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Matrix formulation of fuzzy rule-based systems
In this paper, a matrix formulation of fuzzy rule based systems is introduced. A gradient descent training algorithm for the determination of the unknown parameters can also be expressed in a matrix form for various adaptive fuzzy networks. When converting a rule-based system to the proposed matrix formulation, only three sets of linear/nonlinear equations are required instead of set of rules and an inference mechanism. There are a number of advantages which the matrix formulation has compared with the linguistic approach. Firstly, it obviates the differences among the various architectures; and secondly, it is much easier to organize data in the implementation or simulation of the fuzzy system. The formulation will be illustrated by a number of examples
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A new approach to adaptive fuzzy control: the controller output error method
The controller output error method (COEM) is introduced and applied to the design of adaptive fuzzy control systems. The method employs a gradient descent algorithm to minimize a cost function which is based on the error at the controller output. This contrasts with more conventional methods which use the error at the plant output. The cost function is minimized by adapting some or all of the parameters of the fuzzy controller. The proposed adaptive fuzzy controller is applied to the adaptive control of a nonlinear plant and is shown to be capable of providing good overall system performance
Care, laboratory beagles and affective utopia
A caring approach to knowledge production has been portrayed as epistemologically radical, ethically vital and as fostering continuous responsibility between researchers and research-subjects. This article examines these arguments through focusing on the ambivalent role of care within the first large-scale experimental beagle colony, a self-professed âbeagle utopiaâ at the University of California, Davis, (1951-1986). We argue that care was at the core of the beagle colony; the lived environment was re-shaped in response to animals âspeaking backâ to researchers, and âloveâ and âkindnessâ were important considerations during staff recruitment. Ultimately, however, we show that care-relations were used to manufacture compliancy, preventing the predetermined ends of the experiment from being troubled. Rather than suggesting Davis would have been less ethically troubling, or more epistemologically radical, with âbetterâ care, however, we suggest the case troubles existing care theory and argue that greater attention needs to be paid to histories, contexts, and exclusions
Cross-correlation analysis to quantify relative spatial distributions of fat and protein in super-resolution microscopy images of dairy gels
The advent of super-resolution microscopy allows microstructures of foods to be explored in new depths, which when coupled with quantitative image analysis can provide a powerful analytical tool. Herein, a methodology is presented and applied to use a 2D spatial cross-correlation analysis to investigate the relative spatial arrangement of protein and fat in acid induced whole milk gels where the milk is either non-homogenised or has been homogenised at either 10 or 25âŻMPa. Two-channel images were taken using super-resolution Stimulated Emission Depletion (STED) microscopy and confocal microscopy. A term has been derived to extract the typical distance from the fat droplet surface and to the local maximum protein distribution. The fat droplet size is determined through 2D spatial autocorrelation analysis. Methods of analysis are applied to global images and to region specific analysis focussing on individual fat droplets. Cross-correlation analysis has been empirically validated using generated images with precise spatial features corresponding to the features of interest in true microscopy images, over appropriate length scales. The protein microstructure, fat droplet size and distances between the fat droplets and protein network are characterised. There are significantly different distances between the fat droplets and protein network in the homogenised samples compared to the non-homogenised sample. The extracted separation distances are below the diffraction limit of light, highlighting the utility of super-resolution imaging
Accurate masses and radii of normal stars: modern results and applications
This paper presents and discusses a critical compilation of accurate,
fundamental determinations of stellar masses and radii. We have identified 95
detached binary systems containing 190 stars (94 eclipsing systems, and alpha
Centauri) that satisfy our criterion that the mass and radius of both stars be
known to 3% or better. To these we add interstellar reddening, effective
temperature, metal abundance, rotational velocity and apsidal motion
determinations when available, and we compute a number of other physical
parameters, notably luminosity and distance. We discuss the use of this
information for testing models of stellar evolution. The amount and quality of
the data also allow us to analyse the tidal evolution of the systems in
considerable depth, testing prescriptions of rotational synchronisation and
orbital circularisation in greater detail than possible before. The new data
also enable us to derive empirical calibrations of M and R for single (post-)
main-sequence stars above 0.6 M(Sun). Simple, polynomial functions of T(eff),
log g and [Fe/H] yield M and R with errors of 6% and 3%, respectively.
Excellent agreement is found with independent determinations for host stars of
transiting extrasolar planets, and good agreement with determinations of M and
R from stellar models as constrained by trigonometric parallaxes and
spectroscopic values of T(eff) and [Fe/H]. Finally, we list a set of 23
interferometric binaries with masses known to better than 3%, but without
fundamental radius determinations (except alpha Aur). We discuss the prospects
for improving these and other stellar parameters in the near future.Comment: 56 pages including figures and tables. To appear in The Astronomy and
Astrophysics Review. Ascii versions of the tables will appear in the online
version of the articl
Primary culture of Rhodnius prolixus (Hemiptera: Reduviidae) salivary gland cells
In the present paper, we developed a primary culture of Rhodnius prolixus salivary gland and main salivary canal cells. Cells remained viable in culture for 30 days. Three types of cells were indentified in the salivary gland cultures, with binuclear cells being the most abundant. The supernatants of salivary cultures contained mainly 16-24 kDa proteins and presented anticoagulant and apyrase activities. Secretion vesicles were observed budding from the cellular monolayer of the main salivary canal cells. These results indicate that R. prolixus salivary proteins may be produced in vitro and suggest that the main salivary canal may have a possible secretory role
Antibody Labelling of Resilin in Energy Stores for Jumping in Plant Sucking Insects
The rubbery protein resilin appears to form an integral part of the energy storage structures that enable many insects to jump by using a catapult mechanism. In plant sucking bugs that jump (Hemiptera, Auchenorrhyncha), the energy generated by the slow contractions of huge thoracic jumping muscles is stored by bending composite bow-shaped parts of the internal thoracic skeleton. Sudden recoil of these bows powers the rapid and simultaneous movements of both hind legs that in turn propel a jump. Until now, identification of resilin at these storage sites has depended exclusively upon characteristics that may not be specific: its fluorescence when illuminated with specific wavelengths of ultraviolet (UV) light and extinction of that fluorescence at low pH. To consolidate identification we have labelled the cuticular structures involved with an antibody raised against a product of the Drosophila CG15920 gene. This encodes pro-resilin, the first exon of which was expressed in E. coli and used to raise the antibody. We show that in frozen sections from two species, the antibody labels precisely those parts of the metathoracic energy stores that fluoresce under UV illumination. The presence of resilin in these insects is thus now further supported by a molecular criterion that is immunohistochemically specific
Mechanical Metamaterials with Negative Compressibility Transitions
When tensioned, ordinary materials expand along the direction of the applied
force. Here, we explore network concepts to design metamaterials exhibiting
negative compressibility transitions, during which a material undergoes
contraction when tensioned (or expansion when pressured). Continuous
contraction of a material in the same direction of an applied tension, and in
response to this tension, is inherently unstable. The conceptually similar
effect we demonstrate can be achieved, however, through destabilisations of
(meta)stable equilibria of the constituents. These destabilisations give rise
to a stress-induced solid-solid phase transition associated with a twisted
hysteresis curve for the stress-strain relationship. The strain-driven
counterpart of negative compressibility transitions is a force amplification
phenomenon, where an increase in deformation induces a discontinuous increase
in response force. We suggest that the proposed materials could be useful for
the design of actuators, force amplifiers, micro-mechanical controls, and
protective devices.Comment: Supplementary information available at
http://www.nature.com/nmat/journal/v11/n7/abs/nmat3331.htm
Contribution of income and job strain to the association between education and cardiovascular disease in 1.6 million Danish employees
AIMS: We examined the extent to which associations between education and cardiovascular disease (CVD) morbidity and mortality are attributable to income and work stress. METHODS AND RESULTS: We included all employed Danish residents aged 30-59 years in 2000. Cardiovascular disease morbidity analyses included 1Â 638Â 270 individuals, free of cardiometabolic disease (CVD or diabetes). Mortality analyses included 41Â 944 individuals with cardiometabolic disease. We assessed education and income annually from population registers and work stress, defined as job strain, with a job-exposure matrix. Outcomes were ascertained until 2014 from health registers and risk was estimated using Cox regression. During 10Â 957Â 399 (men) and 10Â 776Â 516 person-years (women), we identified 51Â 585 and 24Â 075 incident CVD cases, respectively. For men with low education, risk of CVD was 1.62 [95% confidence interval (CI) 1.58-1.66] before and 1.46 (95% CI 1.42-1.50) after adjustment for income and job strain (25% reduction). In women, estimates were 1.66 (95% CI 1.61-1.72) and 1.53 (95% CI 1.47-1.58) (21% reduction). Of individuals with cardiometabolic disease, 1736 men (362Â 234 person-years) and 341 women (179Â 402 person-years) died from CVD. Education predicted CVD mortality in both sexes. Estimates were reduced with 54% (men) and 33% (women) after adjustment for income and job strain. CONCLUSION: Low education predicted incident CVD in initially healthy individuals and CVD mortality in individuals with prevalent cardiometabolic disease. In men with cardiometabolic disease, income and job strain explained half of the higher CVD mortality in the low education group. In healthy men and in women regardless of cardiometabolic disease, these factors explained 21-33% of the higher CVD morbidity and mortality
Tuning ultrafast electron thermalization pathways in a van der Waals heterostructure
Ultrafast electron thermalization - the process leading to Auger
recombination, carrier multiplication via impact ionization and hot carrier
luminescence - occurs when optically excited electrons in a material undergo
rapid electron-electron scattering to redistribute excess energy and reach
electronic thermal equilibrium. Due to extremely short time and length scales,
the measurement and manipulation of electron thermalization in nanoscale
devices remains challenging even with the most advanced ultrafast laser
techniques. Here, we overcome this challenge by leveraging the atomic thinness
of two-dimensional van der Waals (vdW) materials in order to introduce a highly
tunable electron transfer pathway that directly competes with electron
thermalization. We realize this scheme in a graphene-boron nitride-graphene
(G-BN-G) vdW heterostructure, through which optically excited carriers are
transported from one graphene layer to the other. By applying an interlayer
bias voltage or varying the excitation photon energy, interlayer carrier
transport can be controlled to occur faster or slower than the intralayer
scattering events, thus effectively tuning the electron thermalization pathways
in graphene. Our findings, which demonstrate a novel means to probe and
directly modulate electron energy transport in nanoscale materials, represent
an important step toward designing and implementing novel optoelectronic and
energy-harvesting devices with tailored microscopic properties.Comment: Accepted to Nature Physic
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