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European legal framework related to underground mining and tunnelling concerning commission directive (EU) 2017/164, 31 January establishing a fourth list of indicative occupational exposure limit values

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International Journal of Mining Science and Technology 2020年第4期30卷 541-545页

作者： miguel Tato Diogo Department of Mining Engineering Faculty of EngineeringUniversity of PortoPorto 4200-465Portugal

Directive(EU)2017/164 establishes a fourth list of indicative occupational exposure limit values(IOELVs)to protect workers from risks of exposure to hazardous *** states that in underground mining and tunnelling,Member States may benefit from a transitional period regarding IOELVs for nitrogen monoxide,nitrogen dioxide,and carbon monoxide,during which the existing established IOELVs may be *** European Advisory Committee on Health and Safety at Work questions the technical feasibility of the proposed IOELVs in underground mining(CO,NO and NO2)and tunnelling(NO and NO2).Challenges arise concerning the availability of measurement methodologies for compliance with proposed IOELVs(NO2)in underground mining and tunnelling environments.

关键词： Nitrogen monoxide Nitrogen dioxide Carbon monoxide IOELVs European Directive 2017/164 Underground mining Tunnelling

Cities and Methods from Complexity Science

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Journal of Systems Science & Complexity 2016年第5期29卷 1177-1186页

作者： BALMACEDA Beatriz FUENTES miguel CIDES Corpotraining Av. Providencia 2370 Santiago Chile Santa Fe Institute 1399 Hyde Park Road Santa Fe New Mexico 87501 USA IIF-Sadaf/CONICET Bulnes 642 Buenos Aires 1176 Argentina Facultad de Ingenieria y Tecnologla Universidad San Sebastidn Lota 2465 Santiago 7510157 Chile

The dynamics of human society is now been studying in the context of the artificial environment created by cities. In this work, the authors describe some of the formal methods used in complexity science to study urban systems. The authors discuss some of the important quantitative approaches on cities paying attention to some of the deepest controversies in present scientific *** authors will stress the importance of a transdisciplinary approach when studying this type of cooperative social environments.

关键词： Cities complexity environment.

Reflection of Short Waves

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China Ocean Engineering 1999年第1期14卷 31-46页

作者： miguel A. LOSADA University of Cantabria

According to the; energy equation, the relation between reflection and energy losses for short waves from mild beaches is established and analysed. A reflection coefficient varying with position and energy losses is proposed. Different reflection tests are conducted to check the theoretical analysis. A modified method to estimate the reflection coefficient at varied water depths is suggested based on the linear wave theory. The study indicates that the reflection coefficient from mild beaches has a changing trend for short waves approaching shoreline.

关键词： reflection incident wave reflected wave short wave

Induced pluripotent stem cell (iPS) technology:promises and challenges

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Chinese Science Bulletin 2009年第1期54卷 2-8页

作者： miguel A Esteban Laboratory of Regenerative Biology South China Institute for Stem Cell Biology and Regenerative MedicineGuangzhou Institute of Biomedicine and HealthChinese Academy of Sciences

In 2006,an article published in Cell by Shinya Yamanaka took by surprise the stem cell research community. By performing systematic retroviral transduction of factors enriched in embryonic stem (ES) cells,the authors demonstrated the reprogramming of mouse fibroblasts into an ES cell-like state. These cells,baptized iPS (induced pluripotent stem) cells,were immediately recognized as a ground-breaking discovery. Subsequently,the same authors and other groups reported a similar achievement with human fibroblasts. Two years later,the number of top quality papers on iPS is astonishing,and interest in the scientific community has risen to a fever pitch. But although iPS has the potential to revolutionize Regenerative Medicine,important questions still remain unanswered. Work from multiple laboratories worldwide including ours is focused on deciphering the molecular mechanisms of iPS,and trying to improve the technique to make it suitable for the clinic. In this review article we briefly discuss the past,present and future of iPS,with emphasis on urgent issues to be solved.

关键词：自身更新多能性胚胎干细胞多能干细胞

Auctions to reveal consumers’willingness to pay for low-carbon hydrogen projects:combining lessons from renewables and natural-gas industries

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Clean Energy 2024年第4期8卷 103-110页

作者： miguel Vazquez Michelle Hallack SDA School of Management Bocconi UniversityVia Roberto Sarfatti1020136 MilanMIItaly Florence School of Regulation EUIVia Giovanni Boccaccio12150133 FirenzeFIItaly

Low-carbon hydrogen is expected to play a key role in realizing net-zero and sustainable development ***,there is a gap between the cost of producing low-carbon hydrogen and its potential users’willingness to pay for such *** implement support for the development of the industry,we propose using low-carbon hydrogen long-term agreements allocated through auction *** objectives are 2-fold:(i)matching supply and demand volumes considering the time horizon and geographical delivery point specification and(ii)allocating the *** perspective article innovates by proposing a reference price indexed to liquid to natural-gas prices,which is the main product that low-carbon hydrogen aims to *** premium and the production cost are defined through a double-sided *** aims to minimize the public policy funds required to incentivize the low-carbon hydrogen market while facilitating long-term agreements and mitigating price risks that may hinder investment.

关键词： hydrogen auctions Renewable Eenergy Systems support mechanisms natural gas

A flexible lag definition for experimental variogram calculation

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Mining Science and Technology 2011年第2期21卷 207-211页

作者： Cuba miguel Centre of Computational Geostatistics School of Petroleum and Mining EngineeringUniversity of Alberta

Inferring the experimental variogram used in geostatistics commonly relies on the method-of-moments ***,the available data-set used for calculating the experimental variogram should be drawn from a regular ***,in practice the available data-set is typically sampled over a sparse pattern at irregularly spaced ***,some binning of the variogram cloud is required to obtain fair estimates of the experimental *** of the variogram data pairs as a result of conventional binning depends on parameters such as the main anisotropic directions and a regular definition of the lag *** parameters are not based on the configuration of the variogram data pairs in the variogram cloud but on a segment of it that is arbitrarily ***,the conventional experimental variogram estimation approach is biased because of the strict configuration of the bins over the variogram *** this paper,a new method of estimating experimental variograms is *** vectors and their tolerances are decided in the proposed method from information in the variogram cloud：they are not influenced by any predefined *** proposed methodology is a well-founded,practicable and easy-to-automate approach for experimental variogram calculation using an irregularly sampled *** of results from the new method to those from the traditional approach is very encouraging.

关键词： Geostatistics Variogram cloud Experimental variogram Variogram modeling Self-organizing-map

Characterization of the Topography and Wettability of English Weed Leaves and Biomimetic Replicas

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Journal of Bionic Engineering 2014年第3期11卷 346-359页

作者： Pedro miguel Matos Pereira Ana Sofia Moita Gabriel Amaro Monteiro Duarte miguel Franca Prazeres IBB - Institute for Biotechnology and Bioengineering Centre for Biological and Chemical Engineering Department of Bioengineering Instituto Superior Tecnico Universidade de Lisboa Av. Rovisco Pals 1049-001 Lisboa Portugal IN+ - Center for Innovation Technology and Policy Research Instituto Superior T~cnico Universidade de Lisboa Av. Rovisco Pais 1049-001 Lisboa Portugal

The topography and wettability of the underside of English weed （Oxalis pes-caprae） leaves and of their biomimetic replicas are investigated. Polyvinyl siloxane molds were cast from the leaves and then filled with an epoxy pre-polymer to produce replicas. The particular topographical structures of leaves and replicas were evaluated by optical microscopy and Scanning Electron Microscopy （SEM） analysis. The static wettability of leaves and replicas was assessed by contact angle measurements, while the dynamic wettability was characterized by estimating contact angle hysteresis and studying the dynamic behavior of impacting water droplets. A smooth glass slip and its replica were used as control surfaces. The replica moulding method used was able to transfer the characteristic pattern of irregular 100 μm - 200 μm × 60 μm convex papillae interspersed with stomata of the original leaf to the epoxy replicas. The static contact angle of 143°± 3° and the contact angle hysteresis of 2~ indicate that the underside of the English weed leaf is close to superhydrophobic. The lower contact angles （130° ± 4°） and higher hysteresis （31°） observed for the replica when compared with the original leaves were associated to an inaccurate replication of the chemistry and structures of the three-dimensional wax projections covering the plant surface. Also, trichomes in the original leaves could not be accurately reproduced due to their flexibility and fragility. Differences in wetting behavior were also evident from droplet impact experiments, with rebound regimes prevailing in the original leaves and regimes characterized by higher adhesion and larger dissipation predominating in the replicas. Nevertheless, the morphological features of the leaf transferred to the replica were sufficient to promote a clear hydrophobic behavior of the replica when compared with the smooth epoxy reference surface.

关键词： biomimetic surfaces oxalis pes-caprae English weed replica molding wettability micro-topography

Science Letters:Blind spot detection using vision for automotive applications

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第10期9卷 1369-1372页

作者： miguel ngel SOTELO José BARRIGA Department of Electronics University of Alcalá Alcalá de Henares 28871 Spain

This paper describes a vision-based system for blind spot detection (BSD) in intelligent vehicle applications. A camera is mounted in the lateral mirror of a car with the intention of visually detecting cars that are located in the so-called blind spot and cannot be perceived by the vehicle driver. The detection of cars in the blind spot is carried out using computer vision techniques, based on optical flow and a double-stage data clustering technique for robust vehicle detection.

关键词： Computer vision Optical flow Blind spot detection (BSD) Intelligent vehicles

Plumbing System of Hunga Tonga Hunga Ha'apai Volcano

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Journal of Earth Science 2023年第3期34卷 706-716页

作者： Román Alvarez miguel Camacho Instituto de Investigaciones en Matemáticas Aplicadas y en Sistemas(IIMAS) Universidad Nacional Autónoma de MéxicoCoyoacán CDMX 04510Mexico Posgrado en Ciencias de la Tierra Universidad Nacional Autónoma de MéxicoCoyoacán CDMX 04510Mexico

The Hunga Tonga Hunga Ha’apai submarine volcano has experienced repeated eruptions in the latest *** recent one,in January 2022,released an enormous amount of energy inducing global perturbations,as tsunamis and atmospheric *** structure of the volcano is poorly understood,especially its internal ***-seated magmatic connections are difficult to define or *** use a high-resolution gravity data set obtained via satellite to calculate the Bouguer anomaly over its structure,to perform a preliminary exploration of its *** 3D gravity inversions,we find a complex plumbing system with various exhaust trajectories and multiple surface pockets of low-density material within the volcanic edifice;some appear to be associated with ring *** is in line with the report of the 2009 eruption,described as beginning from multiple *** found no signs of a magma chamber within 6 km depth,although several volcanic conduits are identified from such depth to the *** variations occur within a plumbing conduit or may vary from one conduit to another in the same *** models yield quantitative estimates for areas of magma-water interaction,constituting a baseline to compare with structural changes to be induced in future eruptions.

关键词： Hunga Tonga Hunga Ha'apai satellite gravity data 3D inversions volcano Tofua Island