The field of 3D face modeling has a large gap between high-end and low-end methods. At the high end, the best facial animation is indistinguishable from real humans, but this comes at the cost of ...extensive manual labor. At the low end, face capture from consumer depth sensors relies on 3D face models that are not expressive enough to capture the variability in natural facial shape and expression. We seek a middle ground by learning a facial model from thousands of accurately aligned 3D scans. Our FLAME model (Faces Learned with an Articulated Model and Expressions) is designed to work with existing graphics software and be easy to fit to data. FLAME uses a linear shape space trained from 3800 scans of human heads. FLAME combines this linear shape space with an articulated jaw, neck, and eyeballs, pose-dependent corrective blendshapes, and additional global expression blendshapes. The pose and expression dependent articulations are learned from 4D face sequences in the D3DFACS dataset along with additional 4D sequences. We accurately register a template mesh to the scan sequences and make the D3DFACS registrations available for research purposes. In total the model is trained from over 33, 000 scans. FLAME is low-dimensional but more expressive than the FaceWarehouse model and the Basel Face Model. We compare FLAME to these models by fitting them to static 3D scans and 4D sequences using the same optimization method. FLAME is significantly more accurate and is available for research purposes (http://flame.is.tue.mpg.de).
Human motion modelling is a classical problem at the intersection of graphics and computer vision, with applications spanning human-computer interaction, motion synthesis, and motion prediction for ...virtual and augmented reality. Following the success of deep learning methods in several computer vision tasks, recent work has focused on using deep recurrent neural networks (RNNs) to model human motion, with the goal of learning time-dependent representations that perform tasks such as short-term motion prediction and long-term human motion synthesis. We examine recent work, with a focus on the evaluation methodologies commonly used in the literature, and show that, surprisingly, state of the art performance can be achieved by a simple baseline that does not attempt to model motion at all. We investigate this result, and analyze recent RNN methods by looking at the architectures, loss functions, and training procedures used in state-of-the-art approaches. We propose three changes to the standard RNN models typically used for human motion, which results in a simple and scalable RNN architecture that obtains state-of-the-art performance on human motion prediction.
Learning from Synthetic Humans Varol, Gul; Romero, Javier; Martin, Xavier ...
2017 IEEE Conference on Computer Vision and Pattern Recognition (CVPR),
2017-July
Conference Proceeding
Odprti dostop
Estimating human pose, shape, and motion from images and videos are fundamental challenges with many applications. Recent advances in 2D human pose estimation use large amounts of manually-labeled ...training data for learning convolutional neural networks (CNNs). Such data is time consuming to acquire and difficult to extend. Moreover, manual labeling of 3D pose, depth and motion is impractical. In this work we present SURREAL (Synthetic hUmans foR REAL tasks): a new large-scale dataset with synthetically-generated but realistic images of people rendered from 3D sequences of human motion capture data. We generate more than 6 million frames together with ground truth pose, depth maps, and segmentation masks. We show that CNNs trained on our synthetic dataset allow for accurate human depth estimation and human part segmentation in real RGB images. Our results and the new dataset open up new possibilities for advancing person analysis using cheap and large-scale synthetic data.
Global warming is increasingly affecting our biosphere. However, in addition to global warming, a panoply of local stressors caused by human activities is having a profound impact on our environment. ...The risk that these local stressors could modify the response of organisms to global warming has attracted interest and fostered research on their combined effect, especially with a view to identifying potential synergies. In coastal areas, where human activities are heavily concentrated, this scenario is particularly worrying, especially for foundation species such as seagrasses. In this study we explore these potential interactions in the seagrass Posidonia oceanica. This species is endemic to the Mediterranean Sea. It is well known that the Mediterranean is already experiencing the effects of global warming, especially in the form of heat waves, whose frequency and intensity are expected to increase in the coming decades. Moreover, this species is especially sensitive to stress and plays a key role as a foundation species. The aim of this work is thus to evaluate plant responses (in terms of photosynthetic efficiency and growth) to the combined effects of short-term temperature increases and ammonium additions.To achieve this, we conducted a mesocosm experiment in which plants were exposed to three thermal treatments (20°C, 30°C and 35°C) and three ammonium concentrations (ambient, 30 μM and 120 μM) in a full factorial experiment. We assessed plant performance by measuring chlorophyll fluorescence variables (maximum quantum yield (Fv/Fm), effective quantum yield of photosystem II (ΔF/Fm'), maximum electron transport rate (ETRmax) and non-photochemical quenching (NPQ)), shoot growth rate and leaf necrosis incidence. At ambient ammonium concentrations, P. oceanica tolerates short-term temperature increases up to 30°C. However, at 35°C, the plant loses functionality as indicated by a decrease in photosynthetic performance, an inhibition of plant growth and an increase of the necrosis incidence in leaves. On the other hand, ammonium additions at control temperatures showed only a minor effect on seagrass performance. However, the combined effects of warming and ammonium were much worse than those of each stressor in isolation, given that photosynthetic parameters and, above all, leaf growth were affected. This serves as a warning that the impact of global warming could be even worse than expected (based on temperature-only approaches) in environments that are already subject to eutrophication, especially in persistent seagrass species living in oligotrophic environments.
Today, ≈20% of the electric consumption is devoted to refrigeration; while, ≈50% of the final energy is dedicated to heating applications. In this scenario, many cooling devices and heat‐pumps are ...transitioning toward the use of CO2 as an eco‐friendly refrigerant, favoring carbon circular economy. Nevertheless, CO2 still has some limitations, such as large operating pressures (70–150 bar) and a critical point at 31 °C, which compromises efficiency and increases technological complexity. Very recently, an innovative breathing‐caloric mechanism in the MIL‐53(Al) compound is reported, which implies gas adsorption under CO2 pressurization boosted by structural transitions and which overcomes the limitations of stand‐alone CO2. Here, the breathing‐caloric‐like effects of MOF‐508b are reported, surpassing by 40% those of MIL‐53(Al). Moreover, the first thermometry device operating at room temperature and under the application of only 26 bar of CO2 is presented. Under those conditions, this material presents values of ΔT ≈ 30 K, reaching heating temperatures of 56 °C and cooling temperatures of −10 °C, which are already useful for space heating, air‐conditioning, food refrigeration, and freezing applications.
MOF‐508b displays enhanced breathing‐caloric‐like effects related to two consecutive phase transitions, where barocaloric effects and sorption thermal changes coexist. Moreover, the first thermometry device to characterize this type of thermomaterials is presented, where MOF‐508b shows remarkable temperature changes of 30 K under CO2 pressurization of only 26 bar, which can empower existing CO2 heating and cooling systems.
Review of propulsion systems on LNG carriers Fernández, Ignacio Arias; Gómez, Manuel Romero; Gómez, Javier Romero ...
Renewable & sustainable energy reviews,
January 2017, 2017-01-00, Letnik:
67
Journal Article
Recenzirano
Vessel ozone depleting emission regulations are regulated in Annex VI of the MARPOL Convention, wherein the maximum levels of NOx, SOx and suspended particles are established. These increasingly ...strict regulations, together with the increase in natural gas consumption and its price, have conditioned propulsion systems implemented on board vessels.
This article reviews the different propulsion systems used on board vessels for the transport of Liquefied Natural Gas (LNG). The study describes the main characteristics of the propulsion systems, and the advantages and drawbacks that come along with these, from its very beginnings up to the systems installed to date. The described propulsion systems include both gas and steam turbines, combined cycles, 2 and 4 stroke internal combustion engines, as well as reliquefaction plants, while encompassing mechanical, electric and Dual Fuel (DF) technology systems.
The propulsion systems implemented have undergone continual alteration in order to adjust to market needs, which were always governed by both efficiency and the possibility of consuming boil-off gas (BOG), always in compliance with the strict antipollution regulations in force.
The current direction of LNG vessel propulsion systems is the installation of 2-stroke DF low pressure engines due to their high efficiency and their possibility of installing a BOG reliquefaction plant. Another great advantage of this propulsion system is its compliance with the IMO TIER III emission regulations, without the need to install any supplementary gas treatment system.
Forest are highly vulnerable to global change drivers, such as an increase in wildfire events. Learning more about how and why different post‐fire management strategies regulate the ability of forest ...ecosystem properties (e.g. plant diversity and function) to simultaneously recover after wildfire and provide multiple ecosystem functions is of critical importance.
This study aims to evaluate how unburned, burned managed and burned unmanaged plots regulate the responses of multiple forest ecosystem properties (e.g. plant diversity, nutrient cycling, soil carbon stocks, water regulation, decomposition and wood production) and overall multifunctionality to wildfires. In September 2017, we selected two post‐fire management strategies in a 3‐km2 watershed previously affected by a wildfire in July 2012: contour‐felled log debris (CFD), log erosion barriers area (LEB), and also unburned and unmanaged plots (BNA). We randomly distributed 12 plots among the three post‐fire management strategies (three plots per treatment) and unburned.
The results showed that multiple forest ecosystem properties were significantly affected by wildfire and that specific post‐fire management treatment (e.g. LEB and CFD) can be used to efficiently support plant diversity and ecosystem functioning. Our results revealed that the general indicators of ecosystem functions decreased in Mediterranean forests after wildfires and post‐fire management strategies (LEB and CFD) significantly helped to recover the ecosystems’ short‐term community‐level properties and ecosystem functions (5 years after a wildfire event) to pre‐fire levels.
Synthesis and applications. These findings demonstrate that multiple ecosystem functions are affected by wildfires in Mediterranean forests and show that post‐fire management treatments can promote multifunctionality and plant diversity. Our results unfold the potential of log erosion barriers (LEB) and contour‐felled log debris (CFD) as effective strategies for recovering community‐level properties and forest functions in the short term.
These findings demonstrate that multiple ecosystem functions are affected by wildfires in Mediterranean forests and show that post‐fire management treatments can promote multifunctionality and plant diversity. Our results unfold the potential of log erosion barriers (LEB) and contour‐felled log debris (CFD) as effective strategies for recovering community‐level properties and forest functions in the short term.
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