758 research outputs found
Análisis de viscocidad en lubricantes mediante diseño factorial con tres factores
In the field of statistics, the experimental design becomes an analysis tool to establish the ideal conditions of a very important process and / or product, analysis of variance it is very useful in cases where there are a series of controllable factors and that affect a complex process in order to optimize them, in the specific case, it is sought to give a solution to a lubricants analysis using a factorial design. For the development of the following document, it is proposed to show the analysis performed on lubricant samples by means of a 3 x 22 factorial design with 9 replicas. The analysis was performed on 108 samples, taking into account three different types of lubricants; which were subjected to a temperature of 40 degrees Celsius by kinematic viscocity test. It was observed in the analysis that taking into account the factors that interacted in the design (types of lubricant, parts, brands), only one of them showed significant interaction. The use of the design of factorial experiments is considered pertinent, since this can be useful in making maintenance decisions when buying a specific lubricant brand. The experiment design was carried out with StatGraphics statistical software. © 2018 Latin American and Caribbean Consortium of Engineering Institutions. All rights reserved
Removal efficiency of nitrate, phosphate, fecal and total coliforms by horizontal subsurface flow-constructed wetland from domestic wastewater
Background: Constructed wetlands are systems designed based on the utilization of natural processes,
including vegetation, soil, and their associated microbial assemblage to assist in treating different types
of wastewater.
Methods: Two local Appalachian plants (Louis latifolia and Phragmites australis) were planted into smallscale constructed wetlands to treat domestic wastewater in the North of Iran. The influent wastewater
and the effluent from each wetland were sampled daily for 120 days. Experiments were conducted based
on the mean ± standard deviation (SD) by analysis of variance (ANOVA).
Results: It was found that nitrate, phosphate, fecal and total coliforms were reduced by 84.4%, 94.4%,
96.3%, 93.9% for P. australis and 73.3%, 64.0%, 94.4%, 92.1% for L. latifolia, respectively.
Conclusion: According to the results, by using the HF-CW technology with L. latifolia and P. australis
plants, the treated wastewater fully meets the wastewater discharge parameters of WHO standards
Assessment of the impacts of the drought response program in the provision of emergency livestock and water interventions in preserving pastoral livelihoods in northern Kenya
Understanding decision quality through satisfaction
"PAAMS 2014 International Workshops, Salamanca, Spain, June 4-6, 2014. Proceedings"One of the most important factors to determine the success of an or-ganization is the quality of decisions made. In order to improve the decisions taken and to strengthen the competitiveness of organizations, systems such as Group Decision Support Systems (GDSSs) have been strongly developed and studied in recent decades. The amount of GDSSs incorporating automatic nego-tiation mechanisms, such as argumentation, is increasing nowadays. The evalu-ation of these mechanisms and the understanding of their real benefits for the organizations is still a hard challenge. In this article, we propose a model that allows a GDSS to measure the participant’s satisfaction with the decision, con-sidering aspects such as problem evaluation, personality, emotions and expecta-tions. This model is intended to enable the understanding of the decision’s qual-ity achieved with an argumentation system and to evaluate its capability to po-tentiate the decision’s quality. The proposed model validates all the assump-tions found in the literature regarding the participant’s satisfaction.This work is supported by FEDER Funds through the “Programa Operacional Fac-tores de Competitividade - COMPETE” program and by National Funds through FCT “Fundação para a Ciência e a Tecnologia” under the project: FCOMP-01-0124-FEDER-PEst-OE/EEI/UI0760/2011 and SFRH/BD/89697/2012
Effect of natural zeolite on live weight changes, ruminal fermentation and nitrogen metabolism of ewe lambs
The objective of this study was to evaluate the effects of natural zeolite on the performance and nitrogen metabolism of Rambouillet ewe lambs. Forty Rambouillet ewe lambs with an initial weight of 41.06 ± 3.9 kg were randomly assigned to one of four experimental diets, namely 0, 20, 40 and 60 g of natural zeolite (Comercializadora Omega® México) per kg dietary dry matter in a completely randomized design and sixteen ewe lambs were used in a 4 x 4 Latin square metabolism study. Performance was not modified by natural zeolite levels in the diet, and daily gain showed a quadratic response. Ammonia concentration at 8 and 12 hours increased linearly with zeolite. Zeolite increased ruminal pH linearly at 8 and 12 hours. Acetate and butyrate presented a quadratic response, and total ruminal volatile fatty acid concentration was linearly increased by zeolite. Nitrogen retention showed a linear and quadratic response to zeolite. The estimated fractions of protein digested in the small intestine, when rumen-fermentable energy was limiting (PDIE) and when rumen-fermentable nitrogen was limiting, showed a linear and quadratic response to zeolite. PDIE was positively correlated (r = 0.96) with average daily gain.Keywords: Sheep, ammonium, ruminal fermentation, productive, soluble nitroge
Cooperative Jahn-Teller transition and resonant x-ray scattering in thin film
Epitaxial thin films of stoichiometric were grown on substrates using the pulsed laser deposition technique. From the
high resolution x-ray diffraction measurements, the lattice parameters were
determined as a function of temperature and the cooperative Jahn-Teller
transition was found to occur at =573.0 K. Also measured was resonant
x-ray scattering intensity of the orthorhombic (100) peak of
near the Mn K edge from low temperatures to above . We demonstrate that
the integrated intensity of the (100) peak is proportional to the 3/2 power of
the orthorhombic strain at all temperatures, and thus provide an experimental
evidence that the resonant scattering near the Mn K edge in is
largely due to the Jahn-Teller effect.Comment: 13 pages, 4 figure
The Inflammatory Profile of CTEPH-Derived Endothelial Cells Is a Possible Driver of Disease Progression
Chronic thromboembolic pulmonary hypertension (CTEPH) is a form of pulmonary hypertension characterized by the presence of fibrotic intraluminal thrombi and causing obliteration of the pulmonary arteries. Although both endothelial cell (EC) dysfunction and inflammation are linked to CTEPH pathogenesis, regulation of the basal inflammatory response of ECs in CTEPH is not fully understood. Therefore, in the present study, we investigated the role of the nuclear factor (NF)-κB pro-inflammatory signaling pathway in ECs in CTEPH under basal conditions. Basal mRNA levels of interleukin (IL)-8, IL-1β, monocyte chemoattractant protein-1 (MCP-1), C-C motif chemokine ligand 5 (CCL5), and vascular cell adhesion molecule-1 (VCAM-1) were upregulated in CTEPH-ECs compared to the control cells. To assess the involvement of NF-κB signaling in basal inflammatory activation, CTEPH-ECs were incubated with the NF-κB inhibitor Bay 11-7085. The increase in pro-inflammatory cytokines was abolished when cells were incubated with the NF-κB inhibitor. To determine if NF-κB was indeed activated, we stained pulmonary endarterectomy (PEA) specimens from CTEPH patients and ECs isolated from PEA specimens for phospho-NF-κB-P65 and found that especially the vessels within the thrombus and CTEPH-ECs are positive for phospho-NF-κB-P65. In summary, we show that CTEPH-ECs have a pro-inflammatory status under basal conditions, and blocking NF-κB signaling reduces the production of inflammatory factors in CTEPH-ECs. Therefore, our results show that the increased basal pro-inflammatory status of CTEPH-ECs is, at least partially, regulated through activation of NF-κB signaling and potentially contributes to the pathophysiology and progression of CTEPH
Exploring morphological correlations among H2CO, 12CO, MSX and continuum mappings
There are relatively few H2CO mappings of large-area giant molecular cloud
(GMCs). H2CO absorption lines are good tracers for low-temperature molecular
clouds towards star formation regions. Thus, the aim of the study was to
identify H2CO distributions in ambient molecular clouds. We investigated
morphologic relations among 6-cm continuum brightness temperature (CBT) data
and H2CO (111-110; Nanshan 25-m radio telescope), 12CO (1--0; 1.2-m CfA
telescope) and midcourse space experiment (MSX) data, and considered the impact
of background components on foreground clouds. We report simultaneous 6-cm H2CO
absorption lines and H110\alpha radio recombination line observations and give
several large-area mappings at 4.8 GHz toward W49 (50'\times50'), W3
(70'\times90'), DR21/W75 (60'\times90') and NGC2024/NGC2023 (50'\times100')
GMCs. By superimposing H2CO and 12CO contours onto the MSX color map, we can
compare correlations. The resolution for H2CO, 12CO and MSX data was about 10',
8' and 18.3", respectively. Comparison of H2CO and 12CO contours, 8.28-\mu m
MSX colorscale and CBT data revealed great morphological correlation in the
large area, although there are some discrepancies between 12CO and H2CO peaks
in small areas. The NGC2024/NGC2023 GMC is a large area of HII regions with a
high CBT, but a H2CO cloud to the north is possible against the cosmic
microwave background. A statistical diagram shows that 85.21% of H2CO
absorption lines are distributed in the intensity range from -1.0 to 0 Jy and
the \Delta V range from 1.206 to 5 km/s.Comment: 18 pages, 22 figures, 5 tables. Accepted to be published in
Astrophysics and Space Scienc
Fluctuating brane in a dilatonic bulk
We consider a cosmological brane moving in a static five-dimensional bulk
spacetime endowed with a scalar field whose potential is exponential. After
studying various cosmological behaviours for the homogeneous background, we
investigate the fluctuations of the brane that leave spacetime unaffected. A
single mode embodies these fluctuations and obeys a wave equation which we
study for bouncing and ever-expanding branes.Comment: 17 pages, 7 figures, revte
Interface Depinning in the Absence of External Driving Force
We study the pinning-depinning phase transition of interfaces in the quenched
Kardar-Parisi-Zhang model as the external driving force goes towards zero.
For a fixed value of the driving force we induce depinning by increasing the
nonlinear term coefficient , which is related to lateral growth, up to
a critical threshold. We focus on the case in which there is no external force
applied (F=0) and find that, contrary to a simple scaling prediction, there is
a finite value of that makes the interface to become depinned. The
critical exponents at the transition are consistent with directed percolation
depinning. Our results are relevant for paper wetting experiments, in which an
interface gets moving with no external driving force.Comment: 4 pages, 3 figures included, uses epsf. Submitted to PR
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