298 research outputs found

    Model Pola Laju Aliran Fluida dengan Luas Penampang yang Berbeda Menggunakan Metode Beda Hingga

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    The writer has done a research on the model of rate pattern of liquid fluid flow by using flow model that has different pattern. The Equation of continuity was used to solve flow rate case, while Equation of Laplace two dimensions was used for numerical case by finite difference methods by using MATLAB R2009b (version 7.9.0.529). The purpose of fluid research was making flow pattern then analyzing fluid flow to each point in dimensions on Equation of Laplace. The methodology used in this research was evaluating Equation of Laplace concept, identifying the problems, two dimensions of Laplace equation used, completing the numerics by using finite difference methods, and completing analitics for simple cases. The results showed that there was no significant between analytical and computation of fluid flow rate. It can be seen the average of error value is close to zero and the highest error value is 0,000,778 % . Even in various geometry problems, the flow pattern can is be also visualized

    Model evaluation and ensemble modelling of surface-level ozone in Europe and North America in the context of AQMEII

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    More than ten state-of-the-art regional air quality models have been applied as part of the Air Quality Model Evaluation International Initiative (AQMEII). These models were run by twenty independent groups in Europe and North America. Standardised modelling outputs over a full year (2006) from each group have been shared on the web-distributed ENSEMBLE system, which allows for statistical and ensemble analyses to be performed by each group. The estimated ground-level ozone mixing ratios from the models are collectively examined in an ensemble fashion and evaluated against a large set of observations from both continents. The scale of the exercise is unprecedented and offers a unique opportunity to investigate methodologies for generating skilful ensembles of regional air quality models outputs. Despite the remarkable progress of ensemble air quality modelling over the past decade, there are still outstanding questions regarding this technique. Among them, what is the best and most beneficial way to build an ensemble of members? And how should the optimum size of the ensemble be determined in order to capture data variability as well as keeping the error low? These questions are addressed here by looking at optimal ensemble size and quality of the members. The analysis carried out is based on systematic minimization of the model error and is important for performing diagnostic/probabilistic model evaluation. It is shown that the most commonly used multi-model approach, namely the average over all available members, can be outperformed by subsets of members optimally selected in terms of bias, error, and correlation. More importantly, this result does not strictly depend on the skill of the individual members, but may require the inclusion of low-ranking skill-score members. A clustering methodology is applied to discern among members and to build a skilful ensemble based on model association and data clustering, which makes no use of priori knowledge of model skill. Results show that, while the methodology needs further refinement, by optimally selecting the cluster distance and association criteria, this approach can be useful for model applications beyond those strictly related to model evaluation, such as air quality forecasting. (C) 2012 Elsevier Ltd. All rights reserved.Peer reviewe

    Distinct positions underpin ecosystem services for poverty alleviation

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    AbstractAs the concept of ecosystem services is applied more widely in conservation, its users will encounter the issue of poverty alleviation. Policy initiatives involving ecosystem services are often marked by their use of win-win narratives that conceal the trade-offs they must entail. Modelling this paper on an earlier essay about conservation and poverty, we explore the different views that underlie apparent agreement. We identify five positions that reflect different mixes of concern for ecosystem condition, poverty and economic growth, and we suggest that acknowledging these helps to uncover the subjacent goals of policy interventions and the trade-offs they involve in practice. Recognizing their existence and foundations can ultimately support the emergence of more legitimate and robust policies.</jats:p

    Research priorities for managing the impacts and dependencies of business upon food, energy, water and the environment

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    Delivering access to sufficient food, energy and water resources to ensure human wellbeing is a major concern for governments worldwide. However, it is crucial to account for the ‘nexus’ of interactions between these natural resources and the consequent implications for human wellbeing. The private sector has a critical role in driving positive change towards more sustainable nexus management and could reap considerable benefits from collaboration with researchers to devise solutions to some of the foremost sustainability challenges of today. Yet opportunities are missed because the private sector is rarely involved in the formulation of deliverable research priorities. We convened senior research scientists and influential business leaders to collaboratively identify the top forty questions that, if answered, would best help companies understand and manage their food-energy-water-environment nexus dependencies and impacts. Codification of the top order nexus themes highlighted research priorities around development of pragmatic yet credible tools that allow businesses to incorporate nexus interactions into their decision-making; demonstration of the business case for more sustainable nexus management; identification of the most effective levers for behaviour change; and understanding incentives or circumstances that allow individuals and businesses to take a leadership stance. Greater investment in the complex but productive relations between the private sector and research community will create deeper and more meaningful collaboration and cooperation.This work was supportedby the Economic and Social Research Council [Grant Number ES/L01632X/1] and is part of the Nexus Network Initiative. WJS is funded by Arcadia

    Natural capital informing decisions: from promise to practice

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    This is the accepted manuscript of a paper that will be published in PNAS. It is currently under an infinite embargo.The central challenge of the 21st century is to develop economic, social, and governance systems capable of ending poverty and achieving sustainable levels of population and consumption while securing the life-support systems underpinning current and future human well-being. Essential to meeting this challenge is the incorporation of natural capital and the ecosystem services it provides into decision-making. Here, we explore progress and crucial gaps at this frontier, reflecting upon the 10 years since the Millennium Ecosystem Assessment. We focus on three key dimensions of progress and ongoing challenges: raising awareness of the interdependence of ecosystems and human well-being; advancing the fundamental, interdisciplinary science of ecosystem services; and implementing this science in decisions to restore natural capital and use it sustainably. Awareness of human dependence on nature is at an all-time high, the science of ecosystem services is rapidly advancing, and talk of natural capital is now common from governments to corporate boardrooms. However, successful implementation is still in early stages. We explore why ecosystem service information has yet to fundamentally change decision-making and suggest a path forward that emphasizes: 1) developing solid evidence linking decisions to impacts on natural capital and ecosystem services, and then to human well-being, 2) working closely with leaders in government, business, and civil society to develop the knowledge, tools, and practices necessary to integrate natural capital and ecosystem services into everyday decision-making; and 3) reforming institutions to change policy and practices to better align private short-term goals with societal long-term goals.http://dx.doi.org/10.1073/pnas.150375111

    Poorer without It? The Neglected Role of the Natural Environment in Poverty and Wellbeing

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    The relationship between sustainable development’s prime goal, human wellbeing, and the natural environment has been narrowly conceived. This paper focuses on the possibility and the implications of treating the natural environment as a ‘constituent’, or internal element, of the concepts of wellbeing and poverty, as opposed to a ‘determinant’, or instrumental, external factor. Our review of philosophical accounts and conceptual frameworks of wellbeing and poverty suggests that treating the environment as a constituent element is philosophically sound, conceptually robust and empirically grounded. We argue that failing to consider these missing environmental aspects can result in an incomplete capturing of the multiple dimensions of wellbeing and poverty, and their underlying drivers. This broader framing of the environment– wellbeing relationship has the potential to inform a new generation of individual level wellbeing and poverty indicators, creating measures of multidimensional poverty that reflect the broadened scope ambitiously articulated in the Sustainable Development Goals

    Теорія та практика менеджменту безпеки

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    У збірнику подано тези доповідей та виступів учасників Міжнародної науково-практичної конференції, присвяченої питанням теорії менеджменту безпеки, безпеки особистості, прикладним аспектам забезпечення соціальної, екологічної, економічної безпеки підприємств, питанням механізму забезпечення соціоекологоекономічної безпеки регіону, проблемам забезпечення національної безпеки
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