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Methodology and Equations of Mineral Production Forecast
—Part I. Crude Oil in the UK and Gold in Nevada, USA. Prediction of Late Stages of Production
 [PDF]

Sergio Pérez Rodríguez
Open Journal of Geology (OJG) , 2013, DOI: 10.4236/ojg.2013.35040
Abstract:

The equations of mineral production forecast link the change in time of mineral reserves with the production and the ratio of reserves to production. These equations allow us to model the development of the mineral resources evaluated at any scale. Probabilistic bidimensional charts made from montecarlo simulations provide intervals of confidence for the forecasts. The set of equations is devised and presented for a variety of applications to the oil and gas industry, as well to the production of any other mineral resource, either metals or non metals, whose ore deposit volumes and production might be quantified. The cases studied in the UK and USA are at late stages of production, periods for what the equations are most suitable to be applied without further adjustments. Experimental design allows the diagnosis of the likely values of the variables pertaining to the equations, in order to achieve the results provided by conventional production forecasts or to explore other scenarios of investigation. The method can be practical to evaluate commitments of production of mineral resources with time, to support strategic plans for companies, corporations, countries or regions based on those evaluations, for the screening and ranking of mineral assets based on their production potential and many other tasks where the prediction of future volumes of mineral production is required.

Methodology and Equations of Mineral Production Forecast. Part II. The Fundamental Equation. Crude Oil Production in USA  [PDF]
Sergio Pérez Rodríguez
Open Journal of Geology (OJG) , 2013, DOI: 10.4236/ojg.2013.36044
Abstract:

The fundamental equation of mineral production allows to model and design the dynamics of mineral production, however complex they are or could be. It considers not only the case of a constant production to reserves ratio for given intervals of time, but with a piecewise approach, it is also enabled to account the variation on time of this ratio. With a constant production to reserves ratio, the limit expression of the fundamental equation takes the form of an Erlang distribution with a fixed shape parameter. The rate parameter equals the scale factor. The discrete piecewise version, instead of considering the reserves and the production to reserves ratio being constant through certain intervals of time, updates both variables by units of time. This version, using either lineal or non lineal functions for the variables involved, let to model known production profiles or to forecast them by experimental design. The Hubbert’s linearization updated with recent data and the p-box method applied to determine ultimate recovery of U.S. crude oil reserves indicate official accounts underestimate them. The analysis of the ideal model of production based on Hubbert’s linearization and curve, can be made by decomposing it in the distribution with time of the reserves and of the production to reserves ratio. The distribution of reserves with time is synchronized for both the ideal Hubbert’s curve and real profiles, disregarding whether they match or not. The departure of real profiles from the ideal Hubbert’s curve lies on the differences or correspondences of the distribution with time of the production to reserves ratio. The MonteCarlo simulation applied to forecast US crude oil production for the next five years points to a slow decline, with average annual yields presenting a difference lower than 10% between the start and the end of the simulation.

Optimization of biomass, total carotenoids and astaxanthin production in Haematococcus pluvialis Flotow strain Steptoe (Nevada, USA) under laboratory conditions
CIFUENTES,ANA S; GONZáLEZ,MARIELA A; VARGAS,SILVIA; HOENEISEN,MARITZA; GONZáLEZ,NELSON;
Biological Research , 2003, DOI: 10.4067/S0716-97602003000300006
Abstract: the microalga haematococcus pluvialis flotow is one of the natural sources of astaxanthin, a pigment widely used in salmon feed. this study was made to discover optimal conditions for biomass and astaxanthin production in h. pluvialis from steptoe, nevada (usa), cultured in batch mode. growth was carried out under autotrophic (with nano3, nh4cl and urea) and mixotrophic conditions (with 4, 8, 12 mm sodium acetate) under two photon flux densities (pfd) (35 and 85 μmol m-2 s-1). the carotenogenesis was induced by 1) addition of nacl (0.2 and 0.8 %), 2) n-deprivation and 3) high pfd (150 μmol m-2 s-1). total carotenoids were estimated by spectrophotometry and total astaxanthin by hplc. ammonium chloride was the best n-source for growth (k=0.7 div day-1, 228-258 mg l-1and 2.0 x 105 - 2.5 x 105 cells ml-1 at both pfd, respectively). with increasing acetate concentration, a slight increment in growth occurred only at 85 μmol m-2 s-1. light was the best inductive carotenogenic factor, and the highest carotenoid production (4.9 mg l-1, 25.0 pg cell-1) was obtained in cultures pre-grown in nitrate at low light. the nacl caused an increase in carotenoid content per cell at increasing salt concentrations, but resulted in a high cell mortality and did not produce any increment in carotenoid content per volume compared to cultures grown at 150 μmol m-2 s-1. the highest carotenoid content per cell (22 pg) and astaxanthin content per dry weight (10.3 mg g-1) (1% w/w) were obtained at 85 μmol m-2 s-1 with 0.8% nacl.
Optimization of biomass, total carotenoids and astaxanthin production in Haematococcus pluvialis Flotow strain Steptoe (Nevada, USA) under laboratory conditions
ANA S CIFUENTES,MARIELA A GONZáLEZ,SILVIA VARGAS,MARITZA HOENEISEN
Biological Research , 2003,
Abstract: The microalga Haematococcus pluvialis Flotow is one of the natural sources of astaxanthin, a pigment widely used in salmon feed. This study was made to discover optimal conditions for biomass and astaxanthin production in H. pluvialis from Steptoe, Nevada (USA), cultured in batch mode. Growth was carried out under autotrophic (with NaNO3, NH4Cl and urea) and mixotrophic conditions (with 4, 8, 12 mM sodium acetate) under two photon flux densities (PFD) (35 and 85 μmol m-2 s-1). The carotenogenesis was induced by 1) addition of NaCl (0.2 and 0.8 %), 2) N-deprivation and 3) high PFD (150 μmol m-2 s-1). Total carotenoids were estimated by spectrophotometry and total astaxanthin by HPLC. Ammonium chloride was the best N-source for growth (k=0.7 div day-1, 228-258 mg l-1and 2.0 x 10(5) - 2.5 x 10(5) cells ml-1 at both PFD, respectively). With increasing acetate concentration, a slight increment in growth occurred only at 85 μmol m-2 s-1. Light was the best inductive carotenogenic factor, and the highest carotenoid production (4.9 mg l-1, 25.0 pg cell-1) was obtained in cultures pre-grown in nitrate at low light. The NaCl caused an increase in carotenoid content per cell at increasing salt concentrations, but resulted in a high cell mortality and did not produce any increment in carotenoid content per volume compared to cultures grown at 150 μmol m-2 s-1. The highest carotenoid content per cell (22 pg) and astaxanthin content per dry weight (10.3 mg g-1) (1% w/w) were obtained at 85 μmol m-2 s-1 with 0.8% NaCl.
Ammonia at Blodgett Forest, Sierra Nevada, USA  [PDF]
M. L. Fischer and D. Littlejohn
Atmospheric Chemistry and Physics Discussions , 2007,
Abstract: Ammonia is a reactive trace gas that is emitted in large quantities by animal agriculture and other sources in California, which subsequently forms aerosol particulate matter, potentially affecting visibility, climate, and human health. We performed initial measurements of NH3 at the Blodgett Forest Research Station (BFRS) during a two week study in June, 2006. The site is used for ongoing air quality research and is a relatively low-background site in the foothills of the Sierra Nevada. Measured NH3 mixing ratios were quite low (<1 to ~2 ppb), contrasting with typical conditions in many parts of the Central Valley. Eddy covariance measurements showed NH3 fluxes that scaled with measured NH3 mixing ratio and calculated aerodynamic deposition velocity, suggesting dry deposition is a significant loss mechanism for atmospheric NH3 at BFRS. A simple model of NH3 transport to the site supports the hypothesis that NH3 is transported from the Valley to BFRS, but deposits on vegetation during the summer. Further work is necessary to determine whether the results obtained in this study can be generalized to other seasons.
Forecasting future oil production in Norway and the UK: a general improved methodology  [PDF]
Lucas Fievet,Zalàn Forrò,Peter Cauwels,Didier Sornette
Quantitative Finance , 2014,
Abstract: We present a new Monte-Carlo methodology to forecast the crude oil production of Norway and the U.K. based on a two-step process, (i) the nonlinear extrapolation of the current/past performances of individual oil fields and (ii) a stochastic model of the frequency of future oil field discoveries. Compared with the standard methodology that tends to underestimate remaining oil reserves, our method gives a better description of future oil production, as validated by our back-tests starting in 2008. Specifically, we predict remaining reserves extractable until 2030 to be 188 +/- 10 million barrels for Norway and 98 +/- 10 million barrels for the UK, which are respectively 45% and 66% above the predictions using the standard methodology.
Ordovician sponges from the Montgomery Limestone, Taylorsville area, northern Sierra Nevada, California, USA  [PDF]
Rigby J K,Potter A W,Anderson N K
Bulletin of Geosciences , 2008, DOI: 10.3140/bull.geosci.2008.03.299
Abstract: The modest faunule of silicified fossil demosponges, documented here, was recovered from the Upper Ordovician Montgomery Limestone in the Taylorsville area, in the northern Sierra Nevada of northern California. Included are specimens of the ceractinomorph angullongiid Amblysiphonelloidea tubulara Rigby & Potter, 1986, the girtyocoelliid Girtyocoeliana epiporata (Rigby & Potter, 1986), the sebargasiid Amblysiphonella sp., and the cliefdenellids Cliefdenella alaskaensis Stock, 1981, and Rigbyetia obconica (Rigby & Potter, 1986). In addition, specimens of the vaceletiid Corymbospongia adnata Rigby & Potter, 1986, are described and figured. The assemblage is closely related to faunules of sphinctozoan sponges earlier reported by Rigby & Potter (1986) from the eastern Klamath Mountains, to the west in northern California.
Surface motion of active rock glaciers in the Sierra Nevada, California, USA: inventory and a case study using InSAR  [PDF]
Lin Liu,C. I. Millar,R. D. Westfall,H. A. Zebker
The Cryosphere Discussions , 2013, DOI: 10.5194/tcd-7-343-2013
Abstract: Despite the abundance of rock glaciers in the Sierra Nevada of California, USA, few efforts have been made to measure their surface flow. Here we use the interferometric synthetic aperture radar (InSAR) technique to compile a~benchmark inventory describing the kinematic state of 59 active rock glaciers in this region. Statistically, these rock glaciers moved at speeds range from 15 cm yr 1 to 88 cm yr 1 with a mean value of 55 cm yr 1 in the late summer of 2007. We also find a spatial gradient: rock glaciers in the southern Sierra Nevada moved faster than the ones in the central Sierra Nevada. In addition to the inventory mapping, we also conduct a case study to measure the surface flow of the Mount Gibbs rock glacier in fine spatial and temporal detail. The InSAR measurements over this target reveal (1) that the spatial pattern of surface flow is influenced by surface geomorphological features and (2) a significant seasonal variation of flow speed whose peak value was 48 cm yr 1 in the fall, more than twice the minimum value observed in the spring. The seasonal variation lagged air temperatures by three months and likely results from temporal changes in mechanical strength of mixing debris and ice, internal melting of ice, and surface snow cover. Our finding on the seasonal variation of surface speed reinforces the importance of a long time series with high temporal sampling rates to detect possible long-term changes of rock glaciers in a warming climate.
Abrupt changes in an 8000-year precipitation reconstruction for Nevada, the Western USA

GU Xiangqian,JIANG Jianmin,Franklin SCHWING,Roy MENDELSSOHN,

地理学报 , 2005,
Abstract: A scanning t-test algorithm for detecting multiple time-scale abrupt changes in the level of a time-series was used to analyze an 8000 year time series of annual precipitation which was reconstructed from tree rings for the Nevada Climate Division 3 in the western USA. The tree ring samples were gathered from eight states in the southwestern USA. Twenty-two change-points were identified by the algorithm and these were used to partition the tree-ring series into twenty-three relatively Wet/Normal/Dry episodes. These twenty-three episodes were collaborated by a coherency analysis of abrupt changes between the precipitation reconstruction series and the TIC/δ18O records from cored sediments of Pyramid Lake in Nevada, and by comparison with published results from related studies. These episodes were also compared with studies of the global climate change and with records of climate change in China during the same periods. The results suggest that the precipitation reconstruction series is quite valuable for climate-change research on multi-centurial time-scales in the western USA, and that the scanning t-test and coherency detection algorithms may have a wide use for detecting multiple time-scale abrupt changes in a long time series.As the TIC and δ18O record series are high resolution with unequal sampling intervals ranging between 3 and 14 years, a new algorithm was developed to deal with the unequal time intervals in the series.
Forecast of Maize Production in Henan Province  [PDF]
Bingjun Li, Xiaoxiao Zhu
American Journal of Plant Sciences (AJPS) , 2018, DOI: 10.4236/ajps.2018.911164
Abstract: Considering the influence of meteorological factors on maize production, in order to improve the yield of maize in Henan Province, a grey combination model is constructed to predict the yield of maize in Henan Province. Firstly, the yield of maize in 2017 is obtained by GM (1, 1) model; secondly, the trend yield of maize is obtained by HP filter method, then the meteorological yield of maize is obtained, and the yield of maize reduction is determined according to the meteorological yield. Combined with Markov model, the maize yield reduction in various cities in Henan Province is forecasted. Finally, based on the reduction of production, policy recommendations are made for maize production in Henan Province.
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