862 research outputs found

    ART-SLAM: Accurate Real-Time 6DoF LiDAR SLAM

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    Real-time six degrees-of-freedom pose estimation with ground vehicles represents a relevant and well-studied topic in robotics due to its many applications such as autonomous driving and 3D mapping. Although some systems already exist, they are either not accurate or they struggle in real-time settings. In this letter, we propose a fast, accurate and modular LiDAR SLAM system for both batch and online estimation. We first apply downsampling and outlier removal, to filter out noise and reduce the size of the input point clouds. Filtered clouds are then used for pose tracking, possibly aided by a pre-tracking module, and floor detection, to ground optimize the estimated trajectory. Efficient multi-steps loop closure and pose optimization, achieved through a g2o pose graph, are the last steps of the proposed SLAM pipeline. We compare the performance of our system with state-of-the-art point cloud-based methods, LOAM, LeGO-LOAM, A-LOAM, LeGO-LOAM-BOR, LIO-SAM and HDL, and show that the proposed system achieves equal or better accuracy and can easily handle even cases without loops. The comparison is done evaluating the estimated trajectory displacement using the KITTI (urban driving) and Chilean (underground mine) datasets

    Geothermal Potential Evaluation for Northern Chile and Suggestions for New Energy Plans

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    Chile is a country rich in natural resources, and it is the world’s largest producer and exporter of copper. Mining is the main industry and is an essential part of the Chilean economy, but the country has limited indigenous fossil fuels—over 90% of the country’s fossil fuels must be imported. The electricity market in Chile comprises two main independent systems: the Northern Interconnected Power Grid (SING) and the Central Interconnected Power Grid (SIC). Currently, the primary Chilean energy source is imported fossil fuels, whereas hydropower represents the main indigenous source. Other renewables such as wind, solar, biomass and geothermics are as yet poorly developed. Specifically, geothermal energy has not been exploited in Chile, but among all renewables it has the greatest potential. The transition from thermal power plants to renewable energy power plants is an important target for the Chilean Government in order to reduce dependence on imported fossil fuels. In this framework, the proposed study presents an evaluation of the geothermal potential for northern Chile in terms of power generation. The El Tatio, Surire, Puchuldiza, Orriputunco-Olca and Apacheta geothermal fields are considered for the analysis. The estimated electrical power is approximately 1300 MWe, and the energy supply is 10,200 GWh/year. This means that more than 30% of the SING energy could be provided from geothermal energy, reducing the dependence on imported fossil fuels, saving 8 Mton/year of CO2 and supplying the mining industry, which is Chile’s primary energy user

    China\u27s Investments and Land Use in Latin America

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    Increased demand by China for commodities has impacted natural resources and local people in Latin America, at a time when climate change has created an urgency for sustainable practices. This report aims to contribute to a nuanced view of Chinese major investments and trade, analyzing the soy, copper, and beef industries. In many cases, it shows how unsustainability is not the result of the practices of Chinese companies but rather the nature of the resource, local legal frameworks, or global industry standards. Latin American countries must devise development plans for these industries and not rely solely on voluntary sustainability standards adopted by the private sector to preserve Latin America\u27s vulnerable ecosystems in light of climate change.https://digitalcommons.fiu.edu/jgi_research/1048/thumbnail.jp

    The long run development of Chile and the Natural Resources curse. Linkages, policy and growth, 1850-1950

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    This chapter analyses the effects of Natural Resources on the Chilean economy in the long run -1850-1950-. Specifically, the authors focus their attention on the mining cycles -nitrates and copper- and their impact on the mining activity. We also compare it with the evolution of the industry and whole economy, and how this has affected the economic growth of the country. In that sense, the industrial performance in Chile at the end of the 19th century until the Great Depression is still under debate. The optimistic view of Kirsch -1977- forehead the pessimistic view of Lagos -1966- and Palma -1979-. The new data and its analyses shows a neutral effect of the Natural Resources in the industrial development

    SIMULACIJA DOSTUPNOSTI I ANALIZA RADA OKLOPNOGA TRANSPORTERA U ŠIROKOČELNOME RUDARENJU

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    Since coal mining production systems are very complex, repairing equipment is expensive. If a system failure occurs, it will cause disturbances such as inoperable equipment, reduced operating time, increased production costs, and reduced equipment performance. Therefore, it is necessary to consider the availability of the coal mining industry more than ever. For this purpose, the Armored Face Conveyor (AFC) machine failure data was gathered over a period of 29 months from the Tabas Coal Mine. Descriptive statistics, trends, and serial correlation tests of the data were calculated. Then, the system’s mean and point availability were simulated. Based on the results, the mean availability (all events) and point availability (all events) at 360000 h are 96% and 95%, respectively. The mean time to first failure (MTTFF) of the AFC machine was about 23.61 h. The ReliaSoft Failure Criticality Index, ReliaSoft Downing Event Criticality Index, and ReliaSoft Downtime Criticality Index electrical equipping have the largest effect, whereas the main drive subsystem is the least important. Analysis showed that availability has a direct correlation to activity management and improvements in the quality, efficiency, and the product extraction.Sustavi proizvodnje ugljena u rudnicima vrlo su složeni, stoga je i popravak opreme skup. Kvar sustava uzrokovat će smetnje kao što je nedostupna oprema, smanjeno vrijeme rada, povećani troškovi proizvodnje i smanjene performanse opreme. Stoga je nužno da se dostupnost industrije ugljena razmatra više nego ikad. U tu svrhu 29 mjeseci prikupljani su podatci o kvaru stroja tipa oklopljenoga širokočelnoga transportera iz rudnika ugljena Tabas. Izračunane su opisna statistika, trendovi i test serijske korelacije podataka. Zatim su simulirane srednje vrijednosti i dostupnost bodova u sustavu. Na temelju rezultata prosječna dostupnost (svi događaji) i dostupnost točke (svi događaji) na 360 000 h iznose 96 % odnosno 95 %. Prosječno je vrijeme do prvoga kvara (MTTFF) transportnog stroja oko 23,61 h. U trima metričkim vrijednostima, ReliaSoft indeksu kritičnosti kvara, ReliaSoft indeksu kritičnosti pada sustava i ReliaSoft indeksu kritičnosti zastoja, električno opremanje ima najveći učinak, dok je glavni pogonski podsustav najmanje važan. Utvrđeno je da analiza dostupnosti kontrolira upravljanje operacijama i poboljšanja u kvaliteti, učinkovitosti i izvedbi linije
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