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排序方式: 共有261条查询结果,搜索用时 78 毫秒
51.
In this article two linear problems with random Gaussian loading are transformed into multi-objective optimization problems. The first problem is the design of a pillar geometry with respect to a compressive random load process. The second problem is the design of a truss structure with respect to a vertical random load process for several frequency bands. A new algorithm, motivated by the Pincus representation formula hybridized with the Nelder–Mead algorithm, is proposed to solve the two multi-objective optimization problems. To generate the Pareto curve, the normal boundary intersection method is used to produce a series of constrained single-objective optimizations. The second problem, depending on the frequency band of excitation, can have as Pareto curve a single point, a standard Pareto curve, or a discontinuous Pareto curve, a fact that has been reported here for the first time in the literature, to the best of the authors’ knowledge. 相似文献
52.
Moreto Jéferson Aparecido Silva Pedro Henrique Sampaio de Moraes Moura Gabriel da Silva Camila Cristina Ferreira Deusmaque Carneiro da Cunha Thiago Henrique R. Silva Glaura Goulart Rouxinol Francisco de Siervo Abner Gelamo Rogério Valentim 《Journal of Materials Science》2022,57(19):8779-8799
Journal of Materials Science - Flexible self-standing supercapacitor devices (FSSS) have attracted great attention in several areas due to their potential use in a wide range of applications, such... 相似文献
53.
Most patients who present with a large solid renal mass and evidence of advanced malignancy will have primary renal cell carcinoma but a small subset with similar features have different and more treatable malignancies. We identified 7 patients with clinical and radiological findings suggestive of metastatic renal cell carcinoma who were ultimately diagnosed as have non-Hodgkin's lymphoma (5), germ cell tumor (1) or transitional cell carcinoma (1). Two of these patients presented with abdominal pain, gross hematuria and a flank mass. Computerized tomography was interpreted as showing renal cell carcinoma in all patients, although lymphoma and sarcoma were included in the differential diagnoses in 2. With the correct diagnosis and appropriate therapy, 4 of the 7 patients are currently disease-free. We emphasize the need for histological documentation in such patients in view of curative therapy available for possible underlying neoplasms simulating renal cell carcinoma. 相似文献
54.
CM Meireles J Czelusniak I Sampaio H Schneider SF Ferrari AF Coimbra-Filho A Pissinatti JA Muniz HS Ferreira MP Schneider 《Canadian Metallurgical Quarterly》1998,36(7-8):229-244
Five hundred forty-three blood samples from 15 populations of the four genera of callitrichin primates were studied electrophoretically. Polymorphism and genetic distances were estimated for 20 loci, 13 of which were polymorphic. The lion tamarin (Leontopithecus) studied here exhibited the least variability for these loci, while the monospecific Cebuella showed the most. The genetic distances observed between Callithrix and Cebuella genera support previous evidence indicating a close taxonomic relationship between them. Genetic distance values obtained in this study also support the synonimyzation of the kuhli form with Callithrix jacchus penicillata. 相似文献
55.
H Schneider I Sampaio ML Harada CM Barroso MP Schneider J Czelusniak M Goodman 《Canadian Metallurgical Quarterly》1996,100(2):153-179
Nuclear sequences of the 1.8 kilobase (kb) long intron 1 of the interstitial retinol-binding protein gene (IRBP), previously determined for 11 of the 16 extant genera of New World monkeys (superfamily Ceboidea, infraorder Platyrrhini), have now been determined for the remaining 5 genera. The maximum parsimony trees found, first with IRBP sequences alone and then with tandemly combined IRBP and epsilon-globin gene sequences from the same species, supported a provisional cladistic classification with the following clusters. Subtribes Callitrichina (Callithrix, Cebuella), Callimiconina (Callimico), Leontopithecina (Leontopithecus) and Saguina (Saguinus) constitute subfamily Callitrichinae, and subfamilies Callitrichinae, Aotinae (Aotus), and Cebinae (Cebus, Saimiri) constitute family Cebidae. Subtribes Chiropotina (Chiropotes, Cacajao) and Pitheciina (Pithecia) constitute tribe Pitheciini; and tribes Pitheciini and Callicebini (Callicebus) constitute subfamily Pitheciinae. Subtribes Brachytelina (Brachyteles, Lagothrix) and Atelina (Ateles) constitute tribe Atelini, and tribes Atelini and Alouattini (Alouatta) constitute subfamily Atelinae. The parsimony results were equivocal as to whether Pitheciinae should be grouped with Atelinae in family Atelidae or have its own family Pitheciidae. The cladistic groupings of extant ceboids were also examined by different stochastic evolutionary models that employed the same stochastic process of nucleotide substitutions but alternative putative phylogenetic trees on which the nucleotide substitutions occurred. Each model, i.e., each different tree, predicted a different multinomial distribution of nucleotide character patterns for the contemporary sequences. The predicted distributions that were closest to the actual observed distributions identified the best fitting trees. The cladistic relationships depicted in these best fitting trees agreed in almost all cases with those depicted in the maximum parsimony trees. 相似文献
56.
Requirements Engineering and Technology Transfer: Obstacles, Incentives and Improvement Agenda 总被引:1,自引:0,他引:1
Hermann Kaindl Sjaak Brinkkemper Janis A. Bubenko Jr Barbara Farbey Sol J. Greenspan Constance L. Heitmeyer Julio Cesar Sampaio do Prado Leite? Nancy R. Mead John Mylopoulos Jawed Siddiqi 《Requirements Engineering》2002,7(3):113-123
For many years, research results in requirements engineering (RE) have been developed without much interaction with, or impact
on, industrial practice. Why is it so difficult to introduce RE research results into mainstream RE practice? This paper attempts
to provide answers to this question by describing obstacles that researchers and practitioners have encountered when they
attempted technology transfer. In addition, major incentives for using RE methods are discussed, along with ideas for improving
current RE practice. The paper summarises, clarifies and extends the results of two panel discussions, one at the Twelfth
Conference on Advanced information Systems Engineering (CAiSE’00) and the other at the Fourth IEEE Conference on Requirements
Engineering (ICRE’00). 相似文献
57.
Nieke Michael Sampaio Gabriela Thm Thomas Seidl Christoph Teixeira Leopoldo Schaefer Ina 《Software and Systems Modeling》2022,21(1):225-247
Software and Systems Modeling - A product line is an approach for systematically managing configuration options of customizable systems, usually by means of features. Products are generated for... 相似文献
58.
Pablo Azevedo Sampaio Rodrigo da Silva Sousa Alessandro Nazário Rocha 《Journal of Intelligent and Robotic Systems》2018,91(2):219-231
Multi-Agent Patrolling Problems consist in moving agents throughout a graph in order to optimize a collective performance metric. Some strategies from the literature tackle this problem by dispatching decentralized autonomous agents that coordinate themselves merely by sensing and writing information in the nodes. In this work, they are called k-range local strategies, were k indicates the range, in number of edges, of the agents’ sensing capabilities. The 1-range strategies (where agents can sense up to its neighbor nodes) are certainly the most common case in the literature. And only few 0-range strategies (where agents can only sense its current node) were found, although this type of strategy has the advantage of requiring simpler hardware, when applied in the design of real robots. In this work, we propose two higher-level procedures to reduce the perception range of 1-range strategies to 0: the Zr Method and the EZr Method. Applying both methods in 1-range strategies found in the literature, we created twenty new 0-range strategies, which were evaluated in a simulation experiment described and analyzed here. We also developed a prototype of a low-cost patrolling robot that is able to run the 0-range strategies proposed in this work. 相似文献
59.
Carolina Kymie Vasques Nonaka Gabriela Louise Sampaio Luciana de Arago Frana Bruno Raphael Cavalcante Katia Nunes Silva Ricardo Khouri Felipe Guimares Torres Cassio Santana Meira Emanuelle de Souza Santos Carolina Th Macedo Bruno Diaz Paredes Vinicius Pinto Costa Rocha Silvia Regina Rogatto Ricardo Ribeiro dos Santos Bruno Solano de Freitas Souza Milena Botelho Pereira Soares 《International journal of molecular sciences》2021,22(7)
Chagas disease, caused by the parasite Trypanosoma cruzi (T. cruzi), remains a serious public health problem for which there is no effective treatment in the chronic stage. Intense cardiac fibrosis and inflammation are hallmarks of chronic Chagas disease cardiomyopathy (CCC). Previously, we identified upregulation of circulating and cardiac miR-21, a pro-fibrotic microRNA (miRNA), in subjects with CCC. Here, we explored the potential role of miR-21 as a therapeutic target in a model of chronic Chagas disease. PCR array-based 88 microRNA screening was performed in heart samples obtained from C57Bl/6 mice chronically infected with T. cruzi and serum samples collected from CCC patients. MiR-21 was found upregulated in both human and mouse samples, which was corroborated by an in silico analysis of miRNA-mRNA target prediction. In vitro miR-21 functional assays (gain-and loss-of-function) were performed in cardiac fibroblasts, showing upregulation of miR-21 and collagen expression upon transforming growth factor beta 1 (TGFβ1) and T. cruzi stimulation, while miR-21 blockage reduced collagen expression. Finally, treatment of T. cruzi-infected mice with locked nucleic acid (LNA)-anti-miR-21 inhibitor promoted a significant reduction in cardiac fibrosis. Our data suggest that miR-21 is a mediator involved in the pathogenesis of cardiac fibrosis and indicates the pharmacological silencing of miR-21 as a potential therapeutic approach for CCC. 相似文献
60.
Ranulfo M. Carneiro Neto Alireza Akhavan-Safar Eduardo M. Sampaio Joaquim T. Assis Lucas F. M. da Silva 《应用聚合物科学杂志》2021,138(47):51387
Viscous flow that often occurs in adhesive materials leads to a permanent deformation when adhesives are subjected to creep loading. Creep loading has a significant influence on the strength of bonded structures. Due to the viscous behavior, the fracture energy also may change with time for joints that experience creep loading in service. In this work the effects of two creep parameters (creep load and time) on the residual mode II fracture energy of an adhesive was investigated using end notched flexure (ENF) specimens. To achieve this, ENF samples were subjected to different creep loading levels at different creep times followed by quasi static tests to obtain the residual shear fracture energy of the adhesive. Experimental results showed that pre-creep loading of the bonded structures can significantly improve the fracture energy and the static strength of the joints. 相似文献