5,452 research outputs found
Assessment of lot shape in business park design
Planning and developing a business park is a complex task, whichdemands integration across various
fields of design and knowledge. The first choice to be made in the design process is relate to the zoning process
and the definition of the lot layout and landscape. These first decisions will constrain all subsequent decisions
concerning utilities, facilities and amenities. For this reason, the assessment of those issues is crucial for the
perception of the overall quality of the business park design. The main goal of this work is to present a simple
indicator which can assess the lot shape in order to optimize the building form and costs, the use of its open
areas, the layout and the economic spacing of roads and the service routes. The indicator lot shape evaluatesthe
performance of the lot design solutions according to the concept of compactness
Modeling of chemical wear in ferrous alloys/silicon nitride contacts during high speed cutting
The wear resistance of SisN4 in machining of iron alloys can be surprisingly low due to chemical affinity for dissolution in the metal. This limits the use of SisN4 inserts in high speed machining of steels, while Si3N4 retains the best performance of all cutting materials in turning of grey cast iron, a different ferrous alloy. The chemical wear of several ceramics has been investigated on the basis of dissolution in pure iron by Kramer and Suh. Nevertheless, the influence of alloy elements was not studied. In the present work, solid solution thermodynamics is applied to predict chemical wear of S&N4 by setting the influence of interaction coefficients of the alloy elements in the Henrian activity of Si and N in austenite. The model predicts the relative order of magnitude of the crater wear of SisN4 inserts in machining of tool steels, carbon steels and grey cast iron
Urban air dispersion model of a mid-sized city. Validation methodology
Viana do Castelo is a mid-sized city located on the northwest Portuguese seaside, which undertook the challenge of developing an environmental program leading to the integration in the Healthy Cities
European Network. Within this program includes prediction of pollutant concentration for NO2, CO, PM10,
O3 and C6H6. This paper presents the methodology developed to validate the modelled results. Predicted
concentrations were compared against measured concentrations of a chosen pollutant: Carbon Monoxide, CO.
The methodology adopted was based in BOOT statistical approach. Five comparison statistics were calculated
for three test points in order to find out the quality of the modelled results. Additionally, a hourly profile of
predicted versus measured concentrations was developed.(undefined
Validation study of urban air dispersion model of Viana do Castelo
The City of Viana do Castelo in Portugal has developed an air quality program, which includes
prediction of pollutant concentration for NO2, CO, PM10, O3 and C6H6. A range of numerical models were
used to produce the concentration maps: the ADMS-Urban model for the pollutants dispersion; the Hills
model to calculate air flow and turbulence over complex terrain, including the effects of variable surface
roughness; the CORINAIR v.5 to estimate traffic emissions.
This paper presents the methodology developed to validate the modelled results. Predicted concentrations
were compared against measured concentrations of a chosen pollutant: Carbon Monoxide, CO. Five
comparison statistics were calculated for three test points in order to find out the quality of the modelled
results. Additionally, a hourly profile of predicted versus measured concentrations was developed
Cascade MIMO P-PID controllers applied in an over-actuated quadrotor Tilt-Rotor
To map the Virtual Control Actions (VCAs) into
Real Control Actions (RCAs), over-actuated systems typically
require nonlinear control allocation methods. On embedded
robotic platforms, computational efforts are not always available.
With this in mind, this work presents the design of a
Quadrotor Tilt-Rotor (QTR) through a new concept of control
allocation with uncoupled RCAs, where a nonlinear system is
divided into partially dependent and linear subsystems with fast
and robust convergence. The RCAs are divided into smaller
and linearized sets and solved sequentially. Then, the cascade
Multipe-Input-Multipe-Output (MIMO) Proportional (P)-
Proportional, Integral and Derivative (PID) controllers tuning
were presented with saturation constants and successive loop
closure technique, where some open-field environment tests were
conducted to validate the respective tuning. In the end, it showed
to be reliable, robust, efficient, and applicable when VCAs are
overlapped between the subsystems.The authors would like to thank CEFET-MG and Leuphana
University of L¨uneburg for their financial support.info:eu-repo/semantics/publishedVersio
BioRePortAP, an electronic clinical record coupled with a database : an example of its use in a single
Aims: To evaluate the efficacy and safety of the treatment of psoriatic arthritis (PsA) patients with tumor necrosis factor (TNF) antagonists in the Rheumatology Department of Hospital de Santa Maria using the BioRePortAP.
Methods: The Portuguese Society of Rheumatology (SPR) developed an electronic medical chart coupled with a database for the follow up of PsA patients, the BioRePortAP, which was launched in May 2009. This evaluation was based on all the PsA patients that were on active treatment with TNF antagonists in September 2009 and were registered in the BioRePortAP. All the previous data on these patients were introduced in BioRePortAP using the prospective paper based follow up protocol that this Department was using since 1999. Only patients with more than 9 months of treatment were analyzed.
Results: Forty-two patients with PsA, actively treated with anti-TNF agents in September 2009, for at least 9 months, were analyzed in BioRePortAP. Twenty-three patients were male (55%) and nineteen were female (45%). The average age of these patients was 49.8±10.9 years old, the average disease duration was of 10.7±5.6 years and the mean duration of biological therapy was of 37.8±27.8 months. For the 81% of patients with peripheral joint disease there was a mean reduction of more than 80% in the swollen and tender joint counts, and almost 50% in the health assessment questionnaire (HAQ) value. In the 19% of the patients with axial involvement the reduction of BASDAI and BASFI was not statistically significative. On top of that, PASI score suffered a reduction of 64%. Fourteen patients (33.3%) had to switch their TNF antagonist treatment. 58.8% of the switches were due to adverse effects and 41.2% due to therapy failure. Regarding the 56 adverse reactions registered, only one was a severe reaction. The remaining adverse reactions were not severe and 67% of them were due to infections.
Discussion: The results of this first report of the use of the BioRePortAP in clinical practice confirm the efficacy and safety of TNF antagonist treatment in PsA. The results shown here elucidate the potential applications of BioRePortAP as a tool for efficacy and safety assessment of PsA patients treated with biotechnological drugs
A new gravitational N-body simulation algorithm for investigation of cosmological chaotic advection
Recently alternative approaches in cosmology seeks to explain the nature of
dark matter as a direct result of the non-linear spacetime curvature due to
different types of deformation potentials. In this context, a key test for this
hypothesis is to examine the effects of deformation on the evolution of large
scales structures. An important requirement for the fine analysis of this pure
gravitational signature (without dark matter elements) is to characterize the
position of a galaxy during its trajectory to the gravitational collapse of
super clusters at low redshifts. In this context, each element in an
gravitational N-body simulation behaves as a tracer of collapse governed by the
process known as chaotic advection (or lagrangian turbulence). In order to
develop a detailed study of this new approach we develop the COsmic LAgrangian
TUrbulence Simulator (COLATUS) to perform gravitational N-body simulations
based on Compute Unified Device Architecture (CUDA) for graphics processing
units (GPUs). In this paper we report the first robust results obtained from
COLATUS.Comment: Proceedings of Sixth International School on Field Theory and
Gravitation-2012 - by American Institute of Physic
Avaliação de zonas de criticidade acústica: aplicação das potencialidades de um SIG na avaliação do ruído de uma cidade de média dimensão
O crescimento urbano, pelas dimensões que actualmente assume, vem exercendo pressões de forma continuada nos recursos, nas infra-estruturas e nos equipamentos, afectando negativamente o standard de vida dos cidadãos. Neste contexto, a avaliação e monitorização da qualidade do ambiente urbano tornou se um tema de primordial importância quando considerado como um instrumento de apoio à decisão para a construção de cidades mais sustentáveis e com melhor qualidade de vida. Viana do Castelo é uma cidade de média dimensão localizada no litoral norte de Portugal e que aceitou o desafio de desenvolver uma programa para a melhoria da qualidade do seu ambiente urbano, com o objectivo de aderir ao Projecto Cidades Saudáveis e integrar a Rede Europeia das Cidades Saudáveis. Neste programa, a caracterização do ruído urbano, nomeadamente a determinação dos níveis de intensidade sonora na zona urbana e da exposição da população ao ruído ambiente, foi considerada uma das acções prioritárias. A ferramenta adoptada para desenvolver estes estudos inclui modelos de previsão de ruído numa plataforma de SIG. Com base em dados de tráfego e nas características físicas do local foram desenvolvidos mapas de ruído e procedeu-se ao seu cruzamento com o zonamento acústico do território e com a população residente. Esta combinação foi a base para a identificação das zonas de criticidade acústica, em termos de níveis de ruído e dos índices de exposição da população a esses níveis de ruído. O presente artigo apresenta uma abordagem deste problema, passando pelos fundamentos teóricos e pelo estudo desenvolvido para a cidade de Viana do Castelo
Use of data mining techniques to explain the primary factors influencing water sensitivity of asphalt mixtures
The water sensitivity of asphalt mixtures affects the durability of the pavements, and it depends on several parameters related to its composition (aggregates and binder) and the production and application processes. One of the main parameters used in the European Standards to measure the water sensitivity of asphalt mixtures is the indirect tensile strength ratio (ITSR). Therefore, this work aims to obtain a predictive model of ITSR of asphalt mixtures using several parameters that affect water sensitivity and assess their relative importance. The database used to develop the model comprises thirteen parameters collected from one hundred sixty different asphalt mixtures. Data Mining techniques were applied to process the data using Multiple Regression, Artificial Neural Networks, and Support Vector Machines (SVM). The different metrics analysed showed that SVM is the best predictive model of the ITSR (mean absolute deviation of 0.116, root mean square error of 0.150 and Pearson correlation coefficient of 0.667). The application of a sensitivity analysis indicates that the binder content is the parameter that most influences the water sensitivity of asphalt mixtures (26%). However, this property depends simultaneously on other factors such as the characteristics of the coarse and fine aggregates (24.9%), asphalt binder characteristics (19.3%) and the use of additives (10%).Acknowledgements This work was partly financed by FCT/MCTES through national funds (PIDDAC) under the R & D Unit Institute for Sustainability and Innovation in Structural Engineering (ISISE) , under reference UIDB/04029/2020
Cleaning activity among Labridae in the Azores: the rainbow wrasse Coris julis and the Azorean blue wrasse Centrolabrus caeruleus
Copyright © Cambridge University Press 2009.Cleaning interactions among the rainbow wrasse Coris julis and the azorean blue wrasse Centrolabrus caeruleus are presented with photographic registers, as well as the first record of the latter cleaning conspecifics from Azorean shallow rocky reefs
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