2,199 research outputs found
Fuzzy set applications in engineering optimization: Multilevel fuzzy optimization
A formulation for multilevel optimization with fuzzy objective functions is presented. With few exceptions, formulations for fuzzy optimization have dealt with a one-level problem in which the objective is the membership function of a fuzzy set formed by the fuzzy intersection of other sets. In the problem examined here, the goal set G is defined in a more general way, using an aggregation operator H that allows arbitrary combinations of set operations (union, intersection, addition) on the individual sets Gi. This is a straightforward extension of the standard form, but one that makes possible the modeling of interesting evaluation strategies. A second, more important departure from the standard form will be the construction of a multilevel problem analogous to the design decomposition problem in optimization. This arrangement facilitates the simulation of a system design process in which different components of the system are designed by different teams, and different levels of design detail become relevant at different time stages in the process: global design features early, local features later in the process
A Simple Dynamic Model of Credit and Aggregate Demand
The purpose of the paper is to present a tractable model of an old topic which is becoming more important in macroeconomics: the link between financial structure and economic activity.Aggregate Demand, Fiscal Policy, Monetary Policy, moral hazard, adverse selection, suuply of credit, reserves.
A CONCEPT FOR A MATERIAL THAT SOFTENS WITH FREQUENCY
ABSTRACT This work presents design concepts to synthesize composite materials with special dynamic properties, namely, materials that soften at high frequencies. Such dynamic properties are achieved through the use of a two-phase material that has inclusions of a viscoelastic material of negative elastic modulus in a typical matrix phase that has a positive elastic modulus. A possible realization of the negative stiffness inclusion phase is presented. A numerical homogenization technique is used to compute the average viscoelastic properties of the composite. The method and the properties of a composite material designed with it are demonstrated through an example
A method of grid optimization for finite element methods
A computationally useful criterion for grid optimization is derived, based on a measure of the interpolation error associated with the finite element model. The result is intended to be used to improve the quality of finite element solutions by changing the location of the nodes within a fixed number of degrees of freedom. Examples of the application of the criterion are provided.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/25064/1/0000495.pd
SĂndrome de fatiga crĂłnica en una adolescente de 15 años
Fatigue and lack of energy are frequent symptoms in children and adolescents. A
diagnosis of chronic fatigue syndrome should be considered in children and
adolescents who complain of chronic fatigue associated with other symptoms
without a demonstrable physical cause. Lack of knowledge about this syndrome and
late diagnosis may have a negative impact on the normal development of affected
children and adolescents. Treatment should be based on a rehabilitation program
with cognitive behavioral therapy and a gradual increase in activities
Systematic Procedure to Avoid Unintended Polarity Mismatch in the Cascade Connection of Multiport Devices with Symmetric Feeding Lines
This paper is a postprint of a paper submitted to and accepted for publication in [journal] and is subject to Institution of Engineering and Technology Copyright. The copy of record is available at IET Digital LibraryThe traditional cascading of generalised scattering matrices (GSMs) assumes that the modal sets at the connected ports of a cascaded network are strictly equal. This implies a careful selection of the modal polarities, or the reference systems, of every port. Usually, the connection scheme of every device is known a priori. Then, the individual GSMs are pre-processed, or auxiliary devices, which correct possible modal mismatches at the ports, are included in appropriate positions among the cascade, so that the traditional cascading-by-pairs approach can be directly applied. This scheme clearly complicates the reutilisation of previously calculated GSMs, and mixes the cascading with the solution of the individual building blocks. In this study, a systematic procedure is proposed to define the polarity of the modes at the ports of a device fed with transmission lines or waveguides showing a single or double symmetry. The modified expressions to calculate the scattering parameters of the cascade of two multiport devices, incorporating the regular modal corrections to apply when this criterion is used to define the modal polarity at the ports, is also presented in this study. This strategy is more convenient from the point of view of programming, less error-prone and easier to implement.This work was supported by the Ministry of Science and Innovation, Spanish Government, under Research Projects TEC2013-47037-C05-3-R and TEC2013-47037-C05-1-R.Belenguer MartĂnez, Ă.; Borja, A.; DĂaz Caballero, E.; Esteban GonzĂĄlez, H.; Boria Esbert, VE. (2015). Systematic Procedure to Avoid Unintended Polarity Mismatch in the Cascade Connection of Multiport Devices with Symmetric Feeding Lines. IET Microwaves Antennas and Propagation. 9(11):1128-1135. https://doi.org/10.1049/iet-map.2014.0167S1128113591
A measurement of the CP asymmetry difference between Îc + â pK â K + and pÏâÏ+ decays
The difference between the CP asymmetries in the decays Î + c â pKâK+ and Î + c â pÏâÏ + is presented. Proton-proton collision data taken at centre-of-mass energies of 7 and 8 TeV collected by the LHCb detector in 2011 and 2012 are used, corresponding to an integrated luminosity of 3 fbâ1 . The Î + c candidates are reconstructed as part of the Î 0 b â Î + c ” âX decay chain. In order to maximize the cancellation of production and detection asymmetries in the difference, the final-state kinematic distributions of the two samples are aligned by applying phase-space-dependent weights to the Î + c â pÏâÏ + sample. This alters the definition of the integrated CP asymmetry to A wgt CP (pÏâÏ +). Both samples are corrected for reconstruction and selection efficiencies across the five-dimensional Î + c decay phase space. The difference in CP asymmetries is found to be âA wgt CP = ACP (pKâK+) â A wgt CP (pÏâÏ +) = (0.30 ± 0.91 ± 0.61) %, where the first uncertainty is statistical and the second is systemati
High infestation of invasive Aedes mosquitoes in used tires along the local transport network of Panama
Background: The longâdistance dispersal of the invasive disease vectors Aedes aegypti and Aedes albopictus has introâ duced arthropodâborne viruses into new geographical regions, causing a significant medical and economic burden. The usedâtire industry is an effective means of Aedes dispersal, yet studies to determine Aedes occurrence and the factors influencing their distribution along local transport networks are lacking. To assess infestation along the primary transport network of Panama we documented all existing garages that trade used tires on the highway and surveyed a subset for Ae. aegypti and Ae. albopictus. We also assess the ability of a mass spectrometry approach to classify mosâ quito eggs by comparing our findings to those based on traditional larval surveillance.
Results: Both Aedes species had a high infestation rate in garages trading used tires along the highways, providing a conduit for rapid dispersal across Panama. However, generalized linear models revealed that the presence of Ae. aegypti is associated with an increase in road density by a logâodds of 0.44 (0.73 ± 0.16; P = 0.002), while the presence of Ae. albopictus is associated with a decrease in road density by a logâodds of 0.36 (0.09 ± 0.63; P = 0.008). Identificaâ tion of mosquito eggs by mass spectrometry depicted similar occurrence patterns for both Aedes species as that obtained with traditional rearing methods.
Conclusions: Garages trading used tires along highways should be targeted for the surveillance and control of Aedesâmosquitoes and the diseases they transmit. The identification of mosquito eggs using mass spectrometry allows for the rapid evaluation of Aedes presence, affording time and cost advantages over traditional vector surveilâ lance; this is of importance for disease risk assessment.Background: The longâdistance dispersal of the invasive disease vectors Aedes aegypti and Aedes albopictus has introâ duced arthropodâborne viruses into new geographical regions, causing a significant medical and economic burden. The usedâtire industry is an effective means of Aedes dispersal, yet studies to determine Aedes occurrence and the factors influencing their distribution along local transport networks are lacking. To assess infestation along the primary transport network of Panama we documented all existing garages that trade used tires on the highway and surveyed a subset for Ae. aegypti and Ae. albopictus. We also assess the ability of a mass spectrometry approach to classify mosâ quito eggs by comparing our findings to those based on traditional larval surveillance.
Results: Both Aedes species had a high infestation rate in garages trading used tires along the highways, providing a conduit for rapid dispersal across Panama. However, generalized linear models revealed that the presence of Ae. aegypti is associated with an increase in road density by a logâodds of 0.44 (0.73 ± 0.16; P = 0.002), while the presence of Ae. albopictus is associated with a decrease in road density by a logâodds of 0.36 (0.09 ± 0.63; P = 0.008). Identificaâ tion of mosquito eggs by mass spectrometry depicted similar occurrence patterns for both Aedes species as that obtained with traditional rearing methods.
Conclusions: Garages trading used tires along highways should be targeted for the surveillance and control of Aedesâmosquitoes and the diseases they transmit. The identification of mosquito eggs using mass spectrometry allows for the rapid evaluation of Aedes presence, affording time and cost advantages over traditional vector surveilâ lance; this is of importance for disease risk assessment
Acute Loss of Cited2 Impairs Nanog Expression and Decreases Self-Renewal of Mouse Embryonic Stem Cells
Identifying novel players of the pluripotency gene regulatory network centered on Oct4, Sox2, and Nanog as well as delineating the interactions within the complex network is key to understanding self-renewal and early cell fate commitment of embryonic stem cells (ESC). While overexpression of the transcriptional regulator Cited2 sustains ESC pluripotency, its role in ESC functions remains unclear. Here, we show that Cited2 is important for proliferation, survival, and self-renewal of mouse ESC. We position Cited2 within the pluripotency gene regulatory network by defining Nanog, Tbx3, and Klf4 as its direct targets. We also demonstrate that the defects caused by Cited2 depletion are, at least in part, rescued by Nanog constitutive expression. Finally, we demonstrate that Cited2 is required for and enhances reprogramming of mouse embryonic fibroblasts to induced pluripotent stem cells.National Portuguese through FCT-Fundacao para a Ciencia e a Tecnologia [PEst-OE/EQB/LA0023/2013, PTDC/SAU-ENB/111702/2009]; Camara Municipal de Oeiras; Merck Sharp & Dhome Foundation-Portugal; CRUK; Leukaemia & Lymphoma Research; Kay Kendall Leukaemia Fund; Wellcome Trust; Medical Research Council; Cancer Research UK [12796, 14633]; Great Ormond Street Hospital Childrens Charity [W1062]; Medical Research Council [MC_U137973817, G1000801g, MC_qA137913
Search for beautiful tetraquarks in the Ï(1S)ÎŒ + ÎŒ â invariant-mass spectrum
Abstract: The ΄(1S)” +” â invariant-mass distribution is investigated for a possible exotic meson state composed of two b quarks and two b quarks, Xbbbb . The analysis is based on a data sample of pp collisions recorded with the LHCb detector at centre-of-mass energies â s = 7, 8 and 13 TeV, corresponding to an integrated luminosity of 6.3 fbâ1 . No significant excess is found, and upper limits are set on the product of the production cross-section and the branching fraction as functions of the mass of the Xbbbb state. The limits are set in the fiducial volume where all muons have pseudorapidity in the range [2.0, 5.0], and the Xbbbb state has rapidity in the range [2.0, 4.5] and transverse momentum less than 15 GeV/c. Keywords: B physics, Exotics, Hadron-Hadron scattering (experiments), Heavy quark productio
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