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1.
Sensors (Basel) ; 24(15)2024 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-39123845

RESUMEN

For industry image data, this paper proposes an image classification method based on stochastic configuration networks and multi-scale feature extraction. The multi-scale features are extracted from images of different scales using deep 2DSCN, and the hidden features of multiple layers are also connected together to obtain more informational features. The integrated features are fed into SCNs to learn a classifier which improves the recognition rate for different categories. In the experiments, a handwritten digit database and an industry hot-rolled steel strip database are used, and the comparison results demonstrate the proposed method can effectively improve the classification accuracy.

2.
ACS Omega ; 8(29): 26458-26478, 2023 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-37521622

RESUMEN

The Chamdo Basin is a secondary basin in the eastern part of Tibet China and is one of the most promising of petroliferous basins for new petroleum exploration. The Qamdo Basin records a complex burial history from the Mesozoic to the Cenozoic; however, the poorly constrained sedimentology of Cenozoic strata in this basin has severely obscured the overall profile and impeded further explorations of oil and gas resources. Here, we conduct whole-rock geochemical analyses of major, trace, and rare earth elements in fine-grained clastic rocks of the Paleocene Gongjue Formation, Qamdo Basin to reveal depositional environments, provenance, and tectonic setting. Petrologically, the Gongjue Formation is dominated by red fine-grained sandy mudstones/siltstones with ripple marks. The high values of the chemical index of alteration (avg. of 78.93), chemical index of weathering (avg. of 90.10), and index of compositional variability (avg. of 2.5) suggest that the basin has undergone heavy weathering. Cross-plots of La vs Th, Th vs Sc vs Zr/10, and Th vs Co vs Zr/10 reveal a continental arc tectonic setting. Paleosalinity (Sr/Ba), paleoclimate (Sr/Cu), and redox proxies (V/Cr, U/Th, and enrichment factors of Mo and U) indicate brackish to saline and oxidizing paleowater masses during deposition of the Gongjue Formation. Provenance analyses via elements and petrology reveal that sediments in the Gongjue Formation are mainly derived from intermediate-acidic rocks of the upper crust. We conclude that the first and third members are more arid climate and heavily chemically weathered than the second member. In combination with previous studies of the structural evolution of the Qamdo Basin since the Paleogene, a model is built to describe the sedimentary environment and evolution of the Qamdo Basin during transition to the Paleocene. The first and third members, i.e., the Eg1 and Eg3 members of the Gongjue Formation, are dominated by an oxidizing environment of seawater-saltwater, and the climate ranges from warm and humid to arid and hot, with relatively stable environmental changes. The Eg2 member of the Gongjue Formation is dominated by an oxidizing environment of seawater-saltwater, and the climate ranges from warm and humid to arid and hot, with more frequent environmental evolution. Our model aids in better understanding of the Paleocene climate evolution of the eastern Tibetan Plateau.

3.
Heliyon ; 9(2): e13173, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36785828

RESUMEN

The Youganwo Formation oil shale located in the Maoming Basin represents a large commercially valuable lacustrine oil shale resource and a potential bio-shale gas reservoir in South China. With the aim of deepening the understanding of factors that influence organic matter enrichment, this research conducted a geochemical investigation to reconstruct the depositional paleoenvironment of bioproductivity, preservation and dilution. Youganwo Formation oil shale is mainly deposited in semi-deep to deep-lake environments with relatively warm and humid paleoclimate in the subtropical-temperate zone. The total organic carbon (TOC) content (1.46-11.85%), S2 values (4.79-115.80 mg HC/mg rock) and HI (328-1040 mg HC/mg TOC) indicate that the oil shale has a good oil source rock potential. TOC content, (S1 + S2) values and vitrinite reflectance values show that its marginally mature organic matter (OM) belongs to kerogen type I-III with good oil-generating potential. A 3rd order sequence was identified in the Yougnwo formation. Subsequently, the multiple factors including bioproductivity, preservation and dilution that control the OM enrichment of oil shale within system tracts were discussed. Moderate-quality oil shales (Oy-1) were developed in the transgressive systems tract (TST) in an oxidizing condition with abundant detrital input. High-quality oil shales (Oy-2) were deposited during the high-stand systems tract (HST) with increased accommodation space, improved preservation conditions, warm and humid climate, higher water bioproductivity and minimum detrital matter input. During the regressive systems tract (RST, Oy-3), higher detrital matter input and fresher water led to lower TOC values. Among these multiple factors, dilution condition was the major one that influences OM abundance and variation on the basis of sufficient organic matter input. Thus, OM enrichment models of Oy-1, Oy-2 and Oy-3 sub-members were established. The OM enrichment and quality in oil shale were controlled by the combined effect of bioproductivity, preservation, and dilution.

4.
Nucl Med Commun ; 29(5): 462-4, 2008 May.
Artículo en Inglés | MEDLINE | ID: mdl-18391731

RESUMEN

OBJECTIVE: To evaluate the radiation field feature of Re esophageal stent and provide scientific basis for clinical application. METHODS: We measure the beta-ray, gamma-ray and bremssfrahlung dose of every selected point on the bionics esophageal stent and then draw out computer software by mathematical formula. RESULTS: The radiation field of Re esophageal stent has its own feature: the max range of beta-ray is 11 mm, 90% dose construction field is within 1.5 mm, 95% dose range is within 2.5 mm, and only 4.21% of total energy of gamma-ray and bremssfrahlung is out of 6.5 mm range. The absorption dose of every direction in same point of the esophageal model was similar (P>0.05). CONCLUSION: Beta ray is the major radiation of Re esophageal stent while gamma-ray and bremssfrahlung are 4.21% among the radiation field. The max dose construction field is within 0.5-1.5 mm, just short at the depth of esophagus mucosa within 0.5-1.5 mm range. So Re stent is a good choice of palliative intracavitary radiotherapy of esophageal carcinoma.


Asunto(s)
Braquiterapia/instrumentación , Esófago/cirugía , Radiometría/métodos , Dosificación Radioterapéutica , Stents , Diseño de Equipo , Análisis de Falla de Equipo
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