We report on an all-sky search for continuous gravitational waves in the frequency band 20–2000 Hz and with a frequency time derivative in the range of [−1.0,+0.1]×10−8 Hz/s. Such a signal could be produced by ...
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We report on an all-sky search for continuous gravitational waves in the frequency band 20–2000 Hz and with a frequency time derivative in the range of [−1.0,+0.1]×10−8 Hz/s. Such a signal could be produced by a nearby, spinning and slightly nonaxisymmetric isolated neutron star in our Galaxy. This search uses the LIGO data from the first six months of Advanced LIGO’s and Advanced Virgo’s third observational run, O3. No periodic gravitational wave signals are observed, and 95% confidence-level (C.L.) frequentist upper limits are placed on their strengths. The lowest upper limits on worst-case (linearly polarized) strain amplitude h0 are ∼1.7×10−25 near 200 Hz. For a circularly polarized source (most favorable orientation), the lowest upper limits are ∼6.3×10−26. These strict frequentist upper limits refer to all sky locations and the entire range of frequency derivative values. For a population-averaged ensemble of sky locations and stellar orientations, the lowest 95% C.L. upper limits on the strain amplitude are ∼1.4×10−25. These upper limits improve upon our previously published all-sky results, with the greatest improvement (factor of ∼2) seen at higher frequencies, in part because quantum squeezing has dramatically improved the detector noise level relative to the second observational run, O2. These limits are the most constraining to date over most of the parameter space searched.
Business sustainability integration is a complex task and strongly linked to operations management. The challenge is to conduct more sustainable operations through companies? value chain and their network. In sustaina...
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Business sustainability integration is a complex task and strongly linked to operations management. The challenge is to conduct more sustainable operations through companies? value chain and their network. In sustainable operations management area, maturity models have been developed for specific purposes. However, there is a lack of models that considers sustainability integration through the evolution of sustainable operations? capabilities. Based on literature review, case studies and expert panels, this paper develops and proposes a maturity framework defined by sustainable operations management theory. Its is possible to identify an evolutionary path, which goes from an initial approach focused in compliance aspects and firm?s value protection to an innovative approach, based on corporate social responsibility supporting operations? integration in a sustainable system, and long-term values development. The experts? panel identified key processes areas that need to be prioritized in each level, and also analyzed the adaptation of some elements from Capability Maturity Model Integration (CMMI) to sustainable maturity framework design and development.
CFRP which consists of carbon fiber/phenol resin is widely used for a thermal protection system in Aerospace field. Rapid-heating-induced thermal deformation of CFRP is measured using digital image correlation (DIC) t...
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Automobile drivers and passengers feel tactile emotions from surface texture of in-vehicle materials, and it affects satisfaction of automobile users. Prior studies have examined a variety of emotional dimensions, inc...
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In the search for renewable energy sources, solar energy appears, among others, as a powerful alternative;mainly for those countries located at Earth’s equatorial region. This is the case of a Fresnel device that use...
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In the search for renewable energy sources, solar energy appears, among others, as a powerful alternative;mainly for those countries located at Earth’s equatorial region. This is the case of a Fresnel device that uses solar radiation to warm-up the air;for instance, within saunas. Authors coined the term sustainable technological innovation to refer to a technological innovation in accordance to the principles of sustainability. The object of this research was comparing the sustainability of a Fresnel Lens Solar Concentration (FLSC) against the sustainability of other twelve alternatives to generate heat. This article assesses the sustainability of fourteen technological options for heat generation and transfer to saunas in the northwest region of Mexico where temperatures often reach above 45 C and where there is a greater potential for exploiting solar energy. Emergy accounting, economic analysis, and global warming potential are the three indicators considered in quantifying sustainability. Results show that infrared ceramic photovoltaic, infrared carbon photovoltaic and infrared metal photovoltaic are the most sustainable systems. The Fresnel device reached the fourth and tenth position, using electricity from photovoltaic and from grid respectively, among all fourteen assessed devices, respectively. Although Fresnel equipment does not release any global warming gases into the atmosphere, or even it demands low amount of non-renewable resources, 1.40 and 4.47 E17 seJF/yr. it requires high economic investment, 20,800 and 79,600 USD/yr, for the implementation and operation phases, which decrease its sustainability performance compared to twelve other evaluated devices.
The lens of exergy is used to investigate a wingtip vortex in the near wake over a range of angles of attack. Exergy is the measure of thermodynamically "available" energy as determined through the more disc...
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Several thousand core-collapse supernovae (CCSNe) of different flavors have been discovered so far. However, identifying their progenitors has remained an outstanding open question in astrophysics. Studies of SN host ...
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This paper presents a procedure for input selection and parameter estimation for system identification based on Radial Basis Functions Neural Networks (RBFNNs) models and Free Search Differential Evolution (FSDE). We ...
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There is a growing demand for polymeric composite materials, mainly, in industrial applications. For instance, bipolar plates for polymer electrolyte fuel cell in automobile applications. This kind of composite can re...
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