126 research outputs found
What May Visualization Processes Optimize?
In this paper, we present an abstract model of visualization and inference
processes and describe an information-theoretic measure for optimizing such
processes. In order to obtain such an abstraction, we first examined six
classes of workflows in data analysis and visualization, and identified four
levels of typical visualization components, namely disseminative,
observational, analytical and model-developmental visualization. We noticed a
common phenomenon at different levels of visualization, that is, the
transformation of data spaces (referred to as alphabets) usually corresponds to
the reduction of maximal entropy along a workflow. Based on this observation,
we establish an information-theoretic measure of cost-benefit ratio that may be
used as a cost function for optimizing a data visualization process. To
demonstrate the validity of this measure, we examined a number of successful
visualization processes in the literature, and showed that the
information-theoretic measure can mathematically explain the advantages of such
processes over possible alternatives.Comment: 10 page
Golan)
Abstract A new data-based method of estimation and variable selection in linear statistical models is proposed. This method is based on a generalized maximum entropy formalism, and makes use of both sample and non-sample information in determining a basis for coe$cient shrinkage and extraneous variable identi"cation. In contrast to tradition, shrinkage and variable selection are achieved on a coordinate-by-coordinate basis, and the procedure works well for both ill-and well-posed statistical models. Analytical asymptotic results are presented and sampling experiments are used as a basis for determining "nite sample behavior and comparing the sampling performance of the new estimation rule with traditional competitors. Solution algorithms for the non-linear inversion problem that results are simple to implement. 2001 Elsevier Science S.A. All rights reserved. JEL classixcation: C13; C14; C
The Use of Critical Solution Mixtures for Contaminated Sediments Remediation
Using a critical solution mixture, into which chelating agents have been dissolved, resulted in the efficient, rapid and simultaneous removal of both heavy metals and organic pollutants from contaminated sediments. Both heating and cooling across the immiscibility curve and isothermal extraction were investigated. In addition, the extraction yields were compared to those obtained with solution mixtures that do not possess a critical point of miscibility. Extraction yields of the former were superior to those of the latter in the range of relevant pressures (1 atm.) and temperatures. Extraction via heating and cooling across the miscibility curve resulted in the removal of close to 90% of the heavy metals and practically all of the organic contaminants, compared to only about 40% when the extraction was performed isothermally at around 20oC
Designing wearable technologies for spatial awareness and social interactions
Thesis: S.M., Massachusetts Institute of Technology, School of Architecture and Planning, Program in Media Arts and Sciences, 2018.Cataloged from PDF version of thesis.Includes bibliographical references (pages 93-96).We live in an era of constant connectedness; we carry a smartphone in our pocket, headsets on our ears and enjoy limitless and regular access to almost any content we wish. However, the use of the personal computing devices that allow this connection with the virtual world damages our ability to connect with the physical world surrounding us; our eyes are focused on screens, our ears are covered by headphones and our attention jumps between apps. As a result, many of us are actually finding it harder to have face to face interactions with others than ever before. We are getting worse at communicating with the people around us, in the present, and tend to prefer virtual alternatives, as they are easier to operate, less stressful and fully under our control. This thesis proposes a perspective at wearable and personal computing devices and the role that their design may play in creating and fighting the epidemic of growing isolation. We hypothesize that the negative social trends that we witness as a result of using smartphones, headphones and other personal devices are not the purpose of these technologies, but rather an unwanted byproduct of their use. We propose to redesign ubiquitous personal technologies to reduce their isolating effect and use them to foster more physical interpersonal interactions and spatial awareness, by equipping them with additional modes of operation that force interpersonal interaction. We call this family of new interfaces IceBreakware. As a proof of concept, we present LeakyPhones, an instance of IceBreakware and a social version of the ubiquitous headphones. LeakyPhones is an interface that allows colocated and real time audio sharing between two or more people by coupling music sharing with a gaze. LeakyPhones encourages users to explore their surroundings with their eyes, and interact with the people around them. They also change the meaning of a previously private medium such as the headphones and turn it into public at will. By doing this, Leakyphones tries to overcome some of the limitations of normal headphones. This work explores corrective measures to standard personal devices that can possibly be implemented to existing technologies in order to encourage desired social behaviors. It demonstrates how gaze and music sharing may act as a social vehicle and help and encourage positive real-world interactions between people while not substituting them with virtual alternatives.by Amos Golan.S.M
Listeria monocytogenes Infection in Israel and Review of Cases Worldwide
Listeria monocytogenes, an uncommon foodborne pathogen, is increasingly recognized as a cause of life-threatening disease. A marked increase in reported cases of listeriosis during 1998 motivated a retrospective nationwide survey of the infection in Israel. From 1995 to 1999, 161 cases were identified; 70 (43%) were perinatal infections, with a fetal mortality rate of 45%. Most (74%) of the 91 nonperinatal infections involved immunocompromised patients with malignancies, chronic liver disease, chronic renal failure, or diabetes mellitus. The common clinical syndromes in these patients were primary bacteremia (47%) and meningitis (28%). The crude case-fatality rate in this group was 38%, with a higher death rate in immunocompromised patients
Revisiting the Gaia Hypothesis: Maximum Entropy, Kauffman’s ‘Fourth Law’ and Physiosemeiosis
Recently, Kleidon suggested to analyze Gaia as a non-equilibrium
thermodynamic system that continuously moves away from equilibrium, driven by
maximum entropy production which materializes in hierarchically coupled
mechanisms of energetic flows via dissipation and physical work. I relate this
view with Kauffman's 'Fourth Law of Thermodynamics', which I interprete as a
proposition about the accumulation of information in evolutionary processes.
The concept of physical work is expanded to including work directed at the
capacity to work: I offer a twofold specification of Kauffman's concept of an
'autonomous agent', one as a 'self-referential heat engine', and the other in
terms of physiosemeiosis, which is a naturalized application of Peirce's theory
of signs. The conjunction of these three theoretical sources, Maximum Entropy,
Kauffman's Fourth Law, and physiosemeiosis, shows that the Kleidon restatement
of the Gaia hypothesis is equivalent to the proposition that the biosphere is
generating, processing and storing information, thus directly treating
information as a physical phenomenon. There is a fundamental ontological
continuity between the biological processes and the human economy, as both are
seen as information processing and entropy producing systems. Knowledge and
energy are not substitutes, with energy and information being two aspects of
the same underlying physical process
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