author which defines key drivers for knowledge transformation
Neural and Evolutionary Computing in Finite Element Analysis
This paper presents a discussion of current neural and evolutionary techniques, applied to the field of Finite Element Analysis and Finite Element Mesh Generation. This numerical method is widely used in many science, and engineering analyses to compute many forms of static and dynamic fields and potentials, such as heat, stress or velocity, on a mesh of interconnecting elements. The accuracy of the underlying finite element mesh determines the magnitude of the error of the solution to the differential equations. Meshes have to be adapted to limit this as far as possible, usually in an a-posteriori sense. These techniques have been widely automated and used with great success, but no means yet exist which allow the efficient a-priori evaluation of a prospective finite element mesh before the equations are to be solved. As such, the application of expert and heuristic knowledge is largely required to produce visible benefits from adaptive remeshing processes. This paper discusses how neural and evolutionary architectures have addressed this problem and presents a complementary evolutionary model, which may aid in the generation of finite element meshes, as a result of on-going research into the development of such \u27intelligent\u27 techniques
Information technology and performance management for build-to-order supply chains
En las siguientes líneas se plantea un artículo de reflexión que tiene en cuenta parte del marco teórico que sustenta la investigación titulada “Prácticas pedagógicas que promueven la competencia argumentativa escrita (CAE) en niños campesinos de los grados
4° y 5° del Centro Educativo Municipal La Caldera, Sede Principal de Pasto”, desarrollada en el año 2012. En él se contemplan los aportes de las ciencias del lenguaje y la comunicación, la teoría de la argumentación, la didáctica de la lengua escrita y los géneros discursivos, que dan cuenta de la necesidad de desarrollar la
capacidad crítica en los estudiantes a través de la argumentación, lo cual implica transformar las prácticas pedagógicas para que se alejen de la transmisión de conocimientos y den paso a la comunicación, para que la palabra escrita sea apropiada de manera significativa
Sustainable food security futures: Perspectives on food waste and information across the food supply chain
YesThe purpose of this paper is to signpost the genesis of food security and associated factors such that organisations, enterprises, policy makers and interested stakeholders can seek to explore and understand this important societal issue. The challenges that food security poses are eclectic in nature and cut through country, society, organisation and individual boundaries. Only through identifying these factors – hence identifying underlying factors of food waste and usage of information within food supply chains to untangle them – can we adopt enterprise interventions in order to initiate and mitigate food security risk.
As a viewpoint piece, there is no empirical work to report in this paper. An exploratory review of the literature has allowed for the extraction of food security concerns that need the attention of stakeholders across the enterprise to ensure robust food supply chains can be are created, maintained and sustained through a better understanding and usage of information, knowledge and data
This paper articulates six constructs that underpin the challenges of establishing food security. It is suggested that information relating to factors may support decision-makers within communities, organisations and enterprises to better understand these factors that then contribute towards enhanced food security. Relevant strategies or policies can then emerge and be developed such that strategic as well as operational interventions can be prioritised across national, regional or industry level. Underpinning the above, the waste within and across the food supply chain contributes to the six factors, also highlighting where additional focus may need to be applied to sustain food supply chains.
This paper is a position paper that does not offer factual insight but rather highlights a direction of thought that others can consider exploring as part of wider research agendas in the topical area where enterprise, organisational, and information-based contributions may support the development of strategy-led food security policy.
This paper provides reassuring insights that will help decision and policy makers assemble their thoughts when it comes to prioritising their communications and interventions amongst organisational/enterprise-level stakeholder groups involved in food security and food supply chain contexts.
This paper has highlighted the need for more research around the human and organisational factors that are identified as both underpinning the need for food security and, as drivers of waste throughout the food supply chain. Indeed, there is further work needed to highlight the inter-relationships that exist and, which then feed into resulting interventions.
To raise the importance of food security amongst differing stakeholder community groups at the organisational and enterprise level
User Adoption of a CRM-based Information System Within a Financial Services Organization: An Empirical Analysis
Financial Services firms require processes and systems which can support and maintain customer-related information for the purposes of core business-focussed activity. Specifically within the investment banking sector, the importance and criticality of such customer information underpins the firm’s ability to transact sales, trading and other advisory-based services in an efficient and relevant manner. The design and development of Customer Relationship Management (CRM) systems to address the given external vs. internal customer information touchpoints, therefore provides a vital link between financial services professionals, client data and business processes. In doing so, the input of CRM user requirements is a key step in deriving benefit from such a technology solution. This paper henceforth identifies and details user requirements and experiences of such an information system within a case study company and highlights pertinent issues for the adoption of such systems within the given sector
Knowledge representation within information systems in manufacturing environments
Representing knowledge as information content alone is insufficient in providing us with an understanding of the world around us. A combination of context as well as reasoning of the information content is fundamental to representing knowledge in an information system. Knowledge Representation is typically concerned with providing structures and theories that are used as a basis for intelligent reasoning. For this research however, the author defines an alternative meaning, which is related to how knowledge is used in a given context. Thus, this dissertation provides a contribution to the field of knowledge within information systems, in terms of the development of a frame-of-reference that will support the reader in navigating through the different forms of explicit and tacit knowledge use within the manufacturing industry. In doing so, the dissertation also presents the generation of a novel classification of three forms of knowledge (Structural, Interpretive and Evaluative forms); the development of a conceptual framework which highlights the drivers for knowledge transformation; and the development of a conceptual model which seeks to envelop both the content as well as the context of knowledge (Semiotic as well as Symbiotic factors). This is established through the use of an Empirical, Quantitative case study approach, that seeks to explore an interpretivist view of knowledge representation within two information systems contexts, within two UK manufacturing organisations. The first case study presents how a-priori knowledge assumptions are used in a computer aided engineering decision-making task within a high technology manufacturing company. The second case study shows how knowledge is used within the IT/IS investment evaluation decision making process, within a manufacturing SME. In doing so, both case studies attempt to elucidate the inherent, underlying relationship between explicit and tacit knowledge, via a frame-of-reference developed by the author which defines key drivers for knowledge transformation.EThOS - Electronic Theses Online ServiceGBUnited Kingdo
Food security across the enterprise: a puzzle, problem or mess for a circular economy?
YesPurpose – The purpose of this paper is to explore the use, applicability and relevance of strategic planning as a process and tool when applied to exploring food security challenges, in the context of existing research on food security and food waste in the food supply chain. The issues associated with robust and resilient food supply chains within a circular economy are increasingly being seen as supportive of creating enhanced levels of food security but the authors argue that this is only sustainable when strategically planned as part of
a cross-enterprise, information-rich and complex supply chain. The relevance of the Political, Economic,
Social, Technological, Legal and Environmental (PESTLE) strategic planning tool is explored to establish
whether it can play a role tacking the complexity of food insecurity (i.e. a lack of food security).
Design/methodology/approach – This is a viewpoint piece therefore as a result, thought, normative
literature and supposition are used as a means to ground and orientate the views of the authors.
Findings – The authors identify and conclude that strategic planning tools like PESTLE across enterprises
may not be relevant in supporting the reduction of food insecurity. This conclusion is predicated on the
heightened level of complexity surrounding the pursuit of food security and the simplistic categorisation of PESTLE factors in a linear fashion that underpin this tool. Rather, the authors’ call for the use of strategic planning tools that are able to capture a large number of inter-related factors holistically.
Practical implications – This insight to the inter-related factors that contribute to food insecurity will
allow policy developers, decision makers and others to develop their understanding of how strategic planning can support increased levels of food security within a circular economy and across cross-enterprises.
Originality/value – The authors contribute to the literature through a new insight of how normative
strategic planning tools need to evolve in a complex, inter-connected world of international business and geo-politics. In doing so, it is expected that this research will motivate others to develop their line of enquiry around uncovering and exploring those inter-relationships connecting PESTLE factors
Classification of Spherically Symmetric Static Spacetimes according to their Matter Collineations
The spherically symmetric static spacetimes are classified according to their
matter collineations. These are studied when the energy-momentum tensor is
degenerate and also when it is non-degenerate. We have found a case where the
energy-momentum tensor is degenerate but the group of matter collineations is
finite. For the non-degenerate case, we obtain either {\it four}, {\it five},
{\it six} or {\it ten} independent matter collineations in which four are
isometries and the rest are proper. We conclude that the matter collineations
coincide with the Ricci collineations but the constraint equations are
different which on solving can provide physically interesting cosmological
solutions.Comment: 15 pages, no figure, Late
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