966 resultados para Abstraction Hierarchy
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Purpose – This paper aims to evaluate critically the conventional binary hierarchical representation of the formal/informal economy dualism which reads informal employment as a residual and marginal sphere that has largely negative consequences for economic development and needs to be deterred. Design/methodology/approach – To contest this depiction, the results of 600 household interviews conducted in Ukraine during 2005/2006 on the extent and nature of their informal employment are reported. Findings – Informal employment is revealed to be an extensively used form of work and, through a richer and more textured understanding of the multiple roles that different forms of informal employment play, a form of work that positively contributes to economic and social development, acting both as an important seedbed for enterprise creation and development and as a primary vehicle through which community self-help is delivered in contemporary Ukraine. Research limitations/implications – This survey reveals that depicting informal employment as a hindrance to development and deterring engagement in this sphere results in state authorities destroying the entrepreneurial endeavour and active citizenship that other public policies are seeking to nurture. The paper concludes by addressing how this public policy paradox might start to be resolved. Originality/value – This paper is one of the first to document the role of informal employment in nurturing enterprise creation and development as well as community exchange.
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This study of concentrating solar thermal power generation sets out to evaluate the main existing collection technologies using the framework of the Analytical Hierarchy Process (AHP). It encompasses parabolic troughs, heliostat fields, linear Fresnel reflectors, parabolic dishes, compound parabolic concentrators and linear Fresnel lenses. These technologies are compared based on technical, economic and environmental criteria. Within these three categories, numerous sub-criteria are identified; similarly sub-alternatives are considered for each technology. A literature review, thermodynamic calculations and an expert workshop have been used to arrive at quantitative and qualitative assessments. The methodology is applied principally to a case study in Gujarat in north-west India, though case studies based on the Sahara Desert, Southern Spain and California are included for comparison. A sensitivity analysis is carried out for Gujarat. The study concludes that the linear Fresnel lens with a secondary compound parabolic collector, or the parabolic dish reflector, is the preferred technology for north-west India.
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This article discusses property rights, corporate governance frameworks and privatisation outcomes in the Central–Eastern Europe and Central Asia (CEECA) region. We argue that while CEECA still suffers from deficient ‘higher order’ institutions, this is not attracting sufficient attention from international institutions like EBRD and the World Bank, which focus on ‘lower order’ indicators. We discuss factors that may alleviate the negative impact of the weakness in institutional environment and argue for the pecking order of privatisation, where equivalent privatisation is given a priority but speed is not compromised.
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The main purpose of this research is to develop and deploy an analytical framework for measuring the environmental performance of manufacturing supply chains. This work's theoretical bases combine and reconcile three major areas: supply chain management, environmental management and performance measurement. Researchers have suggested many empirical criteria for green supply chain (GSC) performance measurement and proposed both qualitative and quantitative frameworks. However, these are mainly operational in nature and specific to the focal company. This research develops an innovative GSC performance measurement framework by integrating supply chain processes (supplier relationship management, internal supply chain management and customer relationship management) with organisational decision levels (both strategic and operational). Environmental planning, environmental auditing, management commitment, environmental performance, economic performance and operational performance are the key level constructs. The proposed framework is then applied to three selected manufacturing organisations in the UK. Their GSC performance is measured and benchmarked by using the analytic hierarchy process (AHP), a multiple-attribute decision-making technique. The AHP-based framework offers an effective way to measure and benchmark organisations’ GSC performance. This study has both theoretical and practical implications. Theoretically it contributes holistic constructs for designing a GSC and managing it for sustainability; and practically it helps industry practitioners to measure and improve the environmental performance of their supply chain. © 2013 Copyright Taylor and Francis Group, LLC. CORRIGENDUM DOI 10.1080/09537287.2012.751186 In the article ‘Green supply chain performance measurement using the analytic hierarchy process: a comparative analysis of manufacturing organisations’ by Prasanta Kumar Dey and Walid Cheffi, Production Planning & Control, 10.1080/09537287.2012.666859, a third author is added which was not included in the paper as it originally appeared. The third author is Breno Nunes.
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Term dependence is a natural consequence of language use. Its successful representation has been a long standing goal for Information Retrieval research. We present a methodology for the construction of a concept hierarchy that takes into account the three basic dimensions of term dependence. We also introduce a document evaluation function that allows the use of the concept hierarchy as a user profile for Information Filtering. Initial experimental results indicate that this is a promising approach for incorporating term dependence in the way documents are filtered.
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The main purpose of the study is to develop an integrated framework for managing project risks by analyzing risk across project, work package and activity levels, and developing responses. Design/methodology/approach: The study first reviews the literature of various contemporary risk management frameworks in order to identify gaps in project risk management knowledge. Then it develops a conceptual risk management framework using combined analytic hierarchy process (AHP) and risk map for managing project risks. The proposed framework has then been applied to a 1500 km oil pipeline construction project in India in order to demonstrate its effectiveness. The concerned project stakeholders were involved through focus group discussions for applying the proposed risk management framework in the project under study. Findings: The combined AHP and risk map approach is very effective to manage project risks across project, work package and activity levels. The risk factors in project level are caused because of external forces such as business environment (e.g. customers, competitors, technological development, politics, socioeconomic environment). The risk factors in work package and activity levels are operational in nature and created due to internal causes such as lack of material and labor productivity, implementation issues, team ineffectiveness, etc. Practical implications: The suggested model can be applied to any complex project and helps manage risk throughout the project life cycle. Originality/value: Both business and operational risks constitute project risks. In one hand, the conventional project risk management frameworks emphasize on managing business risks and often ignore operational risks. On the other hand, the studies that deal with operational risk often do not link them with business risks. However, they need to be addressed in an integrated way as there are a few risks that affect only the specific level. Hence, this study bridges the gaps. © 2010 Elsevier B.V. All rights reserved.
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The existing method of pipeline health monitoring, which requires an entire pipeline to be inspected periodically, is both time-wasting and expensive. A risk-based model that reduces the amount of time spent on inspection has been presented. This model not only reduces the cost of maintaining petroleum pipelines, but also suggests an efficient design and operation philosophy, construction methodology, and logical insurance plans. The risk-based model uses the analytic hierarchy process (AHP), a multiple-attribute decision-making technique, to identify the factors that influence failure on specific segments and to analyze their effects by determining probability of risk factors. The severity of failure is determined through consequence analysis. From this, the effect of a failure caused by each risk factor can be established in terms of cost, and the cumulative effect of failure is determined through probability analysis. The technique does not totally eliminate subjectivity, but it is an improvement over the existing inspection method.
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We have investigated how optimal coding for neural systems changes with the time available for decoding. Optimization was in terms of maximizing information transmission. We have estimated the parameters for Poisson neurons that optimize Shannon transinformation with the assumption of rate coding. We observed a hierarchy of phase transitions from binary coding, for small decoding times, toward discrete (M-ary) coding with two, three and more quantization levels for larger decoding times. We postulate that the presence of subpopulations with specific neural characteristics could be a signiture of an optimal population coding scheme and we use the mammalian auditory system as an example.
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The issues relating fuzzy sets definition are under consideration including the analogue for separation axiom, statistical interpretation and membership function representation by the conditional Probabilities.
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When modeling game situations of incomplete information one usually considers the players’ hierarchies of beliefs, a source of all sorts of complications. Harsányi (1967-68)’s idea henceforth referred to as the ”Harsányi program” is that hierarchies of beliefs can be replaced by ”types”. The types constitute the ”type space”. In the purely measurable framework Heifetz and Samet (1998) formalize the concept of type spaces and prove the existence and the uniqueness of a universal type space. Meier (2001) shows that the purely measurable universal type space is complete, i.e., it is a consistent object. With the aim of adding the finishing touch to these results, we will prove in this paper that in the purely measurable framework every hierarchy of beliefs can be represented by a unique element of the complete universal type space.
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Sono dette “challenged networks” quelle reti in cui lunghi ritardi, frequenti partizionamenti e interruzioni, elevati tassi di errore e di perdita non consentono l’impiego dei classici protocolli di comunicazione di Internet, in particolare il TCP/IP. Il Delay-/Disruption-Tolerant Networking (DTN) è una soluzione per il trasferimento di dati attraverso queste reti. L’architettura DTN prevede l’introduzione, sopra il livello di trasporto, del cosiddetto “bundle layer”, che si occupa di veicolare messaggi, o bundle, secondo l’approccio store-and-forward: ogni nodo DTN conserva persistentemente un bundle finché non si presenta l’opportunità di inoltrarlo al nodo successivo verso la destinazione. Il protocollo impiegato nel bundle layer è il Bundle Protocol, le cui principali implementazioni sono tre: DTN2, l’implementazione di riferimento; ION, sviluppata da NASA-JPL e più orientata alle comunicazioni spaziali; IBR-DTN, rivolta soprattutto a dispositivi embedded. Ciascuna di esse offre API che consentono la scrittura di applicazioni in grado di inviare e ricevere bundle. DTNperf è uno strumento progettato per la valutazione delle prestazioni in ambito DTN. La più recente iterazione, DTNperf_3, è compatibile sia con DTN2 che con ION nella stessa versione del programma, grazie all’introduzione di un “Abstraction Layer” che fornisce un’unica interfaccia per l’interazione con le diverse implementazioni del Bundle Protocol e che solo internamente si occupa di invocare le API specifiche dell’implementazione attiva. Obiettivo della tesi è estendere l’Abstraction Layer affinché supporti anche IBR-DTN, cosicché DTNperf_3 possa essere impiegato indifferentemente su DTN2, ION e IBR DTN. Il lavoro sarà ripartito su tre fasi: nella prima esploreremo IBR DTN e le sue API; nella seconda procederemo all’effettiva estensione dell’Abstraction Layer; nella terza verificheremo il funzionamento di DTNperf a seguito delle modifiche, sia in ambiente esclusivamente IBR-DTN, sia ibrido.