778 research outputs found

    Assessing the representativeness of wind data for wind turbine site evaluation

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    Once potential wind turbine sites (either for single installations or clusters) are identified through siting procedures, actual evaluation of the sites must commence. This evaluation is needed to obtain estimates of wind turbine performance and to identify hazards to the machine from the turbulence component of the atmosphere. These estimates allow for more detailed project planning and for preliminary financing arrangements to be secured. The site evaluation process can occur in two stages: (1) utilizing existing nearby data, and (2) establishing and monitoring an onsite measurement program. Since step (2) requires a period of at least 1 yr or more from the time a potential site has been identified, step (1) is often an essential stage in the preliminary evaluation process. Both the methods that have been developed and the unknowns that still exist in assessing the representativeness of available data to a nearby wind turbine site are discussed. How the assessment of the representativeness of available data can be used to develop a more effective onsite meteorological measurement program is also discussed

    Doppler lidar results from the San Gorgonio Pass experiments

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    During FY-84, the Doppler Lidar data from the San Gorgonio Pass experiments were analyzed, evaluated, and interpreted with regard to signal strength, signal width, magnitude and direction of velocity component and a goodness parameter associated with the expected noise level of the signal. From these parameters, a screening criteria was developed to eliminate questionable data. For the most part analysis supports the validity of Doppler Lidar data obtained at San Gorgonio Pass with respect to the mean velocity magnitude and direction. The question as to whether the Doppler width could be interpreted as a measure of the variance of the turbulence within the Doppler Lidar System (DLS) focal volume was not resolved. The stochastic nature of the Doppler broadening from finite residence time of the particles in the beam as well as other Doppler broadening phenomenon tend to mask the Doppler spread associated with small scale turbulence. Future tests with longer pulses may assist in better understanding

    Analysis of the NASA/MSFC Airborne Doppler Lidar results from San Gorgonio Pass, California

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    Two days during July of 1981 the NASA/MSFC Airborne Doppler Lidar System (ADLS) was flown aboard the NASA/AMES Convair 990 on the east side of San Gorgonio Pass California, near Palm Springs, to measure and investigate the accelerated atmospheric wind field discharging from the pass. The vertical and horizontal extent of the fast moving atmospheric flow discharging from the San Gorgonio Pass were examined. Conventional ground measurements were also taken during the tests to assist in validating the ADLS results. This particular region is recognized as a high wind resource region and, as such, a knowledge of the horizontal and vertical extent of this flow was of interest for wind energy applications. The statistics of the atmospheric flow field itself as it discharges from the pass and then spreads out over the desert were also of scientific interests. This data provided the first spatial data for ensemble averaging of spatial correlations to compute longitudinal and lateral integral length scales in the longitudinal and lateral directions for both components

    Analysis of the NASA/MSFC airborne Doppler lidar results from San Gorgonio Pass, California

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    The NASA/MSFC Airborne Doppler Lidar System was flown in July 1981 aboard the NASA/Ames Convair 990 on the east side of San Gorgonio Pass California, near Palm Springs, to measure and investigate the accelerated atmospheric wind field discharging from the pass. At this region, the maritime layer from the west coast accelerates through the pass and spreads out over the valley floor on the east side of the pass. The experiment was selected in order to study accelerated flow in and at the exit of the canyon. Ground truth wind data taken concurrently with the flight data were available from approximately 12 meteorological towers and 3 tala kites for limited comparison purposes. The experiment provided the first spatial data for ensemble averaging of spatial correlations to compute lateral and longitudinal length scales in the lateral and longitudinal directions for both components, and information on atmospheric flow in this region of interest from wind energy resource considerations

    Avicennia germinans (L.) Stearn

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    https://thekeep.eiu.edu/herbarium_specimens_byname/18928/thumbnail.jp

    A Logic of Blockchain Updates

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    Blockchains are distributed data structures that are used to achieve consensus in systems for cryptocurrencies (like Bitcoin) or smart contracts (like Ethereum). Although blockchains gained a lot of popularity recently, there is no logic-based model for blockchains available. We introduce BCL, a dynamic logic to reason about blockchain updates, and show that BCL is sound and complete with respect to a simple blockchain model

    Overview of the Quality and Completeness of Resource Assessment Data for the APEC Region

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    The availability of information and data on the renewable energy resources (solar, wind, biomass, geothermal, and hydro) for renewable energy technologies is a critical element in the successful implementation of these technologies. This paper presents a comprehensive summary of published information on these resources for each of 1 8 Asia-Pacific Economic Cooperation (APEC) economies. In the introductory sections, a discussion of the quality and completeness of this information is presented, along with recommendations on steps that need to be taken to facilitate the further development and deployment of renewable energy technologies throughout the APEC region. These sections are then followed by economy-specific reviews, and a complete bibliography and summary description for each citation. The major results of this survey are that a basis for understanding renewable energy resources is currently available for essentially all the economies, although there is a significant need to apply improved and updated resource assessment techniques in most. For example, most wind resource assessments rely on data collected at national weather stations, which often results in underestimates of the true potential wind resource within an economy. As a second example, solar resource assessments in most economies rely on an analysis of very simple sunshine record data, which results in large uncertainties in accurately quantifying the resource. National surveys of biomass, geothermal, and hydro resources are often lacking; in most cases, resources for these technologies were discussed for site-specific studies only. Thus, the major recommendations in this paper are to: ( 1 ) upgrade current or install new wind and solar measurement systems at key 'benchmark' locations to provide accurate, representative information on these resources; (2) apply advanced wind and solar resource assessment tools that rely on data quality assessment procedures, the use of satellite data, and models, and that can reliably interpolate the data collected at the benchmark sites; (3) conduct national surveys of biomass, geothermal, and hydro resources uniformly and consistently; and ( 4) establish a centralized data center that provides ready access to the most up-to-date and validated renewable resource data in all APEC economies

    Pancreatite em adulto com leucemia linfoblástica aguda usando L-asparaginase e sinvastatina: relato de caso e revisão sistemática

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    Context: Acute pancreatitis is a inflammatory process of the pancreas. It can be caused by gallstones, metabolic disorders, associated or not with alcohol abuse, or medication. Case Report: A 38-year-old man was admitted to the hospital because of worsening of nausea, abdominal pain, dizziness and white stool. Patient was diagnosed with severe acute pancreatitis. After six days of hospitalization, patient progressed into hypotension and severe bradycardia, and died. The patient used simvastatin chronically, and was in treat with L-asparaginase, both drugs related to the occurence of acute pancreatitis separately. Naranjo´s probability scale of adverse drug reaction established the causality between these medications and acute pancreatitis as probable. However, due to the absence of reports of causality, the acute pancreatitis is associated with to the use of L-asparaginase with possible drug interactions with simvastatin. Conclusion: It is very important to monitor patients treated with L-asparaginase, through careful observation of clinical signs and laboratory follow-up, as well as verification of other medications in use. The AP may have different levels of severity, being indispensable the quick diagnosis and early treatmentContexto: Pancreatite aguda é um processo inflamatório do pâncreas. É causada por cálculos biliares, desordens metabólicas, associadas ou não ao uso abusivo de álcool, ou medicamentos. Relato do Caso: Homem de 38 anos foi admitido no hospital em razão do agravamento de náuseas, dor abdominal, tontura e fezes brancas. O paciente foi diagnosticado com pancreatite aguda. Após seis dias de internação, paciente progrediu com hipotensão e bradicardia severa, evoluindo à óbito. O paciente fazia uso crônico de sinvastatina, e estava em tratamento com L-asparaginase, ambos fármacos, de modo separado, são relacionados com a ocorrência de pancreatite aguda severa. O algoritmo de Naranjo para estabelecimento de reação adversa a medicação classificou a causalidade entre as medicações citadas e a pancreatite aguda como provável. Porém, em razão da ausência relatos dessa causalidade, associa-se a pancreatite aguda ao uso de L-asparaginase, com possível interação medicamentosa com sinvastatina. Conclusão: É de suma importância o acompanhamento clínico e laboratorial de pacientes em uso de Lasparaginase para sinais de pancreatite aguda, sendo imprescindível o rápido diagnóstico e tratamento precoc

    40Ar/39Ar ages for deep (~3.3 km) samples from the Hawaii Scientific Drilling Project, Mauna Kea volcano, Hawaii

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    The Hawaii Scientific Drilling Project recovered core from a 3.5 km deep hole from the flank of MaunaKea volcano, providing a long, essentially continuous record of the volcano’s physical and petrologicdevelopment that has been used to infer the chemical and physical characteristics of the Hawaiian mantle plume. Determining a precise accumulation rate via 40Ar/39Ar dating of the shield-stage tholeiites, which constitute 95–98% of the volcano’s volume is challenging. We applied 40Ar/39Ar dating using laser- and furnace-heating in two laboratories (Berkeley and Curtin) to samples of two lava flows from deep in the core (~3.3 km). All determinations yield concordant isochron ages, ranging from 612 +/- 159 to 871 +/- 302 ka (2delta; with P = 0.90). The combined data yield an age of 681 +/- 120 ka (P = 0.77) for pillow lavas near the bottom of the core. This new age, when regressed with 40Ar/39Ar isochron ages previously obtained for tholeiites higher in the core, defines a constant accumulation rate of 8.4 +/- 2.6 m/ka that can be used to interpolate the ages of the tholeiites in the HSDP core with a mean uncertainty of about 83 ka. For example at ~3300 mbsl, the age of 664 +/- 83 ka estimated from the regression diverges at the 95% confidence level from the age of 550 ka obtained from the numerical model of DePaolo and Stolper (1996). The new data have implications for the timescale of the growth of Hawaiian volcanoes, the paleomagnetic record in the core, and the dynamics of the Hawaiian mantle plume
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