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California Carbon Offsets and Working Forest Conservation Easements
California’s cap-and-trade system is a vital laboratory for testing the effectiveness of this market-driven approach in meeting greenhouse gas emission reduction goals and the use of forestry-based carbon offsets within these systems generally. Based on this experience, this Article explores one of the primary challenges, layering offsets with working forest conservation easements, which currently limits opportunities to effectively use these tools in concert. Ultimately, this market may need to foster and rely on natural linkages with working forest conservation easements to develop these offsets and to better ensure that the critical societal objectives of these projects are being met
Production Costing Simulation in Thermal Power Systems Using the Mixture of Conditional Load Distribution Functions
In the 1980's the cumulant method became popular in reliability type algorithms for production cost evaluation, particularly in the evaluation of loss-of-load probability (LOLP), energy not served (ENS) and expected energy generation (EEG) of a set of generating units belonging to an electric power system. We developed a probabilistic model which is able to handle the uncertainty of both generating units and peak load forecast. In order to model the load including peak load forecast uncertainty we use conditional probability distributions. We show that the cumulant method is still applicable, as we can compute all the moments of the load duration curve (load distribution) without discretizing the density function of peak load forecast
Use of computer-aided analysis techniques for cover type mapping in areas of mountainous terrain
There are no author-identified significant results in this report
absO2luteU-Net: Tissue Oxygenation Calculation Using Photoacoustic Imaging and Convolutional Neural Networks
Photoacoustic (PA) imaging uses incident light to generate ultrasound signals within tissues. Using PA imaging to accurately measure hemoglobin concentration and calculate oxygenation (sO2) requires prior tissue knowledge and costly computational methods. However, this thesis shows that machine learning algorithms can accurately and quickly estimate sO2. absO2luteU-Net, a convolutional neural network, was trained on Monte Carlo simulated multispectral PA data and predicted sO2 with higher accuracy compared to simple linear unmixing, suggesting machine learning can solve the fluence estimation problem. This project was funded by the Kaminsky Family Fund and the Neukom Institute
Multiple resource evaluation of region 2 US forest service lands utilizing LANDSAT MSS data
The author has identified the following significant results. LANDSAT MSS imagery provided an excellent overview which put a geomorphic study into a regional perspective, using scale 1:250,000 or smaller. It was used for deriving a data base for land use planning for southern San Juan Mountains. Stereo pairing of adjacent images was the best method for all geomorphic mapping. Combining this with snow enhancement, seasonal enhancement, and reversal aided in interpretation of geomorphic features. Drainage patterns were mapped in much greater detail from LANDSAT than from a two deg quadrangle base
Analysis of multiple incidence angle SIR-B data for determining forest stand characteristics
For the first time in the U.S. space program, digital synthetic aperture radar (SR) data were obtained from different incidence angles during Space Shuttle Mission 41-G. Shuttle Imaging Radar-B (SIR-B) data were obtained at incidence angles of 58 deg., 45 deg., and 28 deg., on October 9, 10, and 11, 1984, respectively, for a predominantly forested study area in northern Florida. Cloud-free LANDSAT Thematic Mapper (T.M.) data were obtained over the same area on October 12. The SIR-B data were processed and then digitally registered to the LANDSAT T.M. data by scientists at the Jet Propulsion Laboratory. This is the only known digitally registered SIR-B and T.M. data set for which the data were obtained nearly simultaneously. The data analysis of this information is discussed
Chemical transformations in organic aerosol from biomass burning
International audienceFine aerosol particles were collected separately during daytime and nighttime at a tropical pasture site in Rondônia, Brazil, during the burning and dry-to-wet transition period in 2002. Total carbon (TC) and water-soluble organic carbon (WSOC) were measured by evolved gas analysis (EGA). Based on the thermochemical properties of the fine aerosol, the relative amounts of the low and higher molecular weight compounds were estimated. It was found that the thermally refractory (possibly higher molecular weight) compounds dominated the TC composition. Their contribution to TC was higher in the daytime samples than in the nighttime ones. The relative share of WSOC also showed a statistically significant diel variation and so did its refractory fraction. Anhydrosugars and phenolic acids were determined by GC-MS and their diel variation was studied. Based on the decrease of their relative concentrations between the biomass burning and transition periods and their distinctly different diel variations, we suggest that the phenolic acids may undergo chemical transformations in the aerosol phase, possibly towards more refractory compounds (humic-like substances, HULIS), as has been suggested previously. These conclusions are supported by the results of the thermally assisted hydrolysis and methylation gas chromatography-mass spectrometry of the same filter samples
Stratification of single-vessel coronary stenosis by ischemic threshold at the onset of wall motion abnormality during continuous monitoring of left ventricular function by semisupine exercise echocardiography.
peer reviewedWe studied the relation between the ischemic threshold at the onset of wall motion abnormality on exercise echocardiography (EE) and the severity of coronary stenosis in patients with 1-vessel coronary artery disease (CAD). We screened 216 consecutive patients who underwent coronary angiography and EE for suspected CAD. Ninety-five (74 men; age, 56 +/- 12 years) satisfied the study criteria, that is, the presence of 1-vessel disease or no evidence of CAD on angiography and a normal baseline echocardiogram. Eighty-seven patients had 1-vessel CAD on angiography, and exercise-induced wall motion abnormality occurred in 73 (77%). Optimal cutoff values of percent diameter stenosis and minimal lumen diameter for predicting a positive EE were 61% (sensitivity and specificity of 76%) and 1.12 mm (sensitivity and specificity of 74%). Among patients with positive EE, heart rate-blood pressure product at ischemic threshold was correlated with quantitative coronary stenosis (r = -0.72, P <.001). The ischemic threshold from continuous monitoring of left ventricular function during semisupine EE is correlated with the severity of coronary stenosis among patients with 1-vessel disease and a normal resting echocardiogram
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