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Hydrodynamics of the interceptor on a 2-D flat plate by CFD and experiments

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journal of Hydrodynamics 2015年第6期27卷 919-933页

作者： mANSOORI m. fernandes A.C. Department of Naval and Ocean Engineering Federal University of Rio de Janeiro

Nowadays, the use of interceptor by both partial and total dynamic lift crafts is quite common. In this article, a lot of evidence is given regarding the effectiveness of interceptor. The interceptor, when placed at the stern region, changes the pressure distribution around the craft. Its presence affects drag force, lifting force and the position of pressure＇s center leading to a new trim. This study focuses on hydrodynamic effects of interceptors on a 2-D fiat plate based on both computational fluid dynamic （CFD） and experimental approaches. The Reynolds average Navier-Stokes （RANS） equations are used to model the flow around a fixed flat plate with an interceptor at different heights and attack angles. based on finite volume method and SImPLE algorithm which uses static structures, this model can be analyzed and the RANS results can be compared with the experimental data obtained in the current channel of the laboratory of waves and current of COPPE/UFRj （LOC in Portuguese acronym）. According to the results, the increase of pressure at the end of the flat plate was proportional to the interceptor height. In addition, the existence of interceptors can significantly increase the lift force coefficient at high angles of attack also proportional to the interceptor height. The presence of interceptor at the end of the fiat plate increased both the lift coefficient and the drag coefficient but hydrodynamic drag did not grow as fast as the lift coefficient did. The lift coefficient increased much more. Furthermore, the results showed that the interceptor effectiveness is proportional to the boundary layer thickness at the end of the fiat plate. As the interceptor was inside the boundary layer alterations of flow speed led to changes in boundary layer thickness, directly affecting interceptor＇s efficiency. Optimum choice of interceptor height had a great effect on its efficiency, and in choosing it the flow speed and length of the boat must be taken into consideration.

关键词： interceptor craft 2-D fiat plate lifting coefficient Reynolds average Navier-Stokes (RANS) pressure distribution,computational fluid dynamic drag

Effect of Noisy Fitness in Real-Time Strategy Games Player behaviour Optimisation Using Evolutionary Algorithms

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journal of Computer Science & Technology 2012年第5期27卷 1007-1023页

作者： Antonio m. mora Antonio Fernndez-Ares juan j. merelo Pablo García-Snchez Carlos m. fernandes Computer Architecture and Technology Department University of Granada Institute for Systems and Robotics Technical University of Lisbon

This paper investigates the performance and the results of an evolutionary algorithm （EA） specifically designed for evolving the decision engine of a program （which, in this context, is called bot） that plays Planet Wars. This game, which was chosen for the Google Artificial Intelligence Challenge in 2010, requires the bot to deal with multiple target planets, while achieving a certain degree of adaptability in order to defeat different opponents in different scenarios. The decision engine of the bot is initially based on a set of rules that have been defined after an empirical study, and a genetic algorithm （GA） is used for tuning the set of constants, weights and probabilities that those rules include, and therefore, the general behaviour of the bot. Then, the bot is supplied with the evolved decision engine and the results obtained when competing with other bots （a bot offered by Google as a sparring partner, and a scripted bot with a pre-established behaviour） are thoroughly analysed. The evaluation of the candidate solutions is based on the result of non-deterministic battles （and environmental interactions） against other bots, whose outcome depends on random draws as well as on the opponents＇ actions. Therefore, the proposed GA is dealing with a noisy fitness function. After analysing the effects of the noisy fitness, we conclude that tackling randomness via repeated combats and reevaluations reduces this effect and makes the GA a highly valuable approach for solving this problem.

关键词： real-time strategy game genetic algorithm noisy fitness player behaviour optimisation parameter adaptation

An Adaptive Load Stepping Algorithm for Path-Dependent Problems based on Estimated Convergence Rates

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Computer modeling in Engineering & Sciences 2017年第3期113卷 325-342页

作者： m.T.C.Araújo fernandes C.O.Cardoso W.j.mansur Civil Engineering Department/COPPE/Federal University of Rio de janeiro Ilha do FundaoP.B.6850621945-970 Rio de JaneiroRJBrazil Petrobras/Cenpes Av.Horácio Macedo950Ilha do Fundao21941-915 Rio de JaneiroRJBrazil Civil Engineering Department/COPPE/Federal University of Rio de janeiro Ilha do FundaoP.B.6850621945-970 Rio de JaneiroRJBrazil

A new adaptive(automatic)time stepping algorithm,called RCA(Rate of Convergence Algorithm)is *** new algorithm was applied in nonlinear finite element analysis of path-dependent *** step size is adjusted by monitoring the estimated convergence rate of the nonlinear iterative *** RCA algorithm is relatively simple to implement,robust and its performance is comparable to,and in some cases better than,the automatic load incrementaion algorithm existent in commercial *** about the convergence rate of nonlinear iterative processes,an estimation of the rate and a study of the parameters of the RCA algorithm are *** show the capacity of the algorithm to adjust the increment size,detailed discussions based on results for different limit load analyses are *** results obtained by RCA algorithm are compared with those by AbAQUS?,one of the most powerful nonlinear FEA(Finite Element Analysis)commercial software,in order to verify the capability of RCA algorithm to adjust the increment size along nonlinear analyses.

关键词： Rate of convergence nonlinear automatic load incrementation limit load

Effect of Combined Use of brackish Water and Nitrogen Fertilizer on biomass and Sugar Yield of Sweet Sorghum

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Pedosphere 2012年第6期22卷 785-794页

作者： T.b.RAmOS N.L.CASTANHEIRA m.C.GONALVES m.L.fernandes m.I.jANURIO m.E.LOURENO F.P.PIRES j.C.mARTINS CEER-biosystems Engineering Institute of Agronomy Technical University of Lisbon Tapada da Ajuda 1349-017 Lisbon (Portugal) Estao Agronómica Nacional L-INIA Instituto Nacional de Recursos Biológicos Quinta do Marquês Av. República 2784-505 Oeiras (Portugal) Departamento de Fitotecnia Instituto de Ci encias Agrrias e Ambientais Mediterrnicas Universidade de vora Apartado 94 7002-554 vora (Portugal)

Soil salinization and non-point source pollution are among the most important and widespread environmental problems in European mediterranean regions. Sweet sorghum （Sorghum bicolor （L.） moench var. saccharatum） is a moderate to high salinity tolerant crop with low water and nutrient needs, seen as an alternative to grow in the water scarce regions. A three-year multifactorial study was conducted in southern Portugal to evaluate the combined effects of saline water and nitrogen application on the dry biomass （total, stems, and leaves）, sugar content （total reducing sugars and sucrose eontents） and sugar yield （here defined as the product of total reducing sugars and stems dry biomass） functions of sweet sorghum. Sorghum dry biomass and sugar yield showed diminishing returns for each incremental change of nitrogen. The use of saline irrigation waters also led to yield reduction. Exception was sucrose content which increased with increasing levels of sodium in the soil. Nitrogen need decreased as the amount of sodium applied increased. Stem dry biomass, sucrose content, and sugar yield progressively increased with progress in the experiment. The effect could be attributed to the increase of the amount of irrigation applied throughout the years, thus increasing the leaching fraction which promoted salt leaching from the root zone, reduced the salinity stress, increased plant transpiration, nitrogen uptake and biomass yield.

关键词： mediterranean conditions non-point source pollution salinity sweet sorghum yield functions

Evaluation of Soil Quality Indicators in Sugarcane management in Sandy Loam Soil

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Pedosphere 2009年第3期19卷 312-322页

作者： S.A.C.SANT'ANNA m.F.fernandes W.m.P.m.IVO j.L.S.COSTA brazilian Agricultural Research Corporation (Embrapa Coastal Tablelands) Av. Beira Mar 3250 Aracaju SE 49025- 040 (Brazil) Departament of Physiology Universidade Federal de Sergipe So Cristóvo SE 49100-000 (Brazil) brazilian Agricultural Research Corporation (Embrapa Coastal Tablelands) Av. Beira Mar 3250 Aracaju SE 49025-040 (Brazil) brazilian Agricultural Research Corporation (Embrapa) brasília DF 70770-901 (Brazil)

An important factor for the sustainability of soils highly susceptible to degradation is the use of monitoring tools that promptly and realistically reflect changes imposed on soil by different cropping systems. To select soil quality indicator variables in sugarcane (Saccharum officinarum L.) production areas that fulfill the criteria of sensitivity to management practices and between-season consistency in the management discrimination, ten composite soil samples (0–10 cm) were collected in july 2005 (rainy season) and again in march 2006 (dry season) from areas under cultivation of organic sugarcane (OS), green sugarcane (GS), burned sugarcane (bS) and from an adjacent native forest (NF) area at Usina Triunfo, boca da mata, Alagoas, brazil. microbial biomass-C (mbC), total organic C (TOC), soil enzyme activity expressed as the rate of fluorescein diacetate (FDA) hydrolysis, mean weight diameter of water-stable soil aggregates (mWD), and percentage of water-stable macroaggregates (PWSA) were analyzed. Although mbC and TOC were higher in NF than in the cultivated areas, no differences were observed in these C pools between the three sugarcane systems. The response of FDA to the site management was dependent on the sampling time. In the rainy period, the activity followed the order: NF > OS > GS > bS, whereas in the dry season, only NF differed from the other treatments. Irrespective of the sampling time, mWD and PWSA decreased in the order NF > OS = GS > bS. The variables mWD and PWSA are quite sensitive for discriminating between site management histories regardless the sampling season.

关键词： fiuorescein diacetate green-sugarcane organic matter management sugarcane (Saccharum ojficinarum L.) sustainable agricultural use

Effect of periodic heat transfer on the transient thermal behavior of a convective-radiative fully wet porous moving trapezoidal fin

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Applied mathematics and mechanics(English Edition) 2023年第4期44卷 653-668页

作者： b.j.GIREESHA m.L.KEERTHI Department of PG Studies and Research in mathematics Kuvempu UniversityShankaraghatta 577451India

A moving trapezoidal profiled convective-radiative porous longitudinal fin wetted in a single-phase fluid is considered in the current *** periodic variation in the fin base temperature is taken into account along with the temperature sensitive thermal conductivity and convective heat transfer *** modeled problem,which is resolved into a non-linear partial differential equation(PDE),is made dimensionless and solved by employing the finite difference method(FDm).The results are displayed through graphs and *** effects of amplitude,frequency of oscillation,wet nature,Peclet number,and other relevant quantities on the distribution of temperature through the fin length and with the dimensionless time are *** is deciphered that the periodic heat transfer gives rise to the wavy nature of the fin thermal profile against *** analysis is beneficial in the design of fin structures for applications like solar collectors,space/airborne applications,and refrigeration industries.

关键词： convection fully wet porous fin trapezoidal profile moving fin unsteady periodic thermal condition

Uniform Query Framework for Relational and NoSQL Databases

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Computer modeling in Engineering & Sciences 2017年第2期113卷 171-181页

作者： j.b.Karanjekar m.b.Chandak Shri Ramdeobaba College of Engineering and management NagpurIndia and Izel Technologies Pvt Ltd.PuneIndia Shri Ramdeobaba College of Engineering and management NagpurIndia

As the data managed by applications has evolved over the years with the arrival of Web 2.0,a large number of new databases have been developed to manage various types of *** the traditional relational databases continue to exist,NoSQL databases which are document oriented or key-value stores or columnar continue to evolve and are embraced very rapidly across the *** is not just the type of data handled by these databases that is different but also the query language they use is also *** paper talks about a uniform query framework that can be used for traditional relational databases and NoSQL *** query framework can also perform joins,aggregates,filter on data from various data sources in a single query.

关键词： NoSQL RDbmS data tetrieval inter-database joins SQL Cassandra mongoDb Calcite mySQL

Fiber Cavity Ring-Down Using an Optical Time-Domain Reflectometer

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Photonic Sensors 2014年第4期4卷 295-299页

作者： D. j. PASSOS S. O. SILVA j. R. A. fernandes m. b. mARQUES O. FRAZAO INESC Porto Rua do Campo Alegre 687 4169-007 Porto Portugal and Dept. de Fisica e Astronomia da Faculdade deCiOncias da Universidade do Porto Rua do Campo Alegre 687 4169-007 Porto Portugal Departamento de Fisica Escola de Ci~ncias e Tecnologia Universidade de Tr6s-os-Montes e Alto Douro Quinta dePrados 5001-801 Vila Real Portugal

This work presented a demonstration of the potential for a fiber based cavity ring-down （CRD） using an optical time-domain reflectometer （OTDR）. The OTDR was used to send the impulses down into about 20km of a standard single optical fiber, at the end of which the fiber cavity ring-down was placed. The OTDR measured no appreciable losses, so other CRDs multiplexed could be spliced in parallel along the same optical fiber. To demonstrate the behavior and sensitivity of the proposed configuration, a displacement sensor based on a fiber taper with a diameter of 50 μm was placed inside the fiber loop, and the induced losses were measured on the CRD signal -- a sensitivity of 11.8 ＋ 0.5 μs/mm was achieved. The dynamic range of the sensing head used in this configuration was about 2 mm. Finally, this work was also compared with different works published in the literature.

关键词： Optical fiber sensors cavity ring-down OTDR

Cytokeratms and carcinoembryonic antigen in diagnosis,staging and prognosis of colorectal adenocarcinoma

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World journal of Gastroenterology 2005年第5期11卷 645-648页

作者： Luís C.fernandes Su b.Kim Delcio matos Coloproctology Sector of Surgical Gastroenterology Department UNIFESP-Escola Paulista de medicina Sao PauloBrazil

AIm: To evaluate the serum levels of cytokeratins and carcinoembryonic antigen (CEA) in diagnosis, staging and prognosis of patients with colorectal ***: The sample consisted of 169 patients. One hundred blood donors formed the control group. Radical surgery was performed on 120 patients, with an average follow-up duration of 22.3 mo. Relapses occurred in 23individuals after an average of 18.09 mo. CEA was assayed via the Delfia(R) method with a limit of 5 ng/mL. Cytokeratins were assayed via the LIA-mat(R) TPA-m Prolifigen(R) method with a limit of 72 U/***: In the diagnosis of patients with colorectal adenocarcinoma, CEA showed a sensitivity of 56%, a specificity of 95%, a positive predictive value of 94%, a negative predictive value of 50% and an accuracy of 76.8%.TPA-m had a sensitivity of 70%, a specificity of 96%, a positive predictive value of 97%, a negative predictive value of 66% and an accuracy of 93.6%. The elevation of one of the markers was shown to have a sensitivity of 76.9%, a specificity of 91%, a positive predictive value of 93.5%, a negative predictive value of 70% and an accuracy of 83.6%.There was no variation in the levels of the markers according to the degree of cell differentiation while there was an elevation in their concentrations in accordance with the increase in neoplastic dissemination. There was a statistically significant difference between the patients with stage Ⅳ lesions and those with stages Ⅰ, Ⅱ and Ⅲ *** regard to CEA, the averagelevel was 14.2 ng/mL in patients with stage Ⅰ lesions, 8.5 ng/mL in patients with stage Ⅱ lesions, 8.0 ng/mL in patients with stage Ⅲ lesions and 87.7 ng/mL in patients with stage Ⅳ lesions. In relation to TPA-m, the levels were 153.1 U/L in patients with stage Ⅰtumors, 106.5 U/L in patients with stage Ⅱ tumors, 136.3 U/L in patients with stage Ⅲ tumors and 464.3 U/L in patients with stage Ⅳ tumors. There was a statistical difference in patients with a high CEA level

关键词： Colorectal adenocarcinoma Cytokeratins Carcinoembryonic antigen