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Three transiting exoplanet candidate stars were discovered in a ground-based photometric survey prior to the launch of NASA's Kepler mission. Kepler observations of them were obtained during Quarter 1 of the Kepler mission. All three stars are faint by radial velocity follow-up standards, so we have examined these candidates with regard to eliminating false positives and providing high confidence exoplanet selection.We present a first attempt to exclude false positives for this set of faint stars without high-resolution radial velocity analysis. This method of exoplanet confirmation will form a large part of the Kepler mission follow-up for Jupiter-sized exoplanet candidates orbiting faint stars. Using the Kepler light curves and pixel data, as well as medium-resolution reconnaissance spectroscopy and speckle imaging, we find that two of our candidates are binary stars. One consists of a late-F star with an early M companion, while the other is a K0 star plus a late M-dwarf/brown dwarf in a 19 day elliptical orbit. The third candidate (BOKS-1) is an r = 15 G8V star hosting a newly discovered exoplanet with a radius of 1.12 RJupiter in a 3.9 day orbit. © 2010 The American Astronomical Society. All rights reserved.
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Pores are naturally occurring entities in bone. Changes in pore size and number are often associated with diseases such as Osteoporosis and even microgravity during spaceflight. Studying bone perforations may yield great insight into bone's material properties, including bone density and may contribute to identifying therapies to halt or potentially reverse bone loss. Current technologies used in this field include nuclear magnetic resonance, micro-computed tomography and the field emission scanning electron microscope (FE-SEM) 2, 5. However, limitations in each method limit further advancement. The objective of this study was to assess the effectiveness of using a new generation of analytical instruments, the TM-1000 tabletop, SEM with back-scatter electron (BSE) detector, to analyze cortical bone porosities. Hind limb unloaded and age-based controlled mouse femurs were extracted and tested in vitro for changes in pores on the periosteal surface. An important advantage of using the tabletop is the simplified sample preparation that excludes extra coatings, dehydration and fixation steps that are otherwise required for conventional SEM. For quantitative data, pores were treated as particles in order to use an analyze particles feature in the NIH ImageJ software. Several image-processing techniques for background smoothing, thresholding and filtering were employed to produce a binary image suitable for particle analysis. It was hypothesized that the unloaded bones would show an increase in pore area, as the lack of mechanical loading would affect bone-remodeling processes taking place in and around pores. Preliminary results suggest only a slight different in frequency but not in size of pores between unloaded and control femurs.
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The Kepler mission was designed to determine the frequency of Earth-sized planets in and near the habitable zone of Sun-like stars. The habitable zone is the region where planetary temperatures are suitable for water to exist on a planet's surface. During the first 6 weeks of observations, Kepler monitored 156,000 stars, and five new exoplanets with sizes between 0.37 and 1.6 Jupiter radii and orbital periods from 3.2 to 4.9 days were discovered. The density of the Neptune-sized Kepler-4b is similar to that of Neptune and GJ 436b, even though the irradiation level is 800,000 times higher. Kepler-7b is one of the lowest-density planets (∼0.17 gram per cubic centimeter) yet detected. Kepler-5b, -6b, and -8b confirm the existence of planets with densities lower than those predicted for gas giant planets.
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We have developed an assessment of students' ability to solve standard textbook style problems and are currently engaged in the validation and revision process. The assessment covers the topics of force and motion, conservation of momentum and conservation of energy at a level consistent with most calculus-based, introductory physics courses. This tool is discussed in more detail in an accompanying paper by Marx and Cummings. [1] Here we present preliminary beta-test data collected at four schools during the 2009/2010 academic year. Data include both pre- and post-instruction results for introductory physics courses as well as results for physics majors in later years. In addition, we present evidence that right/wrong grading may well be a perfectly acceptable grading procedure for a course-level assessment of this type. © 2010 American Institute of Physics.
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We employ focused ion beam patterning of single crystal Si(100) surfaces to template the assembly of Ge(Si) nanostructure arrays. The evolution and final structures of the templated arrays are determined by combinations of transmission electron, low energy electron microscope, focused ion beam and scanning probe microscopies. It is shown how the positions of individual nanostructures may be controlled to the order of 10 nm. However, to achieve controlled spacings between elements that are in the 10 nm range requires careful matching of the characteristic lengths scales of self assembly mechanisms to the length scales of the external lithographic "forcing functions". © 2010 IOP Publishing Ltd.
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In this paper we discuss the early stages of development of a survey instrument to assess students' problem-solving abilities in a first-term, undergraduate, calculus-based physics course. Specifically, we present our motivation for the development of such a survey, details of a preliminary version of the survey, and some sample items. © 2010 American Institute of Physics.
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The purpose of this study was to compare the ability of several texture analysis parameters to differentiate textured samples from a smooth control on images obtained with an Atomic Force Microscope (AFM). Surface roughness plays a major role in the realm of material science, especially in integrated electronic devices. As these devices become smaller and smaller, new materials with better electrical properties are needed. New materials with smoother surface morphology have been found to have superior electrical properties than their rougher counterparts. Therefore, in many cases surface texture is indicative of the electrical properties that material will have. Physical vapor deposition techniques such as Jet Vapor Deposition and Molecular Beam Epitaxy are being utilized to synthesize these materials as they have been found to create pure and uniform thin layers. For the current study, growth parameters were varied to produce a spectrum of textured samples. The focus of this study was the image processing techniques associated with quantifying surface texture. As a result of the limited sample size, there was no attempt to draw conclusions about specimen processing methods. The samples were imaged using an AFM in tapping mode. In the process of collecting images, it was discovered that roughness data was much better depicted in the microscope's "height" mode as opposed to "equal area" mode. The AFM quantified the surface texture of each image by returning RMS roughness and the first order histogram statistics of mean roughness, standard deviation, skewness, and kurtosis. Color images from the AFM were then processed on an off line computer running NIH ImageJ with an image texture plug in. This plug in produced another set of first order statistics computed from each images' histogram as well as second order statistics computed from each images' cooccurrence matrix. The second order statistics, which were originally proposed by Haralick, include contrast, angular second moment, correlation, inverse difference moment, and entropy. These features were computed in the 0°, 45°, 90°, and 135° directions. The findings of this study propose that the best combination of quantitative texture parameters is standard deviation, 0° inverse difference moment, and 0° entropy, all of which are obtained from the NIH ImageJ texture plug in. © 2010 Copyright SPIE - The International Society for Optical Engineering.
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Valence electron energy-loss spectroscopy is used to investigate the plasmon excitations of ultrathin SrTiO3 sandwiched between amorphous Si and crystalline Si. Two plasmon excitations were observed, one at 15.8 eV and the other at 28.7 eV. Our calculations, based on dielectric-function theory, suggest that the former peak originates from the coupling of the Si layers and is related to the geometry of the structure, and the latter peak results from the SrTiO3 bulk plasmon after a redshift. Our findings demonstrate the value of valence electron energy-loss spectroscopy in detecting a local change in the effective electron mass. © 2010 American Institute of Physics.
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A method has been developed to use the finite escape depth of the photoelectrons emitted in ultraviolet photoemission spectroscopy (UPS) to determine the electronic density-of-states at the interface between two dissimilar metal oxides. Ultrathin films of one oxide are grown heteroepitaxially, one monolayer at a time, on a single-crystal substrate of the other oxide, and UPS spectra are taken after each complete monolayer. By comparing experimental UPS spectra with calculated spectra based on specific models of the interfacial structure, the interfacial density-of-states can be extracted. The two oxide systems studied here are NiO-Fe 3O 4 and CoO-Fe 3O 4. The former system is found to have an atomically abrupt interface, with no significant density of interface states. For CoO, however, an interfacial electronic spectrum, different from that of either the substrate or the overlayer, is found. The spatial extent and possible origin of those interfacial states is discussed. © 2010 WILEY-VCH Verlag GmbH &. Co. KGaA, Weinheim.
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Purpose – The paper aims to examine the nature of computer ethics as a field of study in light of 20 years of Ethicomp, arguing that computer ethics beyond mere compliance will have to be pluralistic and sensitive to the starting places of various audiences. Design/methodology/approach – The essay offers a philosophical rather than empirical analysis, but the ideal of open inquiry is observed to be manifest in the practice of Ethicomp. Findings – If computer ethics is to constitute a real engagement with industry and society that cultivates a genuine sensitivity to ethical concerns in the creation, development and implementation of technologies, a genuine sensitivity that stands in marked contrast to ethics as “mere compliance”, then computer ethics will have to persist in issuing an open invitation to inquiry. Originality/value – The celebration of 20 years of Ethicomp is an occasion to reflect on who we are and what we mean to be doing. Inclusive of previous accounts (e.g. Moor and Gotterbarn), while going beyond them, an inquiry-based conception of computer ethics makes room for all the various dimensions of computer ethics. ©Emerald Group Publishing Limited
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Given the context of the Physics just explored, it will not be a surprise if time (chrόnos) in Aristotle’s analytic of time turns out to be not a being qua itself but an attribute of motion, an interval.
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The key to taking in Aristotle’s treatise on time is to approach it with the understanding that Aristotle was not a philosopher concerned with time —in questions about time or in delimiting the being of time.
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I defend social media's potential to support Aristotelian virtue friendship against a variety of objections. I begin with Aristotle's claim that the foundation of the best friendships is a shared life. Friends share the distinctively human and valuable components of their lives, especially reasoning together by sharing conversation and thoughts, and communal engagement in valued activities. Although some have charged that shared living is not possible between friends who interact through digital social media, I argue that social media preserves the relevantly human and valuable portions of life, especially reasoning, play, and exchange of ideas. I then consider several criticisms of social media's potential to host friendships, and refute or weaken the force of these objections, using this conception of a distinctively human shared life. I conclude that we should use the shared life to evaluate features of social media and norms for users' conduct.
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In The Philosophy of Information, Luciano Floridi presents an ontological theory of Being qua Being, which he calls "Informational Structural Realism", a theory which applies, he says, to every possible world. He identifies primordial information ("dedomena") as the foundation of any structure in any possible world. The present essay examines Floridi's defense of that theory, as well as his refutation of "Digital Ontology" (which some people might confuse with his own). Then, using Floridi's ontology as a starting point, the present essay adds quantum features to dedomena, yielding an ontological theory for our own universe, Quantum Informational Structural Realism, which provides a metaphysical interpretation of key quantum phenomena, and diminishes the "weirdness" or "spookiness" of quantum mechanics. © 2013 The Author(s).
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Zhuangzi suggests that death is a transformation that we commonly and mistakenly think means the end of someone but really just marks a new phase of existence. This metaphysical thesis is presented at several points in the text as an explanation of distinctively Daoist responses to death and loss. Some (such as Wong 2006) take a Daoist response to death, as presented by Zhuangzi, to indicate dual perspectives on friendship and death. But I argue that the metaphysical view sketched above is consistent with a unified perspective, allowing the Daoist to enjoy deep friendships without risking some potential for grief typically associated with strong attachment. However, it leaves the Daoist best suited to friendships with those who endorse the same metaphysics. Furthermore, while the grief associated with the death of a friend is somewhat mitigated, the Daoist has reason to mourn even given this thesis. © 2014 The University of Memphis.
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This is a translation of the second chapter of F.W.J. Schelling's Abhandlungen zur Erlaüterung des Idealismus der Wissenschaftslehre (1796-1797). It is preceded by a brief introduction in which I situate the chapter within Schelling's oeuvre and suggest that it is not only an early articulation of Schellingian Naturphilosophie, but also prescient, anticipating Schelling's later positive philosophy. © W. S. Maney & Son Ltd 2014.
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Business ethics education is experiencing a renaissance as recurring corporate scandals and malpractice over the last decade have ensured that most universities now see the subject as an important and necessary component of any business degree course. As well as integrating professional ethics into their curriculum, Business Schools are also developing standalone ethics courses, showing that they take seriously their responsibility to help prepare the next generation of managers to improve business' track record of transparency, accountability and sustainable development. However what are the learning approaches that will help to bring about real improvements in business ethics learning at university? This paper argues that a holistic approach to ethics teaching is needed, in which students are encouraged to develop ethical knowledge and skills within their personal value systems. In this way ethics does not become something apart but integrated into one's terms of reference. The paper discusses a particular pedagogic approach designed to develop a student's 'critical consciousness' using a student-led learning method in which students actively engage with important concepts and discuss the issues amongst themselves within an environment where they can speak freely. Qualitative interviews with a selection of undergraduates on the compulsory first year professional ethics module provide insight into the impact of the method on attitudes and behaviours. © 2013 Elsevier Ltd.
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This brief article describes the circumstances that led to the creation of the journal Metaphilosophy in autumn 1968. A year after I had left graduate school, an unfortunate accident left me flat on my back for several weeks with nothing to do while recuperating from eye surgery. Bored, I decided to do something constructive, so I created a scholarly journal devoted to articles about the nature of philosophy, or how the different schools or branches of philosophy relate to each other, or how philosophy relates to other disciplines. I made up the word "metaphilosophy" to describe such content, and I decided to call the journal by that name. With help from my wife, from my best friend, and from my undergraduate philosophy mentor, the journal Metaphilosophy was launched. © 2011 Metaphilosophy LLC and Blackwell Publishing Ltd.
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Individuals who become ill as a result of personal lifestyle choices often shift the monetary costs of their healthcare needs to the taxpaying public or to fellow members of a private insurance pool. Some argue that policies permitting such cost shifting are unfair. Arguments for this view may seem to draw support from luck egalitarian accounts of distributive justice. This essay argues that the luck egalitarian framework provides no such support. To allocate healthcare costs on the basis of personal responsibility would arbitrarily and publicly burden socially detectable risk-takers while undetectable risk-takers continue to get a free ride. That problem is unavoidable even on the assumption that distributive institutions outside the healthcare sector are fully just. In actual, farfrom-just societies, imposing personal liability for the costs of voluntary risk taking would be wrong for an additional reason. Doing so would tend to magnify existing distributive injustices. These conclusions draw attention to two common 'moral fallacies of the second best' that can arise when applying ideal normative theory to matters of institutional design and in real-world policy contexts. © 2011 Springer Science+Business Media B.V.
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