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641.
Assessment and propagation of uncertainties in input terms through an ocean-color-based model of primary productivity 总被引:1,自引:0,他引:1
Net primary productivity (NPP) fields, derived from satellite observations of ocean color, are commonly published without relevant information on uncertainties. In this study, we assessed the uncertainty in NPP estimates of the Vertically Generalized Productivity Model using a Monte Carlo approach. We did not consider the uncertainty stemming from the basic model formulation, but restricted the uncertainty analysis to input terms, which were generated by, or related to, remote sensing. The study was based on global monthly remote sensing data from 2005. We found that the typical distribution of uncertainty around the model output could be approximated by a lognormal probability density function. On average, NPP value in a grid cell was overestimated by 6%, relative to the mean of the corresponding uncertainty distribution. The random component of uncertainty in NPP, expressed as the coefficient of variation, amounted to an average of 108%. The systematic positive errors in individual grid cells built up to an overestimate of 2.5 Pg C in the annual global NPP of 46.1 Pg C. The largest individual contributor to the random uncertainty in NPP was the input term that describes the physiological state of phytoplankton. However, the biggest contribution to the systematic uncertainty in the model output came from the parameter that represents changes in the rate of chlorophyll-normalized photosynthesis with depth. Therefore, improvements in the accuracy of these two terms would have the largest potential to decrease the input-related uncertainty in the model NPP estimates. 相似文献
642.
Vorontsov MA Lachinova SL Beresnev LA Weyrauch T 《Journal of the Optical Society of America. A, Optics, image science, and vision》2010,27(11):A106-A121
Control methods and system architectures that can be used for locking in phase of multiple laser beams that are generated at the transmitter aperture plane of a coherent fiber-collimator array system (pupil-plane phase locking) are considered. In the proposed and analyzed phase-locking techniques, sensing of the piston phase differences is performed using interference of periphery (tail) sections of the laser beams prior to their clipping by the fiber-collimator transmitter apertures. This obscuration-free sensing technique eliminates the need for a beam splitter being directly located inside the optical train of the transmitted beams--one of the major drawbacks of large-aperture and/or high-power fiber-array systems. Numerical simulation results demonstrate efficiency of the proposed phase-locking methods. 相似文献
643.
The authors discuss the two basic forms of contractual arrangements leading to the development of the free market and describe the problems experienced during the contract phase employing the 'Montastan' system. 相似文献
644.
Anastasia K. Neklyudova Galina V. Portnova Anna B. Rebreikina Victoria Yu Voinova Svetlana G. Vorsanova Ivan Y. Iourov Olga V. Sysoeva 《International journal of molecular sciences》2021,22(4)
SHANK3 encodes a scaffold protein involved in postsynaptic receptor density in glutamatergic synapses, including those in the parvalbumin (PV)+ inhibitory neurons—the key players in the generation of sensory gamma oscillations, such as 40-Hz auditory steady-state response (ASSR). However, 40-Hz ASSR was not studied in relation to SHANK3 functioning. Here, we present a 15-year-old girl (SH01) with previously unreported duplication of the first seven exons of the SHANK3 gene (22q13.33). SH01’s electroencephalogram (EEG) during 40-Hz click trains of 500 ms duration binaurally presented with inter-trial intervals of 500–800 ms were compared with those from typically developing children (n = 32). SH01 was diagnosed with mild mental retardation and learning disabilities (F70.88), dysgraphia, dyslexia, and smaller vocabulary than typically developing (TD) peers. Her clinical phenotype resembled the phenotype of previously described patients with 22q13.33 microduplications (≈30 reported so far). SH01 had mild autistic symptoms but below the threshold for ASD diagnosis and microcephaly. No seizures or MRI abnormalities were reported. While SH01 had relatively preserved auditory event-related potential (ERP) with slightly attenuated P1, her 40-Hz ASSR was totally absent significantly deviating from TD’s ASSR. The absence of 40-Hz ASSR in patients with microduplication, which affected the SHANK3 gene, indicates deficient temporal resolution of the auditory system, which might underlie language problems and represent a neurophysiological biomarker of SHANK3 abnormalities. 相似文献
645.
646.
We have shown that in polyacetylene, for electric fields above 106 V/cm polarons are dissociated because the electron or hole can move much faster than the lattice distortion. Similar results should hold for poly(p-phenylene vinylene), PPV. To determine whether the free carriers thus created can be heated by the field sufficiently to allow impact ionization, we investigated free-carrier scattering in PPV. The important scatterers are longitudinal acoustic modes, molecular vibrations, and librational torsional modes. The coupling constants and important frequencies are known approximately for the first two of these processes in PPV. Using these values, some reasonable values for librons, and the calculated band structure of PPV, we conclude that at least some of the carriers could be heated to 2 eV at a field of ∼106 V/cm, and that they could acquire energy required for impact ionization at not much higher fields. 相似文献
647.
Svetlana Rodgers 《Journal of food science》2016,81(10):R2309-R2319
This paper offers a concise review of technical and operational concepts underpinning commercialization of minimally processed functional foods (FFs), foods with fresh‐like qualities commanding premium prices. The growing number of permitted nutritional content/health claims, many of which relate to well‐being, coupled with emerging extraction and food processing technologies offers new exciting opportunities for small and medium size enterprises (SMEs) specializing in fresh produce to play an active role in the health market. Supporting SMEs, governments could benefit from savings in healthcare costs and value creation in the economy. Consumers could benefit from novel FF formats such as refrigerated RTE (ready‐to‐eat) meals, a variety of fresh‐like meat‐, fish‐, and egg‐based products, fresh‐cut fruits and vegetables, cereal‐based fermented foods and beverages. To preserve these valuable commodities, mild biological (enzymatic treatment, fermentation and, bio‐preservation) and engineering solutions are needed. The latter include nonthermal techniques such as high‐pressure treatment, cook‐chill, sous‐vide, mirco‐encapsulation, vacuum impregnation and others. “De‐constructive” culinary techniques such as 3D food printing and molecular gastronomy as well as developments in nutrigenomics and digital technologies facilitate novel product formats, personalization and access to niche markets. In the operational sense, moving from nourishment to health improvement demands a shift from defensive market‐oriented to offensive market‐developing strategies including collaborative networks with research organizations. 相似文献
648.
The battery thermal management system based on phase change materials (PCMs) has proven to be a safe, inexpensive, and high-performance technology, which is currently gaining popularity over the other battery thermal management systems. PCMs are able to absorb heat generated by batteries, prolong battery life, and improve their performance. Organic compounds, such as paraffin, are widely used as phase change materials for the battery thermal management systems; however, there are no published data on the application of inorganic PCMs. Therefore, the main objective of this work is developing of two composite inorganic PCMs based on magnesium chloride hexahydrate and characterizing their properties for passive thermal control of lithium-ion battery packs. Moreover, to have a valid baseline and compare the behavior of two inorganic PCMs with currently commercialized and well investigated organic PCM, paraffin wax was used as reference material for both mixtures. All three PCMs were impregnated into the expanded graphite matrix to enhance their thermal conductivity. The material characterization studies, including thermal properties investigation, density and viscosity measurements, soaking and compression testing, evaluation of thermal expansion, thermal conductivity, and micro X-ray fluorescence analysis, were conducted for all PCMs. The results indicate that both inorganic mixtures are appropriate for thermal management of Li-ion battery packs. Future work with the developed and characterized composite inorganic PCMs will include electrical cycling studies and nail penetration tests to reveal their effectiveness for passive thermal management of Li-ion battery packs. 相似文献
649.
Nemanja Stanisavljević Živko Jovanović Tihomir Čupić Jovanka Lukić Jovanka Miljuš Đukić Svetlana Radović Aleksandar Mikić 《International Journal of Food Science & Technology》2013,48(10):2096-2104
Antioxidant activities were studied in methanolic and water extracts of nonprocessed, cooked and in vitro enzymatically digested seed flour, as well as in total protein hydrolysates and small peptide fractions (<3 and <10 kDa) of three pea and five grass pea cultivars. The antioxidative properties were determined by three spectrophotometric methods: 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) radical scavenging assay, Folin‐Ciocalteu (FC) reducing capacity assay and H2O2 scavenging. We also applied one luminometric assay for hydroxyl radical scavenging. The study showed that cooking and enzymatic digestion strongly enhanced the release of phenolic compounds in methanolic extracts of four analysed cultivars. Scavenging activity against DPPH radical, hydroxyl radical and hydrogen peroxide was increased in majority of analysed flour specimens subjected to processing. Our findings indicate that, besides the phenolic compounds, the small peptide fraction, especially the MW <3 kDa, in methanolic and aqueous extracts of cooked and digested seed flour significantly contribute to free radical and hydrogen peroxide scavenging activity in all investigated cultivars. Our data strongly suggest that simple cooking treatment and in vitro digestion of seed flour applied prior to extraction with methanol could improve antioxidative activity of obtained extracts. 相似文献
650.
This paper focuses on the optimization problem of a wind farm layout. This area of research is currently receiving widespread attention, as optimal positioning of the turbines promotes the financial viability of the wind farm and enhances the competitiveness of wind projects in the energy market. In this work, cuckoo search (CS), a modern population‐based metaheuristic optimization algorithm, is used. The objective is to find the turbine layout and types that maximize the net present value of the wind farm, while constraints on the turbine positions have to be met. The following constraints are considered: Firstly, the minimum distance between turbines for safe operation; secondly, a realistic wind farm shape including forbidden zones for installation and the existing infrastructure. Furthermore, the optimization of the wind farm includes an algorithm to find the least expensive layout of the wind farm roads and the electrical collector system. The algorithm is based on Dijkstra's shortest path and Prim's minimum spanning tree algorithms. The test results indicate that the infrastructure cost has a significant effect on the optimum wind farm solution. A genetic algorithm, commonly applied to wind farm micro‐siting problems, is used to benchmark the performance of the CS. The results show that the CS is capable of consistently finding better solutions than the genetic algorithm. 相似文献