997 resultados para dead core model
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Construction of hydroelectric dams in tropical regions has been contributing significantly to forest fragmentation. Alterations at edges of forest fragments impact plant communities that suffer increases in tree damage and dead, and decreases in seedling recruitment. This study aimed to test the core-area model in a fragmented landscape caused by construction of a hydroelectric power plant in the Brazilian Amazon. We studied variations in forest structure between the margin and interiors of 17 islands of 8-100 hectares in the Tucuruí dam reservoir, in two plots (30 and >100m from the margin) per island. Mean tree density, basal area, seedling density and forest cover did not significantly differ between marginal and interior island plots. Also, no significant differences were found in liana density, dead tree or damage for margin and interior plots. The peculiar topographic conditions associated with the matrix habitat and shapes of the island seem to extend edge effects to the islands' centers independently of the island size, giving the interior similar physical microclimatic conditions as at the edges. We propose a protocol for assessing the ecological impacts of edge effects in fragments of natural habitat surrounded by induced (artificial) edges. The protocol involves three steps: (1) identification of focal taxa of particular conservation or management interest, (2) measurement of an "edge function" that describes the response of these taxa to induced edges, and (3) use of a "Core-Area Model" to extrapolate edge function parameters to existing or novel situations.
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3rd Workshop on High-performance and Real-time Embedded Systems (HIRES 2015). 21, Jan, 2015. Amsterdam, Netherlands.
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Suomalainen metsäteollisuus on muutoksen partaalla. Uutisissa on nähty miten metsäyrityksen sulkevat tehtaita ja paperikoneita. Suomalaisessa metsäteollisuudessa keskitytään tällä hetkellä lähinnä kulujen alentamiseen ja tuottavuuden parantamiseen. Edellytyssille, että suomalainen metsäteollisuus pysyy kilpailukykyisenä, ovat kuitenkinuudet innovaatiot ja toimialojen välinen yhteistyö. Työn tavoitteena oli luoda toimintamalli UPM-Kymmene Oyj:lle, minkä avulla ydinliiketoimintaan kuulumattomat tuote- ja palveluideat saataisiin hyödynnettyä. Aihe on erittäin ajankohtainen, mikäli halutaan pitää tuotanto jatkossakin Suomessa. Luotumalli painottaa pk-sektorin roolia ja potentiaalia kehittää UPM-Kymmeneltä peräisin olevia ja heidän ydinliiketointaan kuulumattomista tuote ja palveluideoistauusia yrityksiä, tuotteita ja palveluita. Malli edustaa uudenlaista ajattelutapaa ja sen käyttöönotto vaatii perinteisen yrityskulttuurin uudistamista UPM-Kymmenessä.
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The aim of the study was to create an easily upgradable product costing model for laser welded hollow core steel panels to help in pricing decisions. The theory section includes a literature review to identify traditional and modern cost accounting methodologies, which are used by manufacturing companies. The theory section also presents the basics of steel panel structures and their manufacturing methods and manufacturing costs based on previous research. Activity-Based costing turned out to be the most appropriate methodology for the costing model because of wide product variations. Activity analysis and the determination of cost drivers based on observations and interviews were the key steps in the creation of the model. The created model was used to test how panel parameters affect the costs caused by the main manufacturing stages and materials. By comparing cost structures, it was possible to find the panel types that are the most economic and uneconomic to manufacture. A sensitivity analysis proved that the model gives sufficiently reliable cost information to support pricing decisions. More reliable cost information could be achieved by determining the cost drivers more accurately. Alternative methods for manufacturing the cores were compared with the model. The comparison proved that roll forming can be more advantageous and flexible than press brake bending. However, more extensive research showed that roll forming is possible only when the cores are designed to be manufactured by roll forming. Due to that fact, when new panels are designed consideration should be given to the possibility of using roll forming.
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We determine the properties of the core-periphery model with three regions and compare our results with those of the standard 2-region model. The conditions for the stability of dispersion and concentration are established. As in the 2-region model, dispersion and concentration can be simultaneously stable. We show that the 3-region (2-region) model favours the concentration (dispersion) of economic activity. Furthermore, we provide some results for the n-region model. We show that the stability of concentration of the 2-region model implies that of any model with an even number of regions.
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The Open Provenance Model is a model of provenance that is designed to meet the following requirements: (1) To allow provenance information to be exchanged between systems, by means of a compatibility layer based on a shared provenance model. (2) To allow developers to build and share tools that operate on such a provenance model. (3) To define provenance in a precise, technology-agnostic manner. (4) To support a digital representation of provenance for any 'thing', whether produced by computer systems or not. (5) To allow multiple levels of description to coexist. (6) To define a core set of rules that identify the valid inferences that can be made on provenance representation. This document contains the specification of the Open Provenance Model (v1.1) resulting from a community-effort to achieve inter-operability in the Provenance Challenge series.
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Model predictive control (MPC) applications in the process industry usually deal with process systems that show time delays (dead times) between the system inputs and outputs. Also, in many industrial applications of MPC, integrating outputs resulting from liquid level control or recycle streams need to be considered as controlled outputs. Conventional MPC packages can be applied to time-delay systems but stability of the closed loop system will depend on the tuning parameters of the controller and cannot be guaranteed even in the nominal case. In this work, a state space model based on the analytical step response model is extended to the case of integrating time systems with time delays. This model is applied to the development of two versions of a nominally stable MPC, which is designed to the practical scenario in which one has targets for some of the inputs and/or outputs that may be unreachable and zone control (or interval tracking) for the remaining outputs. The controller is tested through simulation of a multivariable industrial reactor system. (C) 2012 Elsevier Ltd. All rights reserved.