Combining AVHRR and ATSR satellite sensor data for operational boreal forest fire detection

The potential to combine data from two different satellite systems was studied to increase fire detection sensitivity and image acquisition frequency in real-time fire detection and fire control. A fully automatic fire detection algorithm was applied to all scenes that were acquired using both satellite systems. Local fire authorities were notified about each detected fire in their territory using real-time fire reports that were sent by telefax. The average time from the start of National Oceanic and Atmospheric Administration (NOAA), Advanced Very High Resolution Radiometer (AVHRR) image acquisition until the sending of a telefax fire report was 25 min. During the straw-burning season in April 2000, the Along Track Scanning Radiometer (ATSR) instrument detected twice as many fires as the AVHRR per unit image area. The main reason for this may be the average resolution cell of the ATSR, which is half the size of that of the AVHRR in terms of area. The response from fire authorities was used to estimate the number of correct alerts and false alarms. A false alarm rate of 12% and 7% was obtained in the fire seasons of 1999 and 2000, respectively.     

Airborne FTIR measurements over the Mt Etna volcano: preliminary results from the 2003 FASA Campaign

From 16 to 26 July 2003 an extensive field campaign was carried out around Mt Etna, Sicily, Italy. During the campaign a new airborne system, Fire Airborne Spectral Analyzer (FASA), was tested. The main instrument of the payload is a high resolution Michelson Interferometer with Rotating Retroreflector (MIROR), which operates in the nominal infrared 600–3000 cm^?1 spectral range with a high resolution of 0.12 cm^?1. This work investigates the feasibility of using MIROR data to retrieve the surface temperature, the hyper‐spectral emissivity and the SO₂ volcanic plume abundance. The results for the surface parameters show a good agreement with those obtained by satellite data and on ground measurements. In particular, the spectral emissivity shows a meaningful minimum, around 1040 cm^?1, consistent with the basaltic properties of Mt Etna's surface. A sensitivity study has also been carried out to show the difficulties of SO₂ columnar abundance retrieval due to the too low SO₂ volcanic emission and the too high instrumental noise.     

Ab initio correlation effects on the electronic and transport properties of metal(II)-phthalocyanine-based devices

Using first-principles calculations in the framework of density functional theory, we investigated the electronic and transport properties of metal(II)-phthalocyanine (M(II)Pc) systems, both in a single-molecule configuration and in a model device geometry. In particular, using copper(II)-Pc and manganese(II)-Pc as prototypical examples, we studied how electronic correlations on the central metal ion influence the analysis of the electronic structure of the system and we demonstrated that the choice of the exchange-correlation functional, also beyond the standard local or gradient corrected level, is of crucial importance for a correct interpretation of the data. Finally, our electronic transport simulations have shown that M(II)Pc-based devices can act selectively as molecular conductors, as in the case of copper, or as spin valves, as in the case of manganese, demonstrating once more the great potential of these systems for molecular nanoelectronics applications.     

Augmentation of nucleate boiling heat transfer and critical heat flux using nanoparticle thin-film coatings

Nanoparticle thin-film coatings applied to boiling surfaces using a layer-by-layer (LbL) assembly method demonstrated significant enhancement in the pool boiling critical heat flux (CHF) and nucleate boiling heat transfer coefficient. Up to 100% enhancement of the critical heat flux and over 100% enhancement of the heat transfer coefficient were observed for pool boiling of nickel wires coated with different thin-films of silica nanoparticles. Surface characterization revealed that the surface wettability changed drastically with the application of these coatings, while causing virtually no change in the surface roughness. It is concluded that the nanoporous structure coupled with the chemical constituency of these coatings leads to the enhanced boiling behavior.     

A virucidal face mask based on the reverse-flow reactor concept for thermal inactivation of SARS-CoV-2

While facial coverings reduce the spread of SARS-CoV-2 by viral filtration, masks capable of viral inactivation by heating can provide a complementary method to limit transmission. Inspired by reverse-flow chemical reactors, we introduce a new virucidal face mask concept driven by the oscillatory flow of human breath. The governing heat and mass transport equations are solved to evaluate virus and CO₂ transport. Given limits imposed by the kinetics of SARS-CoV-2 thermal inactivation, human breath, safety, and comfort, heated masks may inactivate SARS-CoV-2 to medical-grade sterility. We detail one design, with a volume of 300 ml at 90°C that achieves a 3-log reduction in viral load with minimal impedance within the mask mesh, with partition coefficient around 2. This is the first quantitative analysis of virucidal thermal inactivation within a protective face mask, and addresses a pressing need for new approaches for personal protective equipment during a global pandemic.     

Non-linear matrix modeling of forest growth with permanent plot data: The case of uneven-aged Douglas-fir stands

Uneven‐aged forest management is acquiring increasing importance throughout the world as an alternative to clear cutting. Simple stage‐structured matrix models can be used to predict the growth of uneven‐aged stands, and they are easily incorporated in optimization analysis. Parameters of these models can be estimated from readily available permanent plot data. Such a growth and yield model is presented for mixed, uneven‐aged Douglas‐fir and hardwood stands. The model was calibrated with data from 66 permanent plots in Oregon and Washington. The density‐dependent matrix model predicts the number of trees by diameter class and species type, softwood or hardwood. The parameters are based on individual tree growth equations, individual tree mortality equations, and stand ingrowth equations. The individual tree equations are a function of tree diameter, stand density, species, and site index. The stand‐level ingrowth equations are a function of stand density. The model was validated in the short term by comparing the number of trees in each diameter and species class at the time of the second inventory with the number predicted by the model, given conditions at the first inventory. A long‐term validation of the model was also done by comparing the steady‐state stand structure and stand volume with those observed for old‐growth stands. The model was applied to show the effects of different cutting cycles on productivity, diversity of tree species and size, and financial returns. The results suggest that uneven‐aged management of the Douglas‐fir forest type in the Pacific Northwest can be as productive as even‐aged management, with the added benefits of continuous cover forestry.     

Remote mobile manipulation with the centauro robot: Full‐body telepresence and autonomous operator assistance

Solving mobile manipulation tasks in inaccessible and dangerous environments is an important application of robots to support humans. Example domains are construction and maintenance of manned and unmanned stations on the moon and other planets. Suitable platforms require flexible and robust hardware, a locomotion approach that allows for navigating a wide variety of terrains, dexterous manipulation capabilities, and respective user interfaces. We present the CENTAURO system which has been designed for these requirements and consists of the Centauro robot and a set of advanced operator interfaces with complementary strength enabling the system to solve a wide range of realistic mobile manipulation tasks. The robot possesses a centaur‐like body plan and is driven by torque‐controlled compliant actuators. Four articulated legs ending in steerable wheels allow for omnidirectional driving as well as for making steps. An anthropomorphic upper body with two arms ending in five‐finger hands enables human‐like manipulation. The robot perceives its environment through a suite of multimodal sensors. The resulting platform complexity goes beyond the complexity of most known systems which puts the focus on a suitable operator interface. An operator can control the robot through a telepresence suit, which allows for flexibly solving a large variety of mobile manipulation tasks. Locomotion and manipulation functionalities on different levels of autonomy support the operation. The proposed user interfaces enable solving a wide variety of tasks without previous task‐specific training. The integrated system is evaluated in numerous teleoperated experiments that are described along with lessons learned.