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排序方式: 共有1322条查询结果,搜索用时 968 毫秒
1.
Paul-Baptiste Rubio François Louf Ludovic Chamoin 《International journal for numerical methods in engineering》2019,120(4):447-472
The motivation of this work is to address real-time sequential inference of parameters with a full Bayesian formulation. First, the proper generalized decomposition (PGD) is used to reduce the computational evaluation of the posterior density in the online phase. Second, Transport Map sampling is used to build a deterministic coupling between a reference measure and the posterior measure. The determination of the transport maps involves the solution of a minimization problem. As the PGD model is quasi-analytical and under a variable separation form, the use of gradient and Hessian information speeds up the minimization algorithm. Eventually, uncertainty quantification on outputs of interest of the model can be easily performed due to the global feature of the PGD solution over all coordinate domains. Numerical examples highlight the performance of the method. 相似文献
2.
Juana Maria de Lourdes Medina-Contreras Patrick Mailloux-Salinas Juventino III Colado-Velazquez Norma Leticia Gomez Viquez Gómez-Viquez Rodrigo Velázquez-Espejel Ana del Carmen Susunaga-Notario David Julian Arias-Chávez Guadalupe Bravo 《Journal of the science of food and agriculture》2020,100(7):3212-3219
3.
Systemic lupus erythematosus (SLE) is a multisystem organ disease, and involvement of the gastrointestinal system is relatively rare. We describe a 13-year-old girl who presented initially with abdominal pain, diarrhea, edema, and hypoalbuminemia. She was diagnosed with protein losing enteropathy (PLE) based on the significant increase of alpha 1-antitrypsin clearance in the stool. Two weeks after admission she developed clinical and serological findings that fulfilled the ACR criteria for SLE. Over 22 cases of lupus associated PLE have now been reported, but only 3 in children. Children with PLE should be evaluated for SLE. In addition, PLE should be suspected as a possible cause of unexplained edema and/or hypoalbuminemia in SLE. 相似文献
4.
The hydrolysis and condensation reactions of γ-APS have been studied in different acid content aqueous solution by using Fourier
Transform infrared (FT-IR) spectroscopy. The hydrolysis of γ-APS under the studied conditions can be followed by the increase
of the ethanol band located at 882 cm−1 and the decrease of the band due to the ρ(CH3) of γ-APS molecules located at 959 cm−1. Hydrolysis reaction is faster by increasing both H2O and acid concentrations, and it is completed when 3 moles of H2O per mole of γ-APS are used. The increase of the vibrational band located at 1146 cm−1 shows that condensation of the hydrolysed γ-APS molecules take place forming linear chains in poorly cross-linked structures.
Besides, both 8-membered cyclic siloxane formations and poorly cross-linked structures are formed and increase as the water
and acid content are increased. On the other hand, highly connected cross-linked structures do not appear due to the steric
hindrance of the non-hydrolysable aminopropyl group. The silanol band shows that hydrolysis is faster than condensation except
for samples with the lowest H2O content. 相似文献
5.
LA Pérula de Torres J Martínez de la Iglesia J Espejo Espejo MV Rubio Cuadrado I Enciso Berge FJ Fonseca del Pozo JM Aranda Lara 《Canadian Metallurgical Quarterly》1997,20(8):425-434
OBJECTIVE: To describe the health status of a population over 60 years and to study their relationship with several socio-demographic variables. DESIGN: A cross-sectional study, population based. SETTINGS: A community. PARTICIPANTS: A randomized sample of 1,103 non institutionalized people over 60 years living in the city of Cordoba (Spain). MEASUREMENTS AND MAIN RESULTS: By mean of a personal interview at home we used the OARS-MFAQ-VE questionnaire. Low self-rated health was associated with the age, to be female sex, a low cultural background, and a low income. Only 5.2% of the study people do not suffered any illness and 56% state that their health problems are major problems for doing their current activities. 4.9% declared to have some degree of physical incapacity. 3.7% of elderly population has an important cognitive deficit. CONCLUSIONS: The majority of elderly people has good health. Age is related with a poor health. Women have more health problems than men. 相似文献
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7.
Adiabatic switching is a technique to design low-power digital IC's. Fully adiabatic logics have expensive silicon area requirements. To solve this drawback, a quasi-adiabatic ternary logic is proposed. Its basis is presented, and to validate its performance, a 5×5 ternary digit multiplier is designed and implemented in a 0.7-μm CMOS technology. Results show a satisfactory power saving with respect to conventional and other quasi-adiabatic binary multipliers, and a decrease of the area needed with respect to a fully adiabatic binary one 相似文献
8.
Peter Eaton Andrea Ragusa Caroline Clavel Cristina T Rojas Paul Graham Raúl V Durán Soledad Penadés 《IEEE transactions on nanobioscience》2007,6(4):309-318
Glyconanoparticles which present carbohydrate and amino groups motifs at their surface were produced. These particles were highly stable and soluble in aqueous solutions. The presence of the carbohydrate groups also allowed the inclusion of more strongly binding groups, without affecting solubility. The binding of a model DNA, plasmid by these nanoparticles was studied by atomic force microscopy, transmission electron microscopy, and gel electrophoresis. Significant differences between the nanoparticles based on their affinities for the DNA were found, with implications for their potential use as nonviral gene delivery agents. 相似文献
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