3,966 research outputs found
A weighted sustainability index for selection of optimal operating plans
The Wimmera Mallee Pipeline Project (WMPP) provides reticulated water to 36 towns and about 6000 farms across an area of approximately 2 million hectares and forms part of the Wimmera-Mallee Water Supply System (WMWSS). The WMWSS is a multi-reservoir system located in Western Victoria (Australia) which is operated to meet a range of conflicting interests for water using complex operating rules. Since completion in 2010, the pipeline has vastly improved efficiencies in the supply of water, with water savings being returned to the environment, existing consumptive use and new development. However, one of the major challenges for managers of these water recovery projects is to determine the most effective or optimal operational strategy to meet the needs of all water users. In Victoria, these often conflicting interests to water have traditionally been addressed through a consultative process supported by surface water simulation modelling. Simulation models attempt to represent all the major characteristics of a system and are suited to examine “what if?” scenarios. Whilst such models are highly effective in demonstrating the effect of changes in system operation, the modelling process is limited to finding one solution at a time for a given set of conditions. Optimisation models have also proven to be effective tools but unlike simulation models are characterised by a numeric search technique and are better suited to address “what should be?” questions. In recent times there has been growing interest in linking optimisation techniques with simulation models in order to build on the strengths of both modelling approaches in the search for optimal solutions. The general structure of this combined modelling technique provides for an iterative process; simulation outputs are used to quantify the effect of candidate solutions which are in turn passed to the search engine to find optimal solutions. The process of selecting the most preferred optimal solution brings together two aspects of multi-objective optimisation, namely; (i) the quantitative characteristics of these solutions relative to other solutions; and (ii) the higher level qualitative information in the form of stakeholders’ preferences. The aim of this study is to incorporate stakeholder preferences into a sustainability index which has been previously used to evaluate and compare optimal operating plans for the WMWSS. In that previous study, Godoy et al. (2015) applied a multi-objective optimisation and sustainability assessment approach to an 18-objective function multi-objective optimisation problem (MOOP) which represented a range of interests for water. For the present study, the same interests are described in terms of three broad categories i.e. strong environmental preferences, strong social preferences, and strong preferences for the needs of consumptive users. A weighted sustainability index is presented which incorporates these preferences in the original sustainability index formulation. This weighted sustainability index is used to select preferred optimal operating plans previously found by the optimisation-simulation modelling. The results showed that the weighted sustainability index provided a simple means to incorporate stakeholders’ preferences into the selection process and inform the decision maker of a stakeholder’s uncertainty about their values and priorities for water. © 2017 Proceedings - 22nd International Congress on Modelling and Simulation, MODSIM 2017. All rights reserved
Sub-Riemannian geodesics on nested principal bundles
We study the interplay between geodesics on two non-holono\-mic systems that
are related by the action of a Lie group on them. After some geometric
preliminaries, we use the Hamiltonian formalism to write the parametric form of
geodesics. We present several geometric examples, including a non-holonomic
structure on the Gromoll-Meyer exotic sphere and twistor space.Comment: 10 page
Effect of a Voltage Probe on the Phase-Coherent Conductance of a Ballistic Chaotic Cavity
The effect of an invasive voltage probe on the phase-coherent conduction
through a ballistic chaotic cavity is investigated by random-matrix theory. The
entire distribution P(G) of the conductance G is computed for the case that the
cavity is coupled to source and drain by two point contacts with a quantized
conductance of 2 e^2/h, both in the presence (beta = 1) and absence (beta = 2)
of time-reversal symmetry. The loss of phase-coherence induced by the voltage
probe causes a crossover from P(G) ~ G^(-1 + beta/2) to a Gaussian centered at
G = e^2/h with a beta-dependent width. ***Submitted to Physical Review B.***Comment: 9 pages, REVTeX-3.0, 4 postscript figures appended as self-extracting
archive, INLO-PUB-941020
Aplicações ricas no controle de doenças da soja.
Este artigo apresenta a utilização de recursos de aplicações ricas para internet no controle de doenças da soja, explorando novas formas de publicar e acessar informações, por meio de componentes que estendem a capacidade das aplicações web e proporcionam ambientes interativos e colaborativos. As aplicações foram baseadas no conceito de web 2.0, amplamente utilizado e de comprovada relevância para o uso da internet como plataforma de aplicações em diversas áreas. O uso desses recursos se deu no desenvolvimento de uma aplicação web para o controle e monitoramento da ferrugem asiática da soja no Brasil. O resultado obtido demonstrou que essas tecnologias proporcionam aplicações web diferenciadas, tanto para entrada como para saída de informações, apresentando grande contribuição no desenvolvimento de soluções informatizadas para o controle de doenças da cultura da soja, podendo ser aplicadas também para outras culturas. RICH INTERNET APPLICATIONS IN SOYBEAN DISEASE CONTROL. This paper presents the use of Rich Internet Applications resources to help on soybean diseases control and explores a new ways to publish and access information, through components that extend the capabilities of web applications and provide interactive and collaborative environments. The applications were based on web 2.0 concepts, widely used and proven relevance. The use of these resources was made by developing a web application for the control and monitoring of Asian soybean rust in Brazil. The results showed that these technologies provide differenced web applications, both for input and for output information, presenting a great contribution to the development of computerized solutions for the control of soybean diseases, which can also be applied to other cultures.SBIAGRO
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