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81.
Leite da Silva A.M. Da Fonseca Manso L.A. De Oliveira Mello J.C. Billinton R. 《Power Systems, IEEE Transactions on》2000,15(1):73-80
This paper presents a new methodology to evaluate loss of load indices, with particular emphasis on LOLC (loss of load cost) assessment, for composite generation and transmission systems considering time varying loads for different areas or buses. The proposed approach, named pseudo-chronological simulation, retains the computational efficiency of nonsequential Monte Carlo simulation and the ability to model chronological load curves in sequential simulation. It considers the actual blocks of unsupplied energy per consumer class, per bus, and the respective duration, to accurately characterize the interruption process. Case studies on the IEEE-MRTS (Modified Reliability Test System) and the BSS (Brazilian South-Southeastern System) are presented and discussed 相似文献
82.
K.M.A. Dias da Cunha S.M.M. Carvalho C.V. Barros Leite G.B. Baptista A.S. Paschoa 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》1989,280(2-3):492-494
A six-stage cascade impactor was used to collect airborne dust particulates in the grinding area of a monazite separation plant. The samples were analysed using particle-induced X-ray emission (PIXE) to determine the elemental concentrations, with special attention to thorium and uranium concentrations. The particle size distribution of the samples containing thorium and uranium were determined. The mass median aerodynamic diameter (MMAD) obtained was 1.15 μm for both elements. The activity median aerodynamic diameter (AMAD) was estimated based on the MMAD. The results are compared with ICRP recommendations for derived air concentrations (DAC) for thorium and uranium in restricted areas. 相似文献
83.
M. Anicete-Santos R. C. Lima E. Orhan M. A. M. A. Maurera L. G. P. Simões G. Souza P. S. PIZANI E. R. Leite J. A. Varela E. Longo 《Scientific Modeling and Simulation》2005,12(2-3):111-119
The SrWO4 (SWO) powders were synthesized by the polymeric precursor method and annealed at different temperatures. The SWO structure was obtained by X-ray diffraction and the corresponding photoluminescence (PL) spectra was measured. The PL results reveal that the structural order–disorder degree in the SWO lattice influences in the PL emission intensity. Only the structurally order–disordered samples present broad and intense PL band in the visible range. To understand the origin of this phenomenon, we performed quantum-mechanical calculations with crystalline and order–disordered SWO periodic models. Their electronic structures were analyzed in terms of band structure. The appearance of localized levels in the band gap of the order–disordered structure was evidenced and is a favorable condition for the intense PL to occur. 相似文献
84.
85.
Haemagglutination of purified F42 fimbriae was found to be inhibited by N-acetyl-galactosamine. Purified F42 fimbrial adhesin reacted with distinct membrane components from chicken erythrocytes (35, 37 and 40 kDa) in immunoblot analysis, suggesting that the binding occurred to proteins or glycoproteins. 相似文献
86.
87.
Fabio L. Leite Alessandra Firmino Carlos E. Borato Luiz H.C. Mattoso Wilson T.L. da Silva Osvaldo N. Oliveira 《Synthetic Metals》2009,159(21-22):2333-2337
The interaction between poly(o-ethoxyaniline) (POEA) adsorbed onto solid substrates and humic substances (HS) and Cu2+ ions has been investigated using UV–vis spectroscopy and atomic force microscopy (AFM). Both HS and Cu2+ are able to dope POEA and change film morphology. This interaction was exploited in a sensor array made with nanostructured films of POEA, sulfonated lignin and HS, which could detect small concentrations of HS and Cu2+ in water. 相似文献
88.
BS Glatt DB Sarwer DE O'Hara C Hamori LP Bucky D LaRossa 《Canadian Metallurgical Quarterly》1999,103(1):76-82; discussion 83-5
Reduction mammaplasty is performed typically to alleviate the painful physical symptoms of macromastia. Women who suffer from macromastia also frequently present to the plastic surgeon with heightened body image dissatisfaction and maladaptive behavioral changes in response to their breast size. Numerous investigations have demonstrated improvement in physical symptoms after breast reduction surgery. Studies have also suggested that psychological improvement occurs postoperatively; however, they have not used well-validated, standardized psychological measures. The present study is a retrospective analysis of the physical and psychological status of women who underwent reduction mammaplasty. One hundred ten patients who underwent a reduction mammaplasty between 1982 and 1996 were mailed a packet of questionnaires designed to assess current physical symptoms and body image. Sixty-one of the 110 patients (55 percent) responded. The vast majority reported substantial improvement or elimination of neck, back, shoulder, and breast pain, grooving from bra straps, poor posture, skin irritation, and social embarrassment. In addition, they reported significantly less dissatisfaction with their breasts as compared with a sample of breast reduction patients assessed preoperatively. Symptom relief and improved body image occurred independently of preoperative body weight, as we found few significant differences between obese and non-obese women concerning the resolution of physical symptoms or improvement in body image. Results provide further evidence of the efficacy of reduction mammaplasty not only for relief of physical symptoms but also for alleviation of body image dissatisfaction. 相似文献
89.
Quantum states engineering: Recurrence formula including states with even and odd numbers of photons
Abstract A previous recurrence formula using the resonant atom-field interaction for the generation of a field state in a cavity is extended to arbitrary states having even and odd numbers of photons in their photon-number distribution. 相似文献
90.
Claudia Pessoa Dr. Paulo Michel P. Ferreira Letícia Veras C. Lotufo Dr. Manoel O. de Moraes Prof. Suellen M. T. Cavalcanti Lucas Cunha D. Coêlho Marcelo Z. Hernandes Dr. Ana Cristina L. Leite Prof. Carlos A. De Simone Dr. Vlaudia M. A. Costa Dr. Valdênia M. O. Souza Dr. 《ChemMedChem》2010,5(4):523-528