110 research outputs found
Usage of Data-Encoded Web Maps with Client Side Color Rendering for Combined Data Access, Visualization and Modeling Purposes
Current approaches to satellite observation data storage and distribution implement separate visualization and data access methodologies which often leads to the need in time consuming data ordering and coding for applications requiring both visual representation as well as data handling and modeling capabilities. We describe an approach we implemented for a data-encoded web map service based on storing numerical data within server map tiles and subsequent client side data manipulation and map color rendering. The approach relies on storing data using the lossless compression Portable Network Graphics (PNG) image data format which is natively supported by web-browsers allowing on-the-fly browser rendering and modification of the map tiles. The method is easy to implement using existing software libraries and has the advantage of easy client side map color modifications, as well as spatial subsetting with physical parameter range filtering. This method is demonstrated for the ASTER-GDEM elevation model and selected MODIS data products and represents an alternative to the currently used storage and data access methods. One additional benefit includes providing multiple levels of averaging due to the need in generating map tiles at varying resolutions for various map magnification levels. We suggest that such merged data and mapping approach may be a viable alternative to existing static storage and data access methods for a wide array of combined simulation, data access and visualization purposes
Improvements of CO2 and O2 Transmission Modeling for ASCENDS Mission Applications
Simulations using the HITRAN database and other data have been carried out to select the optimum laser wavelengths for the measurements of CO2 and O2 concentrations with the application to the ASCENDS mission. The accuracy set forth for the ASCENDS mission requires accurate line-by-line calculations involving the use of non-Voigt line shapes. To aid in achieving this goal, improved CO2 and O2 transmission calculation methods are being developed. In particular, line-by-line transmission modeling of CO2 was improved by implementing non-Voigt spectral lineshapes. Ongoing work involves extending this approach to the O2 molecule 1.26-1.27micron spectral band
New Technology for Microfabrication and Testing of a Thermoelectric Device for Generating Mobile Electrical Power
We report the results of fabrication and testing of a thermoelectric power generation module. The module was fabricated using a new "flip-chip" module assembly technique that is scalable and modular. This technique results in a low value of contact resistivity ( < or = 10(exp 5) Ohms-sq cm). It can be used to leverage new advances in thin-film and nanostructured materials for the fabrication of new miniature thermoelectric devices. It may also enable monolithic integration of large devices or tandem arrays of devices on flexible or curved surfaces. Under mild testing, a power of 22 mW/sq cm was obtained from small (<100 K) temperature differences. At higher, more realistic temperature differences, approx.500 K, where the efficiency of these materials greatly improves, this power density would scale to between 0.5 and 1 Watt/cm2. These results highlight the excellent potential for the generation and scavenging of electrical power of practical and usable magnitude for remote applications using thermoelectric power generation technologies
A Fully Automated Approach to Segmentation of Irregularly Shaped Cellular Structures in EM Images
While there has been substantial progress in segmenting natural im-ages, state-of-the-art methods that perform well in such tasks unfortunately tend to underperform when confronted with the different challenges posed by electron microscope (EM) data. For example, in EM imagery of neural tissue, numerous cells and subcellular structures appear within a single image, they exhibit irregular shapes that cannot be easily modeled by standard techniques, and confusing textures clutter the background. We propose a fully automated approach that handles these challenges by using sophisticated cues that capture global shape and texture information, and by learning the specific appearance of object boundaries. We demonstrate that our approach significantly outperforms state-of-the-art techniques and closely matches the performance of human annotators
A mitochondrial-targeted cyclosporin A with high binding affinity for cyclophilin D yields improved cytoprotection of cardiomyocytes
Mitochondrial CyP-D (cyclophilin-D) catalyses formation of the PT (permeability transition) pore, a key lesion in the pathogenesis of I/R (ischaemia/reperfusion) injury. There is evidence [Malouitre, Dube, Selwood and Crompton (2010) Biochem. J. 425, 137–148] that cytoprotection by the CyP inhibitor CsA (cyclosporin A) is improved by selective targeting to mitochondria. To investigate this further, we have developed an improved mtCsA (mitochondrial-targeted CsA) by modifying the spacer linking the CsA to the TPP+ (triphenylphosphonium) (mitochondrial-targeting) cation. The new mtCsA exhibits an 18-fold increase in binding affinity for CyP-D over the prototype and a 12-fold increase in potency of inhibition of the PT in isolated mitochondria, owing to a marked decrease in non-specific binding. The cytoprotective capacity was assessed in isolated rat cardiomyocytes subjected to transient glucose and oxygen deprivation (pseudo-I/R). The new mtCsA was maximally effective at lower concentrations than CsA (3–15 nM compared with 50–100 nM) and yielded improved cytoprotection for up to 3 h following the pseudo-ischaemic insult (near complete compared with 40%). These data indicate the potential value of selective CyP-D inhibition in cytoprotection
Highly saline fluid inclusions in Chamundi granite, South India
Fluid inclusions in minerals and rock represent a potentially valuable source of information about the composition and density of fluids present during the formation and evolution of rocks. Our preliminary studies on Chamundi granite have indicated presence of highly saline inclusions (up to 50-60 wt.% Nacl equivalent) as well as low-salinity inclusions (8 to 22 wt.% NaCl equivalent). Data on temperture of homogenization suggest that they represent remnant fluids of magmatic origin trapped in minerals
Velocity measurement in the hydrocyclone by oil droplet, doppler ultrasound velocimetry, and CFD modelling
International audienceTo develop the water treatment process, the hydrocyclone is now used as a unit to operate. Understanding hydrodynamics is a key step to improve the separation process efficiency. Recently, a new simple method called the oil droplet method was proposed by Bamrungsri et al. [Chem. Eng. Res. Design 86, 1263-1270 (2008)] and applied to velocity measurements in a hydrocyclone. The Doppler Velocimetry measurements and computational fluid dynamics (CFD) have been proposed by many researchers as effective for studying the flow field of a hydrocyclone. This work presents a comparison of the experimental results from these two methods along with those obtained from numerical simulations. The numerical calculations of the 3D flow field were performed with FLUENT using the k-epsilon model and the Reynolds stress model (RSM). Measurements and CFD simulations were performed for two hydrocyclone configurations (5 and 10cm diameter). Doppler ultrasound velocimetry data and CFD-RSM results are in close agreement. The oil droplet method is less accurate for the continuous phase velocity profiles but is promising for the validation of Lagrangian tracking simulations
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