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Showing 51 to 59 of 59 (0.015 seconds)| 51 |
Technological innovation to support the decision-making process for open pit mining: the application of technological models and semi-mobile in-pit crushing and conveying scenario\'s evaluation. / Inovações tecnológicas para suportar o processo decisório em lavra a céu aberto: a aplicação de modelos tecnológicos e de análise de britagem semimóvel em cava com transportador de correias.Nunes, Rodrigo Augusto 01 April 2019 (has links)
This work presents two innovative ways to evaluate mining projects. The first is the application of a Technological Model in a copper-gold mine and the second is a decision making model to evaluate the benefit of semi-mobile in pit crusher and conveyor alternatives during the early stages of mining projects. In order to improve the process and to maximize the production and/or value of a mining project, there needs to be an integration of the geology, the mine plan, the processing and the geometallurgy data. In order to accomplish this, a new methodology is proposed for the creation of a technological model. This model can be interpreted as the consolidation of the different models required for a better understanding of the geological and technical information of the deposit. This concept was developed and applied at a copper and gold mine site located in Brazil. Based on the evaluation of different blasting and mill productivity scenarios through a pit-to-plant approach, it was possible to obtain operational short-term gains such as a 10.7% increase in the plant production rate and a 2.2% increase in the crusher\'s feed rate with little or no capital investment. Another important issue faced by mining companies is related to material handling. A significant cost in the operating budget of most mining operations arises from purchasing and maintaining haulage trucks. Recently, in-pit crushing and conveying (IPCC) has been subject to research because of its potential to reduce haulage costs. A decision-making model was created to identify early on in a project whether or not the semi-mobile IPCC (SMIPCC) is an appropriate alternative to the conventional truck haulage based on the loading and hauling approaches. The method is based on cost analysis and the evaluation of environmental impacts, being successfully tested at an existing open-pit mine, where the results indicated that the IPCC was the most cost-effective option for the operation. Although the IPCC\'s initial CAPEX was 60% higher than the conventional approach, the IPCC\'s OPEX was 43% lower, resulting in a 28% reduction of the life-of-mine net present cost (NPC). / Este trabalho apresenta duas maneiras inovadoras de avaliar projetos de mineração. A primeira é a elaboração e aplicação do modelo tecnológico para uma mina de cobre e ouro já a segunda refere-se à confecção de um modelo de tomada de decisão a ser usado para a análise dos benefícios de aplicação de britagem semimóvel em cava. Para melhorar os processos e maximizar a produção e/ou o valor de um projeto de mineração, existe a necessidade de integração dos dados de geologia, planejamento de mina, beneficiamento e geometalurgia. Com esse foco, uma nova metodologia foi proposta para a criação do modelo tecnológico. Este modelo pode ser interpretado como a consolidação dos diferentes modelos necessários para uma melhor compreensão das informações geológicas e técnicas do depósito. Este conceito foi desenvolvido e aplicado em uma mina de cobre de ouro localizada no Brasil. Com base na avaliação de diferentes cenários de perfuração e desmonte de rochas e de produtividade do moinho, usando uma abordagem de mina-usina, foi possível obter ganhos operacionais de curto prazo, tais como um aumento de 10,7% na taxa de produção de usina e um aumento de 2,2% na taxa de alimentação da britagem com pouco ou nenhum investimento de capital. Uma outra questão relevante para empresas de mineração é o transporte de material. Um custo significativo na maioria das minas surge da compra e manutenção de caminhões de transporte. A britagem em cava e correias (IPCC em inglês) vem sido avaliada em diversos casos devido ao seu potencial para reduzir os custos de transporte. Neste estudo, um modelo de tomada de decisão foi criado para identificar em etapas iniciais de um projeto os benefícios de aplicação de IPCC semimóvel (SMIPCC em inglês) em comparação com método convencional, exclusivamente por caminhões. O método baseia-se na análise de custos e na avaliação de impactos ambientais testado em uma mina a céu aberto, onde os resultados indicaram que o SMIPCC foi a opção mais econômica para a operação. Embora o investimento inicial do IPCC foi 60% maior do que a abordagem convencional, o custo operacional do IPCC foi 43% menor, resultando em uma redução de 28% do custo total a valor presente.
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On the uncertainties and dynamics of Pacific interannual and decadal climate variability and climate changeFurtado, Jason C. 11 November 2010 (has links)
Tropical and extratropical Pacific decadal climate variability substantially impact physical and biological systems in the Pacific Ocean and strongly influence global climate through teleconnection patterns. Current understanding of Pacific decadal climate variability centers around the El Niño-Southern Oscillation (ENSO), the Aleutian Low (AL), and the Pacific Decadal Oscillation (PDO). However, recent literature has highlighted the emerging roles of secondary modes of variability of the tropical and extratropical Pacific atmosphere and ocean in global climate change: the Central Pacific Warming (CPW) phenomenon, the North Pacific Oscillation (NPO), and the North Pacific Gyre Oscillation (NPGO). This work analyzes the statistics and uncertainties behind Pacific interannual and decadal-scale climate variability, and focuses on better understanding the roles of the CPW, NPO, and NPGO in the climate system.
The study begins by examining the dynamics of the NPO and its role in Pacific interannual and decadal climate variability. Results illustrate that the individual poles of the NPO have relations at high frequencies, but only the southern node contains a deterministic low-frequency component, which is forced by tropical Pacific sea surface temperature (SST) variability, as shown with a modeling experiment. The NPO-induced variability by the tropical Pacific SST is then integrated by the underlying ocean surface to form the decadal-scale NPGO signal. Thus, a new link between the CPW, the NPO, and the NPGO is formed, expanding the current framework of Pacific decadal variability and its implications for weather and climate.
The new framework of North Pacific decadal variability (NPDV) is then evaluated in 24 state-of-the-art coupled climate models. Results indicate that the models in general have difficulty reproducing the leading modes of NPDV in space and time, particularly the NPGO mode and its connection to the NPO. Furthermore, most models lack the proper connections between extratropical and tropical Pacific, for both the ENSO/AL/PDO and CPW/NPO/NPGO connections. Improvements in these teleconnections are thus needed to increase confidence in future climate projections.
The last part of the dissertation explores further the importance of the CPW mode by comparing and contrasting two popular paleoclimate SST anomaly reconstruction methods used for tropical Indo-Pacific SSTs. The first method exploits the high correlation between the canonical ENSO mode and tropical precipitation; the second method uses a multi-regression model that exploits the multiple modes of covariability between tropical precipitation and SSTs, including the CPW mode. The multi-regression approach demonstrates higher skill throughout the tropical Indo-Pacific than the first approach, illustrating the importance of including the CPW phenomenon in understanding past climates.
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Impactos das mudanças climáticas e do uso da terra nas perdas de solo da bacia hidrográfica do rio Piauitinga-SESantos, Robson Batista dos 22 February 2016 (has links)
Climate change and changes in the use and coverage of land, caused by human
activities, have been changing the soil loss in the Brazilians watershed. Therefore, this paper
estimated soil loss by extensive erosion in the watershed of the Piauitinga-SE river and
assessed the possible effects of climate change and land use and land cover over the loss of
soils in the basin. For this, we used the Universal Soil Loss Equation of (USLE) associated
with GIS and remote sensing techniques. Historical series were used (between 15 and 68
years) daily rainfall and data on climate projections coming from the Global Climate Model
(GCM), generated by the Community Climate System Model (CCSM) to the fourth
assessment report of the Intergovernmental Panel on Climate Change ( IPCC). In the
physiographic characteristics of the watershed, were used soil map, hydrographic network,
slope information and images of high spatial resolution of the RapidEye sensor to year 2013.
With this data, two estimates of soil loss were realized. The first estimate was considered two
scenarios for the watershed: Scenario 1 (C1) with physiographic and usage conditions and
current land cover; Scenario 2 (C2) with changes in land use and land cover, considering the
preserved the Permanent Preservation Areas (PPAs), as Law No. 12,651/2012. In the second
estimate it was considered four climate scenarios of rainfall: Current Scenario, Scenario
optimistic (Low B1), Scenario Medium (Medium A1B) and scenario Pessimistic (High A2),
and, for them, was only considered natural factors of erosion in the basin. In the first estimate,
the two scenarios (C1 and C2) of use and assessed land cover presented most of the basin area
with erosion between classes Very Low (0-5 ton-1.ha-1.year), Low ( 5-10 ton-1.ha-1.year) and
moderate (10-50 ton-1.ha-1.year). Considering the scenario 2, there was a reduction in soil loss
values, especially in the PPAs, proving the importance of maintaining these areas preserved
for conservation of soil and water in the basin. As for the second estimate, it was observed
that, when compared to the Current Scenario, the climate projections scenarios (Optimistic
B1, Medium A1B and Pessimistic A2) caused reduction of rainfall erosivity and soil loss in
the basin river Piauitinga - SE / As mudanças climáticas e as modificações no uso e cobertura da terra, provocadas
pela ação antrópica, vêm causando alterações nas perdas de solos das bacias hidrográficas
brasileiras. Portanto, este trabalho teve como objetivo principal estimar as perdas de solo por
erosão laminar na bacia hidrográfica do rio Piauitinga-SE e avaliar os possíveis impactos das
mudanças climáticas e do uso e cobertura da terra sobre as perdas dos solos na bacia. Para tal,
utilizou-se a Equação Universal de Perdas de Solo (USLE) associada à técnicas de
geoprocessamento e sensoriamento remoto. Foram utilizadas séries históricas (entre 15 e 68
anos) de precipitações diárias e dados de projeções climáticas oriundos do Global Climate
Model (GCM), gerados pelo Community Climate System Model (CCSM) para o quarto
relatório de avaliação do Painel Intergovernamental das Mudanças Climáticas (IPCC). Na
caracterização fisiográfica da bacia, foram utilizados mapas de tipo de solos, rede
hidrográfica, informações de relevo e imagens de alta resolução espacial do sensor RapidEye
do ano de 2013. De posse dos dados, foram realizadas duas estimativas de perdas de solo. Na
primeira estimativa foram considerados dois cenários para a bacia: Cenário 1 (C1), com as
condições fisiográficas e de uso e cobertura da terra atuais; Cenário 2 (C2) com alterações no
uso e cobertura da terra, considerando as Áreas de Preservação Permanentes Preservadas,
conforme Lei nº 12.651/2012. Na segunda estimativa foram avaliados quatro cenários
climáticos de precipitação pluviométrica: Cenário Atual, Otimista B1, Médio A1B e
Pessimista A2, sendo que, para estes, foram considerados apenas os fatores naturais de erosão
da bacia. Na primeira estimativa, os dois cenários (C1 e C2) de uso e cobertura da terra
avaliados apresentaram maior parte da área da bacia com erosão entre as classes Muito Baixa
(0-5 ton-1.ha-1.ano), Baixa (5-10 ton-1.ha-1.ano) e Moderada (10-50 ton-1.ha-1.ano).
Considerando o Cenário 2, houve uma redução nos valores de perda de solos, principalmente
nas APPs, comprovando a importância de manter estas áreas preservadas para a conservação
do solo e da água na bacia. Já para a segunda estimativa, foi observado que, quando
comparado ao Cenário Atual, os cenários de projeções climáticas (Otimista B1, Médio A1B e
Pessimista A2) provocaram redução da erosividade das chuvas e perdas de solo na bacia do
rio Piauitinga - SE.
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Why It Can Be Effective To Be Just When Sharing Climate Burdens / Varför Det Kan Vara Effektivt Att Vara Rättvis När Klimatbördan FördelasDecker, Carl-Otto January 2022 (has links)
This article aims to provide both efficient and just ways of sharing mitigative and adaptive climate burden costs. Time is an important factor when constructing policies which are set out to turn negative temperature trends around. Justice is another crucial value to consider when deciding who ought to carry out these climate burdens. Moreover, how we consider efficient and just sharing of burden costs, relies on practicality in relation to moral responsibility. Moral responsibility can be applied to those who have polluted and those who have benefitted from pollution. However, there are practical issues that hide between the lines. Justice grounded only on moral responsibility, such as ‘the polluter pays principle’ and ‘the beneficiary pays principle’, can only account for a limited portion of climate burdens. Because there are leftover burdens that need to be shared, and a climate window of opportunity to regard, we need to allocate the burdens both fairly as well as efficiently, such as ‘the ability to pay principle. In this paper, I will present a case that takes all of these dimensions into account and I will illustrate that it indeed can be effective to be just when sharing all climate burdens. / Denna artikel strävar efter att visa både effektiva och rättvisa sätt att fördela klimatbördan på. Denna börda innebär kostnaderna av att reducera utsläpp och anpassa samhället efter klimatförändringarna. Tid är en viktig faktor när vi konstruerar lagar och regler som syftar till att ändra riktning på den negativa temperaturutveckling forskare varnar oss för. Rättvisa är också en viktig komponent vi behöver ta hänsyn till när vi överväger vilka som bör axla klimatbördan. Hur vi överväger effektiva och rättvisa klimatfördelningar, beror på praktikalitet i relation till moraliskt ansvar. Moraliskt ansvar kan bland annat tillskrivas de som förorenar och de som gynnas av att förorena. Däremot finns det praktiska svårigheter som gömmer sig mellan raderna. Rättvisa som endast grundas på moraliskt ansvar, såsom ’förorenaren betalar’, ’den som gynnas av att förorena betalar’, kan enbart stå för en begränsad del av klimatbördan. Eftersom resterande börda också behöver fördelas blir vi tvungna att distribuera återstående börda både rättvist och effektivt, såsom ’de som2kan betala också ska’. I denna uppsats överväger jag dessa delar och kommer illustrera att det sannerligen är effektivt att vara rättvis när vi fördelar all klimatbörda.
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Reprezentace problému klimatických změn v tištěných médiích / Representation of the problem of climate change in the print mediaTrunečková, Daniela January 2015 (has links)
This diploma thesis on Representation of the problem of climate change in the print media is a content analysis of Czech quality daily newspapers, namely Hospodářské noviny, Lidové noviny, Mladá fronta DNES and Právo. It deals with the way the selected daily newspapers presented debate on global climate change in 2013-2014. The theoretical part informs readers about the basic concepts and definitions and introduces them to the problem. The empirical part answers the question of whether the media coverage of global climate change in Czech quality daily newspapers is consistent with scientific findings of the international climate discourse represented by Intergovernmental Panel on Climate Change (IPCC) or whether it relies equally on opinions of the small group of so called climate skeptics who question the general consensus of the scientific comunity regarding the causes and consequences of climate change or the need of adequate measures. The results of research indicated that most of analyzed articles informed about climate change the same way as the main climatological research. The largest number of skeptical articles appeared in Lidové noviny. A considerable number of articles didn't comment on the causes of climate change, their seriousness or decisions regarding action.
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Transportation system selection in open-pit mines (Truck-Shovel and IPCC systems) based on the technical, economic, environmental, safety, and social (TEcESaS) indexesAbbaspour, Hossein 12 January 2021 (has links)
The production of raw materials through mining projects is nowadays very challenging, mainly due to the rapid progress in the industrial and technological fields. On the one hand, they have to fulfill industries' requirements in their demand for materials while making a profit based on the current technologies. On the other hand, they should consider all other limitations, primarily environmental and social challenges that are confronting. The transportation system in any mining project is one of the most significant parts, especially in the technical and economic issues. It must transfer the planned volume of ore/waste that the whole stream of the mining process would not be interrupted and, it can cover the technical challenges and the costs imposed on the project. Additionally, it should be designed and selected to have the lowest environmental impact and the highest safety during the operation. Accordingly, a transportation system selection process that considers all these factors is one of the challenging issues in any mining project. Although the Truck-Shovel system is known as the conventional transportation in open-pit mines, which is preferable because of the low capital cost and high flexibility, it still imposes a high rate of operating costs, safety issues as well as environmental footprints. In-Pit Crushing and Conveying (IPCC) systems are the alternative transportation systems for the Truck-Shovel systems, in which the material is crushed inside the mine’s pit limit and transferred into the outside through conveyor belts. Although these systems are not new, they are mostly neglected as a transportation option basically due to the high capital cost and low flexibility. On the contrary, they can offer more environmentally friendly and safer working areas and a lower operating cost. According to these facts, each transportation system is preferable in a couple of technical, economic, environmental, safety, and social issues. Accordingly, in each circumstance, one or more of these systems can be used in the mining project. However, there is not yet a way or tool that investigates the transportation system selection along with the mine life that takes into account all of these factors.
To fill this gap, this project aims to define a model to introduce all these elements while it is interactively connected throughout the mine life. For this and as the first step, the system dynamics modeling is defined and used to build the model for all the technical, economic, environmental, safety, and social factors. As an output of this step, software entitled “TEcESaS Indexes” is designed and produced through Venapp that makes working with the model comfortable. As the second step, a selection method based on the Analytical Hierarchy Process (AHP) is performed that the transportation system selection regarding all the mentioned factors can be made. As the output in this step, the “Sustainability Index” software programmed in the Java language is developed. Considering a hypothetical copper open-pit mine as the case study and implementing the designed software, the results show although the Truck-Shovel system should be used in the first two years of the project (2016 and 2017) in the single expert and deterministic mode, the Fully Mobile In-Pit Crushing and Conveying (FMIPCC) system shows the highest sustainability index among other transportation systems from 2018 until the end of the mine life. While in the group decision making and deterministic simulation, the Truck-Shovel system should be utilized from 2016 to 2020. Additionally, in the group decision making and stochastic mode, the FMIPCC is the selected transportation system with the highest sustainability index probability.
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Parisavtalets inverkan på utsläppsrättigheter : En undersökning av handeln med utsläppsrätter och dess förenlighet med Parisavtalets klimatmål / The impact of the Paris agreement on emission rights : An analysis of emissions trading and its compatibility with the Paris Agreement’s objectiveEkstrand, Johan January 2022 (has links)
Syftet med uppsatsen är att undersöka nyttjande- och överlåtelserätten av utsläppsrätter samt om dessa kan inskränkas under åberopande av Parisavtalet. Parisavtalet är ett internationellt klimatavtal som trädde i kraft år 2016. Avtalet innebär huvudsakligen att ingående parter ska uppnå målet att begränsa den globala temperaturökningen till 1,5 grader Celsius, genom att minska utsläpp av växthusgaser. Avtalets målsättningar innebär inga skyldigheter för parterna, men trots det lades avtalet till grund för en nederländsk dom mot energikoncernen Shell år 2021. Domen innebär för Shell att minska utsläppen med 45 % fram till år 2030 i syfte att uppfylla Parisavtalet, vilket inskränker Shells utsläppsrättigheter. I artikel 3 utsläppshandelsdirektivet uttrycks att innehavaren av en utsläppsrätt har en rätt att släppa ut ett ton koldioxidekvivalenter. I artikel 12 utsläppshandelsdirektivet uttrycks att innehavaren har en rätt att överlåta utsläppsrätter till fysiska och juridiska personer inom unionen. När domen mot Shell inskränker nämnda artiklar, väcks intresset för dels hur exklusivt utsläppsrätter ägs, dels hur rätten att överlåta kan inskränkas. I Sverige regleras utsläppsrätter i lag (2020:1173) om vissa utsläpp av växthusgaser. Sverige har under lång tid framstått som en förebild i att visa resten av världen att man kan föra en offensiv klimat- och miljöpolitik och att fortsätta vara ett välfärdsland. Trots det, kommer Sverige under år 2022 inte lyckas uppfylla sin del av Parisavtalet om inte kraftigare minskningar genomförs, varför rättigheter om utsläpp kan komma att inskränkas även här. Kortfattat framgår följande av uppsatsen. Endast innehavandet av en utsläppsrätt innebär inte en juridisk rätt att släppa ut. För det erfordras tillstånd. Tillståndet är villkorat och utsläppsrätten måste nyttjas inom den tilldelade handelsperioden, vilket innebär att ett exklusivt ägande inte kan anses föreligga. Således uppfyller inte en utsläppsrätt Elgebrants villkor för begreppet egendom. Överlåtelserätten, som innebär en oinskränkt rätt att överlåta utsläppsrätter, faller emellertid under ett undantag vid tillämpning av Parisavtalet. Vidare har överlåtelserätten betydelse för statliga intäkter och företags överlevnad. En successiv minskning av växthusgaser är nödvändig för ett hållbart samhälle. Parisavtalet visar sig kunna inskränka nyttjande- och överlåtelserätten i Sverige under vissa förutsättningar. Försiktighetsprincipen, i 2 kap. 3 § miljöbalken, får även betydelse i frågan.
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全球氣候變遷治理中的美中關係 / The U.S.-China relations in global climate change governance黃憶如, Huang, Yi Ru Unknown Date (has links)
由於氣候變遷對全球帶來不可回復的危害，並成為影響國家安全的重要因素之一，聯合國自1988年起成立「政府間氣候變遷專門委員會」並啟動氣候治理談判，陸續於1992年及1997年通過《聯合國氣候變遷綱要公約》與《京都議定書》兩項協議，是現今全球應對此議題主要的兩項機制，透過每年召開締約方會議的方式進行協商，促進各締約方達成共識，提升全球節能減排的執行成效。
美國與中國的溫室氣體排放量在全球排名前二名，是已開發國家與開發中國家中具影響力的大國，故對氣候治理的立場與政策，成為影響全球節能減排成效的關鍵。然而由於氣候變遷議題涉及政治、經濟及安全利益，因此兩國對聯合國氣候治理機制所規範的「共同但有區別的責任原則」與減排份額規範的遵守，有各自的利益考量，在應對氣候變遷議題上，有衝突與摩擦，也有合作與實踐。
在聯合國所主導的氣候變遷治理機制中，美國與中國呈現競爭關係，但若跳脫此一機制，兩國反而能運用雙邊的交流協商，例如高層會談、簽署協議及戰略與經濟對話等平臺，進行雙邊合作達到自主的節能減排目標。從多邊的聯合國氣候談判機制與雙邊的交流分析，未來美中在應對氣候變遷議題上，仍將是既競爭又合作的關係。如果美國與中國能將現有積極進行雙邊合作立場推進到多邊的國際談判，減少已開發國家與開發中國家對氣候治理立場的分歧，那麼將能在國際氣候談判機制中發揮領導作用，促進新氣候協議的達成，對全球應對氣候變遷有極大的助益。 / Global climate change which has caused irreversible harm and become one of the important factors that affect international security, the United Nations set up Intergovernmental Panel on Climate Change （IPCC） in 1988 has held talks since then. After that United Nations Framework Convention on Climate Change（UNFCCC）and Kyoto Protocol（KP）were passed in 1992 and 1997 respectively, which are the world’s two main mechanisms to promote and enhance the implementation of effective emission reduction. The United States and China’s greenhouse gas emissions are the top two in the world and represent developed countries and developing countries. Their attitudes and policies of climate governance have become the key to the effective reduction in global greenhouse gas emissions. However, due to climate change issues related to political, economic and security interests, diffefent views on “common but differentiated responsibilities” and “responsibilities for emission reductions” give rise to both conflict and cooperation between the two countries.
In the United Nations-led climate change governance mechanisms, the United States holds a competitive relationship with China. But outside the mechanisms, their bilateral consultations, such as high-level talks, agreements and U.S.-China Strategic and Economic Dialogue （S&ED） help them achieve reduction targets. In the future, the U.S.-China relations on the climate change issue will continue to be both competitive and cooperative. If they can modify their stances through climate governance, it will be able to play a leadership role in international climate negotiations and promote the new climate agreement to solve global climate change issues effectvely.
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Reasons for the Underperformance of Clean Development Mechanism Project Activities in the Animal Waste Management Sector / An Analysis of Swine Manure treating Facilities in Latin America / Ursachen des geringen Erfolgs von Abwasserbehandlungsprojekten in der Tierproduktion im Rahmen des Clean Development Mechanism / Eine Analyse von Schweineproduktionsbetrieben in LateinamerikaDeecke, Imme Dorothea 04 February 2010 (has links)
No description available.
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