WorldWideScience

Sample records for solves solar paradox

  1. ASA's Chandra Neon Discovery Solves Solar Paradox

    Science.gov (United States)

    2005-07-01

    NASA's Chandra X-ray Observatory survey of nearby sun-like stars suggests there is nearly three times more neon in the sun and local universe than previously believed. If true, this would solve a critical problem with understanding how the sun works. "We use the sun to test how well we understand stars and, to some extent, the rest of the universe," said Jeremy Drake of the Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass. "But in order to understand the sun, we need to know exactly what it is made of," he added. It is not well known how much neon the sun contains. This is critical information for creating theoretical models of the sun. Neon atoms, along with carbon, oxygen and nitrogen, play an important role in how quickly energy flows from nuclear reactions in the sun's core to its edge, where it then radiates into space. Chandra X-ray Spectrum of II Pegasi Chandra X-ray Spectrum of II Pegasi The rate of this energy flow determines the location and size of a crucial stellar region called the convection zone. The zone extends from near the sun's surface inward approximately 125,000 miles. The zone is where the gas undergoes a rolling, convective motion much like the unstable air in a thunderstorm. "This turbulent gas has an extremely important job, because nearly all of the energy emitted at the surface of the sun is transported there by convection," Drake said. The accepted amount of neon in the sun has led to a paradox. The predicted location and size of the solar convection zone disagree with those deduced from solar oscillations. Solar oscillations is a technique astronomers previously relied on to probe the sun's interior. Several scientists have noted the problem could be fixed if the abundance of neon is in fact about three times larger than currently accepted. Attempts to measure the precise amount of neon in the Sun have been frustrated by a quirk of nature; neon atoms in the Sun give off no signatures in visible light. However, in a gas

  2. Privacy Awareness: A Means to Solve the Privacy Paradox?

    Science.gov (United States)

    Pötzsch, Stefanie

    People are limited in their resources, i.e. they have limited memory capabilities, cannot pay attention to too many things at the same time, and forget much information after a while; computers do not suffer from these limitations. Thus, revealing personal data in electronic communication environments and being completely unaware of the impact of privacy might cause a lot of privacy issues later. Even if people are privacy aware in general, the so-called privacy paradox shows that they do not behave according to their stated attitudes. This paper discusses explanations for the existing dichotomy between the intentions of people towards disclosure of personal data and their behaviour. We present requirements on tools for privacy-awareness support in order to counteract the privacy paradox.

  3. Patient autonomy in chronic care: solving a paradox

    Directory of Open Access Journals (Sweden)

    Reach G

    2013-12-01

    Full Text Available Gérard Reach Department of Endocrinology, Diabetes, and Metabolic Diseases, Avicenne Hospital AP-HP, and EA 3412, CRNH-IdF, Paris 13 University, Sorbonne Paris Cité, Bobigny, France Abstract: The application of the principle of autonomy, which is considered a cornerstone of contemporary bioethics, is sometimes in obvious contradiction with the principle of beneficence. Indeed, it may happen in chronic care that the preferences of the health care provider (HCP, who is largely focused on the prevention of long term complications of diseases, differ from those, more present oriented, preferences of the patient. The aims of this narrative review are as follows: 1 to show that the exercise of autonomy by the patient is not always possible; 2 where the latter is not possible, to examine how, in the context of the autonomy principle, someone (a HCP can decide what is good (a treatment for someone else (a patient without falling into paternalism. Actually this analysis leads to a paradox: not only is the principle of beneficence sometimes conflicting with the principle of autonomy, but physician's beneficence may enter into conflict with the mere respect of the patient; and 3 to propose a solution to this paradox by revisiting the very concepts of the autonomous person, patient education, and trust in the patient–physician relationship: this article provides an ethical definition of patient education. Keywords: preference, autonomy, person, reflexivity, empathy, sympathy, patient education, trust, respect, care

  4. Lethal mutants and truncated selection together solve a paradox of the origin of life.

    Directory of Open Access Journals (Sweden)

    David B Saakian

    Full Text Available BACKGROUND: Many attempts have been made to describe the origin of life, one of which is Eigen's cycle of autocatalytic reactions [Eigen M (1971 Naturwissenschaften 58, 465-523], in which primordial life molecules are replicated with limited accuracy through autocatalytic reactions. For successful evolution, the information carrier (either RNA or DNA or their precursor must be transmitted to the next generation with a minimal number of misprints. In Eigen's theory, the maximum chain length that could be maintained is restricted to 100-1000 nucleotides, while for the most primitive genome the length is around 7000-20,000. This is the famous error catastrophe paradox. How to solve this puzzle is an interesting and important problem in the theory of the origin of life. METHODOLOGY/PRINCIPAL FINDINGS: We use methods of statistical physics to solve this paradox by carefully analyzing the implications of neutral and lethal mutants, and truncated selection (i.e., when fitness is zero after a certain Hamming distance from the master sequence for the critical chain length. While neutral mutants play an important role in evolution, they do not provide a solution to the paradox. We have found that lethal mutants and truncated selection together can solve the error catastrophe paradox. There is a principal difference between prebiotic molecule self-replication and proto-cell self-replication stages in the origin of life. CONCLUSIONS/SIGNIFICANCE: We have applied methods of statistical physics to make an important breakthrough in the molecular theory of the origin of life. Our results will inspire further studies on the molecular theory of the origin of life and biological evolution.

  5. Solving Strategic Paradoxes through Organizational Ambidexterity - A Foray into the Literature -

    Directory of Open Access Journals (Sweden)

    Ogrean Claudia

    2016-08-01

    Full Text Available In a world of unprecedented (diachronic and synchronic complexities like ours, firms are forced to deal with an increasing number of organizational paradoxes that challenge their strategic choices. Under these circumstances, ambidexterity could become a (dynamic core competence for firms, making the ambidextrous organization an imperative for businesses more than ever before. The paper aims to explore, based on an integrative approach, the most relevant literature on the interdependencies between the two topics (strategic paradoxes and organizational ambidexterity, in order to identify the most important thesis, arguments and solutions that support the ambidextrous organization, four decades after its first introduction into the academic literature (Duncan, 1976.

  6. Primary Evaporites for the Messinian Salinity Crisis: the shallow gypsum vs. deep dolomite formation paradox solved

    Science.gov (United States)

    De Lange, Gert J.; Krijgsman, Wout

    2014-05-01

    The Messinian Salinity Crisis (MSC) is a dramatic event that took place ~ 5.9 Ma ago, and resulted in the deposition of 0.3-3 km thick evaporites at the Mediterranean seafloor. A considerable and long-lasting controversy existed on the modes of their formation. During the CIESM Almeria Workshop a consensus was reached on several aspects. In addition, remaining issues to be solved were identified, such as for the observed shallow gypsum versus deep dolostone deposits for the early phase of MSC. The onset of MSC is marked by deposition of gypsum/sapropel-like alternations, thought to relate to arid/humid climate conditions. Gypsum precipitation only occurred at marginal settings, while dolomite containing rocks have been reported from deeper settings. A range of potential explanations have been reported, most of which cannot satisfactorily explain all observations. Biogeochemical processes during MSC are poorly understood and commonly neglected. These may, however, explain that different deposits formed in shallow versus deep environments without needing exceptional physical boundary conditions for each. We present here a unifying mechanism in which gypsum formation occurs at all shallow water depths but its preservation is mostly limited to shallow sedimentary settings. In contrast, ongoing anoxic organic matter (OM) degradation processes in the deep basin result in the formation of dolomite. Gypsum precipitation in evaporating seawater takes place at 3-7 times concentrated seawater; seawater is always largely oversaturated relative to dolomite but its formation is thought to be inhibited by the presence of dissolved sulphate. Thus the conditions for formation of gypsum exclude those for the formation of dolomite and vice versa. Another process that links the saturation states of gypsum and dolomite is that of OM degradation by sulphate reduction. In stagnant deep water, oxygen is rapidly depleted through OM degradation, then sulphate becomes the main oxidant for OM

  7. Geological Sulfur Isotopes Indicate Elevated OCS in the Archean Atmosphere, Solving the Faint Young Sun Paradox

    DEFF Research Database (Denmark)

    Ueno, Yuichiro; Johnson, Matthew Stanley; Danielache, Sebastian Oscar

    2009-01-01

    Distributions of sulfur isotopes in geological samples would provide a record of atmospheric composition if the mechanism producing the isotope effects could be described quantitatively. We determined the UV absorption spectra of 32SO2, 33SO2, and 34SO2 and use them to interpret the geological re......-rich, reducing Archean atmosphere. The radiative forcing, due to this level of OCS, is able to resolve the faint young sun paradox. Further, the decline of atmospheric OCS may have caused the late Archean glaciation....

  8. The small length scale effect for a non-local cantilever beam: a paradox solved.

    Science.gov (United States)

    Challamel, N; Wang, C M

    2008-08-27

    Non-local continuum mechanics allows one to account for the small length scale effect that becomes significant when dealing with microstructures or nanostructures. This paper presents some simplified non-local elastic beam models, for the bending analyses of small scale rods. Integral-type or gradient non-local models abandon the classical assumption of locality, and admit that stress depends not only on the strain value at that point but also on the strain values of all points on the body. There is a paradox still unresolved at this stage: some bending solutions of integral-based non-local elastic beams have been found to be identical to the classical (local) solution, i.e. the small scale effect is not present at all. One example is the Euler-Bernoulli cantilever nanobeam model with a point load which has application in microelectromechanical systems and nanoelectromechanical systems as an actuator. In this paper, it will be shown that this paradox may be overcome with a gradient elastic model as well as an integral non-local elastic model that is based on combining the local and the non-local curvatures in the constitutive elastic relation. The latter model comprises the classical gradient model and Eringen's integral model, and its application produces small length scale terms in the non-local elastic cantilever beam solution.

  9. Possibilities of using solar energy for solving environmental problems

    International Nuclear Information System (INIS)

    Allouache, A.; Brakeni, A.; Skrabalek, P.; Ornst, J.

    2012-01-01

    In this paper there are discussed the possibilities of using solar energy to power supply of electron accelerators that can be used to solve environmental problems, such as sewage treatment and radiation sterilization. Algeria, due to geographical location, has one of the largest 'solar deposits' around the world. Insolation time exceeds 2,000 hours per year and may reach up to 3,900 hours per year on the High Plains and the Sahara. Daily energy that falls on a horizontal surface one square meter is about 5 KWh on the most territory of Algeria, i.e. approximately 1,700 kWh per m 2 per year in the North and 2,263 kWh per m 2 per year in the south. Independent energy sources from the Sun can also bring economic development of the Sahara region.

  10. Messinian Salinity Crisis' Primary Evaporites: the shallow gypsum vs. deep dolomite formation paradox solved

    Science.gov (United States)

    De Lange, G. J.; Krijgsman, W.

    2015-12-01

    interpretations of evaporite formation mechanisms can thus account for the paradoxal, isochronous formation of shallow gypsum and deep-dolomite during the early MSC (1). (1) De Lange G.J. and Krijgsman W. (2010) Mar. Geol. 275, 273-277

  11. Solar energy in buildings solved by building information modeling

    Science.gov (United States)

    Chudikova, B.; Faltejsek, M.

    2018-03-01

    Building lead us to use renewable energy sources for all types of buildings. The use of solar energy is the alternatives that can be applied in a good ratio of space, price, and resultant benefits. Building Information Modelling is a modern and effective way of dealing with buildings with regard to all aspects of the life cycle. The basis is careful planning and simulation in the pre-investment phase, where it is possible to determine the effective result and influence the lifetime of the building and the cost of its operation. By simulating, analysing and insert a building model into its future environment where climate conditions and surrounding buildings play a role, it is possible to predict the usability of the solar energy and establish an ideal model. Solar systems also very affect the internal layout of buildings. Pre-investment phase analysis, with a view to future aspects, will ensure that the resulting building will be both low-energy and environmentally friendly.

  12. Entrepreneurial Regions: Do Macro-Psychological Cultural Characteristics of Regions Help Solve the "Knowledge Paradox" of Economics?

    Directory of Open Access Journals (Sweden)

    Martin Obschonka

    Full Text Available In recent years, modern economies have shifted away from being based on physical capital and towards being based on new knowledge (e.g., new ideas and inventions. Consequently, contemporary economic theorizing and key public policies have been based on the assumption that resources for generating knowledge (e.g., education, diversity of industries are essential for regional economic vitality. However, policy makers and scholars have discovered that, contrary to expectations, the mere presence of, and investments in, new knowledge does not guarantee a high level of regional economic performance (e.g., high entrepreneurship rates. To date, this "knowledge paradox" has resisted resolution. We take an interdisciplinary perspective to offer a new explanation, hypothesizing that "hidden" regional culture differences serve as a crucial factor that is missing from conventional economic analyses and public policy strategies. Focusing on entrepreneurial activity, we hypothesize that the statistical relation between knowledge resources and entrepreneurial vitality (i.e., high entrepreneurship rates in a region will depend on "hidden" regional differences in entrepreneurial culture. To capture such "hidden" regional differences, we derive measures of entrepreneurship-prone culture from two large personality datasets from the United States (N = 935,858 and Great Britain (N = 417,217. In both countries, the findings were consistent with the knowledge-culture-interaction hypothesis. A series of nine additional robustness checks underscored the robustness of these results. Naturally, these purely correlational findings cannot provide direct evidence for causal processes, but the results nonetheless yield a remarkably consistent and robust picture in the two countries. In doing so, the findings raise the idea of regional culture serving as a new causal candidate, potentially driving the knowledge paradox; such an explanation would be consistent with research on

  13. Entrepreneurial Regions: Do Macro-Psychological Cultural Characteristics of Regions Help Solve the "Knowledge Paradox" of Economics?

    Science.gov (United States)

    Obschonka, Martin; Stuetzer, Michael; Gosling, Samuel D; Rentfrow, Peter J; Lamb, Michael E; Potter, Jeff; Audretsch, David B

    2015-01-01

    In recent years, modern economies have shifted away from being based on physical capital and towards being based on new knowledge (e.g., new ideas and inventions). Consequently, contemporary economic theorizing and key public policies have been based on the assumption that resources for generating knowledge (e.g., education, diversity of industries) are essential for regional economic vitality. However, policy makers and scholars have discovered that, contrary to expectations, the mere presence of, and investments in, new knowledge does not guarantee a high level of regional economic performance (e.g., high entrepreneurship rates). To date, this "knowledge paradox" has resisted resolution. We take an interdisciplinary perspective to offer a new explanation, hypothesizing that "hidden" regional culture differences serve as a crucial factor that is missing from conventional economic analyses and public policy strategies. Focusing on entrepreneurial activity, we hypothesize that the statistical relation between knowledge resources and entrepreneurial vitality (i.e., high entrepreneurship rates) in a region will depend on "hidden" regional differences in entrepreneurial culture. To capture such "hidden" regional differences, we derive measures of entrepreneurship-prone culture from two large personality datasets from the United States (N = 935,858) and Great Britain (N = 417,217). In both countries, the findings were consistent with the knowledge-culture-interaction hypothesis. A series of nine additional robustness checks underscored the robustness of these results. Naturally, these purely correlational findings cannot provide direct evidence for causal processes, but the results nonetheless yield a remarkably consistent and robust picture in the two countries. In doing so, the findings raise the idea of regional culture serving as a new causal candidate, potentially driving the knowledge paradox; such an explanation would be consistent with research on the

  14. Tachyons without paradoxes

    International Nuclear Information System (INIS)

    Barrowes, S.C.

    1977-01-01

    Tachyon paradoxes, including causality paradoxes, have persisted within tachyon theories and left little hope for the existence of observable tachyons. A way is presented to solve the causality paradoxes, along with two other paradoxes, by the introduction of an absolute frame of reference in which a tachyon effect may never precede its cause. Relativity for ordinary matter is unaffected by this, even if the tachyons couple to ordinary particles. Violations of the principle of relativity due to the absolute frame would appear only in the case of free tachyons

  15. Paradoxes in probability theory

    CERN Document Server

    Eckhardt, William

    2013-01-01

    Paradoxes provide a vehicle for exposing misinterpretations and misapplications of accepted principles. This book discusses seven paradoxes surrounding probability theory.  Some remain the focus of controversy; others have allegedly been solved, however the accepted solutions are demonstrably incorrect. Each paradox is shown to rest on one or more fallacies.  Instead of the esoteric, idiosyncratic, and untested methods that have been brought to bear on these problems, the book invokes uncontroversial probability principles, acceptable both to frequentists and subjectivists. The philosophical disputation inspired by these paradoxes is shown to be misguided and unnecessary; for instance, startling claims concerning human destiny and the nature of reality are directly related to fallacious reasoning in a betting paradox, and a problem analyzed in philosophy journals is resolved by means of a computer program.

  16. CNO neutrino Grand Prix: the race to solve the solar metallicity problem

    Science.gov (United States)

    Cerdeño, David G.; Davis, Jonathan H.; Fairbairn, Malcolm; Vincent, Aaron C.

    2018-04-01

    Several next-generation experiments aim to make the first measurement of the neutrino flux from the Carbon-Nitrogen-Oxygen (CNO) solar fusion cycle. We calculate how much time these experiments will need to run for in order to measure this flux with enough precision to tell us the metal content of the Sun's core, and thereby help to solve the solar metallicity problem. For experiments looking at neutrino-electron scattering, we find that SNO+ will measure this CNO neutrino flux with enough precision after five years in its pure scintillator mode, provided its 210Bi background is measured to 1% accuracy. By comparison, a 100 ton liquid argon experiment such as Argo will take ten years in Gran Sasso lab, or five years in SNOLAB or Jinping. Borexino could obtain this precision in ten years, but this projection is very sensitive to background assumptions. For experiments looking at neutrino-nucleus scattering, the best prospects are obtained for low-threshold solid state detectors (employing either germanium or silicon). These would require new technologies to lower the experimental threshold close to detection of single electron-hole pairs, and exposures beyond those projected for next-generation dark matter detectors.

  17. Application of Solar Chimney Concept to Solve Potential Safety Issues of Nuclear Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    Khasawneh, Khalid; PARK, Youn Won [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2014-10-15

    In this paper two main events and their causes have been investigated and a potential alternative supporting system will be provided. The first event to be addressed is the Station Blackout (SBO) caused by the inherent unreliability of the Emergency Diesel Generators (EDGs) and Alternative AC (AAC) power sources. Different parameters affect The EDG unreliability; for instance, mechanical, operational, maintenance and surveillance. Those parameters will be analyzed and linked to plant safety and Core Damage Frequency (CDF). Also the AACs, the SBO diesel generators, will be studied and their operational requirements similarity with the EDGs will be discussed. The second event to be addressed is the Loss of Ultimate Heat Sink (LUHS) caused by the degradation of heat exchange effectiveness, that is, the poor heat transfer to the Ultimate Heat Sink (UHS). Different causes to such case were observed; intake lines blockages due to ice and foreign biological matters formation and oil spill near the heat sink causing the oil leakage to the heat exchangers tubes. The later cause, oil spill, has been given a special attention here due its potential effects for different nuclear power plants (NPPs) around the world; for example, Finland and the United Arab Emirates (UAE). For the Finnish case, the Finnish nuclear regulator (STUK) took already countermeasures for such scenario by introducing alternative heat sink, cooling towers, for the primary used heat sink, sea water, for one of its nuclear power plants. The abundance of the solar irradiation in the UAE region provides a perfect condition for the implementation of solar power applications. Utilizing this unique characteristic of that region may provide promising alternative and diverse options for solving potential safety related issues of their NPPs. The Solar Chimney Power Plant (SCPP) could be employed to serve as a supporting system to provide emergency power, in the case of SBO, and emergency cooling, in the case of

  18. Application of Solar Chimney Concept to Solve Potential Safety Issues of Nuclear Power Plants

    International Nuclear Information System (INIS)

    Khasawneh, Khalid; PARK, Youn Won

    2014-01-01

    In this paper two main events and their causes have been investigated and a potential alternative supporting system will be provided. The first event to be addressed is the Station Blackout (SBO) caused by the inherent unreliability of the Emergency Diesel Generators (EDGs) and Alternative AC (AAC) power sources. Different parameters affect The EDG unreliability; for instance, mechanical, operational, maintenance and surveillance. Those parameters will be analyzed and linked to plant safety and Core Damage Frequency (CDF). Also the AACs, the SBO diesel generators, will be studied and their operational requirements similarity with the EDGs will be discussed. The second event to be addressed is the Loss of Ultimate Heat Sink (LUHS) caused by the degradation of heat exchange effectiveness, that is, the poor heat transfer to the Ultimate Heat Sink (UHS). Different causes to such case were observed; intake lines blockages due to ice and foreign biological matters formation and oil spill near the heat sink causing the oil leakage to the heat exchangers tubes. The later cause, oil spill, has been given a special attention here due its potential effects for different nuclear power plants (NPPs) around the world; for example, Finland and the United Arab Emirates (UAE). For the Finnish case, the Finnish nuclear regulator (STUK) took already countermeasures for such scenario by introducing alternative heat sink, cooling towers, for the primary used heat sink, sea water, for one of its nuclear power plants. The abundance of the solar irradiation in the UAE region provides a perfect condition for the implementation of solar power applications. Utilizing this unique characteristic of that region may provide promising alternative and diverse options for solving potential safety related issues of their NPPs. The Solar Chimney Power Plant (SCPP) could be employed to serve as a supporting system to provide emergency power, in the case of SBO, and emergency cooling, in the case of

  19. A dynamic Thurstonian item response theory of motive expression in the picture story exercise: solving the internal consistency paradox of the PSE.

    Science.gov (United States)

    Lang, Jonas W B

    2014-07-01

    The measurement of implicit or unconscious motives using the picture story exercise (PSE) has long been a target of debate in the psychological literature. Most debates have centered on the apparent paradox that PSE measures of implicit motives typically show low internal consistency reliability on common indices like Cronbach's alpha but nevertheless predict behavioral outcomes. I describe a dynamic Thurstonian item response theory (IRT) model that builds on dynamic system theories of motivation, theorizing on the PSE response process, and recent advancements in Thurstonian IRT modeling of choice data. To assess the models' capability to explain the internal consistency paradox, I first fitted the model to archival data (Gurin, Veroff, & Feld, 1957) and then simulated data based on bias-corrected model estimates from the real data. Simulation results revealed that the average squared correlation reliability for the motives in the Thurstonian IRT model was .74 and that Cronbach's alpha values were similar to the real data (value of extant evidence from motivational research using PSE motive measures. (c) 2014 APA, all rights reserved.

  20. Is there really a Green Paradox?

    Energy Technology Data Exchange (ETDEWEB)

    Van der Ploeg, F. [University of Oxford, Oxford (United Kingdom); Withagen, C. [VU University, Amsterdam (Netherlands)

    2009-02-15

    The Green Paradox states that, in the absence of a tax on CO2 emissions, subsidizing a renewable backstop such as solar or wind energy brings forward the date at which fossil fuels become exhausted and consequently global warming is aggravated. We shed light on this issue by solving a model of depletion of non-renewable fossil fuels followed by a switch to a renewable backstop, paying attention to timing of the switch and the amount of fossil fuels remaining unexploited. We show that the Green Paradox occurs for relatively expensive but clean backstops (such as solar or wind), but does not occur if the backstop is sufficiently cheap relative to marginal global warming damages (e.g., nuclear energy) as then it is attractive to leave fossil fuels unexploited and thus limit CO2 emissions. We show that, without a CO2 tax, subsidizing the backstop might enhance welfare. If the backstop is relatively dirty and cheap (e.g., coal), there might be a period with simultaneous use of the non-renewable and renewable fuels. If the backstop is very dirty compared to oil or gas (e.g., tar sands), there is no simultaneous use. The optimum policy requires an initially rising CO2 tax followed by a gradually declining CO2 tax once the dirty backstop has been introduced. We also discuss the potential for limit pricing when the non-renewable resource is owned by a monopolist.

  1. Is there really a Green Paradox?

    International Nuclear Information System (INIS)

    Van der Ploeg, F.; Withagen, C.

    2009-02-01

    The Green Paradox states that, in the absence of a tax on CO2 emissions, subsidizing a renewable backstop such as solar or wind energy brings forward the date at which fossil fuels become exhausted and consequently global warming is aggravated. We shed light on this issue by solving a model of depletion of non-renewable fossil fuels followed by a switch to a renewable backstop, paying attention to timing of the switch and the amount of fossil fuels remaining unexploited. We show that the Green Paradox occurs for relatively expensive but clean backstops (such as solar or wind), but does not occur if the backstop is sufficiently cheap relative to marginal global warming damages (e.g., nuclear energy) as then it is attractive to leave fossil fuels unexploited and thus limit CO2 emissions. We show that, without a CO2 tax, subsidizing the backstop might enhance welfare. If the backstop is relatively dirty and cheap (e.g., coal), there might be a period with simultaneous use of the non-renewable and renewable fuels. If the backstop is very dirty compared to oil or gas (e.g., tar sands), there is no simultaneous use. The optimum policy requires an initially rising CO2 tax followed by a gradually declining CO2 tax once the dirty backstop has been introduced. We also discuss the potential for limit pricing when the non-renewable resource is owned by a monopolist.

  2. Radwaste paradox

    International Nuclear Information System (INIS)

    Carter, L.J.

    1983-01-01

    The Paradox Basin is one of the places where the US Department of Energy is looking for a site for a deep-mined repository for high-level radioactive waste. This seems appropriately symbolic because the geologic disposal problem has increasingly taken on the aspect of a political and technical conundrum, replete with real or seeming contradictions and paradoxes. A central paradox is that, while the concept of sequestering long-lived wastes in mined repositories is attractive intuitively, the very efforts made to confirm the suitability of particular rock formations give rise to further uncertainties. The new law contemplates repository construction will start as early as 1989. Experience so far at the several sites suggests that the technical and political questions tend to proliferate rather than diminish as more becomes known about the geology and hydrology. The following sites were discussed: the Hanford basalt; the Nevada tuff; and salt beds and salt domes (Utah, Texas, Mississippi). (DP)

  3. Quantum paradoxes and physical reality

    Energy Technology Data Exchange (ETDEWEB)

    Van der Merwe, Alwyn (Denver Univ., CO (USA). Dept. of Physics) (ed.); Selleri, Franco (Bologna Univ. (Italy). Ist. di Fisica)

    1990-01-01

    This book is devoted to the most fundamental themes of quantum physics: acausality, wave-particle duality, Einstein-Podolsky-Rosen (EPR) paradox, and so on. These are matters of growing interest for physicists. Several paradoxes have plagued quantum physics since its beginnings, the easiest of which to solve are the paradoxes of completeness (Schroedinger's cat, Wigner's friend, de Broglie's box, etc.). At a deeper level is the paradox of wave-particle duality whose solution probably requires the Einstein-de Broglie picture of atomic systems. The most difficult of them all is the EPR paradox (incompatibility between local realism and quantum theory). The book shows that experimental research can, in principle, solve paradoxes such as EPR and wave-particle duality but that the experiments performed on Bell-type inequalities have instead left the conceptual situation fundamentally unmodified. For a fair understanding of the Einstein-de Broglie and of the Bohr-Heisenberg ideas, an 'internal' lecture of physics is not enough. Such 'external' elements as individual biographies, history of culture, and philosophical preconceptions prove also to be important. (author). refs.; figs.; tabs.

  4. Quantum paradoxes and physical reality

    International Nuclear Information System (INIS)

    Van der Merwe, Alwyn; Selleri, Franco

    1990-01-01

    This book is devoted to the most fundamental themes of quantum physics: acausality, wave-particle duality, Einstein-Podolsky-Rosen (EPR) paradox, and so on. These are matters of growing interest for physicists. Several paradoxes have plagued quantum physics since its beginnings, the easiest of which to solve are the paradoxes of completeness (Schroedinger's cat, Wigner's friend, de Broglie's box, etc.). At a deeper level is the paradox of wave-particle duality whose solution probably requires the Einstein-de Broglie picture of atomic systems. The most difficult of them all is the EPR paradox (incompatibility between local realism and quantum theory). The book shows that experimental research can, in principle, solve paradoxes such as EPR and wave-particle duality but that the experiments performed on Bell-type inequalities have instead left the conceptual situation fundamentally unmodified. For a fair understanding of the Einstein-de Broglie and of the Bohr-Heisenberg ideas, an 'internal' lecture of physics is not enough. Such 'external' elements as individual biographies, history of culture, and philosophical preconceptions prove also to be important. (author). refs.; figs.; tabs

  5. Five paradox on energy system management

    International Nuclear Information System (INIS)

    Frisch, J.R.

    1995-01-01

    Five paradox are detailed on energy management: internationalization of energy questions but always regional management is present, short term problems must be solved but without forgetting long term problems in environment, the third paradox is : we have time but we are in a hurry, we have reserves but ten, twenty or thirty years are necessary to adapt our energy system; the fourth paradox is : we cannot manage energy by managing only energy, for example : finances system development and environment importance. The last and fifth paradox is : the market, yes, but state too, as regulative force

  6. What Paradox?

    DEFF Research Database (Denmark)

    Holt, Robin; Zundel, Mike

    2017-01-01

    This chapter investigates the relationship between paradox and the logical typing of classes and members. Class-based thinking affords efficiency in communication and the progressive, additive development of knowledge, but also creates fissures, shortcuts, truncations, and delimitations that gene......This chapter investigates the relationship between paradox and the logical typing of classes and members. Class-based thinking affords efficiency in communication and the progressive, additive development of knowledge, but also creates fissures, shortcuts, truncations, and delimitations...... that emphasizes interconnectedness and interdependency, which Gregory Bateson calls “grace”: the successful integration of smaller with wider arcs of awareness. This is developed here into a method for studying organizational phenomena using the example of an organizational routine, arguing that this may be one...

  7. Icarus Investigations: A Model for Engaging Citizen Scientists to Solve Solar Big Data Challenges

    Science.gov (United States)

    Winter, H. D., III; Loftus, K.

    2017-12-01

    Solar data is growing at an exponential rate. NASA's Atmospheric Imaging Assembly (AIA) has produced a data volume of over 6 petabytes to date, and that volume is growing. The initial suite of instruments on DKIST are expected to generate approximately 25TB of data per day, with bursts up to 50TB. Making sense of this deluge of solar data is as formidable a task as collecting it. New techniques and new ways of thinking are needed in order to optimize the value of this immense amount of data. While machine learning algorithms are a natural tool to sift through Big Data, those tools need to be carefully constructed and trained in order to provide meaningful results. Trained volunteers are needed to provide a large volume of initial classifications in order to properly train machine learning algorithms. To retain a highly trained pool of volunteers to teach machine learning algorithms, we propose to host an ever-changing array of solar-based citizen science projects under a single collaborative project banner: Icarus Investigations. Icarus Investigations would build and retain a dedicated user base within Zooniverse, the most popular citizen science website with over a million registered users. Volunteers will become increasingly comfortable with solar images and solar features of interest as they work on projects that focus on a wide array of solar phenomena. Under a unified framework, new solar citizen science projects submitted to Icarus Investigations will build on the successes, and learn from the missteps, of their predecessors. In this talk we discuss the importance and benefits of engaging the public in citizen science projects and call for collaborators on future citizen science projects. We will also demonstrate the initial Icarus Investigations project, The Where of the Flare. This demonstration will allow us to highlight the workflow of a Icarus Investigations citizen science project with a concrete example.

  8. Chemical Impact of Solar Energetic Particle Event From The Young Sun: Implications for the Origin of Prebiotic Chemistry and the Fain Young Sun Paradox

    Science.gov (United States)

    Airapetian, V.; Gronoff, G.; Hébrard, E.; Danchi, W.

    2015-12-01

    Understanding how the simple molecules present on the early Earth and possibly Mars may have set a path for complex biological molecules, the building blocks of life, represents one of greatest unsolved questions. Here we present a new model of the rise of the abiotic nitrogen fixation and associated pre-biotic chemistry in the early Earth and Mars atmosphere mediated by solar eruptive events. Our physical models of interaction of magnetic clouds ejected from the young Sun with magnetospheres of the early Earth show significant perturbations of geomagnetic fields that produce extended polar caps. These polar caps provide pathways for energetic particles associated with magnetic clouds to penetrate into the nitrogen-rich weakly reducing atmosphere and initiate the reactive chemistry by breaking molecular nitrogen, carbon dioxide, methane and producing hydrogen cyanide, the essential compound for life. The model also shows that contrary to the current models of warming of early Earth and Mars, major atmospheric constituents, CO2 and CH4 will be destroyed due to collisional dissociation with energetic particles. Instead, efficient formation of the potent greenhouse gas, nitrous oxide, as a by-product of these processes is expected. This mechanism can consistently explain the Faint Young Sun's paradox for the early atmospheres of Earth and Mars. Our new model provides insight into how life may have initiated on Earth and Mars and how to search for the spectral signatures on planets "pregnant" with the potential for life.

  9. Young Stars in Orion May Solve Mystery of Our Solar System

    Science.gov (United States)

    2001-09-01

    Scientists may have to give the Sun a little more credit. Exotic isotopes present in the early Solar System--which scientists have long-assumed were sprinkled there by a powerful, nearby star explosion--may have instead been forged locally by our Sun during the colossal solar-flare tantrums of its baby years. The isotopes--special forms of atomic nuclei, such as aluminum-26, calcium-41, and beryllium-10--can form in the X-ray solar flares of young stars in the Orion Nebula, which behave just like our Sun would have at such an early age. The finding, based on observations by the Chandra X-ray Observatory, has broad implications for the formation of our own Solar System. Eric Feigelson, professor of astronomy and astrophysics at Penn State, led a team of scientists on this Chandra observation and presents these results in Washington, D.C., today at a conference entitled "Two Years of Science with Chandra". "The Chandra study of Orion gives us the first chance to study the flaring properties of stars resembling the Sun when our solar system was forming," said Feigelson. "We found a much higher rate of flares than expected, sufficient to explain the production of many unusual isotopes locked away in ancient meteorites. If the young stars in Orion can do it, then our Sun should have been able to do it too." Scientists who study how our Solar System formed from a collapsed cloud of dust and gas have been hard pressed to explain the presence of these extremely unusual chemical isotopes. The isotopes are short-lived and had to have been formed no earlier than the creation of the Solar System, some five billion years ago. Yet these elements cannot be produced by a star as massive as our Sun under normal circumstances. (Other elements, such as silver and gold, were created long before the creation of the solar system.) The perplexing presence of these isotopic anomalies, found in ancient meteoroids orbiting the Earth, led to the theory that a supernova explosion occurred

  10. The paradox of scientific expertise

    DEFF Research Database (Denmark)

    Alrøe, Hugo Fjelsted; Noe, Egon

    2011-01-01

    Modern societies depend on a growing production of scientific knowledge, which is based on the functional differentiation of science into still more specialised scientific disciplines and subdisciplines. This is the basis for the paradox of scientific expertise: The growth of science leads to a f...... cross-disciplinary research and in the collective use of different kinds of scientific expertise, and thereby make society better able to solve complex, real-world problems.......Modern societies depend on a growing production of scientific knowledge, which is based on the functional differentiation of science into still more specialised scientific disciplines and subdisciplines. This is the basis for the paradox of scientific expertise: The growth of science leads...... to a fragmentation of scientific expertise. To resolve this paradox, the present paper investigates three hypotheses: 1) All scientific knowledge is perspectival. 2) The perspectival structure of science leads to specific forms of knowledge asymmetries. 3) Such perspectival knowledge asymmetries must be handled...

  11. Identity paradoxes

    Directory of Open Access Journals (Sweden)

    Đurić Jelena

    2010-01-01

    Full Text Available The article considers paradoxical nature of identity that emerges from: 1 the very concept of identity whose abstract generality unites various and even opposite features; 2 the processual nature of reality that is easier to express in the poetical metaphors or abstract principles than in unambiguous conceptual networks; 3 the oppose relationship between being and knowledge, mind and matter, subject and object, self and personality. Entangled in the labyrinth which evade efforts to be conceptually defined, the modern thinking of identity moves towards abandoning the idea of “self” on behalf of the “ego” and towards the misapprehension of identity as being identical. This corresponds to the “time of the lost spirit” stretched between the simultaneous need to find an identity and to give it up.

  12. Black Hole Paradox Solved By NASA's Chandra

    Science.gov (United States)

    2006-06-01

    Black holes are lighting up the Universe, and now astronomers may finally know how. New data from NASA's Chandra X-ray Observatory show for the first time that powerful magnetic fields are the key to these brilliant and startling light shows. It is estimated that up to a quarter of the total radiation in the Universe emitted since the Big Bang comes from material falling towards supermassive black holes, including those powering quasars, the brightest known objects. For decades, scientists have struggled to understand how black holes, the darkest objects in the Universe, can be responsible for such prodigious amounts of radiation. Animation of a Black Hole Pulling Matter from Companion Star Animation of a Black Hole Pulling Matter from Companion Star New X-ray data from Chandra give the first clear explanation for what drives this process: magnetic fields. Chandra observed a black hole system in our galaxy, known as GRO J1655-40 (J1655, for short), where a black hole was pulling material from a companion star into a disk. "By intergalactic standards J1655 is in our backyard, so we can use it as a scale model to understand how all black holes work, including the monsters found in quasars," said Jon M. Miller of the University of Michigan, Ann Arbor, whose paper on these results appears in this week's issue of Nature. Gravity alone is not enough to cause gas in a disk around a black hole to lose energy and fall onto the black hole at the rates required by observations. The gas must lose some of its orbital angular momentum, either through friction or a wind, before it can spiral inward. Without such effects, matter could remain in orbit around a black hole for a very long time. Illustration of Magnetic Fields in GRO J1655-40 Illustration of Magnetic Fields in GRO J1655-40 Scientists have long thought that magnetic turbulence could generate friction in a gaseous disk and drive a wind from the disk that carries angular momentum outward allowing the gas to fall inward. Using Chandra, Miller and his team provided crucial evidence for the role of magnetic forces in the black hole accretion process. The X-ray spectrum, the number of X-rays at different energies, showed that the speed and density of the wind from J1655's disk corresponded to computer simulation predictions for magnetically-driven winds. The spectral fingerprint also ruled out the two other major competing theories to winds driven by magnetic fields. "In 1973, theorists came up with the idea that magnetic fields could drive the generation of light by gas falling onto black holes," said co-author John Raymond of the Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass. "Now, over 30 years later, we finally may have convincing evidence." Evidence for Wind in the GRO J1655-40 Spectrum Evidence for Wind in the GRO J1655-40 Spectrum This deeper understanding of how black holes accrete matter also teaches astronomers about other properties of black holes, including how they grow. "Just as a doctor wants to understand the causes of an illness and not merely the symptoms, astronomers try to understand what causes phenomena they see in the Universe," said co-author Danny Steeghs also of the Harvard-Smithsonian Center for Astrophysics. "By understanding what makes material release energy as it falls onto black holes, we may also learn how matter falls onto other important objects." In addition to accretion disks around black holes, magnetic fields may play an important role in disks detected around young sun-like stars where planets are forming, as well as ultra-dense objects called neutron stars. NASA's Marshall Space Flight Center, Huntsville, Ala., manages the Chandra program for the agency's Science Mission Directorate. The Smithsonian Astrophysical Observatory controls science and flight operations from the Chandra X-ray Center, Cambridge, Mass. Additional information and images can be found at: http://chandra.harvard.edu and http://chandra.nasa.gov

  13. Paradoxes in aerohydrodynamics

    CERN Document Server

    Yershin, Shakhbaz A

    2017-01-01

    This book, on the general topic of hydroaerodynamics, investigates a number of exciting applications in this field, addressing specifically issues that allow seemingly paradoxical issues to be dealt with. The first part is devoted to the study of channel flows, in particular the lateral flow of a viscous and viscous-plastic liquid in a ring channel formed by coaxial cylinders. Specifically, the problem of dissipation of mechanical energy in channel flows of highly viscous liquids is addressed and solved. Furthermore, the mechanism leading to hydrodynamic erosion in intra-field pipelines (known as "channelized effect") is identified. Subsequently, a theory for channel flows with mass transfer through porous walls is developed. In the second part, viscous liquid free flows (jets) are investigated. In particular, a dispersion law for turbulent flow is derived and the existence of dynamic invariance in wake flows of variable density is demonstrated. The third part presents new insights from both theoretical and e...

  14. How to solve materials and design problems in solar heating and cooling. Energy technology review No. 77

    Energy Technology Data Exchange (ETDEWEB)

    Ward, D.S.; Oberoi, H.S.; Weinstein, S.D.

    1982-01-01

    A broad range of difficulties encountered in active and passive solar space heating systems and active solar space cooling systems is covered. The problems include design errors, installation mistakes, inadequate durability of materials, unacceptable reliability of components, and wide variations in performance and operation of different solar systems. Feedback from designers and manufacturers involved in the solar market is summarized. The designers' experiences with and criticisms of solar components are presented, followed by the manufacturers' replies to the various problems encountered. Information is presented on the performance and operation of solar heating and cooling systems so as to enable future designs to maximize performance and eliminate costly errors. (LEW)

  15. Is the EPR paradox really a paradox?

    OpenAIRE

    Tartaglia, A.

    1998-01-01

    The EPR paradox and the meaning of the Bell inequality are discussed. It is shown that considering the quantum objects as carrying with them ''instruction kits'' telling them what to do when meeting a measurement apparatus any paradox disappears. In this view the quantum state is characterized by the prescribed behaviour rather than by the specific value a parameter assumes as a result of an interaction.

  16. Tachyons and causal paradoxes

    International Nuclear Information System (INIS)

    Maund, J.B.

    1979-01-01

    Although the existence of tachyons is not ruled out by special relativity, it appears that causal paradoxes will arise if there are tachyons. The usual solutions to these paradoxes employ some form of the reinterpretation principle. In this paper it is argued first that, the principle is incoherent, second, that even if it is not, some causal paradoxes remain, and third, the most plausible ''solution,'' which appeals to boundary conditions of the universe, will conflict with special relativity

  17. Mathematical fallacies and paradoxes

    CERN Document Server

    Bunch, Bryan

    1982-01-01

    Stimulating, thought-provoking analysis of the most interesting intellectual inconsistencies in mathematics, physics, and language, including being led astray by algebra (De Morgan's paradox). 1982 edition.

  18. Generalized Hardy's Paradox

    Science.gov (United States)

    Jiang, Shu-Han; Xu, Zhen-Peng; Su, Hong-Yi; Pati, Arun Kumar; Chen, Jing-Ling

    2018-01-01

    Here, we present the most general framework for n -particle Hardy's paradoxes, which include Hardy's original one and Cereceda's extension as special cases. Remarkably, for any n ≥3 , we demonstrate that there always exist generalized paradoxes (with the success probability as high as 1 /2n -1) that are stronger than the previous ones in showing the conflict of quantum mechanics with local realism. An experimental proposal to observe the stronger paradox is also presented for the case of three qubits. Furthermore, from these paradoxes we can construct the most general Hardy's inequalities, which enable us to detect Bell's nonlocality for more quantum states.

  19. Paradoxical cerebral air embolism

    International Nuclear Information System (INIS)

    Lopez-Negrete, L.; Garcia-Lozano, J.; Sanchez, J. L.; Sala, J.

    2000-01-01

    We present a fatal case of intracranial air embolism produced by the passage of intravenous air to the arteries owing to the existence of a patent foremen ovale associated with pulmonary hypertension, which permitted a right-left shunt (paradoxical embolism). The pathophysiological mechanisms of pneumcephalus and paradoxical embolism are discussed and the pertinent literature is reviewed. (Author) 6 refs

  20. Electromagnetic reaction paradox

    International Nuclear Information System (INIS)

    Aspden, H.

    1984-01-01

    Alternative explanations for free-electron diamagnetism appear paradoxical and inconsistent with the reactive induction properties of magnetic materials. It is shown that the paradox can be eliminated by a generalized definition of the magnetic field with interesting spin-off consequences, including a justification for the anomalous doubling of the positron's effective mass in a free-electron environment

  1. The Statistical Fermi Paradox

    Science.gov (United States)

    Maccone, C.

    2008. 4. A practical example is then given of how the SEH works numerically. Each of the ten random variables is uniformly distributed around its own mean value as given by Dole (1964) and a standard deviation of 10% is assumed. The conclusion is that the average number of habitable planets in the Galaxy should be around 100 million ±200 million, and the average distance in between any two nearby habitable planets should be about 88 light years ±40 light years. 5. The SEH results are matched against the results of the Statistical Drake Equation from reference 4. As expected, the number of currently communicating ET civilizations in the Galaxy turns out to be much smaller than the number of habitable planets (about 10,000 against 100 million, i.e. one ET civilization out of 10,000 habitable planets). The average distance between any two nearby habitable planets is much smaller that the average distance between any two neighbouring ET civilizations: 88 light years vs. 2000 light years, respectively. This means an ET average distance about 20 times higher than the average distance between any pair of adjacent habitable planets. 6. Finally, a statistical model of the Fermi Paradox is derived by applying the above results to the coral expansion model of Galactic colonization. The symbolic manipulator "Macsyma" is used to solve these difficult equations. A new random variable Tcol, representing the time needed to colonize a new planet is introduced, which follows the lognormal distribution, Then the new quotient random variable Tcol/D is studied and its probability density function is derived by Macsyma. Finally a linear transformation of random variables yields the overall time TGalaxy needed to colonize the whole Galaxy. We believe that our mathematical work in deriving this STATISTICAL Fermi Paradox is highly innovative and fruitful for the future.

  2. Quantum Quasi-Paradoxes and Quantum Sorites Paradoxes

    CERN Document Server

    Smarandache, F

    1997-01-01

    There can be generated many paradoxes or quasi-paradoxes that may occur from the combination of quantum and non-quantum worlds in physics. Even the passage from the micro-cosmos to the macro-cosmos, and reciprocally, can generate unsolved questions or counter-intuitive ideas. We define a quasi-paradox as a statement which has a prima facie self-contradictory support or an explicit contradiction, but which is not completely proven as a paradox. We present herein four elementary quantum quasi-paradoxes and their corresponding quantum Sorites paradoxes, which form a class of quantum quasi-paradoxes.

  3. Quantum Quasi-Paradoxes and Quantum Sorites Paradoxes

    Directory of Open Access Journals (Sweden)

    Smarandache F.

    2005-04-01

    Full Text Available There can be generated many paradoxes or quasi-paradoxes that may occur from the combination of quantum and non-quantum worlds in physics. Even the passage from the micro-cosmos to the macro-cosmos, and reciprocally, can generate unsolved questions or counter-intuitive ideas. We define a quasi-paradox as a statement which has a prima facie self-contradictory support or an explicit contradiction, but which is not completely proven as a paradox. We present herein four elementary quantum quasi-paradoxes and their corresponding quantum Sorites paradoxes, which form a class of quantum quasi-paradoxes.

  4. Paradoxes in Practice

    DEFF Research Database (Denmark)

    Madsen, Charlotte Øland; Schulze, Pernille; Larsen, Mette Vinther

    The purpose of this paper is to explore how paradoxes unfold in management practices and how moments of relational dialogic, self-reflexive learning can transform these paradoxes into new understandings of the complexities of organizing and management. We work with paradox, not as a label...... to explore ‘the flux of reality from within’ with the managers. We therefore draw on Bakhtin’s ideas regarding ongoing centripetal (monologic) and centrifugal (dialogic) forces of language and aim to demonstrate how working with language and the awareness of the embodied embedded practices at the same time...

  5. The Simpson's paradox unraveled

    DEFF Research Database (Denmark)

    Hernán, Miguel A; Clayton, David; Keiding, Niels

    2011-01-01

    Background In a famous article, Simpson described a hypothetical data example that led to apparently paradoxical results. Methods We make the causal structure of Simpson’s example explicit. Results We show how the paradox disappears when the statistical analysis is appropriately guided by subject......-matter knowledge. We also review previous explanations of Simpson’s paradox that attributed it to two distinct phenomena: confounding and non-collapsibility. Conclusion Analytical errors may occur when the problem is stripped of its causal context and analyzed merely in statistical terms....

  6. The Tolman-Regge antitelephone paradox: Its solution by tachyon mechanics

    International Nuclear Information System (INIS)

    Recami, E.

    The possibility of solving (at least 'in microphysics') all the ordinary causal paradoxes devised for Tachyons is not yet widely recognized; on the contrary, the effectiveness of the Stuckelberg-Feynman 'switching principle' is often misunderstood. It is therefore shown in details and rigorously how to solve the oldest causal paradox, originally proposed by Tolman, which is the Kernel of so many further tachyon paradoxes. The key to the solution is a careful application of Tachyon Kinematics. Which can be unambiguously derived from Special Relativity. A systematic, thorough analysis of all tachyon paradoxes is going to appear elsewhere. (Author) [pt

  7. The core paradox.

    Science.gov (United States)

    Kennedy, G. C.; Higgins, G. H.

    1973-01-01

    Rebuttal of suggestions from various critics attempting to provide an escape from the seeming paradox originated by Higgins and Kennedy's (1971) proposed possibility that the liquid in the outer core was thermally stably stratified and that this stratification might prove a powerful inhibitor to circulation of the outer core fluid of the kind postulated for the generation of the earth's magnetic field. These suggestions are examined and shown to provide no reasonable escape from the core paradox.

  8. An American Paradox

    International Nuclear Information System (INIS)

    Jamieson, D.

    2006-01-01

    This paper explores the paradox that while Americans generally identify themselves as environmentalists, they show little willingness to voluntarily restrain their behavior or to support specific fiscal policies that would result in increased levels of environmental protection. I explore the role of values in the explanation of this paradox, and discuss some of the difficulties involved in studying values and their role in human behavior

  9. Man Is a Paradox

    Institute of Scientific and Technical Information of China (English)

    王茂娟

    2009-01-01

    In the poem "Always", the author Pablo Neruda employs the first person narration to incisively reveal the paradoxical traits in human nature by exploring man in relation to love. "I" play a role shifting from a calm narrator to a furious one, and the last recovering to a mild one, which offers a multiple visual angle to observe humanity. In sum, by means of continuous changes of my inner feelings in the poem, Pablo Neruda reveals the paradoxical humanity .

  10. Extending Cantor Paradox

    OpenAIRE

    Leon, Antonio

    2008-01-01

    The inconsistencies involved in the foundation of set theory were invariably caused by infinity and self-reference; and only with the opportune axiomatic restrictions could them be obviated. Throughout history, both concepts have proved to be an exhaustible source of paradoxes and contradictions. It seems therefore legitimate to pose some questions concerning their formal consistency. This is just the objective of this paper. Starting from an extension of Cantor's paradox that suggests the in...

  11. The quercetin paradox

    International Nuclear Information System (INIS)

    Boots, Agnes W.; Li, Hui; Schins, Roel P.F.; Duffin, Rodger; Heemskerk, Johan W.M.; Bast, Aalt; Haenen, Guido R.M.M.

    2007-01-01

    Free radical scavenging antioxidants, such as quercetin, are chemically converted into oxidation products when they protect against free radicals. The main oxidation product of quercetin, however, displays a high reactivity towards thiols, which can lead to the loss of protein function. The quercetin paradox is that in the process of offering protection, quercetin is converted into a potential toxic product. In the present study, this paradox is evaluated using rat lung epithelial (RLE) cells. It was found that quercetin efficiently protects against H 2 O 2 -induced DNA damage in RLE cells, but this damage is swapped for a reduction in GSH level, an increase in LDH leakage as well as an increase of the cytosolic free calcium concentration. To our knowledge, this is the first study that indicates that the quercetin paradox, i.e. the exchange of damage caused by quercetin and its metabolites, also occurs in living lung cells. Following depletion of GSH in the cells by BSO pre-treatment, this quercetin paradox becomes more pronounced, confirming that the formation of thiol reactive quercetin metabolites is involved in the quercetin paradox. The quercetin paradox in living cells implies that the anti-oxidant directs oxidative damage selectively to thiol arylation. Apparently, the potential toxicity of metabolites formed during the actual antioxidant activity of free radical scavengers should be considered in antioxidant supplementation

  12. Managing operational paradoxes

    International Nuclear Information System (INIS)

    Olson, J.; Baker, K.; Thurber, J.

    1992-01-01

    The economic, regulatory, and social environment of commercial nuclear power has changed dramatically in the last 10 yr. In addition to the increased regulatory pressure resulting from the Three Mile Island incident and other factors, nuclear utilities have experienced increasing financial pressure from state public utility commissions and investors. To successfully manage nuclear power plants in today's environment requires different skills and strategies than were required 10 yr ago. External pressures on the utility and plant organization have created a series of operational paradoxes unmatched in the history of commercial nuclear power. This paper is based on a synthesis of findings and observations from a series of studies conducted by the authors over the past 10 yr. The authors identify a series of specific paradoxes facing managers of nuclear power plants and suggest several strategies for managing these paradoxes

  13. Black Hole Paradoxes

    International Nuclear Information System (INIS)

    Joshi, Pankaj S.; Narayan, Ramesh

    2016-01-01

    We propose here that the well-known black hole paradoxes such as the information loss and teleological nature of the event horizon are restricted to a particular idealized case, which is the homogeneous dust collapse model. In this case, the event horizon, which defines the boundary of the black hole, forms initially, and the singularity in the interior of the black hole at a later time. We show that, in contrast, gravitational collapse from physically more realistic initial conditions typically leads to the scenario in which the event horizon and space-time singularity form simultaneously. We point out that this apparently simple modification can mitigate the causality and teleological paradoxes, and also lends support to two recently suggested solutions to the information paradox, namely, the ‘firewall’ and ‘classical chaos’ proposals. (paper)

  14. Introducing the Levinthal's Protein Folding Paradox and Its Solution

    Science.gov (United States)

    Martínez, Leandro

    2014-01-01

    The protein folding (Levinthal's) paradox states that it would not be possible in a physically meaningful time to a protein to reach the native (functional) conformation by a random search of the enormously large number of possible structures. This paradox has been solved: it was shown that small biases toward the native conformation result…

  15. Paradoxical embolism: computed tomography demonstration

    International Nuclear Information System (INIS)

    Kaye, J.; Hayward, M.

    2001-01-01

    Paradoxical emboli are rare and often presumptively diagnosed. A case of paradoxical embolism, in which both the arterial and venous emboli were documented on CT, is described. While paradoxical emboli are not infrequently diagnosed clinically on a presumptive basis, it is rare to document them with imaging such as CT which, in the present case, confirmed the diagnosis. Copyright (2001) Blackwell Science Pty Ltd

  16. Adaptationism fails to resolve Fermi's paradox

    Directory of Open Access Journals (Sweden)

    Ćirković Milan M.

    2005-01-01

    Full Text Available One of the most interesting problems in the nascent discipline of astrobiology is more than half-century old Fermi's paradox: why, considering extraordinary young age of Earth and the Solar System in the Galactic context, don't we perceive much older intelligent communities or signposts of their activity? In spite of a vigorous research activity in recent years, especially bolstered by successes of astrobiology in finding extrasolar planets and extremophiles, this problem (also known as the "Great Silence" or "astrosociological" paradox remains as open as ever. In a previous paper, we have discussed a particular evolutionary solution suggested by Karl Schroeder based on the currently dominant evolutionary doctrine of adaptationism. Here, we extend that discussion with emphasis on the problems such a solution is bound to face, and conclude that it is ultimately quite unlikely. .

  17. The happiness paradox

    NARCIS (Netherlands)

    Bollen, Johan; Gonçalves, Bruno; Leemput, van de Ingrid; Ruan, Guangchen

    2017-01-01

    Most individuals in social networks experience a so-called Friendship Paradox: they are less popular than their friends on average. This effect may explain recent findings that widespread social network media use leads to reduced happiness. However the relation between popularity and happiness is

  18. Paradoxes of unstable electron

    International Nuclear Information System (INIS)

    Okun, L.B.; Zeldovich, Ya.B.

    1978-01-01

    The hypothesis that electron is unstable - when it is consistent with the vanishing mass of the photon- leads to a number of paradoxical statements. The lifetime of the electron is determined by emission of a huge number of longitudinal photons and exponentially depends on the amount of emitted energy. This suggests to discuss searches for charge nonconservation in experiments with high energy particles

  19. The Paradox of Analogy

    Directory of Open Access Journals (Sweden)

    David Botting

    2012-03-01

    Full Text Available I will show that there is a type of analogical reasoning that instantiates a pattern of reasoning in confirmation theory that is considered at best paradoxical and at worst fatal to the entire syntactical approach to confirmation and explanation. However, I hope to elaborate conditions under which this is a sound (although not necessarily strong method of reasoning.

  20. Adiposopathy and Obesity Paradox

    Directory of Open Access Journals (Sweden)

    Indriyanti Rafi Sukmawati

    2013-04-01

    Full Text Available BACKGROUND: Obesity has reached global epidemic proportions in both adults and children and is associated with numerous comorbidities, including hypertension, type 2 diabetes mellitus (T2DM, dyslipidemia and major cardiovascular diseases (CVD. CONTENT: Adiposity may cause adipocyte and adipose tissue anatomic and functional abnormalities, termed adiposopathy (adipose-opathy or "sick fat," that result in endocrine and immune derangements. Adiposopathy may directly contribute to CVD through pericardiac and perivascular effects on the myocardium and blood vessels. Adiposopathy may also indirectly contribute to CVD through promoting or worsening major CVD risk factors such as T2DM, high blood pressure, and dyslipidemia. Despite this adverse association, numerous studies have documented an obesity paradox in which overweight and obese people with established CVD, including hypertension, heart failure, coronary heart disease, and peripheral arterial disease, have a better prognosis compared with nonoverweight/nonobese patients. These paradoxical findings are made less paradoxical when the pathogenic potential of excessive body fat is assessed based on adipose tissue dysfunction rather than simply on increased fat mass alone. SUMMARY: Adiposopathy is defined as pathological adipose tissue function that may be promoted and exacerbated by fat accumulation (adiposity and sedentary lifestyle in genetically susceptible patients. Adiposopathy is a root cause of some of the most common metabolic diseases observed in clinical practice, including T2DM, hypertension and dyslipidemia. KEYWORDS: adiposopathy, adiposity, obesity paradox, adipocyte dysfunction, adipose hypertrophy, adipose hyperplasia.

  1. New physics and paradox

    International Nuclear Information System (INIS)

    Van der Spuy, E.

    1983-01-01

    Conflict between the finite and infinite in theoretical physics often results in paradox. By measuring phenomena for which such conflict exists, physicists may be able to discover in each case the basis of the conflict and thus may eventually reformulate physical laws

  2. The Amazon's energetic paradox

    International Nuclear Information System (INIS)

    Silva, Marcos Vinicius Miranda da; Bermann, Celio

    1999-01-01

    The main energy sources in Amazon region are hydroelectric, biomass, and natural gas. Although abundance of these resources, the energy consumption in this region is one of the most low of Brazil. The article overviews this paradox. In this context, economical, geopolitical, and technical aspects are presented

  3. The nuclear paradox

    International Nuclear Information System (INIS)

    Eibenschutz, J.

    1989-01-01

    In this work it is discussed the nuclear paradox. One side, the nuclear power is important for technological development, on the other hand, it has been frequently questioned by society. It is pointed out as well, that many other factors are more dangerous to man such as environment polution. (A.C.A.S.)

  4. The Hydrostatic Paradox.

    Science.gov (United States)

    Wilson, Alpha E.

    1995-01-01

    Presents an example demonstrating the quantitative resolution of the hydrostatic paradox which is the realization that the force due to fluid pressure on the bottom of a vessel can be considerably greater or considerably less than the weight of the fluid in the vessel. (JRH)

  5. A Hydrostatic Paradox Revisited

    Science.gov (United States)

    Ganci, Salvatore

    2012-01-01

    This paper revisits a well-known hydrostatic paradox, observed when turning upside down a glass partially filled with water and covered with a sheet of light material. The phenomenon is studied in its most general form by including the mass of the cover. A historical survey of this experiment shows that a common misunderstanding of the phenomenon…

  6. On the solution of the EPR paradox and the explanation of the violation of Bell's inequality

    OpenAIRE

    Bene, Gyula

    1997-01-01

    A new interpretation offers a consistent conceptual basis for nonrelativistic quantum mechanics. The Einstein-Podolsky-Rosen (EPR) paradox is solved and the violation of Bell's inequality is explained by maintaining realism, inductive inference and Einstein separability.

  7. The Paradoxes of Liberalism

    DEFF Research Database (Denmark)

    Thompson, Grahame

    2011-01-01

    Jakob Vestergaard has produced one of the most telling analyses of the international financial architecture by deploying a broadly Foucauldian framework that invokes a novel description of neo-liberal governance, one organized around discipline, conditional exceptions and the pursuit of a ‘proper...... economy’. This review both welcomes but challenges some of Vestergaard's analysis. In so doing it explores further the paradoxes of liberalism and the fate of sovereignty in the current international context....

  8. Introduction, Copyright's Paradox

    OpenAIRE

    Netanel, Neil

    2008-01-01

    The United States Supreme Court famously labeled copyright “the engine of free expression” because it provides a vital economic incentive for much of the literature, commentary, music, art, and film that makes up our public discourse. Yet today’s greatly expanded copyright law often does the opposite—it can be used to quash news reporting, political commentary, church dissent, historical scholarship, cultural critique, and artistic expression. In Copyright’s Paradox, Neil Weinstock ...

  9. Paradoxes of maternal mourning.

    Science.gov (United States)

    Brice, C W

    1991-02-01

    It has been customary to conceptualize mourning as a phasic or stage phenomenon (Lindemann 1944; Parkes 1972; Bowlby 1980; Knapp 1986). Such a conceptualization has proved to be of tremendous didactic value, especially in terms of succinctly organizing and communicating the major affects, behaviors, and reactions of mourning. It is, however, my belief, based upon clinical experience with many forms of bereavement, that the phenomenon of mourning is not comprised of clearly delineated stages and phases. I have come to conceptualize the phenomenon of mourning the death of a loved person as involving the bereaved's struggle with a series of more or less unresolvable paradoxes rather than as a progression through stages that possess relatively distinct and predictable beginning and ending points. The specific paradoxes encountered by a bereaved person differ, of course, in accordance with the relationship that was lost (mother, father, spouse, child, or sibling), the developmental stage of the bereaved (childhood, adolescence, adulthood, or maturity), the type of death (sudden or prolonged), and the cause of death (illness, murder, suicide, or accident). In this paper, I will address those paradoxes that seem specific to maternal mourning - that is, to mothers who are mourning the death of a child.

  10. Paradoxes and Innovation in Family Firms

    DEFF Research Database (Denmark)

    Ingram, Amy E.; Lewis, Marianne W.; Barton, Sid

    2016-01-01

    thinkers are more likely to manage these tensions and fuel innovative behavior. Leveraging family business and organizational paradox literatures, this multi-stage exploratory study develops measures of paradoxical tensions and paradoxical thinking in family firms, and tests these propositions. Findings...... indicate that paradoxical tensions may stymie innovative behavior, but that leaders' paradoxical thinking is positively related to innovative behavior....

  11. Problem Solving in Practice

    Science.gov (United States)

    Greene, Kim; Heyck-Williams, Jeff; Timpson Gray, Elicia

    2017-01-01

    Problem solving spans all grade levels and content areas, as evidenced by this compilation of projects from schools across the United States. In one project, high school girls built a solar-powered tent to serve their city's homeless population. In another project, 4th graders explored historic Jamestown to learn about the voices lost to history.…

  12. Einstein and the twin paradox

    International Nuclear Information System (INIS)

    Pesic, Peter

    2003-01-01

    Einstein was the first to discuss and resolve the 'twin paradox', which in 1905 he did not consider paradoxical and treated as a consequence of lack of simultaneity. He maintained this view until at least 1914. However, in 1918 Einstein brought forward arguments about accelerated frames of reference that tended to overshadow his initial resolution. His earlier arguments were gradually rediscovered during the subsequent controversy about this 'paradox'

  13. Comment on the extinct paradox

    International Nuclear Information System (INIS)

    Levine, D.M.

    1983-11-01

    The extinction paradox is a contradiction between geometrical optics results which predict that at high frequencies the scattering cross section of an object should equal its geometrical cross section and rigorous scattering theory which shows that at high frequencies the scattering cross section approaches twice the geometrical cross section of the object. Confusion about the reason for this paradox persists today even though the nature of the paradox was correctly identified many years ago by Brillouin. The resolution of the paradox is restated and illustrated with an example, and then the implications to the interpretation of scattering cross sections are identified

  14. On Aerts' overlooked solution to the EPR paradox

    OpenAIRE

    de Bianchi, Massimiliano Sassoli

    2018-01-01

    The Einstein-Podolsky-Rosen (EPR) paradox was enunciated in 1935 and since then it has made a lot of ink flow. Being a subtle result, it has also been largely misunderstood. Indeed, if questioned about its solution, many physicists will still affirm today that the paradox has been solved by the Bell-test experimental results, which have shown that entangled states are real. However, this remains a wrong view, as the validity of the EPR ex-absurdum reasoning is independent from the Bell-test e...

  15. Simpson's Paradox, Lord's Paradox, and Suppression Effects are the same phenomenon – the reversal paradox

    Directory of Open Access Journals (Sweden)

    Gunnell David

    2008-01-01

    Full Text Available Abstract This article discusses three statistical paradoxes that pervade epidemiological research: Simpson's paradox, Lord's paradox, and suppression. These paradoxes have important implications for the interpretation of evidence from observational studies. This article uses hypothetical scenarios to illustrate how the three paradoxes are different manifestations of one phenomenon – the reversal paradox – depending on whether the outcome and explanatory variables are categorical, continuous or a combination of both; this renders the issues and remedies for any one to be similar for all three. Although the three statistical paradoxes occur in different types of variables, they share the same characteristic: the association between two variables can be reversed, diminished, or enhanced when another variable is statistically controlled for. Understanding the concepts and theory behind these paradoxes provides insights into some controversial or contradictory research findings. These paradoxes show that prior knowledge and underlying causal theory play an important role in the statistical modelling of epidemiological data, where incorrect use of statistical models might produce consistent, replicable, yet erroneous results.

  16. The Teacher's Paradox

    Science.gov (United States)

    Lilyquist, J. Gary

    1998-06-01

    New findings suggest that the way in which schools conduct their business is blocking our educational system from improving at a rate required to meet society's needs. A ground theory developed by exploring six organizational dimensions: external and internal environment cultures, leadership, strategy, structure, and results, verified the existence of the teacher's paradox. Implications suggest educational reformers must rethink approaches to school improvement by work within cultural boundaries. The forth coming book, "Are schools really like this?" presents "The Balance Alignment Model and Theory" to improve our schools using system thinking.

  17. The social dominance paradox.

    Science.gov (United States)

    Cook, Jennifer Louise; den Ouden, Hanneke E M; Heyes, Cecilia M; Cools, Roshan

    2014-12-01

    Dominant individuals report high levels of self-sufficiency, self-esteem, and authoritarianism. The lay stereotype suggests that such individuals ignore information from others, preferring to make their own choices. However, the nonhuman animal literature presents a conflicting view, suggesting that dominant individuals are avid social learners, whereas subordinates focus on learning from private experience. Whether dominant humans are best characterized by the lay stereotype or the animal view is currently unknown. Here, we present a "social dominance paradox": using self-report scales and computerized tasks, we demonstrate that socially dominant people explicitly value independence, but, paradoxically, in a complex decision-making task, they show an enhanced reliance (relative to subordinate individuals) on social learning. More specifically, socially dominant people employed a strategy of copying other agents when the agents' responses had a history of being correct. However, in humans, two subtypes of dominance have been identified: aggressive and social. Aggressively dominant individuals, who are as likely to "get their own way" as socially dominant individuals but who do so through the use of aggressive or Machiavellian tactics, did not use social information, even when it was beneficial to do so. This paper presents the first study of dominance and social learning in humans and challenges the lay stereotype in which all dominant individuals ignore others' views. The more subtle perspective we offer could have important implications for decision making in both the boardroom and the classroom. Copyright © 2014 Elsevier Ltd. All rights reserved.

  18. The Paradox of Openness

    DEFF Research Database (Denmark)

    Laursen, Keld; Salter, Ammon

    2014-01-01

    To innovate, firms often need to draw from, and collaborate with, a large number of actors from outside their organization. At the same time, firms need also to be focused on capturing the returns from their innovative ideas. This gives rise to a paradox of openness—the creation of innovations of...... or collaborate with competitors. We explore the implications of these findings for the literature on open innovation and innovation strategy.......To innovate, firms often need to draw from, and collaborate with, a large number of actors from outside their organization. At the same time, firms need also to be focused on capturing the returns from their innovative ideas. This gives rise to a paradox of openness—the creation of innovations...... often requires openness, but the commercialization of innovations requires protection. Based on econometric analysis of data from a UK innovation survey, we find a concave relationship between firms’ breadth of external search and formal collaboration for innovation, and the strength of the firms...

  19. Can Cybersemiotics Solve the Paradox of Transdisciplinary Knowing?

    DEFF Research Database (Denmark)

    Brier, Søren

    2014-01-01

    conceived, connects our perception with our thinking, communication, and acting in the social world. Unfortunately,each of the four worlds has historically developed its own type of narrative, with its own fundamentalist and reductionist verions vitiating the project of transdisciplinarity. Physicists...... and chemists tend to view the universe as consisting of matter, forces, and energy. Mechanistically oriented biologists extend this view into their subject area. But cybernetic- and semiotic-oriented biologists perceive living systems as the basic organizers of reality, possessing self-protecting, and self...

  20. Puzzles, paradoxes, and problem solving an introduction to mathematical thinking

    CERN Document Server

    Reba, Marilyn A

    2014-01-01

    Graphs: Puzzles and Optimization Graphical Representation and Search Greedy Algorithms and Dynamic Programming Shortest Paths, DNA Sequences, and GPS Systems Routing Problems and Optimal Circuits Traveling Salesmen and Optimal Orderings Vertex Colorings and Edge Matchings Logic: Rational Inference and Computer Circuits Inductive and Deductive Arguments Deductive Arguments and Truth-Tables Deductive Arguments and Derivations Deductive Logic and Equivalence Modeling Using Deductive Logic Probability: Predictions and Expectations Probability and Counting Counting and Unordered Outcomes Independen

  1. Solving the Sophistication-Population Paradox of Game Refinement Theory

    OpenAIRE

    Xiong , Shuo; Tiwary , Parth ,; Iida , Hiroyuki

    2016-01-01

    Part 4: Short Papers; International audience; A mathematical model of game refinement was proposed based on uncertainty of game outcome. This model has been shown to be useful in measuring the entertainment element in the domains such as boardgames and sport games. However, game refinement theory has not been able to explain the correlation between the popularity of a game and the game refinement value. This paper introduces another aspect in the study of game entertainment, the concept of “a...

  2. Mimesis, fiction, paradoxes

    Directory of Open Access Journals (Sweden)

    Françoise Lavocat

    2010-04-01

    Full Text Available Les théories contemporaines de la fiction, comme les poétiques de la Renaissance, privilégient une conception de la mimesis fondée sur la vraisemblance : la démonstration du profit cognitif et moral de la fiction passe toujours par une définition de l’imitation (de quelque façon qu’on la définisse fondée sur la rationalité. L’auteur de cet article examine tout d’abord le statut des contradictions et de l’impossible chez quelques théoriciens actuels (principalement J.-M. Schaeffer, M.-L. Ryan, L. Doležel et poéticiens du 16e siècle (L. Castelvetro et F. Patrizi. Sont ensuite étudiées la forme et la fonction que prend l’impossible dans trois fictions narratives de la Renaissance. L’hypothèse majeure qui est défendue est que ces paradoxes permettent de penser le non-existant, dans la continuité de la scolastique médiévale et en relation avec une problématique religieuse, sérieuse ou parodique. Par là même, et en raison de leur auto-référentialité constitutive, les paradoxes inscrivent dans la fiction une réflexion sur elle-même qui n’a rien d’une apologie. La pensée de la fiction s’articule en définitive de façon bien différente dans les théories et dans les fictions elles-mêmes.Like Renaissance poetics, contemporary theories of fiction do favour a conception of mimesis based on likelihood. In order to underscore the benefits of fiction, in terms of cognition or ethics, both ancient and present-day authors usually identify imitation (however this is understood as a kind of rationality. The aim of this article is to question the status of contradictions and impossibilities, first in current theories of fiction (J-M Schaeffer, M.-L. Ryan, L. Doležel, then in two sixteenth century comments of Aristotle (by L. Castelvetro and F. Patrizi. In the following steps, forms and functions of the impossible are studied in three narratives of the Renaissance. The main hypothesis here is the following: in

  3. Paradox in CSR Practice

    DEFF Research Database (Denmark)

    Rana, Mohammad Bakhtiar; Jokela, Paivi

    2017-01-01

    legitimacy. Balancing between the two goals depends on the nature of governance, management and organizational structure, which ensures its effectiveness in practice. We argue that ambidexterity is possible when firm’s ownership and management realizes CSR philosophy, which typically optimizes both social...... process because it would take into account the multiple stakeholders expectations. MNE subsidiary therefore should develop a governance mechanism that is compatible to the complex organizational and ownership structure across the global operations and supporting ROS mechanism. Developing compatible......Despite extensive corporate responsibility activities (CSR), MNE Subsidiaries often fail to meet stakeholders expectations; not only that they often violate laws, regulations, thus the paradoxical conditions arise from the simultaneous application of CSR and the violations of institutional...

  4. The Scenario Planning Paradox

    DEFF Research Database (Denmark)

    Spaniol, Matthew Jon; Rowland, Nicholas James

    2017-01-01

    planning paradox. Contributing fresh theory supposedly attends to the “dismal” state of theory, while contributing new typologies purportedly helps bring order to methodological chaos. Repeated over time, the contribution strategy breaks down. Effort to resolve the theoretical and methodological issue......, foundational theoretical perspective in futures studies. Perceived chaos gives way to typologies, which, as they mount, contribute to the chaos they were meant to resolve. The end result, intended by no one, is that theory remains dismal and methods remain chaotic. This direction for the field is indefensible......For more than a decade, futures studies scholars have prefaced scholarly contributions by repeating the claim that there is insufficient theory to support chaotic scenario methodology. The strategy is formulaic, and the net effect is a curious one, which the authors refer to as the scenario...

  5. MCM Paradox: Abundance of Eukaryotic Replicative Helicases and Genomic Integrity.

    Science.gov (United States)

    Das, Mitali; Singh, Sunita; Pradhan, Satyajit; Narayan, Gopeshwar

    2014-01-01

    As a crucial component of DNA replication licensing system, minichromosome maintenance (MCM) 2-7 complex acts as the eukaryotic DNA replicative helicase. The six related MCM proteins form a heterohexamer and bind with ORC, CDC6, and Cdt1 to form the prereplication complex. Although the MCMs are well known as replicative helicases, their overabundance and distribution patterns on chromatin present a paradox called the "MCM paradox." Several approaches had been taken to solve the MCM paradox and describe the purpose of excess MCMs distributed beyond the replication origins. Alternative functions of these MCMs rather than a helicase had also been proposed. This review focuses on several models and concepts generated to solve the MCM paradox coinciding with their helicase function and provides insight into the concept that excess MCMs are meant for licensing dormant origins as a backup during replication stress. Finally, we extend our view towards the effect of alteration of MCM level. Though an excess MCM constituent is needed for normal cells to withstand stress, there must be a delineation of the threshold level in normal and malignant cells. This review also outlooks the future prospects to better understand the MCM biology.

  6. Explaining the harmonic sequence paradox.

    Science.gov (United States)

    Schmidt, Ulrich; Zimper, Alexander

    2012-05-01

    According to the harmonic sequence paradox, an expected utility decision maker's willingness to pay for a gamble whose expected payoffs evolve according to the harmonic series is finite if and only if his marginal utility of additional income becomes zero for rather low payoff levels. Since the assumption of zero marginal utility is implausible for finite payoff levels, expected utility theory - as well as its standard generalizations such as cumulative prospect theory - are apparently unable to explain a finite willingness to pay. This paper presents first an experimental study of the harmonic sequence paradox. Additionally, it demonstrates that the theoretical argument of the harmonic sequence paradox only applies to time-patient decision makers, whereas the paradox is easily avoided if time-impatience is introduced. ©2011 The British Psychological Society.

  7. New paradoxes in intertemporal choice

    Directory of Open Access Journals (Sweden)

    Li-Lin Rao

    2011-02-01

    Full Text Available Similar to research on risky choice, the traditional analysis of intertemporal choice takes the view that an individual behaves so as to maximize the discounted sum of all future utilities. The well-known Allais paradox contradicts the fundamental postulates of maximizing the expected value or utility of a risky option. We describe a violation of the law of diminishing marginal utility as well as an intertemporal version of the Allais paradox.

  8. Consciousness and the "Causal Paradox"

    OpenAIRE

    Velmans, Max

    1996-01-01

    Viewed from a first-person perspective consciousness appears to be necessary for complex, novel human activity - but viewed from a third-person perspective consciousness appears to play no role in the activity of brains, producing a "causal paradox". To resolve this paradox one needs to distinguish consciousness of processing from consciousness accompanying processing or causing processing. Accounts of consciousness/brain causal interactions switch between first- and third-person perspectives...

  9. Paradoxical therapy in conversion disorder

    OpenAIRE

    ATAOĞLU, Ahmet

    1998-01-01

    Paradoxical therapy consists of suggesting that the patient intentionally engages in the unwanted behaviour, such as performing complusive ritual or bringing on a conversion attack. In this study paradoxical intention (PI) was used with to half of the patients with conversion disorders, while the other half were treated with diazepam in order to examine the efficiency of the PI versus diazepam in conversion disorder. Patients treated with PI appeared to have a greater improvement r...

  10. Paradoxes of Visibility

    Directory of Open Access Journals (Sweden)

    Tarnay László

    2017-12-01

    Full Text Available The paper investigates two possible critical arguments following the pictorial turn. The first is formulated within ocularcentrism, the dominance of sight, and starts with the right to visibility as a general principle that governs today’s digital culture but gets twisted in special cases like the Auschwitz photos of the Shoa, the Abu Ghraib prison videos, or recently the website called Yolocaust. The second is conceived outside the visual culture and is meant to vindicate the other senses vis-à-vis the eyes. However, the argument is truncated here only to highlight the boomerang effect of the other senses: haptic vision. It is the case of visual perception when (a there is a lack of things to see and (b indeterminate synaesthesia: when vision intensifies the other senses in the embodied viewer. The two arguments converge upon a dialectic of the visible and the imaginable, which is formulated here as two paradoxes that the discussed examples transcend. By enforcing visibility at all costs where there is hardly anything recognizable to see, they lead to two diverging results. On the one hand, the meaning of “image” is extended toward the unimaginable, the traumatic experience, on the other hand, it is extended toward the invisible, the encounter with the radical Other.

  11. Paradoxical consequences of prohibitions.

    Science.gov (United States)

    Sheikh, Sana; Janoff-Bulman, Ronnie

    2013-08-01

    Explanations based in attribution theory claim that strong external controls such as parental restrictiveness and punishment undermine moral internalization. In contrast, 3 studies provide evidence that parental punishment does socialize morality, but of a particular sort: a morality focused on prohibitions (i.e., proscriptive orientation) rather than positive obligations (i.e., prescriptive orientation). Study 1 found young adults' accounts of parental restrictiveness and punishment activated their sensitivity to prohibitions and predicted a proscriptive orientation. Consistent with the greater potency of temptations for proscriptively oriented children, as well as past research linking shame to proscriptive morality, Study 2 found that restrictive parenting was also associated with greater suppression of temptations. Finally, Studies 3A and 3B found that suppressing these immoral thoughts is paradoxically harder for those with strong proscriptive orientations; more specifically, priming a proscriptive (versus prescriptive) orientation and inducing mental suppression of "immoral" thoughts led to the most ego depletion for those with restrictive parents. Overall, individuals who had restrictive parents had the lowest self-regulatory ability to resist their "immoral" temptations after prohibitions were activated. In contrast to common attributional explanations, these studies suggest that harsh external control by parents does not undercut moral socialization but rather undermines individuals' ability to resist temptation.

  12. O paradoxo de Chalmers Chalmers' paradox

    Directory of Open Access Journals (Sweden)

    Gustavo Leal-Toledo

    2009-01-01

    Full Text Available O Argumento dos Zumbis proposto por Chalmers, ao contrário de defender o dualismo, bane as qualia para um "mundo" onde elas não podem influenciar o julgamento que fazemos sobre nós mesmos. Por este motivo, pelo próprio argumento, podemos ser um zumbi e não saber. A isso Chalmers chamou de The Paradox of Phenomenal Judgment. O problema é que ele aceita tal paradoxo como parte de sua própria teoria. No entanto, este movimento filosófico não é aceitável e este paradoxo mina a teoria de Chalmers por dentro mostrando que o argumento dos zumbis é, na verdade, um argumento contra o dualismo. Chalmers tenta resolver este problema com uma série de argumentos que tem como base o fato de que a consciência é um bruto explanandum indubitável. No entanto, tal tentativa fracassa por uma série de razões que mostram que mesmo se ele estivesse correto, ainda poderíamos ser um zumbi e não saber.The Zombie Argument proposed by Chalmers, instead of working as a defense of dualism, banishes qualia to a 'world' where they cannot influence our judgments about ourselves. For this reason, according to the argument itself, we may be all zombies and not know it. This is what Chalmers called The Paradox of Phenomenal Judgment. The problem is that he accepts this paradox as part of his theory. This philosophical move, however, is not acceptable, for the paradox undermines Chalmers' theory, by showing that the zombie argument is, actually, an argument against dualism. Chalmers tries to solve this problem with many arguments based on the status of consciousness as brute indubitable explanandum. However, this attempt is a failure by a series of reasons showing that, even if he were right, we could still be zombies and not know it.

  13. [The paradox of motherhood].

    Science.gov (United States)

    Ouaidou, N G

    1990-08-01

    All Sahelian countries are working to define their population policies. A population policy document avoids dispersion and duplication. It opens the path to efficiency. It makes it easier to achieve governmental socioeconomic objectives. Various recent population-related meetings have at least two points in common: they aim to overstep and improve a given situation and are at the same time some examples of implementing the Ndjamena action program, adopted in January 1989. All these population-centered actions return to the problem of adolescent fertility--a poignant problem. Adolescent pregnancy is a major source of family and social break-ups. This paradox of motherhood makes a violent storm burst in the skies ordinarily serene with joy and hope. It is an enemy perverse to economic development and social progress. Adolescent motherhood is a phenomenon which complicates and aggravates population problems and is taboo to the point it is still imperceptible, unknown. It is a problem of premier importance in the Sahel. Pregnancy strikes a woman so very unprepared for motherhood and its demands. It risks the life of a being which is preparing itself to enter the world. Adolescent pregnancy has equally tragic health effects: poorly performed underground abortions and maternal and infant deaths. Adolescent fertility is a burning problem regardless of the perspective (demographic, economic, social, or health). In Sahelian countries, one is beginning to be interested in and to speak about it. It will be necessary to search for solutions. Schools must be a top target for all activities aiming to check adolescent fertility. The emphasis must be on information, education, and responsibility of girls, boys, teachers, and parents. Education and training are of capital importance for socioeconomic development of the Sahel. All activities implemented in the education sector should include a large place for family life education in pregnancy prevention.

  14. The alien paradox.

    OpenAIRE

    Tugby, Matthew

    2015-01-01

    Platonism delivers a theory of possibility that is distinct from both Lewisian modal realism and ersatz modal theories. By putting the topic of alien properties at centre stage in our modal theorizing, a strong preliminary case for platonism can be made. A puzzle about alien properties is created by modern truthmaker theory and some plausible assumptions about properties and existence. But this puzzle is one that platonism is able to solve in a simple and conservative way.

  15. Mechanical Paradox: The Uphill Roller

    Science.gov (United States)

    Cortes, Emilio; Cortes-Poza, D.

    2011-01-01

    We analyse in detail the dynamics of a mechanical system which is a rigid body with the geometry of a double cone. This double cone is apparently able to spontaneously roll uphill along inclined rails. The experiment has been known for some centuries, and because of its peculiar behaviour, it has been named "mechanical paradox". Although this…

  16. The Paradox of Modern Suffering

    DEFF Research Database (Denmark)

    Dræby, Anders

    The Paradox of Suffering in modern western Culture In non-western cultures and pre-modern western cultures suffering is considered the normal state of life. Corrispondingly the suffering of oneself and that of other people form a central focus to most religions, their practices and philosophies...

  17. Teaching Quantum Physics without Paradoxes

    Science.gov (United States)

    Hobson, Art

    2007-01-01

    Although the resolution to the wave-particle paradox has been known for 80 years, it is seldom presented. Briefly, the resolution is that material particles and photons are the quanta of extended spatially continuous but energetically quantized fields. But because the resolution resides in quantum field theory and is not usually spelled out in…

  18. The Banach-Tarski paradox

    CERN Document Server

    Wagon, Stan

    1985-01-01

    The Banach-Tarski paradox is a most striking mathematical construction: it asserts that a solid ball may be taken apart into finitely many pieces that can be rearranged using rigid motions to form a ball twice as large as the original. This volume explore

  19. The Paradox of Painful Art

    Science.gov (United States)

    Smuts, Aaron

    2007-01-01

    Many of the most popular genres of narrative art are designed to elicit negative emotions: emotions that are experienced as painful or involving some degree of pain, which people generally avoid in their daily lives. Traditionally, the question of why people seek out such experiences of painful art has been presented as the paradox of tragedy, and…

  20. On Johnson's Paradox: Hypothesis Verification

    Science.gov (United States)

    Noble, Clyde E.

    1975-01-01

    When H. M. Johnson argued that all inductive reasoning is based on the fallacy of affirming the consequent and cannot therefore establish the 'truth' of scientific hypotheses, he posed a paradox for strict empiricists. Author examined Johnson's argument. (Editor/RK)

  1. On the regularization of impact without collision: the Painlevé paradox and compliance

    DEFF Research Database (Denmark)

    Hogan, S. J.; Kristiansen, K. Uldall

    2017-01-01

    approach, we recover impact without collision (IWC) in both the inconsistent and the indeterminate Painlevéé paradoxes, in the latter case giving an exact formula for conditions that separate IWC and lift-off. We solve the problem for arbitrary values of the compliance damping and give explicit...

  2. The nature of quantum paradoxes

    International Nuclear Information System (INIS)

    Tarozzi, G.; Van der Merwe, A.

    1988-01-01

    The nature of Quantum Paradoxes provides an exhaustive general view of the most recent studies and research carried out by Italian scientists and philosophers of science in the field of the foundations of quantum physics, employing a critical stance and an alternative to the orthodox Copenhagen interpretation. During the last twenty years the Italians have produced a remarkable amount of work on the quantum-mechanical theory of measurement, the interpretation of the wave-function, the axiomatization of quantum formalism, Bell-type theorems and realistic local theories, thus creating one of the most advanced contributions to the problems of understanding Nature and clarifying the origin of the quantum paradoxes. (author). refs.; figs.; tabs

  3. Klein paradox and vacuum polarization

    International Nuclear Information System (INIS)

    Damour, T.

    1977-01-01

    This contribution reviews some of the methods which can be used when studying quantum fields in a given stationary classical external field. The attention is mainly directed towards cases where real pair creation can occur in such a stationary background. The paradigm of this situation is the Klein paradox. This paradox is best approached by the introduction of some energy diagrams whose direct extension to black holes physics has proven to be very useful. Finally processes of real pair creation around a Kerr-Newman (charged and rotating) black hole and their feedback on the geometry are briefly discussed. It is also shown how the Hawking process can be recovered in this approach. (Auth.)

  4. Illustrations of the twin paradox

    International Nuclear Information System (INIS)

    Rebhan, E.

    1985-01-01

    In order to provide a more intuitive understanding of the twin paradox, several illustrations of this are presented. In one of these, each of the twins is equipped with a lamp whose monochromatic light can be observed by the other. In other illustrations the travelling twin uses an Einstein train instead of a space ship, all the cars of the train and all stations along the route of the train being equipped with clocks. (author)

  5. Mechanical paradox: the uphill roller

    International Nuclear Information System (INIS)

    Cortes, Emilio; Cortes-Poza, D

    2011-01-01

    We analyse in detail the dynamics of a mechanical system which is a rigid body with the geometry of a double cone. This double cone is apparently able to spontaneously roll uphill along inclined rails. The experiment has been known for some centuries, and because of its peculiar behaviour, it has been named 'mechanical paradox'. Although this instrument is well known today, we have not found in the literature a dynamical study like the one we are presenting. A deeper analysis of this mechanical object will allow us to go further than explaining the apparent paradox in the system; it will show interesting features of the dynamics that are not evident or intuitive. In this work, we follow a complete study of the geometry, the kinematic variables and the Lagrangian dynamics of the problem for any set of the angular parameters and initial values, and obtain as a result a full description of the dynamic variables of this mechanical device. In addition to studying the dynamics of the system with the angles that yield the typical paradoxical behaviour, we study carefully what we call the constant potential geometry regime, where the centre of mass maintains its height, and found in this particular case some features of the dynamics which are not common in rolling objects. We believe that this work can offer the student good material to review some fundamental concepts of analytical mechanics.

  6. Reinterpretaion of the friendship paradox

    Science.gov (United States)

    Fu, Jingcheng; Wu, Jianliang

    The friendship paradox (FP) is a sociological phenomenon stating that most people have fewer friends than their friends do. It is to say that in a social network, the number of friends that most individuals have is smaller than the average number of friends of friends. This has been verified by Feld. We call this interpreting method mean value version. But is it the best choice to portray the paradox? In this paper, we propose a probability method to reinterpret this paradox, and we illustrate that the explanation using our method is more persuasive. An individual satisfies the FP if his (her) randomly chosen friend has more friends than him (her) with probability not less than 1/2. Comparing the ratios of nodes satisfying the FP in networks, rp, we can see that the probability version is stronger than the mean value version in real networks both online and offline. We also show some results about the effects of several parameters on rp in random network models. Most importantly, rp is a quadratic polynomial of the power law exponent γ in Price model, and rp is higher when the average clustering coefficient is between 0.4 and 0.5 in Petter-Beom (PB) model. The introduction of the probability method to FP can shed light on understanding the network structure in complex networks especially in social networks.

  7. Multisetting Greenberger-Horne-Zeilinger paradoxes

    Science.gov (United States)

    Tang, Weidong; Yu, Sixia; Oh, C. H.

    2017-01-01

    The Greenberger-Horne-Zeilinger (GHZ) paradox provides an all-versus-nothing test for the quantum nonlocality. In most of the GHZ paradoxes known so far each observer is allowed to measure only two alternative observables. Here we present a general construction for GHZ paradoxes in which each observer measures more than two observables given that the system is prepared in the n -qudit GHZ state. By doing so we are able to construct a multisetting GHZ paradox for the n -qubit GHZ state, with n being arbitrary, which is genuine n -partite; i.e., no GHZ paradox exists when restricted to a subset of a number of observers for a given set of Mermin observables. Our result fills up the gap of the absence of a genuine GHZ paradox for the GHZ state of an even number of qubits, especially the four-qubit GHZ state as used in GHZ's original proposal.

  8. The three-box paradox revisited

    International Nuclear Information System (INIS)

    Ravon, Tamar; Vaidman, Lev

    2007-01-01

    The classical three-box paradox of Kirkpatrick (2003 J. Phys. A: Math. Gen. 36 4891) is compared to the original quantum three-box paradox of Aharonov and Vaidman (1991 J. Phys. A: Math. Gen. 24 2315). It is argued that the quantum three-box experiment is a 'quantum paradox' in the sense that it is an example of a classical task which cannot be accomplished using classical means, but can be accomplished using quantum devices. It is shown that Kirkpatrick's card game is analogous to a different game with a particle in three boxes which does not contain paradoxical features

  9. Salt disposal: Paradox Basin, Utah

    International Nuclear Information System (INIS)

    1983-04-01

    This report presents the findings of a study conducted for the National Waste Terminal Storage (NWTS) Program. Permanent disposal options are examined for salt resulting from the excavation of a waste repository in the bedded salt deposits of the Paradox Basin of southeastern Utah. The study is based on a repository salt backfill compaction of 60% of the original density which leaves a total of 8 million tons of 95% pure salt to be disposed of over a 30-year period. The feasibility, impacts, and mitigation methods are examined for five options: commercial disposal, permanent onsite surface disposal, permanent offsite disposal, deepwell injection, and ocean and Great Salt Lake disposal. The study concludes the following: Commercial marketing of all repository salt would require a subsidy for transportation to major salt markets. Permanent onsite surface storage is both economically and technically feasible. Permanent offsite disposal is technically feasible but would incur additional transportation costs. Selection of an offsite location would provide a means of mitigating impacts associated with surface storage at the repository site. Deepwell injection is an attractive disposal method; however, the large water requirement, high cost of development, and poor performance of similar operating brine disposal wells eliminates this option from consideration as the primary means of disposal for the Paradox Basin. Ocean disposal is expensive because of high transportation cost. Also, regulatory approval is unlikely. Ocean disposal should be eliminated from further consideration in the Paradox Basin. Great Salt Lake disposal appears to be technically feasible. Great Salt Lake disposal would require state approval and would incur substantial costs for salt transportation. Permanent onsite disposal is the least expensive method for disposal of all repository salt

  10. The MedDRA paradox.

    Science.gov (United States)

    Merrill, Gary H

    2008-11-06

    MedDRA (the Medical Dictionary for Regulatory Activities Terminology) is a controlled vocabulary widely used as a medical coding scheme. However, MedDRA's characterization of its structural hierarchy exhibits some confusing and paradoxical features. The goal of this paper is to examine these features, determine whether there is a coherent view of the MedDRA hierarchy that emerges, and explore what lessons are to be learned from this for using MedDRA and similar terminologies in a broad medical informatics context that includes relations among multiple disparate terminologies, thesauri, and ontologies.

  11. A Note on Faraday Paradoxes

    CERN Document Server

    Auchmann, Bernhard; Russenschuck, Stephan

    2014-01-01

    The validity of the flux rule to determine the electromotive force in a cycle, epsilon = -d Phi/dt, has been the subject of a large amount of controversy since the beginning of electrical technology. Although most authors reach correct conclusions for a class of problems called Faraday paradoxes, the arguments that are used vary and often rely on ad-hoc physical reasoning. A didactic and insightful treatment should be based solely on Maxwell's equations, the constitutive laws, and a detailed study of the mathematics involved.

  12. A Krein quantization approach to Klein paradox

    International Nuclear Information System (INIS)

    Payandeh, Farrin; Fathi, Mohsen; Mohammad Pur, Toradj; Moghaddam, Zahra Gh.

    2013-01-01

    In this paper we first introduce the famous Klein paradox. Afterwards by proposing the Krein quantization approach and taking the negative modes into account, we will show that the expected and exact current densities could be achieved without confronting any paradox. (authors)

  13. The clock paradox as a cosmological problem

    International Nuclear Information System (INIS)

    Fu, K.Y.

    1975-01-01

    In this paper the clock paradox is discussed within the framework of the general theory of relativity. It is shown that in general the aging asymmetry exists. It is also argued that the clock paradox, according to Mach's principle, is essentially a cosmological problem. (author)

  14. Negative freedom and the liberal paradoxes

    NARCIS (Netherlands)

    van Hees, M.V.B.P.M

    In their game-theoretic formulations, the liberal paradoxes of Amartya Sm and Alan Gibbard show a tension between freedom on the one hand, and Pareto optimality and stability on the other. This article examines what happens to the liberal paradoxes if a negative conception of freedom is used. Given

  15. Quantum Zeno and anti-Zeno paradoxes

    Indian Academy of Sciences (India)

    Abstract. Continuous observation of a time independent projection operator is known to prevent change of state (the quantum Zeno paradox). We discuss the recent result that generic continuous measurement of time dependent projection operators will in fact ensure change of state: an anti-Zeno paradox.

  16. Family Fathers Lost in Theatre Paradox

    DEFF Research Database (Denmark)

    Kuhlmann, Annelis

    2008-01-01

    Diderot's influence on theatre is well known through The Paradox of Acting (Paradoxe sur le comédien). However, Diderot also wrote a few drames bourgeois, among which is The Family Father (Le Père de famille), which still in Diderot's days was edited in Copenhagen in French, and which in Danish...

  17. A Paradoxical Approach to Vocational Indecision.

    Science.gov (United States)

    Lopez, Frederick G.

    1983-01-01

    Describes a case study in which a paradoxical intervention was effectively used in treating a vocationally indecisive college student and his overly involved father. The quality of the father-son interaction improved as the student's anxiety decreased. Implications for the use of paradox in other situations are discussed. (Author/JAC)

  18. Virtue Acquisition: The Paradox of Striving

    Science.gov (United States)

    Snow, Nancy

    2016-01-01

    Aristotelian-inspired accounts of virtue acquisition stress guided practice and habituated action to develop virtue. This emphasis on action can lead to the "paradox of striving". The paradox occurs when we try too hard to act well and thereby spoil our efforts. I identify four forms of striving--forcing, impulsivity, overthinking, and…

  19. New Paradoxes of Risky Decision Making

    Science.gov (United States)

    Birnbaum, Michael H.

    2008-01-01

    During the last 25 years, prospect theory and its successor, cumulative prospect theory, replaced expected utility as the dominant descriptive theories of risky decision making. Although these models account for the original Allais paradoxes, 11 new paradoxes show where prospect theories lead to self-contradiction or systematic false predictions.…

  20. Yule-Simpson's Paradox in Research

    Science.gov (United States)

    Goltz, Heather Honore; Smith, Matthew Lee

    2010-01-01

    Yule (1903) and Simpson (1951) described a statistical paradox that occurs when data is aggregated. In such situations, aggregated data may reveal a trend that directly contrasts those of sub-groups trends. In fact, the aggregate data trends may even be opposite in direction of sub-group trends. To reveal Yule-Simpson's paradox (YSP)-type…

  1. Contralateral paradoxical response to chemotherapy in tuberculous ...

    African Journals Online (AJOL)

    Pleural effusions may occur as a complication of primary tuberculosis or an established pulmonary or extrapulmonary infection. New formation or expansion of a tuberculous lesion during chemotherapy is referred to as paradoxical response. Paradoxical response has been described to occur weeks or months after starting ...

  2. [Five paradoxes in health promotion].

    Science.gov (United States)

    López-Dicastillo, Olga; Canga-Armayor, Navidad; Mujika, Agurtzane; Pardavila-Belio, Miren Idoia; Belintxon, Maider; Serrano-Monzó, Inmaculada; Pumar-Méndez, María J

    The World Health Organization states that health promotion is a key strategy to improve health, and it is conceived as a global process of enabling people to increase control over, and to improve, their health. Health promotion does not focus solely on empowering individuals dealing with their knowledge, attitudes and skills, but it also takes political, social, economic and environmental aspects influencing health and wellbeing into account. The complexity of applying these concepts is reflected in the five paradoxes in health promotion; these arise in between the rhetoric in health promotion and implementation. The detected paradoxes which are described herein involve the patient versus the person, the individual versus the group, disease professionals versus health professionals, disease indicators versus health indicators, and health as an expense versus health as an investment. Making these contradictions explicit can help determine why it is so complex to put the concepts related to health promotion into practice. It can also help to put forward aspects that need further work if health promotion is to put into practice. Copyright © 2017 SESPAS. Publicado por Elsevier España, S.L.U. All rights reserved.

  3. Parrondo’s paradox for chaos control and anticontrol of fractional-order systems

    International Nuclear Information System (INIS)

    Danca, Marius-F; Tang, Wallace K S

    2016-01-01

    We present the generalized forms of Parrondo’s paradox existing in fractional-order nonlinear systems. The generalization is implemented by applying a parameter switching (PS) algorithm to the corresponding initial value problems associated with the fractional-order nonlinear systems. The PS algorithm switches a system parameter within a specific set of N ≥ 2 values when solving the system with some numerical integration method. It is proven that any attractor of the concerned system can be approximated numerically. By replacing the words “winning” and “loosing” in the classical Parrondo’s paradox with “order” and “chaos', respectively, the PS algorithm leads to the generalized Parrondo’s paradox: chaos 1 + chaos 2 + ··· + chaos N = order and order 1 + order 2 + ··· + order N = chaos. Finally, the concept is well demonstrated with the results based on the fractional-order Chen system. (paper)

  4. Paradoxical Behavior of Granger Causality

    Science.gov (United States)

    Witt, Annette; Battaglia, Demian; Gail, Alexander

    2013-03-01

    Granger causality is a standard tool for the description of directed interaction of network components and is popular in many scientific fields including econometrics, neuroscience and climate science. For time series that can be modeled as bivariate auto-regressive processes we analytically derive an expression for spectrally decomposed Granger Causality (SDGC) and show that this quantity depends only on two out of four groups of model parameters. Then we present examples of such processes whose SDGC expose paradoxical behavior in the sense that causality is high for frequency ranges with low spectral power. For avoiding misinterpretations of Granger causality analysis we propose to complement it by partial spectral analysis. Our findings are illustrated by an example from brain electrophysiology. Finally, we draw implications for the conventional definition of Granger causality. Bernstein Center for Computational Neuroscience Goettingen

  5. The paradox of atheoretical classification

    DEFF Research Database (Denmark)

    Hjørland, Birger

    2016-01-01

    A distinction can be made between “artificial classifications” and “natural classifications,” where artificial classifications may adequately serve some limited purposes, but natural classifications are overall most fruitful by allowing inference and thus many different purposes. There is strong...... support for the view that a natural classification should be based on a theory (and, of course, that the most fruitful theory provides the most fruitful classification). Nevertheless, atheoretical (or “descriptive”) classifications are often produced. Paradoxically, atheoretical classifications may...... be very successful. The best example of a successful “atheoretical” classification is probably the prestigious Diagnostic and Statistical Manual of Mental Disorders (DSM) since its third edition from 1980. Based on such successes one may ask: Should the claim that classifications ideally are natural...

  6. Paradoxes unbounded: Practising community making

    Directory of Open Access Journals (Sweden)

    Tess Maginess

    2011-10-01

    Full Text Available The first section of this paper is a discussion of the paradoxes contained in definitionsof the word 'community' and deliberately foregrounds and makes problematicconflicting meanings before arguing for a third definition and practice of community.This third definition and practice celebrates and even transcends contradictions withinan active learning model of education in the community, aimed at tackling inequalityand prejudice. The second section offers an autocritical narrative account of aneducation in the community project that illustrates how such a practice of communitymaking can be achieved within an educational framework in which pupil is teacher andteacher is pupil and in which an imaginative, creative approach is deployed toconstruct a community making practice. The paper draws on understandings fromcommunity development, inclusive and creative education, emancipatory actionresearch, postcolonial and post-structuralist theory.

  7. Conjunct rotation: Codman's paradox revisited.

    Science.gov (United States)

    Wolf, Sebastian I; Fradet, Laetitia; Rettig, Oliver

    2009-05-01

    This contribution mathematically formalizes Codman's idea of conjunct rotation, a term he used in 1934 to describe a paradoxical phenomenon arising from a closed-loop arm movement. Real (axial) rotation is distinguished from conjunct rotation. For characterizing the latter, the idea of reference vector fields is developed to define the neutral axial position of the humerus for any given orientation of its long axis. This concept largely avoids typical coordinate singularities arising from decomposition of 3D joint motion and therefore can be used for postural (axial) assessment of the shoulder joint both clinically and in sports science in almost the complete accessible range of motion. The concept, even though algebraic rather complex, might help to get an easier and more intuitive understanding of axial rotation of the shoulder in complex movements present in daily life and in sports.

  8. Tachyon kinematics and causality: a systematic thorough analysis of the tachyon causal paradoxes

    International Nuclear Information System (INIS)

    Recami, E.

    1987-01-01

    The chronological order of the events along a spacelike path is not invariant under Lorentz transformations, as is well known. This led to an early conviction that tachyons would give rise to causal anomalies. A relativistic version of the Stueckelberg-Feynman switching procedure (SWP) has been invoked as the suitable tool to eliminate those anomalies. The application of the SWP does eliminate the motions backwards in time, but interchanges the roles of source and detector. This fact triggered the proposal of a host of causal paradoxes. Till now, however, it has not been recognized that such paradoxes can be sensibly discussed (and completely solved, at least in microphysics) only after the tachyon relativistic mechanics has been properly developed. They start by showing how to apply the SWP, both in the case of ordinary special relativity and in the case with tachyons. Then they carefully exploit the kinetics of the tachyon exchange between two (ordinary) bodies. Being finally able to tackle the tachyon causality problem, they successively solve the paradoxes of: (i) Tolman-Regge, (ii) Pirani, (iii) Edmonds, and (iv) Bell. Finally, they discuss a further, new paradox associated with the transmission of signals by modulated tachyon beams

  9. Paradoxical aortic stenosis: A systematic review.

    Science.gov (United States)

    Cavaca, Rita; Teixeira, Rogério; Vieira, Maria João; Gonçalves, Lino

    2017-04-01

    Aortic stenosis (AS) is a complex systemic valvular and vascular disease with a high prevalence in developed countries. The new entity "paradoxical low-flow, low-gradient aortic stenosis" refers to cases in which patients have severe AS based on assessment of aortic valve area (AVA) (≤1 cm 2 ) or indexed AVA (≤0.6 cm 2 /m 2 ), but paradoxically have a low mean transvalvular gradient (<40 mmHg) and a low stroke volume index (≤35 ml/m 2 ), despite preserved left ventricular ejection fraction (≥50%). A search was carried out in the PubMed database on paradoxical AS for the period 2007-2014. A total of 57 articles were included for this review. The prevalence of paradoxical AS ranged from 3% to 35% of the population with severe degenerative AS. It was more frequent in females and in older patients. Paradoxical AS was associated with characteristic left ventricular remodeling as well as an increase in systemic arterial stiffness. It was noted that there may be errors and inaccuracies in the calculation of AVA by the continuity equation, which could erroneously suggest the paradoxical phenotype. There are new diagnostic methods to facilitate the study of AS, such as aortic valve calcium score, valvuloarterial impedance and the longitudinal mechanics of the left ventricle. With regard to its natural history, it is not clear whether paradoxical AS corresponds to an advance stage of the disease or if paradoxical AS patients have a distinct phenotype with specific characteristics. Valve replacement, either surgical or percutaneous, may be indicated in patients with severe and symptomatic paradoxical AS. Copyright © 2016 Sociedade Portuguesa de Cardiologia. Publicado por Elsevier España, S.L.U. All rights reserved.

  10. Optical tweezers and paradoxes in electromagnetism

    International Nuclear Information System (INIS)

    Pfeifer, Robert N C; Nieminen, Timo A; Heckenberg, Norman R; Rubinsztein-Dunlop, Halina

    2011-01-01

    The widespread application of optical forces and torques has contributed to renewed interest in the fundamentals of the electromagnetic force and torque, including long-standing paradoxes such as the Abraham–Minkowski controversy and the angular momentum density of a circularly polarized plane wave. We discuss the relationship between these electromagnetic paradoxes and optical tweezers. In particular, consideration of possible optical tweezers experiments to attempt to resolve these paradoxes strongly suggests that they are beyond experimental resolution, yielding identical observable results in all cases

  11. Bosonic analog of the Klein paradox

    International Nuclear Information System (INIS)

    Wagner, R. E.; Ware, M. R.; Su, Q.; Grobe, R.

    2010-01-01

    The standard Klein paradox describes how an incoming electron scatters off a supercritical electrostatic barrier that is so strong that it can generate electron-positron pairs. This fermionic system has been widely discussed in textbooks to illustrate some of the discrepancies between quantum mechanical and quantum field theoretical descriptions for the pair creation process. We compare the fermionic dynamics with that of the corresponding bosonic system. We point out that the direct counterpart of the Pauli exclusion principle (the central mechanism to resolve the fermionic Klein paradox) is stimulated emission, which leads to the resolution of the analogous bosonic paradox.

  12. Second Parrondo's Paradox in Scale Free Networks

    OpenAIRE

    Toyota, Norihito

    2012-01-01

    Parrondo's paradox occurs in sequences of games in which a winning expectation value of a payoff may be obtained by playing two games in a random order, even though each game in the sequence may be lost when played individually.Several variations of Parrondo's games apparently with the same paradoxical property have been introduced by G.P. Harmer and D. Abbott; history dependence, one dimensional line, two dimensional lattice and so on. I have shown that Parrondo's paradox does not occur in s...

  13. The Merger Paradox and R&D

    OpenAIRE

    MIYAGIWA, Kaz; WAN, Jiangyun(Yunyun)

    2015-01-01

    The merger paradox is revisited in the presence of cost-reducing R&D in Cournot oligopoly. Two cases are found, in which merger is profitable without satisfying the 80-percent threshold requirement of Salant et al (1983).

  14. New loophole for the EPR paradox

    OpenAIRE

    Feldmann, Michel

    1999-01-01

    We exhibit a classical model free from any paradox which exactly simulates the spin EPR test. We conclude that Bell's inequality violation is a strictly classical phenomenon, contrary to a general belief.

  15. six six six paradox : [luuletused] / Triin Tasuja

    Index Scriptorium Estoniae

    Tasuja, Triin

    2008-01-01

    Sisu: six six six paradox ; cat stevens ; "vahel tundub, et mu ümber..." ; sääse ; Salaalaealised ; kolkalapsed ; longin mööda lumiseid tänavaid ; punkrock dekadents ; "Igast kirjaneitsist..." ; "mina olengi see saikochick..."

  16. Corporal punishment contestations, paradoxes and implications for ...

    African Journals Online (AJOL)

    Corporal punishment contestations, paradoxes and implications for school leadership: A case study of two South African high schools. ... South African Journal of Education. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current ...

  17. Spin entanglement, decoherence and Bohm's EPR paradox

    OpenAIRE

    Cavalcanti, E. G.; Drummond, P. D.; Bachor, H. A.; Reid, M. D.

    2007-01-01

    We obtain criteria for entanglement and the EPR paradox for spin-entangled particles and analyse the effects of decoherence caused by absorption and state purity errors. For a two qubit photonic state, entanglement can occur for all transmission efficiencies. In this case, the state preparation purity must be above a threshold value. However, Bohm's spin EPR paradox can be achieved only above a critical level of loss. We calculate a required efficiency of 58%, which appears achievable with cu...

  18. A Resolution of the Paradox of Enrichment

    OpenAIRE

    Feng, Z. C.; Li, Y. Charles

    2011-01-01

    The paradox of enrichment was observed by M. Rosenzweig in a class of predator-prey models. Two of the parameters in the models are crucial for the paradox. These two parameters are the prey's carrying capacity and prey's half-saturation for predation. Intuitively, increasing the carrying capacity due to enrichment of the prey's environment should lead to a more stable predator-prey system. Analytically, it turns out that increasing the carrying capacity always leads to an unstable predator-p...

  19. [Once again about "Gregg paradox" and its solution].

    Science.gov (United States)

    Mavrodiev, E V

    2002-01-01

    "Gregg paradox" means that monotypical groups containing the same species (or groups of species) will be equal each other although systematics considers them as different taxa. Thus if the order of placental mammalia Tubilidentata includes one species aardvark Orycteropus after, the order itself, its single family Orycteropodiaceae, single genus of the family Orycteropus and the single species Orycteropus after can be considered as equal to each other. To solve this disagreement the author asserts that taxa of any level can be regarded as an individual according to the taxa of higher rank. Possibility of such interpretation was already suggested by Georg Cantor (1985). He supposed that a set (class) can be regarded as unity by itself. In this case connections between taxa of different levels can be realized by Peano ratio of intrasitive conformities. In this model a genus will consist of species but not individuals, a type--of classes, etc. Thus, if a taxon x as an individual is an element of taxon y, and taxon y as an individual is an element of taxon z, then z according to x will be not only logical class, but class of classes and, hence we could not consider x as an element of z, because the latter consists of indecomposable individual-class y or some similar classes. In this situation "Gregg paradox" does not arise.

  20. The Paradox of Isochrony in the Evolution of Human Rhythm

    Directory of Open Access Journals (Sweden)

    Andrea Ravignani

    2017-11-01

    Full Text Available Isochrony is crucial to the rhythm of human music. Some neural, behavioral and anatomical traits underlying rhythm perception and production are shared with a broad range of species. These may either have a common evolutionary origin, or have evolved into similar traits under different evolutionary pressures. Other traits underlying rhythm are rare across species, only found in humans and few other animals. Isochrony, or stable periodicity, is common to most human music, but isochronous behaviors are also found in many species. It appears paradoxical that humans are particularly good at producing and perceiving isochronous patterns, although this ability does not conceivably confer any evolutionary advantage to modern humans. This article will attempt to solve this conundrum. To this end, we define the concept of isochrony from the present functional perspective of physiology, cognitive neuroscience, signal processing, and interactive behavior, and review available evidence on isochrony in the signals of humans and other animals. We then attempt to resolve the paradox of isochrony by expanding an evolutionary hypothesis about the function that isochronous behavior may have had in early hominids. Finally, we propose avenues for empirical research to examine this hypothesis and to understand the evolutionary origin of isochrony in general.

  1. The Paradox of Equal Opportunities

    Directory of Open Access Journals (Sweden)

    Mitja Sardoč

    2014-06-01

    Full Text Available The basic assumption of the idea of equal opportunities is based on the assertion that all individuals competing for an advantaged social position should have equal opportunities, i.e., that each and every one of them should have fair opportunities to achieve a particular goal. Despite the fact that equal opportunities is one of the basic mechanisms for a just distribution of advantageous social positions, the idea of fair equality of opportunity remains divided between different competing political projects, e.g., egalitarian liberalism, libertarian political theory, multiculturalism, etc. This paper examines two basic dimensions of equal opportunities to which existing conceptions fail to offer a unanimous answer, i.e., a the issue of fairness and b the issue of the currency of fairness. The concluding part of this paper presents two basic paradoxes that determine both the direction of the discussion as well as the possible solutions to the achievement of fair equal opportunities as part of any process for competing for advantageous social positions.

  2. Unveiling the Mobile Learning Paradox.

    Science.gov (United States)

    Mather, Carey; Cummings, Elizabeth

    2015-01-01

    A mobile learning paradox exists in Australian healthcare settings. Although it is increasingly acknowledged that timely, easy, and convenient access to health information using mobile learning technologies can enhance care and improve patient outcomes, currently there is an inability for nurses to access information at the point of care. Rapid growth in the use of mobile technology has created challenges for learning and teaching in the workplace. Easy access to educational resources via mobile devices challenges traditional strategies of knowledge and skill acquisition. Redesign of learning and teaching in the undergraduate curriculum and the development of policies to support the use of mobile learning at point of care is overdue. This study explored mobile learning opportunities used by clinical supervisors in tertiary and community-based facilities in two Australian States. Individual, organisation and systems level governance were sub-themes of professionalism that emerged as the main theme and impacts on learning and teaching in situ in healthcare environments. It is imperative healthcare work redesign includes learning and teaching that supports professional identity formation of students during work integrated learning.

  3. The obesity paradox and osteoporosis.

    Science.gov (United States)

    Fassio, Angelo; Idolazzi, Luca; Rossini, Maurizio; Gatti, Davide; Adami, Giovanni; Giollo, Alessandro; Viapiana, Ombretta

    2018-06-01

    Overweight and obesity according to the definition of the WHO are considered as an abnormal or excessive fat accumulation that may impair health. Studies comparing fracture incidence in obese and non-obese individuals have demonstrated that obesity, defined on the basis of body mass index (BMI), is associated with increased risk of fracture at some sites but seems to be protective at others. The results of the studies are influenced by the distribution of BMI in the population studied; for example, in cohorts with a low prevalence of obesity, a predilection for certain fracture sites in obese individuals becomes difficult to detect, whereas, in populations with a high prevalence of obesity, previously unreported associations may emerge. Furthermore, obesity can bring with itself many complications (Type 2 diabetes mellitus, vitamin D deficiency, and motor disability) which, in the long run, can have a definite influence in terms of overall risk and quality of life, as well. This is a narrative review focusing on the relationship between bone metabolism and overweight/obesity and dealing with the fundamental dilemma of a disease (obesity) apparently associated with improved values of bone mineral density, part of a complicated relationship which revolves around obesity called "the obesity paradox".

  4. Antiparticle in Light of Einstein-Podolsky-Rosen Paradox and Klein Paradox

    OpenAIRE

    Ni, Guang-jiong; Guan, Hong; Zhou, Weimin; Yan, Jun

    2000-01-01

    The original version of Einstein-Podolsky-Rosen (EPR) paradox and the Klein paradox of Klein-Gordon (KG) equation are discussed to show the necessity of existence of antiparticle with its wavefunction being fixed unambiguously. No concept of "hole" is needed.

  5. Use of informed consent with therapeutic paradox.

    Science.gov (United States)

    Farkas, M M

    1992-01-01

    Debate persists in the literature and among clinicians about the ethical appropriateness of paradoxical interventions. It has been suggested that informed consent with therapeutic paradox would alleviate ethical concerns of deception, manipulation, harm to the client, and withholding of information from the client in therapy. The purpose of this study was to explore health care consumer reactions to the benefits and risks of therapeutic paradox as stated in a consent for treatment form. The study explored the responses of 32 medical patients to a hypothetical consent for treatment form for therapeutic paradox. Data were collected in a brief semistructured interview after subjects read the hypothetical consent form. Utilizing a case study, the investigator then offered an example of a successful paradoxical intervention and additional subject comments were solicited. Content analysis of the responses was made. Health care consumers had mixed responses to the consent form. While the consent form served as an obstacle for some consumers, many were willing to sign the consent form and accept treatment even though they had internal reservations and questions. Appropriateness of the consent form format is discussed.

  6. Three Paradoxes of the Future Prediction

    Directory of Open Access Journals (Sweden)

    D. V. Pivovarov

    2012-01-01

    Full Text Available The paper is devoted to the issue of predicting the future. While creating the future image of the mankind as a whole, and Russia in particular, extrapolated some 50 or 100 years ahead, such cultural forms as religion, philosophy, education and art make their significant impact. However, philosophy plays a special role of critical methodology in coordinating the futurological efforts. It works as a tuning fork that tunes up the orchestra of various sciences and other forms of social consciousness. Being dialectical, philosophers find out and analyze the contradictions – paradoxes, antinomies, and aporias - involved in such activities as prophesizing, prognosticating, predicting and foreseeing. On the basis of the retrospective analysis, the author considers the most significant paradoxes facing the futurologists engaged in predicting the general course of historic events; the paradoxes being denoted as follows: the antinomy of academic ignorance, paradox of newness and paradox of an emergent effect. The analysis results in conclusion that the large-scale, long-term «scientific predictions of the future», claiming to be the truth and pretending for historical value and accuracy, are impossible or at least doubtful. Nevertheless, global prognoses are highly valued, widely discussed and always in demand in society due to the purposeful human intellect. 

  7. Three Paradoxes of the Future Prediction

    Directory of Open Access Journals (Sweden)

    D. V. Pivovarov

    2015-02-01

    Full Text Available The paper is devoted to the issue of predicting the future. While creating the future image of the mankind as a whole, and Russia in particular, extrapolated some 50 or 100 years ahead, such cultural forms as religion, philosophy, education and art make their significant impact. However, philosophy plays a special role of critical methodology in coordinating the futurological efforts. It works as a tuning fork that tunes up the orchestra of various sciences and other forms of social consciousness. Being dialectical, philosophers find out and analyze the contradictions – paradoxes, antinomies, and aporias - involved in such activities as prophesizing, prognosticating, predicting and foreseeing. On the basis of the retrospective analysis, the author considers the most significant paradoxes facing the futurologists engaged in predicting the general course of historic events; the paradoxes being denoted as follows: the antinomy of academic ignorance, paradox of newness and paradox of an emergent effect. The analysis results in conclusion that the large-scale, long-term «scientific predictions of the future», claiming to be the truth and pretending for historical value and accuracy, are impossible or at least doubtful. Nevertheless, global prognoses are highly valued, widely discussed and always in demand in society due to the purposeful human intellect. 

  8. The broiler breeder paradox: ethical, genetic and physiological perspectives, and suggestions for solutions.

    Science.gov (United States)

    Decuypere, E; Bruggeman, V; Everaert, N; Li, Yue; Boonen, R; De Tavernier, J; Janssens, S; Buys, N

    2010-10-01

    1. Due to intensive selection, broiler chickens became the most efficient meat-producing animals because of their fast growth, supported by a virtually unlimited voluntary feed intake. These characteristics cause many problems in the management of broiler breeder hens because of the negative correlation between muscle growth and reproduction effectiveness. 2. This problem, namely the fast muscle growth versus reproduction health paradox, induces a second paradox, acceptable reproduction and health versus hunger stress and impaired welfare, because broiler breeder hens require dedicated programmes of feed restriction (1) to maximise egg and chick production and (2) to avoid metabolic disorders and mortality in broiler breeders. 3. Given that poultry selection is a global large-scale business and chickens are a prolific species, improvement in profit can only be obtained by selecting on feed conversion and/or for higher breast meat percentage, which will intensify the broiler-breeder paradox. 4. New feeding strategies are being studied, but it is questionable if the paradox can be solved by management tools alone. Because breeding and selection are long-term processes, involving animals, farmers, consumers, industry, environment etc., a more sustainable breeding goal needs to be determined by a multidisciplinary approach and an open debate between several actors in the discussion. 5. Using dwarf broiler breeder hens could be one alternative, because dwarf hens combine relatively good reproductive fitness with ad libitum feeding. Another possibility is to accept lower broiler productivity by assigning economic values to welfare and including integrity traits in an extended breeding goal.

  9. Spin entanglement, decoherence and Bohm's EPR paradox.

    Science.gov (United States)

    Cavalcanti, E G; Drummond, P D; Bachor, H A; Reid, M D

    2009-10-12

    We obtain criteria for entanglement and the EPR paradox for spin-entangled particles and analyse the effects of decoherence caused by absorption and state purity errors. For a two qubit photonic state, entanglement can occur for all transmission efficiencies. In this case, the state preparation purity must be above a threshold value. However, Bohm's spin EPR paradox can be achieved only above a critical level of loss. We calculate a required efficiency of 58%, which appears achievable with current quantum optical technologies. For a macroscopic number of particles prepared in a correlated state, spin entanglement and the EPR paradox can be demonstrated using our criteria for efficiencies eta > 1/3 and eta > 2/3 respectively. This indicates a surprising insensitivity to loss decoherence, in a macroscopic system of ultra-cold atoms or photons.

  10. The Lindley paradox in optical interferometry

    International Nuclear Information System (INIS)

    Mauri, Camillo; Paris, Matteo G.A.

    2016-01-01

    The so-called Lindley paradox is a counterintuitive statistical effect where the Bayesian and frequentist approaches to hypothesis testing give radically different answers, depending on the choice of the prior distribution. In this paper we address the occurrence of the Lindley paradox in optical interferometry and discuss its implications for high-precision measurements. In particular, we focus on phase estimation by Mach–Zehnder interferometers and show how to mitigate the conflict between the two approaches by using suitable priors. - Highlights: • We address the occurence of Lindley paradox in interferometry and discuss its implications for high-precision measurements. • We show how to mitigate the conflict between Bayesian and frequentist approach to interferometry using suitable priors. • Our results apply to calibration of homodyne detectors for quantum tomography.

  11. Thermoeconomic diagnosis and entropy generation paradox

    DEFF Research Database (Denmark)

    Sigthorsson, Oskar; Ommen, Torben Schmidt; Elmegaard, Brian

    2017-01-01

    In the entropy generation paradox, the entropy generation number, as a function of heat exchanger effectiveness, counter-intuitively approaches zero in two limits symmetrically from a single maximum. In thermoeconomic diagnosis, namely in the characteristic curve method, the exergy destruction...... to the entropy generation paradox, as a decreased heat exchanger effectiveness (as in the case of an operation anomaly in the component) can counter-intuitively result in decreased exergy destruction rate of the component. Therefore, along with an improper selection of independent variables, the heat exchanger...... increases in case of an operation anomaly in a component. The normalised exergy destruction rate as the dependent variable therefore resolves the relation of the characteristic curve method with the entropy generation paradox....

  12. Nietzsche et les paradoxes de la force

    Directory of Open Access Journals (Sweden)

    Arnaud François

    2011-06-01

    Full Text Available According to this paper, the Nietzschean notion of force actually consists of a number of paradoxes, which I seek to formulate through the philosophical problems they pose. These paradoxes revolve around this fundamental paradox: on the one hand, force is able to rise and fall, but precisely how could such an increase and such a decrease be designed, as far as only what is given once for all can accept quantitative determinations? I come to draw two methods to answer this question (contrariety between two positive forces, reactivity of one force against the other, which suggest two ways of posing the biological and medical problems today, related to the notions of health and disease, in the scope of which Nietzsche has encountered it.

  13. Einstein-Podolsky-Rosen paradox and measurement of quantum system

    OpenAIRE

    Kladko, Konstantin

    1999-01-01

    Einstein-Podolsky-Rosen (EPR) paradox is considered in a relation to a measurement of an arbitrary quantum system . It is shown that the EPR paradox always appears in a gedanken experiment with two successively joined measuring devices.

  14. Another paradox involving the second law of thermodynamics

    International Nuclear Information System (INIS)

    Sheehan, D.P.

    1996-01-01

    Recently a paradox has been posed that appears to challenge the second law of thermodynamics in a plasma blackbody environment [D. P. Sheehan, Phys. Plasmas 2, 1893 (1995)]. In this paper another, related paradox is posed in an unmagnetized Q plasma. Laboratory experiments simulating some necessary conditions for the paradoxical system corroborate theoretical predictions and fail to resolve the paradox in favor of the second law. copyright 1996 American Institute of Physics

  15. Micro-Macro Paradoxes of Entrepreneurship

    DEFF Research Database (Denmark)

    Søgaard, Villy

    2008-01-01

    Artiklen tager afsæt i det såkaldte micro-macro paradox fra Aids-Efficiency litteraturen og argumenterer for, at en tilsvarende problemstilling bør inddrages i vurderingen af f.eks. de beskæftigelsesmæssige konsekvenser af entrepreneuriel virksomhed. Den påviser også i en gennemgang af litteratur...

  16. Art's Pedagogical Paradox

    Science.gov (United States)

    Kalin, Nadine M.

    2014-01-01

    This article contributes to conversations concerning art education futures through engaging alternative relations between art, education, and democracy that mobilize education as art projects associated with the "pedagogical turn" as sites of liminality and paradox. An analysis of the art project, Pedagogical Factory, is used to outline…

  17. An alternative resolution to the Mansuripur paradox

    Science.gov (United States)

    Redfern, Francis

    2016-04-01

    In 2013 an article published online by the journal Science declared that the paradox proposed by Masud Mansuripur was resolved. This paradox concerns a point charge-Amperian magnetic dipole system as seen in a frame of reference where they are at rest and one in which they are moving. In the latter frame an electric dipole appears on the magnetic dipole. A torque is then exerted upon the electric dipole by the point charge, a torque that is not observed in the at-rest frame. Mansuripur points out this violates the relativity principle and suggests the Lorentz force responsible for the torque be replaced by the Einstein-Laub force. The resolution of the paradox reported by Science, based on numerous papers in the physics literature, preserves the Lorentz force but depends on the concept of hidden momentum. Here I propose a different resolution based on the overlooked fact that the charge-magnetic dipole system contains linear and angular electromagnetic field momentum. The time rate of change of the field angular-momentum in the frame through which the system is moving cancels that due to the charge-electric dipole interaction. From this point of view hidden momentum is not needed in the resolution of the paradox.

  18. Consistent resolution of some relativistic quantum paradoxes

    International Nuclear Information System (INIS)

    Griffiths, Robert B.

    2002-01-01

    A relativistic version of the (consistent or decoherent) histories approach to quantum theory is developed on the basis of earlier work by Hartle, and used to discuss relativistic forms of the paradoxes of spherical wave packet collapse, Bohm's formulation of the Einstein-Podolsky-Rosen paradox, and Hardy's paradox. It is argued that wave function collapse is not needed for introducing probabilities into relativistic quantum mechanics, and in any case should never be thought of as a physical process. Alternative approaches to stochastic time dependence can be used to construct a physical picture of the measurement process that is less misleading than collapse models. In particular, one can employ a coarse-grained but fully quantum-mechanical description in which particles move along trajectories, with behavior under Lorentz transformations the same as in classical relativistic physics, and detectors are triggered by particles reaching them along such trajectories. States entangled between spacelike separate regions are also legitimate quantum descriptions, and can be consistently handled by the formalism presented here. The paradoxes in question arise because of using modes of reasoning which, while correct for classical physics, are inconsistent with the mathematical structure of quantum theory, and are resolved (or tamed) by using a proper quantum analysis. In particular, there is no need to invoke, nor any evidence for, mysterious long-range superluminal influences, and thus no incompatibility, at least from this source, between relativity theory and quantum mechanics

  19. Paradoxical psychotherapy in a case of transvestism.

    Science.gov (United States)

    Cliffe, M J

    1987-09-01

    Paradoxical psychotherapy succeeded in removing the compulsive element and reducing the guilt attached to transvestism in a male transvestite patient. Cross-dressing at home became acceptable to him and the temptation to cross-dress in public ended. Data suggested three independent motivational systems in this patient.

  20. Political Animals: The Paradox of Ecofeminist Politics.

    Science.gov (United States)

    Sandilands, Catriona

    1994-01-01

    Analyzes the paradox between the careful work of rigorous political analysis and philosophy and a desire for mystery and the experience of awe and wildness that demands putting aside careful reasoning and the sensing of nature in an altogether different way. (LZ)

  1. Calcium paradox and calcium entry blockers

    NARCIS (Netherlands)

    Ruigrok, T.J.C.; Slade, A.M.; Nayler, W.G.; Meijler, F.L.

    1984-01-01

    Reperfusion of isolated hearts with calcium-containing solution after a short period of calcium-free perfusion results in irreversible cell damage (calcium paradox). This phenomenon is characterized by an excessive influx of calcium into the cells, the rapid onset of myocardial contracture,

  2. Embracing uncertainties: The paradox of environmental education ...

    African Journals Online (AJOL)

    This paper is a pair of binoculars which I have used to scan the last two years that I have been studying environmental education, the focus being on the research I did on Theatre for Development for environmental education in formal education. The paper aims to bring into view some on the paradoxes of doing ...

  3. Zeno's paradox in quantum cellular automata

    International Nuclear Information System (INIS)

    Groessing, G.; Zeilinger, A.

    1991-01-01

    The effect of Zeno's paradox in quantum theory is demonstrated with the aid of quantum mechanical cellular automata. It is shown that the degree of non-unitarity of the cellular automaton evolution and the frequency of consecutive measurements of cellular automaton states are operationally indistinguishable. (orig.)

  4. Zeno's paradox in quantum cellular automata

    Energy Technology Data Exchange (ETDEWEB)

    Groessing, G [Atominst. der Oesterreichischen Universitaeten, Vienna (Austria); Zeilinger, A [Inst. fuer Experimentalphysik, Univ. Innsbruck (Austria)

    1991-07-01

    The effect of Zeno's paradox in quantum theory is demonstrated with the aid of quantum mechanical cellular automata. It is shown that the degree of non-unitarity of the cellular automaton evolution and the frequency of consecutive measurements of cellular automaton states are operationally indistinguishable. (orig.).

  5. A new explanation of the extinction paradox

    International Nuclear Information System (INIS)

    Berg, M.J.; Sorensen, C.M.; Chakrabarti, A.

    2011-01-01

    This work presents a new explanation for the extinction paradox and shows that the canonical explanations are incorrect. This paradox refers to the large size limit of a particle's extinction cross section. It is called a paradox because the geometrical optics approximation, which should be valid in this limit, predicts a cross section that is half of the true value. The new explanation is achieved by formulating the scattered wave in terms of an integral over the particle's surface where the seemingly unrelated Ewald-Oseen theorem appears in the formulation. By expressing the cross section in terms of this surface integral, the Ewald-Oseen theorem is analytically connected to the cross section. Several illustrations are used to reveal the significance of this connection: The paradox is seen to be a consequence of the requirement that the incident wave be canceled within the particle by secondary radiation from its own internal field. Following this, the canonical explanations are examined to reveal serious problems. In the process, the same asymptotic extinction behavior is shown to occur for small highly refractive dielectric particles, and thus is not just a large particle size or small wavelength effect as is often stated. The traditional explanations cannot account for this behavior while the new one actually predicts it. All in all, this work constitutes a fundamental reworking of 60 years of accepted understanding for the cause of the asymptotic behavior of the extinction cross section.

  6. The Einstein-Podolsky-Rosen paradox

    International Nuclear Information System (INIS)

    Roy, S.M.

    1980-01-01

    The celebrated arguments of Einstein, Podolsky and Rosen claiming that quantum mechanics cannot be a complete theory are reviewed. Recent research climaxed by Bell's theorem shows that Einstein's locality or ''no telepathy'' postulate conflicts with quantum theory. It adds a new dimension to the paradox by catapulting the problem from the domain of metaphysics into that of experimental physics. (auth.)

  7. On a paradox of probability theory

    International Nuclear Information System (INIS)

    Stuart, C.I.J.M.

    1989-01-01

    Costa de Beauregard's proposal concerning physical retrocausality has been shown to fail on two crucial points. However, it is argued that his proposal still merits serious attention. The argument arises from showing that his proposal reveals a paradox involving relations between conditional probabilities, statistical correlations and reciprocal causalities of the type exhibited by cooperative dynamics in physical systems. 4 refs. (Author)

  8. An alternative resolution to the Mansuripur paradox

    International Nuclear Information System (INIS)

    Redfern, Francis

    2016-01-01

    In 2013 an article published online by the journal Science declared that the paradox proposed by Masud Mansuripur was resolved. This paradox concerns a point charge-Amperian magnetic dipole system as seen in a frame of reference where they are at rest and one in which they are moving. In the latter frame an electric dipole appears on the magnetic dipole. A torque is then exerted upon the electric dipole by the point charge, a torque that is not observed in the at-rest frame. Mansuripur points out this violates the relativity principle and suggests the Lorentz force responsible for the torque be replaced by the Einstein–Laub force. The resolution of the paradox reported by Science, based on numerous papers in the physics literature, preserves the Lorentz force but depends on the concept of hidden momentum. Here I propose a different resolution based on the overlooked fact that the charge-magnetic dipole system contains linear and angular electromagnetic field momentum. The time rate of change of the field angular–momentum in the frame through which the system is moving cancels that due to the charge-electric dipole interaction. From this point of view hidden momentum is not needed in the resolution of the paradox. (paper)

  9. Does evaporation paradox exist in China?

    Directory of Open Access Journals (Sweden)

    Z. T. Cong

    2009-03-01

    Full Text Available One expected consequence of global warming is the increase in evaporation. However, lots of observations show that the rate of evaporation from open pans of water has been steadily decreasing all over the world in the past 50 years. The contrast between expectation and observation is called "evaporation paradox". Based on data from 317 weather stations in China from 1956 to 2005, the trends of pan evaporation and air temperature were obtained and evaporation paradox was analyzed. The conclusions include: (1 From 1956 to 2005, pan evaporation paradox existed in China as a whole while pan evaporation kept decreasing and air temperature became warmer and warmer, but it does not apply to Northeast and Southeast China; (2 From 1956 to 1985, pan evaporation paradox existed narrowly as a whole with unobvious climate warming trend, but it does not apply to Northeast China; (3 From 1986 to 2005, in the past 20 years, pan evaporation paradox did not exist for the whole period while pan evaporation kept increasing, although it existed in South China. Furthermore, the trend of other weather factors including sunshine duration, windspeed, humidity and vapor pressure deficit, and their relations with pan evaporation are discussed. As a result, it can be concluded that pan evaporation decreasing is caused by the decreasing in radiation and wind speed before 1985 and pan evaporation increasing is caused by the decreasing in vapor pressure deficit due to strong warming after 1986. With the Budyko curve, it can be concluded that the actual evaporation decreased in the former 30 years and increased in the latter 20 year for the whole China.

  10. [Healthy obesity? Why the adiposity paradox is only seemingly paradox].

    Science.gov (United States)

    Ströhle, Alexander; Worm, Nicolai

    2014-02-01

    The health consequences of being overweight have been discussed controversially. Indeed, from a metabolic point of view, overweight and obese people are quite heterogenous. The body mass index (BMI) is not suitable to predict health oriented outcomes on an individual level without taking into account further parameters such as waist circumference, blood pressure, serum glucose, serum lipids, and physical fitness. The BMI does not distinguish between metabolically healthy and metabolically unhealthy. Of upmost importance for health consequences of obesity is body fat distribution. Two types of principally different fat distribution can be identified: abdominal and gluteofemoral fat. Waist circumference and hip circumference can be utilized to distinguish between those two types. People with accumulation of body fat in the abdominal region have a markedly higher risk of developing type-2-diabetes and cardiovascular disease. Moreover, their total mortality is increased. On the other hand, waist circumference is not sufficiently capable of indicating individual risk. Instead, the amount of visceral fat is believed to be a primary risk factor because of its metabolic characteristics (i. e. increased lipolysis, diabetogenic and atherogenic adipokine profile). Recent findings point to visceral fat being more an indicator of the parallel accumulation of fat deposits in organs placed in the abdomen. The accumulation of lipids in tissues not primary intended for fat storage is called,,ectopic fat". It can be found in muscle, liver, pancreas, and kidney. The fattening of those organs is now considered to have the key role in the pathogenesis of type-2-diabetes. The pathophysiological effects of ectopic fat and the associated metabolic derangements can solve the conflicting findings concerning health consequences of BMI--at least in part. Moreover, these findings may have therapeutic consequences. The reduction of ectopic fat as well as the modification of its metabolic

  11. A paradox of cumulative culture.

    Science.gov (United States)

    Kobayashi, Yutaka; Wakano, Joe Yuichiro; Ohtsuki, Hisashi

    2015-08-21

    Culture can grow cumulatively if socially learnt behaviors are improved by individual learning before being passed on to the next generation. Previous authors showed that this kind of learning strategy is unlikely to be evolutionarily stable in the presence of a trade-off between learning and reproduction. This is because culture is a public good that is freely exploited by any member of the population in their model (cultural social dilemma). In this paper, we investigate the effect of vertical transmission (transmission from parents to offspring), which decreases the publicness of culture, on the evolution of cumulative culture in both infinite and finite population models. In the infinite population model, we confirm that culture accumulates largely as long as transmission is purely vertical. It turns out, however, that introduction of even slight oblique transmission drastically reduces the equilibrium level of culture. Even more surprisingly, if the population size is finite, culture hardly accumulates even under purely vertical transmission. This occurs because stochastic extinction due to random genetic drift prevents a learning strategy from accumulating enough culture. Overall, our theoretical results suggest that introducing vertical transmission alone does not really help solve the cultural social dilemma problem. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. A Resolution of the Paradox of Enrichment

    Science.gov (United States)

    Feng, Z. C.; Li, Y. Charles

    2015-06-01

    The paradox of enrichment was observed by Rosenzweig [1971] in a class of predator-prey models. Two of the parameters in the models are crucial for the paradox. These two parameters are the prey's carrying capacity and prey's half-saturation for predation. Intuitively, increasing the carrying capacity due to enrichment of the prey's environment should lead to a more stable predator-prey system. Analytically, it turns out that increasing the carrying capacity always leads to an unstable predator-prey system that is susceptible to extinction from environmental random perturbations. This is the so-called paradox of enrichment. Our resolution here rests upon a closer investigation on a dimensionless number H formed from the carrying capacity and the prey's half-saturation. By recasting the models into dimensionless forms, the models are in fact governed by a few dimensionless numbers including H. The effects of the two parameters: carrying capacity and half-saturation are incorporated into the number H. In fact, increasing the carrying capacity is equivalent (i.e. has the same effect on H) to decreasing the half-saturation which implies more aggressive predation. Since there is no paradox between more aggressive predation and instability of the predator-prey system, the paradox of enrichment is resolved. The so-called instability of the predator-prey system is characterized by the existence of a stable limit cycle in the phase plane, which gets closer and closer to the predator axis and prey axis. Due to random environmental perturbations, this can lead to extinction. We also further explore spatially dependent models for which the phase space is infinite-dimensional. The spatially independent limit cycle which is generated by a Hopf bifurcation from an unstable steady state, is linearly stable in the infinite-dimensional phase space. Numerical simulations indicate that the basin of attraction of the limit cycle is riddled. This shows that spatial perturbations can

  13. Solar neutrino experiments

    International Nuclear Information System (INIS)

    Hampel, W.

    1996-01-01

    The present status of experimental solar neutrino research is reviewed. Updated results from the Homestake, Kamiokande, GALLEX and SAGE detectors all show a deficit when compared to recent standard solar model calculations. Two of these detectors, GALLEX and SAGE, have recently been checked with artificial 51 Cr neutrino sources. It is shown that astrophysical scenarios to solve the solar neutrino problems are not favoured by the data. There is hope that the results of forthcoming solar neutrino experiments can provide the answers to the open questions. (author) 6 figs., 3 tabs., 36 refs

  14. Solar neutrino experiments

    Energy Technology Data Exchange (ETDEWEB)

    Hampel, W [Max-Planck-Institut fuer Kernphysik, Heidelberg (Germany)

    1996-11-01

    The present status of experimental solar neutrino research is reviewed. Updated results from the Homestake, Kamiokande, GALLEX and SAGE detectors all show a deficit when compared to recent standard solar model calculations. Two of these detectors, GALLEX and SAGE, have recently been checked with artificial {sup 51}Cr neutrino sources. It is shown that astrophysical scenarios to solve the solar neutrino problems are not favoured by the data. There is hope that the results of forthcoming solar neutrino experiments can provide the answers to the open questions. (author) 6 figs., 3 tabs., 36 refs.

  15. The house economist and the eating paradox.

    Science.gov (United States)

    Woods, Stephen C

    2002-04-01

    An important observation of the experiments of George Collier is that animals normally prefer to maintain their body weight by eating a large number of small meals each day. However, as the effort to obtain access to food increases, the animals adapt by changing to a schedule of eating a small number of large meals each day. A strong implication of this is that there is a hidden cost to eating large meals, and this is the basis of the eating paradox that states that although food is a necessary commodity, the act of ingesting it poses certain metabolic problems for animals. Experiments on cephalic insulin secretion, conditioned insulin secretion and meal feeding are discussed to make the point that the economy demonstrated by rats in Collier's paradigm is dictated in part by predictions of the eating paradox. Copyright 2002 Elsevier Science Ltd.

  16. Un théoricien paradoxal

    Directory of Open Access Journals (Sweden)

    Jacques Dubois

    2009-08-01

    Full Text Available Professeur de littérature française à Paris-VIII et psychanalyste, Pierre Bayard a publié en quinze ans une dizaine d’ouvrages critiques dans la collection « Paradoxe » des éditions de Minuit. À croire que cette collection a été créée à sa seule intention tant chacun de ses livres inverse radicalement un principe bien établi et pousse le paradoxe jusqu’à ses ultimes conséquences, voire jusqu’à l’absurde. L’exemple le plus flagrant est ce Comment parler des livres que l’on n’a pas lus ?, qui, ...

  17. Steering, Entanglement, Nonlocality, and the EPR Paradox

    Science.gov (United States)

    Wiseman, Howard; Jones, Steve; Andrew, Doherty

    2007-06-01

    The concept of steering was introduced by Schroedinger in 1935 as a generalization of the EPR paradox for arbitrary pure bipartite entangled states and arbitrary measurements by one party. Until now, it has never been rigorously defined, so it has not been known (for example) what mixed states are steerable (that is, can be used to exhibit steering). We provide an operational definition, from which we prove (by considering Werner states and Isotropic states) that steerable states are a strict subset of the entangled states, and a strict superset of the states that can exhibit Bell-nonlocality. For arbitrary bipartite Gaussian states we derive a linear matrix inequality that decides the question of steerability via Gaussian measurements, and we relate this to the original EPR paradox.

  18. A history of the Allais paradox.

    Science.gov (United States)

    Heukelom, Floris

    2015-03-01

    This article documents the history of the Allais paradox, and shows that underneath the many discussions of the various protagonists lay different, irreconcilable epistemological positions. Savage, like his mentor von Neumann and similar to economist Friedman, worked from an epistemology of generalized characterizations. Allais, on the other hand, like economists Samuelson and Baumol, started from an epistemology of exact descriptions in which every axiom was an empirical claim that could be refuted directly by observations. As a result, the two sides failed to find a common ground. Only a few decades later was the now so-called Allais paradox rediscovered as an important precursor when a new behavioural economic subdiscipline started to adopt the epistemology of exact descriptions and its accompanying falsifications of rational choice theory.

  19. Rotating model for the equivalence principle paradox

    International Nuclear Information System (INIS)

    Wilkins, D.C.

    1975-01-01

    An idealized system is described in which two inertial frames rotate relative to one another. When a (scalar) dipole is locally at rest in one frame, a paradox arises as to whether or not it will radiate. Fluxes of energy and angular momentum and the time development of the system are discussed. Resolution of the paradox involves several unusual features, including (i) radiation by an unmoving charge, an effect discussed by Chitre, Price, and Sandberg, (ii) different power seen by relatively accelerated inertial observers, and (iii) radiation reaction due to gravitational backscattering of radiation, in agreement with the work of C. and B. DeWitt. These results are obtained, for the most part, without the complications of curved space--time

  20. Problems and paradoxes of the Lifshitz theory

    International Nuclear Information System (INIS)

    Klimchitskaya, G L

    2009-01-01

    The problems and paradoxes of the Lifshitz theory in application to real dielectric and semiconductor materials are reviewed. It is shown that the inclusion of drift current of conduction electrons into the model of dielectric response results in contradictions with both thermodynamics and experimental data of different experimental groups. Physical reasons why the problems and paradoxes arise are analyzed and found to be connected with the violation of basic applicability condition of the Lifshitz theory, the thermal equilibrium. A recent alternative approach to the resolution of the problems based on the inclusion of screening effects and diffusion current is considered and demonstrated to be thermodynamically and experimentally inconsistent. It is argued that the inclusion of the diffusion current leads to an even deeper violation of thermal equilibrium. Phenomenologically, the Lifshitz theory with role of drift and diffusion currents neglected is shown to be free of problems and in agreement with both thermodynamics and all available experimental data.

  1. The Klein paradox: a new treatment

    International Nuclear Information System (INIS)

    Truebenbacher, E

    2015-01-01

    The Dirac equation requires a treatment of the step potential that differs fundamentally from the traditional treatment, because the Dirac plane waves, besides momentum and spin, are characterized by a quantum number with the physical meaning of sign of charge. Since the Hermitean operator corresponding to this quantum number does not commute with the step potential, the time displacement parameter used in the ansatz of the stationary state does not have the physical meaning of energy. Therefore there are no paradoxal values of the ‘energy’. The new solution of the Dirac equation with a step potential is obtained. This solution, again, allows for phenomena of the Klein paradox type, but in addition it contains a positron amplitude localized at the threshold point of the step potential. (paper)

  2. The eight paradoxes of nuclear information

    International Nuclear Information System (INIS)

    Timbal-Duclaux, Louis

    1977-01-01

    As it now develops, the nuclear debate is essentially characterized by its technical, mythical and polemical fields. Due to the interrelation between these three characteristics, paradox tends to multiply, either on the requesters for information side or from those who answer it. As many problems the people or organizations, such as E.D.F. for example, have to cope with as there are parties in this debate. These different paradoxes are analyzed together with some means which permits a suitable answer to be found. To conclude it is noted that if the nuclear fear is mostly imaginary passional, irrational, the problem is not to ignore these characteristics but to 'give them a statute' [fr

  3. Klein paradox in the Breit equation

    International Nuclear Information System (INIS)

    Krolikowski, W.; Turski, A.; Rzewuski, J.

    1979-01-01

    We demonstrate that in the Breit equation with a central potential V(r) having the property V(r 0 )=E there appears a Klein paradox at r=r 0 . This phenomenon, besides the previously found Klein paradox at r→infinite appearing if V(r)→infinite at r→infinite, seems to indicate that in the Breit equation valid in the single-particle theory the sea of particle-antiparticle pairs is not well separated from the considered two-body configuration. We conjecture that both phenomena should be absent from the Salpeter equation which is consistent with the hole theory. We prove this conjecture in the limit of m( 1 )→infinite and m( 2 )→infinite, where we neglect the terms approx. 1/m( 1 ) and 1/m( 2 ). (orig./WL) [de

  4. Some human performance paradoxes of nuclear operations

    International Nuclear Information System (INIS)

    Otway, H.J.; Misenta, R.

    1980-01-01

    Roughly once a year, an abnormal situation with emergency potential may suddenly break the calm monotony of nuclear-power plant operation. The operating crew, perhaps under-stimulated by monitoring largely automatic processes, may then be expected to make correct inferences and decisions about complex phenomena. However, under stress, the operators may resort to using their 'best-learned responses', inappropriate to the real situation. Recent events at Three Mile Island prompted a variety of suggestions intended to improve operator performance, eg higher qualifications, more pay, or enhanced status. The authors stress the paradoxes of nuclear operation, conclude that some 'intuitively obvious' suggestions might have the opposite effect to that intended, and explore the possibility of introducing frequent, realistic emergency drills. Even this approach raises paradoxes - perhaps the role of the operator should be eliminated, or redefined to allow less human intervention in emergencies. (author)

  5. MODELING PARADOXES IN NOVICE AND EXPERT DESIGN

    DEFF Research Database (Denmark)

    Dorst, Kees; Hansen, Claus Thorp

    2011-01-01

    In their ICED09 paper ‘Problem formulation as a discursive activity’, the authors have used an extensive educational case study to explore a framework for describing design as a discursive activity, centered around the paradoxical nature of the problem situation. The ‘working definition’ for para......In their ICED09 paper ‘Problem formulation as a discursive activity’, the authors have used an extensive educational case study to explore a framework for describing design as a discursive activity, centered around the paradoxical nature of the problem situation. The ‘working definition...... at play in a design situation, and extract themes that can lead to reformulation of the problem as well as the creation of innovative solutions. This behaviour is compared to the ways of working of novice designers (students) in the original case study....

  6. A Canadian paradox: Tommy Douglas and eugenics.

    Science.gov (United States)

    Shevell, Michael

    2012-01-01

    Tommy Douglas is an icon of Canadian 20th Century political history and is considered by many as the "Father" of Medicare, a key component of our national identity. Throughout his career, he was associated at both the provincial and federal levels with progressive causes concerning disadvantaged populations. In his sociology Master's thesis written in the early 1930's, Douglas endorsed eugenic oriented solutions such as segregation and sterilization to address what was perceived to be an endemic and biologically determined problem. At first glance, this endorsement of eugenics appears to be paradoxical, but careful analysis revealed that this paradox has multiple roots in religion, political belief, historical exposure and our own desire to view our collective history in a favourable light.

  7. A Paraconsistentist Approach to Chisholm's Paradox

    Directory of Open Access Journals (Sweden)

    Marcelo Esteban Coniglio

    2009-12-01

    Full Text Available The Logics of Deontic (InConsistency (LDI’s can be considered as the deontic counterpart of the paraconsistent logics known as Logics of Formal (InConsistency. This paper introduces and studies new LDI’s and other paraconsistent deontic logics with different properties: systems tolerant to contradictory obligations; systems in which contradictory obligations trivialize; and a bimodal paraconsistent deontic logic combining the features of previous systems. These logics are used to analyze the well-known Chisholm’s paradox, taking profit of the fact that, besides contradictory obligations do not trivialize in LDI’s, several logical dependencies of classical logic are blocked in the context of LDI’s, allowing to dissolve the paradox.

  8. Two Paradoxes in Linear Regression Analysis

    Science.gov (United States)

    FENG, Ge; PENG, Jing; TU, Dongke; ZHENG, Julia Z.; FENG, Changyong

    2016-01-01

    Summary Regression is one of the favorite tools in applied statistics. However, misuse and misinterpretation of results from regression analysis are common in biomedical research. In this paper we use statistical theory and simulation studies to clarify some paradoxes around this popular statistical method. In particular, we show that a widely used model selection procedure employed in many publications in top medical journals is wrong. Formal procedures based on solid statistical theory should be used in model selection. PMID:28638214

  9. Elevation in brain temperature during paradoxical sleep.

    Science.gov (United States)

    Kawamura, H; Sawyer, C H

    1965-11-12

    During ordinary sleep, the temperature of the rabbit brain tended to drop, but during paradoxical sleep it rose sharply 0.1 degrees to 0.4 degrees C, a greater elevation than was observed during arousal. Changes in body temperature generally did not parallel the alterations in brain temperature. Shifts of direct-current potential in the brain are basically independent of the changes in brain temperature.

  10. Steering, Entanglement, Nonlocality, and the EPR Paradox

    OpenAIRE

    Wiseman, H. M.; Jones, S. J.; Doherty, A. C.

    2006-01-01

    The concept of steering was introduced by Schrodinger in 1935 as a generalization of the EPR paradox for arbitrary pure bipartite entangled states and arbitrary measurements by one party. Until now, it has never been rigorously defined, so it has not been known (for example) what mixed states are steerable (that is, can be used to exhibit steering). We provide an operational definition, from which we prove (by considering Werner states and Isotropic states) that steerable states are a strict ...

  11. Seventy Years of the EPR Paradox

    OpenAIRE

    Kupczynski, Marian

    2007-01-01

    In spite of the fact that statistical predictions of quantum theory (QT) can only be tested if large amount of data is available a claim has been made that QT provides the most complete description of an individual physical system. Einstein's opposition to this claim and the paradox he presented in the article written together with Podolsky and Rosen in 1935 inspired generations of physicists in their quest for better understanding of QT. Seventy years after EPR article it is clear that witho...

  12. Time symmetry and the Einstein paradox

    International Nuclear Information System (INIS)

    Costa de Beauregard, O.

    1977-01-01

    The characteristic difference between the paleoquantal calculation (addition of partial probabilities) and the neoquantal one (addition of partial amplitudes) for the correlation of photon polarizations in cascade transitions is derived in terms of elementary trigonometry. This deliberate use of simple formulae aims at a transparent rendering of the change in paradigm required by the so-called EPR paradox (which is truly the 1927 Einstein paradox), namely that 1) the two photons do not possess polarizations of their own when leaving the source C, but borrow one later, when interacting with the analysers L and N; 2) the die is thus not cast at C, but later, at L and N; 3) the correlation between the measurements at L and N is tied through C, in their common past. The tight connection between this ''Einstein nonseparability'' and the nonlocality in Feynman's ''theory of positrons'' is demonstrated through an analysis of the e + e - annihilation into two photons. Thus the Einstein paradox corresponds, in the ''new wavelike probability calculus'', to the Loschmid and Zermelo sort of paradox in the old probability calculus. That is, it contrasts the intrinsic time symmetry existing at the elementary level to the factlike macroscopic time asymmetry. The discussion deliberately by-passes the hidden-variable problem, the model in this being Einstein's by-passing of the mechanical aether when proposing special relativity. It is believed today, like in 1905, the problem is tayloring the wording after the (operationally good) mathematics. Moreover, that the change in paradigm, which is needed, comes through a victory of formalism over modelism. (author)

  13. The vacuum friction paradox and related puzzles

    Science.gov (United States)

    Barnett, Stephen M.; Sonnleitner, Matthias

    2018-04-01

    The frequency of light emitted by a moving source is shifted by a factor proportional to its velocity. We find that this Doppler shift requires the existence of a paradoxical effect: that a moving atom radiating in otherwise empty space feels a net or average force acing against its direction motion and proportional in magnitude to is speed. Yet there is no preferred rest frame, either in relativity or in Newtonian mechanics, so how can there be a vacuum friction force?

  14. The Strategic Paradox of Social Networks

    Science.gov (United States)

    2011-03-18

    United States claimed to have met online.9 And in 2010, Facebook claimed over 500 million users, which would make the social networking service the...service culture, or occupational specialty. One drawback with social networks concerns the protection of individual privacy. Facebook , for...St ra te gy R es ea rc h Pr oj ec t THE STRATEGIC PARADOX OF SOCIAL NETWORKS BY COLONEL ROBERT COTE United States Marine Corps

  15. Laying the ghost of twin paradox

    Directory of Open Access Journals (Sweden)

    Popović Marko

    2009-01-01

    Full Text Available Someone's true age is not written in his ID, but in his biomarkers. Aging process is not caused by time passing, but by thermodynamically laws. Entropy, extent of metabolic reaction, and temperature are Lorentz invariant, so these facts make twin paradox impossible because there is no way for one twin to age slower than the other even if the time in his frame is dilated. Entropy is the function of state, not time. So as much as standard thermodynamics concerns, the path between two points in space is equivalent to the path between two states. Whether the point B is reached by moving faster using the longer way (with time dilatation, or slower by using shortcut (without time dilatation, the state of the system after completing the road should be the same. This is supported by the fact that when two twins reach the same space-time point (point B in which the state parameters are the same. If we use entropy as an age parameter, then both twins have the same entropy value and are exactly the same biological age. Therefore, the twin paradox is a logical mistake based on wrong first premise. Bergson symmetry is not necessary any more to explain the impossibility of twin paradox.

  16. Scientific progress despite irreproducibility: A seeming paradox.

    Science.gov (United States)

    Shiffrin, Richard M; Börner, Katy; Stigler, Stephen M

    2018-03-13

    It appears paradoxical that science is producing outstanding new results and theories at a rapid rate at the same time that researchers are identifying serious problems in the practice of science that cause many reports to be irreproducible and invalid. Certainly, the practice of science needs to be improved, and scientists are now pursuing this goal. However, in this perspective, we argue that this seeming paradox is not new, has always been part of the way science works, and likely will remain so. We first introduce the paradox. We then review a wide range of challenges that appear to make scientific success difficult. Next, we describe the factors that make science work-in the past, present, and presumably also in the future. We then suggest that remedies for the present practice of science need to be applied selectively so as not to slow progress and illustrate with a few examples. We conclude with arguments that communication of science needs to emphasize not just problems but the enormous successes and benefits that science has brought and is now bringing to all elements of modern society.

  17. Disability reconsidered: the paradox of physical therapy.

    Science.gov (United States)

    Roush, Susan E; Sharby, Nancy

    2011-12-01

    The purposes of this perspective article are: (1) to explore models of disability from the perspective of the academic discipline of disability studies (DS), (2) to consider the paradox of improving functional capacities while valuing disability as diversity, (3) to identify how physical therapy's use of the International Classification of Functioning, Disability and Health (ICF) disablement model intersects with various disability models, and (4) to apply this broader understanding of disability to physical therapist practice, education, and research. The DS literature has been critical of rehabilitation professionals, particularly targeting the medical model of disability. In contrast, advocates for a social model of disability recognize disability as diversity. It is paradoxical for physical therapy to simultaneously work to ameliorate disability while celebrating it as diversity. The ICF biopsychosocial disablement model offers a mechanism to practice within this paradox and suggests that it is no longer sufficient to conceptualize disability as a purely individual matter that requires attention in isolation from the impact of the larger society.

  18. Identifying Quantum Structures in the Ellsberg Paradox

    Science.gov (United States)

    Aerts, Diederik; Sozzo, Sandro; Tapia, Jocelyn

    2014-10-01

    Empirical evidence has confirmed that quantum effects occur frequently also outside the microscopic domain, while quantum structures satisfactorily model various situations in several areas of science, including biological, cognitive and social processes. In this paper, we elaborate a quantum mechanical model which faithfully describes the Ellsberg paradox in economics, showing that the mathematical formalism of quantum mechanics is capable to represent the ambiguity present in this kind of situations, because of the presence of contextuality. Then, we analyze the data collected in a concrete experiment we performed on the Ellsberg paradox and work out a complete representation of them in complex Hilbert space. We prove that the presence of quantum structure is genuine, that is, interference and superposition in a complex Hilbert space are really necessary to describe the conceptual situation presented by Ellsberg. Moreover, our approach sheds light on `ambiguity laden' decision processes in economics and decision theory, and allows to deal with different Ellsberg-type generalizations, e.g., the Machina paradox.

  19. Obesity and poverty paradox in developed countries.

    Science.gov (United States)

    Żukiewicz-Sobczak, Wioletta; Wróblewska, Paula; Zwoliński, Jacek; Chmielewska-Badora, Jolanta; Adamczuk, Piotr; Krasowska, Ewelina; Zagórski, Jerzy; Oniszczuk, Anna; Piątek, Jacek; Silny, Wojciech

    2014-01-01

    Obesity is a civilization disease and the proportion of people suffering from it continues to grow, especially in the developed countries. Number of obese people in Europe has increased threefold over the last 20 years. The paradox of obesity and poverty relationship is observed especially in the developed and developing countries. In developing countries, along with economic development and income growth, the number of people with overweight and obesity is increasing. This paradox has a relationship with both the easy availability and low cost of highly processed foods containing 'empty calories' and no nutritional value. To date, this paradox has been described in the United States and the United Kingdom, although many European countries are also experiencing high percentages of obese people. Among the reasons for the growing obesity in the population of poor people are: higher unemployment, lower education level, and irregular meals. Another cause of obesity is low physical activity, which among the poor is associated with a lack of money for sports equipment. Due to the large rate of deaths caused by diseases directly linked to obesity, the governments of many countries implement prevention programmes of overweight and obesity. These programmes are based primarily on educating the public about a healthy lifestyle based on healthy eating, daily physical activity and avoiding alcohol and cigarettes.

  20. Obesity and poverty paradox in developed countries

    Directory of Open Access Journals (Sweden)

    Wioletta Żukiewicz-Sobczak

    2014-09-01

    Full Text Available Obesity is a civilization disease and the proportion of people suffering from it continues to grow, especially in the developed countries. Number of obese people in Europe has increased threefold over the last 20 years. The paradox of obesity and poverty relationship is observed especially in the developed and developing countries. In developing countries, along with economic development and income growth, the number of people with overweight and obesity is increasing. This paradox has a relationship with both the easy availability and low cost of highly processed foods containing ‘empty calories’ and no nutritional value. To date, this paradox has been described in the United States and the United Kingdom, although many European countries are also experiencing high percentages of obese people. Among the reasons for the growing obesity in the population of poor people are: higher unemployment, lower education level, and irregular meals. Another cause of obesity is low physical activity, which among the poor is associated with a lack of money for sports equipment. Due to the large rate of deaths caused by diseases directly linked to obesity, the governments of many countries implement prevention programmes of overweight and obesity. These programmes are based primarily on educating the public about a healthy lifestyle based on healthy eating, daily physical activity and avoiding alcohol and cigarettes.

  1. Fermi's paradox: The last challenge for copernicanism?

    Directory of Open Access Journals (Sweden)

    Ćirković M.M.

    2009-01-01

    Full Text Available We review Fermi's paradox (or the 'Great Silence' problem, not only arguably the oldest and crucial problem for the Search for ExtraTerrestrial Intelligence (SETI, but also a conundrum of profound scientific, philosophical and cultural importance. By a simple analysis of observation selection effects, the correct resolution of Fermi's paradox is certain to tell us something about the future of humanity. Already more than three quarters of century old puzzle and a quarter of century since the last major review paper in the field by G. David Brin has generated many ingenious discussions and hypotheses. We analyze the often tacit methodological assumptions built in various answers to this puzzle and attempt a new classification of the numerous solutions proposed in an already huge literature on the subject. Finally, we consider the ramifications of various classes of hypotheses for the practical SETI projects. Somewhat paradoxically, it seems that the class of (neocatastrophic hypotheses gives, on the balance, the strongest justification to optimism regarding our current and near-future SETI efforts.

  2. Solar Neutrinos

    Directory of Open Access Journals (Sweden)

    V. Antonelli

    2013-01-01

    relevant indications on the fundamental interactions among particles. After reviewing the striking results of the last two decades, which were determinant to solve the long standing solar neutrino puzzle and refine the Standard Solar Model, we focus our attention on the more recent results in this field and on the experiments presently running or planned for the near future. The main focus at the moment is to improve the knowledge of the mass and mixing pattern and especially to study in detail the lowest energy part of the spectrum, which represents most of the solar neutrino spectrum but is still a partially unexplored realm. We discuss this research project and the way in which present and future experiments could contribute to make the theoretical framework more complete and stable, understanding the origin of some “anomalies” that seem to emerge from the data and contributing to answer some present questions, like the exact mechanism of the vacuum to matter transition and the solution of the so-called solar metallicity problem.

  3. Problem Solving and Learning

    Science.gov (United States)

    Singh, Chandralekha

    2009-07-01

    One finding of cognitive research is that people do not automatically acquire usable knowledge by spending lots of time on task. Because students' knowledge hierarchy is more fragmented, "knowledge chunks" are smaller than those of experts. The limited capacity of short term memory makes the cognitive load high during problem solving tasks, leaving few cognitive resources available for meta-cognition. The abstract nature of the laws of physics and the chain of reasoning required to draw meaningful inferences makes these issues critical. In order to help students, it is crucial to consider the difficulty of a problem from the perspective of students. We are developing and evaluating interactive problem-solving tutorials to help students in the introductory physics courses learn effective problem-solving strategies while solidifying physics concepts. The self-paced tutorials can provide guidance and support for a variety of problem solving techniques, and opportunity for knowledge and skill acquisition.

  4. Teaching Creative Problem Solving.

    Science.gov (United States)

    Christensen, Kip W.; Martin, Loren

    1992-01-01

    Interpersonal and cognitive skills, adaptability, and critical thinking can be developed through problem solving and cooperative learning in technology education. These skills have been identified as significant needs of the workplace as well as for functioning in society. (SK)

  5. Gibbs paradox of entropy of mixing experimental facts. Its rejection, and the theoretical consequences

    International Nuclear Information System (INIS)

    Lin, Shu-Kun

    1996-01-01

    Gibbs paradox statement of entropy of mixing has been regarded as the theoretical foundation of statistical mechanics, quantum theory and biophysics. However, all the relevant chemical experimental observations and logical analyses indicate that the Gibbs paradox statement is false. I prove that this statement is wrong: Gibbs paradox statement implies that entropy decreases with the increase in symmetry (as represented by a symmetry number σ; see any statistical mechanics textbook). From group theory any system has at least a symmetry number σ=1 which is the identity operation for a strictly asymmetric system. It follows that the entropy of a system is equal to, or less than, zero. However, from either von Neumann-Shannon entropy formula (S(w) =-Σ ω in p 1 ) or the Boltzmann entropy formula (S = in w) and the original definition, entropy is non-negative. Therefore, this statement is false. It should not be a surprise that for the first time, many outstanding problems such as the validity of Pauling's resonance theory, the explanation of second order phase transition phenomena, the biophysical problem of protein folding and the related hydrophobic effect, etc., can be solved. Empirical principles such as Pauli principle (and Hund's rule) and HSAB principle, etc., can also be given a theoretical explanation

  6. Paradoxical response to dexamethasone and spontaneous hypocortisolism in Cushing's disease

    Science.gov (United States)

    Lila, Anurag R; Sarathi, Vijaya; Bandgar, Tushar R; Shah, Nalini S

    2013-01-01

    Paradoxical response to dexamethasone and spontaneous development of hypocortisolism are rare features of Cushing's disease. We report a 13-year-old boy with Cushing's disease owing to a pituitary macroadenoma. On initial evaluation, he had partial suppression of serum cortisol by dexamethasone. He developed transient hypocortisolism after first adenomectomy, but the disease recurred after 1 year. Repeat evaluation showed recurrent hypercortisolism and paradoxical response to dexamethasone. He underwent second surgery and, postoperatively, hypercostisolism persisted even after 2 years of surgery. Repeat evaluations after 8 years of second surgery revealed persistent hypocortisolism despite residual tumour of same size and similar plasma adrenocorticotropic hormone (ACTH) levels. We have also shown that the paradoxical increase in serum cortisol was preceded by a paradoxical increase in ACTH. The paradoxical response persisted despite hypocortisolism. This patient with Cushing's disease had two very rare features: paradoxical response to dexamethasone and spontaneous development of hypocortisolism. PMID:23365169

  7. The Oxygen Paradox, the French Paradox, and age-related diseases.

    Science.gov (United States)

    Davies, Joanna M S; Cillard, Josiane; Friguet, Bertrand; Cadenas, Enrique; Cadet, Jean; Cayce, Rachael; Fishmann, Andrew; Liao, David; Bulteau, Anne-Laure; Derbré, Frédéric; Rébillard, Amélie; Burstein, Steven; Hirsch, Etienne; Kloner, Robert A; Jakowec, Michael; Petzinger, Giselle; Sauce, Delphine; Sennlaub, Florian; Limon, Isabelle; Ursini, Fulvio; Maiorino, Matilde; Economides, Christina; Pike, Christian J; Cohen, Pinchas; Salvayre, Anne Negre; Halliday, Matthew R; Lundquist, Adam J; Jakowec, Nicolaus A; Mechta-Grigoriou, Fatima; Mericskay, Mathias; Mariani, Jean; Li, Zhenlin; Huang, David; Grant, Ellsworth; Forman, Henry J; Finch, Caleb E; Sun, Patrick Y; Pomatto, Laura C D; Agbulut, Onnik; Warburton, David; Neri, Christian; Rouis, Mustapha; Cillard, Pierre; Capeau, Jacqueline; Rosenbaum, Jean; Davies, Kelvin J A

    2017-12-01

    A paradox is a seemingly absurd or impossible concept, proposition, or theory that is often difficult to understand or explain, sometimes apparently self-contradictory, and yet ultimately correct or true. How is it possible, for example, that oxygen "a toxic environmental poison" could be also indispensable for life (Beckman and Ames Physiol Rev 78(2):547-81, 1998; Stadtman and Berlett Chem Res Toxicol 10(5):485-94, 1997)?: the so-called Oxygen Paradox (Davies and Ursini 1995; Davies Biochem Soc Symp 61:1-31, 1995). How can French people apparently disregard the rule that high dietary intakes of cholesterol and saturated fats (e.g., cheese and paté) will result in an early death from cardiovascular diseases (Renaud and de Lorgeril Lancet 339(8808):1523-6, 1992; Catalgol et al. Front Pharmacol 3:141, 2012; Eisenberg et al. Nat Med 22(12):1428-1438, 2016)?: the so-called, French Paradox. Doubtless, the truth is not a duality and epistemological bias probably generates apparently self-contradictory conclusions. Perhaps nowhere in biology are there so many apparently contradictory views, and even experimental results, affecting human physiology and pathology as in the fields of free radicals and oxidative stress, antioxidants, foods and drinks, and dietary recommendations; this is particularly true when issues such as disease-susceptibility or avoidance, "healthspan," "lifespan," and ageing are involved. Consider, for example, the apparently paradoxical observation that treatment with low doses of a substance that is toxic at high concentrations may actually induce transient adaptations that protect against a subsequent exposure to the same (or similar) toxin. This particular paradox is now mechanistically explained as "Adaptive Homeostasis" (Davies Mol Asp Med 49:1-7, 2016; Pomatto et al. 2017a; Lomeli et al. Clin Sci (Lond) 131(21):2573-2599, 2017; Pomatto and Davies 2017); the non-damaging process by which an apparent toxicant can activate biological signal

  8. Exploring the isopycnal mixing and helium-heat paradoxes in a suite of Earth system models

    Science.gov (United States)

    Gnanadesikan, A.; Pradal, M.-A.; Abernathey, R.

    2015-07-01

    This paper uses a suite of Earth system models which simulate the distribution of He isotopes and radiocarbon to examine two paradoxes in Earth science, each of which results from an inconsistency between theoretically motivated global energy balances and direct observations. The helium-heat paradox refers to the fact that helium emissions to the deep ocean are far lower than would be expected given the rate of geothermal heating, since both are thought to be the result of radioactive decay in Earth's interior. The isopycnal mixing paradox comes from the fact that many theoretical parameterizations of the isopycnal mixing coefficient ARedi that link it to baroclinic instability project it to be small (of order a few hundred m2 s-1) in the ocean interior away from boundary currents. However, direct observations using tracers and floats (largely in the upper ocean) suggest that values of this coefficient are an order of magnitude higher. Helium isotopes equilibrate rapidly with the atmosphere and thus exhibit large gradients along isopycnals while radiocarbon equilibrates slowly and thus exhibits smaller gradients along isopycnals. Thus it might be thought that resolving the isopycnal mixing paradox in favor of the higher observational estimates of ARedi might also solve the helium paradox, by increasing the transport of mantle helium to the surface more than it would radiocarbon. In this paper we show that this is not the case. In a suite of models with different spatially constant and spatially varying values of ARedi the distribution of radiocarbon and helium isotopes is sensitive to the value of ARedi. However, away from strong helium sources in the southeastern Pacific, the relationship between the two is not sensitive, indicating that large-scale advection is the limiting process for removing helium and radiocarbon from the deep ocean. The helium isotopes, in turn, suggest a higher value of ARedi below the thermocline than is seen in theoretical

  9. Temperature relaxation and the Kapitza boundary resistance paradox

    OpenAIRE

    Brink, Alec Maassen van den; Dekker, H.

    1994-01-01

    The calculation of the Kapitza boundary resistance between dissimilar harmonic solids has since long (Little [Can. J. Phys. 37, 334 (1959)]) suffered from a paradox: this resistance erroneously tends to a finite value in the limit of identical solids. We resolve this paradox by calculating temperature differences in the final heat-transporting state, rather than with respect to the initial state of local equilibrium. For a one-dimensional model we thus derive an exact, paradox-free formula fo...

  10. On Hardy's paradox, weak measurements, and multitasking diagrams

    International Nuclear Information System (INIS)

    Meglicki, Zdzislaw

    2011-01-01

    We discuss Hardy's paradox and weak measurements by using multitasking diagrams, which are introduced to illustrate the progress of quantum probabilities through the double interferometer system. We explain how Hardy's paradox is avoided and elaborate on the outcome of weak measurements in this context. -- Highlights: → Hardy's paradox explained and eliminated. → Weak measurements: what is really measured? → Multitasking diagrams: introduced and used to discuss quantum mechanical processes.

  11. A Dichotomic Analysis of the Surprise Examination Paradox

    OpenAIRE

    Franceschi, Paul

    2002-01-01

    This paper presents a dichotomic analysis of the surprise examination paradox. In section 1, I analyse the surprise notion in detail. I introduce then in section 2, the distinction between a monist and dichotomic analysis of the paradox. I also present there a dichotomy leading to distinguish two basically and structurally different versions of the paradox, respectively based on a conjoint and a disjoint definition of the surprise. In section 3, I describe the solution to SEP corresponding to...

  12. The Surprise Examination Paradox and the Second Incompleteness Theorem

    OpenAIRE

    Kritchman, Shira; Raz, Ran

    2010-01-01

    We give a new proof for Godel's second incompleteness theorem, based on Kolmogorov complexity, Chaitin's incompleteness theorem, and an argument that resembles the surprise examination paradox. We then go the other way around and suggest that the second incompleteness theorem gives a possible resolution of the surprise examination paradox. Roughly speaking, we argue that the flaw in the derivation of the paradox is that it contains a hidden assumption that one can prove the consistency of the...

  13. CW- and pulsed-EPR of carbonaceous matter in primitive meteorites: solving a lineshape paradox.

    Science.gov (United States)

    Delpoux, Olivier; Gourier, Didier; Binet, Laurent; Vezin, Hervé; Derenne, Sylvie; Robert, François

    2008-05-01

    Insoluble organic matter (IOM) of Orgueil and Tagish Lake meteorites are studied by CW-EPR and pulsed-EPR spectroscopies. The EPR line is due to polycyclic paramagnetic moieties concentrated in defect-rich regions of the IOM, with concentrations of the order of 4x10(19) spin/g. CW-EPR reveals two types of paramagnetic defects: centres with S=1/2, and centres with S=0 ground state and thermally accessible triple state S=1. In spite of the Lorentzian shape of the EPR and its narrowing upon increasing the spin concentration, the EPR line is not in the exchange narrowing regime as previously deduced from multi-frequency CW-EPR [L. Binet, D. Gourier, Appl. Magn. Reson. 30 (2006) 207-231]. It is inhomogeneously broadened as demonstrated by the presence of nuclear modulations in the spin-echo decay. The line narrowing, similar to an exchange narrowing effect, is the result of an increasing contribution of the narrow line of the triplet state centres in addition to the broader line of doublet states. Hyperfine sublevel correlation spectroscopy (HYSCORE) of hydrogen and (13)C nuclei indicates that IOM* centres are small polycyclic moieties that are moderately branched with aliphatic chains, as shown by the presence of aromatic hydrogen atoms. On the contrary the lack of such aromatic hydrogen in triplet states suggests that these radicals are most probably highly branched. Paramagnetic centres are considerably enriched in deuterium, with D/H approximately 1.5+/-0.5x10(-2) of the order of values existing in interstellar medium.

  14. CW- and pulsed-EPR of carbonaceous matter in primitive meteorites: Solving a lineshape paradox

    Science.gov (United States)

    Delpoux, Olivier; Gourier, Didier; Binet, Laurent; Vezin, Hervé; Derenne, Sylvie; Robert, François

    2008-05-01

    Insoluble organic matter (IOM) of Orgueil and Tagish Lake meteorites are studied by CW-EPR and pulsed-EPR spectroscopies. The EPR line is due to polycyclic paramagnetic moieties concentrated in defect-rich regions of the IOM, with concentrations of the order of 4 × 10 19 spin/g. CW-EPR reveals two types of paramagnetic defects: centres with S = 1/2, and centres with S = 0 ground state and thermally accessible triple state S = 1. In spite of the Lorentzian shape of the EPR and its narrowing upon increasing the spin concentration, the EPR line is not in the exchange narrowing regime as previously deduced from multi-frequency CW-EPR [L. Binet, D. Gourier, Appl. Magn. Reson. 30 (2006) 207-231]. It is inhomogeneously broadened as demonstrated by the presence of nuclear modulations in the spin-echo decay. The line narrowing, similar to an exchange narrowing effect, is the result of an increasing contribution of the narrow line of the triplet state centres in addition to the broader line of doublet states. Hyperfine sublevel correlation spectroscopy (HYSCORE) of hydrogen and 13C nuclei indicates that IOM rad centres are small polycyclic moieties that are moderately branched with aliphatic chains, as shown by the presence of aromatic hydrogen atoms. On the contrary the lack of such aromatic hydrogen in triplet states suggests that these radicals are most probably highly branched. Paramagnetic centres are considerably enriched in deuterium, with D/H ≈ 1.5 ± 0.5 × 10 -2 of the order of values existing in interstellar medium.

  15. Workers Can't Find Jobs, Jobs Can't Find Workers: Solving the Talent Paradox

    Science.gov (United States)

    Rao, Harika

    2015-01-01

    The purpose of the research was to understand the latest job skill requirements for undergraduates from the real world as perceived by the students themselves and their career counselors at a university in South Florida. The study intended to provide relevant inputs to enhance the marketability of the undergraduate students by seamless…

  16. Can hydrodynamic contact line paradox be solved by evaporation-condensation?

    Science.gov (United States)

    Janeček, V; Doumenc, F; Guerrier, B; Nikolayev, V S

    2015-12-15

    We investigate a possibility to regularize the hydrodynamic contact line singularity in the configuration of partial wetting (liquid wedge on a solid substrate) via evaporation-condensation, when an inert gas is present in the atmosphere above the liquid. The no-slip condition is imposed at the solid-liquid interface and the system is assumed to be isothermal. The mass exchange dynamics is controlled by vapor diffusion in the inert gas and interfacial kinetic resistance. The coupling between the liquid meniscus curvature and mass exchange is provided by the Kelvin effect. The atmosphere is saturated and the substrate moves at a steady velocity with respect to the liquid wedge. A multi-scale analysis is performed. The liquid dynamics description in the phase-change-controlled microregion and visco-capillary intermediate region is based on the lubrication equations. The vapor diffusion is considered in the gas phase. It is shown that from the mathematical point of view, the phase exchange relieves the contact line singularity. The liquid mass is conserved: evaporation existing on a part of the meniscus and condensation occurring over another part compensate exactly each other. However, numerical estimations carried out for three common fluids (ethanol, water and glycerol) at the ambient conditions show that the characteristic length scales are tiny. Copyright © 2015 Elsevier Inc. All rights reserved.

  17. Extended dust in dwarf galaxies - solving an energy-budget paradox?

    Science.gov (United States)

    Keel, William C.; Holwerda, Benne; Lintott, Chris; Schawinski, Kevin

    2012-02-01

    The role of dust in shaping the emerging spectral energy distributions of galaxies remains poorly understood; recent Herschel results suggest large amounts of cold dust coupled with only modest optical extinction for much of the galaxy population. Previous work has used the discovery of a silhouetted-galaxy pair of a backlit dwarf galaxy with dust features extending beyond the de Vaucouleurs radius to investigate this question. We propose to examine a larger set of galaxies of this type drawn from the Galaxy Zoo catalog of silhouetted-galaxy pairs, to see whether a significant fraction of dwarfs have such extensive dust distributions. The catalog contains ~ 150 candidate backlit dwarfs; if such dust distributions are common enough to account for the Herschel results, we would see many additional cases of silhouetted dust beyond their stellar disks.

  18. Using process-oriented interfaces for solving the automation paradox in highly automated navy vessels

    NARCIS (Netherlands)

    Diggelen, J. van; Post, W.; Rakhorst, M.; Plasmeijer, R.; Staal, W. van

    2014-01-01

    This paper describes a coherent engineering method for developing high level human machine interaction within a highly automated environment consisting of sensors, actuators, automatic situation assessors and planning devices. Our approach combines ideas from cognitive work analysis, cognitive

  19. Can living labs solve the knowledge paradox? A case study of the Netherlands

    NARCIS (Netherlands)

    Van Geenhuizen, M.S.

    2011-01-01

    The Netherlands is facing a situation in which much knowledge is created at universities but small amounts are brought to market. Various indicators point to missing links in knowledge valorization in this country. To arrive at a better understanding of knowledge valorization the paper presents an

  20. Paradox in a non-linear capacitated transportation problem

    Directory of Open Access Journals (Sweden)

    Dahiya Kalpana

    2006-01-01

    Full Text Available This paper discusses a paradox in fixed charge capacitated transportation problem where the objective function is the sum of two linear fractional functions consisting of variables costs and fixed charges respectively. A paradox arises when the transportation problem admits of an objective function value which is lower than the optimal objective function value, by transporting larger quantities of goods over the same route. A sufficient condition for the existence of a paradox is established. Paradoxical range of flow is obtained for any given flow in which the corresponding objective function value is less than the optimum value of the given transportation problem. Numerical illustration is included in support of theory.

  1. Distributed Problem-Solving

    DEFF Research Database (Denmark)

    Chemi, Tatiana

    2016-01-01

    This chapter aims to deconstruct some persistent myths about creativity: the myth of individualism and of the genius. By looking at literature that approaches creativity as a participatory and distributed phenomenon and by bringing empirical evidence from artists’ studios, the author presents a p......, what can educators at higher education learn from the ways creative groups solve problems? How can artists contribute to inspiring higher education?......This chapter aims to deconstruct some persistent myths about creativity: the myth of individualism and of the genius. By looking at literature that approaches creativity as a participatory and distributed phenomenon and by bringing empirical evidence from artists’ studios, the author presents...... a perspective that is relevant to higher education. The focus here is on how artists solve problems in distributed paths, and on the elements of creative collaboration. Creative problem-solving will be looked at as an ongoing dialogue that artists engage with themselves, with others, with recipients...

  2. Paradox Lost? No, Paradox Found! Reply to Tomasello and Akhtar (2003).

    Science.gov (United States)

    Naigles, Letitia R.

    2003-01-01

    Asserts that the posited paradox between infancy and toddlerhood language was not eliminated by Tomasello and Akhtar's appeal to infants' robust statistical learning abilities. Maintains that scrutiny of their studies supports the resolution that abstracting linguistic form is easy for infants and that toddlers find it difficult to integrate…

  3. Seventy Years of the EPR Paradox

    Science.gov (United States)

    Kupczynski, Marian

    2006-11-01

    In spite of the fact that statistical predictions of quantum theory (QT) can only be tested if large amount of data is available a claim has been made that QT provides the most complete description of an individual physical system. Einstein's opposition to this claim and the paradox he presented in the article written together with Podolsky and Rosen in 1935 inspired generations of physicists in their quest for better understanding of QT. Seventy years after EPR article it is clear that without deep understanding of the character and limitations of QT one may not hope to find a meaningful unified theory of all physical interactions, manipulate qubits or construct a quantum computer.. In this paper we present shortly the EPR paper, the discussion, which followed it and Bell inequalities (BI). To avoid various paradoxes we advocate purely statistical contextual interpretation (PSC) of QT. According to PSC a state vector is not an attribute of a single electron, photon, trapped ion or quantum dot. A value of an observable assigned to a physical system has only a meaning in a context of a particular physical experiment PSC does not provide any mental space-time picture of sub phenomena. The EPR paradox is avoided because the reduction of the state vector in the measurement process is a passage from a description of the whole ensemble of the experimental results to a particular sub-ensemble of these results. We show that the violation of BI is neither a proof of the completeness of QT nor of its non-locality. Therefore we rephrase the EPR question and ask whether QT is "predictably "complete or in other words does it provide the complete description of experimental data. To test the "predictable completeness" it is not necessary to perform additional experiments it is sufficient to analyze more in detail the existing experimental data by using various non-parametric purity tests and other specific statistical tools invented to study the fine structure the time-series.

  4. Vitamin paradox in obesity: Deficiency or excess?

    Science.gov (United States)

    Zhou, Shi-Sheng; Li, Da; Chen, Na-Na; Zhou, Yiming

    2015-08-25

    Since synthetic vitamins were used to fortify food and as supplements in the late 1930s, vitamin intake has significantly increased. This has been accompanied by an increased prevalence of obesity, a condition associated with diabetes, hypertension, cardiovascular disease, asthma and cancer. Paradoxically, obesity is often associated with low levels of fasting serum vitamins, such as folate and vitamin D. Recent studies on folic acid fortification have revealed another paradoxical phenomenon: obesity exhibits low fasting serum but high erythrocyte folate concentrations, with high levels of serum folate oxidation products. High erythrocyte folate status is known to reflect long-term excess folic acid intake, while increased folate oxidation products suggest an increased folate degradation because obesity shows an increased activity of cytochrome P450 2E1, a monooxygenase enzyme that can use folic acid as a substrate. There is also evidence that obesity increases niacin degradation, manifested by increased activity/expression of niacin-degrading enzymes and high levels of niacin metabolites. Moreover, obesity most commonly occurs in those with a low excretory reserve capacity (e.g., due to low birth weight/preterm birth) and/or a low sweat gland activity (black race and physical inactivity). These lines of evidence raise the possibility that low fasting serum vitamin status in obesity may be a compensatory response to chronic excess vitamin intake, rather than vitamin deficiency, and that obesity could be one of the manifestations of chronic vitamin poisoning. In this article, we discuss vitamin paradox in obesity from the perspective of vitamin homeostasis.

  5. The paradox of strategic environmental assessment

    Energy Technology Data Exchange (ETDEWEB)

    Bidstrup, Morten, E-mail: bidstrup@plan.aau.dk; Hansen, Anne Merrild, E-mail: merrild@plan.aau.dk

    2014-07-01

    Strategic Environmental Assessment (SEA) is a tool that can facilitate sustainable development and improve decision-making by introducing environmental concern early in planning processes. However, various international studies conclude that current planning practice is not taking full advantage of the tool, and we therefore define the paradox of SEA as the methodological ambiguity of non-strategic SEA. This article explores causality through at three-step case study on aggregates extraction planning in Denmark, which consists of a document analysis; a questionnaire survey and follow-up communication with key planners. Though the environmental reports on one hand largely lack strategic considerations, practitioners express an inherent will for strategy and reveal that their SEAs in fact have been an integrated part of the planning process. Institutional context is found to be the most significant barrier for a strategy and this suggests that non-strategic planning setups can prove more important than non-strategic planning in SEA practice. Planners may try to execute strategy within the confinements of SEA-restricted planning contexts; however, such efforts can be overlooked if evaluated by a narrow criterion for strategy formation. Consequently, the paradox may also spark from challenged documentation. These findings contribute to the common understanding of SEA quality; however, further research is needed on how to communicate and influence the strategic options which arguably remain inside non-strategic planning realities. - Highlights: • International studies conclude that SEAs are not strategic. = The paradox of SEA. • Even on the highest managerial level, some contexts do not leave room for strategy. • Non-strategic SEA can derive from challenged documentation. • Descriptive and emergent strategy formation can, in practice, be deemed non-strategic.

  6. The paradox of strategic environmental assessment

    International Nuclear Information System (INIS)

    Bidstrup, Morten; Hansen, Anne Merrild

    2014-01-01

    Strategic Environmental Assessment (SEA) is a tool that can facilitate sustainable development and improve decision-making by introducing environmental concern early in planning processes. However, various international studies conclude that current planning practice is not taking full advantage of the tool, and we therefore define the paradox of SEA as the methodological ambiguity of non-strategic SEA. This article explores causality through at three-step case study on aggregates extraction planning in Denmark, which consists of a document analysis; a questionnaire survey and follow-up communication with key planners. Though the environmental reports on one hand largely lack strategic considerations, practitioners express an inherent will for strategy and reveal that their SEAs in fact have been an integrated part of the planning process. Institutional context is found to be the most significant barrier for a strategy and this suggests that non-strategic planning setups can prove more important than non-strategic planning in SEA practice. Planners may try to execute strategy within the confinements of SEA-restricted planning contexts; however, such efforts can be overlooked if evaluated by a narrow criterion for strategy formation. Consequently, the paradox may also spark from challenged documentation. These findings contribute to the common understanding of SEA quality; however, further research is needed on how to communicate and influence the strategic options which arguably remain inside non-strategic planning realities. - Highlights: • International studies conclude that SEAs are not strategic. = The paradox of SEA. • Even on the highest managerial level, some contexts do not leave room for strategy. • Non-strategic SEA can derive from challenged documentation. • Descriptive and emergent strategy formation can, in practice, be deemed non-strategic

  7. Connectable solar air collectors

    Energy Technology Data Exchange (ETDEWEB)

    Oestergaard Jensen, S.; Bosanac, M.

    2002-02-01

    The project has proved that it is possible to manufacture solar air collector panels, which in an easy way can be connected into large collector arrays with integrated ducting without loss of efficiency. The developed connectable solar air collectors are based on the use of matrix absorbers in the form of perforated metal sheets. Three interconnected solar air collectors of the above type - each with an transparent area of approx. 3 m{sup 2} - was tested and compared with parallel tests on two single solar air collectors also with a transparent area of approx. 3 m{sup 2} One of the single solar air collectors has an identical absorber as the connectable solar air collectors while the absorber of the other single solar air collector was a fibre cloth. The efficiency of the three solar air collectors proved to be almost identical in the investigated range of mass flow rates and temperature differences. The solar air collectors further proved to be very efficient - as efficient as the second most efficient solar air collectors tested in the IEA task 19 project Solar Air Systems. Some problems remain although to be solved: the pressure drop across especially the connectable solar air collectors is too high - mainly across the inlets of the solar air collectors. It should, however, be possible to considerably reduce the pressure losses with a more aerodynamic design of the inlet and outlet of the solar air collectors; The connectable solar air collectors are easy connectable but the air tightness of the connections in the present form is not good enough. As leakage leads to lower efficiencies focus should be put on making the connections more air tight without loosing the easiness in connecting the solar air collectors. As a spin off of the project a simple and easy way to determine the efficiency of solar, air collectors for pre-heating of fresh air has been validated. The simple method of determining the efficiency has with success been compared with an advance method

  8. Solving Environmental Problems

    DEFF Research Database (Denmark)

    Ørding Olsen, Anders; Sofka, Wolfgang; Grimpe, Christoph

    2017-01-01

    for Research and Technological Development (FP7), our results indicate that the problem-solving potential of a search strategy increases with the diversity of existing knowledge of the partners in a consortium and with the experience of the partners involved. Moreover, we identify a substantial negative effect...... dispersed. Hence, firms need to collaborate. We shed new light on collaborative search strategies led by firms in general and for solving environmental problems in particular. Both topics are largely absent in the extant open innovation literature. Using data from the European Seventh Framework Program...

  9. Humanitarian Appeal and the Paradox of Power

    DEFF Research Database (Denmark)

    Vestergaard Jørgensen, Anne

    2013-01-01

    politicization. Some say that humanitarianism is in crisis. This article examines the development of humanitarian advertising through analysis of 124 newspaper ads published in the period from 1970 to 2005. Using a discourse analytical approach which combines institution analysis with multimodal text analysis...... organizations to external demands, in terms of their choice of beneficiaries for public attention and in terms of the symbolic relations they set up between donors and beneficiaries. It is argued that this development is associated with a paradox of power and results in humanitarian organizations surrendering...

  10. Source independence and the EPR paradox

    International Nuclear Information System (INIS)

    Mould, R.A.

    1989-01-01

    It is shown that the lines of action between the photon pairs resulting from a positronium decay are not necessarily in line with the original positronium atom. It is also shown why this 'source-independent' effect is not normally observed, although it is observable in principle. Moreover our initial concerns and some conclusions as they bear on the theory of measurement in quantum mechanics are discussed. Source-independence is shown to give a satisfactory response to a special form of the Einstein-Podolsky-Rosen paradox involving pairs of position measurements. It also leads to a nonlocal relationship between position measurements that depends on the width of the position detectors

  11. Time, physics, and the paradoxes of continuity

    CERN Document Server

    Steinberg, D A

    2003-01-01

    A recent article in this journal proposes a radical reformulation of classical and quantum dynamics based on a perceived deficiency in current definitions of time. The argument is incorrect but the errors highlight aspects of the foundations of mathematics and physics that are commonly confused and misunderstood. For this reason, the article provides an important and heuristic opportunity to reexamine the types of time and non-standard analysis. This paper will discuss the differences between physical time and experiential time and explain how an expanded system of real analysis containing infinitesimals can resolve the paradoxes of continuity without sacrificing the modern edifice of mathematical physics.

  12. Visualizing Statistical Mix Effects and Simpson's Paradox.

    Science.gov (United States)

    Armstrong, Zan; Wattenberg, Martin

    2014-12-01

    We discuss how "mix effects" can surprise users of visualizations and potentially lead them to incorrect conclusions. This statistical issue (also known as "omitted variable bias" or, in extreme cases, as "Simpson's paradox") is widespread and can affect any visualization in which the quantity of interest is an aggregated value such as a weighted sum or average. Our first contribution is to document how mix effects can be a serious issue for visualizations, and we analyze how mix effects can cause problems in a variety of popular visualization techniques, from bar charts to treemaps. Our second contribution is a new technique, the "comet chart," that is meant to ameliorate some of these issues.

  13. Jamaican family structure: the paradox of normalcy.

    Science.gov (United States)

    Dechesnay, M

    1986-06-01

    The relationship between basic research, theory, and clinical work with families is conceptualized during a discussion of Jamaican family structure and the application of change theory to a clinical case of depression in a Jamaican woman. It was found that three types of family structure are prevalent in Jamaica. The European ideal of a patriarchal-patrifocal structure creates problems for working-class Jamaicans. General system theory provides support for a different model. Change theory is applied to resolve the paradox created by the European model.

  14. Paradox of integration-A computational model

    Science.gov (United States)

    Krawczyk, Małgorzata J.; Kułakowski, Krzysztof

    2017-02-01

    The paradoxical aspect of integration of a social group has been highlighted by Blau (1964). During the integration process, the group members simultaneously compete for social status and play the role of the audience. Here we show that when the competition prevails over the desire of approval, a sharp transition breaks all friendly relations. However, as was described by Blau, people with high status are inclined to bother more with acceptance of others; this is achieved by praising others and revealing her/his own weak points. In our model, this action smooths the transition and improves interpersonal relations.

  15. The Paradox of Climate Change Mitigation and Adaptation in Danish Housing

    DEFF Research Database (Denmark)

    Marsh, Rob

    2012-01-01

    that reducing space heating with high levels of thermal insulation and passive solar energy results in overheating and a growing demand for cooling. Climate change is expected to reduce space heating and increase cooling de-mand in housing. An analysis of new build housing using passive solar energy......Climate change means that buildings must greatly reduce their energy consumption. It is however paradoxical that climate mitigation in Denmark has created negative energy and indoor climate problems in housing that may be made worse by climate change. A literature review has been carried out...... of housing schemes where climate mitigation was sought through reduced space heating demand, and it is shown that extensive problems with overheating exist. A theoretical study of regulative and design strategies for climate mitigation in new build housing has therefore been carried out, and it is shown...

  16. Energy paradox and political intervention: A stochastic model for the case of electrical equipments

    International Nuclear Information System (INIS)

    Jridi, Omar; Jridi, Maher; Barguaoui, Saoussen Aguir; Nouri, Fethi Zouheir

    2016-01-01

    This paper develops a model that explains the delay of decisions to adopt profitable energy-saving investments. This problem is known as the energy paradox. The model rationalizes the profitability requirements raised by the irreversibility, the uncertainty and the decrease of costs as a result of learning by doing. In this context, the wait gives investors more visibility and more lower investment costs, which gives them an option value. The representative agent has an interest to postpone its energy saving decision until future benefits increase and equalize its required option value. Formally, we internalize these explanatory factors in a stochastic model where the updated energy saving benefits follows a geometric Brownian motion. To affirm the capacity of the model, we generate simulation results for two equipments for electrical uses. Beyond that, we extend the model to simulate the effects of energy policy instruments to promote adoption of such equipments. Simulations prove that the taxation of energy prices is likely to be more effective than the subsidy for energy-saving equipments. It is also found that the combination of these instruments amplifies the adoption of energy-saving equipments and generates very favorable economic and environmental externalities. - Highlights: •We develop a stochastic model that explains and solves the energy paradox. •Agent postpones the energy-saving investments to maximize its option value. •Option value is fueled by uncertainty, irreversibility and learning by doing. •Subsidies of these investments are less effective than energy taxation. •Mixed instrument policy solves this paradox and generates favorable externalities.

  17. Introspection in Problem Solving

    Science.gov (United States)

    Jäkel, Frank; Schreiber, Cornell

    2013-01-01

    Problem solving research has encountered an impasse. Since the seminal work of Newell und Simon (1972) researchers do not seem to have made much theoretical progress (Batchelder and Alexander, 2012; Ohlsson, 2012). In this paper we argue that one factor that is holding back the field is the widespread rejection of introspection among cognitive…

  18. Solving Linear Differential Equations

    NARCIS (Netherlands)

    Nguyen, K.A.; Put, M. van der

    2010-01-01

    The theme of this paper is to 'solve' an absolutely irreducible differential module explicitly in terms of modules of lower dimension and finite extensions of the differential field K. Representations of semi-simple Lie algebras and differential Galo is theory are the main tools. The results extend

  19. Solving a binary puzzle

    NARCIS (Netherlands)

    Utomo, P.H.; Makarim, R.H.

    2017-01-01

    A Binary puzzle is a Sudoku-like puzzle with values in each cell taken from the set {0,1} {0,1}. Let n≥4 be an even integer, a solved binary puzzle is an n×n binary array that satisfies the following conditions: (1) no three consecutive ones and no three consecutive zeros in each row and each

  20. Electric Current Solves Mazes

    Science.gov (United States)

    Ayrinhac, Simon

    2014-01-01

    We present in this work a demonstration of the maze-solving problem with electricity. Electric current flowing in a maze as a printed circuit produces Joule heating and the right way is instantaneously revealed with infrared thermal imaging. The basic properties of electric current can be discussed in this context, with this challenging question:…

  1. Transport equation solving methods

    International Nuclear Information System (INIS)

    Granjean, P.M.

    1984-06-01

    This work is mainly devoted to Csub(N) and Fsub(N) methods. CN method: starting from a lemma stated by Placzek, an equivalence is established between two problems: the first one is defined in a finite medium bounded by a surface S, the second one is defined in the whole space. In the first problem the angular flux on the surface S is shown to be the solution of an integral equation. This equation is solved by Galerkin's method. The Csub(N) method is applied here to one-velocity problems: in plane geometry, slab albedo and transmission with Rayleigh scattering, calculation of the extrapolation length; in cylindrical geometry, albedo and extrapolation length calculation with linear scattering. Fsub(N) method: the basic integral transport equation of the Csub(N) method is integrated on Case's elementary distributions; another integral transport equation is obtained: this equation is solved by a collocation method. The plane problems solved by the Csub(N) method are also solved by the Fsub(N) method. The Fsub(N) method is extended to any polynomial scattering law. Some simple spherical problems are also studied. Chandrasekhar's method, collision probability method, Case's method are presented for comparison with Csub(N) and Fsub(N) methods. This comparison shows the respective advantages of the two methods: a) fast convergence and possible extension to various geometries for Csub(N) method; b) easy calculations and easy extension to polynomial scattering for Fsub(N) method [fr

  2. On Solving Linear Recurrences

    Science.gov (United States)

    Dobbs, David E.

    2013-01-01

    A direct method is given for solving first-order linear recurrences with constant coefficients. The limiting value of that solution is studied as "n to infinity." This classroom note could serve as enrichment material for the typical introductory course on discrete mathematics that follows a calculus course.

  3. The Neutrosophic Logic View to Schrodinger's Cat Paradox, Revisited

    Directory of Open Access Journals (Sweden)

    Florentin Smarandache

    2008-07-01

    Full Text Available The present article discusses Neutrosophic logic view to Schrodinger's cat paradox. We argue that this paradox involves some degree of indeterminacy (unknown which Neutrosophic logic can take into consideration, whereas other methods including Fuzzy logic cannot. To make this proposition clear, we revisit our previous paper by offering an illustration using modified coin tossing problem, known as Parrondo's game.

  4. Navigating Instructional Dialectics: Empirical Exploration of Paradox in Teaching

    Science.gov (United States)

    Thompson, Blair; Rudick, C. Kyle; Kerssen-Griep, Jeff; Golsan, Kathryn

    2018-01-01

    Navigating contradiction represents an integral part of the teaching process. While educational literature has discussed the paradoxes that teachers experience in the classroom, minimal empirical research has analyzed the strategies teachers employ to address these paradoxes. Using relational dialectics as a theoretical framework for understanding…

  5. Proper-time quantum-mechanics and the Klein paradox

    International Nuclear Information System (INIS)

    Thaller, B.

    1981-01-01

    Scattering at high potential-steps is treated in the framework of relativistic proper-time theory. No paradox arises in contrast to Dirac's wavemechanics (''Klein's paradox''); pair creation may happen with a certain probability and may be described as a scattering process with ordinary quantum-mechanical methods. (author)

  6. Killing Mosquitoes and Keeping Practice: Teacher Education as Sustaining Paradox

    Science.gov (United States)

    Keiser, David Lee

    2013-01-01

    The moral and ethical charge of teaching and teacher education includes sustaining equanimity and paradox, and maintaining poise amongst contradicting policies and interests. This paper draws upon the wisdom of the Tao Te Ching to address some paradoxes in education and teacher preparation. Specifically, the article looks at four chapters of the…

  7. The paradoxes of the interaction-free measurements

    International Nuclear Information System (INIS)

    Vaidman, L.; Tel Aviv Univ.

    2001-01-01

    Interaction-free measurements introduced by Elitzur and Vaidman (1993) allow finding infinitely fragile objects without destroying them. Paradoxical features of these and related measurements are discussed. The resolution of the paradoxes in the framework of the Many-Worlds Interpretation is proposed. (orig.)

  8. Temperature relaxation at the Kapitza-boundary-resistance paradox

    NARCIS (Netherlands)

    Maassen van den Brink, A.; Dekker, H.

    1995-01-01

    The calculation of the Kapitza boundary resistance between dissimilar harmonic solids has for a long time [W. A. Little, Can. J. Phys. 37, 334 (1959)] presented a paradox: this resistance erroneously tends to a finite value in the limit of identical solids. We resolve this paradox by calculating

  9. Galileo's kinematical paradox and the role of resistive forces

    International Nuclear Information System (INIS)

    Aguiar, C E; Soares, V; Tort, A C

    2014-01-01

    We discuss Galileo's kinematical ‘paradox’ taking into account the effects of sliding friction and of resistive forces proportional to velocity. We show that sliding friction eliminates the paradox but still allows for very simple synchronous curves. Perhaps surprisingly, Galileo's paradox is preserved when the resistive force is proportional to velocity. (paper)

  10. A paradox in the global description of the multiverse

    Energy Technology Data Exchange (ETDEWEB)

    Bousso, Raphael [Center for Theoretical Physics, Department of Physics, University of California, Berkeley, CA 94720-7300 (United States); Freivogel, Ben [Center for Theoretical Physics, Department of Physics, University of California, Berkeley, CA 94720-7300 (United States)

    2007-06-15

    We use an argument by Page to exhibit a paradox in the global description of the multiverse: the overwhelming majority of observers arise from quantum fluctuations and not by conventional evolution. Unless we are extremely atypical, this contradicts observation. The paradox does not arise in the local description of the multiverse, but similar arguments yield interesting constraints on the maximum lifetime of metastable vacua.

  11. A paradox in the global description of the multiverse

    International Nuclear Information System (INIS)

    Bousso, Raphael; Freivogel, Ben

    2007-01-01

    We use an argument by Page to exhibit a paradox in the global description of the multiverse: the overwhelming majority of observers arise from quantum fluctuations and not by conventional evolution. Unless we are extremely atypical, this contradicts observation. The paradox does not arise in the local description of the multiverse, but similar arguments yield interesting constraints on the maximum lifetime of metastable vacua

  12. The "Paradox of Interdisciplinarity" in Australian Research Governance

    Science.gov (United States)

    Woelert, Peter; Millar, Victoria

    2013-01-01

    This paper identifies what can be called the "paradox of interdisciplinarity" (Weingart 2000) in Australian higher education research governance and explores some of its constitutive dimensions. In the Australian context, the paradox of interdisciplinarity primarily concerns the proliferation of a programmatic discourse of…

  13. Bolzano's Approach to the Paradoxes of Infinity: Implications for Teaching

    Science.gov (United States)

    Waldegg, Guillermina

    2005-01-01

    In this paper we analyze excerpts of "Paradoxes of the Infinite", the posthumous work of Bernard Bolzano (1781-1848), in order to show that Georg Cantor's (1845-1918) approach to the problem of defining actual mathematical infinity is not the most natural. In fact, Bolzano's approach to the paradoxes of infinity is more intuitive, while remaining…

  14. A Simple Explanation of the Classic Hydrostatic Paradox

    Science.gov (United States)

    Kontomaris, Stylianos-Vasileios; Malamou, Anna

    2016-01-01

    An interesting problem in fluid mechanics, with significant educational importance, is the classic hydrostatic paradox. The hydrostatic paradox states the fact that in different shaped containers, with the same base area, which are filled with a liquid of the same height, the applied force by the liquid on the base of each container is exactly the…

  15. An Applet for the Investigation of Simpson's Paradox

    Science.gov (United States)

    Schneiter, Kady; Symanzik, Jurgen

    2013-01-01

    This article describes an applet that facilitates investigation of Simpson's Paradox in the context of a number of real and hypothetical data sets. The applet builds on the Baker-Kramer graphical representation for Simpson's Paradox. The implementation and use of the applet are explained. This is followed by a description of how the applet has…

  16. Simpson's paradox in psychological science: a practical guide

    NARCIS (Netherlands)

    Kievit, R.A.; Frankenhuis, W.E.; Waldorp, L.J.; Borsboom, D.

    2013-01-01

    The direction of an association at the population-level may be reversed within the subgroups comprising that population—a striking observation called Simpson's paradox. When facing this pattern, psychologists often view it as anomalous. Here, we argue that Simpson's paradox is more common than

  17. Solar Indices - Solar Flares

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Collection includes a variety of indices related to solar activity contributed by a number of national and private solar observatories located worldwide. This...

  18. Solar Indices - Solar Ultraviolet

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Collection includes a variety of indices related to solar activity contributed by a number of national and private solar observatories located worldwide. This...

  19. Solar Indices - Solar Corona

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Collection includes a variety of indices related to solar activity contributed by a number of national and private solar observatories located worldwide. This...

  20. Solar Indices - Solar Irradiance

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Collection includes a variety of indices related to solar activity contributed by a number of national and private solar observatories located worldwide. This...

  1. Toward Solving the Problem of Problem Solving: An Analysis Framework

    Science.gov (United States)

    Roesler, Rebecca A.

    2016-01-01

    Teaching is replete with problem solving. Problem solving as a skill, however, is seldom addressed directly within music teacher education curricula, and research in music education has not examined problem solving systematically. A framework detailing problem-solving component skills would provide a needed foundation. I observed problem solving…

  2. The matchmaking paradox: a statistical explanation

    International Nuclear Information System (INIS)

    Eliazar, Iddo I; Sokolov, Igor M

    2010-01-01

    Medical surveys regarding the number of heterosexual partners per person yield different female and male averages-a result which, from a physical standpoint, is impossible. In this paper we term this puzzle the 'matchmaking paradox', and establish a statistical model explaining it. We consider a bipartite graph with N male and N female nodes (N >> 1), and B bonds connecting them (B >> 1). Each node is associated a random 'attractiveness level', and the bonds connect to the nodes randomly-with probabilities which are proportionate to the nodes' attractiveness levels. The population's average bonds-per-nodes B/N is estimated via a sample average calculated from a survey of size n (n >> 1). A comprehensive statistical analysis of this model is carried out, asserting that (i) the sample average well estimates the population average if and only if the attractiveness levels possess a finite mean; (ii) if the attractiveness levels are governed by a 'fat-tailed' probability law then the sample average displays wild fluctuations and strong skew-thus providing a statistical explanation to the matchmaking paradox.

  3. Parenting paradox: parenting after infant loss.

    Science.gov (United States)

    Warland, Jane; O'Leary, Joann; McCutcheon, Helen; Williamson, Victoria

    2011-10-01

    to gain an in-depth understanding of the parenting experiences of bereaved parents in the years following an infant death. an exploratory qualitative study. semi-structured interview in the participants' homes. Data were collected over a five-month period in 2008 and analysed using thematic analysis. a purposive sample of 13 bereaved parents (10 mothers and three fathers) was used. Parents who had accessed the support services offered by two bereavement support agencies were recruited. Participants were asked to describe their experiences of raising their subsequent child. Interviews were conducted when the next born child was at least three years of age. the parents described a 'paradoxical' parenting style where they were trying to parent using two diametrically opposed unsustainable options. For example, they described trying to hold their subsequent child emotionally close but aloof at the same time. the results from this study indicate that the impact of a loss of an infant has far-reaching consequences on subsequent parenting. Support and early intervention at the time of the stillbirth and subsequent pregnancy are likely to be useful. However, further research is required to determine the extent to which early intervention can alter the tendency towards bereaved parents adopting a paradoxical parenting style. The impact of this style on mental health and the emotional health and well-being of the next born child/ren after perinatal loss should also be further examined. Copyright © 2010 Elsevier Ltd. All rights reserved.

  4. Fermi's Paradox - The Last Challenge For Copernicanism?

    Directory of Open Access Journals (Sweden)

    Ćirković, M. M.

    2009-06-01

    Full Text Available We review Fermi's paradox (or the "Great Silence" problem, not only arguably the oldest and crucial problem for the Search for ExtraTerrestrial Intelligence (SETI, but also a conundrum of profound scientific, philosophical and cultural importance. By a simple analysis of observation selection effects, the correct resolution of Fermi's paradox is certain to tell us something about the future of humanity. Already more than three quarters of century old puzzle -- and a quarter of century since the last major review paper in the field by G. David Brin -- has generated many ingenious discussions and hypotheses. We analyze the often tacit methodological assumptions built in various answers to this puzzle and attempt a new classification of the numerous solutions proposed in an already huge literatureon the subject. Finally, we consider the ramifications of variousclasses of hypotheses for the practical SETI projects. Somewhatparadoxically, it seems that the class of (neocatastrophichypotheses gives, on the balance, the strongest justification tooptimism regarding our current and near-future SETI efforts.

  5. Perspectives on the quantum Zeno paradox

    Science.gov (United States)

    Itano, Wayne M.

    2009-11-01

    As of October 2006, there were approximately 535 citations to the seminal 1977 paper of Misra and Sudarshan that pointed out the quantum Zeno paradox (more often called the quantum Zeno effect). In simple terms, the quantum Zeno effect refers to a slowing down of the evolution of a quantum state in the limit that the state is observed continuously. There has been much disagreement as to how the quantum Zeno effect should be defined and as to whether it is really a paradox, requiring new physics, or merely a consequence of "ordinary" quantum mechanics. The experiment of Itano, Heinzen, Bollinger, and Wineland, published in 1990, has been cited around 347 times and seems to be the one most often called a demonstration of the quantum Zeno effect. Given that there is disagreement as to what the quantum Zeno effect is, there naturally is disagreement as to whether that experiment demonstrated the quantum Zeno effect. Some differing perspectives regarding the quantum Zeno effect and what would constitute an experimental demonstration are discussed.

  6. Perspectives on the quantum Zeno paradox

    International Nuclear Information System (INIS)

    Itano, Wayne M

    2009-01-01

    As of October 2006, there were approximately 535 citations to the seminal 1977 paper of Misra and Sudarshan that pointed out the quantum Zeno paradox (more often called the quantum Zeno effect). In simple terms, the quantum Zeno effect refers to a slowing down of the evolution of a quantum state in the limit that the state is observed continuously. There has been much disagreement as to how the quantum Zeno effect should be defined and as to whether it is really a paradox, requiring new physics, or merely a consequence of 'ordinary' quantum mechanics. The experiment of Itano, Heinzen, Bollinger, and Wineland, published in 1990, has been cited around 347 times and seems to be the one most often called a demonstration of the quantum Zeno effect. Given that there is disagreement as to what the quantum Zeno effect is, there naturally is disagreement as to whether that experiment demonstrated the quantum Zeno effect. Some differing perspectives regarding the quantum Zeno effect and what would constitute an experimental demonstration are discussed.

  7. The Obesity Paradox and Cardiorespiratory Fitness

    Directory of Open Access Journals (Sweden)

    Paul A. McAuley

    2012-01-01

    Full Text Available Cardiorespiratory fitness as an explanation for the obesity paradox warrants further examination. We evaluated independent and joint associations of cardiorespiratory fitness and adiposity with all-cause mortality in 811 middle-aged (age, 53.3±7.2 years male never smokers without documented cardiopulmonary disease or diabetes from the Veterans Exercise Testing Study (VETS. Cardiorespiratory fitness was quantified in metabolic equivalents (METs using final treadmill speed and grade achieved on a maximal exercise test. Subjects were grouped for analysis by METs: unfit (lowest third and fit (upper two-thirds; and by body mass index (kg/m2: nonobese (18.5−29.9 and obese (≥30.0. Associations of baseline fitness and adiposity measures with all-cause mortality were determined by Cox proportional hazards analysis adjusted for age, ethnicity, hypertension, hypercholesterolemia, family history of coronary artery disease, and cardiovascular medication use. In multivariate analysis, mortality risk for obese/fit men did not differ significantly from the nonobese/fit reference group. However, compared to the reference group, nonobese and obese unfit men were 2.2 (=0.01 and 1.9 (=0.03 times more likely to die, respectively. Cardiorespiratory fitness altered the obesity paradox such that mortality risk was lower for both obese and nonobese men who were fit.

  8. Paradox, reprimand and extinction in adults with mental handicap.

    Science.gov (United States)

    Wood, V E; Chamove, A S

    1991-08-01

    To assess the efficacy of paradoxical directives, levels of challenging behaviour during 2 weeks of paradox, reprimand and extinction were compared with baseline levels in four adults with mental handicaps attending a day centre. Paradox was the most effective procedure for reducing the frequency and severity of challenging behaviour by an average of over 70% by the end of 2 weeks and up to 90% in certain subjects; extinction was least effective. Paradox was most effective with more defiant subjects, when staff rated treatment success as low, when improvement using extinction and reprimand was poorest, and in reducing aggressive behaviour. The present authors suggest the overjustification effect offers an explanation for the effects of paradox.

  9. Unveiling consumer's privacy paradox behaviour in an economic exchange.

    Science.gov (United States)

    Motiwalla, Luvai F; Li, Xiao-Bai

    2016-01-01

    Privacy paradox is of great interest to IS researchers and firms gathering personal information. It has been studied from social, behavioural, and economic perspectives independently. However, prior research has not examined the degrees of influence these perspectives contribute to the privacy paradox problem. We combine both economic and behavioural perspectives in our study of the privacy paradox with a price valuation of personal information through an economic experiment combined with a behavioural study on privacy paradox. Our goal is to reveal more insights on the privacy paradox through economic valuation on personal information. Results indicate that general privacy concerns or individual disclosure concerns do not have a significant influence on the price valuation of personal information. Instead, prior disclosure behaviour in specific scenario, like with healthcare providers or social networks, is a better indicator of consumer price valuations.

  10. Observational investigation of the solar oblateness

    International Nuclear Information System (INIS)

    Stebbins, R.T.

    1975-01-01

    The solar oblateness provides important information for solar physics and experimental relativity. After the solar neutrino flux, the sun's shape is the most revealing probe of the solar interior. Rapidly rotating interiors suggested to explain the solar neutrino paradox produce sizeable oblatenesses. Certain types of surface phenomena can also be investigated with precision diameter measurements. The relativistic advance of Mercury's perihelion has long been the principal experimental support for Einstein's theory of general relativity. Recent measurements of the solar oblateness have suggested that the relativistic advance is smaller than originally thought due to a contribution from a solar mass quadrupole moment. This interpretation of the perihelion advance would shift the experimental support to the scalar-tensor theory of gravitation. A debate over the interpretation of the oblateness measurements has resulted. In light of these circumstances, solar oblateness observations have been attempted. Improved experimental techniques have been devised, including a daytime astrometric telescope and an explicit definition of the sun's edge. Observations reveal a time varying excess equatorial brightness, that is, a variation in the limb darkening function between equator and pole, which would preclude accurate interpretation of previous solar oblateness measurements. This vindicates the alternate interpretations of other solar oblateness measurements. From these results, it can be concluded that the Mercury perihelion evidence firmly supports Einstein's General Theory of Relativity, the solar interiors cannot be rotating fast enough to account for the low solar neutrino flux, and a time varying excess equatorial brightness exists

  11. From the BMI paradox to the obesity paradox: the obesity-mortality association in coronary heart disease.

    Science.gov (United States)

    Antonopoulos, A S; Oikonomou, E K; Antoniades, C; Tousoulis, D

    2016-10-01

    Despite a strong association between body weight and mortality in the general population, clinical evidence suggests better clinical outcome of overweight or obese individuals with established coronary heart disease. This finding has been termed the 'obesity paradox', but its existence remains a point of debate, because it is mostly observed when body mass index (BMI) is used to define obesity. Inherent limitations of BMI as an index of adiposity, as well as methodological biases and the presence of confounding factors, may account for the observed findings of clinical studies. In this review, our aim is to present the data that support the presence of a BMI paradox in coronary heart disease and then explore whether next to a BMI paradox a true obesity paradox exists as well. We conclude by attempting to link the obesity paradox notion to available translational research data supporting a 'healthy', protective adipose tissue phenotype. © 2016 World Obesity. © 2016 World Obesity.

  12. Creativity and Problem Solving

    DEFF Research Database (Denmark)

    Vidal, Rene Victor Valqui

    2004-01-01

    This paper presents some modern and interdisciplinary concepts about creativity and creative processes of special relevance for Operational Research workers. Central publications in the area Creativity-Operational Research are shortly reviewed. Some creative tools and the Creative Problem Solving...... approach are also discussed. Finally, some applications of these concepts and tools are outlined. Some central references are presented for further study of themes related to creativity or creative tools....

  13. Creativity and problem Solving

    Directory of Open Access Journals (Sweden)

    René Victor Valqui Vidal

    2004-12-01

    Full Text Available This paper presents some modern and interdisciplinary concepts about creativity and creative processes of special relevance for Operational Research workers. Central publications in the area Creativity-Operational Research are shortly reviewed. Some creative tools and the Creative Problem Solving approach are also discussed. Finally, some applications of these concepts and tools are outlined. Some central references are presented for further study of themes related to creativity or creative tools.

  14. Solar neutrino problem

    Energy Technology Data Exchange (ETDEWEB)

    Faulkner, D J [Australian National Univ., Canberra. Mount Stromlo and Siding Spring Observatories

    1975-10-01

    This paper reviews several recent attempts to solve the problem in terms of modified solar interior models. Some of these have removed the count rate discrepancy, but have violated other observational data for the sun. One successfully accounts for the Davis results at the expense of introducing an ad hoc correction with no current physical explanation. An introductory description of the problem is given.

  15. Geochemical and biologic constraints on the Archaean atmosphere and climate – A possible solution to the faint early Sun paradox

    DEFF Research Database (Denmark)

    Rosing, Minik Thorleif; Brid, Dennis K.; Sleep, Norman H.

    into account the apparent growth of Earth continents (Collerson and Kamber 1999) and the absence of land vegetation during the Precambrian for the evolution of the surface albedo, and a model for the abundance and properties of clouds that takes into account the lower abundance of biogenic cloud condensation......There is ample geological evidence that Earth’s climate resembled the present during the Archaean, despite a much lower solar luminosity. This was cast as a paradox by Sagan and Mullen in 1972. Several solutions to the paradox have been suggested, mostly focusing on adjustments of the radiative...... properties of Earth’s atmosphere e.g. Kasting (1993), by increasing the mixing ratio of CO2 and/or adding various other greenhouse gasses. We have used banded iron formation (BIF), which are chemical sediments precipitated out of the Archaean ocean to characterize the composition of the atmosphere...

  16. Educating geographers in an era of the anthropocene: paradoxical natures - paradoxical cultures

    DEFF Research Database (Denmark)

    Grindsted, Thomas Skou

    2015-01-01

    Geographical imaginations are vital to make sense of challenges to sustainability which are produced and distributed across scale. Yet, a number of studies find that geography has been reluctant to integrate sustainability issues in its curricula. Geography is particularly interesting and can con...... of this finding is significant across disciplines. Thus, scholars and students should learn to go beyond the geopolitics of education in order to transcend the paradoxical-culture-natures identified...

  17. Simpson’s Paradox in Psychological Science: A Practical Guide

    Directory of Open Access Journals (Sweden)

    Rogier eKievit

    2013-08-01

    Full Text Available The direction of an association at the population-level may be reversed within the subgroups comprising that population—a striking observation called Simpson’s paradox. When facing this pattern, psychologists often view it as anomalous. Here, we argue that Simpson’s paradox is more common than conventionally thought, and typically results in incorrect interpretations – potentially with harmful consequences. We support this claim by drawing on empirical results from cognitive neuroscience, behavior genetics, psychopathology, personality psychology, educational psychology, intelligence research, and simulation studies. We show that Simpson’s Paradox is most likely to occur when inferences are drawn across different levels of explanation (e.g., from populations to subgroups, or subgroups to individuals. We propose a set of statistical markers indicative of the paradox, and offer psychometric solutions for dealing with the paradox when encountered—including a toolbox in R for detecting Simpson’s Paradox. We show that explicit modeling of situations in which the paradox might occur not only prevents incorrect interpretations of data, but also results in a deeper understanding of what data tell us about the world.

  18. The periodontal pain paradox: Difficulty on pain assesment in dental patients (The periodontal pain paradox hypothesis

    Directory of Open Access Journals (Sweden)

    Haryono Utomo

    2006-12-01

    Full Text Available In daily dental practice, the majority of patients’ main complaints are related to pain. Most patients assume that all pains inside the oral cavity originated from the tooth. One particular case is thermal sensitivity; sometimes patients were being able to point the site of pain, although there is neither visible caries nor secondary caries in dental radiograph. In this case, gingival recession and dentin hypersensitivity are first to be treated to eliminate the pain. If these treatments failed, pain may misdiagnose as pulpal inflammation and lead to unnecessary root canal treatment. Study in pain during periodontal instrumentation of plaque-related periodontitis revealed that the majority of patients feel pain and discomfort during probing and scaling. It seems obvious because an inflammation, either acute or chronic is related to a lowered pain threshold. However, in contrast, in this case report, patient suffered from chronic gingivitis and thermal sensitivity experienced a relative pain-free sensation during probing and scaling. Lowered pain threshold which accompanied by a blunted pain perception upon periodontal instrumentation is proposed to be termed as the periodontal pain paradox. The objective of this study is to reveal the possibility of certain factors in periodontal inflammation which may involved in the periodontal pain paradox hypothesis. Patient with thermal hypersensitivity who was conducted probing and scaling, after the relative pain-free instrumentation, thermal hypersensitivity rapidly disappeared. Based on the successful periodontal treatment, it is concluded that chronic gingivitis may modulate periodontal pain perception which termed as periodontal pain paradox

  19. Cosmic time dilation: The clock paradox revisited

    International Nuclear Information System (INIS)

    Tomaschitz, Roman

    2004-01-01

    The relativistic time dilation is reviewed in a cosmological context. We show that a clock or twin paradox does not arise if cosmic time is properly taken into account. The receding galaxy background provides a unique frame of reference, and the proper times of geodesic as well as accelerated observers can be linked to the universal cosmic time parameter. This suggests to compare the proper time differentials of the respective observers by determining their state of motion in the galaxy grid. In this way, each observer can figure out whether his proper time is dilated or contracted relative to any other. In particular one can come to unambiguous conclusions on the aging of uniformly moving observers, without reference to asymmetries in measurement procedures or accelerations they may have undergone

  20. Paradoxes and Opportunities in Logistic Outsourcing Research

    Directory of Open Access Journals (Sweden)

    Đurđica Stojanović

    2012-11-01

    Full Text Available Historically, very few logistic trends have caught the attention of academics and practitioners to the same extent as outsourcing. A comprehensive literature review reveals two reasons for this continual topicality. The problem complexity and the business environment dynamics – including an interaction with other main trends in logistics and modern supply chains – both led to a permanent literature gap, indicating the need to explore some new aspects of logistics outsourcing (LO. In this paper, a new LO research perspective has been explored by identifying some weaknesses in the main LO research streams and related common viewpoints which led to six ‘logistics outsourcing research paradoxes’. Each of these paradoxes is briefly described and their links with research streams and common views on LO discussed. Finally, the nature of some known opportunities for further research is better explained and some overlooked research opportunities are highlighted.

  1. Twin paradox in de Sitter spacetime

    International Nuclear Information System (INIS)

    Boblest, Sebastian; Wunner, Guenter; Mueller, Thomas

    2011-01-01

    The 'twin paradox' of special relativity offers the possibility of making interstellar flights within a lifetime. For very long journeys with velocities close to the speed of light, however, we have to take into account the expansion of the universe. Inspired by the work of Rindler on hyperbolic motion in curved spacetime, we study the worldline of a uniformly accelerated observer in de Sitter spacetime and the communication between the travelling observer and an observer at rest. This paper is intended to give graduate students who are familiar with special relativity and have some basic experience of general relativity a deeper insight into accelerated motion in general relativity, into the relationship between the proper times of different observers and the propagation of light signals between them, and into the use of compactification to describe the global structure of a relativistic model.

  2. HIV As Trojan Exosome: Immunological Paradox Explained?

    Science.gov (United States)

    Hildreth, James E K

    2017-01-01

    The HIV pandemic is still a major global challenge, despite the widespread availability of antiretroviral drugs. An effective vaccine would be the ideal approach to bringing the pandemic to an end. However, developing an effective HIV vaccine has proven to be an elusive goal. Three major human HIV vaccine trials revealed a strong trend toward greater risk of infection among vaccine recipients versus controls. A similar observation was made in a macaque SIV vaccine study. The mechanism explaining this phenomenon is not known. Here, a model is presented that may explain the troubling results of vaccine studies and an immunological paradox of HIV pathogenesis: preferential infection of HIV-specific T cells. The central hypothesis of this perspective is that as "Trojan exosomes" HIV particles can directly activate HIV-specific T cells enhancing their susceptibility to infection. Understanding the biology of HIV as an exosome may provide insights that enable novel approaches to vaccine development.

  3. [Euthanasia and the paradoxes of autonomy].

    Science.gov (United States)

    Siqueira-Batista, Rodrigo; Schramm, Fermin Roland

    2008-01-01

    The principle of respect for autonomy has proved very useful for bioethical arguments in favor of euthanasia. However unquestionable its theoretical efficacy, countless aporiae can be raised when conducting a detailed analysis of this concept, probably checkmating it. Based on such considerations, this paper investigates the principle of autonomy, starting with its origins in Greek and Christian traditions, and then charting some of its developments in Western cultures through to its modern formulation, a legacy of Immanuel Kant. The main paradoxes of this concept are then presented in the fields of philosophy, biology, psychoanalysis and politics, expounding several of the theoretical difficulties to be faced in order to make its applicability possible within the scope of decisions relating to the termination of life.

  4. Aging and communication in the twin paradox

    International Nuclear Information System (INIS)

    De Wolf, David A

    2016-01-01

    The twin paradox of the special theory of relativity has given rize to a large body of literature discussing its implications. In its standard form, the traveler changes velocity only at the destination of the trip, so that he appears to perceive an improbably instantaneous and non-continuous change in age of the stationary twin. In this work, a smooth velocity/acceleration profile is used that allows the abrupt velocity-change case as a limit. All gravitational effects are ignored in this treatment. Aside from mutual perception of simultaneous clock times in an accelerating frame, constant communication of clock times between the twins by means of (digital) light signals is shown to be possible, in principle if not in practice. (paper)

  5. Partial Actions, Paradoxicality and Topological full Groups

    DEFF Research Database (Denmark)

    Scarparo, Eduardo

    uniform Roe algebra is finite. In Article C, we analyze the C*-algebra generated by the Koopman representation of a topological full group, showing, in particular, that it is not AF andhas real rank zero. We also prove that if G is a finitely generated, elementary amenable group, and C*(G) has real rank......We study how paradoxicality properties affect the way groups partially acton topological spaces and C*-algebras. We also investigate the real rank zero and AF properties for certain classes of group C*-algebras. Specifically, in article A, we characterize supramenable groups in terms of existence...... of invariant probability measures for partial actions on compact Hausdorff spaces and existence of tracial states on partial crossed products. These characterizations show that, in general, one cannot decompose a partial crossed product of a C*-algebra by a semidirect product of groups as two iterated...

  6. Cannabinoid Hyperemesis Syndrome: A Paradoxical Cannabis Effect

    Directory of Open Access Journals (Sweden)

    Ivonne Marie Figueroa-Rivera

    2015-01-01

    Full Text Available Despite well-established antiemetic properties of marijuana, there has been increasing evidence of a paradoxical effect in the gastrointestinal tract and central nervous system, given rise to a new and underrecognized clinical entity called the Cannabinoid Hyperemesis Syndrome. Reported cases in the medical literature have established a series of patients exhibiting a classical triad of symptoms: cyclic vomiting, chronic marijuana use, and compulsive bathing. We present a case of a 29-year-old man whose clinical presentation strongly correlates with cannabinoid hyperemesis syndrome. Despite a diagnosis of exclusion, this syndrome should be considered plausible in the setting of a patient with recurrent intractable vomiting and a strong history of cannabis use as presented in this case.

  7. Explaining mutualism variation: a new evolutionary paradox?

    Science.gov (United States)

    Heath, Katy D; Stinchcombe, John R

    2014-02-01

    The paradox of mutualism is typically framed as the persistence of interspecific cooperation, despite the potential advantages of cheating. Thus, mutualism research has tended to focus on stabilizing mechanisms that prevent the invasion of low-quality partners. These mechanisms alone cannot explain the persistence of variation for partner quality observed in nature, leaving a large gap in our understanding of how mutualisms evolve. Studying partner quality variation is necessary for applying genetically explicit models to predict evolution in natural populations, a necessary step for understanding the origins of mutualisms as well as their ongoing dynamics. An evolutionary genetic approach, which is focused on naturally occurring mutualist variation, can potentially synthesize the currently disconnected fields of mutualism evolution and coevolutionary genetics. We outline explanations for the maintenance of genetic variation for mutualism and suggest approaches necessary to address them. © 2013 The Author(s). Evolution © 2013 The Society for the Study of Evolution.

  8. EPR paradox, quantum nonlocality and physical reality

    International Nuclear Information System (INIS)

    Kupczynski, M

    2016-01-01

    Eighty years ago Einstein, Podolsky and Rosen demonstrated that instantaneous reduction of wave function, believed to describe completely a pair of entangled physical systems, led to EPR paradox. The paradox disappears in statistical interpretation of quantum mechanics (QM) according to which a wave function describes only an ensemble of identically prepared physical systems. QM predicts strong correlations between outcomes of measurements performed on different members of EPR pairs in far-away locations. Searching for an intuitive explanation of these correlations John Bell analysed so called local realistic hidden variable models and proved that correlations consistent with these models satisfy Bell inequalities which are violated by some predictions of QM and by experimental data. Several different local models were constructed and inequalities proven. Some eminent physicists concluded that Nature is definitely nonlocal and that it is acting according to a law of nonlocal randomness. According to these law perfectly random, but strongly correlated events, can be produced at the same time in far away locations and a local and causal explanation of their occurrence cannot be given. We strongly disagree with this conclusion and we prove the contrary by analysing in detail some influential finite sample proofs of Bell and CHSH inequalities and so called Quantum Randi Challenges. We also show how one can win so called Bell's game without violating locality of Nature. Nonlocal randomness is inconsistent with local quantum field theory, with standard model in elementary particle physics and with causal laws and adaptive dynamics prevailing in the surrounding us world. The experimental violation of Bell-type inequalities does not prove the nonlocality of Nature but it only confirms a contextual character of quantum observables and gives a strong argument against counterfactual definiteness and against a point of view according to which experimental outcomes are

  9. EPR paradox, quantum nonlocality and physical reality

    Science.gov (United States)

    Kupczynski, M.

    2016-03-01

    Eighty years ago Einstein, Podolsky and Rosen demonstrated that instantaneous reduction of wave function, believed to describe completely a pair of entangled physical systems, led to EPR paradox. The paradox disappears in statistical interpretation of quantum mechanics (QM) according to which a wave function describes only an ensemble of identically prepared physical systems. QM predicts strong correlations between outcomes of measurements performed on different members of EPR pairs in far-away locations. Searching for an intuitive explanation of these correlations John Bell analysed so called local realistic hidden variable models and proved that correlations consistent with these models satisfy Bell inequalities which are violated by some predictions of QM and by experimental data. Several different local models were constructed and inequalities proven. Some eminent physicists concluded that Nature is definitely nonlocal and that it is acting according to a law of nonlocal randomness. According to these law perfectly random, but strongly correlated events, can be produced at the same time in far away locations and a local and causal explanation of their occurrence cannot be given. We strongly disagree with this conclusion and we prove the contrary by analysing in detail some influential finite sample proofs of Bell and CHSH inequalities and so called Quantum Randi Challenges. We also show how one can win so called Bell's game without violating locality of Nature. Nonlocal randomness is inconsistent with local quantum field theory, with standard model in elementary particle physics and with causal laws and adaptive dynamics prevailing in the surrounding us world. The experimental violation of Bell-type inequalities does not prove the nonlocality of Nature but it only confirms a contextual character of quantum observables and gives a strong argument against counterfactual definiteness and against a point of view according to which experimental outcomes are produced

  10. A "refugee paradox" for substance use disorders?

    Science.gov (United States)

    Salas-Wright, Christopher P; Vaughn, Michael G

    2014-09-01

    Few, if any, studies have systematically examined the link between nativity and substance use disorders (SUD) among refugees using national samples. As such, it remains uncertain if the "immigrant paradox" for substance use can be extended to include refugees in the United States. Employing data from the National Epidemiologic Survey on Alcohol and Related Conditions, we examine the lifetime prevalence of SUDs among refugees (n=428) in contrast with non-refugee immigrants (n=4955) and native-born Americans (n=29,267). We also examine the impact of gender and refugee duration on the relationship between nativity, refugee status, and SUDs. Refugees were between 3 and 6 times less likely than native-born Americans meet criteria for all SUDs examined, and significantly less likely than non-refugee immigrants to meet criteria for alcohol (AOR=0.44, 95% CI=0.41-0.47), cocaine (AOR=0.54, 95% CI=0.50-0.59), hallucinogen (AOR=0.66, 95% CI=0.58-0.74), and opioid/heroin (AOR=0.62, 95% CI=0.58-0.66) use disorders. The refugee-SUD link was significantly moderated by gender. Duration as a refugee was associated with increased risk for alcohol use disorder and decreased risk of cannabis and illicit drug use disorders. Study findings provide evidence in support of a "refugee paradox" for SUDs among adults in the United States. Refugees are substantially less likely than native-born Americans to meet criteria for all SUDs examined and, albeit with weaker effects, significantly less likely than non-refugee immigrants to meet criteria for a variety of SUDs. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  11. DDT and Malaria Prevention: Addressing the Paradox

    Science.gov (United States)

    Bouwman, Hindrik; van den Berg, Henk; Kylin, Henrik

    2011-01-01

    Background The debate regarding dichlorodiphenyltrichloroethane (DDT) in malaria prevention and human health is polarized and can be classified into three positions: anti-DDT, centrist-DDT, pro-DDT. Objective We attempted to arrive at a synthesis by matching a series of questions on the use of DDT for indoor residual spraying (IRS) with literature and insights, and to identify options and opportunities. Discussion Overall, community health is significantly improved through all available malaria control measures, which include IRS with DDT. Is DDT “good”? Yes, because it has saved many lives. Is DDT safe as used in IRS? Recent publications have increasingly raised concerns about the health implications of DDT. Therefore, an unqualified statement that DDT used in IRS is safe is untenable. Are inhabitants and applicators exposed? Yes, and to high levels. Should DDT be used? The fact that DDT is “good” because it saves lives, and “not safe” because it has health and environmental consequences, raises ethical issues. The evidence of adverse human health effects due to DDT is mounting. However, under certain circumstances, malaria control using DDT cannot yet be halted. Therefore, the continued use of DDT poses a paradox recognized by a centrist-DDT position. At the very least, it is now time to invoke precaution. Precautionary actions could include use and exposure reduction. Conclusions There are situations where DDT will provide the best achievable health benefit, but maintaining that DDT is safe ignores the cumulative indications of many studies. In such situations, addressing the paradox from a centrist-DDT position and invoking precaution will help design choices for healthier lives. PMID:21245017

  12. The paradoxes of the consumer society

    Directory of Open Access Journals (Sweden)

    A. N. Il’In

    2016-01-01

    Full Text Available The article describes two characteristic of the consumer society of the paradox. The first is expressed in the contradiction between the desire for himself by exposure to high consumer standards and constraints of a financial nature. Specifics of consumer culture requires to make demonstrative waste of money, even if it is associated with financial resources. Demonstrative waste of money exercise by savings on invisible to others spheres of life, as “message” on the status becomes more important need than the satisfaction of these needs. The relationship between income and consumption does not seem unambiguous. Updated trend of the sense of consumption goods, pseudoconsumerism, realizing the need to seem - one of fictitious needs, which in practice translates into implementation of strategy is symbolic of deception. There is a “fictitious second order”, which is not associated with the symbolic meaning of a certain good, and with the symbolic meaning of goods, which is not cash, but is missing. Consumption has shifted imitating under the consumption of performance, consumption of simulacrum and virtuality. The dichotomy of “to have or to be” in this case is replaced by the dichotomy of “to have or to pass” and, in turn, “to pass or to be”. The second paradox is expressed in cultivating the desire to emphasize with consumption individuality that goes away when the practice becomes mass. Standardization is carried out under the rhetoric about elitism. The samples on offer as elitist, their attractiveness ascribe to itself the masses. It’s elitist by material unavailable to most people, but the mass by the desire of many people to be attached to them. Characteristic of a consumer society fashion consciously orients a select minority, but the underlying basis remains unconscious orientation to universality. Fashion stimulating consumption standards and to the implementation of individual choice, which constrained by these

  13. Paradoxical embolism: Experiences from a single center

    Directory of Open Access Journals (Sweden)

    Hong-Liang Zhang

    2017-06-01

    Full Text Available Objective: To present our treatment experiences and the follow-up data of patients with paradoxical embolism (PDE. Methods: The clinical characteristics, management, and follow-up data of all included patients who were diagnosed with PDE at Fuwai Hospital from January 1994 to October 2015 were recorded. Results: Twelve patients were included; all had a pulmonary embolism, and 8 had deep venous thrombosis. The artery embolisms involved the cerebral artery (7 patients, renal artery (2 patients, mesentery artery (2 patients, popliteal artery (1 patient, descending aorta thrombus (1 patient, and thrombus-straddled patent foramen ovale (PFO (1 patient. PFO was found in 3 cases. One patient underwent thrombectomy and PFO closure; Six patients received thrombolysis; and 3 patients were implanted with a vena cava filter. Long-term anticoagulation with warfarin was recommended for each patient. One patient died from ventricular fibrillation despite cardiopulmonary resuscitation. Eleven patients were discharged with improvements. No late mortality occurred in 8 patients with a complete follow-up of 10.6–17.7 years. One had a recurrent deep venous thrombosis. No patient had a recurrent pulmonary or arterial embolism. Two patients changed their treatment from warfarin to aspirin; others remained on warfarin. Only 1 case had an occasional gum bleeding. Conclusions: PDE treatment including thrombolysis, anticoagulation, and embolectomy should be individualized. We recommend long-term anticoagulation therapy to prevent the recurrence of PDE, especially to those with an intracardiac communication or persistent risk factors for re-thrombosis. Keywords: Paradoxical embolism, Pulmonary embolism, Deep venous thrombosis, Patent foramen ovale

  14. Simpson's paradox: A statistician's case study.

    Science.gov (United States)

    Chu, Kevin H; Brown, Nathan J; Pelecanos, Anita; Brown, Anthony Ft

    2018-02-26

    Gender equality and workforce diversity has recently been in the forefront of College discussions. Reasons for the difference between various groups may not be as they initially appeared. The results of comparing the outcome between two groups can sometimes be confounded and even reversed by an unrecognised third variable. This concept is known as Simpson's Paradox, and is illustrated here using a renowned case study on potential gender bias for acceptance to Graduate School at the University of California, Berkeley.  The investigation showed that males were 1.8 times more likely to be admitted to Graduate School than females in 1973. Initially it appeared that women were discriminated against in the selection process. However, when admissions were re-examined at individual Departments of the School, admission tended to be better for women than men in four of six Departments. This contradiction or paradox tells us that the association between admission and gender was dependent upon on Department.  The confounding effect of Department was defined by two characteristics. Firstly, a strong association between Department and admission: some Departments admitted much smaller percentages of applicants than others. Secondly, a strong association between Department and gender: females tended to apply to Departments with lower admission rates.  The explanation of differences between groups can be multifactorial. A search for possible confounders will assist in this understanding. This could apply whenever two groups initially appear to differ, but on closer analysis this difference is either unfounded, or even reversed by reference to a third, confounding variable. © 2018 Australasian College for Emergency Medicine and Australasian Society for Emergency Medicine.

  15. Linear optics implementation of weak values in Hardy's paradox

    International Nuclear Information System (INIS)

    Ahnert, S.E.; Payne, M.C.

    2004-01-01

    We propose an experimental setup for the implementation of weak measurements in the context of the gedanken experiment known as Hardy's paradox. As Aharonov et al. [Y. Aharonov, A. Botero, S. Popescu, B. Reznik, and J. Tollaksen, Phys. Lett. A301, 130 (2002)] showed, these weak values form a language with which the paradox can be resolved. Our analysis shows that this language is indeed consistent and experimentally testable. It also reveals exactly how a combination of weak values can give rise to an apparently paradoxical result

  16. On the Mathematics of the Jeffreys-Lindley Paradox

    OpenAIRE

    Villa, Cristiano; Walker, Stephen

    2015-01-01

    This paper is concerned with the well known Jeffreys-Lindley paradox. In a Bayesian set up, the so-called paradox arises when a point null hypothesis is tested and an objective prior is sought for the alternative hypothesis. In particular, the posterior for the null hypothesis tends to one when the uncertainty, i.e. the variance, for the parameter value goes to infinity. We argue that the appropriate way to deal with the paradox is to use simple mathematics, and that any philosophical argumen...

  17. Women's understanding of the "Nice guy paradox": a phenomenological study

    OpenAIRE

    2010-01-01

    M.A. The Nice Guy Paradox is a provocative perception that is commonly expressed within society and the mass media. According to this perception, nice guys are less successful in their relationships with women than other men. The Nice Guy Paradox causes much frustration and confusion for self-proclaimed nice guys. In addition, the implications of this perception may negatively influence the way in which men relate to women. For instance, the Nice Guy Paradox implies that if men want to be ...

  18. Linear perspective and framing in the vista paradox

    DEFF Research Database (Denmark)

    Costa, Marco; Bonetti, Leonardo

    2017-01-01

    The vista paradox is the illusion in which an object seen through a frame appears to shrink in apparent size as the observer approaches the frame. In four studies, we tested the effect of framing and fixating on the target object. The first two studies assessed the vista paradox in a large scale...... inserted within five frames differing in size. In the fourth study linear perspective was added to the images. The results showed that both frame size and linear perspective cues were critical factors for the vista paradox illusion....

  19. Solar building

    OpenAIRE

    Zhang, Luxin

    2014-01-01

    In my thesis I describe the utilization of solar energy and solar energy with building integration. In introduction it is also mentioned how the solar building works, trying to make more people understand and accept the solar building. The thesis introduces different types of solar heat collectors. I compared the difference two operation modes of solar water heating system and created examples of solar water system selection. I also introduced other solar building applications. It is conv...

  20. Appreciative Problem Solving

    DEFF Research Database (Denmark)

    Hansen, David

    2012-01-01

    Many industrial production work systems have increased in complexity, and their new business model scompete on innovation, rather than low cost.At a medical device production facility committed to Lean Production, a research project was carried out to use Appreciative Inquiry to better engage...... employee strengths in continuou simprovements of the work system. The research question was: “How can Lean problem solving and Appreciative Inquiry be combined for optimized work system innovation?” The research project was carried out as a co-creation process with close cooperation between researcher...

  1. Simon on problem solving

    DEFF Research Database (Denmark)

    Foss, Kirsten; Foss, Nicolai Juul

    2006-01-01

    as a general approach to problem solving. We apply these Simonian ideas to organisational issues, specifically new organisational forms. Specifically, Simonian ideas allow us to develop a morphology of new organisational forms and to point to some design problems that characterise these forms.......Two of Herbert Simon's best-known papers are 'The Architecture of Complexity' and 'The Structure of Ill-Structured Problems.' We discuss the neglected links between these two papers, highlighting the role of decomposition in the context of problems on which constraints have been imposed...

  2. Planning and Problem Solving

    Science.gov (United States)

    1982-10-01

    Artificial Intelig ~ence (Vol. III, edited by Paul R. Cohen and’ Edward A.. Feigenbaum)’, The chapter was written B’ Paul Cohen, with contributions... Artificial Intelligence (Vol. III, edited by Paul R. Cohen and EdWard A. Feigenbaum). The chapter was written by Paul R. Cohen, with contributions by Stephen...Wheevoats"EntermdI’ Planning and Problem ’Solving by Paul R. Cohen Chaptb-rXV-of Volumec III’of the Handbook of Artificial Intelligence edited by Paul R

  3. Solar energy

    International Nuclear Information System (INIS)

    Anon.

    1992-01-01

    This chapter discusses the role solar energy may have in the energy future of the US. The topics discussed in the chapter include the solar resource, solar architecture including passive solar design and solar collectors, solar-thermal concentrating systems including parabolic troughs and dishes and central receivers, photovoltaic cells including photovoltaic systems for home use, and environmental, health and safety issues

  4. Solving Differential Equations in R: Package deSolve

    Science.gov (United States)

    In this paper we present the R package deSolve to solve initial value problems (IVP) written as ordinary differential equations (ODE), differential algebraic equations (DAE) of index 0 or 1 and partial differential equations (PDE), the latter solved using the method of lines appr...

  5. Solving Differential Equations in R: Package deSolve

    NARCIS (Netherlands)

    Soetaert, K.E.R.; Petzoldt, T.; Setzer, R.W.

    2010-01-01

    In this paper we present the R package deSolve to solve initial value problems (IVP) written as ordinary differential equations (ODE), differential algebraic equations (DAE) of index 0 or 1 and partial differential equations (PDE), the latter solved using the method of lines approach. The

  6. Importance of Tourism Paradox, Tourism Equinox and Tourism Detox for Urban Environments

    Directory of Open Access Journals (Sweden)

    Arikan Irfan

    2016-12-01

    Full Text Available When looking at the increase of tourism in a destination, it can be said that tourism is a valuable part of the economy. The proposal offered by today’s competitive paradigm: that higher the number of tourists visiting a city, the higher the income, sounds good at first. The increased number of tourist arrivals gives the appearance of increasing desirability of the city. Parallel with the increased tourism activities, new buildings, new lifestyles, foreign capital and new socio-economic relationships appear rapidly and replace the traditional ones. However, there will be a huge amount of social, cultural, economic and environmental problems faced by the local people as well as the tourists the city. Tourism paradox is the name given to the phenomenon where tourism industry destroys natural and cultural environment in a destination that is necessary for tourism activities. On the other hand the balance, which does not change and disturbs the social and economic relations at the destination is called “tourism equinox”. Therefore, spatial reorganization and urban regeneration play a crucial role for the marketing of cities and this transformation action affects all infrastructure facilities, restorations of old buildings, reorganization of historical zones, and revitalizing the architectural style of the cities. New projects and approaches to solve the problems caused by the growth of urban populations and to establish healthy sustainable tourism destinations are becoming more important than ever. Tourism detox is a treatment that is intended to remove harmful substances from these destinations. This paper investigates the influence of tourism paradox and tourism equinox on urban environments in relation to tourism activities and the protection of natural and cultural resources with the help of tourism detox. It primarily relies on qualitative research to understand the main futures of tourism paradox, equinox and detox taking the physical

  7. Ending the myth of the St Petersburg Paradox

    Directory of Open Access Journals (Sweden)

    Robert Vivian

    2013-09-01

    Full Text Available Nicolas Bernoulli suggested the St Petersburg game, nearly 300 years ago, which is widely believed to produce a paradox in decision theory. This belief stems from a long standing mathematical error in the original calculation of the expected value of the game. This article argues that, in addition to the mathematical error, there are also methodological considerations which gave rise to the paradox. This article explains these considerations and why because of the modern computer, the same considerations, when correctly applied, also demonstrate that no paradox exists. Because of the longstanding belief that a paradox exists it is unlikely the mere mathematical correction will end the myth. The article explains why it is the methodological correction which will dispel the myth.

  8. Pervasive Technologies and the Paradoxes of Multimodal Digital Communication

    Directory of Open Access Journals (Sweden)

    Sandra Petroni

    2014-12-01

    Full Text Available Contemporary societies are greatly challenged by paradoxes in all facets of life. Digital communication encodes and produces meaning by making use of these contradictory relations. In this contribution, three digital paradoxes will be presented. The first paradox is grounded in the process of remediation in digital settings which mirrors a contradictory double logic. Digital culture, in fact, wants both to multiply its media and to eliminate all traces of mediation. The second antinomy has its origins in the new concept of linguistic entropy: a structured information disorder that is regulated by usability and multimodality. In accordance with the second paradox, the third one stems from further processes that are framing, a multimodal resource, and linking, a hypertextual resource.

  9. Paradoxical perception of surfaces in the Shepard tabletop illusion

    Science.gov (United States)

    Tyler, Christopher W

    2011-01-01

    The Shepard tabletop illusion, consisting of different perspective embeddings of two identical parallelograms as tabletops, affords a profound difference in their perceived surface shapes. My analysis reveals three further paradoxical aspects of this illusion, in addition to its susceptibility to the ‘inverse perspective illusion’ of the implied orthographic perspective of the table images. These novel aspects of the illusion are: a paradoxical slant of the tabletops, a paradoxical lack of perceived depth, and a paradoxical distortion of the length of the rear legs. The construction of the illusion resembles scenes found in ancient Chinese scroll paintings, and an analysis of the source of the third effect shows that the interpretation in terms of surfaces can account for the difference in treatment of the filled-in versus open forms in the Chinese painting from more than 1000 years ago. PMID:23145230

  10. Intimate partner violence against women and the Nordic paradox.

    Science.gov (United States)

    Gracia, Enrique; Merlo, Juan

    2016-05-01

    Nordic countries are the most gender equal countries in the world, but at the same time they have disproportionally high prevalence rates of intimate partner violence (IPV) against women. High prevalence of IPV against women, and high levels of gender equality would appear contradictory, but these apparently opposite statements appear to be true in Nordic countries, producing what could be called the 'Nordic paradox'. Despite this paradox being one of the most puzzling issues in the field, this is a research question rarely asked, and one that remains unanswered. This paper explores a number of theoretical and methodological issues that may help to understand this paradox. Efforts to understand the Nordic paradox may provide an avenue to guide new research on IPV and to respond to this major public health problem in a more effective way. Copyright © 2016 Elsevier Ltd. All rights reserved.

  11. Greenberger-Horne-Zeilinger paradoxes from qudit graph states.

    Science.gov (United States)

    Tang, Weidong; Yu, Sixia; Oh, C H

    2013-03-08

    One fascinating way of revealing quantum nonlocality is the all-versus-nothing test due to Greenberger, Horne, and Zeilinger (GHZ) known as the GHZ paradox. So far genuine multipartite and multilevel GHZ paradoxes are known to exist only in systems containing an odd number of particles. Here we shall construct GHZ paradoxes for an arbitrary number (greater than 3) of particles with the help of qudit graph states on a special kind of graphs, called GHZ graphs. Furthermore, based on the GHZ paradox arising from a GHZ graph, we derive a Bell inequality with two d-outcome observables for each observer, whose maximal violation attained by the corresponding graph state, and a Kochen-Specker inequality testing the quantum contextuality in a state-independent fashion.

  12. One-Piece Faraday Generator: A Paradoxical Experiment from 1851

    Science.gov (United States)

    Crooks, M. J.; And Others

    1978-01-01

    Describes an experiment based on Faraday's one-piece generator, where the rotating disk is replaced by a cylindrical permanent magnet. Explains the apparent paradox that an observer in an inertial frame could measure his absolute velocity. (GA)

  13. A Zeno-like paradox in linear interaction

    International Nuclear Information System (INIS)

    Weiss, J.

    1998-01-01

    The so-called Zeno-like paradox of infinite regressions and progressions connected by light cones, typical to particle dynamics of direct-interaction (ADD) theory, is examined for linear AAD interaction. It is shown that the paradox is resolved via convenient evaluating integral expressions which determine conserved quantities of Lorentz group to exhibit integral-free forms. As a result the formalism is also permitted to emerge the field confinement as one of substantial properties of linear interaction. (author)

  14. The klein paradox as a many particle problem

    International Nuclear Information System (INIS)

    Bongaarts, P.J.M.; Ruijsenaars, S.N.M.

    1976-01-01

    A mathematically rigorous analysis of the Klein paradox is given in the many-particle formulation of the Dirac theory. This paradox was meant as an example demonstrating the negative energy problems of the single particle Dirac equation. However, it is shown that this problem does not disappear in the second quantized version of the Dirac theory. It corresponds with a situation which cannot be described properly within the framework of a field theory with an external potential

  15. On the present status of the Klein Paradox

    International Nuclear Information System (INIS)

    Wergeland, H.

    1980-01-01

    Klein's paradox is a solution of Dirac's equation which implies that electrons may penetrate an electrostatic potential barrier even when their kinetic energy is lower than the barrier. Since the barrier is infinitely broad this is not a case of tunneling. A number of treatments of the paradox, by Sauter, Hylleraas, Jenssen and others are discussed, and the Boundary Value Problem is treated at some length. Examples are presented with an infinitely broad barrier and with a barrier of finite breadth. (JIW)

  16. "Paradox fikce" a emoce ve sportovních filmech

    OpenAIRE

    Sýkora, Matěj

    2013-01-01

    This bachelor thesis deals with the paradox of fiction and emotion of recipients of sports films. The work is divided into four main chapters. The first two aim to define the key terms fiction (the fictional world) and emotion. The third chapter briefly summarizes the most important theories dealing with the paradox of fiction (Radford and Weston, Walton, etc.) and offers an outline of a possible solution to the problem following neurobiological explorations of Antonio Damasio and selected co...

  17. Moving towards a geocentric, polycultural theory of organizational paradox

    OpenAIRE

    Keller, J.; Lewis, M. W.

    2016-01-01

    Purpose\\ud This paper comments on “Global implications of the indigenous epistemological system from the east” (Li, 2016), which provides an indigenous Chinese perspective on organizational paradox. Li introduces Yin-Yang balancing as an epistemological system that can help scholars examine and practitioners manage paradoxes. In this commentary, the purpose of this paper is to discuss the merits of Yin-Yang balancing and how this approach and other indigenous theories might enrich organizatio...

  18. Governance and Developing Asia: Concepts, Measurements, Determinants, and Paradoxes

    OpenAIRE

    Quibria, M.G.

    2014-01-01

    Recent years have seen the emergence of a considerable volume of literature on governance and its role in economic and social development of a country. This paper provides a critical review of the literature. This review brings into the open a number of serious conceptual, measurement, and data issues as well as the existence of an Asian governance paradox - i.e., a general disjunction between growth and governance in most Asian economies. This paradox seems to suggest that much of the curren...

  19. Extensitivity of entropy and modern form of Gibbs paradox

    International Nuclear Information System (INIS)

    Home, D.; Sengupta, S.

    1981-01-01

    The extensivity property of entropy is clarified in the light of a critical examination of the entropy formula based on quantum statistics and the relevant thermodynamic requirement. The modern form of the Gibbs paradox, related to the discontinuous jump in entropy due to identity or non-identity of particles, is critically investigated. Qualitative framework of a new resolution of this paradox, which analyses the general effect of distinction mark on the Hamiltonian of a system of identical particles, is outlined. (author)

  20. The Schroedinger's paradox and the tranformation of quantum systems

    International Nuclear Information System (INIS)

    Bitsakis, E.I.

    1980-01-01

    The Schroedinger's paradox is analysed, as an illustration of certain weaknesses of the Copenhagen's interpretation of quantum mechanics and of the limits of the quantum-mechanical description of phenomena. A realistic approach of the paradox indicates the necessity of a theory that would permit not only the calculation of probabilities, but also the description of physical processes, as taking place in space and time

  1. Paradoxical response to dexamethasone and spontaneous hypocortisolism in Cushing's disease

    OpenAIRE

    Lila, Anurag R; Sarathi, Vijaya; Bandgar, Tushar R; Shah, Nalini S

    2013-01-01

    Paradoxical response to dexamethasone and spontaneous development of hypocortisolism are rare features of Cushing's disease. We report a 13-year-old boy with Cushing's disease owing to a pituitary macroadenoma. On initial evaluation, he had partial suppression of serum cortisol by dexamethasone. He developed transient hypocortisolism after first adenomectomy, but the disease recurred after 1 year. Repeat evaluation showed recurrent hypercortisolism and paradoxical response to dexamethasone. H...

  2. Solved problems in electromagnetics

    CERN Document Server

    Salazar Bloise, Félix; Bayón Rojo, Ana; Gascón Latasa, Francisco

    2017-01-01

    This book presents the fundamental concepts of electromagnetism through problems with a brief theoretical introduction at the beginning of each chapter. The present book has a strong  didactic character. It explains all the mathematical steps and the theoretical concepts connected with the development of the problem. It guides the reader to understand the employed procedures to learn to solve the exercises independently. The exercises are structured in a similar way: The chapters begin with easy problems increasing progressively in the level of difficulty. This book is written for students of physics and engineering in the framework of the new European Plans of Study for Bachelor and Master and also for tutors and lecturers. .

  3. Solved problems in electrochemistry

    International Nuclear Information System (INIS)

    Piron, D.L.

    2004-01-01

    This book presents calculated solutions to problems in fundamental and applied electrochemistry. It uses industrial data to illustrate scientific concepts and scientific knowledge to solve practical problems. It is subdivided into three parts. The first uses modern basic concepts, the second studies the scientific basis for electrode and electrolyte thermodynamics (including E-pH diagrams and the minimum energy involved in transformations) and the kinetics of rate processes (including the energy lost in heat and in parasite reactions). The third part treats larger problems in electrolysis and power generation, as well as in corrosion and its prevention. Each chapter includes three sections: the presentation of useful principles; some twenty problems with their solutions; and, a set of unsolved problems

  4. How to Avoid Fragility of Financial Systems: Lessons from the Financial Crisis and St. Petersburg Paradox

    Science.gov (United States)

    Takayasu, Hideki

    Firstly, I point out that the financial crisis occurred in 2008 has many analogous points with a physical phenomenon of brittle fracture in the sense that it is a highly irreversible phenomenon caused by concentration of stress to the weakest point. Then, I discuss distribution of gain-loss of continuous transactions of options which can be regarded as a source of stress among financial companies. The historical problem of Saint Petersburg paradox is reviewed and it is argued that the paradox is solved by decomposing the process into a combination of a fair gamble and an accompanied financial option. By generalizing this fair gamble it is shown that the gain-loss distribution in this problem is closely related to the distribution of gain-loss of business firms in the real world. Finally, I pose a serious question to the ordinary way of financing money to business firms with compound interest rates. Instead we introduce a new way of financing business firms without applying prefixed interest rates, in which financial stress is shared by all involved firms. This method is expected to reduce the risk of both financial firms and business firms, and is applicable even in the non-growing society.

  5. Limits of policy intervention in a world of neoliberal mechanism designs: Paradoxes of the global crisis

    Directory of Open Access Journals (Sweden)

    Dymski Gary A.

    2011-01-01

    Full Text Available The current global context poses several paradoxes: the recovery from the 2009 recession was not a recovery; investment, normally driven by profit rates, is lagging and not leading economic activity; the crisis is global but debate involves sub-global levels; and public safety-nets, which have helped to stabilize national income, are being cut. These paradoxes can be traced, in part, to the impact of the “truce” that followed the Keynesian-Monetarist controversy on economists’ ideas about policy activism. This implicit “truce” has removed activist macro policy from discussion, and shifted attention toward institutions as mechanisms for solving game-theoretic coordination problems. Policy activism then centers on how the “agents” (nations can achieve optimal use of their available resources (or optimal access to resources at the global level; and this involves creating and fine-tuning compacts - neoliberal mechanism designs - that can capture rents and attract globally mobile capital. This approach leads economists to see the key problem in the current global crisis as fixing broken neoliberal mechanisms. However, a global economy dominated by mechanisms that feed on aggregate demand without generating it faces the prospect of stagnation or collapse.

  6. Middle ground approach to paradox: Within- and between-culture examination of the creative benefits of paradoxical frames.

    Science.gov (United States)

    Leung, Angela K-Y; Liou, Shyhnan; Miron-Spektor, Ella; Koh, Brandon; Chan, David; Eisenberg, Roni; Schneider, Iris

    2018-03-01

    Thriving in increasingly complex and ambiguous environments requires creativity and the capability to reconcile conflicting demands. Recent evidence with Western samples has suggested that paradoxical frames, or mental templates that encourage individuals to recognize and embrace contradictions, could produce creative benefits. We extended the timely, but understudied, topic by studying the nuances of for whom and why creative advantages of paradoxical frames emerge. We suggest that people endorsing a middle ground approach are less likely to scrutinize conflict and reconcile with integrative solutions, thus receiving less creative benefits of paradoxical frames. Five studies that examined individual and cultural differences in middle ground endorsement support our theory. Study 1 found that paradoxical frames increased creativity, but failed to replicate that experienced conflict mediated the relationship in a Taiwanese sample. In both within- and between-culture analysis, we showed that the creative advantages of thinking paradoxically and experiencing conflict emerged among individuals who endorse lower (vs. higher) levels of middle ground (Study 2) and among Israelis whose culture predominantly endorses middle ground strategy less, but not among Singaporeans whose culture predominantly endorses middle ground more (Study 3). Study 4 further demonstrated the causal role of middle ground in the paradox-conflict-creativity link. To answer "why," Study 5 situationally induced integrative complex thinking that sets distinctions and forms syntheses among contradictory elements, and found that low endorsers of middle ground performed more creatively when they engaged integrative complex thinking to cope with paradoxes. This program of studies offers important insights on harnessing paradoxical experiences to catalyze creativity. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

  7. The paradox of transmission system value

    International Nuclear Information System (INIS)

    Haddad, S.Z.; Feldman, R.D.; Charnetzki, P.

    1995-01-01

    The central importance of utility strategic planning with respect to transmission systems has developed as a result of the passage of the Energy Policy Act and the rapid emergence of the era of open grid access. As a consequence, utilities have had to redefine transmission as being more than a cost center managed with reliability as the principal focus and regulated on a rate of return basis. Transmission must now be managed with a view to protection of customers, where possible, and to revenue maximization, both through pricing strategy and through operations. This shift has been compounded by the pressures being thrust upon utilities by regulators or being fomented by competitors to unbundle transmission and distribution from generation. This paper explores how the value of the transmission system can be viewed from the vantage points of different organizations (utilities, regulators, customers, independent generators, etc.). The paper addresses the uncertain and apparently paradoxical nature of transmission system value as it will be impacted by the possible alternative future structures of the electric power industry. Lastly, this paper suggests the strategic possibilities for utilities that this uncertainty presents

  8. Aristotle vs. Plato: The Balkans' Paradoxical Enlightenment

    Directory of Open Access Journals (Sweden)

    D. Michalopoulos

    2007-09-01

    Full Text Available As it occurred in West, Aristotle’s thought was in Byzantium the main organon of philosophical meditation within the frame of the Christian Faith. Nonetheless, from the ninth century on it was a revival of Platonism that took place – of Neo-Platonism at the beginning and of Platonism itself at the end. The Church, initially indifferent, became suspicious only when, at the turning of the fourteenth to the fifteenth century, the Platonism seemed to engender somewhat a latent paganism; but the Patriarchate was not then able to fight that tendency. So only after the 1453 capture of Constantinople by the Ottomans, Gennadius Scholarius managed to root out from the Greek lands Platonism and its crypto-pagan extension. Be that as it may; the main paradox of the Balkan history is that in the early seventeenth century some leading Greek scholars endorsed the materialist interpretation of Aristotle’s thought – as it was taught in the University of Padua by Cesare Cremonini; and as a corollary this materialistic philosophical system began being taught in both Constantinople and Athens. It was that very way that the Enlightenment took birth in the Balkans – and somehow became a State ideology - long before its prevalence in France. And of course all this had as a result a turn toward Physics and Chemistry with far-reaching consequences

  9. First evidence for "The backup plan paradox".

    Science.gov (United States)

    Napolitano, Christopher M; Freund, Alexandra M

    2017-08-01

    This research is a first test of the backup plan paradox. We hypothesized that investing in a backup plan may facilitate the conditions that it was developed to address: Plan A's insufficiency. Five studies provide initial, primarily correlative support for the undermining effect of investing in a backup plan. Study 1 (n= 160) demonstrated that the more participants perceived they had invested in developing a backup plan (preparing a "crib sheet"), the more likely they were to use it, although greater investments were unrelated to backup plan utility. Studies 2-4 used a simulated negotiation task. Study 2 (n = 247) demonstrated that when goal-relevant resources are limited, investing in developing backup plans and perceiving them as highly instrumental can decrease goal performance through the indirect effect of increased means replacing. Study 3 (n = 248) replicated this effect when goal-relevant resources were plentiful. Study 4 (n = 204) used an experimental variant of the simulated negotiation task and demonstrated that simply having a backup plan is not detrimental, but perceiving backup plans to be highly instrumental decreased goal performance, again through the indirect effect of increased means replacing. Study 5 (n = 160) replicated findings from Studies 1-4 using a lab-based motor task (throwing a ball). Together, these results provide first evidence that backup plans can introduce costs that may jeopardize goal performance. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  10. The Paradox of Leisure in Later Life

    Science.gov (United States)

    Nimrod, Galit; Shrira, Amit

    2016-01-01

    Objective. Numerous studies have shown that involvement in leisure activity has a significant impact on older adults’ physical, psychological, social, and spiritual well-being. This study explores whether the association between leisure involvement and well-being in later life changes over time. Method. Data were drawn from the first 4 waves of the Survey of Health, Ageing, and Retirement in Europe (SHARE). Growth curve models were applied to examine whether leisure moderated change in quality of life (QoL) over time among 7,875 retirees aged 60 and older. Results. Findings indicated that the association between leisure and QoL increased with time, as nonactive respondents displayed a decline in QoL over time, whereas those with high levels of leisure involvement showed an increase. Findings remained significant after controlling for sociodemographics, health, and cognitive functioning. Discussion. Results indicated that the significance of leisure to well-being increases throughout the later life course, and that leisure may act as a resource for resilience in old age. They also pointed out a paradoxical situation in which the older seniors, who may benefit from leisure involvement more than their younger peers, are precisely the ones who face the greater number of constraints to beneficial use of leisure. PMID:25315158

  11. Marketing human organs: the autonomy paradox.

    Science.gov (United States)

    Marshall, P A; Thomasma, D C; Daar, A S

    1996-03-01

    The severe shortage of organs for transplantation and the continual reluctance of the public to voluntarily donate has prompted consideration of alternative strategies for organ procurement. This paper explores the development of market approaches for procuring human organs for transplantation and considers the social and moral implications of organ donation as both a "gift of life" and a "commodity exchange." The problematic and paradoxical articulation of individual autonomy in relation to property rights and marketing human body parts is addressed. We argue that beliefs about proprietorship over human body parts and the capacity to provide consent for organ donation are culturally constructed. We contend that the political and economic framework of biomedicine, in western and non-western nations, influences access to transplantation technology and shapes the form and development of specific market approaches. Finally, we suggest that marketing approaches for organ procurement are and will be negotiated within cultural parameters constrained by several factors: beliefs about the physical body and personhood, religious traditions, economic conditions, and the availability of technological resources.

  12. Exploratory shaft conceptual design report: Paradox Basin

    International Nuclear Information System (INIS)

    1983-07-01

    This conceptual design report summarizes the conceptualized design for an exploratory shaft facility at a representative site in the Paradox Basin located in the southeastern part of Utah. Conceptualized designs for other possible locations (Permian Basin in Texas and Gulf Interior Region salt domes in Louisiana and Mississippi) are summarized in separate reports. The purpose of the exploratory shaft facility is to provide access to the reference repository horizon to permit in situ testing of the salt. The in-situ testing is necessary to verify repository salt design parameters, evaluate isotropy and homogeneity of the salt, and provide a demonstration of the constructability and confirmation of the design to gain access to the repository. The fundamental purpose of this conceptual design report is to assure the feasibility of the exploratory shaft project and to develop a reliable cost estimate and realistic schedule. Because a site has not been selected and site-specific subsurface data are not available, it has been necessary to make certain assumptions in order to develop a conceptual design for an exploratory shaft facility in salt. As more definitive information becomes available to support the design process, adjustments in the projected schedule and estimated costs will be required

  13. [Dream in the land of paradoxical sleep].

    Science.gov (United States)

    Pire, E; Herman, G; Cambron, L; Maquet, P; Poirrier, R

    2008-01-01

    Paradoxical sleep (PS or REM sleep) is traditionally a matter for neurophysiology, a science of the brain. Dream is associated with neuropsychology and sciences of the mind. The relationships between sleep and dream are better understood in the light of new methodologies in both domains, particularly those of basic neurosciences which elucidate the mechanisms underlying SP and functional imaging techniques. Data from these approaches are placed here in the perspective of rather old clinical observations in human cerebral lesions and in the phylogeny of vertebrates, in order to support a theory of dream. Dreams may be seen as a living marker of a cognitivo-emotional process, called here "eidictic process", involving posterior brain and limbic structures, keeping up during wakefulness, but subjected, at that time, to the leading role of a cognitivo-rational process, called here "thought process". The last one is of instrumental origin in human beings. It involves prefrontal cortices (executive tasks) and frontal/parietal cortices (attention) in the brain. Some clinical implications of the theory are illustrated.

  14. Hydrostatic Paradox: Experimental Verification of Pressure Equilibrium

    Science.gov (United States)

    Kodejška, C.; Ganci, S.; Ríha, J.; Sedlácková, H.

    2017-01-01

    This work is focused on the experimental verification of the balance between the atmospheric pressure acting on the sheet of paper, which encloses the cylinder completely or partially filled with water from below, where the hydrostatic pressure of the water column acts against the atmospheric pressure. First of all this paper solves a theoretical…

  15. An attempt at solving the problem of autocorrelation associated with use of mean approach for pooling cross-section and time series in regression modelling

    International Nuclear Information System (INIS)

    Nuamah, N.N.N.N.

    1990-12-01

    The paradoxical nature of results of the mean approach in pooling cross-section and time series data has been identified to be caused by the presence in the normal equations of phenomena such as autocovariances, multicollinear covariances, drift covariances and drift multicollinear covariances. This paper considers the problem of autocorrelation and suggests ways of solving it. (author). 4 refs

  16. Pebble Puzzle Solved

    Science.gov (United States)

    2004-01-01

    [figure removed for brevity, see original site] Figure 1 In the quest to determine if a pebble was jamming the rock abrasion tool on NASA's Mars Exploration Rover Opportunity, scientists and engineers examined this up-close, approximate true-color image of the tool. The picture was taken by the rover's panoramic camera, using filters centered at 601, 535, and 482 nanometers, at 12:47 local solar time on sol 200 (August 16, 2004). Colored spots have been drawn on this image corresponding to regions where panoramic camera reflectance spectra were acquired (see chart in Figure 1). Those regions are: the grinding wheel heads (yellow); the rock abrasion tool magnets (green); the supposed pebble (red); a sunlit portion of the aluminum rock abrasion tool housing (purple); and a shadowed portion of the rock abrasion tool housing (brown). These spectra demonstrated that the composition of the supposed pebble was clearly different from that of the sunlit and shadowed portions of the rock abrasion tool, while similar to that of the dust-coated rock abrasion tool magnets and grinding heads. This led the team to conclude that the object disabling the rock abrasion tool was indeed a martian pebble.

  17. Solar energy: Technology and applications

    Science.gov (United States)

    Williams, J. R.

    1974-01-01

    It is pointed out that in 1970 the total energy consumed in the U.S. was equal to the energy of sunlight received by only 0.15% of the land area of the continental U.S. The utilization of solar energy might, therefore, provide an approach for solving the energy crisis produced by the consumption of irreplaceable fossil fuels at a steadily increasing rate. Questions regarding the availability of solar energy are discussed along with the design of solar energy collectors and various approaches for heating houses and buildings by utilizing solar radiation. Other subjects considered are related to the heating of water partly or entirely with solar energy, the design of air conditioning systems based on the use of solar energy, electric power generation by a solar thermal and a photovoltaic approach, solar total energy systems, industrial and agricultural applications of solar energy, solar stills, the utilization of ocean thermal power, power systems based on the use of wind, and solar-energy power systems making use of geosynchronous power plants.

  18. Quantum Bayesian networks with application to games displaying Parrondo's paradox

    Science.gov (United States)

    Pejic, Michael

    Bayesian networks and their accompanying graphical models are widely used for prediction and analysis across many disciplines. We will reformulate these in terms of linear maps. This reformulation will suggest a natural extension, which we will show is equivalent to standard textbook quantum mechanics. Therefore, this extension will be termed quantum. However, the term quantum should not be taken to imply this extension is necessarily only of utility in situations traditionally thought of as in the domain of quantum mechanics. In principle, it may be employed in any modelling situation, say forecasting the weather or the stock market---it is up to experiment to determine if this extension is useful in practice. Even restricting to the domain of quantum mechanics, with this new formulation the advantages of Bayesian networks can be maintained for models incorporating quantum and mixed classical-quantum behavior. The use of these will be illustrated by various basic examples. Parrondo's paradox refers to the situation where two, multi-round games with a fixed winning criteria, both with probability greater than one-half for one player to win, are combined. Using a possibly biased coin to determine the rule to employ for each round, paradoxically, the previously losing player now wins the combined game with probabilitygreater than one-half. Using the extended Bayesian networks, we will formulate and analyze classical observed, classical hidden, and quantum versions of a game that displays this paradox, finding bounds for the discrepancy from naive expectations for the occurrence of the paradox. A quantum paradox inspired by Parrondo's paradox will also be analyzed. We will prove a bound for the discrepancy from naive expectations for this paradox as well. Games involving quantum walks that achieve this bound will be presented.

  19. SOHO hunts elusive solar prey

    Science.gov (United States)

    1995-10-01

    , or crown; this outermost layer of the solar atmosphere extends to the planets and beyond. The solar corona is extremely hot, with a temperature of a few million degrees. Its very existence is one of the most fundamental, unresolved paradoxes of modern solar physics. The photosphere is closer to the Sun's centre than the corona, but it is several hundred times cooler. Heat should not flow outward from a cooler to a hotter region; it violates common sense and the second law of thermodynamics. Despite more than a half century of investigation, the exact mechanism for heating corona still remains a mystery, and it is one of the main scientific objectives of the SOHO mission. Sunlight passes right through the corona without depositing substantial quantities of energy in it. So, radiation cannot resolve the heating problem. Possible mechanisms involve the kinetic energy of moving material and/or magnetic energy. Unlike radiation, both of these forms of energy can flow from cold to hot regions. In and out motions within the solar interior within the solar interior generate sound waves that could accelerate into supersonic shocks; they apparently dissipate energy and generate heat in the lower chromosphere. However, observations suggest that sound waves cannot significantly heat the corona since they cannot reach that far. SOHO will test this conclusion, looking for the varying spectral signatures of sound waves in the chromosphere and corona. Magnetic energy should play a role in coronal heating. Magnetic fields shape the highly structured corona, and the brightest coronal structures are located where the magnetic field is the strongest. SOHO's spectral instruments will therefore also look for the oscillating intensity and velocity signatures of magnetic waves that are produced by changing magnetism. Magnetic energy can also be converted into heat by numerous small, localised explosive events that have already been observed with space-borne telescopes at ultraviolet

  20. Solar Features - Solar Flares

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A solar flare is a short-lived sudden increase in the intensity of radiation emitted in the neighborhood of sunspots. For many years it was best monitored in the...

  1. Probabilistic sharing solves the problem of costly punishment

    Science.gov (United States)

    Chen, Xiaojie; Szolnoki, Attila; Perc, Matjaž

    2014-08-01

    Cooperators that refuse to participate in sanctioning defectors create the second-order free-rider problem. Such cooperators will not be punished because they contribute to the public good, but they also eschew the costs associated with punishing defectors. Altruistic punishers—those that cooperate and punish—are at a disadvantage, and it is puzzling how such behaviour has evolved. We show that sharing the responsibility to sanction defectors rather than relying on certain individuals to do so permanently can solve the problem of costly punishment. Inspired by the fact that humans have strong but also emotional tendencies for fair play, we consider probabilistic sanctioning as the simplest way of distributing the duty. In well-mixed populations the public goods game is transformed into a coordination game with full cooperation and defection as the two stable equilibria, while in structured populations pattern formation supports additional counterintuitive solutions that are reminiscent of Parrondo's paradox.

  2. Solar storms; Tormentas solares

    Energy Technology Data Exchange (ETDEWEB)

    Collaboration: Pereira Cuesta, S.; Pereira Pagan, B.

    2016-08-01

    Solar storms begin with an explosion, or solar flare, on the surface of the sun. The X-rays and extreme ultraviolet radiation from the flare reach the Earths orbit minutes later-travelling at light speed. The ionization of upper layers of our atmosphere could cause radio blackouts and satellite navigation errors (GPS). Soon after, a wave of energetic particles, electrons and protons accelerated by the explosion crosses the orbit of the Earth, and can cause real and significant damage. (Author)

  3. Developing solar: PV solar system markets in Africa

    International Nuclear Information System (INIS)

    Asali, Karim

    2002-01-01

    Governments, NGO's and UN organisations are increasingly convinced that renewable energies not only help to solve energy problems in Africa but are indispensable in alleviating regional disparities, social problems and bridging the digital gap. Still, many years after introducing high efficiency solar PV systems the necessary breakthrough of implementing them on a mass scale is still not a reality. The author provides perspectives on developing solar PV in Africa. (Author)

  4. Toward High-Performance Communications Interfaces for Science Problem Solving

    Science.gov (United States)

    Oviatt, Sharon L.; Cohen, Adrienne O.

    2010-12-01

    From a theoretical viewpoint, educational interfaces that facilitate communicative actions involving representations central to a domain can maximize students' effort associated with constructing new schemas. In addition, interfaces that minimize working memory demands due to the interface per se, for example by mimicking existing non-digital work practice, can preserve students' attentional focus on their learning task. In this research, we asked the question: What type of interface input capabilities provide best support for science problem solving in both low- and high- performing students? High school students' ability to solve a diverse range of biology problems was compared over longitudinal sessions while they used: (1) hardcopy paper and pencil (2) a digital paper and pen interface (3) pen tablet interface, and (4) graphical tablet interface. Post-test evaluations revealed that time to solve problems, meta-cognitive control, solution correctness, and memory all were significantly enhanced when using the digital pen and paper interface, compared with tablet interfaces. The tangible pen and paper interface also was the only alternative that significantly facilitated skill acquisition in low-performing students. Paradoxically, all students nonetheless believed that the tablet interfaces provided best support for their performance, revealing a lack of self-awareness about how to use computational tools to best advantage. Implications are discussed for how pen interfaces can be optimized for future educational purposes, and for establishing technology fluency curricula to improve students' awareness of the impact of digital tools on their performance.

  5. The animal fat paradox and meat quality.

    Science.gov (United States)

    Webb, E C; O'Neill, H A

    2008-09-01

    The purpose of this paper is to address some of the paradoxical issues and perceptions regarding animal fats and the related effects on meat quality and consumer perceptions. Meat scientists have been studying carcass characteristics for many years and although the factors that influence the accumulation, distribution and composition of carcass fat in livestock have been extensively researched, the role, value and perceptions of animal fats in meat quality differ significantly in importance between producers, abattoirs, butchers, retailers and consumers. Fat and long-chain fatty acids, whether in adipose tissue or muscle, contribute to important aspects of meat quality and are central to the nutritional and sensory values of meat. In this review the nutritional value of fat, as well as the importance of fat in terms of carcass and meat quality will be highlighted. The 'quality' of meat depends greatly on the socio-demographic backgrounds of the consumer. The aim is to focus on the global importance of fat in the carcass to the producer, processor and consumer. There is currently no clear cut definition for fat quality because the acceptability and perceived quality of fat varies significantly in terms of quantity, colour, consistency and chemical composition in different species of livestock around the world. The association between animal fats and human health is critical and recommendations by health professionals range from excluding fats altogether to a moderate consumption of fats due to their essential role in the body. Recently the emphasis has shifted away from fat quantity to fat quality. Despite these recommendations and years of bad publicity in terms of the adverse affects of animal fats in human health, the livestock industry seems reluctant to shift its focus to fat quality rather than quantity. This approach may adversely affect future meat consumption by consumers who are becoming increasingly critical about the food they eat.

  6. Resolving the paradox of suboptimal choice.

    Science.gov (United States)

    Zentall, Thomas R

    2016-01-01

    When humans engage in commercial (totally probabilistic) gambling they are making suboptimal choices because the return is generally less than the investment. This review (a) examines the literature on pigeon suboptimal choice, (b) describes the conditions under which it occurs, (c) identifies the mechanisms that appear to be responsible for the effect, and (d) suggests that similar processes may be able to account for analogous suboptimal choice when humans engage in commercial gambling. Pigeons show suboptimal choice when they choose between 1 alternative that 20% of the time provides them with a signal that they will always get fed or 80% of the time with a signal that they will not get fed (overall 20% reinforcement) and a second alternative that 100% of the time provides them with a signal that they will get fed 50% of the time (overall 50% reinforcement). The pigeons' strong preference for the suboptimal choice was investigated in a series of experiments that found the preference for the suboptimal alternative was determined by the value of the signal that predicted reinforcement, rather its frequency and that the frequency of the signal that predicted nonreinforcement had little effect on the suboptimal choice. Paradoxically, this account makes the prediction that pigeons will be indifferent between an alternative that 50% of the time provides a fully predictive stimulus for reinforcement and an alternative that 100% of the time provides a fully predictive stimulus for reinforcement. The similarities and differences of this suboptimal choice task to human gambling are discussed. (c) 2016 APA, all rights reserved).

  7. Embolia paradojal inminente Impending paradoxical embolism

    Directory of Open Access Journals (Sweden)

    Miguel A. Veltri

    2006-12-01

    Full Text Available La presencia de un trombo venoso atrapado en un defecto interauricular e insinuándose en las cavidades izquierdas configura una forma extremadamente inusual de enfermedad tromboembólica denominada embolia paradojal inminente. Presentamos el caso de un varón de 71 años, sometido 10 días antes a adenomectomía prostática, que consultó por disnea y mareos. Se le diagnosticó tromboembolismo pulmonar bilateral por tomografía axial computada helicoidal. Se lo anticoaguló con heparina sódica y se le realizó un ecocardiograma transesofágico que mostró un trombo que atravesaba el foramen oval y se alojaba en la aurícula izquierda. No presentaba signos clínicos de embolización sistémica. Se realizó la embolectomía quirúrgica y cierre del defecto auricular. El paciente falleció.An intracardiac thrombus traversing a patent foramen ovale is a very infrequent but potentially catastrophic complication of the thromboembolic disease. It is named "impending paradoxical embolism". We report the case of a 71 year old Caucasian male warded in ten days after a prostatectomy because of bilateral pulmonary embolism. Diagnosis was confirmed by HCT scan and the patient received anticoagulation with heparin. A transesophageal ecocardiogram disclosed a thrombus traversing foramen ovale into the left atrium. Surgical embolectomy was performed, but the patient died shortly after surgery.

  8. Where Was Everybody? Olaf Stapledon and the Fermi Paradox

    Science.gov (United States)

    Baxter, S.

    In 1948 Olaf Stapledon gave an address to the BIS in which he summarised his vision of mankind's cosmic future: `One can imagine some sort of cosmical community of worlds ...' One might ask, however, since the universe is vastly older than mankind, why races on other worlds have not already built such a community. This is a `Fermi Paradox' question. The Paradox is based on the observation that there has been time for extraterrestrial intelligence to arise and colonise the Galaxy many times over, yet we see no sign of such endeavours. In this paper Stapledon's novels are retrospectively analysed from the point of view of the Fermi Paradox. In Last and First Men (1930) humanity is forever isolated because life and mind are rare in the Galaxy, and interstellar distances are too large ever to be traversed. These are classic candidate Fermi `solutions'. The `solution' implicit in Star Maker (1937) might be criticised in that it posits that humanity lives at a special epoch, with the cosmically transforming development of interstellar travel occurring a `mere' ten billion years after mankind, in a universe supposedly ~200bn years old. Stapledon died in 1950, the year the Paradox was formulated, and was probably unaware of the Paradox. However to apply retrospectively Fermi thinking to Stapledon's cosmologies is to gain a new insight into the author's philosophy.

  9. Explaining the evaporation paradox in Jiangxi Province of China: Spatial distribution and temporal trends in potential evapotranspiration of Jiangxi Province from 1961 to 2013

    Directory of Open Access Journals (Sweden)

    Xianghui Lu

    2016-03-01

    Full Text Available Evaporation acts as an important component and a key control factor in land hydrological processes. In order to analyze the trend of change on potential evapotranspiration from 1961 to 2013 and to discuss the existence of the evaporation paradox in Jiangxi province, China, monthly meteorological data spanning the years 1961–2013 were analyzed in this study, where the data were collected from 15 national meteorological stations in Jiangxi Province. The Penman–Monteith equation was employed to compute the potential evapotranspiration (ET0. Spatial interpolation and data mining technology were used to analyze the spatial and temporal changes of ET0 and air temperature, with the effort to explain the evaporation paradox. By solving the total differential and the partial derivatives coefficients of the independent variables in Penman–Monteith equation, the cause of the paradox was quantitatively evaluated. The results showed that the annual ET0 had been decreasing significantly in Jiangxi Province since 1979, whereas the air temperature had been rising significantly, presenting the evaporation paradox. The decreases in sunshine duration and wind speed reduced ET0 by 0.207 mm and 0.060 mm, respectively, accounting for 92.3% and 26.7% of the total ET0, respectively. It is concluded that sunshine duration and wind speed are the main causes to the decrease in potential evapotranspiration in Jiangxi Province.

  10. Einstein-Podolsky-Rosen paradox in single pairs of images.

    Science.gov (United States)

    Lantz, Eric; Denis, Séverine; Moreau, Paul-Antoine; Devaux, Fabrice

    2015-10-05

    Spatially entangled twin photons provide a test of the Einstein-Podolsky-Rosen (EPR) paradox in its original form of position (image plane) versus impulsion (Fourier plane). We show that recording a single pair of images in each plane is sufficient to safely demonstrate an EPR paradox. On each pair of images, we have retrieved the fluctuations by subtracting the fitted deterministic intensity shape and then have obtained an intercorrelation peak with a sufficient signal to noise ratio to safely distinguish this peak from random fluctuations. A 95% confidence interval has been determined, confirming a high degree of paradox whatever the considered single pairs. Last, we have verified that the value of the variance of the difference between twin images is always below the quantum (poissonian) limit, in order to ensure the particle character of the demonstration. Our demonstration shows that a single image pattern can reveal the quantum and non-local behavior of light.

  11. A paradox for traffic dynamics in complex networks with ATIS

    International Nuclear Information System (INIS)

    Zheng Jianfeng; Gao Ziyou

    2008-01-01

    In this work, we study the statistical properties of traffic (e.g., vehicles) dynamics in complex networks, by introducing advanced transportation information systems (ATIS). The ATIS can provide the information of traffic flow pattern throughout the network and have an obvious effect on path routing strategy for such vehicles equipped with ATIS. The ATIS can be described by the understanding of link cost functions. Different indices such as efficiency and system total cost are discussed in depth. It is found that, for random networks (scale-free networks), the efficiency is effectively improved (decreased) if ATIS is properly equipped; however the system total cost is largely increased (decreased). It indicates that there exists a paradox between the efficiency and system total cost in complex networks. Furthermore, we report the simulation results by considering different kinds of link cost functions, and the paradox is recovered. Finally, we extend our traffic model, and also find the existence of the paradox

  12. Bernstein's paradox of entangled quantum states

    International Nuclear Information System (INIS)

    Belinsky, A V; Chirkin, A S

    2013-01-01

    Bernstein's classical paradox of a regular colored-faced tetrahedron, while designed to illustrate the subtleties of probability theory, is strongly flawed in being asymmetric. Faces of tetrahedron are nonequivalent: three of them are single-colored, and one is many-colored. Therefore, even prior to formal calculations, a strong suspicion as to the independence of the color resulting statistics arises. Not so with entangled quantum states. In the schematic solutions proposed, while photon detection channels are completely symmetric and equivalent, the events that occur in them turn out to be statistically dependent, making the Bernstein paradox even more impressive due to the unusual behavior of quantum particles not obeying classical laws. As an illustrative example of the probability paradox, Greenberger–Horne–Zeilinger multiqubit states are considered. (methodological notes)

  13. Paradoxes in virtual team knowledge communication and trust building

    DEFF Research Database (Denmark)

    Petersen, Nils Braad

    2012-01-01

    This thesis proposal presents paradoxes within current trust and knowledge management literatures as a lens for understanding challenges in virtual teams working across organisational and geographic boundaries. By exposing contradictions within current virtual team research, the author proposes...... a need for a different, multi-level, multi-theoretical approach to virtual team research in order to overcome the paradoxes. A moderate constructionist research position building on Critical Realism is proposed. To situate the project within current literatures, trust, knowledge management and virtual...... team literatures are reviewed. These are used to support the paradoxes used as a lens for understanding. A research design is presented building on interviews, documentary analysis and observations analysed using Social Network Analysis and James Gee’s framework for discourse analysis. Finally...

  14. Traversing boundaries: thrombus in transit with paradoxical embolism

    Directory of Open Access Journals (Sweden)

    Varun Miriyala

    2016-09-01

    Full Text Available A 72-year-old male is diagnosed with paradoxical embolus after he presented with concurrent deep vein thrombosis, stroke, and multiple arterial emboli in the presence of a patent foramen ovale (PFO. Paradoxical embolus requires the passage of a thrombus from the venous into the arterial circulation through a right-to-left shunt leading to systemic embolism. But, despite the high incidence of PFO (27.3% across all age groups by autopsy, paradoxical embolism (PDE is uncommon, representing <2% of all arterial emboli. We present a case report where a thrombus has been directly observed passing through the PFO during an echocardiogram study; thus, clearly delineating the true cause of multiple thromboemboli and stoke in our patient. Subsequent Transesophageal Echocardiography (TEE also interestingly showed the thrombus in transit in the aorta and pulmonary artery.

  15. The Colombian Left: A Paradoxical Past; A Promising Future?

    Directory of Open Access Journals (Sweden)

    Charles Bergquist

    2017-07-01

    Full Text Available The essay explores the paradoxical history of the left in Colombia: how and why one of the weakest lefts in Latin America brought about the strongest and most lasting Marxist insurrection in the hemisphere in the decades following the Cuban Revolution. The article argues that the terms of this paradox are related, that the historic weakness of the left partly explains the force and longevity of revolutionary guerrillas, and that said paradox helps clarify not only the failure of several attempts to achieve a negotiated settlement of the armed conflict, but also the negative vote in the October 2016 plebiscite. Finally, it envisions a more promising future for the country’s left, provided that a lasting peace is consolidated.

  16. Difficulties in Genetics Problem Solving.

    Science.gov (United States)

    Tolman, Richard R.

    1982-01-01

    Examined problem-solving strategies of 30 high school students as they solved genetics problems. Proposes a new sequence of teaching genetics based on results: meiosis, sex chromosomes, sex determination, sex-linked traits, monohybrid and dihybrid crosses (humans), codominance (humans), and Mendel's pea experiments. (JN)

  17. Problem Solving, Scaffolding and Learning

    Science.gov (United States)

    Lin, Shih-Yin

    2012-01-01

    Helping students to construct robust understanding of physics concepts and develop good solving skills is a central goal in many physics classrooms. This thesis examine students' problem solving abilities from different perspectives and explores strategies to scaffold students' learning. In studies involving analogical problem solving…

  18. Problem Solving on a Monorail.

    Science.gov (United States)

    Barrow, Lloyd H.; And Others

    1994-01-01

    This activity was created to address a lack of problem-solving activities for elementary children. A "monorail" activity from the Evening Science Program for K-3 Students and Parents program is presented to illustrate the problem-solving format. Designed for performance at stations by groups of two students. (LZ)

  19. Solving complex fisheries management problems

    DEFF Research Database (Denmark)

    Petter Johnsen, Jahn; Eliasen, Søren Qvist

    2011-01-01

    A crucial issue for the new EU common fisheries policy is how to solve the discard problem. Through a study of the institutional set up and the arrangements for solving the discard problem in Denmark, the Faroe Islands, Iceland and Norway, the article identifies the discard problem as related...

  20. The Obesity Paradox: A Misleading Term That Should Be Abandoned.

    Science.gov (United States)

    Flegal, Katherine M; Ioannidis, John P A

    2018-04-01

    The term "obesity paradox" is a figure of speech, not a scientific term. The term has no precise definition and has been used to describe numerous observations that have little in common other than the finding of an association of obesity with a favorable outcome. The terminology has led to misunderstandings among researchers and the public alike. It's time for authors and editors to abandon the use of this term. Simply labeling counterintuitive findings as the "obesity paradox" adds no value. Unexpected findings should not be viewed negatively; such findings can lead to new knowledge, better treatments, and scientific advances. © 2018 The Obesity Society.

  1. The dissolver paradox as a coupled fast-thermal reactor

    International Nuclear Information System (INIS)

    Lutz, H.F.; Webb, P.S.

    1993-05-01

    The dissolver paradox is treated as coupled fast-thermal reactors. Each reactor is sub-critical but the coupling is sufficient to form a critical system. The practical importance of the system occurs when the fast system by itself is mass limited and the thermal system by itself is volume limited. Numerous 1D calculations have been made to calculate the neutron multiplication parameters of the separate fast and thermal systems that occur in the dissolver paradox. A model has been developed to describe the coupling between the systems. Monte Carlo calculations using the MCNP code have tested the model

  2. R and D Policies, Carbon Tax and Green Paradox

    International Nuclear Information System (INIS)

    Bermudez Neubauer, Mauricio; Grimaud, Andre; Rouge, Luc

    2016-01-01

    We study an economy in which a final good is produced by two sectors. One uses a non-renewable and polluting resource, the other a renewable and clean resource. A specific type of research is associated with each sector. The public authorities levy a carbon tax and simultaneously subsidise both research sectors. We study the impact of such a policy scheme on the rate of resource extraction and emissions. In the clean sector, the research subsidy and the carbon tax have opposite effects. If the tax creates a green paradox, the subsidy moderates it; if the tax slows resource extraction, then the subsidy generates a green paradox

  3. Resolving the Innovation Diffusion Paradox in Mobile App Stores

    DEFF Research Database (Denmark)

    Xiong, Bingqing; Tan, Chee-Wee; Wang, Weiquan

    2017-01-01

    to the abundance of apps and multitudinous promotional information. To this end, this study proposes branding as a strategy to tackle the innovation diffusion paradox. Specifically, we construct a research model that posits consumers’ brand awareness as an antecedent affecting their brand association and quality......The growing number of apps released on a daily basis has contributed to an innovation diffusion paradox whereby the frequency and intensity by which innovations are crowdsourced are stymieing their own diffusion. In mobile app stores, consumers are often constrained in their selection due...

  4. Testing the Transivity Explanation of the Allais Paradox

    DEFF Research Database (Denmark)

    Groes, Ebbe; Jacobsen, Hans Jørgen; Sloth, Birgitte

    1999-01-01

    This paper uses a two-dimensional version of a standard common consequence experiment to test the intransitivity explanation of Allais-paradox-type violations of expected utility theory. We compare the common consequence effect of two choice problems differing only with respect to whether...... intransitivity as an explanation of the Allais Paradox. The question whether violations of expected utility are mainly due to intransitivity or to violation of independence is important since it is exactly on this issue the main new decision theories differ...

  5. Solar Energy.

    Science.gov (United States)

    Eaton, William W.

    Presented is the utilization of solar radiation as an energy resource principally for the production of electricity. Included are discussions of solar thermal conversion, photovoltic conversion, wind energy, and energy from ocean temperature differences. Future solar energy plans, the role of solar energy in plant and fossil fuel production, and…

  6. Solar energy

    Science.gov (United States)

    Rapp, D.

    1981-01-01

    The book opens with a review of the patterns of energy use and resources in the United States, and an exploration of the potential of solar energy to supply some of this energy in the future. This is followed by background material on solar geometry, solar intensities, flat plate collectors, and economics. Detailed attention is then given to a variety of solar units and systems, including domestic hot water systems, space heating systems, solar-assisted heat pumps, intermediate temperature collectors, space heating/cooling systems, concentrating collectors for high temperatures, storage systems, and solar total energy systems. Finally, rights to solar access are discussed.

  7. Solar Combisystems

    DEFF Research Database (Denmark)

    Thür, Alexander

    2006-01-01

    This note first introduces what is a solar combisystem, the structure how a solar combisystem is build up and what are criteria’s to evaluate a solar combisystem concept. Further on the main components of a solar combisystem, the main characteristics and possible advantages and disadvantages...... compared to each other are described. It is not the goal of this note to explain the technical details how to design all components of a solar combisystem. This is done during other lectures of the solar course and in other basic courses as well. This note tries to explain how a solar combisystem...

  8. Solar Systems

    Science.gov (United States)

    1979-01-01

    The solar collectors shown are elements of domestic solar hot water systems produced by Solar One Ltd., Virginia Beach, Virginia. Design of these systems benefited from technical expertise provided Solar One by NASA's Langley Research Center. The company obtained a NASA technical support package describing the d e sign and operation of solar heating equipment in NASA's Tech House, a demonstration project in which aerospace and commercial building technology are combined in an energy- efficient home. Solar One received further assistance through personal contact with Langley solar experts. The company reports that the technical information provided by NASA influenced Solar One's panel design, its selection of a long-life panel coating which increases solar collection efficiency, and the method adopted for protecting solar collectors from freezing conditions.

  9. Solar radiophysics

    International Nuclear Information System (INIS)

    McLean, D.J.; Labrum, N.R.

    1985-01-01

    This book treats all aspects of solar radioastronomy at metre wavelengths, particularly work carried out on the Australian radioheliograph at Culgoora, with which most of the authors have been associated in one way or another. After an introductory section on historical aspects, the solar atmosphere, solar flares, and coronal radio emission, the book deals with instrumentation, theory, and details of observations and interpretations of the various aspects of metrewave solar radioastronomy, including burst types, solar storms, and the quiet sun. (U.K.)

  10. Separating models, ideas, and data to avoid a paradox : Rejoinder to Humphry

    NARCIS (Netherlands)

    Sijtsma, K.; Emons, W.H.M.

    2013-01-01

    This article is a rejoinder to Humphry’s (2013) comment on Sijtsma (2012). Sijtsma argued that the Rasch paradox does not exist but Humphry replies that the Rasch paradox can occur provided the measurement procedure is precise enough. The rejoinder argues that the debates about the Rasch paradox

  11. Design and construction of a solar energy tracking device | Ndinechi ...

    African Journals Online (AJOL)

    A solar tracking device using PIC16F873 microcontroller was developed to solve the problem of adjustment of solar panels for optimum solar reception. MPLAB software was used to develop sets of instructions in an assembly language. The choice of PIC16F873 microcontroller stemmed from its flexibility in producing a ...

  12. Globalization and Religion in Historical Perspective: A Paradoxical Relationship

    Directory of Open Access Journals (Sweden)

    Luke M. Herrington

    2013-03-01

    Full Text Available Religion has long been a driving force in the process of globalization. This idea is not controversial or novel thinking, nor is it meant to be. However, the dominant reasoning on the subject of globalization, expressed by authors like Thomas Friedman, places economics at the center of analysis, skewing focus from the ideational factors at work in this process. By expanding the definition of globalization to accommodate ideational factors and cultural exchange, religion’s agency in the process can be enabled. Interestingly, the story of religion and globalization is in some ways the history of globalization, but it is riddled with paradoxes, including the agent-opponent paradox, the subject of this article. Religion and globalization have a co-constitutive relationship, but religious actors are both agents of globalization and principals in its backlash. While some actors might benefit from a mutually reinforcing relationship with globalization, others are marginalized in some way or another, so it is necessary to expose the links and wedges that allow for such a paradox. To that end, the concepts of globalization and religious actors must be defined, and the history of the agent-opponent paradox, from the Buddhists of the Silk Road to the Jubilee campaign of 2000, must be elucidated.

  13. Design principles of paradoxical signaling in the immune system

    Science.gov (United States)

    Hart, Yuval

    A widespread feature of cell-cell signaling systems is paradoxical pleiotropy: the same secreted signaling molecule can induce opposite effects in the responding cells. For example, the cytokine IL-2 can promote proliferation and death of T-cells. The role of such paradoxical signaling remains unclear. We suggest that this mechanism provides homeostatic concentration of cells, independent of initial conditions. The crux of the paradoxical mechanism is the combination of a positive and a negative feedback loops creating two stable states - an OFF state and an ON state. Experimentally, we found that CD4 + cells grown in culture with a 30-fold difference in initial concentrations reached a homeostatic concentration nearly independent of initial cell levels (ON-state). Below an initial threshold, cell density decayed to extinction (OFF-state). Mathematical modeling explained the observed cell and cytokine dynamics and predicted conditions that shifted cell fate from homeostasis to the OFF-state. We suggest that paradoxical signaling provides cell circuits with specific dynamical features that are robust to environmental perturbations.

  14. The paradoxical path towards the memorable guest experience

    DEFF Research Database (Denmark)

    d'Ambrosio, Luigi; Madsen, Jan Halberg

    This paper examines the design of hospitality and tourism experiences staged for international tourists in the emerging Italian destination Campi Flegrei on the Bay of Naples. In particular, this case focuses on the paradox that Campi Flegrei (CF) hospitality providers around the Lake Avernus face...... in the conceptualisation of the guest experience in the context of a non-DMO governed destination....

  15. Which matrices are immune against the transportation paradox

    NARCIS (Netherlands)

    Deineko, Vladimir G.; Klinz, Bettina; Woeginger, Gerhard

    2003-01-01

    We characterize the m×n cost matrices of the transportation problem for which there exist supplies and demands such that the transportation paradox arises. Our characterization is fairly simple and can be verified within O(mn) computational steps. Moreover, we discuss the corresponding question for

  16. Underlying Paradox in the European Union's Multilingualism Policies

    Science.gov (United States)

    Johnson, Fern L.

    2013-01-01

    The European Union (EU) has developed comprehensive policies in recent years to promote multilingualism. In this article, major EU policy statements on multilingualism are analyzed to demonstrate how their underlying language ideology produces paradox by both encouraging multilingualism and regulating its definition within the EU. The first…

  17. Managing Coopetition in Supplier Networks : A Paradox Perspective

    NARCIS (Netherlands)

    Wilhelm, Miriam; Sydow, Jörg

    2018-01-01

    Scholars in the field of supply chain management have started to embrace the idea of simultaneous cooperation and competition (“coopetition”) in supplier networks but have mainly looked at coopetition from a structural perspective. In this paper, we complement the structural view with a paradox

  18. The mean, the median, and the St. Petersburg paradox.

    Science.gov (United States)

    Hayden, Benjamin Y; Platt, Michael L

    2009-06-01

    The St. Petersburg Paradox is a famous economic and philosophical puzzle that has generated numerous conflicting explanations. To shed empirical light on this phenomenon, we examined subjects' bids for one St. Petersburg gamble with a real monetary payment. We found that bids were typically lower than twice the smallest payoff, and thus much lower than is generally supposed. We also examined bids offered for several hypothetical variants of the St. Petersburg Paradox. We found that bids were weakly affected by truncating the gamble, were strongly affected by repeats of the gamble, and depended linearly on the initial "seed" value of the gamble. One explanation, which we call the median heuristic , strongly predicts these data. Subjects following this strategy evaluate a gamble as if they were taking the median rather than the mean of the payoff distribution. Finally, we argue that the distribution of outcomes embodied in the St. Petersburg paradox is so divergent from the Gaussian form that the statistical mean is a poor estimator of expected value, so that the expected value of the St. Petersburg gamble is undefined. These results suggest that this classic paradox has a straightforward explanation rooted in the use of a statistical heuristic.

  19. Climate policy and nonrenewable resources : The green paradox and beyond

    NARCIS (Netherlands)

    Pittel, Karen; van der Ploeg, Rick; Withagen, Cees

    2014-01-01

    Recent developments suggest that well-intended climate policies–including carbon taxes and subsidies for renewable energy – might not accomplish what policy makers intend. Hans-Werner Sinn has described a "green paradox," arguing that these policies could hasten global warming by encouraging owners

  20. TilE PARADOX OF PEDAGOGY TRANSPOSITION: Learning From ...

    African Journals Online (AJOL)

    A belief that a pedagogy developed and proven in one context may generalize or exist comfortably in other ... the new context. Further, paradox can be observed in the facilitation process ... the use of theory and pedagogy that have ... perspectives of educational change. While ..... communication and education systems -.

  1. Paradoxical implications of personal social media use for work

    NARCIS (Netherlands)

    van Zoonen, W.; Rice, R.E.

    2017-01-01

    New information and communication technologies can have paradoxical implications: they may be liberating and constraining at the same time. This field study examines the direct implications of personal social media use for work on employees’ autonomy and work pressure, and the indirect effects on

  2. Working-life - A paradox in Knowledge-Intensive Companies

    DEFF Research Database (Denmark)

    Ipsen, Christine

    2004-01-01

    A Working-Life Paradox in Knowledge Intensive Companies Keywords: Knowledge work, knowledge management, working-life, consulting companies. The purpose of this article is to identify the influence knowledge-work has on working life of the personnel in knowledge-intensive companies, more precisely...

  3. A Paradoxical Academic Identity: Fate, Utopia and Critical Hope

    Science.gov (United States)

    Sutton, Paul

    2015-01-01

    Using a dialectical mode of exposition, I offer a reflexive sociological theorisation of the paradox that characterises my academic identity: a fatalistic disenchantment concerning the colonisation of Higher Education (HE) by neoliberalism co-exists with a utopianism concerning HE's emancipatory possibilities. I begin with a discussion of Weber's…

  4. Time symmetry and interpretation of quantum mechanics. [Paradoxes

    Energy Technology Data Exchange (ETDEWEB)

    de Beauregard, O.C.

    1976-10-01

    A drastic resolution of the quantum paradoxes is proposed, combining (I) von Neumann's postulate that collapse of the state vector is due to the act of observation, and (II) my reinterpretation of von Neumann's quantal irreversibility as an equivalence between wave retardation and entropy increase, both being ''factlike'' rather than ''lawlike'' (Mehlberg). This entails a coupling of the two de jure symmetries between (I) retarded and (II) advanced waves, and between Aristotle's information as (I) learning and (II) willing awareness. Symmetric acceptance of cognizance as a source of retarded waves, and of will as a sink of advanced waves, is submitted as a central ''paradox'' of the Copernican or Einsteinian sort, out of which new light is shed upon previously known paradoxes, such as the EPR paradox, Schroedinger's cat, and Wigner's friend. Parapsychology is thus found to creep into the picture.

  5. Service Recovery Paradox In Indian Banking Industry: An Empirical Investigation

    Directory of Open Access Journals (Sweden)

    Arunesh Garg

    2013-10-01

    Full Text Available The present study examines existence of service recovery paradox in Indian banking industry. The study is taken up in the tri-city of Chandigarh, Panchkula and Mohali. The respondents are catego- rized into failure and no-failure groups on the basis of their service experience. Failure group consti- tutes those respondents who have experienced service recovery, and has been further divided into five sub-groups ranging from service recovery++ (service recovery better than expected to service recovery- - (service recovery worse than expected. Service recovery paradox is examined by com- paring service recovery++ group with no-failure group. The study shows evidence for existence of service recovery paradox in relation to satisfaction. It has been concluded that for service recovery paradox to exist, recovery effort has to be exceptionally good and much better than expectation level of the customer. The study suggests that service managers should take service failure as an opportunity to appease customers by providing a much better than expected recovery experience. However, organizations should not plan to create service failure situations because if they falter on imparting the recovery, customer satisfaction may be influenced negatively.

  6. The Content-Provider Paradox: Universities in the Information Ecosystem.

    Science.gov (United States)

    Vaidhyanathan, Siva

    2002-01-01

    Asserts that universities' rush to abandon their role as "national parks" in the information ecosystem in favor of becoming profitable "content providers" has led to a paradox: to generate new knowledge, researchers and teachers need broad content freedom, but the role of content provider requires highly restrictive policies to…

  7. Inferences from the dark sky: Olbers' paradox revisited

    International Nuclear Information System (INIS)

    Arpino, Mauro; Scardigli, Fabio

    2003-01-01

    The classical formulation of 'Olbers' paradox' consists in looking for an explanation of the fact that the sky at night is dark. We use the experimental datum of the nocturnal darkness in order to put constraints on a Newtonian cosmological model. We infer then that the stellar system in such a model should have had an origin at a finite time in the past

  8. Confucius Institutes and China's Soft Power: Practices and Paradoxes

    Science.gov (United States)

    Lo, Joe Tin-yau; Pan, Suyan

    2016-01-01

    Since China's implementation of the Confucius Institute (CI) project in 2004, most academic works have been written on its objectives, nature, features, development, problems and challenges, especially in terms of soft power projection. Though some of them could unravel the tensions and paradoxes in the CI project, there is a paucity of in-depth…

  9. A Paradox of Newtonian Gravitation and Laplace's Solution

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 21; Issue 5. A Paradox of Newtonian Gravitation and Laplace's Solution. General Article Volume ... A physical phenomenonthat can justify Laplace's suggestion isalso mentioned briefly. This article also posesan interesting mathematical problem that can ...

  10. Reflections on a Feminist Psychology of Women: Paradoxes and Prospects.

    Science.gov (United States)

    Fine, Michelle

    1985-01-01

    Reports an analysis of the methods and conclusions of articles published in Psychology of Women Quarterly from 1978 through 1981. Three paradoxes emerge from feminist psychology's commitent to contextual validity: the presumption of "progressive progress"; the implications of internal causes for social conditions; and the advancement of…

  11. A paradox of rationality à la von Neumann-Morgenstern

    NARCIS (Netherlands)

    Ismail, M.S.

    2015-01-01

    We show that there are games and decision situations in which it is not possible for the decision maker to be rational a la von Neumann-Morgenstern in both situations simultaneously, which is the source of the paradox presented in this note. We provide an assumption which is the necessary and

  12. Strategic brand management: Archetypes for managing brands through paradoxes

    OpenAIRE

    Högström, Claes; Gustafsson, ,Anders; Tronvoll, Bård

    2015-01-01

    Although brands are acknowledged as significant assets in a firm's value creation and differentiation process, branding literature often describes opposing perspectives and contradictory demands. This article develops a framework of three strategic brand management archetypes that provide new insights into the complexity and often paradoxical ambiguity of branding. By combining an empirical qualitative study with extant brand management and relational exchange theory, the authors ...

  13. Merleau-Ponty on Human Motility and Libet's Paradox | Mooney ...

    African Journals Online (AJOL)

    and-antedating” hypothesis/paradox based on the results of an on-going series of experiments dating back to 1964 that measured the neural adequacy [brain wave activity] of “conscious sensory experience”. What is fascinating about the ...

  14. Cajetan of Thiene on the Logic of Paradox

    Czech Academy of Sciences Publication Activity Database

    Hanke, Miroslav

    2016-01-01

    Roč. 13, č. 1 (2016), s. 71-95 ISSN 1214-8407 R&D Projects: GA ČR GP13-08389P Institutional support: RVO:67985955 Keywords : Cajetan of Thiene * logical operators * semantic paradoxes * scholastic logic Subject RIV: AA - Philosophy ; Religion

  15. Seismicity of the Paradox Basin and the Colorado Plateau interior

    International Nuclear Information System (INIS)

    Wong, I.G.

    1984-04-01

    National Waste Terminal Storage Program site qualification criteria require that a nuclear waste repository be located so that ground motion associated with the maximum credible and maximum probable earthquakes or other earthquake-associated effects will not have an unacceptable adverse impact on system performance. To determine whether a potential repository site located in the Paradox salt formation in the Paradox Basin of southeastern Utah satisfies these criteria, seismological studies were undertaken by Woodward-Clyde Consultants (WCC) in March 1978. These studies included: (1) analysis of historical seismicity; (2) analysis of contemporary seismicity and tectonics of both the Paradox Basin and surrounding Colorado Plateau, including an extensive program of microearthquake monitoring; (3) evaluation of the Paradox Basin crustal structure; (4) evaluation of mining-induced seismicity; and (5) characterization of design-related earthquake-induced ground motions pertinent to a potential repository site through studies of attentation and subsurface ground motions. A detailed discussion of the results of the seismological studies performed through December 1980 is contained in WCC (1982). The purpose of this topical report is to update and summarize the studies on the local, regional, and mining-induced seismicity conducted through December 1982. The limitations of any interpretations are also discussed and additional information that remains to be acquired is identified. 56 references, 45 figures, 4 tables

  16. A classical model explaining the OPERA velocity paradox

    CERN Document Server

    Broda, Boguslaw

    2011-01-01

    In the context of the paradoxical results of the OPERA Collaboration, we have proposed a classical mechanics model yielding the statistically measured velocity of a beam higher than the velocity of the particles constituting the beam. Ingredients of our model necessary to obtain this curious result are a non-constant fraction function and the method of the maximum-likelihood estimation.

  17. Can Rose’s paradox be useful in crime prevention?

    DEFF Research Database (Denmark)

    Christoffersen, Mogens; Joshi, Heather

    2015-01-01

    Geoffrey Rose’s prevention paradox obtains when the majority of cases with an adverse outcome come from a population of low or moderate risk, and only a few from a minority ‘high risk’ group. Preventive treatment is then better targeted widely than on the ‘high risk’ minority. This study tests wh...

  18. Achievement Data in IEA Studies and Simpson's Paradox

    Science.gov (United States)

    Zuzovsky, Ruth; Steinberg, David M.; Libman, Zipi

    2011-01-01

    This paper is meant to highlight the occurrence of Simpson's Paradox when using aggregated data obtained from two IEA studies in Israel, while ignoring the effect of a powerful intervening variable in the local context--the ethnicity factor. It will demonstrate faulty conclusions regarding either the absence of relationships between a contextual…

  19. Simpson's Paradox in the Interpretation of "Leaky Pipeline" Data

    Science.gov (United States)

    Walton, Paul H.; Walton, Daniel J.

    2016-01-01

    The traditional "leaky pipeline" plots are widely used to inform gender equality policy and practice. Herein, we demonstrate how a statistical phenomenon known as Simpson's paradox can obscure trends in gender "leaky pipeline" plots. Our approach has been to use Excel spreadsheets to generate hypothetical "leaky…

  20. Semantic paradox. A comparative analysis of scholastic and analytic views

    Czech Academy of Sciences Publication Activity Database

    Hanke, Miroslav

    2014-01-01

    Roč. 91, č. 3 (2014), s. 367-386 ISSN 2168-9105 R&D Projects: GA ČR(CZ) GP13-08389P Institutional support: RVO:67985955 Keywords : semantic paradoxes * scholastic logic * groundlessness * circularity * semantic pathology * two-line puzzles Subject RIV: AA - Philosophy ; Religion

  1. Aggression; a Paradoxical pathology of the mind | Kitapondya | Dar ...

    African Journals Online (AJOL)

    Dar Es Salaam Medical Students' Journal. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 15, No 1 (2008) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register. Aggression; a Paradoxical pathology of the mind.

  2. The mean, the median, and the St. Petersburg paradox

    Directory of Open Access Journals (Sweden)

    Benjamin Y. Hayden

    2009-06-01

    Full Text Available The St.~Petersburg Paradox is a famous economic and philosophical puzzle that has generated numerous conflicting explanations. To shed empirical light on this phenomenon, we examined subjects' bids for one St.~Petersburg gamble with a real monetary payment. We found that bids were typically lower than twice the smallest payoff, and thus much lower than is generally supposed. We also examined bids offered for several hypothetical variants of the St.~Petersburg Paradox. We found that bids were weakly affected by truncating the gamble, were strongly affected by repeats of the gamble, and depended linearly on the initial ``seed'' value of the gamble. One explanation, which we call the extit{median} extit{heuristic}, strongly predicts these data. Subjects following this strategy evaluate a gamble as if they were taking the median rather than the mean of the payoff distribution. Finally, we argue that the distribution of outcomes embodied in the St.~Petersburg paradox is so divergent from the Gaussian form that the statistical mean is a poor estimator of expected value, so that the expected value of the St.~Petersburg gamble is undefined. These results suggest that this classic paradox has a straightforward explanation rooted in the use of a statistical heuristic.

  3. The green paradox of the economics of exhaustible resources

    International Nuclear Information System (INIS)

    Cairns, Robert D.

    2014-01-01

    The green paradox states that an increasing tax on emissions of carbon dioxide, consonant with the expected increase in their marginal damages, may induce oil producers to shift their production toward the present and thereby to exacerbate the problem of climatic change. The model is based on Hotelling models of resource use that do not take the natural and technical features of oil production into account. Natural features include the decline of production through time according to a decline curve. Technical features include the requirement to sink investment in productive capacity. A model of a profit-maximizing firm indicates that, if these features are taken into account, the prediction of the green paradox is unlikely. - Highlights: • The green paradox is a direct application of Hotelling′s rule from the economics of exhaustible resources. • Hotelling′s analysis was a profound contribution to economic thought but evidence for it is weak. • Hotelling-style analysis assumes incorrectly that production can be rearranged at will among time periods. • Technological and geological features of oil production make the prediction of the green paradox unlikely

  4. The Use of Paradoxes as an Instructional Strategy.

    Science.gov (United States)

    Rastovac, John J.; Slavsky, David B.

    1986-01-01

    Describes a study in which paradoxes about seasons, hemispheres, and altitude were used to teach concepts in climatology. The misconceptions commonly held about the earth-sun distance relationship were used as an instructional strategy with an experimental group, which outgained the control group on an achievement test. (TW)

  5. Chiral tunnelling and the Klein paradox in graphene

    NARCIS (Netherlands)

    Katsnelson, M.I.; Novoselov, K.S.; Geim, A.K.

    2006-01-01

    The so-called Klein paradox - unimpeded penetration of relativistic particles through high and wide potential barriers - is one of the most exotic and counterintuitive consequences of quantum electrodynamics. The phenomenon is discussed in many contexts in particle, nuclear and astro-physics but

  6. Paradox Basin site characterization report: preparation papers, Gibson Dome location

    International Nuclear Information System (INIS)

    1982-11-01

    This document contains Part C, Identification of Pertinent Issues, of the site characterization report. The site characterization report, preparation papers, includes a description of detailed field studies and efforts to collect data to resolve key geologic and environmental issues in the Gibson Dome location within the Paradox Basin Region of Utah

  7. Danburite in evaporites of the Paradox basin, Utah.

    Science.gov (United States)

    Raup, O.B.; Madsen, B.M.

    1986-01-01

    Danburite (CaB2Si2O8) has been found as nodules in Pennsylvanian age marine evaporites. The occurrence of danburite and its relation to the host rock in the Paradox basin evaporites indicates that it most likely formed by diagenetic reaction of boron-rich, high-salinity brines with constituents in the anhydrite host rock.-from Authors

  8. Problem Solving with General Semantics.

    Science.gov (United States)

    Hewson, David

    1996-01-01

    Discusses how to use general semantics formulations to improve problem solving at home or at work--methods come from the areas of artificial intelligence/computer science, engineering, operations research, and psychology. (PA)

  9. How to solve mathematical problems

    CERN Document Server

    Wickelgren, Wayne A

    1995-01-01

    Seven problem-solving techniques include inference, classification of action sequences, subgoals, contradiction, working backward, relations between problems, and mathematical representation. Also, problems from mathematics, science, and engineering with complete solutions.

  10. Interactive Problem-Solving Interventions

    African Journals Online (AJOL)

    Frew Demeke Alemu

    concerted efforts of unofficial actors to establish unofficial communication ... Frew Demeke Alemu (LLB, LLM in International Human Rights Law from Lund ..... 24 Tamra Pearson d'Estrée (2009), “Problem-Solving Approaches”, (in The SAGE ...

  11. Identification and Assessment of Paradoxical Ventricular Wall Motion Using ECG Gated Blood Pool Scan - Comparison of cine Loop , Phase Analysis and Paradox Image -

    International Nuclear Information System (INIS)

    Lee, Jae Tae; Kim, Gwang Weon; Lee, Kyu Bo; Chung, Byung Chun; Whang, Kee Suk; Chae, Sung Chul; Paek, Wee Hyun; Cheon, Jae Eun; Lee, Hyong Woo; Chung, Jin Hong

    1990-01-01

    Sixty-four patients with paradoxical ventricular wall motion noticed both in angiocardiography or 2-dimensional echocardiography were assessed by ECG gated blood pool scan (GBPS). Endless cine loop image, phase and amplitude images and paradox image obtained by visual inspection of each cardiac beat or Fourier transformation of acquired raw data were investigated to determine the incremental value of GBPS with these processing methods for identification of paradoxical ventricular wall motion. The results were as follows:1) Paradoxical wall motions were observed on interventricular septum in 34 cases, left ventricular free wall in 26 and right ventricular wall in 24. Underlying heart diseases were is chemic (23 cases) valvular(9), congenital heart disease (12), cardiomyopathy (5), pericardial effusion(5), post cardiac surgery(3), corpulmonale (2), endocarditis (l) and right ventricular tumor(l). 2) Left ventricular ejection fractions of patients with paradoxical left ventricular wall motion were significantly lower than those with paradoxical septal motion (p <0.005). 3) The sensitivity of each processing methods for detecting paradoxical wall motion was 76.9% by phase analysis, 74.6% by endless cine loop mapping and 68.4% by paradox image manipulation respectively. Paradoxial motions visualized only in phase, paradox or both images were appeared as hypokinesia or akinesia in cine loop image. 4) All events could be identified by at least one of above three processing methods, however only 34 cases (48.4%) showed the paradoxical motions in all of the three images. By these findings, we concluded that simultaneous inspection of all above three processing methods-endless cine loop, phase analysis and paradox image is necessary for accurate identification and assessment of paradoxical ventricular wall motion when performing GBPS.

  12. Identification and Assessment of Paradoxical Ventricular Wall Motion Using ECG Gated Blood Pool Scan - Comparison of cine Loop , Phase Analysis and Paradox Image -

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jae Tae; Kim, Gwang Weon; Lee, Kyu Bo; Chung, Byung Chun; Whang, Kee Suk; Chae, Sung Chul; Paek, Wee Hyun; Cheon, Jae Eun [Kyungpook National University School of Medicine, Daegu (Korea, Republic of); Lee, Hyong Woo; Chung, Jin Hong [Yeongnam National University College of Medicine, Daegu (Korea, Republic of)

    1990-07-15

    Sixty-four patients with paradoxical ventricular wall motion noticed both in angiocardiography or 2-dimensional echocardiography were assessed by ECG gated blood pool scan (GBPS). Endless cine loop image, phase and amplitude images and paradox image obtained by visual inspection of each cardiac beat or Fourier transformation of acquired raw data were investigated to determine the incremental value of GBPS with these processing methods for identification of paradoxical ventricular wall motion. The results were as follows:1) Paradoxical wall motions were observed on interventricular septum in 34 cases, left ventricular free wall in 26 and right ventricular wall in 24. Underlying heart diseases were is chemic (23 cases) valvular(9), congenital heart disease (12), cardiomyopathy (5), pericardial effusion(5), post cardiac surgery(3), corpulmonale (2), endocarditis (l) and right ventricular tumor(l). 2) Left ventricular ejection fractions of patients with paradoxical left ventricular wall motion were significantly lower than those with paradoxical septal motion (p <0.005). 3) The sensitivity of each processing methods for detecting paradoxical wall motion was 76.9% by phase analysis, 74.6% by endless cine loop mapping and 68.4% by paradox image manipulation respectively. Paradoxial motions visualized only in phase, paradox or both images were appeared as hypokinesia or akinesia in cine loop image. 4) All events could be identified by at least one of above three processing methods, however only 34 cases (48.4%) showed the paradoxical motions in all of the three images. By these findings, we concluded that simultaneous inspection of all above three processing methods-endless cine loop, phase analysis and paradox image is necessary for accurate identification and assessment of paradoxical ventricular wall motion when performing GBPS.

  13. BEWARE, PERSON-YEARS! EXPERIENCE OF SIMPSON PARADOX OBSERVATION IN EPIDEMIOLOGICAL RISK EXAMINATIONS

    Directory of Open Access Journals (Sweden)

    V.F. Obesnyuk

    2017-12-01

    Full Text Available It is shown, on the examples of concrete publications, that "person-years" category application in multi-factor health risks analysis can lead to false conclusions in the process of observation data grouping due to Simpson paradox influence when examinations are performed via demographic or epidemiological techniques. The paradox occurs when heterogeneous strata are being compared. "Person-years" category first appeared in the middle of the 17th century, long before first applications of mathematical tools in statistics and probability theory; it does not fully correspond to up-to-date requirements of epidemiological research. Risk theory should change 17–18 century paradigm as it focuses on conditional probability of unwanted events occurrence and not on a principle of comparing their intensities. It is particularly vital in case when we deal with determining possible damage to health caused by effects exerted by such factors and under such conditions when individual damage cannot be measured objectively but when it is possible to quantitatively determine regularities of changes in stochastic ability to survive for a large group of people or remote consequences occurrence for it. We prove it is necessary to create specialized mathematical tools and hybrid software able to solve a risks assessment task as an inverse one. Mathematical tools of large contingency tables could serve as prototypes of such tools; we can also use multi-factor logistical and Poisson regressions which are usually applied in countable events analysis. We should note that it is also necessary to eliminate a number of methodological drawbacks which are attributable to the said tools.

  14. Paradoxes in carcinogenesis: New opportunities for research directions

    Directory of Open Access Journals (Sweden)

    Kramer Barnett S

    2007-08-01

    Full Text Available Abstract Background The prevailing paradigm in cancer research is the somatic mutation theory that posits that cancer begins with a single mutation in a somatic cell followed by successive mutations. Much cancer research involves refining the somatic mutation theory with an ever increasing catalog of genetic changes. The problem is that such research may miss paradoxical aspects of carcinogenesis for which there is no likely explanation under the somatic mutation theory. These paradoxical aspects offer opportunities for new research directions that should not be ignored. Discussion Various paradoxes related to the somatic mutation theory of carcinogenesis are discussed: (1 the presence of large numbers of spatially distinct precancerous lesions at the onset of promotion, (2 the large number of genetic instabilities found in hyperplastic polyps not considered cancer, (3 spontaneous regression, (4 higher incidence of cancer in patients with xeroderma pigmentosa but not in patients with other comparable defects in DNA repair, (5 lower incidence of many cancers except leukemia and testicular cancer in patients with Down's syndrome, (6 cancer developing after normal tissue is transplanted to other parts of the body or next to stroma previously exposed to carcinogens, (7 the lack of tumors when epithelial cells exposed to a carcinogen were transplanted next to normal stroma, (8 the development of cancers when Millipore filters of various pore sizes were was inserted under the skin of rats, but only if the holes were sufficiently small. For the latter paradox, a microarray experiment is proposed to try to better understand the phenomena. Summary The famous physicist Niels Bohr said "How wonderful that we have met with a paradox. Now we have some hope of making progress." The same viewpoint should apply to cancer research. It is easy to ignore this piece of wisdom about the means to advance knowledge, but we do so at our peril.

  15. Paradoxical hypotension during dobutamine infusion for myocardial perfusion scintigraphy

    International Nuclear Information System (INIS)

    Erguen, E.L.; Caner, B.; Atalar, E.; Karanfil, A.; Tokgoezoglu, L.

    1998-01-01

    Dobutamine as a predominant beta-1 agonist increases heart rate and myocardial contractility and at sufficient high doses, it also increases systolic blood pressure. This study was undertaken to describe instances of paradoxical hypotension during dobutamine infusion for Tl-201 myocardial perfusion SPECT study and the relationship between scintigraphic findings and hypotension occurred during dobutamine infusion. Methods: In 201 consecutive patients unable to perform adequate exercise, dobutamine Tl-201 myocardial SPECT was performed. Dobutamine was infused starting from 10 μg/kg/min increasing to 40 μ/kg/min. Paradoxical hypotension was defined as a decrease in systolic blood pressure ≥ 20 mmHg compared with baseline study. Paradoxical hypotension was observed in 40 patients (Group A) out of 201 (19.9%) while no significant change in systolic blood pressure was detected in the remaining 161 patients (Group B). Mean maximum fall in systolic blood pressure was 39±18 mmHg (range: 20-90). In 33 of 40 patients (83%) with paradoxical hypotension, scintigraphy was normal compared to 131 (81%) of the remaining 161 patients. In patients of Group A, angiography, echocardiography and tilt table tests were performed in 13, 11 and 6 patients respectively. Nine of 13 angiographic evaluations (69%), 10 of 11 echocardiographic evaluations (91%), all of the tilt table tests were normal. Additionally, all of the patients of Group A were clinically followed up at least 6 months after the myocardial perfusion scintigraphy. None of the patients had a cardiac event except one patient during the follow-up period. Conclusion: Paradoxical hypotension during dobutamine infusion for myocardial scintigraphy is not an uncommon finding and up to 19.9% patients may develop such hypotension. To maximize test safety, precautions should be taken during dobutamine myocardial stress test, since remarkable decrease in systolic blood pressure may occur. Unlike hypotension occurring with exercise

  16. Insufficiencies in solving global environmental problems by specialized scientific expertise

    International Nuclear Information System (INIS)

    Hartwig, S.G.; Kra, R.S.

    1989-01-01

    The most paradoxical and urgent problem faces the world today. We find ourselves between the horns of a dilemma. One horn represents the accelerating demand for energy, and the other, the irreversible degradation of our natural environment. There are two directions that we can take to solve our growing global crisis. The first step is to encourage scientific specialists to think in broader terms. The second necessary approach is to make decision makers aware of the complexity of the situation as well as the dangers of tunnel vision that experts often fall into. Therefore, to find a long-term holistic solution, decision makers, be they government officials or academics, must be, themselves, solution oriented and capable of directing scientists along broadened problem-solving pathways. Up till now, scientists have been required to research environmental problems, discover causal associations and determine effects. Contemporary scientists, in the truest sense of the meaning, are no longer generalists but are specialists in their own fields with great depth and accuracy of knowledge. However, experts of high standing may have difficulty visualizing adjacent sciences, which causes them to lose sight of topics peripheral to their main field of interest. The consequence of this can be that solutions to a problem will be sought only within particular and specialized areas, but it is, unfortunately, a fact of life that environmental problems do not come neatly packaged in scientific disciplines: they happen in their entirety, with all their synergistic implications. 5 refs., 5 figs

  17. Beyond Gamification:From Problem-solving to Problem-making

    OpenAIRE

    Ruffino, Paolo

    2014-01-01

    The problem I would like to highlight in this contribution is that gamification has been thought about too much as a tool for problem solving, and not enough as a tool for problem making. The idea of gamification as a tool for problem making could be more useful – although maybe paradoxically. As long as a technique is presented as a method for the solution of problems it can too easily become an authoritative proposal, which takes one solution and vision as necessarily better than the others...

  18. Tangram solved? Prefrontal cortex activation analysis during geometric problem solving.

    Science.gov (United States)

    Ayaz, Hasan; Shewokis, Patricia A; Izzetoğlu, Meltem; Çakır, Murat P; Onaral, Banu

    2012-01-01

    Recent neuroimaging studies have implicated prefrontal and parietal cortices for mathematical problem solving. Mental arithmetic tasks have been used extensively to study neural correlates of mathematical reasoning. In the present study we used geometric problem sets (tangram tasks) that require executive planning and visuospatial reasoning without any linguistic representation interference. We used portable optical brain imaging (functional near infrared spectroscopy--fNIR) to monitor hemodynamic changes within anterior prefrontal cortex during tangram tasks. Twelve healthy subjects were asked to solve a series of computerized tangram puzzles and control tasks that required same geometric shape manipulation without problem solving. Total hemoglobin (HbT) concentration changes indicated a significant increase during tangram problem solving in the right hemisphere. Moreover, HbT changes during failed trials (when no solution found) were significantly higher compared to successful trials. These preliminary results suggest that fNIR can be used to assess cortical activation changes induced by geometric problem solving. Since fNIR is safe, wearable and can be used in ecologically valid environments such as classrooms, this neuroimaging tool may help to improve and optimize learning in educational settings.

  19. Paradoxes of evidence in Russian addiction medicine.

    Science.gov (United States)

    Mendelevich, V D; Zalmunin, K Yu

    2015-01-01

    ) in patients dependent on opioids revealed no evidence of effectiveness of this approach. It was concluded that the use of antipsychotics is justified only in the presence of co-morbid psychiatric problems in patients [7]. In a recent meta-analytic review on the use of atypical antipsychotics for off-label indications (off-label), there was a lack of data to support the effectiveness of their use in substance abuse [8, 9]. The effectiveness of anticonvulsants in the treatment of opioid dependence syndrome has not been proven.In connection with the above puzzling fact, for Russian standards of treatment (clinical guidelines) the level of credibility of the effectiveness of antipsychotics and antidepressants in treatment of substance abuse is assessed as A or B. This paradox raises the question of the methodology for determining the level of credibility of evidence. It should be noted that Russian recommendations for inclusion of certain drugs and therapies are based on sufficient consensus of experts rather than on the results of meta-analyses [2]. This fact casts doubt on credibility and validity of scientific recommendations. Thus, one may say that Russian addiction medicine is not based on evidence, which is, in our view, erroneous and may impair the quality of care.

  20. Hydrostatic paradox: experimental verification of pressure equilibrium

    Science.gov (United States)

    Kodejška, Č.; Ganci, S.; Říha, J.; Sedláčková, H.

    2017-11-01

    This work is focused on the experimental verification of the balance between the atmospheric pressure acting on the sheet of paper, which encloses the cylinder completely or partially filled with water from below, where the hydrostatic pressure of the water column acts against the atmospheric pressure. First of all this paper solves a theoretical analysis of the problem, which is based, firstly, on the equation for isothermal process and, secondly, on the equality of pressures inside and outside the cylinder. From the measured values the confirmation of the theoretical quadratic dependence of the air pressure inside the cylinder on the level of the liquid in the cylinder is obtained, the maximum change in the volume of air within the cylinder occurs for the height of the water column L of one half of the total height of the vessel H. The measurements were made for different diameters of the cylinder and with plates made of different materials located at the bottom of the cylinder to prevent liquid from flowing out of the cylinder. The measured values were subjected to statistical analysis, which demonstrated the validity of the zero hypothesis, i.e. that the measured values are not statistically significantly different from the theoretically calculated ones at the statistical significance level α  =  0.05.

  1. Solar energy

    International Nuclear Information System (INIS)

    Kruisheer, N.

    1992-01-01

    In five brief articles product information is given on solar energy applications with special attention to the Netherlands. After an introduction on solar energy availability in the Netherlands the developments in solar boiler techniques are dealt with. Solar water heaters have advantages for the environment, and government subsidies stimulate different uses of such water heaters. Also the developments of solar cells show good prospects, not only for developing countries, but also for the industrialized countries. In brief the developments in solar energy storage and the connection of solar equipment to the grid are discussed. Finally attention is paid to the applications of passive solar energy in the housing construction, the use of transparent thermal insulation and the developments of translucent materials. 18 figs., 18 ills

  2. Solar Imagery

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Collection includes a variety of solar photographic and illustrated datasets contributed by a number of national and private solar observatories located worldwide....

  3. Solar Features

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Collection includes a variety of solar feature datasets contributed by a number of national and private solar observatories located worldwide.

  4. Solar Indices

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Collection includes a variety of indices related to solar activity contributed by a number of national and private solar observatories located worldwide. This...

  5. Solar Luminosity on the Main Sequence, Standard Model and Variations

    Science.gov (United States)

    Ayukov, S. V.; Baturin, V. A.; Gorshkov, A. B.; Oreshina, A. V.

    2017-05-01

    Our Sun became Main Sequence star 4.6 Gyr ago according Standard Solar Model. At that time solar luminosity was 30% lower than current value. This conclusion is based on assumption that Sun is fueled by thermonuclear reactions. If Earth's albedo and emissivity in infrared are unchanged during Earth history, 2.3 Gyr ago oceans had to be frozen. This contradicts to geological data: there was liquid water 3.6-3.8 Gyr ago on Earth. This problem is known as Faint Young Sun Paradox. We analyze luminosity change in standard solar evolution theory. Increase of mean molecular weight in the central part of the Sun due to conversion of hydrogen to helium leads to gradual increase of luminosity with time on the Main Sequence. We also consider several exotic models: fully mixed Sun; drastic change of pp reaction rate; Sun consisting of hydrogen and helium only. Solar neutrino observations however exclude most non-standard solar models.

  6. On the Modern History of Passive Solar Architecture

    DEFF Research Database (Denmark)

    Marsh, Rob

    2017-01-01

    This article examines the paradox of passive solar architecture within the Nordic context of Denmark, Norway and Sweden. Regulative developments to reduce space heating demand since the 1970s oil crisis are explored, highlighting architectural responses and the rise in prom-inence of passive solar...... design. An empirical study of passive solar housing schemes docu-ments architectural strategy, energy savings and extensive problems with overheating. A theo-retical study examines how passive solar was seen as advantageous when viewed with the 1985-2005 space heating paradigm, but actually resulted...... of Nordic modernism meant that passive solar architecture became the de-facto visual, aesthetic and functional expression of environmental design at that time. The article concludes by explor-ing the implications of the environmental paradigm for the architectural profession. By positing the architectural...

  7. Solar Special

    International Nuclear Information System (INIS)

    Van Roekel, A.; Osborne, J.; Schroeter, S.; De Jong, R.; De Saint Jacob, Y.

    2009-01-01

    Solar power is growing much faster than most policymakers and analysts realise. As costs come down and feed-in tariffs go up across Europe, a number of countries have started in pursuit of market leader Germany. But in Germany criticism is growing of the multi-billion-euro support schemes that keep the solar industry booming. In this section of the magazine several articles are dedicated to developments in solar energy in Europe. The first article is an overview story on the strong growing global market for solar cells, mainly thanks to subsidy schemes. The second article is on the position of foreign companies in the solar market in Italy. Article number three is dedicated to the conditions for solar technology companies to establish themselves in the German state of Saxony. Also the fifth article deals with the development of solar cells in Saxony: scientists, plant manufacturers and module producers in Saxony are working on new technologies that can be used to produce solar electricity cost-effectively. The goal is to bring the price down to match that of conventionally generated electricity within the next few years. The sixth article deals with the the solar power market in Belgium, which may be overheated or 'oversubsidized'. Article seven is on France, which used to be a pioneer in solar technology, but now produces only a fraction of the solar output of market leader Germany. However, new attractive feed-in-tariffs are changing the solar landscape drastically

  8. Solar Indices - Solar Radio Flux

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Collection includes a variety of indices related to solar activity contributed by a number of national and private solar observatories located worldwide. This...

  9. Customer-centered problem solving.

    Science.gov (United States)

    Samelson, Q B

    1999-11-01

    If there is no single best way to attract new customers and retain current customers, there is surely an easy way to lose them: fail to solve the problems that arise in nearly every buyer-supplier relationship, or solve them in an unsatisfactory manner. Yet, all too frequently, companies do just that. Either we deny that a problem exists, we exert all our efforts to pin the blame elsewhere, or we "Band-Aid" the problem instead of fixing it, almost guaranteeing that we will face it again and again.

  10. Simon on Problem-Solving

    DEFF Research Database (Denmark)

    Foss, Kirsten; Foss, Nicolai Juul

    as a general approach to problem solving. We apply these Simonian ideas to organizational issues, specifically new organizational forms. Specifically, Simonian ideas allow us to develop a morphology of new organizational forms and to point to some design problems that characterize these forms.Keywords: Herbert...... Simon, problem-solving, new organizational forms. JEL Code: D23, D83......Two of Herbert Simon's best-known papers are "The Architecture of Complexity" and "The Structure of Ill-Structured Problems." We discuss the neglected links between these two papers, highlighting the role of decomposition in the context of problems on which constraints have been imposed...

  11. Interactive problem solving using LOGO

    CERN Document Server

    Boecker, Heinz-Dieter; Fischer, Gerhard

    2014-01-01

    This book is unique in that its stress is not on the mastery of a programming language, but on the importance and value of interactive problem solving. The authors focus on several specific interest worlds: mathematics, computer science, artificial intelligence, linguistics, and games; however, their approach can serve as a model that may be applied easily to other fields as well. Those who are interested in symbolic computing will find that Interactive Problem Solving Using LOGO provides a gentle introduction from which one may move on to other, more advanced computational frameworks or more

  12. Inference rule and problem solving

    Energy Technology Data Exchange (ETDEWEB)

    Goto, S

    1982-04-01

    Intelligent information processing signifies an opportunity of having man's intellectual activity executed on the computer, in which inference, in place of ordinary calculation, is used as the basic operational mechanism for such an information processing. Many inference rules are derived from syllogisms in formal logic. The problem of programming this inference function is referred to as a problem solving. Although logically inference and problem-solving are in close relation, the calculation ability of current computers is on a low level for inferring. For clarifying the relation between inference and computers, nonmonotonic logic has been considered. The paper deals with the above topics. 16 references.

  13. Coupled solar still, solar heater

    Energy Technology Data Exchange (ETDEWEB)

    Davison, R R; Harris, W B; Moor, D H; Delyannis, A; Delyannis, E [eds.

    1976-01-01

    Computer simulation of combinations of solar stills and solar heaters indicates the probable economic advantage of such an arrangement in many locations if the size of the heater is optimized relative to that of the still. Experience with various low cost solar heaters is discussed.

  14. Solar Sailing

    Science.gov (United States)

    Johnson, Les

    2009-01-01

    Solar sailing is a topic of growing technical and popular interest. Solar sail propulsion will make space exploration more affordable and offer access to destinations within (and beyond) the solar system that are currently beyond our technical reach. The lecture will describe solar sails, how they work, and what they will be used for in the exploration of space. It will include a discussion of current plans for solar sails and how advanced technology, such as nanotechnology, might enhance their performance. Much has been accomplished recently to make solar sail technology very close to becoming an engineering reality and it will soon be used by the world s space agencies in the exploration of the solar system and beyond. The first part of the lecture will summarize state-of-the-art space propulsion systems and technologies. Though these other technologies are the key to any deep space exploration by humans, robots, or both, solar-sail propulsion will make space exploration more affordable and offer access to distant and difficult destinations. The second part of the lecture will describe the fundamentals of space solar sail propulsion and will describe the near-, mid- and far-term missions that might use solar sails as a propulsion system. The third part of the lecture will describe solar sail technology and the construction of current and future sailcraft, including the work of both government and private space organizations.

  15. The EPR paradox, Bell's inequality, and the question of locality

    Science.gov (United States)

    Blaylock, Guy

    2010-01-01

    Most physicists agree that the Einstein-Podolsky-Rosen-Bell paradox exemplifies much of the strange behavior of quantum mechanics, but argument persists about what assumptions underlie the paradox. To clarify what the debate is about, we employ a simple and well-known thought experiment involving two correlated photons to help us focus on the logical assumptions needed to construct the EPR and Bell arguments. The view presented in this paper is that the minimal assumptions behind Bell's inequality are locality and counterfactual definiteness but not scientific realism, determinism, or hidden variables as are often suggested. We further examine the resulting constraints on physical theory with an illustration from the many-worlds interpretation of quantum mechanics—an interpretation that we argue is deterministic, local, and realist but that nonetheless violates the Bell inequality.

  16. The energy efficiency paradox revisited through a partial observability approach

    International Nuclear Information System (INIS)

    Kounetas, Kostas; Tsekouras, Kostas

    2008-01-01

    The present paper examines the energy efficiency paradox demonstrated in Greek manufacturing firms through a partial observability approach. The data set used has resulted from a survey carried out among 161 energy-saving technology firm adopters. Maximum likelihood estimates that arise from an incidental truncation model reveal that the adoption of the energy-saving technologies is indeed strongly correlated to the returns of assets that are required in order to undertake the corresponding investments. The source of the energy efficiency paradox lies within a wide range of factors. Policy schemes that aim to increase the adoption rate of energy-saving technologies within the field of manufacturing are significantly affected by differences in the size of firms. Finally, mixed policies seem to be more effective than policies that are only capital subsidy or regulation oriented

  17. Four nuclear paradoxes which affect Japanese public opinion

    International Nuclear Information System (INIS)

    Tanaka, Y.

    1985-01-01

    Four major paradoxes - sociological, political, economic and psychological - are described with respect to the contemporary use of nuclear energy, drawing attention to Japan. Sociologically nuclear energy is a paradox because it is an irreversible social process; politically because it discriminates between the 'have' and 'have not' countries, making rich countries richer and poor countries poorer (political power); economically because, despite strong opposition for various reasons, there are also strong economic incentives for localities and individuals (stronger opposition may bring about greater profit in the long run); psychologically, because its acceptance or rejection tends to depend on the emotional 'psycho-logic' which seems to operate in the psychological process of individuals. Public acceptance seems to be both an institutional and a psychological process; consequently a close examination of the cross-pressures, resulting from all the influences is needed, to achieve public acceptance. Finally, it seems important to take into consideration cultural uniqueness as well as cross-cultural similarities. (author)

  18. Can an Evolutionary Analysis Dissolve the Paradox of Horror?

    DEFF Research Database (Denmark)

    Kjeldgaard-Christiansen, Jens; Clasen, Mathias; Johnson, John

    The paradox of horror” is the problem of why so many people are motivated to experience the negative emotions induced by horror media. In this talk, we argue that an evolutionary analysis may dissolve the paradox of horror. From an evolutionary perspective, horror may be analyzed as a simulation...... technology that allows users to attain adaptive experience with perceived threat and negative emotion in a safe environment. The argument is supported by results from a comprehensive MTurk survey of American users of horror media (n=1,071). Results include findings on the personal details (e.g., sex......), supernatural beliefs (e.g., paranormal beliefs), personality traits (e.g., Big Five), horror genre preferences (e.g., supernatural versus natural horror), and horror-induced emotional responses of users of horror media. The strongest individual predictors of horror media enjoyment are sex (male preference...

  19. PPI, paradoxes and Plato: who's sailing the ship?

    Science.gov (United States)

    Ives, Jonathan; Damery, Sarah; Redwod, Sabi

    2013-03-01

    Over the last decade, patient and public involvement (PPI) has become a requisite in applied health research. Some funding bodies demand explicit evidence of PPI, while others have made a commitment to developing PPI in the projects they fund. Despite being commonplace, there remains a dearth of engagement with the ethical and theoretical underpinnings of PPI processes and practices. More specifically, while there is a small (but growing) body of literature examining the effectiveness and impact of PPI, there has been relatively little reflection on whether the concept/practice of PPI is internally coherent. Here, the authors unpick a 'paradox' within PPI, which highlights a tension between its moral and pragmatic motivations and its implementation. The authors argue that this 'professionalisation paradox' means we need to rethink the practice, and purpose, of PPI in research.

  20. Energy absorption in cold inhomogeneous plasmas - The Herlofson paradox.

    Science.gov (United States)

    Crawford, F. W.; Harker, K. J.

    1972-01-01

    Confirmation of Barston's (1964) conclusions regarding the underlying mechanism of the Herlofson paradox by examining in detail several analytically tractable cases of delta-function and sinusoidal excitation. The effects of collisions and nonzero electron temperature in determining the steady state fields and dissipation are considered. Energy absorption without dissipation in plasmas is shown to be analogous to that occurring after application of a signal to a network of lossless resonant circuits. This analogy is pursued and is extended to cover Landau damping in a warm homogeneous plasma in which the resonating elements are the electron streams making up the velocity distribution. Some of the practical consequences of resonant absorption are discussed, together with a number of paradoxical plasma phenomena which can also be elucidated by considering a superposition of normal modes rather than a single Fourier component.

  1. Obesity paradox in cancer: new insights provided by body composition.

    Science.gov (United States)

    Gonzalez, Maria Cristina; Pastore, Carla A; Orlandi, Silvana P; Heymsfield, Steven B

    2014-05-01

    Obesity, defined by body mass index (BMI), appears to have a paradoxical protective effect in several chronic diseases. We investigated the obesity paradox in cancer patients by using body composition. The study was an observational study of 175 cancer patients assessed before chemotherapy. Obesity was defined as BMI (in kg/m(2)) ≥30 or fat mass index (FMI; fat mass divided by the square of height) ≥5.2 (men) and ≥8.2 (women) measured by using a bioelectrical impedance analysis. Low muscle mass (sarcopenia) was defined as fat-free mass index (fat-free mass divided by the square of height) cancer patients only when obesity is defined by BMI. Patients with sarcopenic obesity had the poorest prognosis. Cancer patients with high mortality risk can be identified by a body-composition assessment.

  2. The great silence science and philosophy of Fermi's paradox

    CERN Document Server

    Cirkovic, Milan M

    2018-01-01

    The Great Silence explores the multifaceted problem named after the great Italian physicist Enrico Fermi and his legendary 1950 lunchtime question "Where is everybody?" In many respects, Fermi's paradox is the richest and the most challenging problem for the entire field of astrobiology and the Search for ExtraTerrestrial Intelligence (SETI) studies. This book shows how Fermi's paradox is intricately connected with many fields of learning, technology, arts, and even everyday life. It aims to establish the strongest possible version of the problem, to dispel many related confusions, obfuscations, and prejudices, as well as to offer a novel point of entry to the many solutions proposed in existing literature. Cirkovic argues that any evolutionary worldview cannot avoid resolving the Great Silence problem in one guise or another.

  3. Optimal experience among teachers: new insights into the work paradox.

    Science.gov (United States)

    Bassi, Marta; Delle Fave, Antonella

    2012-01-01

    Several studies highlighted that individuals perceive work as an opportunity for flow or optimal experience, but not as desirable and pleasant. This finding was defined as the work paradox. The present study addressed this issue among teachers from the perspective of self-determination theory, investigating work-related intrinsic and extrinsic motivation, as well as autonomous and controlled behavior regulation. In Study 1, 14 teachers were longitudinally monitored with Experience Sampling Method for one work week. In Study 2, 184 teachers were administered Flow Questionnaire and Work Preference Inventory, respectively investigating opportunities for optimal experience, and motivational orientations at work. Results showed that work-related optimal experiences were associated with both autonomous regulation and with controlled regulation. Moreover, teachers reported both intrinsic and extrinsic motivation at work, with a prevailing intrinsic orientation. Findings provide novel insights on the work paradox, and suggestions for teachers' well-being promotion.

  4. Inductive reasoning and judgment interference: experiments on Simpson's paradox.

    Science.gov (United States)

    Fiedler, Klaus; Walther, Eva; Freytag, Peter; Nickel, Stefanie

    2003-01-01

    In a series of experiments on inductive reasoning, participants assessed the relationship between gender, success, and a covariate in a situation akin to Simpson's paradox: Although women were less successful then men according to overall statistics, they actually fared better then men at either of two universities. Understanding trivariate relationships of this kind requires cognitive routines similar to analysis of covariance. Across the first five experiments, however, participants generalized the disadvantage of women at the aggregate level to judgments referring to the different levels of the covariate, even when motivation was high and appropriate mental models were activated. The remaining three experiments demonstrated that Simpson's paradox could be mastered when the salience of the covariate was increased and when the salience of gender was decreased by the inclusion of temporal cues that disambiguate the causal status of the covariate. Copyright 2003 Society for Personality and Social Psychology, Inc.

  5. Exploratory shaft facility preliminary designs - Paradox Basin. Technical report

    International Nuclear Information System (INIS)

    1983-09-01

    The purpose of the Preliminary Design Report, Paradox Basin, is to provide a description of the preliminary design for an Exploratory Shaft Facility in the Paradox Basin, Utah. This issue of the report describes the preliminary design for constructing the exploratory shaft using the Large Hole Drilling Method of construction and outlines the preliminary design and estimates of probable construction cost. The Preliminary Design Report is prepared to complement and summarize other documents that comprise the design at the preliminary stage of completion, December 1982. Other design documents include drawings, cost estimates and schedules. The preliminary design drawing package, which includes the construction schedule drawing, depicts the descriptions in this report. For reference, a list of the drawing titles and corresponding numbers is included in the Appendix. The report is divided into three principal sections: Design Basis, Facility Description, and Construction Cost Estimate. 30 references

  6. Managerial Challenges Within Networks - Emphasizing the Paradox of Network Participation

    DEFF Research Database (Denmark)

    Jakobsen, Morten

    2003-01-01

    Flexibility and access to numerous resources are essential benefits associated with network participation. An important aspect of managing the network participation of a company is to maintain a dynamic portfolio of partners, and thereby keep up the strategic opportunities for development. However......, maintaining the dynamics within a network seems to be a complex challenge. There is a risk that the network ends up in The Paradox of Network Participation. The desired renewal and flexibility are not utilised because the involved parties preserve the existing networks structure consisting of the same...... and thereby sort out the paradox of network participation. Trust and information are mechanisms employed to absorb uncertainty. The relationship between trust and the requirement for information depends on the maturity of the relationship. When trust becomes too important as uncertainty absorption mechanism...

  7. Managerial challenges within networks: emphasizing the paradox of network participation

    DEFF Research Database (Denmark)

    Jakobsen, Morten

    Flexibility and access to numerous resources are essential benefits associated with network participation. An important aspect of managing the network participation of a company is to maintain a dynamic portfolio of partners, and thereby keep up the strategic opportunities for development. However......, maintaining the dynamics within a network seems to be a complex challenge. There is a risk that the network ends up in The Paradox of Network Participation. The desired renewal and flexibility are not utilised because the involved parties preserve the existing networks structure consisting of the same...... and thereby sort out the paradox of network participation. Trust and information are mechanisms employed to absorb uncertainty. The relationship between trust and the requirement for information depends on the maturity of the relationship. When trust becomes too important as uncertainty absorption mechanism...

  8. Anomalous fermion number nonconservation: Paradoxes in the level crossing picture

    International Nuclear Information System (INIS)

    Burnier, Y.

    2006-01-01

    In theories with anomalous fermion number nonconservation, the level-crossing picture is considered a faithful representation of the fermionic quantum number variation. It represents each created fermion by an energy level that crosses the zero-energy line from below. If several fermions of various masses are created, the level-crossing picture contains several levels that cross the zero-energy line and cross each other. However, we know from quantum mechanics that the corresponding levels cannot cross if the different fermions are mixed via some interaction potential. The simultaneous application of these two requirements on the level behavior leads to paradoxes. For instance, a naive interpretation of the resulting level-crossing picture gives rise to charge nonconservation. In this paper, we resolve this paradox by a precise calculation of the transition probability, and discuss what are the implications for the electroweak theory. In particular, the nonperturbative transition probability is higher if top quarks are present in the initial state

  9. How river rocks round: resolving the shape-size paradox.

    Directory of Open Access Journals (Sweden)

    Gabor Domokos

    Full Text Available River-bed sediments display two universal downstream trends: fining, in which particle size decreases; and rounding, where pebble shapes evolve toward ellipsoids. Rounding is known to result from transport-induced abrasion; however many researchers argue that the contribution of abrasion to downstream fining is negligible. This presents a paradox: downstream shape change indicates substantial abrasion, while size change apparently rules it out. Here we use laboratory experiments and numerical modeling to show quantitatively that pebble abrasion is a curvature-driven flow problem. As a consequence, abrasion occurs in two well-separated phases: first, pebble edges rapidly round without any change in axis dimensions until the shape becomes entirely convex; and second, axis dimensions are then slowly reduced while the particle remains convex. Explicit study of pebble shape evolution helps resolve the shape-size paradox by reconciling discrepancies between laboratory and field studies, and enhances our ability to decipher the transport history of a river rock.

  10. Geologic appraisal of Paradox basin salt deposits for water emplacement

    Science.gov (United States)

    Hite, Robert J.; Lohman, Stanley William

    1973-01-01

    Thick salt deposits of Middle Pennsylvanian age are present in an area of 12,000 square miles in the Paradox basin of southeast Utah and southwest Colorado. The deposits are in the Paradox Member of the Hermosa Formation. The greatest thickness of this evaporite sequence is in a troughlike depression adjacent to the Uncompahgre uplift on the northeast side of the basin.The salt deposits consist of a cyclical sequence of thick halite units separated by thin units of black shale, dolomite, and anhydrite. Many halite units are several hundred feet thick and locally contain economically valuable potash deposits.Over much of the Paradox basin the salt deposits occur at depths of more than 5,000 feet. Only in a series of salt anticlines located along the northeastern side of the basin do the salt deposits rise to relatively shallow depths. The salt anticlines can be divided geographically and structurally into five major systems. Each system consists of a long undulating welt of thickened salt over which younger rocks are arched in anticlinal form. Locally there are areas along the axes of the anticlines where the Paradox Member was never covered by younger sediments. This allowed large-scale migration of Paradox strata toward and up through these holes in the sediment cover forming diapiric anticlines.The central or salt-bearing cores of the anticlines range in thickness from about 2,500 to 14,000 feet. Structure in the central core of the salt anticlines is the result of both regional-compression and flowage of the Paradox Member into the anticlines from adjacent synclines. Structure in the central cores of the salt anticlines ranges from relatively undeformed beds to complexly folded and faulted masses, in which stratigraphic continuity is undemonstrable.The presence of thick cap rock .over many of the salt anticlines is evidence of removal of large volumes of halite by groundwater. Available geologic and hydrologic information suggests that this is a relatively slow

  11. A Paradox of Newtonian Gravitation and Laplace's Solution

    Indian Academy of Sciences (India)

    IAS Admin

    Newton's theory of gravitation solved many prob- lems of celestial ... Newtons law of universal gravitation was amazingly suc- cessful in solving ... Following the perfect cosmological principle the universe ... for different values of α. F1 = ∫ 1.

  12. Energy cost of walking: solving the paradox of steady state in the presence of variable walking speed.

    Science.gov (United States)

    Plasschaert, Frank; Jones, Kim; Forward, Malcolm

    2009-02-01

    Measurement of the energy cost of walking in children with cerebral palsy is used for baseline and outcome assessment. However, such testing relies on the establishment of steady state that is deemed present when oxygen consumption is stable. This is often assumed when walking speed is constant but in practice, speed can and does vary naturally. Whilst constant speed is achievable on a treadmill, this is often impractical clinically, thus rendering an energy cost test to an element of subjectivity. This paper attempts to address this issue by presenting a new method for calculating energy cost of walking that automatically applies a mathematically defined threshold for steady state within a (non-treadmill) walking trial and then strips out all of the non-steady state events within that trial. The method is compared with a generic approach that does not remove non-steady state data but rather uses an average value over a complete walking trial as is often used in the clinical environment. Both methods were applied to the calculation of several energy cost of walking parameters of self-selected walking speed in a cohort of unimpaired subjects and children with cerebral palsy. The results revealed that both methods were strongly correlated for each parameter but showed systematic significant differences. It is suggested that these differences are introduced by the rejection of non-steady state data that would otherwise have incorrectly been incorporated into the calculation of the energy cost of walking indices during self-selected walking with its inherent speed variation.

  13. Effects of stress on health and aging: Two paradoxes

    OpenAIRE

    Aldwin, Carolyn M; Yancura, Loriena A.

    2010-01-01

    Although older adults are thought to experience more stress and to be more vulnerable to its adverse effects, they often report less stress than younger adults and sometimes show more resilience. Paradoxically, while stress sometimes has long-term positive effects on well-being, studies differ as to whether this increases or decreases with age. We conclude that older individuals have learned to appraise and cope differently with stress. This protects them in spite of their increased physiolog...

  14. Uranium guidebook for the Paradox Basin, Utah and Colorado

    International Nuclear Information System (INIS)

    Anon.

    1978-01-01

    Various data concerning uranium production and reserves of the Paradox Basin are compiled herein. Current production from 2 Utah mills and 1 Colorado mill is estimated at 5.4 million pounds of U 3 O 8 . An overview of uranium mining, geology, tectonics, and types of ore deposits is presented. Detailed description of the 11 mining districts and 21 mining areas are included. Detailed maps and exploration guides are included as assistance to evaluating and seeking new uranium deposits

  15. What Is Sexual Orientation All About? Explaining an Evolutionary Paradox

    OpenAIRE

    Brad Bowins

    2015-01-01

    Numerous psychological, biological, and evolutionary theories have been proposed to explain sexual orientation. For a theory to be valid it must account for the evolutionary or Darwinian paradox of how homosexual behavior seemingly blocking evolutionary fitness could have evolved. Typically it is only evolutionary based theories that attempt to address this issue. All theories proposed to date have limitations, a major one being that they tend to be specific for male or female sexual orientat...

  16. Paradoxes of Technology: Consumer Cognizance, Emotions, and Coping Strategies.

    OpenAIRE

    Mick, David Glen; Fournier, Susan

    1998-01-01

    Although technological products are unavoidable in contemporary life, studies focusing on them in the consumer behavior field have been few and narrow. In this article, we investigate consumers' perspectives, meanings, and experiences in relation to a range of technological products, emphasizing lengthy and repeated interviews with 29 households, including a set of first-time owners. We draw on literatures spanning from technology, paradox, and postmodernism to clinical and social psychology,...

  17. Strategic brand management: Archetypes for managing brandsthrough paradoxes

    OpenAIRE

    Högström, Claes; Gustafsson, Anders; Tronvoll, Bård

    2014-01-01

    This is the authors' accepted and refereed manuscript to the article Although brands are acknowledged as significant assets in a firm‟s value creation and differentiation process, branding literature often describes opposing perspectives and contradictory demands. This article develops a framework of three strategic brand management archetypes that provide new insights into the complexity and often paradoxical ambiguity of branding. By combining an empirical qualitative study w...

  18. Paradoxical affinities: otherness and ambivalence as creative pathways.

    Science.gov (United States)

    Wiener, Jan

    2018-06-01

    Referring to her own background as the child of Jewish refugees forced to leave their countries of origin before the second World War, the author describes how her attitude towards Jung and his ideas has evolved. The role of paradoxical affinities that have affected the author's life and identity as a Jungian analyst are considered, alongside the impact of experiences of otherness whilst supervising and teaching abroad, particularly in Eastern Europe. © 2018, The Society of Analytical Psychology.

  19. Cerebrovascular Accident Secondary to Paradoxical Embolism Following Arteriovenous Graft Thrombectomy

    OpenAIRE

    Santos, Jolina Pamela; Hamadeh, Zaher; Ansari, Naheed

    2012-01-01

    Thrombectomy is a common procedure performed to declot thrombosed dialysis arteriovenous fistula (AVF) or arteriovenous graft (AVG). Complications associated with access thrombectomy like pulmonary embolism have been reported, but paradoxical embolism is extremely rare. We report a case of a 74-year-old black man with past medical history significant for end-stage renal disease (ESRD), atrial fibrillation on anticoagulation with warfarin, who presented to our hospital with lethargy, aphasia, ...

  20. Tectonic isolation from regional sediment sourcing of the Paradox Basin

    Science.gov (United States)

    Smith, T. M.; Saylor, J.; Sundell, K. E.; Lapen, T. J.

    2017-12-01

    The Appalachian and Ouachita-Marathon mountain ranges were created by a series of tectonic collisions that occurred through the middle and late Paleozoic along North America's eastern and southern margins, respectively. Previous work employing detrital zircon U-Pb geochronology has demonstrated that fluvial and eolian systems transported Appalachian-derived sediment across the continent to North America's Paleozoic western margin. However, contemporaneous intraplate deformation of the Ancestral Rocky Mountains (ARM) compartmentalized much of the North American western interior and mid-continent. We employ lithofacies characterization, stratigraphic thickness, paleocurrent data, sandstone petrography, and detrital zircon U-Pb geochronology to evaluate source-sink relationships of the Paradox Basin, which is one of the most prominent ARM basins. Evaluation of provenance is conducted through quantitative comparison of detrital zircon U-Pb distributions from basin samples and potential sources via detrital zircon mixture modeling, and is augmented with sandstone petrography. Mixing model results provide a measure of individual source contributions to basin stratigraphy, and are combined with outcrop and subsurface data (e.g., stratigraphic thickness and facies distributions) to create tectonic isolation maps. These maps elucidate drainage networks and the degree to which local versus regional sources influence sediment character within a single basin, or multiple depocenters. Results show that despite the cross-continental ubiquity of Appalachian-derived sediment, fluvial and deltaic systems throughout much of the Paradox Basin do not record their influence. Instead, sediment sourcing from the Uncompahgre Uplift, which has been interpreted to drive tectonic subsidence and formation of the Paradox Basin, completely dominated its sedimentary record. Further, the strong degree of tectonic isolation experienced by the Paradox Basin appears to be an emerging, yet common

  1. Robust Quantitative Comparative Statics for a Multimarket Paradox

    OpenAIRE

    Tobias Harks; Philipp von Falkenhausen

    2013-01-01

    We introduce a quantitative approach to comparative statics that allows to bound the maximum effect of an exogenous parameter change on a system's equilibrium. The motivation for this approach is a well known paradox in multimarket Cournot competition, where a positive price shock on a monopoly market may actually reduce the monopolist's profit. We use our approach to quantify for the first time the worst case profit reduction for multimarket oligopolies exposed to arbitrary positive price sh...

  2. Human Problem Solving in 2012

    Science.gov (United States)

    Funke, Joachim

    2013-01-01

    This paper presents a bibliography of 263 references related to human problem solving, arranged by subject matter. The references were taken from PsycInfo and Academic Premier data-base. Journal papers, book chapters, and dissertations are included. The topics include human development, education, neuroscience, and research in applied settings. It…

  3. Solved problems in classical electromagnetism

    CERN Document Server

    Franklin, Jerrold

    2018-01-01

    This original Dover publication is the companion to a new edition of the author's Classical Electromagnetism: Second Edition. The latter volume will feature only basic answers; this book will contain some problems from the reissue as well as many other new ones. All feature complete, worked-out solutions and form a valuable source of problem-solving material for students.

  4. Error Patterns in Problem Solving.

    Science.gov (United States)

    Babbitt, Beatrice C.

    Although many common problem-solving errors within the realm of school mathematics have been previously identified, a compilation of such errors is not readily available within learning disabilities textbooks, mathematics education texts, or teacher's manuals for school mathematics texts. Using data on error frequencies drawn from both the Fourth…

  5. Quantitative Reasoning in Problem Solving

    Science.gov (United States)

    Ramful, Ajay; Ho, Siew Yin

    2015-01-01

    In this article, Ajay Ramful and Siew Yin Ho explain the meaning of quantitative reasoning, describing how it is used in the to solve mathematical problems. They also describe a diagrammatic approach to represent relationships among quantities and provide examples of problems and their solutions.

  6. Students' Problem Solving and Justification

    Science.gov (United States)

    Glass, Barbara; Maher, Carolyn A.

    2004-01-01

    This paper reports on methods of students' justifications of their solution to a problem in the area of combinatorics. From the analysis of the problem solving of 150 students in a variety of settings from high-school to graduate study, four major forms of reasoning evolved: (1) Justification by Cases, (2) Inductive Argument, (3) Elimination…

  7. Moderating attitudes in times of violence through paradoxical thinking intervention.

    Science.gov (United States)

    Hameiri, Boaz; Porat, Roni; Bar-Tal, Daniel; Halperin, Eran

    2016-10-25

    In the current paper, we report a large-scale randomized field experiment, conducted among Jewish Israelis during widespread violence. The study examines the effectiveness of a "real world," multichanneled paradoxical thinking intervention, with messages disseminated through various means of communication (i.e., online, billboards, flyers). Over the course of 6 wk, we targeted a small city in the center of Israel whose population is largely rightwing and religious. Based on the paradoxical thinking principles, the intervention involved transmission of messages that are extreme but congruent with the shared Israeli ethos of conflict. To examine the intervention's effectiveness, we conducted a large-scale field experiment (prepost design) in which we sampled participants from the city population (n = 215) and compared them to a control condition (from different places of residence) with similar demographic and political characteristics (n = 320). Importantly, participants were not aware that the intervention was related to the questionnaires they answered. Results showed that even in the midst of a cycle of ongoing violence within the context of one of the most intractable conflicts in the world, the intervention led hawkish participants to decrease their adherence to conflict-supporting attitudes across time. Furthermore, compared with the control condition, hawkish participants that were exposed to the paradoxical thinking intervention expressed less support for aggressive policies that the government should consider as a result of the escalation in violence and more support for conciliatory policies to end the violence and promote a long-lasting agreement.

  8. Authority as paradox: the transformations of Don Quijote.

    Science.gov (United States)

    Priel, Beatriz

    2006-12-01

    The author's contention is that the analysand's temporary attribution of authority to the analyst is inherent in the analytic situation; this is seen as a transitional and paradoxical form of authority pertaining neither to internal nor external reality, but dwelling in the analytic third. The author proposes a conceptualization of psychoanalytic authority as a form of aesthetic authority according to Gadamer's definitions. While the scientific and hermeneutic codes for the understanding of authority in psychoanalysis assume that the main issue at stake is the delimitation of the objectivity or the subjectivity of the analyst's knowledge, this aesthetic perspective centres on the analysand's attribution of a claim of truth to analytic interpretations, and on the experience of recognition. The experience of recognition of a possible truth is particular and context-bound, as well as self-transformational. A reading of three episodes from Cervantes's The history of Don Quixote de la Mancha illuminates the transitional and paradoxical character of aesthetic authority within a transformational dialogue. These episodes are read as dramatizations of different positions vis-à-vis the paradoxical authority that characterizes transformational dialogues.

  9. Patent Foramen Ovale: Is Stroke Due to Paradoxical Embolism?

    Science.gov (United States)

    Ranoux, D.; Cohen, A.; Cabanes, L.; Amarenco, P.; Bousser, M. G.; Mas, J. L.

    1993-01-01

    Background and Purpose: A patent foramen ovale has been reported to be significantly more frequent in young stroke patients than in matched control subjects, and paradoxical embolism has been suggested as the main mechanism of stroke in-this situation. The present study was designed to test this hypothesis. Methods: Sixty-eight consecutive patients under 55 years of age presenting with an ischemic stroke had an extensive workup, including transesophageal echocardiography with contrast. We compared the prevalence of criteria for the diagnosis of paradoxical embolism in patients with and without a patent foramen ovale. Results: A patent foramen ovale was found in 32 patients (47%). A Valsalva-provoking activity was present at stroke onset in six patients with a patent foramen ovale and in eight patients with no patent foramen ovale (X(sup 2)=0.1, nonsignificant). Clinical/radiological features suggestive of an embolic mechanism were not more frequent in patients with a patent foramen ovale. Clinical evidence of deep vein thrombosis was present in one patient with a patent foramen ovale and in none of the others. No occult venous thrombosis was found in a subgroup of patients with a patent foramen ovale and no definite cause for stroke who underwent venography (n=13). Conclusions. Our results do not support the hypothesis that paradoxical embolism is the primary mechanism of stroke in patients with a patent foramen ovale. (Stroke 1993;24:31-34) KEY WORDS e cerebral ischemia e embolism foramen ovale, patent

  10. Visualized Characterization for Cerebral Response of Acupuncture Deqi: Paradox Underway

    Directory of Open Access Journals (Sweden)

    Jie Yang

    2013-01-01

    Full Text Available Acupuncture as an oriental natural healing therapy with prolonged history has been extensively utilized in the management of great numbers of disorders. Deqi, a renowned acupuncture needling sensation, is profoundly regarded as the predictor and also the prerequisite of a preferable acupuncture treatment efficacy. Till now, there is still no consistency being reached towards the mechanism of acupuncture Deqi as a result of the discrepancy for publicly acknowledged evidence. Recent visualized research on Deqi using modern technologies has demonstrated possible central mechanism towards it. However, there is a conspicuous paradox underway in the research of cerebral response to acupuncture Deqi. This paper provided a view of up-to-date studies using visualized tools to characterize the brain response to acupuncture Deqi, such as functional magnetic resonance imaging (fMRI and positron emission tomography/computed tomography (PET/CT. The paradox was extruded to highlight certain reasons from a TCM view. It is hypothesized that acupoints located at different dermal sites, state of participant, and needling manipulation can all contribute to the current paradox. Hence, further studies on acupuncture Deqi should pay more attention to the strategy of experiment design with generalized measurement, valid sham control methods, and more to subjects in diseased condition.

  11. Paradoxical sphincter contraction is rarely indicative of anismus.

    Science.gov (United States)

    Voderholzer, W A; Neuhaus, D A; Klauser, A G; Tzavella, K; Müller-Lissner, S A; Schindlbeck, N E

    1997-08-01

    Anismus is thought to be a cause of chronic constipation by producing outlet obstruction. The underlying mechanism is paradoxical contraction of the anal sphincter or puborectalis muscle. However, paradoxical sphincter contraction (PSC) also occurs in healthy controls, so anismus may be diagnosed too often because it may be based on a non-specific finding related to untoward conditions during the anorectal examination. To investigate the pathophysiological importance of PSC found at anorectal manometry in constipated patients and in patients with stool incontinence. Digital rectal examination and anorectal manometry were performed in 102 chronically constipated patients, 102 patients with stool incontinence, and in 18 controls without anorectal disease. In 120 of the 222 subjects defaecography was also performed. Paradoxical sphincter contraction was defined as a sustained increase in sphincter pressure during straining. Anismus was assumed when PSC was present on anorectal manometry and digital rectal examination and the anorectal angle did not widen on defaecography. Manometric PSC occurred about twice as often in constipated patients as in incontinent patients (41.2% versus 25.5%, p anismus is rare.

  12. The diagnosis and treatment of paradoxical embolism: a systematic review

    Directory of Open Access Journals (Sweden)

    Atooshe Rohani

    2016-11-01

    Full Text Available One in five adults has patent foramen ovale (PFO, which is typically without symptoms. Because of the low pressure in both atria and the anatomical position of the septum secundum, there is no left-to-right shunting and little right-to-left shunting in the general condition; however, when the right atrial pressure increases, this slit-like flap separates and allows right-to-left shunting. According to the Johnson criteria, simultaneous occurrences of arterial emboli, such as those caused by cerebrovascular accident or pulmonary embolism, demonstrate the presence of paradoxical embolism through a PFO. When a patient presents with multivascular arterial embolism, the clinician should perform a contrast transthoracic echo, a transesophageal (TEE, a real-time three-dimensional TEE, and even an intracardiac echocardiography (ICE in order to differentiate between PFO, flat atrial septal defect (ASD and hybrid defects. The randomized trials that have assessed therapeutic interventions for paradoxical embolism have not produced any clear guidelines as to how best to treat this condition. The classic treatment is surgical embolectomy with exploration of the right chambers and the pulmonary arteries under full cardiopulmonary bypass. Patients with a history of ≥1 paradoxical embolism may be indicated for device PFO closure.

  13. Paradoxical response during antituberculous treatment for abdominal tuberculosis

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Ji Young; Kwon, Jung Hyeok; Kim, Mi Jeong; Chang, Hyuk Won; Hwang, Jae Seok; Cho, Kwang Bum; Park, Kyung Sik; Jang, Byoung Kuk; Chung, Woo Jin [Dongsan Medical Center, Keimyung University School of Medicine, Daegu (Korea, Republic of)

    2006-12-15

    The purpose of our study was to evaluate clinical and CT findings of paradoxical response during treatment for abdominal tuberculosis. Authors reviewed the patient records of 138 patients with abdominal tuberculosis during a recent 6-year period and we selected 11 patients with a paradoxical response. The CT findings and pathologic findings of the initial lesions and new lesions were reviewed. The intervals between initiation of therapy and the detection of new lesions, improvement of new lesion and the final follow-up were evaluated. At the initial presentation, we identified tuberculous peritonitis in 8 patients, tuberculous lymphadenitis in 3 patients and ileocolic tuberculosis in two patients. New lesions were identified at 2-10 months (mean: 3.8 months) after the initiation of therapy and following improvement of the initial lesions. The new lesions were perihepatic caseous abscess (n=4), hepatic tuberculoma (n=3), hepatic caseous abscess (n=1), tuberculous lymphadenitis (n=3), ileocolic tuberculosis (n=3), and splenic tuberculoma (n=1). Improvement of new lesions was noted at 4-14 months (mean: 7.6 months). At the final follow-up of seven patients, the new lesions disappeared and four patients still had small residual lesions. New lesions that develop in a patient with initial improvement should be considered a paradoxical response that will ultimately improve with continuation of the original medication.

  14. Paradoxical response during antituberculous treatment for abdominal tuberculosis

    International Nuclear Information System (INIS)

    Kim, Ji Young; Kwon, Jung Hyeok; Kim, Mi Jeong; Chang, Hyuk Won; Hwang, Jae Seok; Cho, Kwang Bum; Park, Kyung Sik; Jang, Byoung Kuk; Chung, Woo Jin

    2006-01-01

    The purpose of our study was to evaluate clinical and CT findings of paradoxical response during treatment for abdominal tuberculosis. Authors reviewed the patient records of 138 patients with abdominal tuberculosis during a recent 6-year period and we selected 11 patients with a paradoxical response. The CT findings and pathologic findings of the initial lesions and new lesions were reviewed. The intervals between initiation of therapy and the detection of new lesions, improvement of new lesion and the final follow-up were evaluated. At the initial presentation, we identified tuberculous peritonitis in 8 patients, tuberculous lymphadenitis in 3 patients and ileocolic tuberculosis in two patients. New lesions were identified at 2-10 months (mean: 3.8 months) after the initiation of therapy and following improvement of the initial lesions. The new lesions were perihepatic caseous abscess (n=4), hepatic tuberculoma (n=3), hepatic caseous abscess (n=1), tuberculous lymphadenitis (n=3), ileocolic tuberculosis (n=3), and splenic tuberculoma (n=1). Improvement of new lesions was noted at 4-14 months (mean: 7.6 months). At the final follow-up of seven patients, the new lesions disappeared and four patients still had small residual lesions. New lesions that develop in a patient with initial improvement should be considered a paradoxical response that will ultimately improve with continuation of the original medication

  15. Solving Differential Equations in R: Package deSolve

    Directory of Open Access Journals (Sweden)

    Karline Soetaert

    2010-02-01

    Full Text Available In this paper we present the R package deSolve to solve initial value problems (IVP written as ordinary differential equations (ODE, differential algebraic equations (DAE of index 0 or 1 and partial differential equations (PDE, the latter solved using the method of lines approach. The differential equations can be represented in R code or as compiled code. In the latter case, R is used as a tool to trigger the integration and post-process the results, which facilitates model development and application, whilst the compiled code significantly increases simulation speed. The methods implemented are efficient, robust, and well documented public-domain Fortran routines. They include four integrators from the ODEPACK package (LSODE, LSODES, LSODA, LSODAR, DVODE and DASPK2.0. In addition, a suite of Runge-Kutta integrators and special-purpose solvers to efficiently integrate 1-, 2- and 3-dimensional partial differential equations are available. The routines solve both stiff and non-stiff systems, and include many options, e.g., to deal in an efficient way with the sparsity of the Jacobian matrix, or finding the root of equations. In this article, our objectives are threefold: (1 to demonstrate the potential of using R for dynamic modeling, (2 to highlight typical uses of the different methods implemented and (3 to compare the performance of models specified in R code and in compiled code for a number of test cases. These comparisons demonstrate that, if the use of loops is avoided, R code can efficiently integrate problems comprising several thousands of state variables. Nevertheless, the same problem may be solved from 2 to more than 50 times faster by using compiled code compared to an implementation using only R code. Still, amongst the benefits of R are a more flexible and interactive implementation, better readability of the code, and access to R’s high-level procedures. deSolve is the successor of package odesolve which will be deprecated in

  16. Problem solving skills for schizophrenia.

    Science.gov (United States)

    Xia, J; Li, Chunbo

    2007-04-18

    The severe and long-lasting symptoms of schizophrenia are often the cause of severe disability. Environmental stress such as life events and the practical problems people face in their daily can worsen the symptoms of schizophrenia. Deficits in problem solving skills in people with schizophrenia affect their independent and interpersonal functioning and impair their quality of life. As a result, therapies such as problem solving therapy have been developed to improve problem solving skills for people with schizophrenia. To review the effectiveness of problem solving therapy compared with other comparable therapies or routine care for those with schizophrenia. We searched the Cochrane Schizophrenia Group's Register (September 2006), which is based on regular searches of BIOSIS, CENTRAL, CINAHL, EMBASE, MEDLINE and PsycINFO. We inspected references of all identified studies for further trials. We included all clinical randomised trials comparing problem solving therapy with other comparable therapies or routine care. We extracted data independently. For homogenous dichotomous data we calculated random effects, relative risk (RR), 95% confidence intervals (CI) and, where appropriate, numbers needed to treat (NNT) on an intention-to-treat basis. For continuous data, we calculated weighted mean differences (WMD) using a random effects statistical model. We included only three small trials (n=52) that evaluated problem solving versus routine care, coping skills training or non-specific interaction. Inadequate reporting of data rendered many outcomes unusable. We were unable to undertake meta-analysis. Overall results were limited and inconclusive with no significant differences between treatment groups for hospital admission, mental state, behaviour, social skills or leaving the study early. No data were presented for global state, quality of life or satisfaction. We found insufficient evidence to confirm or refute the benefits of problem solving therapy as an additional

  17. Genetics problem solving and worldview

    Science.gov (United States)

    Dale, Esther

    The research goal was to determine whether worldview relates to traditional and real-world genetics problem solving. Traditionally, scientific literacy emphasized content knowledge alone because it was sufficient to solve traditional problems. The contemporary definition of scientific literacy is, "The knowledge and understanding of scientific concepts and processes required for personal decision-making, participation in civic and cultural affairs and economic productivity" (NRC, 1996). An expanded definition of scientific literacy is needed to solve socioscientific issues (SSI), complex social issues with conceptual, procedural, or technological associations with science. Teaching content knowledge alone assumes that students will find the scientific explanation of a phenomenon to be superior to a non-science explanation. Formal science and everyday ways of thinking about science are two different cultures (Palmer, 1999). Students address this rift with cognitive apartheid, the boxing away of science knowledge from other types of knowledge (Jedege & Aikenhead, 1999). By addressing worldview, cognitive apartheid may decrease and scientific literacy may increase. Introductory biology students at the University of Minnesota during fall semester 2005 completed a written questionnaire-including a genetics content-knowledge test, four genetic dilemmas, the Worldview Assessment Instrument (WAI) and some items about demographics and religiosity. Six students responded to the interview protocol. Based on statistical analysis and interview data, this study concluded the following: (1) Worldview, in the form of metaphysics, relates to solving traditional genetic dilemmas. (2) Worldview, in the form of agency, relates to solving traditional genetics problems. (3) Thus, worldview must be addressed in curriculum, instruction, and assessment.

  18. Solar Coronal Plumes

    Directory of Open Access Journals (Sweden)

    Giannina Poletto

    2015-12-01

    Full Text Available Polar plumes are thin long ray-like structures that project beyond the limb of the Sun polar regions, maintaining their identity over distances of several solar radii. Plumes have been first observed in white-light (WL images of the Sun, but, with the advent of the space era, they have been identified also in X-ray and UV wavelengths (XUV and, possibly, even in in situ data. This review traces the history of plumes, from the time they have been first imaged, to the complex means by which nowadays we attempt to reconstruct their 3-D structure. Spectroscopic techniques allowed us also to infer the physical parameters of plumes and estimate their electron and kinetic temperatures and their densities. However, perhaps the most interesting problem we need to solve is the role they cover in the solar wind origin and acceleration: Does the solar wind emanate from plumes or from the ambient coronal hole wherein they are embedded? Do plumes have a role in solar wind acceleration and mass loading? Answers to these questions are still somewhat ambiguous and theoretical modeling does not provide definite answers either. Recent data, with an unprecedented high spatial and temporal resolution, provide new information on the fine structure of plumes, their temporal evolution and relationship with other transient phenomena that may shed further light on these elusive features.

  19. Service Recovery Paradox In Indian Banking Industry: An Empirical Investigation

    Directory of Open Access Journals (Sweden)

    Arunesh Garg

    2013-11-01

    Full Text Available Normal 0 false false false IN X-NONE X-NONE MicrosoftInternetExplorer4 The present study examines existence of service recovery paradox in Indian banking industry. The study is taken up in the tri-city of Chandigarh, Panchkula and Mohali. The respondents are categorized into failure and no-failure groups on the basis of their service experience. Failure group constitutes those respondents who have experienced service recovery, and has been further divided into five sub-groups ranging from service recovery++ (service recovery better than expected to service recovery- - (service recovery worse than expected. Service recovery paradox is examined by comparing service recovery++ group with no-failure group. The study shows evidence for existence of service recovery paradox in relation to satisfaction. It has been concluded that for service recovery paradox to exist, recovery effort has to be exceptionally good and much better than expectation level of the customer. The study suggests that service managers should take service failure as an opportunity to appease customers by providing a much better than expected recovery experience. However, organizations should not plan to create service failure situations because if they falter on imparting the recovery, customer satisfaction may be influenced negatively. Keywords: Banking, service failure, customer satisfaction, recommendation intention, service recovery, recovery paradox. /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso

  20. Battling Arrow's Paradox to Discover Robust Water Management Alternatives

    Science.gov (United States)

    Kasprzyk, J. R.; Reed, P. M.; Hadka, D.

    2013-12-01

    This study explores whether or not Arrow's Impossibility Theorem, a theory of social choice, affects the formulation of water resources systems planning problems. The theorem discusses creating an aggregation function for voters choosing from more than three alternatives for society. The Impossibility Theorem is also called Arrow's Paradox, because when trying to add more voters, a single individual's preference will dictate the optimal group decision. In the context of water resources planning, our study is motivated by recent theoretical work that has generalized the insights for Arrow's Paradox to the design of complex engineered systems. In this framing of the paradox, states of society are equivalent to water planning or design alternatives, and the voters are equivalent to multiple planning objectives (e.g. minimizing cost or maximizing performance). Seen from this point of view, multi-objective water planning problems are functionally equivalent to the social choice problem described above. Traditional solutions to such multi-objective problems aggregate multiple performance measures into a single mathematical objective. The Theorem implies that a subset of performance concerns will inadvertently dictate the overall design evaluations in unpredictable ways using such an aggregation. We suggest that instead of aggregation, an explicit many-objective approach to water planning can help overcome the challenges posed by Arrow's Paradox. Many-objective planning explicitly disaggregates measures of performance while supporting the discovery of the planning tradeoffs, employing multiobjective evolutionary algorithms (MOEAs) to find solutions. Using MOEA-based search to address Arrow's Paradox requires that the MOEAs perform robustly with increasing problem complexity, such as adding additional objectives and/or decisions. This study uses comprehensive diagnostic evaluation of MOEA search performance across multiple problem formulations (both aggregated and many

  1. Why the oil companies lost solar

    International Nuclear Information System (INIS)

    Miller, Damian

    2013-01-01

    Solar energy is a growing source of electricity supply. Oil companies including BP and Shell recognized this early on and entered the solar industry when it was still in its relative infancy. These companies invested heavily in vertically integrated solar companies that were at one point among the largest in the world. But neither BP nor Shell was successful, and they both decided to exit the solar market. This stands as a paradox since such companies have the funds, the long-term perspectives, the management systems, the multinational presence and the lobbying clout to potentially succeed in this new energy industry. Why were they not successful, and why did they ultimately exit? This paper uses innovation theory to explore the reasons why large incumbent corporations typically fail to succeed in commercializing disruptive innovations at scale. Evidence from semi-structured interviews and discussions with former employees of BP Solar and Shell Solar confirm the explanatory power of key constructs from innovation theory in accounting for the big oil companies' experience with solar technology. Ultimately, the findings suggest that oil companies would have done better to treat their solar businesses as separate stand-alone entities. - Highlights: • This paper examines why BP and Shell were not successful in solar, and exited. • It finds innovation theory to be very helpful in answering the question. • The evidence from semi-structured interviews, press reports, and archival documentation is in line with innovation theory. • Both the theory and the findings offer a different way forward for future oil and gas entrants

  2. Relativistic Archimedes law for fast moving bodies and the general-relativistic resolution of the 'submarine paradox'

    International Nuclear Information System (INIS)

    Matsas, George E. A.

    2003-01-01

    We investigate and solve in the context of general relativity the apparent paradox which appears when bodies floating in a background fluid are set in relativistic motion. Suppose some macroscopic body, say, a submarine designed to lie just in equilibrium when it rests (totally) immersed in a certain background fluid. The puzzle arises when different observers are asked to describe what is expected to happen when the submarine is given some high velocity parallel to the direction of the fluid surface. On the one hand, according to observers at rest with the fluid, the submarine would contract and, thus, sink as a consequence of the density increase. On the other hand, mariners at rest with the submarine using an analogous reasoning for the fluid elements would reach the opposite conclusion. The general relativistic extension of the Archimedes law for moving bodies shows that the submarine sinks. As an extra bonus, this problem suggests a new gedankenexperiment for the generalized second law of thermodynamics

  3. Energy flow in a bound electromagnetic field: resolution of apparent paradoxes

    International Nuclear Information System (INIS)

    Kholmetskii, A L; Yarman, T

    2008-01-01

    In this paper, we present a resolution of apparent paradoxes formulated in (Kholmetskii A L 2006 Apparent paradoxes in classical electrodynamics: the energy-momentum conservation law for a bound electromagnetic field Eur. J. Phys. 27 825-38; Kholmetskii A L and Yarman T 2008 Apparent paradoxes in classical electrodynamics: a fluid medium in an electromagnetic field Eur. J. Phys. 29 1127) and dealing with the energy flux in a bound electromagnetic field

  4. On Hardy's paradox, weak measurements, and multitasking diagrams

    Energy Technology Data Exchange (ETDEWEB)

    Meglicki, Zdzislaw, E-mail: gustav@indiana.edu [Indiana University, Office of the Vice President for Information Technology, 601 E. Kirkwood Ave., Room 116, Bloomington, IN 47405-1223 (United States)

    2011-07-04

    We discuss Hardy's paradox and weak measurements by using multitasking diagrams, which are introduced to illustrate the progress of quantum probabilities through the double interferometer system. We explain how Hardy's paradox is avoided and elaborate on the outcome of weak measurements in this context. -- Highlights: → Hardy's paradox explained and eliminated. → Weak measurements: what is really measured? → Multitasking diagrams: introduced and used to discuss quantum mechanical processes.

  5. Perspectives on Games, Computers, and Mental Health: Questions about Paradoxes, Evidences, and Challenges

    OpenAIRE

    Desseilles, Martin

    2016-01-01

    In the field of mental health, games and computerized games present questions about paradoxes, evidences, and challenges. This perspective article offers perspectives and personal opinion about these questions, evidences, and challenges with an objective of presenting several ideas and issues in this rapidly developing field. First, games raise some questions in the sense of the paradox between a game and an issue, as well as the paradox of using an amusing game to treat a serious pathology. ...

  6. Qualities and Inequalities in Online Social Networks through the Lens of the Generalized Friendship Paradox

    OpenAIRE

    Momeni, Naghmeh; Rabbat, Michael

    2016-01-01

    The friendship paradox is the phenomenon that in social networks, people on average have fewer friends than their friends do. The generalized friendship paradox is an extension to attributes other than the number of friends. The friendship paradox and its generalized version have gathered recent attention due to the information they provide about network structure and local inequalities. In this paper, we propose several measures of nodal qualities which capture different aspects of their act...

  7. Solar Photovoltaic

    OpenAIRE

    Wang, Chen; Lu, Yuefeng

    2016-01-01

    In the 21st century, human demand for new energy sources is urgent, because the traditional fossil energy is unable to meet human needs, and the fossil resource will make pollution, in this situation, solar energy gradually into the vision of scientists. As science advances, humans can already extensive use of solar energy to generate electricity. Solar energy is an inexhaustible and clean energy. In the global energy crisis, environmental pollution is the growing problem of today. The us...

  8. Solar magnetohydrodynamics

    International Nuclear Information System (INIS)

    Priest, E.R.

    1982-01-01

    The book serves several purposes. First set of chapters gives a concise general introduction to solar physics. In a second set the basic methods of magnetohydrodynamics are developed. A third set of chapters is an account of current theories for observed phenomena. The book is suitable for a course in solar physics and it also provides a comprehensive review of present magnetohydrodynamical models in solar physics. (SC)

  9. SHA-1, SAT-solving, and CNF

    CSIR Research Space (South Africa)

    Motara, YM

    2017-09-01

    Full Text Available the intersection between the SHA-1 preimage problem, the encoding of that problem for SAT-solving, and SAT-solving. The results demonstrate that SAT-solving is not yet a viable approach to take to solve the preimage problem, and also indicate that some...

  10. Assessing Algebraic Solving Ability: A Theoretical Framework

    Science.gov (United States)

    Lian, Lim Hooi; Yew, Wun Thiam

    2012-01-01

    Algebraic solving ability had been discussed by many educators and researchers. There exists no definite definition for algebraic solving ability as it can be viewed from different perspectives. In this paper, the nature of algebraic solving ability in terms of algebraic processes that demonstrate the ability in solving algebraic problem is…

  11. Solar constraints

    International Nuclear Information System (INIS)

    Provost, J.

    1984-01-01

    Accurate tests of the theory of stellar structure and evolution are available from the Sun's observations. The solar constraints are reviewed, with a special attention to the recent progress in observing global solar oscillations. Each constraint is sensitive to a given region of the Sun. The present solar models (standard, low Z, mixed) are discussed with respect to neutrino flux, low and high degree five-minute oscillations and low degree internal gravity modes. It appears that actually there do not exist solar models able to fully account for all the observed quantities. (Auth.)

  12. Solar Simulator

    Science.gov (United States)

    1981-01-01

    Oriel Corporation's simulators have a high pressure xenon lamp whose reflected light is processed by an optical system to produce a uniform solar beam. Because of many different types of applications, the simulators must be adjustable to replicate many different areas of the solar radiation spectrum. Simulators are laboratory tools for such purposes as testing and calibrating solar cells, or other solar energy systems, testing dyes, paints and pigments, pharmaceuticals and cosmetic preparations, plant and animal studies, food and agriculture studies and oceanographic research.

  13. Methods of solving nonstandard problems

    CERN Document Server

    Grigorieva, Ellina

    2015-01-01

    This book, written by an accomplished female mathematician, is the second to explore nonstandard mathematical problems – those that are not directly solved by standard mathematical methods but instead rely on insight and the synthesis of a variety of mathematical ideas.   It promotes mental activity as well as greater mathematical skills, and is an ideal resource for successful preparation for the mathematics Olympiad. Numerous strategies and techniques are presented that can be used to solve intriguing and challenging problems of the type often found in competitions.  The author uses a friendly, non-intimidating approach to emphasize connections between different fields of mathematics and often proposes several different ways to attack the same problem.  Topics covered include functions and their properties, polynomials, trigonometric and transcendental equations and inequalities, optimization, differential equations, nonlinear systems, and word problems.   Over 360 problems are included with hints, ...

  14. Confluent-Functional solving systems

    Directory of Open Access Journals (Sweden)

    V.N. Koval

    2001-08-01

    Full Text Available The paper proposes a statistical knowledge-acquision approach. The solving systems are considered, which are able to find unknown structural dependences between situational and transforming variables on the basis of statistically analyzed input information. Situational variables describe features, states and relations between environment objects. Transforming variables describe transforming influences, exerted by a goal-oriented system onto an environment. Unknown environment rules are simulated by a structural equations system, associating situational and transforming variables.

  15. Evaluation of Paradoxical Septal Motion Following Cardiac Surgery with Gated Cardiac Blood Pool Scan

    International Nuclear Information System (INIS)

    Shin, Seong Hae; Chung, June Key; Lee, Myung Chul; Cho, Bo Youn; Koh, Chang Soon; Suh, Kyung Phil

    1985-01-01

    The development of paradoxical interventricular septal motion is a common consequence of cardiopulmonary bypass operation. The reason for this postoperative abnormal septal motion is not clear. 41 patients were studied preoperatively and postoperatively with radionuclide blood pool scan to evaluate the frequency of development of paradoxical septal motion with right ventricular volume overload before surgery and the frequency of development of paradoxical septal motion after cardiac surgery with cardiopulmonary bypass, and to evaluate the change of EF related to the development of paradoxical septal motion after cardiac surgery. The results were as follows; 1) 7 of 41 patients with right ventricular volume overload (that is 17%) showed paradoxical septal motion before surgery. But 13 of 34 patients (that is 42%) had paradoxical septal motion after cardiac surgery with cardiopulmonary bypass. So open heart surgery with cardiopulmonary bypass related the development of paradoxical septal motion after surgery. 2) EF significantly decreased in patients who developed paradoxical septal motion after surgery, whereas the EF did not change in the patients who retained normal interventricular septal motion after surgery. So paradoxical septal motion usually reflected some diminution of left ventricular function, immediately after cardiac surgery.

  16. Evaluation of Paradoxical Septal Motion Following Cardiac Surgery with Gated Cardiac Blood Pool Scan

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Seong Hae; Chung, June Key; Lee, Myung Chul; Cho, Bo Youn; Koh, Chang Soon; Suh, Kyung Phil [Seoul National University College of Medicine, Seoul (Korea, Republic of)

    1985-03-15

    The development of paradoxical interventricular septal motion is a common consequence of cardiopulmonary bypass operation. The reason for this postoperative abnormal septal motion is not clear. 41 patients were studied preoperatively and postoperatively with radionuclide blood pool scan to evaluate the frequency of development of paradoxical septal motion with right ventricular volume overload before surgery and the frequency of development of paradoxical septal motion after cardiac surgery with cardiopulmonary bypass, and to evaluate the change of EF related to the development of paradoxical septal motion after cardiac surgery. The results were as follows; 1) 7 of 41 patients with right ventricular volume overload (that is 17%) showed paradoxical septal motion before surgery. But 13 of 34 patients (that is 42%) had paradoxical septal motion after cardiac surgery with cardiopulmonary bypass. So open heart surgery with cardiopulmonary bypass related the development of paradoxical septal motion after surgery. 2) EF significantly decreased in patients who developed paradoxical septal motion after surgery, whereas the EF did not change in the patients who retained normal interventricular septal motion after surgery. So paradoxical septal motion usually reflected some diminution of left ventricular function, immediately after cardiac surgery.

  17. Solar cooking

    Science.gov (United States)

    Over two billion people face fuel wood shortages, causing tremendous personal and environmental stress. Over 4 million people die prematurely from indoor air pollution. Solar cooking can reduce fuel wood consumption and indoor air pollution. Solar cooking has been practiced and published since th...

  18. Solar Sprint

    Science.gov (United States)

    Tabor, Richard; Anderson, Stephen

    2007-01-01

    In the "Solar Sprint" activity, students design, test, and race a solar-powered car built with Legos. The use of ratios is incorporated to simulate the actual work of scientists and engineers. This method encourages fourth-grade students to think about multiple variables and stimulates their curiosity when an activity doesn't come out as…

  19. Colonic epithelial cell activation and the paradoxical effects of butyrate.

    Science.gov (United States)

    Gibson, P R; Rosella, O; Wilson, A J; Mariadason, J M; Rickard, K; Byron, K; Barkla, D H

    1999-04-01

    Butyrate may have paradoxical effects on epithelial cells of similar origin. This study aimed to examine the hypothesis that one mechanism that dictates a cell's response to butyrate is its state of activation. First, the responses to 24 h exposure to butyrate (1-2 mM) of normal and neoplastic human colonic epithelial cells activated by their isolation and primary culture, and of colon cancer cell lines, LIM1215 and Caco-2, were examined. In primary cultures of normal and cancer cells, butyrate had no effect on alkaline phosphatase activities but significantly suppressed urokinase receptor expression by a mean +/- SEM of 30 +/- 12% and 36 +/- 9%, respectively. Interleukin-8 secretion was suppressed by 44 +/- 7% in normal cells (P 50%, urokinase receptor expression >2-fold and interleukin-8 secretion >3-fold in response to butyrate. Secondly, the effect of butyrate on Caco-2 cells was examined with or without prior exposure to a specific activating stimulus [tumour necrosis factor alpha (TNF alpha)]. Interleukin-8 secretion increased by 145 +/- 23% and 132 +/- 17% on 24 h exposure to 2 mM butyrate or 0.1 microM TNF alpha alone, respectively. However, in cells pre-treated with TNF alpha, butyrate significantly inhibited secretion by 34 +/- 7% below unstimulated levels. The response to butyrate of urokinase receptor, whose expression was not stimulated by TNF alpha, was unchanged. These effects were mimicked by trichostatin A, an inhibitor of histone deacetylase, suggesting that butyrate's paradoxical effects may have been operating by the same mechanism. In conclusion, some of the paradoxical effects of butyrate do not appear to represent inherent differences between normal and transformed cells. Rather, the response may be determined by the state of activation of the cells.

  20. The three paradoxes of patient flow: an explanatory case study.

    Science.gov (United States)

    Kreindler, Sara A

    2017-07-12

    Health systems in many jurisdictions struggle to reduce Emergency Department congestion and improve patient flow across the continuum of care. Flow is often described as a systemic issue requiring a "system approach"; however, the implications of this idea remain poorly understood. Focusing on a Canadian regional health system whose flow problems have been particularly intractable, this study sought to determine what system-level flaws impede healthcare organizations from improving flow. This study drew primarily on qualitative data from in-depth interviews with 62 senior, middle and departmental managers representing the Region, its programs and sites; quantitative analysis of key flow indicators (1999-2012) and review of ~700 documents furnished important context. Examination of the interview data revealed that the most striking feature of the dataset was contradiction; accordingly, a technique of dialectical analysis was developed to examine observed contradictions at successively deeper levels. Analysis uncovered three paradoxes: "Many Small Successes and One Big Failure" (initiatives improve parts of the system but fail to fix underlying system constraints); "Your Innovation Is My Aggravation" (local innovation clashes with regional integration); and most critically, "Your Order Is My Chaos" (rules that improve service organization for my patients create obstacles for yours). This last emerges when some entities (sites/hospitals) define their patients in terms of their location in the system, while others (regional programs) define them in terms of their needs/characteristics. As accountability for improving flow was distributed among groups that thus variously defined their patients, local efforts achieved little for the overall system, and often clashed with each other. These paradoxes are indicative of a fundamental antagonism between the system's parts and the whole. An accretion of flow initiatives in all parts of the system will never add up to a system