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81.
This paper considers assessment techniques based on the use of questionnaires, assessment matrices, workshops, and pro-forma assessment schemas; together with people issues such as motivation and involvement. With strong reference to SPICE process capability levels and the European Foundation for Quality Management (EFQM) Excellence Model, the authors suggest a novel framework containing a possible sequence of improvement steps towards the Established Level 3. The main conclusion in this paper is that an incremental improvement path can be defined using process assessment that commences with questionnaires, then goes on to matrices, workshops, and finally reaches pro-formas. Furthermore, it seems quite plausible that all four types of assessment techniques should be employed on an ongoing basis in a staged fashion. 相似文献
82.
Julio Cesar Sampaio do Prado Leite Jorge Horacio Doorn Graciela D. S. Hadad Gladys N. Kaplan 《Requirements Engineering》2005,10(1):1-21
Scenarios help practitioners to better understand the requirements of a software system as well as its interface with the environment. However, despite their widespread use both by object-oriented development teams and human–computer interface designers, scenarios are being built in a very ad-hoc way. Departing from the requirements engineering viewpoint, this article shows how inspections help software developers to better manage the production of scenarios. We used Fagans inspections as the main paradigm in the design of our proposed process. The process was applied to case studies and data were collected regarding the types of problems as well as the effort to find them.
相似文献
Julio Cesar Sampaio do Prado LeiteEmail: Fax: +55-21-31141530 |
83.
P. A. B. De Sampaio 《International journal for numerical methods in engineering》1991,31(6):1135-1149
A new Petrov-Galerkin method for the incompressible Navier-Stokes equations is presented. The use of the so-called ‘optimal upwind’ parameter in multidimensions is justified by a time-scale analysis of the relevant physical processes. The resulting procedure circumvents the Babu?ka-Brezzi condition and allows equal order interpolation for velocity and pressure to be used. 相似文献
84.
Ala-Phe-Lys-CH2-Cl is a chloromethylketone derivative which is able to promote the inhibition of several proteolytic enzymes. In this paper the inhibition of horse urinary and plasmatic kallikreins is described and this inhibition is compared to that produced in human plasma kallikrein. This compound was designed based upon the structure of bradykinin. This enzyme substrate system can provide a model for the study of the interactions between bradykinin and its receptor. The inhibition of the enzymes was achieved both for its esterase and kinin-releasing activities. 相似文献
85.
Paulo A.B. de Sampaio Jos L.H. Faccini Jian Su 《International Journal of Heat and Mass Transfer》2008,51(11-12):2752-2761
This paper reports numerical and experimental investigation of stratified gas–liquid two-phase flow in horizontal circular pipes. The Reynolds averaged Navier–Stokes equations (RANS) with the k–ω turbulence model for a fully developed stratified gas–liquid two-phase flow are solved by using the finite element method. A smooth interface surface is assumed without considering the effects of the interfacial waves. The continuity of the shear stress across the interface is enforced with the continuity of the velocity being automatically satisfied by the variational formulation. For each given interface position and longitudinal pressure gradient, an inner iteration loop runs to solve the non-linear equations. The Newton–Raphson scheme is used to solve the transcendental equations by an outer iteration to determine the interface position and pressure gradient for a given pair of volumetric flow rates. Favorable comparison of the numerical results with available experimental results indicates that the k–ω model can be applied for the numerical simulation of stratified gas–liquid two-phase flow. 相似文献
86.
Loureiro S Sampaio A Brandão A Nogueira AJ Soares AM 《The Science of the total environment》2006,369(1-3):119-128
Soil decomposition is mainly dependent on the nature and characteristics of organic matter within the soil, the environmental conditions and the activity of microorganisms and soil fauna. Isopods play an important role in decomposition through litter fragmentation and stimulating and/or ingesting fungi and bacteria. The aim of this study was to jointly evaluate the effect of different food types and the effect of heavy metal contamination of those foods through isopod feeding performance assays. These studies used the terrestrial isopod Porcellionides pruinosus. After feeding with different leaf types for the study on feeding performance, alder leaves were chosen for the contamination experiments. Feeding parameters like consumption, assimilation, egestion and growth ratios were calculated and compared among treatments and food type. Lower quality food decreased isopods performance. Exotic food types were shown to be less preferred than alder or oak leaves. Contaminated food also resulted in a decrease in performance among the feeding parameters studies, although isopods can tolerate in certain cases high amounts of heavy metals. For this reason it is possible that in future this crustacean can be used as bioindicators of soil contamination or in the evaluation of contaminated sites or remediation processes. 相似文献
87.
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
88.
89.
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
90.
A review of scalability and topological stability issues in IEEE 802.11s wireless mesh networks deployments
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Scalability and topological stability are two of the most challenging issues in current wireless mesh networks (WMNs) deployments. In the literature, both the scalability and the topological stability of WMNs are described as likely to suffer from poor performance due to the ad hoc nature of the underlying IEEE 802.11 mechanisms. The main contribution of this article is a comprehensive review of the main topological stability and scalability‐related issues in IEEE 802.11s‐based networks. Moreover, the most relevant proposed solutions are surveyed, where both the drawbacks and the merits of each proposal are highlighted. At the end of the article, some open research challenges are presented and discussed. It is expected that this work may serve as motivation for more and deeper research on these issues to allow the design of future more stable and scalable IEEE 802.11s mesh networks deployments. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献