WorldWideScience

Sample records for argument large permittivity

  1. Metamaterials and the Landau-Lifshitz permeability argument: large permittivity begets high-frequency magnetism.

    Science.gov (United States)

    Merlin, Roberto

    2009-02-10

    Homogeneous composites, or metamaterials, made of dielectric or metallic particles are known to show magnetic properties that contradict arguments by Landau and Lifshitz [Landau LD, Lifshitz EM (1960) Electrodynamics of Continuous Media (Pergamon, Oxford, UK), p 251], indicating that the magnetization and, thus, the permeability, loses its meaning at relatively low frequencies. Here, we show that these arguments do not apply to composites made of substances with Im square root(epsilon(S)) > lambda/l or Re square root(epsilon(S)) approximately lambda/l (epsilon(S) and l are the complex permittivity and the characteristic length of the particles, and lambda > l is the vacuum wavelength). Our general analysis is supported by studies of split rings, one of the most common constituents of electromagnetic metamaterials, and spherical inclusions. An analytical solution is given to the problem of scattering by a small and thin split ring of arbitrary permittivity. Results reveal a close relationship between epsilon(S) and the dynamic magnetic properties of metamaterials. For |square root(epsilon(S))| magnetic activity, consistent with the Landau-Lifshitz argument and similar to that of molecular crystals. In contrast, large values of the permittivity lead to strong diamagnetic or paramagnetic behavior characterized by susceptibilities whose magnitude is significantly larger than that of natural substances. We compiled from the literature a list of materials that show high permittivity at wavelengths in the range 0.3-3000 microm. Calculations for a system of spherical inclusions made of these materials, using the magnetic counterpart to Lorentz-Lorenz formula, uncover large magnetic effects the strength of which diminishes with decreasing wavelength.

  2. Large dielectric permittivity in the paraelectric RMn2O5 with R=Tb, Dy, and Er

    Science.gov (United States)

    Han, T. C.; Lin, J. G.; Kuo, K. M.; Chern, G.

    2008-04-01

    The complex dielectric permittivities (ɛ',ɛ″) of RMn2O5 (R =Tb, Dy, and Er) are measured in the temperature range of 78-328 K with frequencies ranging from 100 Hz to 1 MHz. A large real part of the dielectric constant ɛ' (40-140) is observed at room temperature in all three samples studied. These values are higher than the peak value found at the ferroelectric transition of RMn2O5 single crystals. Our results reveal that high dielectric permittivities are related to thermally activated dipolar motions with activation energies of ˜300 meV and a relaxation frequency of ˜3×1012 Hz. The possible relation between the high dielectric permittivity and the size effect of R ions based on the spin-phonon interaction is suggested.

  3. Jumping on Thin Ice: Values Argument Writing Assignment for a Large Enrollment Plant Science Class.

    Science.gov (United States)

    Grabau, Larry J.; Wilson, Patricia S.

    1995-01-01

    Documents an evolving attempt to manage a values argument writing assignment in a large enrollment plant science class. Explores how developing library skills improved students' writing. Contains 22 references. (DDR)

  4. No Winglets: What a Drag...Argument for Adding Winglets to Large Air Force Aircraft

    Science.gov (United States)

    2008-01-01

    22134-5068 MASTER OF MILITARY STUDIES NO WINGLETS : WHAT A DRAG... ARGUMENT FOR ADDING WINGLETS TO LARGE AIR FORCE AIRCRAFT ,SUBMITTED IN PARTIAL...currently valid OMB control number. 1. REPORT DATE 2008 2. REPORT TYPE 3. DATES COVERED 00-00-2008 to 00-00-2008 4. TITLE AND SUBTITLE No Winglets ...What a Drag...Argument for Adding Winglets to Large Air Force Aircraft 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR

  5. Large dielectric permittivity and possible correlation between magnetic and dielectric properties in bulk BaFeO{sub 3−δ}

    Energy Technology Data Exchange (ETDEWEB)

    Sagdeo, Archna; Gautam, Kamini; Singh, M. N.; Sinha, A. K.; Ghosh, Haranath; Ganguli, Tapas; Chakrabarti, Aparna [Indus Synchrotrons Utilization Division, Raja Ramanna Center for Advanced Technology, Indore 13 (India); Sagdeo, P. R. [Discipline of Physics and MSE, Indian Institute of Technology, Indore 17 (India); Gupta, S. M. [Laser Materials Development and Devices Division, Raja Ramanna Centre for Advanced Technology, Indore 13 (India); Nigam, A. K. [Tata Institute of Fundamental Research, Homi Bhabha Road, Mumbai 05 (India); Rawat, Rajeev [UGC-DAE Consortium for Scientific Research, University Campus, Khandwa Road, Indore 17 (India)

    2014-07-28

    We report structural, magnetic, and dielectric properties of oxygen deficient hexagonal BaFeO{sub 3−δ}. A large dielectric permittivity comparable to that of other semiconducting oxides is observed in BaFeO{sub 3−δ}. Magnetization measurements indicate magnetic inhomogeneity and the system shows a paramagnetic to antiferromagnetic transition at ∼160 K. Remarkably, the temperature, at which paramagnetic to antiferromagnetic transition occurs, around this temperature, a huge drop in the dissipation factor takes place and resistivity shoots up; this indicates the possible correlation among magnetic and dielectric properties. First principle simulations reveal that some of these behaviors may be explained in terms of many body electron correlation effect in the presence of oxygen vacancy present in BaFeO{sub 3−δ} indicating its importance in both fundamental science as well as in applications.

  6. Nanodielectrics with giant permittivity

    Indian Academy of Sciences (India)

    S K Saha

    2008-06-01

    Nanodielectrics is an emerging area of research because of its potential application in energy storage and transducers. One-dimensional metallic nanostructures with localized electronic wave functions show giant dielectric constant. Following the prediction, during the last couple of years we have investigated the effect of giant permittivity in one-dimensional systems of conventional metals and conjugated polymer chains. In this article, we have tried to summarize the works on giant permittivity and finally the fabrication of nanocapacitor using metal nanowires, which shows giant permittivity is also discussed.

  7. Biofilm monitoring using complex permittivity.

    Energy Technology Data Exchange (ETDEWEB)

    Altman, Susan Jeanne; McGrath, Lucas K.; Dolan, Patricia L.; Yelton, William Graham

    2008-10-01

    is observed two hours after inoculation when the permittivity begins to increase slightly over the next 20 hours, best seen in the shift from 1000 Hz to 5000 Hz in tan {delta} at the high frequencies (c). Because of similar dielectric relaxation properties noted by the comparable size of the semicircles, plot (a), and the height of tan {delta}, plot (c), within the first 29 hours, cell activity levels did not appreciably change. The third trend is observed when the complex permittivity value drops by orders of magnitude between 29 hours and 37 hours, best seen in the log [E] plot (b), and in the drop of the dielectric loss, tan {delta}, to 0. This change in the dielectric properties in the bio environment is nearly independent of all frequencies (c) and dissimilar from the original condition when only bacteria and nutrient was present in the biofilm chambers. The semicircles in plot (a) for this period decreased below the resolution of the graph, implying a large difference in the dielectric behavior of the cells/biofilms consisting of low dielectric losses. We believe these large changes are related to the on-set of biofilms.

  8. Test plan for prototype dielectric permittivity sensor

    Energy Technology Data Exchange (ETDEWEB)

    Pfeifer, M.C.

    1993-07-01

    The digface characterization project funded by the Buried Waste Integrated Demonstration (BWID) is designed to test a new method of monitoring hazardous conditions during the remediation at waste sites. Often on a large scale, the exact cause of each anomaly is difficult to determine and ambiguities remain in the characterization of a site. The digface characterization concept is designed to alleviate some of this uncertainty by creating systems that monitor small volumes of soil and detect anomalous areas during remediation before they are encountered. The goal of the digface characterization demonstration is to detect changes in the physical properties from one volume to another and relate these changes in physical properties to changes in the level of contamination. Dielectric permittivity mapping is a method that might prove useful in digface characterization. In this project, the role of a dielectric permittivity monitoring device is under investigation. This project addresses two issues: what are the optimal means of mapping dielectric permittivity contrasts and what types of targets can be detected using dielectric permittivity mapping.

  9. Multiband Negative Permittivity Metamaterials and Absorbers

    Directory of Open Access Journals (Sweden)

    Yiran Tian

    2013-01-01

    Full Text Available Design and characteristics of multiband negative permittivity metamaterial and its absorber configuration are presented in this paper. The proposed multiband metamaterial is composed of a novel multibranch resonator which can possess four electric resonance frequencies. It is shown that, by controlling the length of the main branches of such resonator, the resonant frequencies and corresponding absorbing bands of metamaterial absorber can be shifted in a large frequency band.

  10. What Is the Optimal Treatment of Large Brain Metastases? An Argument for a Multidisciplinary Approach

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Clara Y.H.; Chang, Steven D. [Department of Neurosurgery, Stanford University Medical Center, Stanford, California (United States); Gibbs, Iris C. [Department of Radiation Oncology, Stanford University Medical Center, Stanford, California (United States); Adler, John R.; Harsh, Griffith R. [Department of Neurosurgery, Stanford University Medical Center, Stanford, California (United States); Atalar, Banu [Department of Radiation Oncology, Acibadem University School of Medicine, Istanbul (Turkey); Lieberson, Robert E. [Department of Neurosurgery, Stanford University Medical Center, Stanford, California (United States); Soltys, Scott G., E-mail: sgsoltys@stanford.edu [Department of Radiation Oncology, Stanford University Medical Center, Stanford, California (United States)

    2012-11-01

    Purpose: Single-modality treatment of large brain metastases (>2 cm) with whole-brain irradiation, stereotactic radiosurgery (SRS) alone, or surgery alone is not effective, with local failure (LF) rates of 50% to 90%. Our goal was to improve local control (LC) by using multimodality therapy of surgery and adjuvant SRS targeting the resection cavity. Patients and Methods: We retrospectively evaluated 97 patients with brain metastases >2 cm in diameter treated with surgery and cavity SRS. Local and distant brain failure (DF) rates were analyzed with competing risk analysis, with death as a competing risk. The overall survival rate was calculated by the Kaplain-Meier product-limit method. Results: The median imaging follow-up duration for all patients was 10 months (range, 1-80 months). The 12-month cumulative incidence rates of LF, with death as a competing risk, were 9.3% (95% confidence interval [CI], 4.5%-16.1%), and the median time to LF was 6 months (range, 3-17 months). The 12-month cumulative incidence rate of DF, with death as a competing risk, was 53% (95% CI, 43%-63%). The median survival time for all patients was 15.6 months. The median survival times for recursive partitioning analysis classes 1, 2, and 3 were 33.8, 13.7, and 9.0 months, respectively (p = 0.022). On multivariate analysis, Karnofsky Performance Status ({>=}80 vs. <80; hazard ratio 0.54; 95% CI 0.31-0.94; p = 0.029) and maximum preoperative tumor diameter (hazard ratio 1.41; 95% CI 1.08-1.85; p = 0.013) were associated with survival. Five patients (5%) required intervention for Common Terminology Criteria for Adverse Events v4.02 grade 2 and 3 toxicity. Conclusion: Surgery and adjuvant resection cavity SRS yields excellent LC of large brain metastases. Compared with other multimodality treatment options, this approach allows patients to avoid or delay whole-brain irradiation without compromising LC.

  11. The argument of mathematics

    CERN Document Server

    Aberdein, Andrew

    2014-01-01

    This book presents a comprehensive investigation into the relationship between argumentation theory and the philosophy of mathematical practice. It offers large array of examples ranging from the history of mathematics to formal proof verification.

  12. Family Arguments

    Science.gov (United States)

    ... Spread the Word Shop AAP Find a Pediatrician Family Life Medical Home Family Dynamics Adoption & Foster Care ... Life Listen Español Text Size Email Print Share Family Arguments Page Content Article Body We seem to ...

  13. Temperature-dependent permittivity of annealed and unannealed gold films

    CERN Document Server

    Shen, Po-Ting; Lin, Cheng-Wei; Liu, Hsiang-Lin; Chang, Chih-Wei; Chu, Shi-Wei

    2016-01-01

    Due to local field enhancement and subwavelength confinements, nano-plasmonics provide numerous novel applications. Simultaneously, as an efficient nanoscale heat generator from inherent absorption, thermo-plasmonics is emerging as an important branch. However, although significant temperature increase is involved in applications, detailed characterization of metal permittivity at different temperatures is lacking. In this work, we extract the permittivity of gold film from 300K to the annealing temperature of 570K. By comparing annealed and unannealed films, more than one-order difference in thermo-derivative of permittivity is revealed, resulting in unexpectedly large variation of plasmonic properties. Our result is valuable not only for characterizing extensively used unannealed nanoparticles, but also for designing future thermo-nano-plasmonic systems.

  14. High permittivity gate dielectric materials

    CERN Document Server

    2013-01-01

    "The book comprehensively covers all the current and the emerging areas of the physics and the technology of high permittivity gate dielectric materials, including, topics such as MOSFET basics and characteristics, hafnium-based gate dielectric materials, Hf-based gate dielectric processing, metal gate electrodes, flat-band and threshold voltage tuning, channel mobility, high-k gate stack degradation and reliability, lanthanide-based high-k gate stack materials, ternary hafnia and lanthania based high-k gate stack films, crystalline high-k oxides, high mobility substrates, and parameter extraction. Each chapter begins with the basics necessary for understanding the topic, followed by a comprehensive review of the literature, and ultimately graduating to the current status of the technology and our scientific understanding and the future prospects."

  15. Undignified Arguments.

    Science.gov (United States)

    Holm, Søren

    2016-04-01

    Something strange has happened to the concept of dignity in bioethics. After a long period in which U.S. pragmatist and U.K. consequentialist philosophers have argued that the concept is useless and vacuous, and in which they have been reasonably successful in expunging it from mainstream English-language academic bioethics, dignity has suddenly become popular again in debates about the legalization of physician-assisted dying (PAD). And, even stranger, it is deployed not by conservatives but by liberals. In the debates about PAD, liberal proponents of legalization seem to accept without question that there is such a state or process as "death with dignity," which is juxtaposed to "undignified dying." It also seems to be accepted that both of these states can be fairly easily identified and that they carry great moral weight. This article provides an analysis of the current resurgence of "undignified" arguments and argues on the basis of that analysis (1) that a proper understanding of the concept of dignity shows that the previous reductive arguments against dignity are partially incomplete and therefore partially misguided and (2) that, despite dignity having meaning, the idea of an undignified death cannot carry the moral weight it is given by proponents of the legalization of PAD.

  16. THE ARGUMENTATION IN GALATIANS

    African Journals Online (AJOL)

    argumentation theory has been modest and no full-fledged argumentation analyses of. Paul's argumentation ... nication, Argumentation Theory and Rhetoric; Department of Exegesis, Åbo. Akademi ...... Dordrecht (Holland) &. Cinnaminson ...

  17. Permittivity measurements in solids, powders, and liquids

    Science.gov (United States)

    Thompson, Frank

    2005-08-01

    A microwave waveguide cell has been constructed to facilitate the measurement of permittivity on solids, powders, and liquids. By employing this cell and a vector network analyzer, permittivity values have been obtained, at room temperature, for samples of perspex, PTFE, sand, and sunflower oil. These values are in agreement with published data. It is hoped that this experiment will provide students with an opportunity to use modern microwave instrumentation and gain a greater appreciation of the physical properties of materials.

  18. Estimation of complex permittivity using loop antenna

    DEFF Research Database (Denmark)

    Lenler-Eriksen, Hans-Rudolph; Meincke, Peter

    2004-01-01

    A method for estimating the complex permittivity of materials in the vicinity of a loop antenna is proposed. The method is based on comparing measured and numerically calculated input admittances for the loop antenna.......A method for estimating the complex permittivity of materials in the vicinity of a loop antenna is proposed. The method is based on comparing measured and numerically calculated input admittances for the loop antenna....

  19. Estimation of complex permittivity using loop antenna

    DEFF Research Database (Denmark)

    Lenler-Eriksen, Hans-Rudolph; Meincke, Peter

    2004-01-01

    A method for estimating the complex permittivity of materials in the vicinity of a loop antenna is proposed. The method is based on comparing measured and numerically calculated input admittances for the loop antenna.......A method for estimating the complex permittivity of materials in the vicinity of a loop antenna is proposed. The method is based on comparing measured and numerically calculated input admittances for the loop antenna....

  20. Comparison of complex permittivities of isotonic colloids containing single-wall carbon nanotubes of varying chirality.

    Science.gov (United States)

    Nair, Tejas; Symanowski, James T; Gach, H Michael

    2012-02-01

    The application of bio-compatible, conductive nanoparticles in combination with radiofrequency (RF) irradiation to raise tissue temperatures between 40 and 60 °C for hyperthermia and ablation spurred interest in the complex permittivities of isotonic nanoparticle-based colloids. Nanoparticles with large aspect ratios and high permittivities increase the bulk permittivity of the colloid and RF losses at the macroscopic scale. The complex permittivities of isotonic colloids with and without single-wall carbon nanotubes (SWCNTs) containing either metallic, semiconducting, or mixed chiralities were measured from 20 MHz to 1 GHz at room temperature. The colloids were made with one of three different isotonic solvents: phosphate buffered saline (PBS), and Dulbecco's modified eagle medium (DMEM) with and without 0.5% weight/volume bovine serum albumin to simulate cytosol and blood, respectively. The concentration of elemental carbon from the SWCNTs in the colloids ranged from 16 to 17 mM. The permittivities were corrected for electrode polarization effects by fitting the data to the Cole-Cole relaxation model with a constant phase angle element. The presence of SWCNTs increased both the real and imaginary components of the permittivities of the colloids. For all three solvents, the direct current (DC) components of the real and imaginary permittivities were greatest for the colloids containing the mixed chirality SWCNTs, followed by the colloids with semiconducting SWCNTs, and then metallic SWCNTs. Copyright © 2011 Wiley Periodicals, Inc.

  1. Promoting Students' Attention to Argumentative Reasoning Patterns

    Science.gov (United States)

    Cavagnetto, Andy R.; Kurtz, Kenneth J.

    2016-01-01

    Argument-based interventions in science education have largely been motivated by the perspective that students lack knowledge of argument. Recent studies, however, suggest that contextual factors influence students' argument quality. The authors hypothesize that a key limiting factor lies in students' abilities to recognize when to employ…

  2. Effective permittivity of finite inhomogeneous objects

    NARCIS (Netherlands)

    Raghunathan, S.B.; Budko, N.V.

    2010-01-01

    A generalization of the S-parameter retrieval method for finite three-dimensional inhomogeneous objects under arbitrary illumination and observation conditions is presented. The effective permittivity of such objects may be rigorously defined as a solution of a nonlinear inverse scattering problem.

  3. Permittivity spectroscopy - an insight into materials properties.

    Science.gov (United States)

    Stoynov, Zdravko; Mladenova, Emiliya; Levi, Daniela; Vladikova, Daria

    2014-01-01

    Permittivity Spectroscopy is a branch of the Impedance Spectroscopy specially tuned for measurements and analyses of dielectrics permittivity properties. The present paper presents experimental results on permittivity properties of composite objects in which a polarizable dielectric is distributed in a fine non-polarizable matrix (solid or liquid) measured in frequency range 1 MHz down to 0.01 Hz. Two types of objects are studied - water in porous functional ceramics and lubricating oils. In both systems gigantic enhancement of the effective capacitance is observed. The first series of experiments was performed on porous membranes of yttrium doped barium cerate, which is a proton conducting ceramics with hydrophilic properties. At a given level of watering the measured capacitance is sharply increasing (3 to 5 orders of magnitude) in the lower frequency range. The second example covers permittivity study of lubricating oils, where the increase is 2-3 orders of magnitude. The phenomenon of gigantic enhancement of the effective capacitance could be related to a formation of dipole volume structures induced by the external alternating electrical field.

  4. Study of Melon Permittivities for Quality Sensing

    Science.gov (United States)

    ABSTRACT Permittivities (dielectric constants and dielectric loss factors) were determined at frequencies between 10 MHz and 20 GHz for mature cantaloupe, honeydew melons, and watermelons grown during three consecutive years and studied in relation to the sweetness of the edible tissue as determine...

  5. Permittivity and permeability tensors for cloaking applications

    CERN Document Server

    Choudhury, Balamati; Jha, Rakesh Mohan

    2016-01-01

    This book is focused on derivations of analytical expressions for stealth and cloaking applications. An optimal version of electromagnetic (EM) stealth is the design of invisibility cloak of arbitrary shapes in which the EM waves can be controlled within the cloaking shell by introducing a prescribed spatial variation in the constitutive parameters. The promising challenge in design of invisibility cloaks lies in the determination of permittivity and permeability tensors for all the layers. This book provides the detailed derivation of analytical expressions of the permittivity and permeability tensors for various quadric surfaces within the eleven Eisenhart co-ordinate systems. These include the cylinders and the surfaces of revolutions. The analytical modeling and spatial metric for each of these surfaces are provided along with their tensors. This mathematical formulation will help the EM designers to analyze and design of various quadratics and their hybrids, which can eventually lead to design of cloakin...

  6. Abnormal enhancement of electric field inside a thin permittivity-near-zero object in free space

    CERN Document Server

    Jin, Yi; He, Sailing

    2010-01-01

    It is found that the electric field can be enhanced strongly inside a permittivity-near-zero object in free space, when the transverse cross section of the object is small and the length along the propagation direction of the incident wave is large enough as compared with the wavelength. The physical mechanism is explained in details. The incident electromagnetic energy can only flow almost normally through the outer surface into or out of the permittivity-near-zero object, which leads to large energy stream density and then strong electric field inside the object. Meanwhile, the magnetic field inside the permittivity-near-zero object may be smaller than that of the incident wave, which is also helpful for enhancing the electric field. Two permittivity-near-zero objects of simple shapes, namely, a thin cylindrical shell and a long thin rectangular bar, are chosen for numerical illustration. The enhancement of the electric field becomes stronger when the permittivity-near-zero object becomes thinner. The physi...

  7. Measurement of liquid permittivity by solenoid self-resonance

    Science.gov (United States)

    Getz, Patrick; Mazzeo, Brian

    2010-10-01

    Permittivity of a liquid is an important macroscopic property which is dependent on the composition and physical state of the liquid. Measurement of liquid permittivity is usually performed using a parallel-plate capacitor or terminated coaxial line. In this study, a solenoid surrounding a column of liquid is used to measure permittivity changes. The inductance of the solenoid is not greatly affected by permittivity and conductivity changes for small diameters. However, the self-capacitance is greatly affected by changing solution conditions. The self-resonance, due to the changing self-capacitance, thus reveals properties of the solution. This is demonstrated on a variety of liquids with varying permittivity and conductivity.

  8. Polyimide/nanosized CaCu3Ti4O12 functional hybrid films with high dielectric permittivity

    Science.gov (United States)

    Yang, Yang; Zhu, Ben-Peng; Lu, Zhi-Hong; Wang, Zi-Yu; Fei, Chun-Long; Yin, Di; Xiong, Rui; Shi, Jing; Chi, Qing-Guo; Lei, Qing-Quan

    2013-01-01

    This work reports the high dielectric permittivity of polyimide (PI) embedded with CaCu3Ti4O12 (CCTO) nanoparticles. The dielectric behavior has been investigated over a frequency of 100 Hz-1 MHz. High dielectric permittivity (ɛ = 171) and low dielectric loss (tan δ = 0.45) at 100 Hz have been observed near the percolation threshold. The experimental results fit well with the Percolation theory. We suggest that the high dielectric permittivity originates from the large interface area and the remarkable Maxwell-Wagner-Sillars effect at percolation in which nomadic charge carriers are blocked at internal interfaces between CCTO nanoparticles and the polyimide matrix.

  9. Characteristics of Effective Argumentation.

    Science.gov (United States)

    Frana, Adrian W.

    1989-01-01

    Examines how the 1988 Presidential Debates provide a resource for effective instruction in public argument. Provides several examples of effective (and ineffective) argumentative speaking taken from the debates. (MM)

  10. Den gode argumentations anatomi

    DEFF Research Database (Denmark)

    Kock, Christian Erik J

    2013-01-01

    God argumentation har tre dimensioner: Den er faktuelt retvisende, den er relevant, og den er vægtig. Desværre slipper politikerne ofte af sted med mangelfuld argumentation fordi de forklæder den godt. Derfor får du her de vigtigste redskaber til at spotte uskikkene i politisk argumentation...

  11. One-sided arguments

    NARCIS (Netherlands)

    van Laar, J.A.

    2007-01-01

    When is an argument to be called one-sided? When is putting forward such an argument fallacious? How can we develop a model for critical discussion, such that a fallaciously one-sided argument corresponds to a violation of a discussion rule? These issues are dealt with within 'the limits of the dial

  12. Den gode argumentations anatomi

    DEFF Research Database (Denmark)

    Kock, Christian Erik J

    2013-01-01

    God argumentation har tre dimensioner: Den er faktuelt retvisende, den er relevant, og den er vægtig. Desværre slipper politikerne ofte af sted med mangelfuld argumentation fordi de forklæder den godt. Derfor får du her de vigtigste redskaber til at spotte uskikkene i politisk argumentation...

  13. Gyroid Optical Metamaterials: Calculating the Effective Permittivity of Multidomain Samples.

    Science.gov (United States)

    Dolan, James A; Saba, Matthias; Dehmel, Raphael; Gunkel, Ilja; Gu, Yibei; Wiesner, Ulrich; Hess, Ortwin; Wilkinson, Timothy D; Baumberg, Jeremy J; Steiner, Ullrich; Wilts, Bodo D

    2016-10-19

    Gold gyroid optical metamaterials are known to possess a reduced plasma frequency and linear dichroism imparted by their intricate subwavelength single gyroid morphology. The anisotropic optical properties are, however, only evident when a large individual gyroid domain is investigated. Multidomain gyroid metamaterials, fabricated using a polyisoprene-b-polystyrene-b-poly(ethylene oxide) triblock terpolymer and consisting of multiple small gyroid domains with random orientation and handedness, instead exhibit isotropic optical properties. Comparing three effective medium models, we here show that the specular reflectance spectra of such multidomain gyroid optical metamaterials can be accurately modeled over a broad range of incident angles by a Bruggeman effective medium consisting of a random wire array. This model accurately reproduces previously published results tracking the variation in normal incidence reflectance spectra of gold gyroid optical metamaterials as a function of host refractive index and volume fill fraction of gold. The effective permittivity derived from this theory confirms the change in sign of the real part of the permittivity in the visible spectral region (so, that gold gyroid metamaterials exhibit both dielectric and metallic behavior at optical wavelengths). That a Bruggeman effective medium can accurately model the experimental reflectance spectra implies that small multidomain gold gyroid optical metamaterials behave both qualitatively and quantitatively as an amorphous composite of gold and air (i.e., nanoporous gold) and that coherent electromagnetic contributions arising from the subwavelength gyroid symmetry are not dominant.

  14. Gyroid Optical Metamaterials: Calculating the Effective Permittivity of Multidomain Samples

    Science.gov (United States)

    2016-01-01

    Gold gyroid optical metamaterials are known to possess a reduced plasma frequency and linear dichroism imparted by their intricate subwavelength single gyroid morphology. The anisotropic optical properties are, however, only evident when a large individual gyroid domain is investigated. Multidomain gyroid metamaterials, fabricated using a polyisoprene-b-polystyrene-b-poly(ethylene oxide) triblock terpolymer and consisting of multiple small gyroid domains with random orientation and handedness, instead exhibit isotropic optical properties. Comparing three effective medium models, we here show that the specular reflectance spectra of such multidomain gyroid optical metamaterials can be accurately modeled over a broad range of incident angles by a Bruggeman effective medium consisting of a random wire array. This model accurately reproduces previously published results tracking the variation in normal incidence reflectance spectra of gold gyroid optical metamaterials as a function of host refractive index and volume fill fraction of gold. The effective permittivity derived from this theory confirms the change in sign of the real part of the permittivity in the visible spectral region (so, that gold gyroid metamaterials exhibit both dielectric and metallic behavior at optical wavelengths). That a Bruggeman effective medium can accurately model the experimental reflectance spectra implies that small multidomain gold gyroid optical metamaterials behave both qualitatively and quantitatively as an amorphous composite of gold and air (i.e., nanoporous gold) and that coherent electromagnetic contributions arising from the subwavelength gyroid symmetry are not dominant. PMID:27785456

  15. Global permittivity mapping of the Martian surface from SHARAD

    Science.gov (United States)

    Castaldo, Luigi; Mège, Daniel; Gurgurewicz, Joanna; Orosei, Roberto; Alberti, Giovanni

    2017-03-01

    SHARAD is a subsurface sounding radar aboard NASA's Mars Reconnaissance Orbiter, capable of detecting dielectric discontinuities in the subsurface caused by compositional and/or structural changes. Echoes coming from the surface contain information on geometric properties at metre scale and on the permittivity of the upper layers of the Martian crust. A model has been developed to estimate the effect of surface roughness on echo power, depending on statistical parameters such as RMS height and topothesy. Such model is based on the assumption that topography can be characterized as a self-affine fractal, and its use allows the estimation of the dielectric properties of the first few metres of the Martian soil. A permittivity map of the surface of Mars is obtained, covering several large regions across the planet surface. The most significant correspondence with geology is observed at the dichotomy boundary, with high dielectric constant on the highlands side (7 to over 10) and lower on the lowlands side (3 to 7). Other geological correlations are discussed.

  16. Nonresonant Metamaterials with an Ultra-High Permittivity

    Institute of Scientific and Technical Information of China (English)

    HE Xiao-Yang; CHEN Qi; LI Lin-Cui; YANG Chun; LI Biao; ZHOU Bang-Hua; TANG Chuan-Xiang

    2011-01-01

    @@ A nonresonant structure composed of metal cut-wires for realization of metamaterials is proposed.This kind of metamaterial works at an ultra broad bandwidth with uniform permittivity.Theoretical analysis and numerical simulations are carried out to study this inclusion and expression for the effective permittivity is given.Several methods are studied to enhance the permittivity and a nonresonant metamaterial with an ultra-high permittivity is obtained.A demonstration shows that the permittivity of this metamaterial can be as high as 145.%A nonresonant structure composed of metal cut-wires for realization of metamaterials is proposed. This kind of metamaterial works at an ultra broad bandwidth with uniform permittivity. Theoretical analysis and numerical simulations are carried out to study this inclusion and expression for the effective permittivity is given. Several methods are studied to enhance the permittivity and a nonresonant metamaterial with an ultra-high permittivity is obtained. A demonstration shows that the permittivity of this metamaterial can be as high as 145.

  17. Microwave broadband permittivity measurement with a multimode helical resonator for studying catalysts

    Science.gov (United States)

    Roussy, Georges; Thiebaut, Jean-Marie; Ename-Obiang, Francis; Marchal, Eric

    2001-04-01

    The authors present a resonant permittivity measurement method which works over a large microwave frequency domain, with a very small volume sample of dielectric material. The cell is a helical resonator having many modes of resonance. The shifts of resonance frequency and Q-factors are better interpreted with a bilinear function which depends on the complex permittivity of the material than by applying the classical perturbation formula. Results concerning two different catalysts which are used in the coupling oxidation methane reaction are given as a function of the temperature and the frequency to illustrate the correlation of both data sets and the differences in catalytic mechanisms.

  18. Rational design of inorganic dielectric materials with expected permittivity

    Science.gov (United States)

    Xie, Congwei; Oganov, Artem R.; Dong, Dong; Liu, Ning; Li, Duan; Debela, Tekalign Terfa

    2015-11-01

    Techniques for rapid design of dielectric materials with appropriate permittivity for many important technological applications are urgently needed. It is found that functional structure blocks (FSBs) are helpful in rational design of inorganic dielectrics with expected permittivity. To achieve this, coordination polyhedra are parameterized as FSBs and a simple empirical model to evaluate permittivity based on these FSB parameters is proposed. Using this model, a wide range of examples including ferroelectric, high/low permittivity materials are discussed, resulting in several candidate materials for experimental follow-up.

  19. Experimental Study on Core Permittivity of Xinjiang Oilfield

    Institute of Scientific and Technical Information of China (English)

    Ke Shizhen; Gao Jianying; Sun Yanru; Cai Minlong; Ma Runsheng

    2007-01-01

    This paper introduces the principles and procedures of the core permittivity measurement using a parallel capacitor with an electromagnetic shield. The cores from the Xinjiang oilfield were measured by using the frequency-swept method at different salinities and saturations. The effects of salinity, frequency, porosity and saturation on core pennittivity were investigated. The relationship of core permittivity versus water saturation and the relationship of dry core permittivity versus porosity were obtained. The permittivity values of rock matrix and oil were obtained at a frequency of 47 MHz and 200 MHz, and would provide guidance for the interpretation of dual frequency dielectric logging data.

  20. Using Semantic Wikis for Structured Argument in Medical Domain

    CERN Document Server

    Groza, Adrian

    2010-01-01

    This research applies ideas from argumentation theory in the context of semantic wikis, aiming to provide support for structured-large scale argumentation between human agents. The implemented prototype is exemplified by modelling the MMR vaccine controversy.

  1. Perception and Cognition Are Largely Independent, but Still Affect Each Other in Systematic Ways: Arguments from Evolution and the Consciousness-Attention Dissociation

    Science.gov (United States)

    Montemayor, Carlos; Haladjian, Harry H.

    2017-01-01

    The main thesis of this paper is that two prevailing theories about cognitive penetration are too extreme, namely, the view that cognitive penetration is pervasive and the view that there is a sharp and fundamental distinction between cognition and perception, which precludes any type of cognitive penetration. These opposite views have clear merits and empirical support. To eliminate this puzzling situation, we present an alternative theoretical approach that incorporates the merits of these views into a broader and more nuanced explanatory framework. A key argument we present in favor of this framework concerns the evolution of intentionality and perceptual capacities. An implication of this argument is that cases of cognitive penetration must have evolved more recently and that this is compatible with the cognitive impenetrability of early perceptual stages of processing information. A theoretical approach that explains why this should be the case is the consciousness and attention dissociation framework. The paper discusses why concepts, particularly issues concerning concept acquisition, play an important role in the interaction between perception and cognition. PMID:28174551

  2. Printed circuit board permittivity measurement using waveguide and resonator rings

    NARCIS (Netherlands)

    Op 't Land, Sjoerd; Tereshchenko, O.V.; Ramdani, Mohamed; Leferink, Frank Bernardus Johannes; Perdriau, Richard

    2014-01-01

    Knowing the frequency dependent complex permittivity of Printed Circuit Board (PCB) substrates is important in modern electronics. In this paper, two methods for measuring the permittivity are applied to the same Flame Resistant (FR4) substrate and the results are compared. The reference measurement

  3. Rethinking the Argumentative Essay

    Science.gov (United States)

    Schneer, David

    2014-01-01

    This article investigates the construction of the argumentative essay as it is commonly presented in academic writing textbooks and classrooms for English language learners. The author first examines the traditional three-stage structure (thesis-argument-conclusion) and then problematizes it within a genre-based approach to academic writing. He…

  4. Defining Rhetorical Argumentation

    DEFF Research Database (Denmark)

    Kock, Christian Erik J

    2013-01-01

    This article argues for a definition of rhetorical argumentation based on the theme of the argumentation, i.e., the issue in dispute - rather than its aim (e.g., to ‘win’) or its means (e.g., emotional appeals). The principal thinkers in the rhetorical tradition, from Aristotle onwards, saw...

  5. Arguments from parallel reasoning

    NARCIS (Netherlands)

    van Laar, Jan Albert; Ribeiro, H.J.

    2014-01-01

    Argumentation is a co-production by a proponent and an opponent who engage in a critical examination of their difference of opinion, aiming to resolve it on the merits of both sides, or so I assume in this paper. I shall investigate the consequences of this view for a particular type of argument fro

  6. Thermodynamical Arguments against Evolution

    Science.gov (United States)

    Rosenhouse, Jason

    2017-01-01

    The argument that the second law of thermodynamics contradicts the theory of evolution has recently been revived by anti-evolutionists. In its basic form, the argument asserts that whereas evolution implies that there has been an increase in biological complexity over time, the second law, a fundamental principle of physics, shows this to be…

  7. Rethinking the Argumentative Essay

    Science.gov (United States)

    Schneer, David

    2014-01-01

    This article investigates the construction of the argumentative essay as it is commonly presented in academic writing textbooks and classrooms for English language learners. The author first examines the traditional three-stage structure (thesis-argument-conclusion) and then problematizes it within a genre-based approach to academic writing. He…

  8. On Argument and Diagrams.

    Science.gov (United States)

    Kneupper, Charles W.

    1978-01-01

    Responds to Charles Willard's recommendations (in an article in "Communication Monographs," November 1976) that argument be viewed as an attempt to establish formal relationships among symbolic structures. Demonstrates flaws in this redefinition and shows argument diagrams to be theoretically and practically justifiable. (JMF)

  9. Defining Rhetorical Argumentation

    DEFF Research Database (Denmark)

    Kock, Christian Erik J

    2013-01-01

    rhetoric as practical reasoning, i.e., reasoning on proposals for action or choice, not on propositions that may be either true or false. Citing several contemporary philosophers, the article argues that such a definition acquits rhetorical argumentation of any culpable unconcern with truth and explains...... certain peculiar properties of it that tend to be under-theorized in argumentation theory....

  10. Arguments from parallel reasoning

    NARCIS (Netherlands)

    van Laar, Jan Albert; Ribeiro, H.J.

    2014-01-01

    Argumentation is a co-production by a proponent and an opponent who engage in a critical examination of their difference of opinion, aiming to resolve it on the merits of both sides, or so I assume in this paper. I shall investigate the consequences of this view for a particular type of argument

  11. Disregarding the 'Hole Argument'

    CERN Document Server

    Roberts, Bryan W

    2014-01-01

    Jim Weatherall has suggested that Einstein's hole argument, as presented by Earman and Norton (1987), is based on a misleading use of mathematics. I argue on the contrary that Weatherall demands an implausible restriction on how mathematics is used. The hole argument, on the other hand, is in no new danger at all.

  12. Improvements on effective permittivity measurements of powdered alumina: Implications for bulk permittivity properties of asteroid regoliths

    Science.gov (United States)

    Hickson, Dylan; Sotodeh, Shahroukh; Daly, Michael G.; Ghent, Rebecca; Nolan, Michael C.

    2017-01-01

    Accurate measurements of the dielectric properties of materials are essential in constraining interpretations of radar observations of planetary bodies. For bodies whose surfaces are comprised of regolith this requires an understanding of the behaviour of the bulk permittivity of powders. In this research we measure the effective permittivity of powdered aluminium oxide (or alumina, Al2O3) in a 7 mm and 14 mm (diameter) coaxial airline at 7.5 GHz for multiple samples with varying grain size. The dielectric constant of alumina is extracted from these measurements using the Bruggeman (Effective Medium Approximation) mixing equation. We develop a model to account for heterogeneity within the airline, specifically in regards to local variation in porosity. The results of the model show good correlation to experimental data and effectively correct for grain size effects on the measured bulk permittivity. We show that particle shape can have a significant impact on the output of the model and can be accounted for by modelling particles as ellipsoids rather than perfect spheres, where the depolarization factor must be measured and averaged for a specific sample batch.

  13. Guidelines for writing an argumentative essay

    OpenAIRE

    Aleksandra Egurnova

    2014-01-01

    The guidelines below are intended for teachers, professors, students, and the public at large who are interested in the issues of English writing culture. They provide a detailed plan for completing the writing task–writing an argumentative essay.

  14. Preliminary Broadband Measurements of Dielectric Permittivity of Planetary Regolith Analog Materials Using a Coaxial Airline

    Science.gov (United States)

    Boivin, A.; Tsai, C. A.; Ghent, R. R.; Daly, M. G.

    2014-12-01

    When considering radar observations of airless bodies containing regolith, the radar backscatter coefficient is dependent upon the complex dielectric permittivity of the regolith materials. In many current applications of imaging radar data, uncertainty in the dielectric permittivity precludes quantitative estimates of such important parameters as regolith thickness and depth to buried features (e.g., lava flows on the Aristarchus Plateau on the Moon and the flows that surround the Quetzalpetlatl Corona on Venus). For asteroids, radar is an important tool for detecting and characterizing regoliths. Many previous measurements of the real and/or complex parts of the dielectric permittivity have been made, particularly for the Moon (on both Apollo samples and regolith analogues). However, no studies to date have systematically explored the relationship between permittivity and the various mineralogical components such as presence of FeO and TiO2. For lunar materials, the presence of the mineral ilmenite (FeTiO3), which contains equal portions FeO and TiO2, is thought to be the dominant factor controlling the loss tangent (tanδ, the ratio of the imaginary and real components of the dielectric permittivity). Ilmenite, however, is not the only mineral to contain iron in the lunar soil and our understanding of the effect of iron on the loss tangent is insufficient. Beyond the Moon, little is known about the effects on permittivity of carbonaceous materials. This is particularly relevant for missions to asteroids, such as the OSIRIS-REx mission to (101955) Bennu, a carbonaceous asteroid whose regolith composition is largely unknown. Here we present preliminary broadband (300 Mhz to 14 GHz) measurements on materials intended as planetary regolith analogs. Our ultimate goal is to establish a database of the effects of a wide range mineralogical components on dielectric permittivity, in support of the OSIRIS REx mission and ongoing Earth-based radar investigation of the Moon

  15. Argumentation and discourse

    Directory of Open Access Journals (Sweden)

    José Luiz Fiorin

    2014-06-01

    Full Text Available After demonstrating that studies of argumentation, which spread throughout modern linguistics from Ducrot and Anscombre’s pragmatics, do not align with discourse studies because, for these authors, argumentation is a fact of langue and not a discursive fact, this textaims to show how discursive theories can work with the issue of argumentation. They cannot be restricted to linguistic microanalysis as adopted by integrated pragmatics, although eventually they can make use of it. They should revisit the classical tradition. If, on the one hand, the rhetoric studied the discursive construction of arguments and on the other studied the antiphonic dimension of discourses, the discursive theories should inherit from the rhetoric work; that is, they should read it in the light of the theoretical issues expressed today. To inherit from rhetoric work means, therefore, taking into account centuries of previous studies, to describe according to current discursive studies the discursive mechanisms which enable the speaker to produce meaning effects that make the audience believe what is said; it also means to analyze the actual operational mode of argumentation, i.e., the dialogism in argumentation.

  16. Arguments from Developmental Order.

    Science.gov (United States)

    Stöckle-Schobel, Richard

    2016-01-01

    In this article, I investigate a special type of argument regarding the role of development in theorizing about psychological processes and cognitive capacities. Among the issues that developmental psychologists study, discovering the ontogenetic trajectory of mechanisms or capacities underpinning our cognitive functions ranks highly. The order in which functions are developed or capacities are acquired is a matter of debate between competing psychological theories, and also philosophical conceptions of the mind - getting the role and the significance of the different steps in this order right could be seen as an important virtue of such theories. Thus, a special kind of strategy in arguments between competing philosophical or psychological theories is using developmental order in arguing for or against a given psychological claim. In this article, I will introduce an analysis of arguments from developmental order, which come in two general types: arguments emphasizing the importance of the early cognitive processes and arguments emphasizing the late cognitive processes. I will discuss their role in one of the central tools for evaluating scientific theories, namely in making inferences to the best explanation. I will argue that appeal to developmental order is, by itself, an insufficient criterion for theory choice and has to be part of an argument based on other core explanatory or empirical virtues. I will end by proposing a more concerted study of philosophical issues concerning (cognitive) development, and I will present some topics that also pertain to a full-fledged 'philosophy of development.'

  17. Application and electronic structure of high-permittivity dielectrics

    Energy Technology Data Exchange (ETDEWEB)

    Perevalov, Timofei V; Gritsenko, Vladimir A [Rzhanov Institute of Semiconductor Physics, Siberian Branch of the Russian Academy of Sciences, Novosibirsk (Russian Federation)

    2010-09-07

    Major applications of high-permittivity dielectric materials in silicon devices are reviewed. The basics and software implementations of the electron density functional method are considered. Results of first-principle calculations of the electronic structure are analyzed for the three most important and promising high-permittivity dielectrics, Al{sub 2}O{sub 3}, HfO{sub 2}, and TiO{sub 2}. (reviews of topical problems)

  18. Enhancing dielectric permittivity for energy-storage devices through tricritical phenomenon

    Science.gov (United States)

    Gao, Jinghui; Wang, Yan; Liu, Yongbin; Hu, Xinghao; Ke, Xiaoqin; Zhong, Lisheng; He, Yuting; Ren, Xiaobing

    2017-01-01

    Although dielectric energy-storing devices are frequently used in high voltage level, the fast growing on the portable and wearable electronics have been increasing the demand on the energy-storing devices at finite electric field strength. This paper proposes an approach on enhancing energy density under low electric field through compositionally inducing tricriticality in Ba(Ti,Sn)O3 ferroelectric material system with enlarged dielectric response. The optimal dielectric permittivity at tricritical point can reach to εr = 5.4 × 104, and the associated energy density goes to around 30 mJ/cm3 at the electric field of 10 kV/cm, which exceeds most of the selected ferroelectric materials at the same field strength. The microstructure nature for such a tricritical behavior shows polarization inhomogeneity in nanometeric scale, which indicates a large polarizability under external electric field. Further phenomenological Landau modeling suggests that large dielectric permittivity and energy density can be ascribed to the vanishing of energy barrier for polarization altering caused by tricriticality. Our results may shed light on developing energy-storing dielectrics with large permittivity and energy density at low electric field.

  19. The argument from transfer.

    Science.gov (United States)

    Munthe, Christian

    1996-01-01

    Utilitarian arguments on bioethical issues regarding human reproduction typically start with the view that it is wrong, other things being equal, not to procreate when this would have resulted in an additional being with a life worth living. The paper takes this view for granted and examines the common utilitarian claim that overpopulation and destitution in the world mean that, in practice, this obligation to procreate, other things being equal, often turns into a (categorical) obligation not to procreate. A version of this argument is defended -- a version called the argument from transfer -- according to which, rather than having additional children and care for them in order to make them happy, many people in the West ought to abstain from procreation and take care of destitute children already existing. The reasoning leading up to this conclusion raises some philosophical questions, seldom discussed in connection with bioethics, which indicate that the argument from transfer, although supporting the claim above, cannot neutralise the obligation to create more happy people as easily as assumed by utilitarians. It is argued that the argument from transfer may place many people facing the choice of procreation in a peculiar moral dilemma.

  20. Thermodynamical Arguments Against Evolution

    Science.gov (United States)

    Rosenhouse, Jason

    2017-02-01

    The argument that the second law of thermodynamics contradicts the theory of evolution has recently been revived by anti-evolutionists. In its basic form, the argument asserts that whereas evolution implies that there has been an increase in biological complexity over time, the second law, a fundamental principle of physics, shows this to be impossible. Scientists have responded primarily by noting that the second law does not rule out increases in complexity in open systems, and since the Earth receives energy from the Sun, it is an open system. This reply is correct as far as it goes, and it adequately rebuts the most crude versions of the second law argument. However, it is insufficient against more sophisticated versions, and it leaves many relevant aspects of thermodynamics unexplained. We shall consider the history of the argument, explain the nuances various anti-evolution writers have brought to it, and offer thorough explanations for why the argument is fallacious. We shall emphasize in particular that the second law is best viewed as a mathematical statement. Since anti-evolutionists never make use of the mathematical structure of thermodynamics, invocations of the second law never contribute anything substantive to their discourse.

  1. Reasoning Serves Argumentation in Children

    Science.gov (United States)

    Mercier, Hugo

    2011-01-01

    The argumentative theory of reasoning (Mercier & Sperber, in press) claims that reasoning evolved for argumentation: to find and evaluate arguments in dialogic contexts. The theory has drawn most of its supportive evidence from work with adults, leaving open the possibility that argumentive features of reasoning are in fact entirely learned.…

  2. Design and Implementation of an Induction Probe for Measuring Permittivity and Resistivity in Materials

    CERN Document Server

    Settimi, A; Baskaradas, J A; Bianchi, C

    2009-01-01

    In this paper, we propose a discussion concerning the design and implementation of an induction probe for electrical SPECTROscopy which performs simultaneous and not invasive measurements on the electrical RESistivity and dielectric PERmittivity of the terrestrial ground and concretes (SPECTRORESPER probe). In order to design a SPECTRORESPER which measures resistivity and permittivity with inaccuracies below a prefixed limit in a band of low frequencies, the probe should be connected to an appropriate analogical digital converter (ADC), which samples in uniform or in phase and quadrature (IQ) mode, otherwise to a lock-in amplifier. We develop a large number of numerical simulations, applying the Mathcad program, which provide the optimization of the height above ground, the electrode-electrode distance and working frequencies minimizing the inaccuracies of the SPECTRORESPER, in galvanic or capacitive contact with terrestrial soils or concretes, of low or high resistivity. As final findings, we underline that ...

  3. Ultra-low percolation threshold in ferrite-metal cofired ceramics brings both high permeability and high permittivity.

    Science.gov (United States)

    Wang, Liang; Bai, Yang; Lu, Xuefei; Cao, Jiang-Li; Qiao, Li-Jie

    2015-01-05

    High permeability and high permittivity are hard to be achieved simultaneously, either in single-phased materials or in composite materials, such as ferrite-ferroelectric ceramic composites and ferrite-metal percolative composites. In this work, ultra-low percolation threshold is achieved in NiZnCu ferrite-Ag cofired ceramics, which endows the composite with both high permeability and high permittivity by minimizing the negative effect of nonmagnetic conductive fillers on magnetic properties. The percolation threshold is controlled by the temperature matching between ferrite densification and Ag melting. A thin and long percolative net forms between large ferrite grains under a proper cofiring process, which brings a low percolation threshold of 1.21vol%, more than one order of magnitude lower than the theoretical value of 16vol%. Near the ultra-low threshold, the composite exhibits a high permeability of 585 and a high permittivity of 78.

  4. Anomalous Power Law Dispersions in ac Conductivity and Permittivity Shown to be Characteristics of Microstructural Electrical Networks

    Science.gov (United States)

    Almond, D. P.; Bowen, C. R.

    2004-04-01

    The frequency dependent ac conductivity and permittivity of porous lead zirconate titanate ceramic with the pore volume filled with water are shown to match the simulated electrical response of a large network of randomly positioned resistors and capacitors. Anomalous power law dispersions in conductivity and permittivity are shown to be an electrical response characteristic of the microstructural network formed by the porous lead zirconate titanate pore structure. The anomalous power law dispersions of a wide range of materials are also suggested to be microstructural network characteristics.

  5. The Language of Argumentation

    Science.gov (United States)

    Taylor, Laurie

    2013-01-01

    Using scientific debate focuses students on the real-life applications and implications of science and increases their reasoning skills, presentation skills, and science content knowledge. In this article, the author defines an "argument" as a position based on evidence and a "debate" as a formal setting in which two teams…

  6. Justification and Argumentation

    Directory of Open Access Journals (Sweden)

    Szymanek Krzysztof

    2014-03-01

    Full Text Available In her paper “Argumentation theory and the conception of epistemic justification”, Lilian Bermejo-Luque presents a critique of deductivism in argumentation theory, as well as her own concept of epistemic justification inspired by the views of Stephen Toulmin. Reading this paper induced me to reflect on the mutual relation between the notions of justification and argumentation. In this work I would like to first draw the reader’s attention to a few issues which seem debatable to me, or which I find worth presenting from a slightly different point of view than that of Lilian Bermejo-Luque. I agree that deductivism is not suitable for a general theory of evaluation of arguments although the critique of deductivism presented by the Author appears as not fully adequate to me. Then I proceed to presenting my doubts about the “conception of justification as a proper outcome of good argumentation” presented in the work. I need to emphasise that due to a broad range of topics addressed by me in this short paper, the description of some of them will be neither fully precise nor exhaustive.

  7. Framing for Scientific Argumentation

    Science.gov (United States)

    Berland, Leema K.; Hammer, David

    2012-01-01

    In recent years, research on students' scientific argumentation has progressed to a recognition of nascent resources: Students can and do argue when they experience the need and possibility of persuading others who may hold competing views. Our purpose in this article is to contribute to this progress by applying the perspective of framing to the…

  8. Measurement of relative permittivity of LTCC ceramic at different temperatures

    Science.gov (United States)

    Tan, Qiulin; Kang, Hao; Qin, Li; Xiong, Jijun; Zhou, Zhaoying; Zhang, Wendong; Luo, Tao; Xue, Chenyang; Liu, Jun

    2014-03-01

    Devices based on LTCC (low-temperature co-fired ceramic) technology are more widely applied in high temperature environments, and the temperature-dependent properties of the LTCC material play an important role in measurements of the characteristics of these devices at high temperature. In this paper, the temperature-dependence of the relative permittivity of DuPont 951 LTCC ceramic is studied from room temperature to 500 °C. An expression for relative permittivity is obtained, which relates the relative permittivity to the resonant frequency, inductance, parasitic capacitance and electrode capacitance of the LTCC sample. Of these properties, the electrode capacitance is the most strongly temperature-dependent. The LTCC sample resonant frequency, inductance and parasitic capacitance were measured (from room temperature to 500 °C) with a high temperature measurement system comprising a muffle furnace and network analyzer. We found that the resonant frequency reduced and the inductance and parasitic capacitance increased slightly as the temperature increases. The relative permittivity can be calculated from experimental frequency, inductance and parasitic capacitance measurements. Calculating results show that the relative permittivity of DuPont 951 LTCC ceramic ceramic increases to 8.21 from room temperature to 500 °C.

  9. Measurement of relative permittivity of LTCC ceramic at different temperatures

    Directory of Open Access Journals (Sweden)

    Qiulin Tan

    2014-02-01

    Full Text Available Devices based on LTCC (low-temperature co-fired ceramic technology are more widely applied in high temperature environments, and the temperature-dependent properties of the LTCC material play an important role in measurements of the characteristics of these devices at high temperature. In this paper, the temperature-dependence of the relative permittivity of DuPont 951 LTCC ceramic is studied from room temperature to 500 °C. An expression for relative permittivity is obtained, which relates the relative permittivity to the resonant frequency, inductance, parasitic capacitance and electrode capacitance of the LTCC sample. Of these properties, the electrode capacitance is the most strongly temperature-dependent. The LTCC sample resonant frequency, inductance and parasitic capacitance were measured (from room temperature to 500 °C with a high temperature measurement system comprising a muffle furnace and network analyzer. We found that the resonant frequency reduced and the inductance and parasitic capacitance increased slightly as the temperature increases. The relative permittivity can be calculated from experimental frequency, inductance and parasitic capacitance measurements. Calculating results show that the relative permittivity of DuPont 951 LTCC ceramic ceramic increases to 8.21 from room temperature to 500 °C.

  10. Planning Argumentative Texts

    CERN Document Server

    Huang, X

    1994-01-01

    This paper presents \\proverb\\, a text planner for argumentative texts. \\proverb\\'s main feature is that it combines global hierarchical planning and unplanned organization of text with respect to local derivation relations in a complementary way. The former splits the task of presenting a particular proof into subtasks of presenting subproofs. The latter simulates how the next intermediate conclusion to be presented is chosen under the guidance of the local focus.

  11. Hidden circuits and argumentation

    Science.gov (United States)

    Leinonen, Risto; Kesonen, Mikko H. P.; Hirvonen, Pekka E.

    2016-11-01

    Despite the relevance of DC circuits in everyday life and schools, they have been shown to cause numerous learning difficulties at various school levels. In the course of this article, we present a flexible method for teaching DC circuits at lower secondary level. The method is labelled as hidden circuits, and the essential idea underlying hidden circuits is in hiding the actual wiring of DC circuits, but to make their behaviour evident for pupils. Pupils are expected to find out the wiring of the circuit which should enhance their learning of DC circuits. We present two possible ways to utilise hidden circuits in a classroom. First, they can be used to test and enhance pupils’ conceptual understanding when pupils are expected to find out which one of the offered circuit diagram options corresponds to the actual circuit shown. This method aims to get pupils to evaluate the circuits holistically rather than locally, and as a part of that aim this method highlights any learning difficulties of pupils. Second, hidden circuits can be used to enhance pupils’ argumentation skills with the aid of argumentation sheet that illustrates the main elements of an argument. Based on the findings from our co-operating teachers and our own experiences, hidden circuits offer a flexible and motivating way to supplement teaching of DC circuits.

  12. Malaysian Students' Scientific Argumentation: Do groups perform better than individuals?

    Science.gov (United States)

    Heng, Lee Ling; Surif, Johari; Hau Seng, Cher

    2015-02-01

    The practices of argumentation have recently been upheld as an important need to develop students' understanding of scientific concepts. However, the present education system in Malaysia is still largely examination-based and teacher-oriented. Thus, this study aims to examine the mastery level of scientific argumentation and its scheme among Malaysian secondary-level science students. A total of 120 students were randomly assigned to answer a Scientific Argumentation Test (SAT), either individually or in a group. Based on the answers, two groups of students, one who have answered with valid scientific concepts and another who have answered with invalid concepts, were identified and interviewed. Quantitative analysis was performed on the SAT results to determine students' mastery of scientific argumentation, and their argumentation schemes were assessed using content analysis performed on the interview transcripts. The results showed that students were weak in the construction of scientific arguments with valid concepts. Moreover, most of the constructed arguments consisted of misconceptions. The results also showed that students who were involved in group argumentation tended to have a more complex argumentation scheme, compared to individual students. As a group, students were able to argue with more scientific elements and showed their understanding of macro and submicro concepts. Hence, science teachers need to emphasize on the construction of scientific argumentation in their teaching, especially at the macro, submicro, and symbolic levels of representations, to ensure students' understanding of the concepts. This will therefore enhance their mastery of scientific argumentation and improve their content knowledge.

  13. Democracy, Argument and the University.

    Science.gov (United States)

    Myerson, George

    1995-01-01

    Based on the idea that universities are places in which argument is an essential element, the standards that should apply to such argument are examined, drawing on the literature of communication, persuasion, and educational philosophy. A variety of perspectives are examined and critiqued, and it is concluded that regulation of argument is a…

  14. Social Media Argumentation Mining: The Quest for Deliberateness in Raucousness

    OpenAIRE

    Šnajder, Jan

    2016-01-01

    Argumentation mining from social media content has attracted increasing attention. The task is both challenging and rewarding. The informal nature of user-generated content makes the task dauntingly difficult. On the other hand, the insights that could be gained by a large-scale analysis of social media argumentation make it a very worthwhile task. In this position paper I discuss the motivation for social media argumentation mining, as well as the tasks and challenges involved.

  15. Permittivity disorder induced Anderson localization in magnetophotonic crystals

    Energy Technology Data Exchange (ETDEWEB)

    Abdi-Ghaleh, R., E-mail: r.abdi@bonabu.ac.ir [Department of Laser and Optical Engineering, University of Bonab, 5551761167 Bonab (Iran, Islamic Republic of); Namdar, A. [Faculty of Physics, University of Tabriz, 5166614766 Tabriz (Iran, Islamic Republic of)

    2016-11-15

    This theoretical study was carried out to investigate the permittivity disorder induced Anderson localization of light in one-dimensional magnetophotonic crystals. It was shown that the disorder create the resonant transmittance modes associated with enhanced Faraday rotations inside the photonic band gap. The average localization length of the right- and left-handed circular polarizations (RCP and LCP), the total transmittance together with the ensemble average of the RCP and LCP phases, and the Faraday rotation of the structure were also investigated. For this purpose, the off-diagonal elements of the permittivity tensor were varied for various wavelengths of incident light. The obtained results revealed the nonreciprocal property of circular eigen modes. This study can potentially open up a new aspect for utilizing the disorder magnetophotonic structures in nonreciprocal systems such as isolators and circulators. - Highlights: • We theoretically investigated the permittivity disorder induced Anderson localization of light in magnetophotonic crystals. • The disorder considered in the diagonal elements of the permittivity tensor of magneto-optical layers. • The disorder create the resonant transmittance modes associated with enhanced Faraday rotations in the photonic band gap. • The average localization length of the circular polarizations and the ensemble average of their phases were investigated. • The obtained results revealed the nonreciprocal property of circular eigen modes.

  16. Super soft silicone elastomers with high dielectric permittivity

    DEFF Research Database (Denmark)

    Madsen, Frederikke Bahrt; Yu, Liyun; Hvilsted, Søren;

    2015-01-01

    Dielectric elastomers (DEs) have many favourable properties. The obstacle of high driving voltages, however, limits the commercial viability of the technology at present. Driving voltage can be lowered by decreasing the Young’s modulus and increasing the dielectric permittivity of silicone elasto...

  17. Functional silicone copolymers and elastomers with high dielectric permittivity

    DEFF Research Database (Denmark)

    Madsen, Frederikke Bahrt; Daugaard, Anders Egede; Hvilsted, Søren

    . This was done trough the synthesis of new functionalizable siloxane copolymers [2] that allow for the attachment of high dielectric permittivity molecules through copper-catalyzed azide-alkyne 1,3-dipolar cycloaddition (CuAAC) reactions. The synthesised siloxane copolymers were prepared via the tris...

  18. Events, Arguments, and Aspects

    DEFF Research Database (Denmark)

    Robering, Klaus

    2014-01-01

    Verbs do often take arguments of quite different types. In an orthodox type-theoretic framework this results in an extreme polysemy of many verbs. In this article, it is shown that this unwanted consequence can be avoided when a theory of "abstract objects" is adopted according to which...... these objects represent non-objectual entities in contexts from which they are excluded by type restrictions. Thus these objects are "abstract'' in a functional rather than in an ontological sense: they function as representatives of other entities but they are otherwise quite normal objects. Three examples...

  19. Research Challenges for Argumentation

    OpenAIRE

    2008-01-01

    The first articles on argumentation in computer science appeared circa 20 years ago. Since then we have seen great advances, establishing a solid theoretical basis, a broad canvas of applications, and, most recently, some realistic implementations. The field has gone from infancy to maturity, and the initial questions that researchers posed— "how do we do this?", "what is it good for?" and "how do we implement it’?"—are mostly answered.

  20. Statistics As Principled Argument

    CERN Document Server

    Abelson, Robert P

    2012-01-01

    In this illuminating volume, Robert P. Abelson delves into the too-often dismissed problems of interpreting quantitative data and then presenting them in the context of a coherent story about one's research. Unlike too many books on statistics, this is a remarkably engaging read, filled with fascinating real-life (and real-research) examples rather than with recipes for analysis. It will be of true interest and lasting value to beginning graduate students and seasoned researchers alike. The focus of the book is that the purpose of statistics is to organize a useful argument from quantitative

  1. Guidelines for writing an argumentative essay

    Directory of Open Access Journals (Sweden)

    Aleksandra Egurnova

    2014-05-01

    Full Text Available The guidelines below are intended for teachers, professors, students, and the public at large who are interested in the issues of English writing culture. They provide a detailed plan for completing the writing task–writing an argumentative essay.

  2. A Robust Geometric Model for Argument Classification

    Science.gov (United States)

    Giannone, Cristina; Croce, Danilo; Basili, Roberto; de Cao, Diego

    Argument classification is the task of assigning semantic roles to syntactic structures in natural language sentences. Supervised learning techniques for frame semantics have been recently shown to benefit from rich sets of syntactic features. However argument classification is also highly dependent on the semantics of the involved lexicals. Empirical studies have shown that domain dependence of lexical information causes large performance drops in outside domain tests. In this paper a distributional approach is proposed to improve the robustness of the learning model against out-of-domain lexical phenomena.

  3. The Effects of Forensics Training on Verbal Aggression and Argumentativeness.

    Science.gov (United States)

    Colbert, Kent R.; Dorff, Todd

    A study focused on the effects of forensic participation on two specific traits--argumentativeness and verbal aggression. Two hundred eighty-one high school forensic students participating at a large western forensic tournament in the beginning of the 1990 academic year completed D. A. Infante's Argumentative and Verbal Aggression Scales. Results…

  4. Malaysian Students' Scientific Argumentation: Do Groups Perform Better than Individuals?

    Science.gov (United States)

    Heng, Lee Ling; Surif, Johari; Seng, Cher Hau

    2015-01-01

    The practices of argumentation have recently been upheld as an important need to develop students' understanding of scientific concepts. However, the present education system in Malaysia is still largely examination-based and teacher-oriented. Thus, this study aims to examine the mastery level of scientific argumentation and its scheme among…

  5. Permittivity and permeability of semi-infinite metamaterial

    Science.gov (United States)

    Porvatkina, O. V.; Tishchenko, A. A.; Strikhanov, M. N.

    2016-08-01

    In our work we investigate dielectric and magnetic properties of semi-infinite metamaterial consisting of particles of different possible nature: atoms, molecules, nanoparticles, etc. It is important that these particles would have magnetic properties. Polarization of a near-surface layer is known to differ from its bulk value for non-magnetic materials; for magnetic materials, including metamaterials, the situation should be similar, which is the subject of our research. We obtain analogues of the Clausius-Mossotti relation both for permittivity and permeability taking into account the local field effects in the longwave approximation for semi-infinite metamaterial. These relations describe the connection between macroscopic characteristics of the semi-infinite metamaterial (permittivity and permeability) and characteristics of constituent particles (dielectric polarizability and magnetic polarizability), which is a bright example of multi-scale approach - method very popular today in physical and computer simulating.

  6. Directional perfect absorption using deep subwavelength low permittivity films

    CERN Document Server

    Luk, Ting S; Kim, Iltai; Feng, Simin; Jun, Young Chul; Liu, Sheng; Wright, Jeremy B; Brener, Igal; Catrysse, Peter B; Fan, Shanhui; Sinclair, Michael B

    2014-01-01

    We experimentally demonstrate single beam directional perfect absorption (to within experimental accuracy) of p-polarized light in the near-infrared using unpatterned, deep subwavelength films of indium tin oxide (ITO) on Ag. The experimental perfect absorption occurs slightly above the epsilon-near-zero (ENZ) frequency of ITO where the permittivity is less than one. Remarkably, we obtain perfect absorption for films whose thickness is as low as ~1/50th of the operating free-space wavelength and whose single pass attenuation is only ~ 5%. We further derive simple analytical conditions for perfect absorption in the subwavelength-film regime that reveal the constraints that the ITO permittivity must satisfy if perfect absorption is to be achieved. Then, to get a physical insight on the perfect absorption properties, we analyze the eigenmodes of the layered structure by computing both the real-frequency/complex-wavenumber and the complex-frequency/real-wavenumber modal dispersion diagrams. These analyses allow u...

  7. Permittivity disorder induced Anderson localization in magnetophotonic crystals

    Science.gov (United States)

    Abdi-Ghaleh, R.; Namdar, A.

    2016-11-01

    This theoretical study was carried out to investigate the permittivity disorder induced Anderson localization of light in one-dimensional magnetophotonic crystals. It was shown that the disorder create the resonant transmittance modes associated with enhanced Faraday rotations inside the photonic band gap. The average localization length of the right- and left-handed circular polarizations (RCP and LCP), the total transmittance together with the ensemble average of the RCP and LCP phases, and the Faraday rotation of the structure were also investigated. For this purpose, the off-diagonal elements of the permittivity tensor were varied for various wavelengths of incident light. The obtained results revealed the nonreciprocal property of circular eigen modes. This study can potentially open up a new aspect for utilizing the disorder magnetophotonic structures in nonreciprocal systems such as isolators and circulators.

  8. Study of the magnetite to maghemite transition using microwave permittivity and permeability measurements.

    Science.gov (United States)

    Cuenca, Jerome Alexander; Bugler, Keith; Taylor, Stuart; Morgan, David; Williams, Paul; Bauer, Johann; Porch, Adrian

    2016-03-16

    The microwave cavity perturbation (MCP) technique is used to identify the transition from magnetite (Fe3O4) to the meta-stable form of maghemite (γ-Fe2O3). In this study Fe3O4 was annealed at temperatures from 60 to 300 °C to vary the oxidation. Subsequent to annealing, the complex permittivity and magnetic permeability of the iron oxide powders were measured. The transition to γ-Fe2O3 was corroborated with x-ray diffraction (XRD), x-ray photoelectron spectroscopy (XPS) and vibrating sample magnetometry (VSM). XRD, XPS and VSM implied that the starting powder was consistent with Fe3O4 and the powders annealed at more than 200 °C were transitioning to γ-Fe2O3. The MCP measurements gave large differences in both complex permittivity and magnetic permeability of the two phases in the frequency range of 2.5-10.2 GHz. Magnetic permeability decreased with annealing temperature, though magnetic losses showed frequency dependent behaviour. Complex permittivity measurements showed a large decrease in both dielectric constant and losses at all measurement frequencies, as well as a prominent loss peak centred around the phase transition temperatures. We interpret the loss peak as being a consequence of field effects due to an intermediate multi-phase mixture. Additionally, almost no frequency dependence was observed. The reduction in complex permittivity implies that the Feoct(2+) cations in the lattice provide a significant contribution to polarization at microwave frequencies and the effects of Feoct(3+) are nominal in comparison.. The change in loss can be explained as a combination of the differences in the effective conductivity of the two phases (i.e. Fe3O4 exhibits electron-hopping conduction whereas the presence of vacancies in γ-Fe2O3 nullifies this). This shows that the non-invasive MCP measurements serve as a highly sensitive and versatile method for looking at this phase transition in iron and potentially the effects of oxidation states on the polarization

  9. Explicit Argumentation Instruction to Facilitate Conceptual Understanding and Argumentation Skills

    Science.gov (United States)

    Cetin, Pinar Seda

    2014-01-01

    Background: Argumentation is accepted by many science educators as a major component of science education. Many studies have investigated students' conceptual understanding and their engagement in argumentative activities. However, studies conducted in the subject of chemistry are very rare. Purpose: The present study aimed to investigate the…

  10. Permittivity measurements up to 30 GHz using micromachined probe

    Science.gov (United States)

    Kim, Jung-Mu; Oh, Dong Hoon; Park, Jae-Hyoung; Cho, Jei-Won; Kwon, Youngwoo; Cheon, Changyul; Kim, Yong-Kweon

    2005-03-01

    We implemented a micromachined probe for the measurement of biological properties using MEMS technology, and experimentally showed the suitability of the micromachined probe in biological applications. The micromachined probe was fabricated on a silicon substrate, and to remove wave transmission through the silicon substrate, we etched the silicon substrate from beneath a lower ground and made the etched silicon surface conducting by using thermal evaporation of Cr/Au and a coating of conductive epoxy. The micromachined probe consists of a CPW and strip line between benzo cyclo butene (BCB) layers, which is known to be a material with high resistivity, low loss tangent, and low permittivity at high frequency. We measured the permittivity of a number of well-known liquids—0.5%, 0.9% and 1.3% saline, acetone, ethanol, and muscle and fat of pork—as biological samples using the micromachined probe after liquid calibration. The measured permittivity of 0.9% saline agreed well with the expected value of the Cole-Cole equation. In this paper, we first demonstrate that the micromachined probe can provide broadband measurement of measurable solid materials, such as biological samples, and also of well-known liquids at microwave frequencies. The size of the micromachined probe is 2000 µm (width) × 580 µm (thickness) × 30 000 µm (length), and the aperture size of the micromachined probe is only 650 µm × 70 µm. Therefore, we can extract the biological information from very small biological tissues and reduce radiation effects. Thus we show the feasibility of low-cost, small and portable permittivity measurement systems using a micromachined open-ended coaxial RF MEMS probe.

  11. Explicit argumentation instruction to facilitate conceptual understanding and argumentation skills

    Science.gov (United States)

    Seda Cetin, Pinar

    2014-01-01

    Background: Argumentation is accepted by many science educators as a major component of science education. Many studies have investigated students' conceptual understanding and their engagement in argumentative activities. However, studies conducted in the subject of chemistry are very rare. Purpose: The present study aimed to investigate the effects of argumentation-based chemistry lessons on pre-service science teachers' understanding of reaction rate concepts, their quality of argumentation, and their consideration of specific reaction rate concepts in constructing an argument. Moreover, students' perceptions of argumentation lessons were explored. Sample: There were 116 participants (21 male and 95 female), who were pre-service first-grade science teachers from a public university. The participants were recruited from the two intact classes of a General Chemistry II course, both of which were taught by the same instructor. Design and methods: In the present study, non-equivalent control group design was used as a part of quasi-experimental design. The experimental group was taught using explicit argumentation activities, and the control group was instructed using traditional instruction. The data were collected using a reaction rate concept test, a pre-service teachers' survey, and the participants' perceptions of the argumentation lessons questionnaire. For the data analysis, the Wilcoxon Signed Rank Test, the Mann-Whitney U-test and qualitative techniques were used. Results: The results of the study indicated that an argumentation-based intervention caused significantly better acquisition of scientific reaction rate-related concepts and positively impacted the structure and complexity of pre-service teachers' argumentation. Moreover, the majority of the participants reported positive feelings toward argumentation activities. Conclusions: As students are encouraged to state and support their view in the chemistry classroom when studying reaction rate, it was

  12. Local dielectric permittivity profiles of sapphire/polypropylene interfaces

    Science.gov (United States)

    Yu, Liping; Ranjan, V.; Buongiorno Nardelli, M.; Bernholc, J.

    2009-03-01

    Recently, the need for high-power-density capacitors has stimulated research to develop composite dielectric materials with high-k nanoparticles embedded in a polymer matrix. In these materials, surfaces and interfaces may play an important role in determining the overall dielectric properties. We present first-principles investigations of the dielectric permittivity profiles across slabs and interfaces of sapphire(α-Al2O3)/isotactic-polypropylene(iPP). Our results indicate that the permittivity profile at interface strongly depends on the nanoscale averaging procedure. We propose an averaging model that ensures near-locality of the dielectric function. We find that: (i) the dielectric permittivity approaches the corresponding bulk value just a few atomic layers away from the interface or surface; (ii) the dielectric constant is enhanced at the surfaces of the isolated α-Al2O3 slabs, while no enhancement is observed at the iPP slab surfaces; and (iii) the dielectric transition at the αAl2O3/iPP is mainly confined in the αAl2O3 side.

  13. Een Scotistisch argument voor dualisme

    NARCIS (Netherlands)

    Ridder, de G.J.; Woudenberg, van R.

    2010-01-01

    In his recent book Waar geest is, is vrijheid [Where there is mind, there is freedom], Guus Labooy sets forth an original and intriguing argument, inspired by the work of John Duns Scotus, for substance dualism in the philosophy of mind. In this paper we argue that his argument, although worthy of s

  14. Disentangling The Thick Concept Argument

    DEFF Research Database (Denmark)

    Blomberg, Olle

    2007-01-01

    Critics argue that non-cognitivism cannot adequately account for the existence and nature of some thick moral concepts. They use the existence of thick concepts as a lever in an argument against non-cognitivism, here called the Thick Concept Argument (TCA). While TCA is frequently invoked...

  15. Incorporating Argumentation through Forensic Science

    Science.gov (United States)

    Wheeler, Lindsay B.; Maeng, Jennifer L.; Smetana, Lara K.

    2014-01-01

    This article outlines how to incorporate argumentation into a forensic science unit using a mock trial. Practical details of the mock trial include: (1) a method of scaffolding students' development of their argument for the trial, (2) a clearly outlined set of expectations for students during the planning and implementation of the mock…

  16. Disentangling The Thick Concept Argument

    DEFF Research Database (Denmark)

    Blomberg, Olle

    2007-01-01

    Critics argue that non-cognitivism cannot adequately account for the existence and nature of some thick moral concepts. They use the existence of thick concepts as a lever in an argument against non-cognitivism, here called the Thick Concept Argument (TCA). While TCA is frequently invoked...

  17. Collaborative argumentation in academic education

    NARCIS (Netherlands)

    Veerman, A.; Andriessen, J.; Kanselaar, G.

    2002-01-01

    The general purpose of this research is to discover principles for the design of educational tasks that provoke collaborative argumentation. The specific research question concentrates on the relationship between question asking and argumentation and is examined in three different collaborative lear

  18. Incorporating Argumentation through Forensic Science

    Science.gov (United States)

    Wheeler, Lindsay B.; Maeng, Jennifer L.; Smetana, Lara K.

    2014-01-01

    This article outlines how to incorporate argumentation into a forensic science unit using a mock trial. Practical details of the mock trial include: (1) a method of scaffolding students' development of their argument for the trial, (2) a clearly outlined set of expectations for students during the planning and implementation of the mock…

  19. Assessing and Supporting Argumentation with Online Rubrics

    Science.gov (United States)

    Lu, Jingyan; Zhang, Zhidong

    2013-01-01

    Writing and assessing arguments are important skills and there is evidence that using rubrics to assess the arguments of others can help students write better arguments. Thus, this study investigated whether students were able to write better arguments after using rubrics to assess the written arguments by peers. Students in 4 secondary 4 classes…

  20. Optimal requirements of a data acquisition system for a quadrupolar probe used in resistivity and permittivity surveys

    Directory of Open Access Journals (Sweden)

    Cesidio Bianchi

    2010-12-01

    Full Text Available This report discusses the development and engineering of a suitable quadrupolar probe for simultaneous and noninvasive surveys of electrical resistivity and dielectric permittivity. The quadrupolar probe can perform measurements on a subsurface with inaccuracies below a fixed limit (10% in a bandwidth of low frequency (100 kHz. The quadrupole should be connected to an appropriate analog–digital converter that samples in phase and quadrature (IQ or in uniform mode. If the probe is characterized by a galvanic contact with the surface, the inaccuracies in the measurements of resistivity and permittivity due to the IQ or uniform sampling analog–digital converter are analytically expressed. A large number of numerical simulations show that the performances of the probe depend on the selected sampler, and that the IQ is better compared to the uniform mode under the same operating conditions, i.e. for bit resolution and medium.

  1. Argument z celowości (The argument from design

    Directory of Open Access Journals (Sweden)

    Richard Swinburne

    2012-06-01

    Full Text Available Author argues that there are no formal fallacies in the argument from design, if the argument is articulated with suffi cient care. According to modern science, he distinguishes two types of order or harmony in the world: regularities of co-presence and regularities of succession. He goes on to claim that Hume’s criticism directed against the argument from design, presented in Dialogues Concerning Natural Religion, used as its premises regularities of co-presence other than those produced by men, and did not appeal to the operation of regularities of succession. But a more developed science than Hume knew, more often appeals to the analogy of the order between the regularities of succession produced by human agents and those produced by the operation of natural laws. How strong this analogy is depends on whether the conclusion of the argument from design is true.

  2. Argument, Argumentation and Critical Thinking in Academic Writing

    Institute of Scientific and Technical Information of China (English)

    夏君君

    2013-01-01

    Academic writing has been emphasized for years among English major students, and PhD students who need to pub-lish their work in English, but few of these people could produce essays academically. The key problem that they are faced with is argument, argumentation and critical thinking in academic writing. These three notions are reviewed and the followed teaching preliminary suggestions are presented in this essay.

  3. Understanding the small object argument

    CERN Document Server

    Garner, Richard

    2007-01-01

    The small object argument is a transfinite construction which, starting from a set of maps in a category, generates a weak factorisation system on that category. As useful as it is, the small object argument has some problematic aspects: it possesses no universal property; it does not converge; and it does not seem to be related to other transfinite constructions occurring in categorical algebra. In this paper, we give an ``algebraic'' refinement of the small object argument, cast in terms of Grandis and Tholen's natural weak factorisation systems, which rectifies each of these three deficiencies.

  4. Free charge localization and effective dielectric permittivity in oxides

    Science.gov (United States)

    Maglione, Mario

    2016-06-01

    This review will deal with several types of free charge localization in oxides and their consequences on the effective dielectric spectra of such materials. The first one is the polaronic localization at the unit cell scale on residual impurities in ferroelectric networks. The second one is the collective localization of free charge at macroscopic interfaces like surfaces, electrodes and grain boundaries in ceramics. Polarons have been observed in many oxide perovskites mostly when cations having several stable electronic configurations are present. In manganites, the density of such polarons is so high as to drive a net lattice of interacting polarons. On the other hand, in ferroelectric materials like BaTiO3 and LiNbO3, the density of polarons is usually very small but they can influence strongly the macroscopic conductivity. The contribution of such polarons to the dielectric spectra of ferroelectric materials is described. Even residual impurities as for example Iron can induce well-defined anomalies at very low temperatures. This is mostly resulting from the interaction between localized polarons and the highly polarizable ferroelectric network in which they are embedded. The case of such residual polarons in SrTiO3 will be described in more detail, emphasizing the quantum polaron state at liquid helium temperatures. Recently, several nonferroelectric oxides have been shown to display giant effective dielectric permittivity. It is first shown that the frequency/temperature behavior of such parameters is very similar in very different compounds (donor-doped BaTiO3, CaCu3Ti4O12, LuFe2O4, Li-doped NiO, etc.). This similarity calls for a common origin of the giant dielectric permittivity in these compounds. A space charge localization at macroscopic interfaces can be the key for such extremely high dielectric permittivity.

  5. The thickness dependence of dielectric permittivity in thin films

    Science.gov (United States)

    Starkov, Ivan A.; Starkov, Alexander S.

    2016-08-01

    It is well known that the physical properties of thin films depend on their thickness. For a description of such dependences, it is proposed to use a classical model taking into account the presence of film interfaces. A dielectric ball near the half-space was chosen to adopt the approach. The dependence of the effective permittivity of the ball on geometrical and physical parameters of the system is analyzed. It is demonstrated that the dielectric constant of a film can be presented as a sum of the constant of a bulk material and the interface term.

  6. iQ Cavity for Material Permittivity Characterization

    CERN Document Server

    Allen, Kenneth W

    2016-01-01

    We present an X-band waveguide (WR90) and UHF waveguide (WR1500) measurement method that permits the extraction of the complex permittivity for low dielectric loss tangent material specimen. The extraction method relies on computational electromagnetic (CEM) simulations; coupled with a genetic algorithm; to fit the experimental measurement and the simulated transmitted scattering parameter (S21) of the TE10 mode through the waveguide with the material specimen partially filling the cross-section. This technique provides the material measurement community with the ability to accurately extract material properties of low-loss material specimen.

  7. Wireless power transfer based on dielectric resonators with colossal permittivity

    Science.gov (United States)

    Song, Mingzhao; Belov, Pavel; Kapitanova, Polina

    2016-11-01

    Magnetic resonant wireless power transfer system based on dielectric disk resonators made of colossal permittivity (ɛ = 1000) and low loss (tan δ = 2.5 × 10-4) microwave ceramic is experimentally investigated. The system operates at the magnetic dipole mode excited in the resonators providing maximal power transfer efficiency of 90% at the frequency 232 MHz. By applying an impedance matching technique, the efficiency of 50% is achieved within the separation between the resonators d = 16 cm (3.8 radii of the resonator). The separation, misalignment and rotation dependencies of wireless power transfer efficiency are experimentally studied.

  8. Self-Healing, High-Permittivity Silicone Dielectric Elastomer

    DEFF Research Database (Denmark)

    Madsen, Frederikke Bahrt; Yu, Liyun; Skov, Anne Ladegaard

    2016-01-01

    or cuts made directly to the material due to the reassembly of the ionic bonds that are broken during damage. The dielectric elastomers presented in this paper pave the way to increased lifetimes and the ability of dielectric elastomers to survive millions of cycles in high-voltage conditions....... possesses high dielectric permittivity and consists of an interpenetrating polymer network of silicone elastomer and ionic silicone species that are cross-linked through proton exchange between amines and acids. The ionically cross-linked silicone provides self-healing properties after electrical breakdown...

  9. Craig and Kalam Cosmological Argument

    Directory of Open Access Journals (Sweden)

    Gholamhosein Tavacoly

    2011-09-01

    Full Text Available   Among different arguments for the existence of God the Kalam cosmological argument is a very famous one which is elaborated by Professor William lane Craig. Craig claims that the universe began to exist , then he continues to say: everything that begins to exist has a cause and therefore the universe has a cause. But how do we know that the universe began to exist? This premise forms the most important part of Craig’s contention, and he bolsters it by four arguments, the first two are driven from philosophy and the other two, which he prefers to name them “confirmations from sciences” are driven from sciences the first one evokes to big bang theory and the seconds to the second principle of thermodynamic which are respectively adopted from cosmology and physics.   In this essay we are going to survey Craig’s arguments and estimate their value and weight.

  10. Craig and Kalam Cosmological Argument

    Directory of Open Access Journals (Sweden)

    Tavacoli, Gh

    2011-01-01

    Full Text Available Among different arguments for the existence of God the Kalam cosmological argument is a very famous one which is elaborated by Professor William lane Craig. Craig claims that the universe began to exist, then he continues to say: everything that begins to exist has a cause and therefore the universe has a cause. But how do we know that the universe began to exist? This premise forms the most important part of Craig’s contention, and he bolsters it by four arguments, the first two are driven from philosophy and the other two, which he prefers to name them “confirmations from sciences” are driven from sciences; the first one evokes to big bang theory and the seconds to the second principle of thermodynamic which are respectively adopted from cosmology and physics.In this essay we are going to survey Craig’s arguments and estimate their value and weight.

  11. Craig and Kalam Cosmological Argument

    Directory of Open Access Journals (Sweden)

    Gholamhosein Tavacoly

    2011-08-01

    Full Text Available Among different arguments for the existence of God the Kalam cosmological argument is a very famous one which is elaborated by Professor William lane Craig. Craig claims that the universe began to exist , then he continues to say: everything that begins to exist has a cause and therefore the universe has a cause. But how do we know that the universe began to exist? This premise forms the most important part of Craig’s contention, and he bolsters it by four arguments, the first two are driven from philosophy and the other two, which he prefers to name them “confirmations from sciences” are driven from sciences the first one evokes to big bang theory and the seconds to the second principle of thermodynamic which are respectively adopted from cosmology and physics.   In this essay we are going to survey Craig’s arguments and estimate their value and weight.

  12. Efficient computation of argumentation semantics

    CERN Document Server

    Liao, Beishui

    2013-01-01

    Efficient Computation of Argumentation Semantics addresses argumentation semantics and systems, introducing readers to cutting-edge decomposition methods that drive increasingly efficient logic computation in AI and intelligent systems. Such complex and distributed systems are increasingly used in the automation and transportation systems field, and particularly autonomous systems, as well as more generic intelligent computation research. The Series in Intelligent Systems publishes titles that cover state-of-the-art knowledge and the latest advances in research and development in intelligen

  13. Complex permittivity of composites based on dielectric matrices with carbon nanotubes

    Science.gov (United States)

    Usanov, D. A.; Skripal', A. V.; Romanov, A. V.

    2011-01-01

    The transmission spectra of microwave electromagnetic radiation interacting with a sample are used to determine the complex permittivity of a composite material based on a two-component epoxy adhesive having a certain volume fraction of inclusions in the form of multilayer carbon nanotubes or fine graphite particles. An inverse problem is solved for the dependence of the complex permittivity of the composite material on the volume fraction of carbon nanotubes, and their permittivity and average bulk electrical conductivity are determined.

  14. Microscopic dielectric permittivities of graphene nanoribbons and graphene

    Science.gov (United States)

    Fang, Jingtian; Vandenberghe, William G.; Fischetti, Massimo V.

    2016-07-01

    We derive a microscopic Poisson equation using the density-density response function. This equation is valid for any realistic potential perturbation and permits the study of dielectric response in nanostructures, especially in one-dimensional nanostructures and quantum dots. We apply this equation to simulate a nanoscale parallel-plate capacitor (nanocapacitor) with graphene as dielectric and two nanocapacitors with a graphene nanoribbon (GNR) as dielectric. The density-density response function is calculated using first-order perturbation theory and empirical pseudopotentials. From the microscopic electric field of the graphene nanocapacitor, we calculate the out-of-plane microscopic dielectric constant of graphene and from the electric field of GNR nanocapacitors, we calculate the full microscopic dielectric tensor of several GNRs with different widths. We find that the out-of-plane microscopic dielectric constants of GNRs and graphene do not depend on their energy band gap. We also study the effect of a surrounding dielectric on the dielectric permittivity of graphene and we conclude that the surrounding dielectric barely affects the dielectric permittivity of graphene.

  15. The Effective Permittivity of Dielectric-Particle Distributions

    Science.gov (United States)

    Tortora, Paul; Ceccio, Steven; Schultz, William; Torczynski, John; O'Hern, Timothy; Trujillo, Steven

    2003-11-01

    Electrical techniques to measure the material distribution in a multiphase flow use expressions that relate the electrical properties to the phase volume fractions. In this work, the Maxwell-Hewitt and other constitutive relations are assessed experimentally and computationally for distributions of dielectric spherical particles in a dielectric medium. The experiments use a gas-solid riser: distributions of interest include a packed bed (for calibration) and a dilute-core/dense-annulus distribution (typical of riser operation). Two wall-mounted electrodes measure the average permittivity in a cross section. The constitutive relations convert these values into solid volume fractions for comparison to independent gamma-densitometry-tomography measurements. Similarly, the code FIDAP is used to determine the average permittivity for various particle distributions. These results will ultimately be applied in a multiple-electrode electrical-impedance tomography system. This research is supported by the NSF GOALI program and Multiphase Fluid Dynamics Research Consortium funded by the DOE. Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the US Department of Energy under Contract DE-AC04-94AL85000.

  16. Ultra-broad-band electrical spectroscopy of soils and sediments—a combined permittivity and conductivity model

    Science.gov (United States)

    Loewer, M.; Günther, T.; Igel, J.; Kruschwitz, S.; Martin, T.; Wagner, N.

    2017-09-01

    We combined two completely different methods measuring the frequency-dependent electrical properties of moist porous materials in order to receive an extraordinary large frequency spectrum. In the low-frequency (LF) range, complex electrical resistivity between 1 mHz and 45 kHz was measured for three different soils and sandstone, using the spectral induced polarization (SIP) method with a four electrode cell. In the high-frequency (HF) radio to microwave range, complex dielectric permittivity was measured between 1 MHz and 10 GHz for the same samples using dielectric spectroscopy by means of the coaxial transmission line technique. The combined data sets cover 13 orders of magnitude and were transferred into their equivalent expressions: the complex effective dielectric permittivity and the complex effective electrical conductivity. We applied the Kramers-Kronig relation in order to justify the validity of the data combination. A new phenomenological model that consists of both dielectric permittivity and electrical conductivity terms in a Debye- and Cole-Cole-type manner was fitted to the spectra. The combined permittivity and conductivity model accounts for the most common representations of the physical quantities with respect to the individual measuring method. A maximum number of four relaxation processes was identified in the analysed frequency range. Among these are the free water and different interfacial relaxation processes, the Maxwell-Wagner effect, the counterion relaxation in the electrical double layer and the direct-current electrical conductivity. There is evidence that free water relaxation does not affect the electrical response in the SIP range. Moreover, direct current conductivity contribution (bulk and interface) dominates the losses in the HF range. Interfacial relaxation processes with relaxations in the HF range are broadly distributed down to the LF range. The slowest observed process in the LF range has a minor contribution to the HF

  17. The deconstruction of safety arguments through adversarial counter-argument

    Energy Technology Data Exchange (ETDEWEB)

    Armstrong, James M. [BAE Systems Systems Engineering Innovation Centre (SEIC), University of Loughborough (United Kingdom)]. E-mail: J.M.Armstrong@lboro.ac.uk; Paynter, Stephen E. [MBDA UK Ltd, Filton, Bristol (United Kingdom)]. E-mail: stephen.paynter@mbda.co.uk

    2007-11-15

    The project Deconstructive Evaluation of Risk In Dependability Arguments and Safety Cases (DERIDASC) has recently experimented with techniques borrowed from literary theory as safety case analysis techniques [Armstrong. Danger: Derrida at work. Interdiscipl Sci Rev 2003;28(2):83-94. ; Armstrong J, Paynter S. Safe systems: construction, destruction, and deconstruction. In: Redmill F, Anderson T, editors. Proceedings of the 11th safety critical systems symposium, Bristol, UK. Berlin: Springer; 2003. p. 62-76. ISBN:1-85233-696-X. ]. This paper introduces our high-level framework for 'deconstructing' safety arguments. Our approach is quite general and should be applicable to different types of safety argumentation framework. As one example, we outline how the approach would work in the context of the Goal Structure Notation (GSN)

  18. From connectives to argumentative markers: a quest for markers of argumentative moves and of related aspects of argumentative discourse

    NARCIS (Netherlands)

    A. Tseronis

    2011-01-01

    In this paper, I explore the potential of systematically studying the linguistic surface of discourse for the purposes of identifying markers of argumentative moves and other related categories, such as types of arguments and argumentative strategies. Such a list of argumentative markers can prove u

  19. Dielectric Properties of Tungsten Copper Barium Ceramic as Promising Colossal-Permittivity Material

    Science.gov (United States)

    Wang, Juanjuan; Chao, Xiaolian; Li, Guangzhao; Feng, Lajun; Zhao, Kang; Ning, Tiantian

    2017-08-01

    Ba(Cu0.5W0.5)O3 (BCW) ceramic has been fabricated and its dielectric properties investigated for use in energy-storage applications, revealing a very large dielectric constant (˜104) at 1 kHz. Moreover, the colossal-permittivity BCW ceramic exhibited fine microstructure and optimal temperature stability over a wide temperature range from room temperature to 500°C. The internal barrier layer capacitor mechanism was considered to be responsible for its high dielectric properties. Based on activation values, it is concluded that doubly ionized oxygen vacancies make a substantial contribution to the conduction and relaxation behaviors at grain boundaries. This study suggests that this kind of material has potential for use in high-density energy storage applications.

  20. Synthesis of Photoswitchable Magnetic Au–Fullerosome Hybrid Nanomaterials for Permittivity Enhancement Applications

    Directory of Open Access Journals (Sweden)

    Min Wang

    2015-08-01

    Full Text Available We designed and synthesized several nanomaterials 3 of three-layered core-shell (γ-FeOx@AuNP@[C60(>DPAF-C91or2]n nanoparticles (NPs. These NPs having e−-polarizable fullerosome structures located at the outer layer were fabricated from highly magnetic core-shell γ-FeOx@AuNPs. Fullerosomic polarization of 3 was found to be capable of causing a large amplification of material permittivity that is also associated with the photoswitching effect in the frequency range of 0.5‒4.0 GHz. Multilayered synthetic construction allows Förster resonance energy transfer (FRET of photoinduced accumulative surface plasmon resonance (SPR energy in the gold layer to the partially bilayered C60(>DPAF-C91or2-derived fullerosome membrane shell layer in a near-field of direct contact without producing radiation heat, which is commonly associated with SPR.

  1. Complex permittivity measurements and mixing laws of ceramic materials and application to microwave processing

    Science.gov (United States)

    Gershon, David Louis

    The complex permittivity of alumina composites was examined with respect to its dependence on the volume fraction of constituents, microstructure, processing temperature, and processing method. In addition, the effective permittivity of these composites was quantitatively modeled based on the permittivities, volume fractions, and microstructures of the constituents. The studies focused on the complex permittivity of alumina composites, which contained the lossy additives silicon carbide and copper oxide. Two composite systems were prepared by physically mixing alumina and one of the additives. A third composite system was produced by chemically precipitating copper oxide onto alumina. The two synthesis methods produced composites with different microstructures and complex permittivities. The imaginary part of the complex permittivity was generally larger in the chemically precipitated composites than in the physically mixed composites. The dependence of the complex permittivities of the composites on volume fraction and microstructure were compared with several algebraic mixing laws and with three dimensional, electrostatic numerical simulations. The algebraic mixing laws do not take into account for the dependence of the imaginary part of the complex permittivity on absorbed water and microstructure, which is affected by composite synthesis. By incorporating general physical characteristics of the composites, the electrostatic simulations were able to accurately predict their permittivity. Heating some selected alumina composites in conventional and microwave furnaces demonstrate several interesting results. The densification and dielectric proper-ties of the alumina/copper oxide composites varied due to processing temperature. The changes in these properties depended upon preparation method and not on heating method. The density and real part of the complex permittivity of alumina/silicon carbide also varied due to processing temperature and not on heating method

  2. A critical review of PASBio's argument structures for biomedical verbs

    Directory of Open Access Journals (Sweden)

    Cohen K Bretonnel

    2006-11-01

    Full Text Available Abstract Background Propositional representations of biomedical knowledge are a critical component of most aspects of semantic mining in biomedicine. However, the proper set of propositions has yet to be determined. Recently, the PASBio project proposed a set of propositions and argument structures for biomedical verbs. This initial set of representations presents an opportunity for evaluating the suitability of predicate-argument structures as a scheme for representing verbal semantics in the biomedical domain. Here, we quantitatively evaluate several dimensions of the initial PASBio propositional structure repository. Results We propose a number of metrics and heuristics related to arity, role labelling, argument realization, and corpus coverage for evaluating large-scale predicate-argument structure proposals. We evaluate the metrics and heuristics by applying them to PASBio 1.0. Conclusion PASBio demonstrates the suitability of predicate-argument structures for representing aspects of the semantics of biomedical verbs. Metrics related to theta-criterion violations and to the distribution of arguments are able to detect flaws in semantic representations, given a set of predicate-argument structures and a relatively small corpus annotated with them.

  3. Argumentation as an Interactional Process in Conversation.

    Science.gov (United States)

    Liddicoat, Anthony

    1995-01-01

    Analyzes argumentation and the ways in which idealized models of argumentation relate to the linguistic behavior of participants in argument as talk. Sequencing patterns of arguments are interactionally accomplished. Speakers produce turns which are related to their purpose in talking and that include speech act complexes appropriate for the…

  4. The Possibility and Actuality of Visual Arguments.

    Science.gov (United States)

    Blair, J. Anthony

    1996-01-01

    Analyzes visual argument as propositional argument in which the propositions and their argumentative functions are expressed visually, not verbally. Classifies visual argument as but one type of visual persuasion, which is but one type of visual communication, and a form of persuasion and rhetoric. Discusses advantages/disadvantages of visual…

  5. Peter Singer's argument for utilitarianism.

    Science.gov (United States)

    Buckle, Stephen

    2005-01-01

    The paper begins by situating Singer within the British meta-ethical tradition. It sets out the main steps in his argument for utilitarianism as the 'default setting' of ethical thought. It argues that Singer's argument depends on a hierarchy of reasons, such that the ethical viewpoint is understood to be an adaptation--an extension--of a fundamental self-interest. It concludes that the argument fails because it is impossible to get from this starting-point in self-interest to his conception of the ethical point of view. The fundamental problem is its mixing the immiscible: the Humean subordination of reason to interest with the Kantian conception of reason as universal and authoritative.

  6. Flexible nanodielectric materials with high permittivity for power energy storage.

    Science.gov (United States)

    Dang, Zhi-Min; Yuan, Jin-Kai; Yao, Sheng-Hong; Liao, Rui-Jin

    2013-11-26

    Study of flexible nanodielectric materials (FNDMs) with high permittivity is one of the most active academic research areas in advanced functional materials. FNDMs with excellent dielectric properties are demonstrated to show great promise as energy-storage dielectric layers in high-performance capacitors. These materials, in common, consist of nanoscale particles dispersed into a flexible polymer matrix so that both the physical/chemical characteristics of the nanoparticles and the interaction between the nanoparticles and the polymers have crucial effects on the microstructures and final properties. This review first outlines the crucial issues in the nanodielectric field and then focuses on recent remarkable research developments in the fabrication of FNDMs with special constitutents, molecular structures, and microstructures. Possible reasons for several persistent issues are analyzed and the general strategies to realize FNDMs with excellent integral properties are summarized. The review further highlights some exciting examples of these FNDMs for power-energy-storage applications.

  7. Simultaneous negative permittivity and permeability in a coherent atomic vapour

    Institute of Scientific and Technical Information of China (English)

    Shen Jian-Qi

    2007-01-01

    A new quantum optical mechanism to realize simultaneously negative electric permittivity and magnetic permeability is suggested. In order to obtain a negative permeability, we choose a proper atomic configuration that can dramatically enhance the contribution of the magnetic-dipole allowed transition via the atomic phase coherence. It is shown that the atomic system chosen with proper optical parameters can give rise to striking electromagnetic responses (leading to a negative refractive index) and that the atomic vapour becomes a left-handed medium in an optical frequency band. Differing from the previous schemes of artificial composite metamaterials (based on classical electromagnetic theory) to achieve the left-handed materials, which consist of anisotropic millimetre-scale composite structure units, the left-handed atomic vapour presented here is isotropic and homogeneous at the atomic-scale level. Such an advantage may be valuable in realizing the superlens (and hence perfect image) with left-handed atomic vapour.

  8. Modeling the Permittivity of Ferrite-Dielectric Composites

    Directory of Open Access Journals (Sweden)

    V.A. Astakhov

    2016-10-01

    Full Text Available The paper presents the model of ferrite-dielectric (ferroelectric composites with semiconductive powder fillers. Such media have the potential for designing systems with controlled frequency dispersion. Experimentally observed significant increase of effective dielectric permittivity in Mn-Zn ferrite composites with the semiconductor pellet is explained on the basis of the capacitance effect. Composites based on Ni-Zn ferrite, which have significantly higher electrical resistance, do not exhibit such phenomena and their behavior is described in the framework of the traditional models of effective medium approximation. There is proposed an analytical solution for the dielectric constant of the composite, based on consideration of the impedances of equivalent circuit involving initial materials (matrix and filler.

  9. L'argumentation dans la langue (Argumentation in Language)

    Science.gov (United States)

    Anscombre, J. C.; Ducrot, O.

    1976-01-01

    Questions the current distinction between semantics and pragmatics, and develops a theory of "argumentative scales" (Ducrot 1973), as well as a semantic model with three components and a revision of the notion of "illocutionary." (Text is in French.) (CDSH/AM)

  10. Den argumentative teksttype i reklamer

    DEFF Research Database (Denmark)

    Nielsen, Anne Ellerup

    1998-01-01

    - and macropropositions, it is a multicriterial model which takes into account both the syntactic, semantic and pragmatic features of texts. However, the model seems to offer some problems in establishing the limits between the argumentative and the descriptive text type. This imprecision is apparently due to the lack...... of distinction between the discourse potential of evaluative and referential propositions. This problem will be demonstrated on examples from the genre of advertising material which, because of its persuasive purpose, is particularly rich in argumentative features....

  11. Dependence of crystallizing phase dielectric permittivity on time of glass-ceramics sintering

    Directory of Open Access Journals (Sweden)

    Dmitriyev M. V.

    2010-10-01

    Full Text Available The paper deals with computing technique of effective dielectric permittivity of crystobalite formed in glass-ceramic body by means of measured dielectric permittivity of glass-ceramic composit. Dependence of the calculated parameter from the time of crystallization is found.

  12. Measuring the complex permittivity tensor of uniaxial biological materials with coplanar waveguide transmission line

    Science.gov (United States)

    A simple and accurate technique is described for measuring the uniaxial permittivity tensor of biological materials with a coplanar waveguide transmission-line configuration. Permittivity tensor results are presented for several chicken and beef fresh meat samples at 2.45 GHz....

  13. High-Temperature Permittivity and Data-Mining of Silicon Dioxide at GHz Band

    Institute of Scientific and Technical Information of China (English)

    YUAN Jie; WEN Bo; HOU Zhi-Ling; LU Ming-Ming; CAO Wen-Qiang; BA Chuan; FANG Xiao-Yong; CAO Mao-Sheng

    2012-01-01

    The high-temperature permittivity of quartz fibre-reinforced silicon dioxide (SiO2/SiO2 ) nano-composites is studied on the basis of the multi-scale theoretical model.We obtain the permittivity of the SiO2/SiO2 at high temperature,which is dependent on the temperature by data-mining.The result shows that the permittivity and loss tangent obtained by data-mining are well consistent with the measured ones.The high-temperature permittivity can be well predicted for SiO2/SiO2 by the as-proposed model and the data-mining method.%The high-temperature permittivity of quartz fibre-reinforced silicon dioxide (SiO2/SiO2) nano-composites is studied on the basis of the multi-scale theoretical model. We obtain the permittivity of the SiO2/SiO2 at high temperature, which is dependent on the temperature by data-mining. The resuJt shows that the permittivity and loss tangent obtained by data-mining are well consistent with the measured ones. The high-temperature permittivity can be well predicted for SiO2/SiO2 by the as-proposed model and the data-mining method.

  14. Silicone elastomers with high dielectric permittivity and high dielectric breakdown strength based on tunable functionalized copolymers

    DEFF Research Database (Denmark)

    Madsen, Frederikke Bahrt; Yu, Liyun; Daugaard, Anders Egede;

    2015-01-01

    High driving voltages currently limit the commercial potential of dielectric elastomers (DEs). One method used to lower driving voltage is to increase dielectric permittivity of the elastomer. A novel silicone elastomer system with high dielectric permittivity was prepared through the synthesis o...

  15. Silicone elastomers with high dielectric permittivity and high dielectric breakdown strength based on tunable functionalized copolymers

    DEFF Research Database (Denmark)

    Madsen, Frederikke Bahrt; Yu, Liyun; Daugaard, Anders Egede

    2015-01-01

    High driving voltages currently limit the commercial potential of dielectric elastomers (DEs). One method used to lower driving voltage is to increase dielectric permittivity of the elastomer. A novel silicone elastomer system with high dielectric permittivity was prepared through the synthesis o...

  16. Robust Location of Optical Fiber Modes via the Argument Principle Method

    CERN Document Server

    Chen, Parry Y

    2016-01-01

    We implement a robust, globally convergent root search method for transcendental equations guaranteed to locate all complex roots within a specified search domain, based on Cauchy's residue theorem. Although several implementations of the argument principle already exist, ours has several advantages: it allows singularities within the search domain and branch points are not fatal to the method. Furthermore, our implementation is simple and is written in MATLAB, fulfilling the need for an easily integrated implementation which can be readily modified to accommodate the many variations of the argument principle method, each of which is suited to a different application. We apply the method to the step index fiber dispersion relation, which has become topical due to the recent proliferation of high index contrast fibers. We also find modes with permittivity as the eigenvalue, catering to recent numerical methods that expand the radiation of sources by eigenmodes.

  17. The equivalent electrical permittivity of gas-solid mixtures at intermediate solid volume fractions.

    Energy Technology Data Exchange (ETDEWEB)

    Torczynski, John Robert; Ceccio, Steven Louis; Tortora, Paul Richard

    2005-07-01

    Several mixture models are evaluated for their suitability in predicting the equivalent permittivity of dielectric particles in a dielectric medium for intermediate solid volume fractions (0.4 to 0.6). Predictions of the Maxwell, Rayleigh, Bottcher and Bruggeman models are compared to computational simulations of several arrangements of solid particles in a gas and to the experimentally determined permittivity of a static particle bed. The experiment uses spherical glass beads in air, so air and glass permittivity values (1 and 7, respectively) are used with all of the models and simulations. The experimental system used to measure the permittivity of the static particle bed and its calibration are described. The Rayleigh model is found to be suitable for predicting permittivity over the entire range of solid volume fractions (0-0.6).

  18. Complex permittivity of representative biological solutions in the 2-67 GHz range.

    Science.gov (United States)

    Zhadobov, Maxim; Augustine, Robin; Sauleau, Ronan; Alekseev, Stanislav; Di Paola, Alessandra; Le Quément, Catherine; Mahamoud, Yonis Soubere; Le Dréan, Yves

    2012-05-01

    The main purpose of this study is to provide experimental data on the complex permittivity of some biological solutions in the 2-67 GHz range at room and human body temperatures. The permittivity measurements are performed using an open-ended coaxial probe. Permittivity spectra of several representative monomolecular solutions of proteins, amino acids, nucleic acids, and carbohydrates are analyzed and compared. Furthermore, measurements have also been performed for complex biomolecular solutions, including bovine serum albumin (BSA)-DNA-glucose mixture, culture medium, and yeast extract solution. The results demonstrate that for concentrations below 1%, the permittivity spectra of the solutions do not substantially differ from that of distilled water. Measurements carried out for 4% and 20% BSA solutions show that the presence of proteins results in a decrease in permittivity. For highly concentrated RNA solutions (3%), a slight increase in the imaginary part of the permittivity is observed below 10 GHz. Experimental data show that free water permittivity can be used for modeling of the culture medium above 10 GHz. However, at lower frequencies a substantial increase in the imaginary part of the permittivity due to ionic conductivity should be carefully taken into account. A similar increase has also been observed for the yeast extract solution in the lower frequency region of the considered spectrum. Above 10 GHz, the high concentration of proteins and other low-permittivity components of the yeast extract solution results in a decrease in the complex permittivity compared to that of water. Obtained data are of utmost importance for millimeter-wave dosimetry studies.

  19. Integrated processing in multimodal argumentation

    NARCIS (Netherlands)

    Hoven, P.J. van den; Jiang, W.

    2011-01-01

    The question addressed in this paper is simple. If the argumentative function of a multimodal narrative text requires the integration of the information from different modes, among which verbal ones, what model for the order of processing and the integration of information do we need to adopt? Using

  20. Argumentative Function in Child Discourse.

    Science.gov (United States)

    Albano, Maria-Grazia; And Others

    1985-01-01

    Describes a study of preschool children's utterances and their context, intended to provide evidence of children's argumentative capacities. Shows how children, though perhaps not consciously, use language to intervene upon reality in order to modify a state of things by sensibly arguing their case. (SED)

  1. Bad Arguments Defending Racial Preference

    Science.gov (United States)

    Cohen, Carl

    2008-01-01

    Professor Cohen describes the arduous path to the passage of Proposition 2 in Michigan in 2006. In considering the reasons for its victory, he shows how claims (sometimes well-intended) "for" preferences rest on truly bad arguments. (Contains 8 footnotes.)

  2. Topological arguments for Kolmogorov complexity

    Directory of Open Access Journals (Sweden)

    Alexander Shen

    2012-08-01

    Full Text Available We present several application of simple topological arguments in problems of Kolmogorov complexity. Basically we use the standard fact from topology that the disk is simply connected. It proves to be enough to construct strings with some nontrivial algorithmic properties.

  3. 75 FR 62591 - Oral Argument

    Science.gov (United States)

    2010-10-12

    ... given of the scheduling of oral argument in the matters of: Hyginus U. Aguzie v. Office of Personnel Management, MSPB Docket Number DC-0731-09-0261-R-1; Jenee Ella Hunt-O'Neal v. Office of Personnel Management, MSPB Docket Number AT-0731-09-0240-I-1; James A. Scott v. Office of Personnel Management, MSPB...

  4. Automating Workflow using Dialectical Argumentation

    NARCIS (Netherlands)

    Urovi, Visara; Bromuri, Stefano; McGinnis, Jarred; Stathis, Kostas; Omicini, Andrea

    2008-01-01

    This paper presents a multi-agent framework based on argumentative agent technology for the automation of the workflow selection and execution. In this framework, workflow selection is coordinated by agent interactions governed by the rules of a dialogue game whose purpose is to evaluate the workflo

  5. Eight Arguments against Double Effect

    DEFF Research Database (Denmark)

    Di Nucci, Ezio

    I offer eight arguments against the Doctrine of Double Effect, a normative principle according to which in pursuing the good it is sometimes morally permissible to bring about some evil as a side-effect or merely foreseen consequence: the same evil would not be morally justified as an intended...

  6. Origin of colossal dielectric permittivity of rutile Ti0.9In0.05Nb0.05O2: single crystal and polycrystalline

    Science.gov (United States)

    Song, Yongli; Wang, Xianjie; Sui, Yu; Liu, Ziyi; Zhang, Yu; Zhan, Hongsheng; Song, Bingqian; Liu, Zhiguo; Lv, Zhe; Tao, Lei; Tang, Jinke

    2016-01-01

    In this paper, we investigated the dielectric properties of (In + Nb) co-doped rutile TiO2 single crystal and polycrystalline ceramics. Both of them showed colossal, up to 104, dielectric permittivity at room temperature. The single crystal sample showed one dielectric relaxation process with a large dielectric loss. The voltage-dependence of dielectric permittivity and the impedance spectrum suggest that the high dielectric permittivity of single crystal originated from the surface barrier layer capacitor (SBLC). The impedance spectroscopy at different temperature confirmed that the (In + Nb) co-doped rutile TiO2 polycrystalline ceramic had semiconductor grains and insulating grain boundaries, and that the activation energies were calculated to be 0.052 eV and 0.35 eV for grain and grain boundary, respectively. The dielectric behavior and impedance spectrum of the polycrystalline ceramic sample indicated that the internal barrier layer capacitor (IBLC) mode made a major contribution to the high ceramic dielectric permittivity, instead of the electron-pinned defect-dipoles. PMID:26869187

  7. Perelman, argument ad hominem et ethos rhétorique Perelman, ad Hominem Argument, and Rhetorical Ethos

    Directory of Open Access Journals (Sweden)

    Michael Leff

    2009-04-01

    Full Text Available La conception de Perelman sur le rôle des personnes dans l’argumentation est l’une des marques les plus caractéristiques de sa rupture avec les hypothèses cartésiennes sur le raisonnement. Alors que le paradigme rationaliste cherchait à minimiser ou à éliminer les considérations personnelles comme étant dilatoires et non pertinentes dans ce cadre, Perelman insiste sur le fait que l’argumentation met inévitablement l’accent sur les personnes spécifiques impliquées dans l’argumentation et que la relation entre le locuteur et ce qui est dit est toujours pertinente et importante. En adoptant cette position, Perelman ressuscite implicitement la conception classique de la preuve par le caractère (argument par l’ethos ou « ethotique ». Mais, bien que la Nouvelle Rhétorique consacre une large place au débat sur l’acte et la personne dans l’argumentation, elle n’accorde pas beaucoup de réflexion au concept classique et mélange différentes approches à l’intérieur de la tradition. Le résultat est que Perelman traite le rôle du locuteur dans l’argumentation uniquement en référence à des techniques abstraites et ne prend pas en compte l’importance de l’examen des cas particuliers pour éclairer la compréhension du fonctionnement de l’argument ethotique en situation dans le contexte complexe de son utilisation effective. Par conséquent, la prise en compte par Perelman du rôle de la personne dans l’argumentation doit être complétée par la référence à des études de cas et c’est dans ce but que j’étudie l’argument ethotique dans le célèbre essai de W. E. B. DuBois « Sur M. Booker T. Washington et autres ».Perelman’s view of the role of persons in argument is one of the most distinctive features of his break with Cartesian assumptions about reasoning. Whereas the Rationalist paradigm sought to minimize or eliminate personal considerations by dismissing them as distracting and

  8. Modelling Imprecise Arguments in Description Logic

    Directory of Open Access Journals (Sweden)

    LETIA, I. A.

    2009-10-01

    Full Text Available Real arguments are a mixture of fuzzy linguistic variables and ontological knowledge. This paper focuses on modelling imprecise arguments in order to obtain a better interleaving of human and software agents argumentation, which might be proved useful for extending the number of real life argumentative-based applications. We propose Fuzzy Description Logic as the adequate technical instrumentation for filling the gap between human arguments and software agents arguments. A proof of concept scenario has been tested with the fuzzyDL reasoner.

  9. Wireless network of stand-alone end effect probes for soil in situ permittivity measurements over the 100MHZ-6GHz frequency range

    Science.gov (United States)

    Demontoux, François; Bircher, Simone; Ruffié, Gilles; Bonnaudiin, Fabrice; Wigneron, Jean-Pierre; Kerr, Yann

    2017-04-01

    , it should be useful to install many probes on the same site to obtain permittivity measurements over a large area. To reach this goal, the probes should communicate with each other to send data to a record device. Furthermore, it is needed to record measurements over a long time period (many months) to study the in-situ dielectric soil property variations according to changing weather conditions and seasonal trends. The goal of the research work presented is to develop a dielectric sensor system based on end effect probes able to communicate the data using wireless technology. It must be stand-alone from an electric and data recording point of view so it must integrate a VNA circuit instead of the ANRITSU VNA used for the moment. The LoRa wireless technology has been selected because of its low electric consumption and the large distance between equipment available. LoRaWAN™ is a Low Power Wide Area Network specification intended for wireless battery operated devices. The LoRaWAN data rates range from 0.3 kbps to 50 kbps which is sufficient for our probes' data exchanges. We will present the work done to perform the VNA and the LoRa communication board as well as the work done to improve the probes and the permittivity computation algorithm.

  10. Persuasive argumentation as a cultural practice

    Directory of Open Access Journals (Sweden)

    Paweł Gałkowski

    2014-06-01

    Full Text Available In this article author traces relation between argumentation and cultural practice. The first part focuses on definition of argumentation in informal logic tradition. In particular, it discusses argument in terms of verbal and social activity involving the use of everyday language. Author claims that there is no argumentation beyond language. The second part explains persuasive argumentation as a form of cultural practice. The persuasive arguments found in “social practice” can be understood as a social activity, analysable within the context of a given cultural system. Author refers to an approach taking the argumentative expression as a certain type of communicative practice, directed towards respecting, recognising or accepting specific actions. The inclusion of persuasive argumentation in the “circuit of cultural activities” to be studied makes it possible to compare this type of argumentation with other social practices, and to posit a clear historical dimension in the study of argumentation. It also makes it possible to view persuasive argumentation as one of many cultural activities aimed at changing or perpetuating behaviours, attitudes, thinking, etc. The third part of the paper concerns the problem of humanistic interpretation of persuasive argumentation. Author attempts to develop this intuition, at the same time demonstrating the problems that arise from this approach. In conclusion, author tries to analyze argumentation in terms of culture theory and humanistic interpretation.

  11. Towards Real-Time Argumentation

    Directory of Open Access Journals (Sweden)

    Vicente JULIÁN

    2016-07-01

    Full Text Available In this paper, we deal with the problem of real-time coordination with the more general approach of reaching real-time agreements in MAS. Concretely, this work proposes a real-time argumentation framework in an attempt to provide agents with the ability of engaging in argumentative dialogues and come with a solution for their underlying agreement process within a bounded period of time. The framework has been implemented and evaluated in the domain of a customer support application. Concretely, we consider a society of agents that act on behalf of a group of technicians that must solve problems in a Technology Management Centre (TMC within a bounded time. This centre controls every process implicated in the provision of technological and customer support services to private or public organisations by means of a call centre. The contract signed between the TCM and the customer establishes penalties if the specified time is exceeded.

  12. Snowpack permittivity profile retrieval from tomographic SAR data

    Science.gov (United States)

    Rekioua, Badreddine; Davy, Matthieu; Ferro-Famil, Laurent; Tebaldini, Stefano

    2017-01-01

    This work deals with 3D structure characterization and permittivity profile retrieval of snowpacks by tomographic SAR data processing. The acquisition system is a very high resolution ground based SAR system, developed and operated by the SAPHIR team, of IETR, University of Rennes-1 (France). It consists mainly of a vector network analyser and a multi-static antenna system, moving along two orthogonal directions, so as to obtain a two-dimensional synthetic array. Data were acquired during the AlpSAR campaign carried by the European Space Agency and led by ENVEO. In this study, tomographic imaging is performed using Time Domain Back Projection and consists in coherently combining the different recorded backscatter contributions. The assumption of free-space propagation during the focusing process is discussed and illustrated by focusing experimental data. An iterative method for estimating true refractive indices of the snow layers is presented. The antenna pattern is also compensated for. The obtained tomograms after refractive index correction are compared to the stratigraphy of the observed snowpack.

  13. RHETORICAL STRUCTURE OF ARGUMENTATIVE ANSWER

    Directory of Open Access Journals (Sweden)

    Juliano Desiderato ANTONIO

    2014-12-01

    Full Text Available The aim of this paper is to describe the rhetorical structure of the argumentative answer genre in a corpus formed by 15 compositions of the winter vestibular of Universidade Estadual de Maringá. The instrument of analysis used in the investigation was RST (Rhetorical Structure Theory. The initial statement was considered the central unit of the argumentative answer. Most of the writers held evidence relation between the central unit (nucleus and the expansion (satellite. Evidence relation is interpersonal and the aim of the writers is to convince their addressees (in this case the compositions evaluation committee that their point is correct. Within the initial statement, the relation with higher frequency was contrast. Our hypothesis is that the selection of texts of the test influenced the applicants to present positive and negative aspects of the internet. In the higher level of the expansion text span, list is the most frequent relation because the applicants present various arguments with the same status. Contrast was the second relation with highest frequency in this same level. Our hypothesis is that the selection of texts of the test influenced the applicants to present positive and negative aspects of the internet as it happened in the initial statement. Within the 15 compositions, 12 had a conclusion. This part was considered a satellite of the span formed by the initial statement and its expansion. The relation held was homonymous.

  14. Numerical calculation of the rock permittivity using micro computerized tomography image

    Science.gov (United States)

    Guo, Chen; Liu, Richard; Jin, Zhao; He, Zhili

    2014-05-01

    A numerical evaluation of the permittivity of sandstones through the micro computerized tomography (micro CT) images at 1.1 GHz is conducted by using an image porosity extracting algorithm and an improved Finite Difference Method (FDM). Within the acquired physical properties by 3D micro CT scanning, numerical method is used to compute the permittivity of the rock samples. A resonant cavity is used for experimental measurement. The simulated results of 2 clastic sandstone samples with dry state and saturated state are compared with experimental data for validating the accuracy of the proposed numerical method. The results show great agreement and the error of permittivity evaluation is less than 3%.

  15. Modified Hilbert transform pair and Kramers-Kronig relations for complex permittivities

    Science.gov (United States)

    Cockrell, C. R.

    1990-01-01

    Modified versions of the Hilbert transform pair and the Kramers-Kronig relations are derived for the complex permittivity of a plasma/dielectric medium which is singular at the frequency of the applied electric field equal to 0. Such a complex permittivity exists when the plasma/dielectric model allows a loss term but no restoring term. Permittivity, in which both loss and restoring terms are included, is shown to satisfy the standard Hilbert transform pair and, thus, the Kramers-Kronig relations.

  16. Social Values as Arguments: Similar is Convincing

    Directory of Open Access Journals (Sweden)

    Gregory R Maio

    2014-08-01

    Full Text Available Politicians, philosophers, and rhetors engage in co-value argumentation: appealing to one value in order to support another value (e.g., equality leads to freedom. Across four experiments in the United Kingdom and India, we found that the psychological relatedness of values affects the persuasiveness of the arguments that bind them. Experiment 1 found that participants were more persuaded by arguments citing values that fulfilled similar motives than by arguments citing opposing values. Experiments 2 and 3 replicated this result using a wider variety of values, while finding that the effect is stronger among people higher in need for cognition and that the effect is mediated by the greater plausibility of co-value arguments that link motivationally compatible values. Experiment 4 extended the effect to real-world arguments taken from political propaganda and replicated the mediating effect of argument plausibility. The findings highlight the importance of value relatedness in argument persuasiveness.

  17. Giving Reasons, A Contribution to Argumentation Theory

    Directory of Open Access Journals (Sweden)

    Lilian Bermejo-Luque

    2011-10-01

    Full Text Available In Giving Reasons: A Linguistic-pragmatic-approach to Argumentation Theory (Springer, 2011, I provide a new model for the semantic and pragmatic appraisal of argumentation. This model is based on a characterization of argumentation as a second order speech-act complex. I explain the advantages of this model respecting other proposals within Argumentation Theory, such as Pragma-dialectics, Informal Logic, the New Rhetoric or the Epistemic Approach.

  18. Zero expression of arguments in Old Danish

    DEFF Research Database (Denmark)

    Heltoft, Lars

    2014-01-01

    arguments in Scanic are semantically different from pronouns, and therefore pronouns and zero arguments are not variants. At one level, zero arguments and pronouns are similar with respect to function, namely to supply means for establishing co-reference in text; however, they are not semantically...

  19. Social Argumentation in Online Synchronous Communication

    Science.gov (United States)

    Alagoz, Esra

    2013-01-01

    The ability to argue well is a valuable skill for students in both formal and informal learning environments. While many studies have explored the argumentative practices in formal environments and some researchers have developed tools to enhance the argumentative skills, the social argumentation that is occurring in informal spaces has yet to be…

  20. Effects of Dyadic Interaction on Argumentative Reasoning.

    Science.gov (United States)

    Kuhn, Deanna; Shaw, Victoria; Felton, Mark

    1997-01-01

    Tested hypothesis that thinking about a topic enhances later reasoning quality about that topic. Found that, when young adolescents and adults discussed capital punishment, their range of different arguments increased, they shifted from one-sided to two-sided arguments, arguments were based within a framework of alternatives, and they were more…

  1. Crystalline Structure, Defect Chemistry and Room Temperature Colossal Permittivity of Nd-doped Barium Titanate.

    Science.gov (United States)

    Sun, Qiaomei; Gu, Qilin; Zhu, Kongjun; Jin, Rongying; Liu, Jinsong; Wang, Jing; Qiu, Jinhao

    2017-02-13

    Dielectric materials with high permittivity are strongly demanded for various technological applications. While polarization inherently exists in ferroelectric barium titanate (BaTiO3), its high permittivity can only be achieved by chemical and/or structural modification. Here, we report the room-temperature colossal permittivity (~760,000) obtained in xNd: BaTiO3 (x = 0.5 mol%) ceramics derived from the counterpart nanoparticles followed by conventional pressureless sintering process. Through the systematic analysis of chemical composition, crystalline structure and defect chemistry, the substitution mechanism involving the occupation of Nd(3+) in Ba(2+) -site associated with the generation of Ba vacancies and oxygen vacancies for charge compensation has been firstly demonstrated. The present study serves as a precedent and fundamental step toward further improvement of the permittivity of BaTiO3-based ceramics.

  2. Enhancing relative permittivity by incorporating PDMS-PEG multiblock copolymers in binary polymer blends

    DEFF Research Database (Denmark)

    A Razak, Aliff Hisyam; Szabo, Peter; Skov, Anne Ladegaard

    Polydimethylsiloxane (PDMS) elastomers are well-known to be soft and highly stretchable, yet they never achieve maximum elongation when utilised as dielectric elastomers, simply because their dielectric permittivity remains rather low. Conversely, polyethyleneglycols (PEG) are not stretchable...

  3. Characterization of CVD graphene permittivity and conductivity in micro-/millimeter wave frequency range

    Directory of Open Access Journals (Sweden)

    Yunqiu Wu

    2016-09-01

    Full Text Available The permittivity and conductivity of chemical vapor deposited monolayer graphene are investigated up to 40 GHz. The characterization method is based on a coplanar waveguide transmission line structure that is fabricated on a multilayer substrate of Si/SiO2/graphene/Al2O3 from the bottom up. The effective relative permittivity of the coplanar waveguide transmission line is extracted using Thru-Reflect-Line calibration and scattering parameter measurements, and then the relative permittivity and corresponding conductivity of graphene are characterized using partial capacitance techniques. The results demonstrate that the conductivity and sheet resistance are remarkably frequency-dependent and that the complex relative permittivity is consistent with the Drude model.

  4. Permittivity Investigations of the Road Construction Raw Materials for Purposes of GPR Data Interpretations

    Science.gov (United States)

    Krysiński, Lech

    2014-05-01

    Permittivity is the major material property governing the formation of GPR response signal in diagnostic measurements. Every quantitative interpretation refers explicitly or implicitly to discussion of permittivity values. Thus, the recognition of permittivity for materials typical of the given technological area is necessary to make use of diagnostic measurements. Collection of several tens of stone cores representing different outcrops was investigated in order to obtain cross-sectional view of permittivity for stone materials being in use in Polish road construction industry as components of stone-asphalt mixtures. The main task was to estimate the typical permittivity values for stone materials treated as representation of several major petrological types. The capacimetry (at 50 MHz) was used as major and very efficient method of permittivity assessment and formation of the samples was subordinated to demands of this method. This method allows for determination of permittivity variability on the lateral surface of the cylindrical sample, giving the insight into the major features of the permittivity spatial distribution characteristic for the given rock. For the most homogeneous samples (in terms of permittivity distribution) the permittivity was measured also on the core top at frequency 2 GHz using impulse GPR reflectometry. No clear proofs for considerable permittivity frequency dependence were found (in the frame of the two methods precision) for these rocks. This conclusion can be related generally to major rock-forming minerals at least in dry igneous rocks. Only solid rocks obtained from regular massive outcrops were included to this first cross-sectional sampling, while artificial synthetic materials and natural gravels of postglacial origin were omitted since additional problems occur in these cases. This first experience allowed to recognize practical problems related to the sampling procedure. The collected data allow for provisional identification

  5. Argumentation, Dialogue Theory, and Probability Modeling: Alternative Frameworks for Argumentation Research in Education

    Science.gov (United States)

    Nussbaum, E. Michael

    2011-01-01

    Toulmin's model of argumentation, developed in 1958, has guided much argumentation research in education. However, argumentation theory in philosophy and cognitive science has advanced considerably since 1958. There are currently several alternative frameworks of argumentation that can be useful for both research and practice in education. These…

  6. Trait Argumentativeness, Verbal Aggressiveness, and Minimally Rational Argument: An Observational Analysis of Friendship Discussions.

    Science.gov (United States)

    Semic, Beth A.; Canary, Daniel J.

    1997-01-01

    Finds that argumentativeness and verbal aggressiveness did not correlate with the development and defense of undergraduate students' ideas but that the dyad's composition (in terms of argumentativeness and verbal aggressiveness) affected the proportion of ideas developed through argument. Suggests that argumentativeness and aggressiveness research…

  7. Silicone elastomers with high dielectric permittivity and high dielectric breakdown strength based on dipolar copolymers

    DEFF Research Database (Denmark)

    Madsen, Frederikke Bahrt; Yu, Liyun; Daugaard, Anders Egede;

    2014-01-01

    Dielectric elastomers (DES) are a promising new transducer technology, but high driving voltages limit their current commercial potential. One method used to lower driving voltage is to increase dielectric permittivity of the elastomer. A novel silicone elastomer system with high dielectric permi......-4-nitrobenzene. Here, a high increase in dielectric permittivity (similar to 70%) was obtained without compromising other favourable DE properties such as elastic modulus, gel fraction, dielectric loss and electrical breakdown strength. © 2014 Elsevier Ltd. All rights reserved....

  8. Experimental determination of blood permittivity and conductivity in simple shear flow.

    Science.gov (United States)

    Balan, Corneliu; Balut, Corina; Gheorghe, Liana; Gheorghe, Cristian; Gheorghiu, Eugen; Ursu, George

    2004-01-01

    The paper is concerned with the determination of blood permittivity and conductivity in Poiseuille and Couette simple shear flows. The experimental procedure, based on dielectric spectroscopy, evidences the sensitivity of blood electric properties to the applied frequency and local shear rate magnitude. The method evidences the possibility to correlate (for well-defined flow geometry) magnitude of shear rate, and consequently the shear stress level, with spectra permittivity of blood.

  9. Experimental study of composite medium with simultaneously negative permeability and permittivity

    Institute of Scientific and Technical Information of China (English)

    SUI Qiang; LI Fang

    2004-01-01

    This paper focuses on a composite medium structure that exhibits simultan-eously negative values of effective permeability and permittivity, and our experimental study in an anechoic chamber. The experiment results show that the artificial medium, based on a periodic array of interspaced conducting nonmagnetic split ring resonators and continuous metallic wires, can have a simultaneously negative effective permeability and permittivity within a frequency region in the microwave regime under certain linearly polarized waves.

  10. A Quasi-Optical Method for Measuring the Complex Permittivity of Materials.

    Science.gov (United States)

    1984-09-01

    millimeter wavelengths, waveguide, cavity, and various forms of quasi-optical methods are utilized to measure the complex permittivity of materials...conjunction with an interferometer, Fourier transform spectrometry can be utilized to derive the * permittivity of materials (Ref. 17). Breeden and...pp. 75-84, 1971. [17] J. E. Chamberlain, J. E. Gibbs, and H. A. Gebbie, " Refractometry in the far infra-red using a two-beam interferometer," Nature

  11. A new heterodyne-beat circuit for the determination of static permittivity

    Science.gov (United States)

    Castex, Teodosia Arauz; de Vivar, Pedro Díaz; Paz, María B. Rebollo; Buep, Adrián H.

    1995-04-01

    A greatly improved heterodyne-beat oscillator was built using integrated circuits, to measure static permittivity of liquid samples. Frequency variation of the oscillator is of less than 0.7 Hz/h; that corresponds to a capacity variation of less than 0.005 pF/h. Permittivity can be measured with a precision of 0.003% and an accuracy better than 0.01%.

  12. The effect of external factors on dielectric permittivity of Rochelle salt: humidity, annealing, stresses, electric field

    Directory of Open Access Journals (Sweden)

    A.G.Slivka

    2005-01-01

    Full Text Available The effect of external factors, such as dessicating/wetting, thermal annealing, uniaxial and hydrostatic pressure, on the dielectric permittivity of Rochelle salt crystals is investigated. The obtained results are compared with the available literature data and analyzed within the phenomenological Landau approach. A significant effect of the internal polar point defects in crystals and storage conditions on the dielectric permittivity is shown.

  13. Oral genres, argumentation and teaching

    Directory of Open Access Journals (Sweden)

    Zilda G. O. Aquino

    2015-02-01

    Full Text Available This paper aims at dealing with issues related to language spoken in the classroom, focusing on discursive practices that highlight argumentation. We believe that the discussions that were made around genres, especially guided by the studies of Bakhtin and Text Linguistics, have been providing a breakthrough towards the necessity for the school to promote language teaching through the discursive genre approach. That is what we expect to be happening since both writing and spoken modalities deserve space in learning. We believe that oral genres demand that teachers acquire specific knowledge of the features of spoken language interaction that arise from its use in practical situations. Because these studies are recent among our researchers (not longer than three decades, they should still be very present in our discussions. In this paper, we focus on a specific genre of oral tradition – the debate. It is ideal for knowledge building and taking a stand at issues that arise in society, all of which is particularly important to the school. Besides contributing to the development of skills required by certain sociodiscursive practices, it is proposed that the teaching of argumentation in oral genres concentrate on the observation of selected strategies in interactions. We are particularly interested in interactions that emerge when one interaction party is trying to persuade the other. The corpus consists of the transcriptions of debates which occurred both in the classroom and in other contexts, such as the media. The methodological approach is done by identifying the arguments and their strategic use in specific situations. The theoretical discussion rests on the works of Orecchioni (2010, Marcuschi (2004, Dolz and Schneuwly (2004, Perelman and Olbrechts-Tyteca (1996 [1958], among others.

  14. Microwave DENSITY—INDEPENDENT Permittivity Functions as Spring Oats Kernels' Moisture Calibrators: a New Approach

    Science.gov (United States)

    Das, Priyanka; Ahmad, Zeeshan; Singh, P. N.; Prasad, Ashutosh

    2011-11-01

    The present work makes use of experimental data for real part of microwave complex permittivity of spring oats (Avena sativa L.) at 2.45 GHz and 24 °C as a function of moisture content, as extracted from the literature. These permittivity data were individually converted to those for solid materials using seven independent mixture equations for effective permittivity of random media. Moisture dependent quadratic models for complex permittivity of spring oats (Avena sativa L.), as developed by the present group, were used to evaluate the dielectric loss factor of spring oats kernels. Using these data, seven density—independent permittivity functions were evaluated and plotted as a function of moisture content of the samples. Second and third order polynomial regression equations were used for curve fittings with these data and their performances are reported. Coefficients of determination (r2) approaching unity (˜ 0.95-0.9999) and very small Standard Deviation (SD) ˜0.001-8.87 show good acceptability for these models. The regularity in the nature of these variations revealed the usefulness of the density—independent permittivity functions as indicators/calibrators of moisture content of spring oats kernels. Keeping in view the fact that moisture content of grains and seeds is an important factor determining quality and affecting the storage, transportation, and milling of grains and seeds, the work has the potentiality of its practical applications.

  15. Low-order statistics of effective permittivity and electric field fluctuations in two-phase heterostructures

    Science.gov (United States)

    Shamoon, D.; Lasquellec, S.; Brosseau, C.

    2017-07-01

    Understanding the collective, low-frequency dielectric properties of heterostructures is a major goal in condensed matter. In 1935, Bruggeman [Ann. Phys. Lpz. 24, 636 (1935)] conceived the concept of an effective medium approximation (EMA) involving a decoupling between the low-order statistics of the electric field fluctuations and the characteristic length scales. We report on and characterize, via finite element studies, the low-order statistics effective permittivity of two-phase 2D and 3D random and deterministic heterostructures as geometry, phase permittivity contrast, and inclusion content are varied. Since EMA analytical expressions become cumbersome even for simple shapes and arrangements, numerical approaches are more suitable for studying heterostructures with complex shapes and topologies. Our numerical study verifies the EMA analytic predictions when the scales are well-separated. Our numerical study compares two approaches for calculating effective permittivity by explicit calculations of local average fields and energy as geometry, phase permittivity contrast, and inclusion content are varied. We study the conditions under which these approaches give a reliable estimate of permittivity by comparing with 2D/3D EMA analytical models and duality relation. By considering 2D checkerboards which consist of a multitude of contiguous N × N square cells, the influence of the internal length scale (i.e., N) on permittivity is discussed.

  16. Geometric covering arguments and ergodic theorems for free groups

    CERN Document Server

    Bowen, Lewis

    2009-01-01

    We present a new approach to the proof of ergodic theorems for actions of free groups based on geometric covering and asymptotic invariance arguments. Our approach can be viewed as a direct generalization of the classical geometric covering and asymptotic invariance arguments used in the ergodic theory of amenable groups. We use this approach to generalize the existing maximal and pointwise ergodic theorems for free group actions to a large class of geometric averages which were not accessible by previous techniques. Some applications of our approach to other groups and other problems in ergodic theory are also briefly discussed.

  17. Laughlin's argument for the quantized thermal Hall effect

    CERN Document Server

    Nakai, Ryota; Nomura, Kentaro

    2016-01-01

    We extend Laughlin's magnetic-flux-threading argument to the quantized thermal Hall effect. A proper analogue of Laughlin's adiabatic magnetic-flux threading process for the case of the thermal Hall effect is given in terms of an external gravitational field. From the perspective of the edge theories of quantum Hall systems, the quantized thermal Hall effect is closely tied to the breakdown of large diffeomorphism invariance, that is, a global gravitational anomaly. In addition, we also give an argument from the bulk perspective in which a free energy, decomposed into its Fourier modes, is adiabatically transferred under an adiabatic process involving external gravitational perturbations.

  18. The estimate of permittivity of anisotropic composites with lamellar inclusions by the self-assessment method

    Directory of Open Access Journals (Sweden)

    V. S. Zarubin

    2015-01-01

    Full Text Available Composites are widely used as structural or thermal protection materials; they are used as well as functional materials in a large number of different electrical devices and as dielectrics. This composite has one of the most important characteristics the relative permittivity. It depends primarily on the dielectric properties of the inclusions and the matrix as well as the shape and volume content of the inclusions.In this paper, a mathematical model of the interaction of the electrostatic fields in an isotropic plate and in the surrounding homogeneous anisotropic medium is constructed. This model describes the dielectric properties of the composite with such inclusions. A variant of the same orientation of lamellar inclusions is considered, which leads to the special case of anisotropy of the dielectric properties of the composite that has transverse isotropy towards the direction perpendicular to the inclusions. The shape of inclusions is represented as an oblate ellipsoid of revolution (spheroid. Transformation of the differential equation describing the distribution of the electric potential transversely to isotropic medium surrounding the spheroidal inclusion, to the Laplace equation with the subsequent transition from the initial spheroid to the given ellipsoid of rotation allows us to apply the self-assessment method for the determination of the dielectric properties of the composite. This method equates the result of averaging the perturbation of the electrostatic field in the inclusions and the matrix particles towards the unperturbed fields in the environment to zero.The constructed mathematical model allows us to determine the electrostatic field disturbance in the inclusions and the matrix particles towards the unperturbed field given in the environment at a distance from the inclusions and the matrix particles, much larger than their characteristic dimensions. By averaging the perturbation of the electrostatic field in all the

  19. Role of Relaxation on the Giant Permittivity and Electrical Properties of CaCu3Ti4O12 Ceramics

    Science.gov (United States)

    Zhao, Xuetong; Ren, Lulu; Liao, Ruijin; Li, Jianying; Yang, Lijun; Wang, Feipeng

    2016-06-01

    CaCu3Ti4O12 (CCTO) ceramics were synthesized under various sintering conditions to investigate the role of relaxation on permittivity and electrical properties. Two relaxation processes that respectively related to grain and to domain boundary at a temperature as low as 223 K were fitted according to the Cole-Cole theory. The results indicate that both relaxations largely account for the giant permittivity of CCTO ceramics. Moreover, the relaxation behaviors of grain and of the grain boundary can be processed via impedance plots that vary from 113 K to 473 K. It is shown that longer sintering duration leads to lower resistance of grain and of grain boundary: e.g., from 3200 Ω to 810 Ω and 1.76 MΩ to 0.48 MΩ, respectively. The activation energy related to grain-boundary relaxation drops from 1.14 eV to 0.80 eV, while the value of grain stays unchanged at about 0.11 eV. The Schottky barrier of the CCTO sample decreases from 0.65 eV to 0.57 eV. It is also proposed that the nonlinearity of current-voltage property for CCTO ceramics may be strongly related to the relaxation processes of grain boundaries.

  20. Applying Argumentation Analysis To Assess the Quality of University Oceanography Students' Scientific Writing.

    Science.gov (United States)

    Takao, Allison Y.; Prothero, William A.; Kelly, Gregory J.

    2002-01-01

    Presents the methods and results of an assessment of students' scientific writing. Studies an introductory oceanography course in a large public university that used an interactive CD-ROM, "Our Dynamic Planet". Analyzes the quality of students' written arguments by using a grading rubric and an argumentation analysis model. Includes 18…

  1. Prototypical argumentative patterns in a legal context: The role of pragmatic argumentation in the justification of judicial decisions

    NARCIS (Netherlands)

    E.T. Feteris

    2016-01-01

    In this contribution the prototypical argumentative patterns are discussed in which pragmatic argumentation is used in the context of legal justification in hard cases. First, the function and implementation of pragmatic argumentation in prototypical argumentative patterns in legal justification are

  2. Belief Revision and Argumentation Theory

    Science.gov (United States)

    Falappa, Marcelo Alejandro; Kern-Isberner, Gabriele; Simari, Guillermo Ricardo

    Belief revision is the process of changing beliefs to adapt the epistemic state of an agent to a new piece of information. The logical formalization of belief revision is a topic of research in philosophy, logic, and in computer science, in areas such as databases or artificial intelligence. On the other hand, argumentation is concerned primarily with the evaluation of claims based on premises in order to reach conclusions. Both provide basic and substantial techniques for the art of reasoning, as it is performed by human beings in everyday life situations and which goes far beyond logical deduction. Reasoning, in this sense, makes possible to deal successfully with problems in uncertain, dynamic environments and has been promoting the development of human societies.

  3. CLAD DEGRADATION - FEPS SCREENING ARGUMENTS

    Energy Technology Data Exchange (ETDEWEB)

    R. Schreiner

    2004-10-21

    The purpose of this report is to evaluate and document the screening of the clad degradation features, events, and processes (FEPs) with respect to modeling used to support the Total System Performance Assessment-License Application (TSPA-LA). This report also addresses the effect of certain FEPs on both the cladding and the commercial spent nuclear fuel (CSNF), DOE-owned spent nuclear fuel (DSNF), and defense high-level waste (DHLW) waste forms, as appropriate to address the effects on multiple materials and both components (FEPs 2.1.09.09.0A, 2.1.09.11.0A, 2.1.11.05.0A, 2.1.12.02.0A, and 2.1.12.03.0A). These FEPs are expected to affect the repository performance during the postclosure regulatory period of 10,000 years after permanent closure. Table 1-1 provides the list of cladding FEPs, including their screening decisions (include or exclude). The primary purpose of this report is to identify and document the analysis, screening decision, and TSPA-LA disposition (for included FEPs) or screening argument (for excluded FEPs) for these FEPs related to clad degradation. In some cases, where a FEP covers multiple technical areas and is shared with other FEP reports, this report may provide only a partial technical basis for the screening of the FEP. The full technical basis for shared FEPs is addressed collectively by the sharing FEP reports. The screening decisions and associated TSPA-LA dispositions or screening arguments from all of the FEP reports are cataloged in a project-specific FEPs database.

  4. Argumentative Support for Structured HACCP Plans

    Directory of Open Access Journals (Sweden)

    GROZA, A.

    2010-05-01

    Full Text Available This research presents an argumentation based decision support system for implementing the Hazard Analysis at Critical Control Points (HACCP standard in food industry. Our analysis starts by identifying the adequate technical instrumentation needed for supporting different aspects of the HAACP system. An integrated architectural solution is presented. The framework is built around concept maps and it exploits the integration of ontologies with argumentation theory by using the Argument Interchange Format ontology.

  5. Argument structure frames: a lexical complexity metric?

    Science.gov (United States)

    Schmauder, A R

    1991-01-01

    The number of semantic argument structure frames associated with a verb has been reported to influence ease of processing during language comprehension. The present experiments tested the generality of the argument structure complexity effect with three dependent measures: eye-fixation times, naming latencies, and lexical decision latencies. Two eye-movement experiments and two experiments using cross-modal tasks failed to provide evidence supporting the argument structure complexity effect. The present experiments indicated that results reflecting verbs' argument structure complexity are not generalizable.

  6. The Concept of Justice: Argumentation and Dialogism

    Directory of Open Access Journals (Sweden)

    Ana Lúcia Tinoco Cabral

    2014-06-01

    Full Text Available This paper presents a reflection attempting to situate the concepts of justice and argumentation in Perelman’s approach in dialogue with the Bakhtin Circle’s theories. For this purpose, it analyses the concept of justice, deals with the concept of argumentation in order to situate its field and to emphasize how it supports the concept of justice, highlights the ethical and dialogical aspects of legal argumentation, establishing connections between Perelman’s ideas and dialogic principles of language, and, finally, attempts to show how different voices intersect in the argumentative confrontation through the analysis of two excerpts of legal discourses.

  7. Novel permittivity test for determination of yeast surface charge and flocculation abilities.

    Science.gov (United States)

    Kregiel, Dorota; Berlowska, Joanna; Szubzda, Bronisław

    2012-12-01

    Yeast flocculation has been found to be important in many biotechnological processes. It has been suggested that flocculation is promoted by decreasing electrostatic repulsion between cells. In this study, we used an unconventional rapid technique--permittivity test--for determination of the flocculation properties and surface charge values of three industrial yeast strains with well-known flocculation characteristics: Saccharomyces cerevisiae NCYC 1017 (brewery, ale), S. pastorianus NCYC 680 (brewery, lager), and Debaryomyces occidentalis LOCK 0251 (unconventional amylolytic yeast). The measurements of permittivity were compared with the results from two classical methods for determination of surface charge: Alcian blue retention and Sephadex DEAE attachment. The permittivity values for particular strains correlated directly with the results of Alcian blue retention (r = 0.9). The results also confirmed a strong negative relationship between the capacitance of yeast suspensions and their flocculation abilities. The highest permittivity was noted for the ale strain NCYC 1017, with weak flocculation abilities, and the lowest for the flocculating lager yeast NCYC 680. This paper is the first to describe the possibility of using a rapid permittivity test to evaluate the surface charge of yeast cells and their flocculation abilities. This method is of practical value in various biotechnological industries where flocculation is applied as a major method of cell separation.

  8. A convenient method for complex permittivity measurement of thin materials at microwave frequencies

    Energy Technology Data Exchange (ETDEWEB)

    Chung, B K [Faculty of Engineering, Multimedia University, 63100 Cyberjaya (Malaysia)

    2006-05-07

    A practical problem in the reflection method for measuring permittivity of thin materials is the difficulty in ensuring the sample is placed exactly at the waveguide flange. A small position offset of the dielectric slab will give rise to significant errors in calculating the permittivity. To circumvent this problem, a measurement method using a waveguide partially filled with a thin material slab has been developed. The material sample can be easily prepared and inserted into the guide through a longitudinal slot on the broad wall of the waveguide. Multiple material slabs can be measured rapidly because one does not have to disconnect the waveguide system for sample placement. The method is verified with measurement of Teflon, glass and FR4 fibreglass. The measured permittivity show good agreement with published data. Subsequently, the permittivity of a vegetation leaf was measured. The method presented in this paper is particularly useful in measuring the permittivity of a thin and narrow slab of natural materials such as a paddy leaf.

  9. Measurement of the relative permittivities of rock for georadar exploration in mega-hertz band

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jung Ho; Chung, Seung Hwan; Cho, In Ky [Korea Institute of Geology Mining and Materials, Taejon (Korea, Republic of)

    1996-10-31

    The relative permittivities of rocks sampled in Korea were measured in the mega-hertz frequency band to provide the basic physical property for the georadar exploration. Measurements were done by using the system of BGR (Budesanstalt fur Geowissenschaften und Rohstoffe) of Germany. The measurement system is based on the principle of the resonance phenomena of simple RLC circuitry. The permittivities measured in 10-20 MHz band are presented for Cretaceous Bulguksa granite, Jurassic Daebo granite, gneiss, quartzite, limestone, shale, and Hwangsan tuff. Owing to the preparation of tested samples cut in two mutually orthogonal planes, we could measure the anisotropy. Shale and gneiss are revealed to be highly anisotropic and granite shows nearly isotropic. Measurements using various frequencies showed the dependence of permittivities on the frequency variation. The permittivities of shale and tuff changed greatly more than 40 % when frequenc= y varied from 1 to 70 MHz. Those of granite, gneiss, and limestone also showed the dependence on the frequency, but negligible within the measuring frequency band. Based on the permittivity measurements, the radar wave velocities were estimated for the georadar survey using the antenna with the central frequencies of 20 and 50 MHz. (author). 7 refs., 4 tabs., 8 figs.

  10. Colossal permittivity induced by lattice mirror reflection symmetry breaking in Ba7Ir3O13+x(0 <= x <= 1.5) epitaxial thin films

    Science.gov (United States)

    Miao, Ludi; Xin, Yan; Zhu, Huiwen; Xu, Hong; Luo, Sijun; Talbayev, Diyar; Stanislavchuk, T. N.; Sirenko, A. A.; Mao, Zhiqiang

    2014-03-01

    Materials with colossal permittivity (CP) at room temperature hold tremendous promise in modern microelectronics as well as high-energy-density storage applications. Despite several proposed mechanisms that lead torecent discoveries of a series of new CP materials such as Nb, In co-doped TiO2 and CaCu3Ti4O12 ceramics, it is imperative to find other approaches which can further guide the search for new CP materials. In this talk, we will demonstrate a new mechanism for CP: the breaking of mirror reflection symmetry of lattice can cause CP. This mechanism was revealed in a new layered iridate Ba7Ir3O13+x (BIO) thin film we recently discovered. Structural characterization of BIO films show that its mirror reflection symmetry is broken along b-axis, but preserved along a- and c-axes. Dielectric property measurements of BIO films at room temperature show a CP (103-10<4) along the in-plane direction, but a much smaller permittivity (10- 20) along the c-axis, in the 102- 106 Hz frequency range. Such unusually large anisotropy in permittivity testifies to the significant role of the structural in-plane mirror reflection symmetry breaking in inducing CP. This work is supported by DOD-ARO under Grant No. W911NF0910530.

  11. Estimation of Relative Permittivity of Printed Circuit Board with Fiber Glass Epoxy as Dielectric for UHF Applications

    Directory of Open Access Journals (Sweden)

    Ronal D. Montoya-Montoya

    2013-11-01

    Full Text Available This paper presents the results of measuring relative permittivity of fiber glass printed circuit board (PCB’s, using a rectangular resonant cavity. The relative permittivity is presented as function of frequency. To obtain resonant frequencies, the return loss was measured using a network analyzer. Relative permittivity was calculated by finding frequencies of resonant cavity modes. The results are presented in a frequency span of 1 to 3.5GHz. It was clearly shown the nonlinear behavior of the relative permittivity for the dielectric laminate evaluated, even what happens respect to the frequency of the resonant modes below and above to frequency of 2 GHz.

  12. Argumentation Within Language as Subsidy for the Evaluation of Reading Practices and Production of Argumentative Texts

    National Research Council Canada - National Science Library

    Lauro Gomes

    2016-01-01

    This paper aims to present an evaluation proposal of the performance in reading and writing dissertative-argumentative texts, based on principles and concepts from the theory of Argumentation in Language...

  13. Examining Elementary Students' Development of Oral and Written Argumentation Practices Through Argument-Based Inquiry

    Science.gov (United States)

    Chen, Ying-Chih; Hand, Brian; Park, Soonhye

    2016-05-01

    Argumentation, and the production of scientific arguments are critical elements of inquiry that are necessary for helping students become scientifically literate through engaging them in constructing and critiquing ideas. This case study employed a mixed methods research design to examine the development in 5th grade students' practices of oral and written argumentation from one unit to another over 16 weeks utilizing the science writing heuristic approach. Data sources included five rounds of whole-class discussion focused on group presentations of arguments that occurred over eleven class periods; students' group writings; interviews with six target students and the teacher; and the researcher's field notes. The results revealed five salient trends in students' development of oral and written argumentative practices over time: (1) Students came to use more critique components as they participated in more rounds of whole-class discussion focused on group presentations of arguments; (2) by challenging each other's arguments, students came to focus on the coherence of the argument and the quality of evidence; (3) students came to use evidence to defend, support, and reject arguments; (4) the quality of students' writing continuously improved over time; and (5) students connected oral argument skills to written argument skills as they had opportunities to revise their writing after debating and developed awareness of the usefulness of critique from peers. Given the development in oral argumentative practices and the quality of written arguments over time, this study indicates that students' development of oral and written argumentative practices is positively related to each other. This study suggests that argumentative practices should be framed through both a social and epistemic understanding of argument-utilizing talk and writing as vehicles to create norms of these complex practices.

  14. Estimating the Effective Permittivity for Reconstructing Accurate Microwave-Radar Images

    Science.gov (United States)

    Lavoie, Benjamin R.; Okoniewski, Michal; Fear, Elise C.

    2016-01-01

    We present preliminary results from a method for estimating the optimal effective permittivity for reconstructing microwave-radar images. Using knowledge of how microwave-radar images are formed, we identify characteristics that are typical of good images, and define a fitness function to measure the relative image quality. We build a polynomial interpolant of the fitness function in order to identify the most likely permittivity values of the tissue. To make the estimation process more efficient, the polynomial interpolant is constructed using a locally and dimensionally adaptive sampling method that is a novel combination of stochastic collocation and polynomial chaos. Examples, using a series of simulated, experimental and patient data collected using the Tissue Sensing Adaptive Radar system, which is under development at the University of Calgary, are presented. These examples show how, using our method, accurate images can be reconstructed starting with only a broad estimate of the permittivity range. PMID:27611785

  15. Gain assisted harmonic generation in near-zero permittivity metamaterials made of plasmonic nanoshells

    CERN Document Server

    Vincenti, Maria Antonietta; de Ceglia, Domenico; Capolino, Filippo; Scalora, Michael

    2012-01-01

    We investigate enhanced harmonic generation processes in gain-assisted, near-zero permittivity metamaterials composed of spherical plasmonic nanoshells. We report the presence of narrow-band features in transmission, reflection and absorption induced by the presence of an active material inside the core of the nanoshells. The damping-compensation mechanism used to achieve the near-zero effective permittivity condition also induces a significant increase in field localization and strength and, consequently, enhancement of linear absorption. When only metal nonlinearities are considered, second and third harmonic generation efficiencies obtained by probing the structure in the vicinity of the near-zero permittivity condition approach values as high as for irradiance value as low as . These results clearly demonstrate that a relatively straightforward path now exists to the development of exotic and extreme nonlinear optical phenomena in the KW/cm2 range

  16. Two-peak feature of the permittivity spectra of ferromagnetic microwire/rubber composites

    Science.gov (United States)

    Qin, F. X.; Quéré, Y.; Brosseau, C.; Wang, H.; Liu, J. S.; Sun, J. F.; Peng, H. X.

    2013-03-01

    The effective permittivity of CoFeSiB microwire/rubber composites is investigated in the microwave range of frequencies. As the frequency is varied between 0.3 and 6 GHz with or without magnetic field excitation, we identify a two-peak structure of the permittivity spectra. This spectral feature may be attributed to a core-shell structure of the microwires. That is, a core amorphous phase which is surrounded by a small amount of crystalline nanoshell. High-resolution transmission electron microscopy provides a direct means to detect the crystalline nanoshell. Electromagnetic simulations show that Drude-Lorentz's model of dispersion can describe the effective permittivity quite well in this range of frequencies.

  17. Multiphase permittivity imaging using absolute value electrical capacitance tomography data and a level set algorithm.

    Science.gov (United States)

    Al Hosani, E; Soleimani, M

    2016-06-28

    Multiphase flow imaging is a very challenging and critical topic in industrial process tomography. In this article, simulation and experimental results of reconstructing the permittivity profile of multiphase material from data collected in electrical capacitance tomography (ECT) are presented. A multiphase narrowband level set algorithm is developed to reconstruct the interfaces between three- or four-phase permittivity values. The level set algorithm is capable of imaging multiphase permittivity by using one set of ECT measurement data, so-called absolute value ECT reconstruction, and this is tested with high-contrast and low-contrast multiphase data. Simulation and experimental results showed the superiority of this algorithm over classical pixel-based image reconstruction methods. The multiphase level set algorithm and absolute ECT reconstruction are presented for the first time, to the best of our knowledge, in this paper and critically evaluated. This article is part of the themed issue 'Supersensing through industrial process tomography'. © 2016 The Author(s).

  18. On the Huygens principle for bianisotropic mediums with symmetric permittivity and permeability dyadics

    Science.gov (United States)

    Faryad, Muhammad; Lakhtakia, Akhlesh

    2017-02-01

    Mathematical statements of the Huygens principle relate the electric and magnetic field phasors at an arbitrary location in a source-free region enclosed by a surface to the tangential components of the electric and magnetic field phasors over that surface, via the dyadic Green functions applicable to the linear homogeneous medium occupying that region. We have mathematically formulated the Huygens principle for the electric and magnetic field phasors when the permittivity and permeability dyadics of the medium are symmetric, the symmetric parts of the two magnetoelectric dyadics of the medium are negative of each other, and both magnetoelectric dyadics also contain anti-symmetric terms. We have also formulated the Huygens principle for the electric (resp. magnetic) field phasor in a medium whose permittivity (resp. permeability) is scalar, the permeability (resp. permittivity) is symmetric, the symmetric parts of the two magnetoelectric dyadics reduce to dissimilar scalars, and anti-symmetric parts of the two magnetoelectric dyadics are identical.

  19. Determination of permittivity of pulses and cereals using metamaterial split ring resonator

    Science.gov (United States)

    Chakyar, Sreedevi P.; Sikha Simon, K.; Murali, Aathira; Shanto T., A.; Andrews, Jolly; Joseph V., P.

    2017-06-01

    Relative permittivity of wide variety of pulses and cereals are precisely determined with the help of metamaterial Split Ring Resonator (SRR) operating at microwave frequencies using a simple extraction procedure. The unknown permittivity of food samples in powder form are evaluated from a calibration curve drawn between the dielectric constant of some standard samples and LC resonant frequency of SRR test probe with the sample placed over it. The experimental setup consists of SRR test probe arranged between transmitting and receiving probes connected to a vector network analyzer. Unknown relative permittivity of the sample is obtained by placing it on the SRR surface and is evaluated from the calibration curve which is found to be in good agreement with the expected standard values. The possible applications of this sensitive and easy technique are analyzed in the field of food preservation, quality checking, adulteration etc.

  20. Gain assisted nanocomposite multilayers with near zero permittivity modulus at visible frequencies

    CERN Document Server

    Rizza, Carlo; Ciattoni, Alessandro

    2011-01-01

    We have fabricated a layered nano-composite by alternating metal and gain medium layers, the gain dielectric consisting of a polymer incorporating optically pumped dye molecules. Exploiting an improved version of the effective medium theory, we have chosen the layers thicknesses for achieving a very small value of the real part of the permittivity epsilon_\\| (parallel to the layers plane) at a prescribed visible wavelength. From standard reflection-transmission experiments on the optically pumped sample we show that, at a visible wavelength, both the real and the imaginary parts of the permittivity epsilon_\\ attain very small values and we measure | \\epsilon_\\| | = 0.04 at lambda = 604 nm, amounting to a 21.5-percent decrease of the minimum | \\epsilon_\\| | in the absence of optical pumping. Our investigation thus proves that a medium with a dielectric permittivity with very small modulus, a key condition which should provide efficient subwavelength optical steering, can be actually synthesized.

  1. A Complex Permittivity Based Sensor for the Electrical Characterization of High-Voltage Transformer Oils

    Directory of Open Access Journals (Sweden)

    Panayota Vassiliou

    2005-05-01

    Full Text Available This work investigates the use of a specially designed cylindrical metal cell, inorder to obtain complex permittivity and tanδ data of highly insulating High Voltage (HVtransformer oil samples. The data are obtained at a wide range of frequencies and operationtemperatures to demonstrate the polarization phenomena and the thermally stimulatedeffects. Such complex permittivity measurements may be utilized as a criterion for theservice life prediction of oil field electrical equipment (OFEE. Therefore, by one set ofmeasurements on a small oil volume, data may be provided on the impending termination,or continuation of the transformer oil service life. The oil incorporating cell, attached to theappropriate measuring units, could be described as a complex permittivity sensor. In thiswork, the acquired dielectric data from a great number of operating distribution networkpower transformers were correlated to corresponding physicochemical ones to demonstratethe future potential employment of the proposed measuring technique.

  2. The Impact of Physical Attractiveness and Trait Argumentativeness as Predictors of Responses to an Argumentative Situation.

    Science.gov (United States)

    Rancer, Andrew S.; Infante, Dominic A.

    A study examined the influence of physical attractiveness and trait argumentativeness as predictors of responses to an argumentative situation. Subjects, 152 college students identified as either high or low in trait argumentativeness, were randomly assigned to one of two treatment conditions: attractive or unattractive anticipated adversary. A…

  3. Using the Cognitive Apprenticeship Web-Based Argumentation System to Improve Argumentation Instruction

    Science.gov (United States)

    Tsai, Chun-Yen; Jack, Brady Michael; Huang, Tai-Chu; Yang, Jin-Tan

    2012-01-01

    This study investigated how the instruction of argumentation skills could be promoted by using an online argumentation system. This system entitled "Cognitive Apprenticeship Web-based Argumentation" (CAWA) system was based on cognitive apprenticeship model. One hundred eighty-nine fifth grade students took part in this study. A quasi-experimental…

  4. The analysis and evaluation of legal argumentation: approaches from legal theory and argumentation theory

    NARCIS (Netherlands)

    Feteris, E.; Kloosterhuis, H.

    2009-01-01

    In the past thirty years legal argumentation has become an important interdisciplinary field of interest. The study of legal argumentation draws its data, assumptions and methods from disciplines such as legal theory, legal philosophy, logic, argumentation theory, rhetoric, linguistics, literary the

  5. Argument z důsledku a jeho varianty (Argument from Consequences and its variants

    Directory of Open Access Journals (Sweden)

    Martina Juříková

    2016-03-01

    Full Text Available The article examines the use and evaluation of the argument from consequences, its historical origins since Aristotle through Blaise Pascal, David Hume until the inclusion of this argument into the textbooks of modern logic. The article also recapitulates current evaluation of this argument by Douglas Walton and along with Walton presents its two variants and criteria for evaluating their validity.

  6. Argumentation Analysis——A discourse Approach

    Institute of Scientific and Technical Information of China (English)

    张海燕

    2012-01-01

      Argumentation is a special kind of discourse. It had its own special type of structure、reasoning mode、cohesion and coherence、rhetorical devices. In this dissertation, the writer tries to discuss how to analyze an argumentation from a discoursal view. Also an example is given to support her idea.

  7. A general account of argumentation with preferences

    NARCIS (Netherlands)

    Modgil, Sanjay; Prakken, Henry

    2013-01-01

    This paper builds on the recent ASPIC(+) formalism, to develop a general framework for argumentation with preferences. We motivate a revised definition of conflict free sets of arguments, adapt ASPIC(+) to accommodate a broader range of instantiating logics, and show that under some assumptions, the

  8. Identifying Kinds of Reasoning in Collective Argumentation

    Science.gov (United States)

    Conner, AnnaMarie; Singletary, Laura M.; Smith, Ryan C.; Wagner, Patty Anne; Francisco, Richard T.

    2014-01-01

    We combine Peirce's rule, case, and result with Toulmin's data, claim, and warrant to differentiate between deductive, inductive, abductive, and analogical reasoning within collective argumentation. In this theoretical article, we illustrate these kinds of reasoning in episodes of collective argumentation using examples from one…

  9. Constructing validity arguments for test combinations

    NARCIS (Netherlands)

    Wools, Saskia; Eggen, Theo J.H.M.; Béguin, Anton

    2016-01-01

    The argument-based approach to validation has been widely adopted in validation theory. However, this approach aims to validate the intended interpretation and use of a single test or assessment. This article proposes an extension of the argument-based approach for validation of multiple tests. This

  10. Formalising arguments about the burden of persuasion.

    NARCIS (Netherlands)

    Prakken, H.; Sartor, G.

    2007-01-01

    This paper presents an argument-based logic for reasoning about allocations of the burden of persuasion. The logic extends the system of Prakken (2001), which in turn modified the system of Prakken & Sartor (1996) with the possibility to distribute the burden of proof over both sides in an argument

  11. AVER : Argument visualization for evidential reasoning

    NARCIS (Netherlands)

    Braak, S.W. van den; Vreeswijk, G.A.W.

    2006-01-01

    This paper reports on the ongoing development of a collaborative, webbased application for argument visualization named AVER (Argument Visualization for Evidential Reasoning). It is targeted at police officers who may use it to express their reasoning about a case based on evidence. AVER provides an

  12. Design Argumentation in Academic Design Education

    DEFF Research Database (Denmark)

    Dalsgaard, Peter; Dindler, Christian; Fritsch, Jonas

    2013-01-01

    We explore design argumentation as a resource when teaching interaction design in a university setting. We propose that design argumentation can help bridge between practice-based design education and theoretical issues from university curricula. In this paper, we outline the idea of design argum...

  13. English 450: Theories and Methods of Argument

    Science.gov (United States)

    Jones, Rebecca

    2008-01-01

    This article presents a course design of English 450: Theories and Methods of Argument. The course is an upper level course in the Writing concentration of B. A. in English and American Language and Literature at the University of Tennessee, Chattanooga, a metropolitan university in the South. At the 400 level, Theories and Methods of Argument is…

  14. The Performance of Literature as Argument.

    Science.gov (United States)

    Hershey, Lewis

    1988-01-01

    Reviews scholarship on the interdependence of rhetoric and poetic language, and proposes a performance as argument model for the oral interpretation of literature. Relates the model to current work on the relationship of narrative to argument and suggests benefits gained from its adoption. (SR)

  15. Generate an Argument: An Instructional Model

    Science.gov (United States)

    Sampson, Victor; Grooms, Jonathon

    2010-01-01

    The Generate an Argument instructional model was designed to engage students in scientific argumentation. By using this model, students develop complex reasoning and critical-thinking skills, understand the nature and development of scientific knowledge, and improve their communication skills (Duschl and Osborne 2002). This article describes the…

  16. Design Argumentation in Academic Design Education

    DEFF Research Database (Denmark)

    Dalsgaard, Peter; Dindler, Christian; Fritsch, Jonas

    2013-01-01

    We explore design argumentation as a resource when teaching interaction design in a university setting. We propose that design argumentation can help bridge between practice-based design education and theoretical issues from university curricula. In this paper, we outline the idea of design argum...

  17. The Fine-Tuning Argument

    CERN Document Server

    Landsman, Klaas

    2015-01-01

    Our laws of nature and our cosmos appear to be delicately fine-tuned for life to emerge, in way that seems hard to attribute to chance. In view of this, some have taken the opportunity to revive the scholastic Argument from Design, whereas others have felt the need to explain this apparent fine-tuning of the clockwork of the Universe by proposing the existence of a `Multiverse'. We analyze this issue from a sober perspective. Having reviewed the literature and having added several observations of our own, we conclude that cosmic fine-tuning supports neither Design nor a Multiverse, since both of these fail at an explanatory level as well as in a more quantitative context of Bayesian confirmation theory (although there might be other reasons to believe in these ideas, to be found in religion and in inflation and/or string theory, respectively). In fact, fine-tuning and Design even seem to be at odds with each other, whereas the inference from fine-tuning to a Multiverse only works if the latter is underwritten...

  18. Vygotsky's Crisis: Argument, context, relevance.

    Science.gov (United States)

    Hyman, Ludmila

    2012-06-01

    Vygotsky's The Historical Significance of the Crisis in Psychology (1926-1927) is an important text in the history and philosophy of psychology that has only become available to scholars in 1982 in Russian, and in 1997 in English. The goal of this paper is to introduce Vygotsky's conception of psychology to a wider audience. I argue that Vygotsky's argument about the "crisis" in psychology and its resolution can be fully understood only in the context of his social and political thinking. Vygotsky shared the enthusiasm, widespread among Russian leftist intelligentsia in the 1920s, that Soviet society had launched an unprecedented social experiment: The socialist revolution opened the way for establishing social conditions that would let the individual flourish. For Vygotsky, this meant that "a new man" of the future would become "the first and only species in biology that would create itself." He envisioned psychology as a science that would serve this humanist teleology. I propose that The Crisis is relevant today insofar as it helps us define a fundamental problem: How can we systematically account for the development of knowledge in psychology? I evaluate how Vygotsky addresses this problem as a historian of the crisis. Copyright © 2011 Elsevier Ltd. All rights reserved.

  19. Nondestructive relative permittivity and loss tangent measurements using a split-cylinder resonator

    Science.gov (United States)

    Janezic, Michael Daniel

    To keep pace with the expanding wireless and electronics industries, manufacturers are developing innovative materials for improving system performance, and there is a critical need to accurately characterize the electrical properties of these new materials at microwave frequencies. To address this need, this thesis develops a nondestructive method for measuring the relative permittivity and loss tangent of dielectric substrates using a split-cylinder resonator. Three theoretical models for the split-cylinder resonator are derived using mode-matching, least-squares boundary residual, and Hankel-transform methods, from which one can calculate the relative permittivity and loss tangent of a dielectric substrate from measurements of the split-cylinder resonator's TE0np resonant frequency and quality factor. Each of these models has several advantages over previously published models. First, the accuracy of the relative permittivity measurement is increased because each model accurately models the fringing fields that extend beyond the cylindrical-cavity sections. Second, to increase the accuracy of the loss tangent measurement, each model accurately separates the conductive metal losses of the split-cylinder resonator from the dielectric losses of the substrate. Finally, in contrast to previous models for the split-cylinder resonator that use only the TE011 resonant mode, each of the new models include the higher-order TE0np resonant modes, thereby broadening the frequency range over which one can make relative permittivity and loss tangent measurements. In a comparison of the three models, the mode-matching method was found to be superior on the basis of measurement accuracy and computational speed. Relative permittivity and loss tangent measurements for several dielectric materials are performed using a split-cylinder resonator and are in good agreement with measurements made using a circular-cylindrical cavity, split-post resonator, and dielectric post resonator

  20. The Determinants of Money Arguments between Spouses

    Directory of Open Access Journals (Sweden)

    Dorothy B. Durband

    2010-10-01

    Full Text Available A commonly held view is that arguments about money are associated with marital problems, but relatively little is known about the nature of arguing about money within marriage. Using data from the National Longitudinal Survey of Youth 1979 (NLSY79, this study uses a collective bargaining approach to examine the role of money arguments in marriage. The sample (N = 1,371 consists of married women. A collective bargaining framework provides a context for understanding money arguments within the marital relationship. Results indicate that costly communication is the dominant predictor of money arguments, followed by level and proportion of wife’s income, and household net worth. Because results suggest that both communication and financial resources are important components to understanding money arguments within marriage, a combination of professionals trained in marital therapy and/or financial planning is required for couples interested in seeking assistance to increase their satisfaction and/or avoid divorce.

  1. Similarity Arguments in the Genetic Modification Debate

    DEFF Research Database (Denmark)

    Christiansen, Andreas

    2017-01-01

    In the ethical debate on genetic modification (GM), it is common to encounter the claim that some anti-GM argument would also apply an established, ethically accepted technology, and that the anti-GM argument is therefore unsuccessful. The paper discusses whether this argumentative strategy...... transferability of reasons from one case to another; and (iii) it runs the risk of equivocations, especially in cases where the anti-genetic-modification argument relies on gradable features. The paper then shows how these issues play out in three specific Similarity Arguments that can be found in the literature....... Finally, the paper discusses what conclusions we can draw from the fact that genetic modification and established technologies are similar for the ethical status of genetic modification....

  2. Permittivity and permeability determination for high index specimens using partially filled shorted rectangular waveguides

    CERN Document Server

    Scott, Mark M; Bean, Jeffrey A; Allen, Kenneth W

    2016-01-01

    A method for determining the permittivity and permeability for specimens with high refractive index and variable shape is investigated. The method extracts the permeability and permittivity tensor elements from reflection measurements made with a partially-filled shorted rectangular waveguide on an electrically small specimen. Measurements are performed for two isotropic, heavily loaded coaxial magnetic composites. Supporting measurements from a stripline cavity and coaxial airline are used to validate the method. The results demonstrate the methods ability to handle frequency dispersive and high index materials.

  3. A simple method for reducing inevitable dielectric loss in high-permittivity dielectric elastomers

    DEFF Research Database (Denmark)

    Madsen, Frederikke Bahrt; Yu, Liyun; Mazurek, Piotr Stanislaw;

    2016-01-01

    Commercial viability of dielectric elastomers (DEs) is currently limited by a few obstacles, including high driving voltages (in the kV range). Driving voltage can be lowered by either decreasing the Young's modulus or increasing the dielectric permittivity of silicone elastomers, or a combinatio...... also decreased the dielectric losses of an elastomer containing dielectric permittivity-enhancing TiO2 fillers. Commercially available chloropropyl-functional silicone oil thus constitutes a facile method for improved silicone DEs, with very low dielectric losses....

  4. Ionic conductivity and dielectric permittivity of polymer electrolyte plasticized with polyethylene glycol

    Science.gov (United States)

    Das, S.; Ghosh, A.

    2016-05-01

    We have studied ionic conductivity and dielectric permittivity of PEO-LiClO4 solid polymer electrolyte plasticized with polyethylene glycol (PEG). The temperature dependence of the ionic conductivity has been well interpreted using Vogel-Tamman-Fulcher equation. The maximum dielectric constant is observed for 30 wt. % of PEG content. To get further insights into the ion dynamics, the complex dielectric permittivity has been studied with Havriliak-Negami function. The variation of relaxation time with inverse temperature obtained from HN formalism follows VTF nature.

  5. Non-reflecting permittivity profiles and the spatial Kramers-Kronig relations

    CERN Document Server

    Horsley, S A R; La Rocca, G C

    2015-01-01

    We show that if the permittivity profile of a planar dielectric medium is an analytic function in the upper (lower) half complex position plane then it won't reflect radiation from the left (right), whatever the angle of incidence. Consequently, using the spatial Kramers-Kronig relations one can derive a real part of a permittivity profile from some given imaginary part (or vice versa), such that the reflection is guaranteed to be zero. This result is valid for both scalar and vector wave theories, and may have relevance for efficiently absorbing radiation, or reducing reflection from bodies.

  6. A Rectangular Split Ring Double Negative Metamaterial having Simultaneous Negative Permittivity and Permeability

    Directory of Open Access Journals (Sweden)

    Muhammad Waqas

    2014-06-01

    Full Text Available The scope of this paper is to design and simulate a novel structure having simultaneous negative permittivity and permeability so called double negative metamaterial or left handed material. The DNG structure consists of five rectangular split ring resonators on one side of dielectric medium and a couple of wires on other side. The complex permittivity, permeability and refractive index are determined from simulated Scattering parameters using direct retrieval method. Simulations of DNG structure are carried out using CST MWS. MATLAB is used for verification of negative values of structure's parameter.

  7. Lagrange-type modeling of continuous dielectric permittivity variation in double-higher-order volume integral equation method

    Science.gov (United States)

    Chobanyan, E.; Ilić, M. M.; Notaroš, B. M.

    2015-05-01

    A novel double-higher-order entire-domain volume integral equation (VIE) technique for efficient analysis of electromagnetic structures with continuously inhomogeneous dielectric materials is presented. The technique takes advantage of large curved hexahedral discretization elements—enabled by double-higher-order modeling (higher-order modeling of both the geometry and the current)—in applications involving highly inhomogeneous dielectric bodies. Lagrange-type modeling of an arbitrary continuous variation of the equivalent complex permittivity of the dielectric throughout each VIE geometrical element is implemented, in place of piecewise homogeneous approximate models of the inhomogeneous structures. The technique combines the features of the previous double-higher-order piecewise homogeneous VIE method and continuously inhomogeneous finite element method (FEM). This appears to be the first implementation and demonstration of a VIE method with double-higher-order discretization elements and conformal modeling of inhomogeneous dielectric materials embedded within elements that are also higher (arbitrary) order (with arbitrary material-representation orders within each curved and large VIE element). The new technique is validated and evaluated by comparisons with a continuously inhomogeneous double-higher-order FEM technique, a piecewise homogeneous version of the double-higher-order VIE technique, and a commercial piecewise homogeneous FEM code. The examples include two real-world applications involving continuously inhomogeneous permittivity profiles: scattering from an egg-shaped melting hailstone and near-field analysis of a Luneburg lens, illuminated by a corrugated horn antenna. The results show that the new technique is more efficient and ensures considerable reductions in the number of unknowns and computational time when compared to the three alternative approaches.

  8. Anthropic-principle arguments against steady-state cosmological theories

    Energy Technology Data Exchange (ETDEWEB)

    Tipler, F.J. (Tulane Univ., New Orleans, LA (USA))

    1982-04-01

    Steady-state theories are very difficult to rule out on observational grounds, particularly if they are adjusted to contain a three-degree isotropic thermal-background radiation. However, anthropic-principle arguments can be used to rule out virtually any cosmological theory which has the universe stationary in the large. For example, anthropic considerations show that the perfect cosmological principle is self-contradictory.

  9. Revisiting the argument from fetal potential

    Directory of Open Access Journals (Sweden)

    Manninen Bertha

    2007-05-01

    Full Text Available Abstract One of the most famous, and most derided, arguments against the morality of abortion is the argument from potential, which maintains that the fetus' potential to become a person and enjoy the valuable life common to persons, entails that its destruction is prima facie morally impermissible. In this paper, I will revisit and offer a defense of the argument from potential. First, I will criticize the classical arguments proffered against the importance of fetal potential, specifically the arguments put forth by philosophers Peter Singer and David Boonin, by carefully unpacking the claims made in these arguments and illustrating why they are flawed. Secondly, I will maintain that fetal potential is morally relevant when it comes to the morality of abortion, but that it must be accorded a proper place in the argument. This proper place, however, cannot be found until we first answer a very important and complex question: we must first address the issue of personal identity, and when the fetus becomes the type of being who is relevantly identical to a future person. I will illustrate why the question of fetal potential can only be meaningfully addressed after we have first answered the question of personal identity and how it relates to the human fetus.

  10. Simultaneous measurement of hysteresis in capillary pressure and electric permittivity for multiphase flow through porous media

    NARCIS (Netherlands)

    Plug, W.J.; Slob, E.C.; Bruining, J.; Moreno Tirado, L.M.

    2007-01-01

    We present a tool that simultaneously measures the complex permittivity and the capillary pressure characteristics for multiphase flow. The sample holder is a parallel plate capacitor. A precision component analyzer is used to measure the impedance amplitude and phase angle as a function of frequenc

  11. Optimising a modified free-space permittivity characterisation method for civil engineering applications

    Science.gov (United States)

    Muller, Wayne; Scheuermann, Alexander

    2016-04-01

    Measuring the electrical permittivity of civil engineering materials is important for a range of ground penetrating radar (GPR) and pavement moisture measurement applications. Compacted unbound granular (UBG) pavement materials present a number of preparation and measurement challenges using conventional characterisation techniques. As an alternative to these methods, a modified free-space (MFS) characterisation approach has previously been investigated. This paper describes recent work to optimise and validate the MFS technique. The research included finite difference time domain (FDTD) modelling to better understand the nature of wave propagation within material samples and the test apparatus. This research led to improvements in the test approach and optimisation of sample sizes. The influence of antenna spacing and sample thickness on the permittivity results was investigated by a series of experiments separating antennas and measuring samples of nylon and water. Permittivity measurements of samples of nylon and water approximately 100 mm and 170 mm thick were also compared, showing consistent results. These measurements also agreed well with surface probe measurements of the nylon sample and literature values for water. The results indicate permittivity estimates of acceptable accuracy can be obtained using the proposed approach, apparatus and sample sizes.

  12. How the relative permittivity of solar cell materials influences solar cell performance

    DEFF Research Database (Denmark)

    Crovetto, Andrea; Huss-Hansen, Mathias K.; Hansen, Ole

    2017-01-01

    The relative permittivity of the materials constituting heterojunction solar cells is usually not considered as a design parameter when searching for novel combinations of heterojunction materials. In this work, we investigate the validity of such an approach. Specifically, we show the effect of ...

  13. Profiles of relative permittivity and electrical conductivity from unsaturated soil water content models

    Directory of Open Access Journals (Sweden)

    Roberta Porretta

    2016-07-01

    Full Text Available A mathematical model of water diffusion in the vadose zone has been implemented for different types of soil textures in order to determine the soil water content (SWC profiles in dependence of depth and time. From these profiles, obtained for different soils, we derived the characteristic electrical parameters, such as relative permittivity (epsilonr and electrical conductivity (sigma, and their variation in time, employing empirical relations available in the scientific literature. The simulation through mathematical models has been performed taking into account different types of soils characterized by the percentage composition of sand, clay and silt in the textural triangle, which provides some physical and chemical properties that affect the water retention in the soil. The resulting simulated profiles of SWC and consequently permittivity and conductivity profiles, span over a certain range of values suggesting the best techniques and the limits in geophysical investigation. Moreover this a-prior knowledge helps in the elaboration and interpretation of permittivity and conductivity data obtained by the measurements. Permittivity and conductivity profiles are particularly useful in some environmental applications when the soil textures are (or supposed to be known as in the typical case of landfill leachate dispersion. Since the soil textures beneath or nearby a disposal waste are characterized by a SWC, the values of (epsilonr and (sigma at various depth can be directly inferred.

  14. Coaxial Sensors For Broad-Band Complex Permittivity Measurements of Petroleum Fluids

    Energy Technology Data Exchange (ETDEWEB)

    Folgeroe, K.

    1996-12-31

    This doctoral thesis verifies that dielectric spectroscopy and microwave permittivity measurements can be used to characterize petroleum liquids. It concentrates on developing sensors for three potential industrial applications: quality characterization of crude oil and petroleum fractions, monitoring of gas-hydrate formation in water-in-oil emulsions, and determination of water-content in thin liquid layers. The development of a permittivity measurement system for crude oil and petroleum fractions is described. As black oils have low dielectric constant and loss, the system must be very sensitive in order to measure the dielectric spectra and to distinguish oils of different permittivity. Such a system was achieved by combining impedance and scattering parameter measurements with appropriate permittivity calculation methods. The frequency range from 10 kHz to 6 GHz was found convenient for observing the main dispersion of the oils. All the oils had dielectric constants between 2.1 and 2.9 and dielectric loss below 0.01. The oils studied were samples of the feedstock for the cracker and coke processes at a petroleum refinery. This verifies that dielectric spectroscopy is a potential technique for on-line quality monitoring of the feedstock at petroleum refineries. Gas hydrates may cause major problems like clogging of pipelines. Dielectric spectroscopy is proposed as a means of monitoring the formation of gas hydrates in emulsions. It is found that open-ended coaxial probes fulfill the sensitivity requirements for such sensors. 312 refs., 87 figs., 20 tabs.

  15. Study on the Microwave Permittivity of Single-Walled Carbon Nanotube

    Science.gov (United States)

    Liu, Xiaolai; Zhao, Donglin

    2009-01-01

    In this article, we studied the microwave permittivity of the complex of the single-walled carbon nanotube and paraffin in 2-18GHz. In the range, the dielectric loss of single-walled carbon nanotube is higher, and the real part and the imaginary part of the dielectric constant decrease with the increase of frequency, and the dielectric constant…

  16. Novel encapsulation technique for incorporation of high permittivity fillers into silicone elastomers

    DEFF Research Database (Denmark)

    Mazurek, Piotr Stanislaw; Hvilsted, Søren; Skov, Anne Ladegaard

    2014-01-01

    as for the traditionally applied thermoplastic encapsulation. The properties of the elastomers are investigated as function of the filler content and type. The dielectric permittivity, dielectric loss, conductivity, storage modulus as well as viscous loss are compared to elastomers with the same amounts of high...

  17. Effect of swift heavy Kr ions on complex permittivity of silicon PIN diode

    Science.gov (United States)

    Li, Yun; Su, Ping; Yang, Zhimei; Ma, Yao; Gong, Min

    2016-12-01

    The complex permittivity has been researched on silicon PIN diodes irradiated by 2150 MeV heavy Kr ions in this article. The difference of complex permittivity spectra from 1 to 10^7 Hz between irradiated and unirradiated were observed and discussed. The current-voltage (I-V) and capacitance-voltage (C-V) characteristics were measured at room temperature (300 K) to study the change of electrical properties in diode after irradiation. Deep level transient spectroscopy (DLTS) was used to investigate damages caused by 2150 MeV heavy Kr ions in diode. Two extra electron traps were observed, which were located at EC-0.31 eV and EC-0.17 eV. It indicated that new defects have been formed in PIN diode during irradiation. A comparison of the results illustrated that not only the carrier density but also the recombination of electron-hole pair have important influences on the properties of complex permittivity. These results offer a further indication of the mechanism about the complex permittivity property of semiconductor device, which could help to make the applications for the semiconductor device controlled by electric signals come true in the fields of optoelectronic integrated circuits, plasma antenna and so on.

  18. Enhancing relative permittivity by incorporating PDMS-PEG multi block copolymers in binary polymer blends

    DEFF Research Database (Denmark)

    A Razak, Aliff Hisyam; Szabo, Peter; Skov, Anne Ladegaard

    a possibility for substantial improvement of properties such as high permittivity, stretchability and non-conductivity – if carefully designed. The objective is to synthesize PDMS-PEG multiblock copolymer assembling into discontinuous morphologies in PEG based on variation of volume fractions of PDMS...

  19. Kramers-Kronig relations for plasma-like permittivities and the Casimir force

    CERN Document Server

    Klimchitskaya, G L; Mostepanenko, V M

    2007-01-01

    The Kramers-Kronig relations are derived for the permittivity of the usual plasma model which neglects dissipation and of a generalized model which takes into account the interband transitions. The generalized plasma model is shown to be consistent with all precision experiments on the measurement of the Casimir force.

  20. Experimental study on size-dependency of effective permittivity of particle-gas mixture with agglomeration

    Institute of Scientific and Technical Information of China (English)

    Li Xiaomin; Xu Lijun; Li Songyun

    2007-01-01

    The effective medium approximation (EMA) theory is the basis of a capacitance sensor used for concentration measurement of a particulate solid flow, its measurement result is independent on particle size. In existence of particle agglomeration or aggradation, however, it is found that the effective permittivity of a gas/solid mixture is dependent on particle size. In this paper, a parallel plate, differential capacitance sensor is utilized to investigate the influence of particle size on the effective permittivity of the mixture in such a case. Static experiments using three materials including glass, limestone and quartz particles were carried out in an off-line manner. The volume fraction of particles being tested ranged from 20×10-6 to 600×10-6, while the particle size was between 3 and 100 μm. Experimental results show that the effective permittivity of a particle-gas mixture with particle agglomeration is larger than that predicted by EMA and the smaller the particle size, the larger the effective permittivity. The experiment process and analysis results are discussed in detail in the paper.

  1. The effect of filler on the temperature coefficient of the relative permittivity of PTFE/ceramic composites

    Science.gov (United States)

    Rajesh, S.; Murali, K. P.; Jantunen, H.; Ratheesh, R.

    2011-11-01

    High permittivity and low-loss ceramic fillers have been prepared by means of the solid state ceramic route. Ceramic-filled composites were prepared by the Sigma Mixing, Extrusion, Calendering, which was followed by the Hot pressing (SMECH) process. The microwave dielectric properties of the composites were studied using X-band waveguide cavity perturbation technique. The temperature coefficient of the relative permittivity of the composites was investigated in the 0-100 °C temperature range using a hot and cold chamber coupled with an impedance analyzer. The temperature coefficient of the relative permittivity of the composites showed strong dependence on the temperature coefficient of the relative permittivity of the filler material. In the present study, a high-permittivity polymer/ceramic composite, having τεr ∼63 ppm/K, has been realized. This composite is suitable for outdoor wireless applications.

  2. Integrated argument-based inquiry with multiple representation approach to promote scientific argumentation skill

    Science.gov (United States)

    Suminar, Iin; Muslim, Liliawati, Winny

    2017-05-01

    The purpose of this research was to identify student's written argument embedded in scientific inqury investigation and argumentation skill using integrated argument-based inquiry with multiple representation approach. This research was using quasi experimental method with the nonequivalent pretest-posttest control group design. Sample ot this research was 10th grade students at one of High School in Bandung using two classes, they were 26 students of experiment class and 26 students of control class. Experiment class using integrated argument-based inquiry with multiple representation approach, while control class using argument-based inquiry. This study was using argumentation worksheet and argumentation test. Argumentation worksheet encouraged students to formulate research questions, design experiment, observe experiment and explain the data as evidence, construct claim, warrant, embedded multiple modus representation and reflection. Argumentation testinclude problem which asks students to explain evidence, warrants, and backings support of each claim. The result of this research show experiment class students's argumentation skill performed better than control class students that of experiment class was 0.47 and control class was 0.31. The results of unequal variance t-test for independent means show that students'sargumentationskill of experiment class performed better significantly than students'sargumentationskill of control class.

  3. Finite-element method for calculation of the effective permittivity of random inhomogeneous media

    Science.gov (United States)

    Myroshnychenko, Viktor; Brosseau, Christian

    2005-01-01

    The challenge of designing new solid-state materials from calculations performed with the help of computers applied to models of spatial randomness has attracted an increasing amount of interest in recent years. In particular, dispersions of particles in a host matrix are scientifically and technologically important for a variety of reasons. Herein, we report our development of an efficient computer code to calculate the effective (bulk) permittivity of two-phase disordered composite media consisting of hard circular disks made of a lossless dielectric (permittivity ɛ2 ) randomly placed in a plane made of a lossless homogeneous dielectric (permittivity ɛ1 ) at different surface fractions. Specifically, the method is based on (i) a finite-element description of composites in which both the host and the randomly distributed inclusions are isotropic phases, and (ii) an ordinary Monte Carlo sampling. Periodic boundary conditions are employed throughout the simulation and various numbers of disks have been considered in the calculations. From this systematic study, we show how the number of Monte Carlo steps needed to achieve equilibrated distributions of disks increases monotonically with the surface fraction. Furthermore, a detailed study is made of the dependence of the results on a minimum separation distance between disks. Numerical examples are presented to connect the macroscopic property such as the effective permittivity to microstructural characteristics such as the mean coordination number and radial distribution function. In addition, several approximate effective medium theories, exact bounds, exact results for two-dimensional regular arrays, and the exact dilute limit are used to test and validate the finite-element algorithm. Numerical results indicate that the fourth-order bounds provide an excellent estimate of the effective permittivity for a wide range of surface fractions, in accordance with the fact that the bounds become progressively narrower as

  4. Chronology violation and the Cosmological Argument

    CERN Document Server

    Romero, G E

    2003-01-01

    The Kalam Cosmological Argument is perhaps the most solid and widly discussed argument for a caused creation of the universe. The usual objections to the argument mainly focus on the second premise. In this paper we discuss the dependency of the first premise on the topological structure of the space-time manifold adopted for the underlying cosmological model. It is shown that in chronology-violating space-times the first premise is also violated. The chronology-violation, in turn, requires a massive violation of the so-called energy conditions which could have observational effects that are briefly discussed here. Hence, astronomical observations could be relevant for the validity of the metaphysical argument. In this sense, it is possible to talk of "observational theology".

  5. Acting parentally: an argument against sex selection.

    Science.gov (United States)

    McDougall, R

    2005-10-01

    The Human Fertilisation and Embryology Authority's (HFEA) recent restrictive recommendations on sex selection have highlighted the need for consideration of the plausibility of ethical arguments against sex selection. In this paper, the author suggests a parental virtues approach to some questions of reproductive ethics (including sex selection) as a superior alternative to an exclusively harm focused approach such as the procreative liberty framework. The author formulates a virtue ethics argument against sex selection based on the idea that acceptance is a character trait of the good parent. It is concluded that, because the argument presented posits a wrong in the sex selecting agent's action that is not a harm, the argument could not function as a justification of the HFEA's restrictive position in light of their explicit commitment to procreative liberty; it does, however, suggest that ethical approaches focused exclusively on harm fail to capture all the relevant moral considerations and thus that we should look beyond such approaches.

  6. PREFERRED ARGUMENT STRUCTURE IN MANDARIN CHILD LANGUAGE

    National Research Council Canada - National Science Library

    Chiung-chih Huang

    2012-01-01

    ...). The results showed that Mandarin child language conforms to the constraints of Preferred Argument Structure, but that it does not support the related hypothesis of an ergative structuring of discourse...

  7. The Turing Test and the Zombie Argument

    OpenAIRE

    Kostic, Daniel

    2004-01-01

    In this paper I shall try to put some implications concerning the Turing's test and the so-called Zombie arguments into the context of philosophy of mind. My intention is not to compose a review of relevant concepts, but to discuss central problems, which originate from the Turing's test - as a paradigm of computational theory of mind - with the arguments, which refute sustainability of this thesis. In the first section (Section I), I expose the ...

  8. Modeling argumentation based semantics using non-monotonic reasoning

    OpenAIRE

    2005-01-01

    Argumentation theory is an alternative style of formalizing non-monotonic reasoning. It seems, argumentation theory is a suitable framework for practical and uncertain reasoning, where arguments support conclusions. Dung's approach is an unifying framework which has played an influential role on argumentation research and Artificial Intelligence. Even though the success of the argumentation theory, it seems that argumentation theory is so far from being efficiently implemented like the logic ...

  9. Modalne argumenty teistyczne (Modal Theistic Arguments

    Directory of Open Access Journals (Sweden)

    Graham Oppy

    2011-06-01

    Full Text Available The aim of Oppy’s paper is to provide a general ground for rejecting all kinds of modal theistic arguments. The author claims that all such arguments are questionbegging – before proving the existence of God (defined as a being which exists in every possible world theistic modalist must assume it when choosing his account of logical space (no matter which modal theory it relies on: Lewis’ modal realism, ersatz modal realism, combinatorialism or fictionalism. Two concrete arguments, Plantinga’s ontological argument and Leftow’s cosmological argument, are examples given by Oppy – both have premises which justification must refer to a non-modal question “Does God actually exist?”, concerning the nature of logical space.Oppy rejects suggestion that problems with modal theistic arguments show that there is simply something wrong with our standard modal analyses in terms of possible worlds. According to Oppy, problems with higher-level judgments about the nature of logical space are problems with propositional attitudes, not with modality, andthey need an analysis distinct from the analysis of ground-level modal judgments.

  10. Evaluation of High Permittivity Glass Ceramics for Millimeter Wave Applications.

    Science.gov (United States)

    2014-09-26

    patterns were run from room temperature to 1200QCwith a heating rate of 100C/minute. Each of the glasses exhib.ited an endothermic peak...corresponding to a glass transition temperature of 760*C, and a large exothermic peak at 900°C, presumably corresponding to the crystallization of SrTi0 3...the SrTiO 3 , although definitive dielectric loss data supporting these proposed mechanisms were not presented. In this paper, low temperature

  11. The Nature of the Arguments for Creationism, Intelligent Design, and Evolution

    Science.gov (United States)

    Barnes, Ralph M.; Church, Rebecca A.; Draznin-Nagy, Samuel

    2017-03-01

    Seventy-two Internet documents promoting creationism, intelligent design (I.D.), or evolution were selected for analysis. The primary goal of each of the 72 documents was to present arguments for creationism, I.D., or evolution. We first identified all arguments in these documents. Each argument was then coded in terms of both argument type (appeal to authority, appeal to empirical evidence, appeal to reason, etc.) and argument topic (age of earth, mechanism of descent with modification, etc.). We then provided a quantitative summary of each argument type and topic for each of the three positions. Three clear patterns were revealed by the data. First, websites promoting evolution were characterized by a narrow focus on appeals to empirical evidence, whereas websites promoting creationism and I.D. were quite heterogeneous in regards to argument type. Second, websites promoting evolution relied primarily on a small number of empirical examples (e.g., fossils, biogeography, homology, etc.), while websites promoting creationism and I.D. used a far greater range of arguments. Finally, websites promoting evolution were narrowly focused on the topic of descent with modification. In contrast, websites promoting creationism tackled a broad range of topics, while websites promoting I.D. were narrowly focused on the issue of the existence of God. The current study provides a quantitative summary of a systematic content analysis of argument type and topic across a large number of frequently accessed websites dealing with origins. The analysis we have used may prove fruitful in identifying and understanding argumentation trends in scientific writing and pseudo-scientific writing.

  12. The Nature of the Arguments for Creationism, Intelligent Design, and Evolution

    Science.gov (United States)

    Barnes, Ralph M.; Church, Rebecca A.; Draznin-Nagy, Samuel

    2017-02-01

    Seventy-two Internet documents promoting creationism, intelligent design (I.D.), or evolution were selected for analysis. The primary goal of each of the 72 documents was to present arguments for creationism, I.D., or evolution. We first identified all arguments in these documents. Each argument was then coded in terms of both argument type (appeal to authority, appeal to empirical evidence, appeal to reason, etc.) and argument topic (age of earth, mechanism of descent with modification, etc.). We then provided a quantitative summary of each argument type and topic for each of the three positions. Three clear patterns were revealed by the data. First, websites promoting evolution were characterized by a narrow focus on appeals to empirical evidence, whereas websites promoting creationism and I.D. were quite heterogeneous in regards to argument type. Second, websites promoting evolution relied primarily on a small number of empirical examples (e.g., fossils, biogeography, homology, etc.), while websites promoting creationism and I.D. used a far greater range of arguments. Finally, websites promoting evolution were narrowly focused on the topic of descent with modification. In contrast, websites promoting creationism tackled a broad range of topics, while websites promoting I.D. were narrowly focused on the issue of the existence of God. The current study provides a quantitative summary of a systematic content analysis of argument type and topic across a large number of frequently accessed websites dealing with origins. The analysis we have used may prove fruitful in identifying and understanding argumentation trends in scientific writing and pseudo-scientific writing.

  13. An additional S-shaped structure for sensitivity improvement of coaxial probe for permittivity determination of low loss materials

    Science.gov (United States)

    Jiao, Xingmin; Jin, Wei; Yang, Xiaoqing

    2015-05-01

    Permittivity measurement of materials is important in microwave chemistry, microwave material processing and microwave heating. The open-ended coaxial line method is one of the most popular and effective means for permittivity measurement. However, the conventional coaxial probe has difficulty in distinguishing small permittivity variations for low loss media. In this paper an additional S-shaped structure is proposed for sensitivity improvement of a coaxial probe for permittivity determination of low loss materials at 2.45 GHz. The small permittivity variation can be distinguished due to field enhancement generated by the additional S-shaped structure. We studied the variation of reflection coefficient amplitude for three kinds of samples with different moisture content, within the probe at different insertion depths. We find that the conventional coaxial probe cannot distinguish small permittivity variations until the moisture content of materials reaches 3%. Meanwhile, the probe with the S-shaped structure can detect such small permittivity variations when the moisture content of samples changes by only 1%. The experimental results demonstrate that the new probe proposed in this paper is reliable and feasible.

  14. Cosmochemical implications of CONSERT permittivity characterization of 67P/C-G

    Science.gov (United States)

    Levasseur-Regourd, A.; Hérique, Alain; Kofman, Wlodek; Beck, Pierre; Bonal, Lydie; Buttarazzi, Ilaria; Heggy, Essam; Lasue, Jeremie; Quirico, Eric; Zine, Sonia

    2016-10-01

    Unique information about the internal structure of the nucleus of comet 67P/C-G was provided by the CONSERT bistatic radar on-board Rosetta and Philae [1]. Analysis of the propagation of its signal throughout the small lobe indicated that the real part of the permittivity at 90 MHz is of (1.27±0.05). The first interpretation of this value using dielectric properties of mixtures of dust and ices (H2O, CO2), led to the conclusion that the comet porosity ranges between 75-85%. In addition, the dust/ice ratio was found to range between 0.4-2.6 and the permittivity of dust (including 30% of porosity) was determined to be lower than 2.9.The dust permittivity estimate is now reduced by taking into account the updated values of nucleus density and of dust/ice ratio, in order of providing further insights into the nature of the constituents of comet 67P/C-G [2]. We adopt a systematic approach: i) determination of the dust permittivity as a function of the ice (I) to dust (D) and vacuum (V) volume fraction; ii) comparison with the permittivity of meteoritic, mineral and organic materials from literature and laboratory measurements; iii) test of several composition models of the nucleus, corresponding to cosmochemical end members of 67P/C-G. For each of these models the location in the ternary I/D/V diagram is calculated based on available dielectric measurements, and confronted to the locus of 67P/C-G. The number of compliant models is small and the cosmochemical implications of each are discussed [2]. An important fraction of carbonaceous material is required in the dust in order to match CONSERT permittivity observations, establishing that comets represent a massive carbon reservoir.Support from Centre National d'Études Spatiales (CNES, France) for this work, based on observations with CONSERT on board Rosetta, is acknowledged. The CONSERT instrument was designed, built and operated by IPAG, LATMOS and MPS and was financially supported by CNES, CNRS, UJF/UGA, DLR and MPS

  15. Enhancement and interplay of first- and second-order spatial dispersion in metamaterials with moderate-permittivity inclusions

    Science.gov (United States)

    Rizza, Carlo; Galdi, Vincenzo; Ciattoni, Alessandro

    2017-08-01

    We investigate a class of multilayered metamaterials characterized by moderate-permittivity inclusions and low average permittivity. Via first-principles calculations, we show that in such a scenario, first- and second-order spatial dispersions may exhibit a dramatic and nonresonant enhancement, and may become comparable with the local response. Their interplay gives access to a wealth of dispersion regimes encompassing additional extraordinary waves and topological phase transitions. In particular, we identify a configuration featuring bound and disconnected isofrequency contours. Since they do not rely on high-permittivity inclusions, our proposed metamaterials may constitute an attractive and technologically viable platform for engineering nonlocal effects in the optical range.

  16. Teaching science as argument: Prospective elementary teachers' knowledge

    Science.gov (United States)

    Barreto-Espino, Reizelie

    For the past two decades there has been increasing emphasis on argumentation in school science. In 2007, the National Research Council published a synthesis report that emphasizes the centrality of constructing, evaluating, and using scientific explanations. Participating in argumentation is seen as fundamental to children's science learning experiences. These new expectations increase challenges for elementary teachers since their understanding of and experiences with science are overwhelmingly inconsistent with teaching science as argument. These challenges are further amplified when dealing with prospective elementary teachers. The current study was guided by the following research questions: (1) What are the ways in which preservice elementary teachers appropriate components of "teaching science as argument" during their student teaching experience? (2) To what extent do components from prospective elementary teachers' reflections influence planning for science teaching? (3) What elements from the context influence preservice elementary teachers' attention to teaching science as argument? This study followed a multi-participant case study approach and analyses were informed by grounded theory. Three participants were selected from a larger cohort of prospective elementary teachers enrolled in an innovative Elementary Professional Development School (PDS) partnership at a large Northeast University. Cross-case analysis allowed for the development of five key assertions: (1) The presence of opportunities for interacting with phenomena and collecting first hand data helped participants increase their emphasis on evidence-based explanations. (2) Participants viewed science talks as an essential mechanism for engaging students in the construction of evidence-based explanations and as being fundamental to meaning-making. (3) Participants demonstrated attention to scientific subject matter during instruction rather than merely focusing on activities and/or inquiry

  17. Argumentation Ethics and The Philosophy of Freedom

    Directory of Open Access Journals (Sweden)

    Frank van Dun

    2009-03-01

    Full Text Available When H.-H. Hoppe claimed (in A Theory of Socialism and Capitalism, 1989 that the principles of libertarianism were argumentatively irrefutable, both the logical coherence and the relevance of his “argument from argumentation” were criticized. While occasionally some of these criticisms still crop up, this paper defends Hoppe’s claim against them from the vantage point of the author’s own work (in Dutch on the ethics of dialogue in the nineteen-seventies. It presents a more detailed and systematic presentation of the “argument from argumentation” than Hoppe had need for in the particular context of his book. It makes a distinction between arguments about principles and arguments about particular cases in which these principles may be invoked; and between the normative validity (as a matter of principle of certain presumptions and the fact that in particular cases these presumptions hold only in principle and can be refuted by the evidence pertaining to the cases.

  18. Electrical permittivity of Ni and NiZn ferrite-polymer composites

    Energy Technology Data Exchange (ETDEWEB)

    Razzitte, A.C. [Laboratorio de Fisicoquimica de Materiales Ceramicos Electronicos (LAFMACEL), Departamento de Quimica, Universidad de Buenos Aires, Paseo Colon 850, Capital Fedcral 1063, Buenos Aires (Argentina)]. E-mail: arazzit@fi.uba.ar; Fano, W.G. [Departamento de Electronica, Facultad.de Ingenieria, Universidad de Buenos Aires, Paseo Colon 850, Capital Fedcral 1063, Buenos Aires (Argentina); Jacobo, S.E. [Laboratorio de Fisicoquimica de Materiales Ceramicos Electronicos (LAFMACEL), Departamento de Quimica, Universidad de Buenos Aires, Paseo Colon 850, Capital Fedcral 1063, Buenos Aires (Argentina)

    2004-12-31

    Electrical properties of polymers, well known for their insulating properties, may be improved by adding various functional fillers. Polymer-ferrite composites have been a subject of recent extensive research. Electric properties of such composites depend on the size, shape and amount of added filler in general. When polymer-ferrite composites are particularly used as electromagnetic wave absorbers and EMI shielding materials, it is very important to explain the variation of permeability and permittivity in the measured frequency ranges. In this paper, acrylic-Ni ferrite composites and acrylic-NiZn ferrite composites were used. The effects of the weight fraction of ferrite on the frequency dispersion characteristics of the complex permittivity are studied.

  19. Negative-permittivity plasma generation in negative-permeability space with high-energy metamaterials

    Science.gov (United States)

    Sakai, Osamu; Nakamura, Yoshihiro; Iwai, Akinori; Iio, Satoshi

    2016-10-01

    Plasma generation by electromagnetic waves in negative-permeability space is analyzed using experimental results and theoretical models. Installation of negative-permeability metamaterials triggers drastic changes to the propagation of electromagnetic waves. Unlike usual cases in which permeability is  +1, negative permeability induces evanescent modes in a space without plasma. However, if permittivity becomes negative due to high-electron-density or overdense plasma, electromagnetic waves can propagate because negative-refractive-index states emerge. In this study, reviewing our previous experimental data, we study the underlying physical processes in plasma generation in terms of wave propagation and parameters of wave media. We confirm nonlinear (transition) processes in the phase of density evolution up to the negative permittivity state and negative-refractive-index states in the quasi-steady phase. We also note that such energetic metamaterials are built up when we use plasma, unlike conventional metamaterials composed of solid-state materials.

  20. Plasmonic Modulator Optimized by Patterning of Active Layer and Tuning Permittivity

    CERN Document Server

    Babicheva, Viktoriia E

    2012-01-01

    We study a metal-insulator-metal waveguide as a surface plasmon polariton modulator. A multilayered core consists of a silicon nitride layer and an ultrathin active layer sandwiched between two silver plates that serve as electrodes. A transparent conducting oxide, indium tin oxide (ITO), as an ultrathin active layer with the varied carrier density is utilized. Under various anneal conditions different permittivity of ITO can be achieved, and we analyse it influence on the modulator efficiency. To advance the modulator design, namely to increase transmittance and enhance modulation depth, we propose to substitute the continuous active layer by a one-dimension periodic grating. The dependence on the pattern size and filling factor of the active material is analyzed for tuned permittivity of the ITO layer.

  1. Experimental measurements and numerical simulation of permittivity and permeability of Teflon in X band

    Directory of Open Access Journals (Sweden)

    Adriano Luiz de Paula

    2011-01-01

    Full Text Available Recognizing the importance of an adequate characterization of radar absorbing materials, and consequently their development, the present study aims to contribute for the establishment and validation of experimental determination and numerical simulation of electromagnetic materials complex permittivity and permeability, using a Teflon® sample. The present paper branches out into two related topics. The first one is concerned about the implementation of a computational modeling to predict the behavior of electromagnetic materials in confined environment by using electromagnetic three-dimensional simulation. The second topic re-examines the Nicolson-Ross-Weir mathematical model to retrieve the constitutive parameters (complex permittivity and permeability of a homogeneous sample (Teflon®, from scattering coefficient measurements. The experimental and simulated results show a good convergence that guarantees the application of the used methodologies for the characterization of different radar absorbing materials samples.

  2. Electron irradiation induced reduction of the permittivity in chalcogenide glass (As2S3) thin film

    KAUST Repository

    San-Román-Alerigi, Damián P.

    2013-01-01

    In this paper, we investigate the effect of electron beam irradiation on the dielectric properties of As 2 S 3 chalcogenide glass. By means of low-loss electron energy loss spectroscopy, we derive the permittivity function, its dispersive relation, and calculate the refractive index and absorption coefficients under the constant permeability approximation. The measured and calculated results show a heretofore unseen phenomenon: a reduction in the permittivity of ? 40 %. Consequently a reduction of the refractive index of 20%, hence, suggests a conspicuous change in the optical properties of the material under irradiation with a 300 keV electron beam. The plausible physical phenomena leading to these observations are discussed in terms of the homopolar and heteropolar bond dynamics under high energy absorption. The reported phenomena, exhibited by As 2 S 3-thin film, can be crucial for the development of photonics integrated circuits using electron beam irradiation method. © 2013 American Institute of Physics.

  3. In vivo and in situ measurement and modelling of intra-body effective complex permittivity

    DEFF Research Database (Denmark)

    Nadimi, Esmaeil S; Blanes-Vidal, Victoria; Harslund, Jakob L F

    2015-01-01

    Radio frequency tracking of medical micro-robots in minimally invasive medicine is usually investigated upon the assumption that the human body is a homogeneous propagation medium. In this Letter, the authors conducted various trial programs to measure and model the effective complex permittivity ε...... contractions and simulated peristaltic movements of the GI tract organs inside the abdominal cavity and in the presence of the abdominal wall on the measurements and variations of ε' and ε''. They advanced the previous models of effective complex permittivity of a multilayer inhomogeneous medium, by estimating...... an analytical model that accounts for reflections between the layers and calculates the attenuation that the wave encounters as it traverses the GI tract and the abdominal wall. They observed that deviation from the specified nominal layer thicknesses due to non-geometric boundaries of GI tract morphometric...

  4. Permittivity and permeability of pentagon configuration molecules with different symmetry breaking and their applications

    Science.gov (United States)

    Shen, Yao; Chen, YuZhu

    2017-07-01

    In nature, some molecules have broken conjugate symmetry configurations, which might result in a special optical phenomenon called negative refraction. Under such circumstances, both permittivity and permeability are negative simultaneously. When light at certain frequency is transmitted through a transparent medium (e.g., slide glass) in which a psychoactive drug with negative indexes has been deposited, the refracted light is detected at different locations in the transparent medium. This is because the refracted light travels in a direction opposite to the expected path when it passes through material with a negative index. Using this method, it is possible to distinguish synthetic cannabinoids from other abusive psychoactive drugs in the UV-vis region. In this study, we use a tight-binding model to calculate the permittivity and permeability of pentagonal configurations with different broken symmetries. Furthermore, a qualitative analysis of the negative refraction with respect to heptagonal models is discussed.

  5. Meta-lens design with low permittivity dielectric materials through smart transformation optics

    Science.gov (United States)

    Kim, Junhyun; Shin, Dongheok; Choi, Seungjae; Yoo, Do-Sik; Seo, Ilsung; Kim, Kyoungsik

    2015-09-01

    We report here a design method based on smart transformation optics (STO) to control the range of the permittivity values of the materials required to manufacture transformation optics devices. In particular, we show that it is possible to reduce the maximum electric permittivity value required to realize a STO device with certain functionality by means of a simple conceptual elastic stretching process. We illustrate the design procedure with two types of collimator meta-lens designs, which we call warping space collimator meta-lens and half fisheye collimator meta-lens, respectively. We provide design examples of these two types of lenses with the help of COMSOL Multiphysics software. These two design examples are fabricated with commonly available dielectric materials by means of 3D printing technology. For the functional verification of these two collimator lenses, we provide measurement results obtained with transverse electric waves of frequency range 7-13GHz.

  6. Permittivity and Electromagnetic Interference Shielding Investigations of Activated Charcoal Loaded Acrylic Coating Compositions

    Directory of Open Access Journals (Sweden)

    Sharief ud Din Khan

    2014-01-01

    Full Text Available Acrylic resin (AR based electromagnetic interference (EMI shielding composites have been prepared by incorporation of up to 30 wt% activated charcoal (AC in AR matrix. These composites have been characterized by XRD, Raman spectroscopy, scanning electron microscopy, dielectric, and EMI shielding measurement techniques. XRD patterns and Raman studies confirm the incorporation of AC particles inside AR matrix and suggest possible interactions between phases. The SEM images show that incorporation of AC particles leads to systematic change in the morphology of composites especially the formation of porous structure. The dielectric measurements show that 30 wt% AC loading composite display higher relative permittivity value (~79 compared to pristine AR (~5. Further, the porous structure, electrical conductivity, and permittivity value contribute towards EMI shielding effectiveness value of −36 dB (attenuation of >99.9% of incident radiation for these composites, thereby demonstrating their suitability for making efficient EMI shielding coatings.

  7. Relative Permittivity of Carbon Dioxide + Ethanol Mixtures prediction by means of Artificial Neural Networks

    Directory of Open Access Journals (Sweden)

    Gonzalo Astray

    2014-07-01

    Full Text Available CO2 + ethanol mixtures have a huge scientific interest and enormous relevance for many industrial processes. Obtaining of their chemical and physical properties is a fundamental task. Relative permittivity (r of these mixtures is a key property because allows a better knowledge of the structure and the interactions in other media. In this work predictive values of relative permittivity (r of carbon dioxide + ethanol mixtures were obtained implementing artificial neural networks (ANNs. They are used successfully in very different fields; therefore it is a very useful tool. In this case the obtained results enhance the ones from the usual multiple linear regression analysis. In both cases mass fraction, pressure and temperature experimental data from a direct capacitance method were used.

  8. Nanoscale Electric Permittivity of Single Bacterial Cells at Gigahertz Frequencies by Scanning Microwave Microscopy.

    Science.gov (United States)

    Biagi, Maria Chiara; Fabregas, Rene; Gramse, Georg; Van Der Hofstadt, Marc; Juárez, Antonio; Kienberger, Ferry; Fumagalli, Laura; Gomila, Gabriel

    2016-01-26

    We quantified the electric permittivity of single bacterial cells at microwave frequencies and nanoscale spatial resolution by means of near-field scanning microwave microscopy. To this end, calibrated complex admittance images have been obtained at ∼19 GHz and analyzed with a methodology that removes the nonlocal topographic cross-talk contributions and thus provides quantifiable intrinsic dielectric images of the bacterial cells. Results for single Escherichia coli cells provide a relative electric permittivity of ∼4 in dry conditions and ∼20 in humid conditions, with no significant loss contributions. Present findings, together with the ability of microwaves to penetrate the cell membrane, open an important avenue in the microwave label-free imaging of single cells with nanoscale spatial resolution.

  9. Analytical calculation of permittivity tensors for invisibility devices using general relativity

    CERN Document Server

    Ahn, Doyeol

    2010-01-01

    Analytical expressions for the permittivity tensors of invisibility devices for the cases of elliptic cylinder, prolate spheroid, and the confocal paraboloid are obtained using general relativistic relations between the electromagnetic tensor and its dual tensor and their application to the transformation between the electromagnetic spacetime and the physical spacetime. This approach has a merit of being intuitive. In the case of elliptic cylinder, we found that the point of infinite light speed in the electromagnetic space becomes two points in the physical space for the zz component of the permittivity tensor. This result is different from the case of perfect cylinder in which there is a line of cloak at which the speed of light becomes infinite. In the cases of prolate spheroid and confocal paraboloid, the point of infinite light speed in the electromagnetic space becomes line in the physical space in all tensor components.

  10. Dielectric elastomers, with very high dielectric permittivity, based on silicone and ionic interpenetrating networks

    DEFF Research Database (Denmark)

    Yu, Liyun; Madsen, Frederikke Bahrt; Hvilsted, Søren;

    2015-01-01

    Dielectric elastomers (DEs), which represent an emerging actuator and generator technology, admittedly have many favourable properties, but their high driving voltages are one of the main obstacles to commercialisation. One way to reduce driving voltage is by increasing the ratio between dielectr...... as well as relatively high breakdown strength. All IPNs have higher dielectric losses than pure silicone elastomers, but when accounting for this factor, IPNs still exhibit satisfactory performance improvements....... is demonstrated herein, and a number of many and important parameters, such as dielectric permittivity/loss, viscoelastic properties and dielectric breakdown strength, are investigated. Ionic and silicone elastomer IPNs are promising prospects for dielectric elastomer actuators, since very high permittivities......Dielectric elastomers (DEs), which represent an emerging actuator and generator technology, admittedly have many favourable properties, but their high driving voltages are one of the main obstacles to commercialisation. One way to reduce driving voltage is by increasing the ratio between dielectric...

  11. Majority-Minority Influence: Identifying Argumentative Patterns and Predicting Argument-Outcome Links.

    Science.gov (United States)

    Meyers, Renee A.; Brashers, Dale E.; Hanner, Jennifer

    2000-01-01

    Identifies patterns of argument that characterize majority and minority communication in 34 discussions among small groups of students in decision-making situations. Finds that winning and losing subgroups argue differently (as do minority and majority subgroups overall) and that consistency in argument is a strong predictor of subgroup success.…

  12. Epistemic levels in argument: An analysis of university oceanography students' use of evidence in writing

    Science.gov (United States)

    Kelly, Gregory J.; Takao, Allison

    2002-05-01

    The purpose of this paper is to examine university oceanography students' use of evidence in writing. Drawing from rhetorical studies of science writing and studies of argumentation in science education, a model for assessing students' arguments is proposed that considers the relative epistemic status of propositions comprising students' written texts. The study was conducted in an introductory university oceanography course in a large public university that utilized an interactive CD-ROM that provided geological data sets for student exploration of scientific questions. Student arguments were analyzed through a process of sorting propositions by epistemic level and identifying the explicit links within and across levels. These epistemic levels were defined by discipline-specific geological constructs from descriptions of data, to identification of features, to relational aspects of features, to theoretically formulated assertions. This form of argumentation analysis allowed for assessment of each student's writing on normative grounds and for comparisons across students' papers. Results show promise for the argumentation model as a methodological tool. The examination of epistemic status of knowledge claims provided ways of distinguishing the extent to which students adhered to the genre conventions specified by the task, i.e., providing evidentiary support for their argument concerning the theory of plate tectonics with real earth data. We draw on the findings to discuss ways argumentation theory can contribute to reform in science education.

  13. Silicon electro-optic modulator with high-permittivity gate dielectric layer

    Institute of Scientific and Technical Information of China (English)

    Mengxia Zhu; Zhiping Zhou; Dingshan Gao

    2009-01-01

    A high-permittivity (high-k) material is applied as the gate dielectric layer in a silicon metal-oxidesemiconductor (MOS) capacitor to form a special electro-optic (EO) modulator.Both induced charge density and modulation efficiency in the proposed modulator are improved due to the special structure design and the application of the high-k material.The device has an ultra-compact dimension of 691 μm in length.

  14. High dielectric permittivity elastomers from well-dispersed expanded graphite in low concentrations

    DEFF Research Database (Denmark)

    Daugaard, Anders Egede; Hassouneh, Suzan Sager; Kostrzewska, Malgorzata;

    2013-01-01

    The development of elastomer materials with a high dielectric permittivity has attracted increased interest over the last years due to their use in for example dielectric electroactive polymers. For this particular use, both the electrically insulating properties - as well as the mechanical...... by the addition of traditional fillers in the necessary amounts would either lose their stability or their softness. Furthermore the influence of several mixing procedures on the electrical and mechanical properties is investigated. © 2013 SPIE....

  15. Experimental Investigation of Electrical Conductivity and Permittivity of SC-TiO 2 -EG Nanofluids

    Science.gov (United States)

    Fal, Jacek; Barylyak, Adriana; Besaha, Khrystyna; Bobitski, Yaroslav V.; Cholewa, Marian; Zawlik, Izabela; Szmuc, Kamil; Cebulski, Józef; żyła, Gaweł

    2016-08-01

    The paper presents experimental studies of dielectric properties of nanofluids based on ethylene glycol and SC-TiO2 nanoparticles with average size of 15-40 nm with various mass concentrations. The dielectric permittivity both real part and imaginary part as a function of temperature and frequency were measured. Also, dependence ac conductivity on frequency, temperature, and mass concentration were investigated. Based on the curves of ac conductivity, dc conductivity was calculated, and 400 % enhancement in dc conductivity was exposed.

  16. The analysis of the electromagnetic characteristics of composite materials with negative effective permittivity

    Institute of Scientific and Technical Information of China (English)

    BAO Yongfang; LU Yinghua; HE Pengfei; HAN Chunyuan

    2007-01-01

    A new method based on the finite difference time domain(FDTD) method is presented to numerically analyze the transmission and reflection characteristic of composite materials with negative effective permittivity.The numerical results are compared with the results of the existing theoretical model and the experimental data.The feasibility of analyzing the composite materials using the FDTD method is validated.It is useful for the design and application of the composite materials.

  17. Experimental Investigation of Electrical Conductivity and Permittivity of SC-TiO 2 -EG Nanofluids.

    Science.gov (United States)

    Fal, Jacek; Barylyak, Adriana; Besaha, Khrystyna; Bobitski, Yaroslav V; Cholewa, Marian; Zawlik, Izabela; Szmuc, Kamil; Cebulski, Józef; Żyła, Gaweł

    2016-12-01

    The paper presents experimental studies of dielectric properties of nanofluids based on ethylene glycol and SC-TiO2 nanoparticles with average size of 15-40 nm with various mass concentrations. The dielectric permittivity both real part and imaginary part as a function of temperature and frequency were measured. Also, dependence ac conductivity on frequency, temperature, and mass concentration were investigated. Based on the curves of ac conductivity, dc conductivity was calculated, and 400 % enhancement in dc conductivity was exposed.

  18. Strategic Use of Multiple Texts for the Evaluation of Arguments

    Science.gov (United States)

    Kobayashi, Keiichi

    2010-01-01

    Two experiments were conducted to examine whether students use arguments with refutation in one text for evaluating the opposite arguments without refutation in another text. Undergraduate students read two conflicting texts in either of the two orders: pro arguments text first and con arguments text first. After reading each text, they evaluated…

  19. The Nature and Function of Argument in Organizational Bargaining Research.

    Science.gov (United States)

    Keough, Colleen M.

    1987-01-01

    Responds to calls for explication of the theoretical basis of argument in negotiation. Uses four current argumentative perspectives to examine the nature and function of argument in organizational bargaining research, and concludes that Toulmin's argument field perspective offers the most thorough analysis of labor-management negotiations. (SKC)

  20. Verbal ability, argument order, and attitude formation

    Directory of Open Access Journals (Sweden)

    Mindaugas Mozuraitis

    2016-09-01

    Full Text Available The current study explored the interaction of verbal ability and presentation order on readers’ attitude formation when presented with two-sided arguments. Participants read arguments for and against compulsory voting and genetic engineering, and attitudes were assessed before and after reading the passages. Participants’ verbal ability was measured combining vocabulary knowledge and reading comprehension skill. Results suggested that low verbal-ability participants were more persuaded by the most recent set of arguments whereas high verbal-ability participants formed attitudes independent of presentation order. Contrary to previous literature, individual differences in the personality trait, need for cognition, did not interact with presentation order. The results suggest that verbal ability is an important moderator of the effect of presentation order when formulating opinions from complex prose.

  1. PBR theorem and Einstein's quantum hole argument

    CERN Document Server

    Weinstein, Galina

    2013-01-01

    This note discusses the latest hot topic: Quantum states: ontic or epistemic? and the PBR theorem. Upon reading Einstein's views on quantum incompleteness in publications or in his correspondence after 1935 (the EPR paradox), one gets a very intense feeling of deja-vu. Einstein presents a quantum hole argument, which somewhat reminds of the hole argument in his 1914 "Entwurf" general theory of relativity. In their paper, PBR write the following: "an important step towards the derivation of our result is the idea that the quantum state is physical if distinct quantum states correspond to non-overlapping distributions for [the set of possible physical states that a system can be in]", and they then refer to Einstein's argument and views.

  2. The origin dependence of the material constants: the permittivity and the inverse permeability

    Science.gov (United States)

    Anelli, Marco; Jonsson, Dan; Fliegl, Heike; Ruud, Kenneth

    2015-07-01

    New derivations of origin-independent expressions for the electric permittivity are presented, starting either from the response function of the current density that defines the absorption coefficient, or from the off-resonance single-photon scattering amplitude that leads to the Kramers-Heisenberg dispersion formula. The resulting expression for the permittivity is compared with earlier work on the origin dependence of the material constants. Different origin-independent expressions for the permittivity, the inverse permeability and the magnetisability are calculated and discussed. By considering electromagnetic plane waves in the absence of external sources, the macroscopic Maxwell equations are used to describe the response of matter to external fields. In combination with the constitutive relations, a wave equation expressed in terms of the material constants is derived. It is shown that the different definitions of the material constants lead to the same wave equation. The non-uniqueness of the definitions of the material constants is discussed in this context. Finally, based on the discussions, we propose a possible unique, origin-independent definition of the material constants.

  3. Negative static permittivity and violation of Kramers-Kronig relations in quasi-two-dimensional crystals

    Science.gov (United States)

    Nazarov, V. U.

    2015-10-01

    We investigate the wave vector and frequency-dependent screening of the electric field in atomically thin (quasi-two-dimensional) crystals. For graphene and hexagonal boron nitride we find that, above a critical wave vector qc, the static permittivity ɛ (q >qc,ω =0 ) becomes negative and the Kramers-Kronig relations do not hold for ɛ (q >qc,ω ) . Thus, in quasi-two-dimensional crystals, we reveal the physical confirmation of a proposition put forward decades ago [D. A. Kirzhnits, Sov. Phys. Usp. 19, 530 (1976), 10.1070/PU1976v019n06ABEH005268], allowing for the breakdown of Kramers-Kronig relations and for negative static permittivity. In the vicinity of the critical wave vector, we find a giant growth of the permittivity. Our results, obtained in the ab initio calculations using both the random-phase approximation and the adiabatic time-dependent local-density approximation, and further confirmed with a simple slab model, allow us to argue that the above properties, being exceptional in the three-dimensional case, are common to quasi-two-dimensional systems.

  4. A variational formulation of electrostatics in a medium with spatially varying dielectric permittivity.

    Science.gov (United States)

    Jadhao, Vikram; Solis, Francisco J; Olvera de la Cruz, Monica

    2013-02-07

    In biological and synthetic materials, many important processes involve charges that are present in a medium with spatially varying dielectric permittivity. To accurately understand the role of electrostatic interactions in such systems, it is important to take into account the spatial dependence of the permittivity of the medium. However, due to the ensuing theoretical and computational challenges, this inhomogeneous dielectric response of the medium is often ignored or excessively simplified. We develop a variational formulation of electrostatics to accurately investigate systems that exhibit this inhomogeneous dielectric response. Our formulation is based on a true energy functional of the polarization charge density. The defining characteristic of a true energy functional is that at its minimum it evaluates to the actual value of the energy; this is a feature not found in many commonly used electrostatic functionals. We explore in detail the charged systems that exhibit sharp discontinuous change in dielectric permittivity, and we show that for this case our functional reduces to a functional of only the surface polarization charge density. We apply this reduced functional to study model problems for which analytical solutions are well known. We demonstrate, in addition, that the functional has many properties that make it ideal for use in molecular dynamics simulations.

  5. A generalization of Dung's Abstract Framework for Argumentation

    DEFF Research Database (Denmark)

    Nielsen, Søren Holbech; Parsons, Simon

    2006-01-01

    One of the most widely studied systems of argumentation is the one described by Dung in a paper from 1995. Unfortunately, this framework does not allow for joint attacks on arguments, which we argue must be required of any truly abstract argumentation framework. A few frameworks can be said...... to allow for such interactions among arguments, but for various reasons we believe that these are inadequate for modelling argumentation systems with joint attacks. In this paper we propose a generalization of the framework of Dung, which allows for sets of arguments to attack other arguments. We extend...

  6. Modelling Scientific Argumentation in the Classroom : Teachers perception and practice

    Science.gov (United States)

    Probosari, R. M.; Sajidan; Suranto; Prayitno, B. A.; Widyastuti, F.

    2017-02-01

    The purposes of this study were to investigate teacher’s perception about scientific argumentation and how they practice it in their classroom. Thirty biology teachers in high school participated in this study and illustrated their perception of scientific argumentation through a questionnaire. This survey research was developed to measure teachers’ understanding of scientific argumentation, what they know about scientific argumentation, the differentiation between argument and reasoning, how they plan teaching strategies in order to make students’ scientific argumentation better and the obstacles in teaching scientific argumentation. The result conclude that generally, teachers modified various representation to accommodate student’s active participation, but most of them assume that argument and reasoning are similar. Less motivation, tools and limited science’s knowledge were considered as obstacles in teaching argumentation. The findings can be helpful to improving students’ abilities of doing scientific argumentation as a part of inquiry.

  7. Argumentative Polylogues: Beyond Dialectical Understanding of Fallacies

    Directory of Open Access Journals (Sweden)

    Lewiński Marcin

    2014-03-01

    Full Text Available Dialectical fallacies are typically defined as breaches of the rules of a regulated discussion between two participants (di-logue. What if discussions become more complex and involve multiple parties with distinct positions to argue for (poly-logues? Are there distinct argumentation norms of polylogues? If so, can their violations be conceptualized as polylogical fallacies? I will argue for such an approach and analyze two candidates for argumentative breaches of multi-party rationality: false dilemma and collateral straw man.

  8. Study of the low-frequency dispersion of permittivity and resistivity in tight rocks

    Science.gov (United States)

    Liu, Hongqi; Jie, Tian; Li, Bo; Youming, Deng; Chunning, Qiu

    2017-08-01

    The road to understanding the frequency dispersion (relaxation) of permittivity and resistivity in tight rocks remains relatively uncharted. Our team from Da'anzhai Group, Jurassic formation, Sichuan Basin carried out practical research to explore this phenomenon. The research was conducted under laboratory conditions for a selection of low frequencies, with ranges between 0.1 Hz to 1 kHz. Our research has shown that, although both the permittivity and resistivity decrease as the frequency increases, the two individual metrics display different behaviours when compared with each other. While the degree of resistivity variation is minimal, to the point that it is redundant, the permittivity, on the other hand, demonstrates something that is scientifically noteworthy. Permittivity has a distinctive dispersion degree across the entire sample of frequencies and the difference between the minimum and maximum frequencies is several orders of magnitude. An additional, and unexpected, learning from our research is that the level of frequency dispersion increases as the water saturation and concentration increases. In this paper, a collection of equations has been formulated to describe this relationship. These equations particularly shed light on the areas of rock porosity and saturation. They also show that the degree of frequency dispersion of permittivity or resistivity can be used as a function of water saturation and concentration. Two new variables are introduced here, DR and DC, to demonstrate the relaxation law quantitatively. In our practical research, we have characterised the relationship between the saturation and concentration with dielectric relaxation, using three different concentrations of DR and DC and five different saturations of NaCl solution. In difference to conventional Archie's multiple experimental parameters, we have established a new formula to derive the saturation from Rp and Cp, or from DR and DC directly. Two important frequencies were also

  9. Evidence of dual channel electron transfer induced negative magnetic field effect on exciplex emission at very high permittivity of medium

    Science.gov (United States)

    Jana, Amit Kumar; Roy, Partha; Nath, Deb Narayan

    2012-05-01

    Magnetic field induced change in the pyrene-N,N-dimethylaniline exciplex fluorescence has been studied in condensed phase with very high permittivity. In contrast to the commonly observed enhancement of exciplex fluorescence in presence of magnetic field (for 7 MFE at blue end slowly reverts back to the normal. At the red end of the emission the MFE retains its normal character for all donor concentrations even at very high permittivity.

  10. The Anthropic Argument against Infinite Past and the Eddington-Lemaitre Universe

    CERN Document Server

    Cirkovic, M M

    2000-01-01

    This study in the philosophy of cosmology is a part of an ongoing effort to investigate and reassess the importance of the anthropic (Davies-Tipler) argument against cosmologies containing the past temporal infinity. Obviously, the prime targets of this argument are cosmological models stationary on sufficiently large scale, the classical steady state model of Bondi, Gold and Hoyle being the best example. Here we investigate the extension of application of this argument to infinitely old non-stationary models and discuss additional constraints necessary to be imposed on such models for the edge of the anthropic argument to be preserved. An illustrative counterexample is the classical Eddington-Lemaitre model, in the analysis of which major such constraints are presented. Consequences of such an approach for our understanding of the nature of time are briefly discussed.

  11. The anthropic argument against infinite past and the Eddington-Lemaitre universe

    Directory of Open Access Journals (Sweden)

    Ćirković M.M.

    2000-01-01

    Full Text Available This study in the philosophy of cosmology is a part of an ongoing effort to investigate and reassess the importance of the anthropic (Davies-Tipler argument against cosmologies containing the past temporal infinity. Obviously the prime targets of this argument are cosmological models stationary on sufficiently large scale, the classical steady state model of Bondi, Gold and Hoyle being the best example. Here we investigate the extension of application of this argument to infinitely old non-stationary models and discuss additional constraints necessary to be imposed on such models for the edge of the anthropic argument to be preserved. An illustrative counterexample is the classical Eddington-Lemaitre model, in the analysis of which major such constraints are presented. Consequences of such an approach for our understanding of the nature of time are briefly discussed.

  12. Interface and permittivity simultaneous reconstruction in electrical capacitance tomography based on boundary and finite-elements coupling method.

    Science.gov (United States)

    Ren, Shangjie; Dong, Feng

    2016-06-28

    Electrical capacitance tomography (ECT) is a non-destructive detection technique for imaging the permittivity distributions inside an observed domain from the capacitances measurements on its boundary. Owing to its advantages of non-contact, non-radiation, high speed and low cost, ECT is promising in the measurements of many industrial or biological processes. However, in the practical industrial or biological systems, a deposit is normally seen in the inner wall of its pipe or vessel. As the actual region of interest (ROI) of ECT is surrounded by the deposit layer, the capacitance measurements become weakly sensitive to the permittivity perturbation occurring at the ROI. When there is a major permittivity difference between the deposit and the ROI, this kind of shielding effect is significant, and the permittivity reconstruction becomes challenging. To deal with the issue, an interface and permittivity simultaneous reconstruction approach is proposed. Both the permittivity at the ROI and the geometry of the deposit layer are recovered using the block coordinate descent method. The boundary and finite-elements coupling method is employed to improve the computational efficiency. The performance of the proposed method is evaluated with the simulation tests. This article is part of the themed issue 'Supersensing through industrial process tomography'.

  13. An Evaluation of the Permittivity of Two Different Rock Types Using Microwave Resonator and Waveguide Cutoff Principles

    Science.gov (United States)

    Olkkonen, Martta-Kaisa; Eskelinen, Pekka; Huuskonen-Snicker, Eeva; Pellinen, Terhi; Olmos Martinez, Pablo

    2015-01-01

    Methods of measuring the complex permittivity of different rock types are demonstrated in the frequency range from 6 GHz to 17 GHz. The used methods are based on the cylindrical resonator and waveguide cutoff frequency principles. This study is part of a larger research project that aims to characterize the electrical properties of asphalt for road surveying purposes. The studied rock types are metavolcanic rock with intermediate composition and pegmatite. The permittivity values gained with the resonator method are 6.2 for the metavolcanic rock and 4.5 for the pegmatite rock type, whereas the imaginary parts are 0.04 and 0.02. The permittivity values gained with the cutoff frequency method are 6.17 and 4.76 respectively. A reference measurement was made only for the metavolcanic rock in a transmission configuration with two antennas and the permittivity result was 6.21. The three different methods provide consistent permittivity values and are suitable for reliable permittivity evaluation.

  14. Risk assessment as an argumentation game

    NARCIS (Netherlands)

    Prakken, Henry; Ionita, Dan; Wieringa, Roel; Leite, J.; Son, T.C.; Torrini, P.; Van Der Torre, L.; Woltran, S.

    2013-01-01

    This paper explores the idea that IT security risk assessment can be formalized as an argumentation game in which assessors argue about how the system can be attacked by a threat agent and defended by the assessors. A system architecture plus assumptions about the environment is specified as an ASPI

  15. Beskrivelse, redegørelse, argumentation

    DEFF Research Database (Denmark)

    Ulbæk, Ib

    2017-01-01

    Foredraget vil redegøre for en eksperimentel undersøgelse af, hvorvidt fremstillingsformer er noget, som læsere af tekster, kan identificere. Der er valgt tekster af typerne beskrivelse, redegørelse og argumentation. Forsøgsdeltagerne bliver bedt om, at kategorisere teksterne ved at benytte de tr...

  16. Social values as arguments : similar is convincing

    NARCIS (Netherlands)

    Maio, Gregory R; Hahn, Ulrike; Frost, John-Mark; Kuppens, Toon; Rehman, Nadia; Kamble, Shanmukh

    2014-01-01

    Politicians, philosophers, and rhetors engage in co-value argumentation: appealing to one value in order to support another value (e.g., "equality leads to freedom"). Across four experiments in the United Kingdom and India, we found that the psychological relatedness of values affects the persuasive

  17. Test Fairness and Toulmin's Argument Structure

    Science.gov (United States)

    Kunnan, Antony John

    2010-01-01

    This paper presents the author's response to Xiaoming Xi's article titled "How do we go about investigating test fairness?" In this response, the author focuses on test fairness and Toulmin's model of argument structure, Xi's proposal, and the challenges the proposal brings. Xi proposes an approach to investigating test fairness to guide…

  18. Constructing Arguments with 3-D Printed Models

    Science.gov (United States)

    McConnell, William; Dickerson, Daniel

    2017-01-01

    In this article, the authors describe a fourth-grade lesson where 3-D printing technologies were not only a stimulus for engagement but also served as a modeling tool providing meaningful learning opportunities. Specifically, fourth-grade students construct an argument that animals' external structures function to support survival in a particular…

  19. The COUNSELOR Project: Understanding Legal Argument.

    Science.gov (United States)

    1986-01-01

    cannot reasonably expect the judge to maintain a " tabula rasa " mentality, where his y decision is presumably based only on the propositions presented...this is the case, then the role of the audience becomes crucial. Since the audience in legal argumentation is a very specialized group, it is

  20. Architecture-based regulatory compliance argumentation

    DEFF Research Database (Denmark)

    Mihaylov, Boyan; Onea, Lucian; Hansen, Klaus Marius

    2016-01-01

    the approach on the migration of the telemedicine platform Net4Care to the cloud, where certain regulations (for example privacy) should be concerned. The approach has the potential to support simpler compliance argumentation with the eventual promise of safer and more secure applications....

  1. Det demokratiske argument for absolut ytringsfrihed

    DEFF Research Database (Denmark)

    Lægaard, Sune

    2014-01-01

    Artiklen diskuterer den påstand, at absolut ytringsfrihed er en nødvendig forudsætning for demokratisk legitimitet med udgangspunkt i en rekonstruktion af et argument fremsat af Ronald Dworkin. Spørgsmålet er, hvorfor ytringsfrihed skulle være en forudsætning for demokratisk legitimitet, og hvorf...

  2. Argumentative Strategies in American and Japanese English.

    Science.gov (United States)

    Kamimura, Taeko; Oi, Kyoko

    1998-01-01

    A study examined differences in argumentative strategies in Japanese and American English by analyzing English essays on capital punishment written by 22 American high school seniors and 30 Japanese college sophomores. Differences were found in the organizational patterns, content and use of rational appeals, preference for type of diction, and…

  3. Det demokratiske argument for absolut ytringsfrihed

    DEFF Research Database (Denmark)

    Lægaard, Sune

    2014-01-01

    Artiklen diskuterer den påstand, at absolut ytringsfrihed er en nødvendig forudsætning for demokratisk legitimitet med udgangspunkt i en rekonstruktion af et argument fremsat af Ronald Dworkin. Spørgsmålet er, hvorfor ytringsfrihed skulle være en forudsætning for demokratisk legitimitet, og hvorfor...

  4. Contesting Pornography: Terministic Catharsis and Definitional Argument.

    Science.gov (United States)

    Palczewski, Catherine Helen

    2001-01-01

    Focuses on the debates over the MacKinnon-Dworkin Anti-Pornography Ordinance to explore one instance of definitional argument: the attempt to effect a redefinition. Argues that advocates for a definitional shift created the possibility for a "terministic catharsis" by simultaneously locating pornography in multiple locations on the pentad,…

  5. Verbal directionality and argument alternation in Dinka

    DEFF Research Database (Denmark)

    Andersen, Torben

    2012-01-01

    (wards) an explicit or implicit goal. The object of a directional verb may play another role in the event described by the sentence than the object of the corresponding simple (and non-directional) verb. This gives rise to so-called argument alternation, in that, for instance, an object and an instrumental adverbial...

  6. Brainstorming Versus Arguments Structuring in Online Forums

    Directory of Open Access Journals (Sweden)

    Abdulrahman Alqahtani

    2016-10-01

    Full Text Available We characterize electronic discussion forums as being of one of the following two types: Brainstorming Forums and Arguments Structuring Forums. In this work we analyze and classify the types of threading models occurring as a function of the type of forum. For our analysis we study forums attached to the 25 news sources most used by the aggregator Google News, as detected by a 2007 study. Most discussion forums associated with articles on these news sources seem to be designed not with the purpose of structuring arguments but mainly with the purpose of helping readers brainstorm easily their reactions to the corresponding news item. The forums were classified as to what user-supported metadata they gather and use in comment presentation. We compare the features observed for brainstorming forums, as learned via the aforementioned procedure, with the fea-tures of dedicated argument structuring forums. The argument structuring forums that were used as basis of the comparison are: YourView, DebateDecide, and Opinion Space. We notice significant differences in the obtained models for the two types of forums, as well as significant differences with respect to the the structuring of user submitted data in polls associated with major news channels. We believe that this is the first kind of work that deals with the issue above.

  7. Teachers' Pedagogical Design Capacity for Scientific Argumentation

    Science.gov (United States)

    Knigh-Bardsley Amanda; McNeill, Katherine L.

    2016-01-01

    Despite being identified as an essential scientific practice, argumentation is rarely integrated into instruction. This could be influenced by teachers' pedagogical design capacity (PDC), which considers teaching as a design activity influenced by both instructional resources (such as tools and professional development (PD)) and teacher resources…

  8. Evaluating arguments during instigations of defence motivation and accuracy motivation.

    Science.gov (United States)

    Liu, Cheng-Hong

    2017-05-01

    When people evaluate the strength of an argument, their motivations are likely to influence the evaluation. However, few studies have specifically investigated the influences of motivational factors on argument evaluation. This study examined the effects of defence and accuracy motivations on argument evaluation. According to the compatibility between the advocated positions of arguments and participants' prior beliefs and the objective strength of arguments, participants evaluated four types of arguments: compatible-strong, compatible-weak, incompatible-strong, and incompatible-weak arguments. Experiment 1 revealed that participants possessing a high defence motivation rated compatible-weak arguments as stronger and incompatible-strong ones as weaker than participants possessing a low defence motivation. However, the strength ratings between the high and low defence groups regarding both compatible-strong and incompatible-weak arguments were similar. Experiment 2 revealed that when participants possessed a high accuracy motivation, they rated compatible-weak arguments as weaker and incompatible-strong ones as stronger than when they possessed a low accuracy motivation. However, participants' ratings on both compatible-strong and incompatible-weak arguments were similar when comparing high and low accuracy conditions. The results suggest that defence and accuracy motivations are two major motives influencing argument evaluation. However, they primarily influence the evaluation results for compatible-weak and incompatible-strong arguments, but not for compatible-strong and incompatible-weak arguments. © 2016 The British Psychological Society.

  9. Reliably measuring the condition of mineral-based transfer fluids using a permittivity sensor – practical application to thermal fluid heat transfer

    Directory of Open Access Journals (Sweden)

    Christopher Ian Wright

    2015-09-01

    Full Text Available This article describes a series of experiments to assess the performance and suitability of a permittivity sensor in the area of heat transfer. The permittivity sensor measures condition index and temperature of a fluid. A series of 5 experiments was conducted. They assessed the reproducibility of the sensor using both clean and dirty fluid samples, and showed the sensor had good reproducibility based on calculations of coefficients of variation. The sensor also detected water contamination, assessed from construction of a stimulus-response curve to step-wise increases in water and from real-life samples where water content was reported to be out of specification. Further experiments tested the association between condition index and both water content and fluid cleanliness in a real-life setting. Results demonstrated the sensor that condition index reflected changes in fluid water and cleanliness and was therefore a measure of fluid condition. The implication of these findings is that the sensor can be used to make rapid and reliable assessments of fluid condition using only small samples (i.e., <50 ml. The sensor may be of benefit to customers that need to make a lot of regular samples over a large processing site, such as concentrated solar power plants.

  10. 1D/2D Carbon Nanomaterial-Polymer Dielectric Composites with High Permittivity for Power Energy Storage Applications.

    Science.gov (United States)

    Dang, Zhi-Min; Zheng, Ming-Sheng; Zha, Jun-Wei

    2016-04-06

    With the development of flexible electronic devices and large-scale energy storage technologies, functional polymer-matrix nanocomposites with high permittivity (high-k) are attracting more attention due to their ease of processing, flexibility, and low cost. The percolation effect is often used to explain the high-k characteristic of polymer composites when the conducting functional fillers are dispersed into polymers, which gives the polymer composite excellent flexibility due to the very low loading of fillers. Carbon nanotubes (CNTs) and graphene nanosheets (GNs), as one-dimensional (1D) and two-dimensional (2D) carbon nanomaterials respectively, have great potential for realizing flexible high-k dielectric nanocomposites. They are becoming more attractive for many fields, owing to their unique and excellent advantages. The progress in dielectric fields by using 1D/2D carbon nanomaterials as functional fillers in polymer composites is introduced, and the methods and mechanisms for improving dielectric properties, breakdown strength and energy storage density of their dielectric nanocomposites are examined. Achieving a uniform dispersion state of carbon nanomaterials and preventing the development of conductive networks in their polymer composites are the two main issues that still need to be solved in dielectric fields for power energy storage. Recent findings, current problems, and future perspectives are summarized.

  11. Argumentation research and its implications in science preservice teachers’ training

    Directory of Open Access Journals (Sweden)

    Archila, Pablo Antonio

    2012-09-01

    Full Text Available This article presents a literature review of argumentation research in sciences, it is motivated by the idea that recent advances in argumentation studies indicate that the topic of argumentation should be included in the curriculum and in science teachers’ preservice training. Firstly, some theoretical and practical benefits and developments of argumentation in sciences are exposed, localizing the field with Didactic of Science. Secondly, the intentions of researches which have explored ways for including argumentation in science preservice teachers training are described. Thirdly, the literature is analyzed in order to elucidate the implications of this localization. Finally, recommendations for the inclusion of argumentation in science preservice teachers’ training are proposed.

  12. Determining the relative impact of electrical conductivity and dielectric permittivity on the GPR early-time signal

    Science.gov (United States)

    Algeo, J.; Slater, L. D.; Binley, A. M.; Van Dam, R. L.; Watts, C. W.

    2016-12-01

    We employ early-time amplitude analysis, a recently developed ground-penetrating radar (GPR) methodology, in conjunction with electrical resistivity tomography (ERT) to determine the relative impact of dielectric permittivity and electrical conductivity on the GPR early-time signal (ETS). Early-time amplitude analysis uses changes in the amplitude of the overlapping GPR air- and ground-waves to resolve the electromagnetic properties of the subsurface. It has been employed to assess the water content of geologic materials at laboratory and field scales. As the amplitude of the ETS is dependent on both conductivity and permittivity, both of which can be affected by changes in soil water content, it is important to understand the relative magnitude of the impacts of these two parameters on GPR amplitude. Previous work in this field has related the early-time signal to conductivity and permittivity changes in a field setting, however these variations in electromagnetic properties were caused by changes in both lithology and water content. We carried out an irrigation experiment at the Butt Close and Honey Pot field sites in Woburn, Bedfordshire, UK, managed by Rothamstead Research, to explore how changes in conductivity and permittivity, caused by changes in water content, impact the ETS. Our GPR data provide early-time information and a measurement of permittivity from reflections off of a plow pan layer located at a constant depth in the subsurface. Data from the ERT survey provide a measurement of electrical conductivity. We modified the conductivity and permittivity of the subsurface by irrigating with groundwater. We carry out a multiple regression analysis to determine the relative impacts of changing conductivity and permittivity at the Butt Close and Honey Pot sites, and what effect these changes might have on estimates of soil water content. The results of our investigation help in the development of GPR ETS techniques for mapping and monitoring water content

  13. High electrical permittivity of ultrapure water at the water-platinum interface

    Science.gov (United States)

    Musumeci, Francesco; Pollack, Gerald H.

    2014-10-01

    The discharge of a platinum parallel-plate capacitor filled with ultrapure water has been measured. The observed discharge trend can be described by a Modified Poisson-Boltzmann Equation (MPB) only when the voltage is very low. Increasing the applied voltage creates an ‘exclusion zone' in which the MPB equation no longer fits, and the system capacitance shows a dependence on the spacing between the two platinum plates. The permittivity of water, calculated considering the system as a plane capacitor, appears to be very high. This implies that the exclusion zone could have extraordinary dielectric properties.

  14. Permittivity of dielectric composite materials comprising graphene nanoribbons. The effect of nanostructure.

    Science.gov (United States)

    Dimiev, Ayrat; Zakhidov, Dante; Genorio, Bostjan; Oladimeji, Korede; Crowgey, Benjamin; Kempel, Leo; Rothwell, Edward J; Tour, James M

    2013-08-14

    New lightweight, flexible dielectric composite materials were fabricated by the incorporation of several new carbon nanostructures into a dielectric host matrix. Both the permittivity and loss tangent values of the resulting composites were widely altered by varying the type and content of the conductive filler. The dielectric constant was tuned from moderate to very high values, while the corresponding loss tangent changed from ultralow to extremely high. The data exemplify that nanoscale changes in the structure of the conductive filler result in dramatic changes in the dielectric properties of composites. A microcapacitor model most explains the behavior of the dielectric composites.

  15. Silicone films with high stiffness and increasing permittivity through dipole-grafting

    Science.gov (United States)

    Bluemke, Martin; Wegener, Michael; Krueger, Hartmut

    2015-04-01

    Dielectric elastomer actuators (DEAs) are smart materials that can be optimized by modifying the dielectric or mechanical properties of the electroactive polymer. The incorporation of inorganic particles in silicone elastomers shows a permittivity enhancement and undesired stiffening. We present another concept to obtain comparable properties by dipole grafting. Therefore, the organic dipole N-ally-N-methyl-4-nitroaniline is grafted in competition with the vinyl terminated PDMS to a hydrosilane cross-linker forming the PDMS network. With this procedure PDMS films with up to 25 wt% of the dipole were solvent casted and the chemical, mechanical, electrical, plus electromechanical properties of these novel materials were investigated.

  16. Effective permittivity of single-walled carbon nanotube composites: Two-fluid model

    Energy Technology Data Exchange (ETDEWEB)

    Moradi, Afshin, E-mail: a.moradi@kut.ac.ir [Department of Engineering Physics, Kermanshah University of Technology, Kermanshah (Iran, Islamic Republic of); Department of Nano Sciences, Institute for Studies in Theoretical Physics and Mathematics (IPM), Tehran (Iran, Islamic Republic of); Zangeneh, Hamid Reza; Moghadam, Firoozeh Karimi [Department of Photonics, Faculty of Physics, University of Kashan, Kashan (Iran, Islamic Republic of)

    2015-12-15

    We develop an effective medium theory to obtain effective permittivity of a composite of two-dimensional (2D) aligned single-walled carbon nanotubes. Electronic excitations on each nanotube surface are modeled by an infinitesimally thin layer of a 2D electron gas represented by two interacting fluids, which takes into account different nature of the σ and π electrons. Calculations of both real and imaginary parts of the effective dielectric function of the system are presented, for different values of the filling factor and radius of carbon nanotubes.

  17. Effective permittivity of single-walled carbon nanotube composites: Two-fluid model

    Science.gov (United States)

    Moradi, Afshin; Zangeneh, Hamid Reza; Moghadam, Firoozeh Karimi

    2015-12-01

    We develop an effective medium theory to obtain effective permittivity of a composite of two-dimensional (2D) aligned single-walled carbon nanotubes. Electronic excitations on each nanotube surface are modeled by an infinitesimally thin layer of a 2D electron gas represented by two interacting fluids, which takes into account different nature of the σ and π electrons. Calculations of both real and imaginary parts of the effective dielectric function of the system are presented, for different values of the filling factor and radius of carbon nanotubes.

  18. Analysis of Dynamic Response of Permittivity in a Liquid Crystal Cell with Flow

    Science.gov (United States)

    Ozaki, R.; Matsuura, K.; Kadowaki, K.; Duong, T. Q.; Moritake, H.

    2016-04-01

    Microwave and millimeter-wave devices including a liquid crystal (LC) are increasingly attractive for the use in adaptive and controllable devices. Various types of microwave phase shifters having an LC transmission line have been studied (e.g. microstripline, coplanar waveguide, and rectangular waveguide). In conventional microwave devices, the response time after removal of voltage is slow because the LC layer in the devices is usually thick. In this study, the time response of the LC permittivity is studied experimentally and theoretically. Experimentally measured response curves having two time constants for decay are examined by using Frank’s continuum theory with and without the backflow effect.

  19. Complex permittivity, permeability and microwave absorbing properties of Co–Ti substituted strontium hexaferrite

    OpenAIRE

    Bindra Narang Sukhleen; Kaur Pawandeep; Bahel Shalini

    2016-01-01

    M-type strontium ferrite with compositions SrFe(12-2x)CoxTixO19 (x = 0.0, 0.3, 0.5, 0.7, 1.0), were prepared by two route ceramic method. The effects of Co–Ti substitution on their microstructure, electromagnetic properties, and microwave absorptive behavior were analyzed. The complex permittivity (∊′-j∊″) and complex permeability (μ′-jμ″) have been measured from 8.2 to 12.4 GHz using a network analyzer. Scanning electron microscope was used to analyze the grain size distribution and porosity...

  20. The Microscopic Origin of the Macroscopic Dielectric Permittivity of Crystals: A Mathematical Viewpoint

    CERN Document Server

    Cancès, Eric; Stoltz, Gabriel

    2010-01-01

    The purpose of this paper is to provide a mathematical analysis of the Adler-Wiser formula relating the macroscopic relative permittivity tensor to the microscopic structure of the crystal at the atomic level. The technical level of the presentation is kept at its minimum to emphasize the mathematical structure of the results. We also briefly review some models describing the electronic structure of finite systems, focusing on density operator based formulations, as well as the Hartree model for perfect crystals or crystals with a defect.

  1. Dipolar cross-linkers for PDMS networks with enhanced dielectric permittivity and low dielectric loss

    DEFF Research Database (Denmark)

    Bahrt, Frederikke; Daugaard, Anders Egede; Hvilsted, Søren

    2013-01-01

    Dipole grafted cross-linkers were utilized to prepare polydimethylsiloxane (PDMS) elastomers with various chain lengths and with various concentrations of functional cross-linker. The grafted cross-linkers were prepared by reaction of two alkyne-functional dipoles, 1-ethynyl-4-nitrobenzene and 3......-(4-((4-nitrophenyl)diazenyl)phenoxy)-prop-1-yn-1-ylium, with a synthesized silicone compatible azide-functional cross-linker by click chemistry. The thermal, mechanical and electromechanical properties were investigated for PDMS films with 0 to 3.6 wt% of dipole-cross-linker. The relative dielectric permittivity...

  2. Value-Based Argumentation for Justifying Compliance

    Science.gov (United States)

    Burgemeestre, Brigitte; Hulstijn, Joris; Tan, Yao-Hua

    Compliance is often achieved 'by design' through a coherent system of controls consisting of information systems and procedures . This system-based control requires a new approach to auditing in which companies must demonstrate to the regulator that they are 'in control'. They must determine the relevance of a regulation for their business, justify which set of control measures they have taken to comply with it, and demonstrate that the control measures are operationally effective. In this paper we show how value-based argumentation theory can be applied to the compliance domain. Corporate values motivate the selection of control measures (actions) which aim to fulfill control objectives, i.e. adopted norms (goals). In particular, we show how to formalize the dialogue in which companies justify their compliance decisions to regulators using value-based argumentation. The approach is illustrated by a case study of the safety and security measures adopted in the context of EU customs regulation.

  3. Design as Value Celebration: Rethinking Design Argumentation

    DEFF Research Database (Denmark)

    Halstrøm, Per Liljenberg

    2016-01-01

    This article introduces knowledge of the rhetorical genre of epideictic to design. The aim is to provide designers with concepts that stimulate their ability to deliberate about design choices and explore the arguments they may be making about the human-made world. The article begins...... with explorations of how to perceive the situations that designers may address; it then provides rhetorical perspectives that may be useful when creating design arguments; finally, examples of how to use these rhetorical perspectives in design are provided. Based on analyzed examples and theories on design problems......, situational perspectives, and rhetorical genres, the article concludes that designers can benefit from perceiving their design as value celebration rather than problem solving....

  4. Augmenting Tractable Fragments of Abstract Argumentation

    CERN Document Server

    Ordyniak, Sebastian

    2011-01-01

    We present a new and compelling approach to the efficient solution of important computational problems that arise in the context of abstract argumentation. Our approach makes known algorithms defined for restricted fragments generally applicable, at a computational cost that scales with the distance from the fragment. Thus, in a certain sense, we gradually augment tractable fragments. Surprisingly, it turns out that some tractable fragments admit such an augmentation and that others do not. More specifically, we show that the problems of credulous and skeptical acceptance are fixed-parameter tractable when parameterized by the distance from the fragment of acyclic argumentation frameworks. Other tractable fragments such as the fragments of symmetrical and bipartite frameworks seem to prohibit an augmentation: the acceptance problems are already intractable for frameworks at distance 1 from the fragments. For our study we use a broad setting and consider several different semantics. For the algorithmic results...

  5. Apocalypse Now? Reviving the Doomsday Argument

    CERN Document Server

    Simpson, Fergus

    2016-01-01

    Whether the fate of our species can be forecast from its past has been the topic of considerable controversy. One refutation of the so-called Doomsday Argument is based on the premise that we are more likely to exist in a universe containing a greater number of observers. Here we present a Bayesian reformulation of the Doomsday Argument which is immune to this effect. By marginalising over the spatial configuration of observers, we find that any preference for a larger total number of observers has no impact on the inferred local number. Our results remain unchanged when we adopt either the Self-Indexing Assumption (SIA) or the Self-Sampling Assumption (SSA). Furthermore the median value of our posterior distribution is found to be in agreement with the frequentist forecast. Humanity's prognosis for the coming century is well approximated by a global catastrophic risk of 0.2% per year.

  6. Which fine-tuning arguments are fine?

    CERN Document Server

    Grinbaum, Alexei

    2009-01-01

    The argument from naturalness is widely employed in contemporary quantum field theory. Essentially a formalized aesthetic criterion, it received a meaning in the debate on the Higgs mechanism, which goes beyond aesthetics. We follow the history of technical definitions of fine tuning at the scale of electroweak symmetry breaking. It is argued that they give rise to a special interpretation of probability, which we call Gedankenfrequency. By extension of its original meaning, the argument from naturalness is used to compare different models beyond the Standard Model. We show that in this case naturalness cannot be defined objectively. Rather, it functions as socio-historical heuristics in particle physics and it contributes to the advent of a probabilistic version of Popper's falsificationism.

  7. How to Write Argumentation in English Persuasively

    Institute of Scientific and Technical Information of China (English)

    苏祎甜

    2014-01-01

    <正>Some problems should be worked out first How to develop a good thesis statement?Thesis statement is the sentence that we look early in an essay for a one-or two-sentence condensation of the argument or analysis that is to follow.It offers a concise solution to the issue being addressed and a brief summary of all explained reasons in the paper.

  8. Construction of Argumentative Discourse in Foucaltian Perspective

    Directory of Open Access Journals (Sweden)

    Isabel Cristina Michelan de Azevedo

    2016-12-01

    Full Text Available This article draws upon the argumentative scheme described by New Rhetoric in order to discuss how the organization of reasonings by association and dissociation can be analyzed in Foucault’s studies (2008 [1969], 2004 [1971] on the constitution of discourse in society, aiming to promote a reflection about the possibilities of analysis of high school students productions and about the organization of argument teaching in basic education. Through an interpretative methodology (ERICKSON, 1986, we seek to understand the discursive movements gathered from productions made during the National Secondary Education Examination in 2004 and to indicate alternatives to develop pedagogical practices committed to the formation of a critical subject. Illustrative analyzes indicate that students prepare reflections authorized by certain discursive formation, task that requires the definition of an identity and the preparing of arguments aligned to the political choices discursively adopted. Thus, it becomes evident the need to diversify the teaching and learning processes when one want to expand the possibilities of the subject to take any stance relative to other positions.

  9. Argumentation and Inference: A Unified Approach

    Directory of Open Access Journals (Sweden)

    Christophe Fouqueré

    2013-12-01

    Full Text Available We propose in this paper to use Ludics as a unified framework for the analysis of dialogue and the reasoning system. Not only is Ludics a logical theory, but it may also be built by means of concepts of game theory. We first present the main concepts of Ludics. A design is an abstraction and a generalization of the concept of proof. Interaction between designs is equivalent to cut elimination or modus ponens in logical theories. It appears to be a natural means for representing dialogues and also for reasoning. A design is a set of sequences of alternate actions, similar to a move in game theory. We apply Ludics to argumentative dialogues. We discuss how to model the speech acts of argumentative dialogues in terms of dialogue acts. A dialogue act is given by a Ludics action together with the expression that reveals the action in a turn of speech. We show also how arguments may be stored in a commitment state used for reasoning. Finally we revisit an example of juridical dialogue that has been analyzed by Prakken in a different framework.

  10. "Evidence" Under a Magnifying Glass: Thoughts on Safety Argument Epistemology

    Science.gov (United States)

    Graydon, P. J.; Holloway, C. M.

    2015-01-01

    Common definitions of "safety case" emphasize that evidence is the basis of a safety argument, yet few widely referenced works explicitly define "evidence". Their examples suggest that similar things can be regarded as evidence. But the category evidence seems to contain (1) processes for finding things out, (2) information resulting from such processes, and (3) relevant documents. Moreover, any item of evidence could be replaced by further argument. Normative models of informal argumentation do not offer clear guidance on when a safety argument should cite evidence rather than appeal to a more detailed argument. Disciplines such as the law address the problem with a practical, domain-specific epistemology. In this paper, we explore these problems associated with evidence citations in safety arguments, identify goals for a theory of safety argument evidence and a practical safety argument epistemology, propose a model of safety evidence citation that advances the identified goals, and present a related extension to the Goal Structuring Notation (GSN).

  11. Common misrepresentation of the Einstein-Podolsky-Rosen argument

    CERN Document Server

    Hnizdo, V

    1998-01-01

    A frequently given version of the argument of Einstein, Podolsky and Rosen against the completeness of the quantum mechanical description is criticized as a misrepresentation that lacks the cogency of the original EPR argument.

  12. Measurements in Vacuum of the Effect of Ilmenite on the Complex Dielectric Permittivity of Planetary Regolith Analog Materials

    Science.gov (United States)

    Boivin, A.; Hickson, D.; Cunje, A.; Tsai, C. A.; Ghent, R. R.; Daly, M. G.

    2016-12-01

    When considering radar observations of airless bodies containing regolith, the radar backscattering coefficient is dependent on both the complex permittivity and the thickness of the regolith. The complex permittivity is typically normalized by the permittivity of free space (ɛ0) and reported as the relative permittivity (ɛr = ɛr' + iɛr'', where ɛr' is the dielectric constant and ɛr'' is the loss factor). Given the backscattering coefficient and the dielectric properties of the regolith, it should be possible to determine regolith thickness. This problem has long been considered for the Moon and many measurements of either real or complex permittivity have been made on both Apollo samples and regolith analogues. Measurements thus far have either only been done at a lower frequency range (baked at 250°C for 48hrs and are then placed in a vacuum chamber. Measurements are then made using a sweep of frequencies from 300 kHz to 8.5 GHz. Preliminary results show that ilmenite significantly influences signal attenuation, especially at high concentrations.

  13. Quantitatively analyzing dielectrical properties of resins and mapping permittivity variations in CFRP with high-frequency eddy current device technology

    Science.gov (United States)

    Gäbler, Simone; Heuer, Henning; Heinrich, Gert; Kupke, Richard

    2015-03-01

    Eddy current testing is well-established for non-destructive characterization of electrical conductive materials. The development of high-frequency eddy current technology (with frequency ranges up to 100 MHz) made it even possible to extend the classical fields of application towards less conductive materials like CFRP. Maxwell's equations and recent research show that the use of high-frequency eddy current technology is also suitable for non-conductive materials. In that case the change of complex impedance of the probing coil contains information on sample permittivity. This paper shows that even a quantitative measurement of complex permittivity with high-frequency eddy current device technology is possible using an appropriate calibration. Measurement accuracy is comparable to commercial capacitive dielectric analyzers. If the sample material is electrically conductive, both, permittivity and conductivity influence the complex impedance measured with high-frequency eddy current devices. Depending on the measurement setup and the sheet resistance of the sample a parallel characterization of both parameters is possible on isotropic multi-layer materials. On CFRP the permittivity measurement is much more complex due to the capacitive effects between the carbon rovings. However, first results show that at least the local permittivity variations (like those caused by thermal damages) are detectable.

  14. Pulsed picosecond and nanosecond discharge development in liquids with various dielectric permittivity constants

    Science.gov (United States)

    Starikovskiy, Andrey

    2016-09-01

    The dynamics of pulsed picosecond and nanosecond discharge development in liquid water, ethanol and hexane were investigated experimentally. It is shown that the dynamics of discharge formation fundamentally differ between liquids with low and high dielectric permittivity coefficients. The difference in the nanosecond discharge development in liquid dielectrics may be explained by the formation of micro-discontinuities in the media during the electrostriction compression/rarefaction stage in liquids with high dielectric permittivity. Three possible mechanisms for the propagation of discharge in liquids play a different role depending on the pulse duration. The first is the formation of low density channels in liquid. In the second case the electrostatic forces support the expansion of nanoscale voids behind the front of the ionization wave; in the wave front the extreme electric field provides a strong negative pressure in the dielectric fluid due to the presence of electrostriction forces, forming the initial micro-voids in the continuous medium. Finally, in the third case, when a picosecond electric pulse is utilized, the ionization in the liquid phase occurs as a result of direct electron impact without undergoing a phase transition.

  15. An automated phase correction algorithm for retrieving permittivity and permeability of electromagnetic metamaterials

    Directory of Open Access Journals (Sweden)

    Z. X. Cao

    2014-06-01

    Full Text Available To retrieve complex-valued effective permittivity and permeability of electromagnetic metamaterials (EMMs based on resonant effect from scattering parameters using a complex logarithmic function is not inevitable. When complex values are expressed in terms of magnitude and phase, an infinite number of permissible phase angles is permissible due to the multi-valued property of complex logarithmic functions. Special attention needs to be paid to ensure continuity of the effective permittivity and permeability of lossy metamaterials as frequency sweeps. In this paper, an automated phase correction (APC algorithm is proposed to properly trace and compensate phase angles of the complex logarithmic function which may experience abrupt phase jumps near the resonant frequency region of the concerned EMMs, and hence the continuity of the effective optical properties of lossy metamaterials is ensured. The algorithm is then verified to extract effective optical properties from the simulated scattering parameters of the four different types of metamaterial media: a cut-wire cell array, a split ring resonator (SRR cell array, an electric-LC (E-LC resonator cell array, and a combined SRR and wire cell array respectively. The results demonstrate that the proposed algorithm is highly accurate and effective.

  16. Electrodynamics of soft multilayered particles dispersions: dielectric permittivity and dynamic mobility.

    Science.gov (United States)

    Merlin, Jenny; Duval, Jérôme F L

    2014-08-01

    We report a theory for the evaluation of the electrodynamics of dispersions of spherical soft multilayered (bio)particles, with microorganisms and polyelectrolyte multilayers-coated particles as illustrative paradigms. These particles generally consist of a hard (ion- and water-impermeable) core component supporting a succession of step-function or diffuse-like concentric soft (permeable) polymeric layers defined by distinct electrostatic, hydrodynamic and structural properties. The formalism is based on a rigorous numerical resolution of the coupled Navier-Stokes-Brinkman equation, continuity equations for the flow and for the ionic species present in solution, and the non-linear Poisson equation corrected for the multilayered nature of the soft interphase. The frequency-dependent dynamic mobility and dielectric permittivity of such soft particles suspensions are discussed as a function of the key electrohydrodynamic features of the constituting particulate peripheral layers and solution salinity. It is shown that the frequency dependent permittivity is mostly affected by the total charge carried by the overall soft interphase. In contrast, the dynamic mobility is mainly determined by the charge and friction characteristics of the layers located within an electrokinetically-active outer particle region whose extension is defined by the electric double layer thickness and the Brinkman length. Results highlight that under particular electrolyte concentration and layer-to-layer thickness ratio conditions, the dynamic mobility may reflect the physico-chemical and structural properties of the only innermost layers of the soft particle coating.

  17. Argument-As-Procedure and "The Art of Controversy."

    Science.gov (United States)

    Hample, Dale; Dallinger, Judith M.

    Scholars have long been interested in the relation between rhetoric and dialectic. Recent theorists suggest that one way of viewing argument is through the perspective of argument-as-procedure, in which rules such as those attendant to the conduct of dialectic, debate, or discussion come under the purview of argumentation. This paper is a critical…

  18. Situating Standard Setting within Argument-Based Validity

    Science.gov (United States)

    Papageorgiou, Spiros; Tannenbaum, Richard J.

    2016-01-01

    Although there has been substantial work on argument-based approaches to validation as well as standard-setting methodologies, it might not always be clear how standard setting fits into argument-based validity. The purpose of this article is to address this lack in the literature, with a specific focus on topics related to argument-based…

  19. Factors impacting teachers' argumentation instruction in their science classrooms

    Science.gov (United States)

    McNeill, Katherine L.; Katsh-Singer, Rebecca; González-Howard, María; Loper, Suzanna

    2016-08-01

    Science education research, reform documents and standards include scientific argumentation as a key learning goal for students. The role of the teacher is essential for implementing argumentation in part because their beliefs about argumentation can impact whether and how this science practice is integrated into their classroom. In this study, we surveyed 42 middle school science teachers and conducted follow-up interviews with 25 to investigate the factors that teachers believe impact their argumentation instruction. Teachers responded that their own learning goals had the greatest impact on their argumentation instruction while influences related to context, policy and assessment had the least impact. The minor influence of policy and assessment was in part because teachers saw a lack of alignment between these areas and the goals of argumentation. In addition, although teachers indicated that argumentation was an important learning goal, regardless of students' backgrounds and abilities, the teachers discussed argumentation in different ways. Consequently, it may be more important to help teachers understand what counts as argumentation, rather than provide a rationale for including argumentation in instruction. Finally, the act of trying out argumentation in their own classrooms, supported through resources such as curriculum, can increase teachers' confidence in teaching argumentation.

  20. Impact of Model-Based Teaching on Argumentation Skills

    Science.gov (United States)

    Ogan-Bekiroglu, Feral; Belek, Deniz Eren

    2014-01-01

    The purpose of this study was to examine effects of model-based teaching on students' argumentation skills. Experimental design guided to the research. The participants of the study were pre-service physics teachers. The argumentative intervention lasted seven weeks. Data for this research were collected via video recordings and written arguments.…

  1. From Formalism to Inquiry: A Model of Argument in "Antigone."

    Science.gov (United States)

    Kastely, James L.

    1999-01-01

    Presents a definition for a formalist approach to teaching argument and discusses limitations and serious problems with this approach. Discusses "Antigone" as a representative text for teaching argument because it challenges the very possibility of argument. Proposes that literary texts such as "Antigone" be taught as…

  2. Scaffolding for Argumentation in Hypothetical and Theoretical Biology Concepts

    Science.gov (United States)

    Weng, Wan-Yun; Lin, Yu-Ren; She, Hsiao-Ching

    2017-01-01

    The present study investigated the effects of online argumentation scaffolding on students' argumentation involving hypothetical and theoretical biological concepts. Two types of scaffolding were developed in order to improve student argumentation: continuous scaffolding and withdraw scaffolding. A quasi-experimental design was used with four…

  3. Arguing about desirable consequences: what constitutes a convincing argument?

    NARCIS (Netherlands)

    Hoeken, Hans; Timmers, R.H.M.; Schellens, P.J.

    2012-01-01

    Argument quality has consistently been shown to have strong and lasting persuasive effects. The question is what criteria people use to distinguish strong from weak arguments and how these criteria relate to the ones proposed in normative argumentation theory. In an experiment 235 participants witho

  4. Discourse analysis and argumentation theory: the case of television talk

    NARCIS (Netherlands)

    M.A. van Rees

    2007-01-01

    This paper, in discussing the six studies that make up this special issue of the Journal of Pragmatics on argumentation and television talk shows, offers reflections on the relationship between discourse analysis and argumentation theory. First, a brief sketch of both discourse analysis and argument

  5. Complex permeability and permittivity variation of carbonyl iron rubber in the frequency range of 2 to 18 GHz

    Directory of Open Access Journals (Sweden)

    Adriana Medeiros Gama

    2010-04-01

    Full Text Available The complex dielectric permittivity (e and magnetic permeability (m of Radar Absorbing Materials (RAM based on metallic magnetic particles (carbonyl iron particles embedded in a dielectric matrix (silicon rubber have been studied in the frequency range of 2 to 18 GHz. The relative permeability and permittivity of carbonyl iron-silicon composites for various mass fractions are measured by the transmission/reflection method using a vector network analyzer. The concentration dependence of permittivity and permeability on the frequency is analyzed. In a general way, the results show that e´ parameter shows a more significant variation among the evaluated parameters (e”, m”, m’. The comparison of dielectric and magnetic loss tangents (e”/e” and m”/m’, respectively shows more clearly the variation of both parameters (e and m according to the frequency. It is also observed that higher carbonyl iron content fractions favor both dielectric and magnetic loss tangents.

  6. Relative Permittivities for Glucose+Glycine+Water Solution at 278.15 to 313.15 K

    Institute of Scientific and Technical Information of China (English)

    ZHUO Ke-lei; LIU Qian-ge; LIU Hong-xun; LI Na-na; CHEN Yu-juan

    2011-01-01

    The relative permittivities(ε) for the glucose+glycine+water mixtures were measured at temperatures of 278.15 to 313.15 K.The experimental values for a complete data set were critically analyzed.The experimental values were fitted to some empirical equations as the functions of temperature and/or compositions of the solution.At given temperatures and compositions of glycine,the dependences of the relative permittivities on the molar fraction of glucose(Glc) and glycine(Gly) can be described by a linear or quadratic equation,respectively.A comparison of the εGlc values of glucose solution with the εGla values of galactose solution indicates that the relative permittivities of the ternary solutions containing glucose are smaller than those containing galactose under the same conditions.This difference arises from the slight difference in the stereo-structures of the saccharide molecules.

  7. A microcontroller-based microwave free-space measurement system for permittivity determination of lossy liquid materials.

    Science.gov (United States)

    Hasar, U C

    2009-05-01

    A microcontroller-based noncontact and nondestructive microwave free-space measurement system for real-time and dynamic determination of complex permittivity of lossy liquid materials has been proposed. The system is comprised of two main sections--microwave and electronic. While the microwave section provides for measuring only the amplitudes of reflection coefficients, the electronic section processes these data and determines the complex permittivity using a general purpose microcontroller. The proposed method eliminates elaborate liquid sample holder preparation and only requires microwave components to perform reflection measurements from one side of the holder. In addition, it explicitly determines the permittivity of lossy liquid samples from reflection measurements at different frequencies without any knowledge on sample thickness. In order to reduce systematic errors in the system, we propose a simple calibration technique, which employs simple and readily available standards. The measurement system can be a good candidate for industrial-based applications.

  8. An elementary argument for the magnetic field outside a solenoid

    Science.gov (United States)

    Pathak, Aritro

    2017-01-01

    The evaluation of the magnetic field inside and outside a uniform current density infinite solenoid of uniform cross-section is an elementary problem in classical electrodynamics that all undergraduate Physics students study. Symmetry properties of the cylinder and the judicious use of Ampere’s circuital law leads to correct results; however it does not explain why the field is non zero for a finite length solenoid, and why it vanishes as the solenoid becomes infinitely long. An argument is provided in Farley and Price (2001 Am. J. Phys. 69 751), explaining how the magnetic field behaves outside the solenoid and not too far from it, as a function of the length of the solenoid. A calculation is also outlined for obtaining the field just outside the circular cross section solenoid, in the classic text Classical Electrodynamics by Jackson, 3rd edn (John Wiley and Sons, Inc.), problems 5.3-5.5. The purpose of this paper is to provide an elementary argument for why the field becomes negligible as the length of the solenoid is increased. A quantitative analysis is provided for the field outside the solenoid, at radial distances large compared to the linear dimension of the solenoid cross section.

  9. Inviting Argument by Analogy: Analogical-Mapping-Based Comparison Activities as a Scaffold for Small-Group Argumentation

    Science.gov (United States)

    Emig, Brandon R.; McDonald, Scott; Zembal-Saul, Carla; Strauss, Susan G.

    2014-01-01

    This study invited small groups to make several arguments by analogy about simple machines. Groups were first provided training on analogical (structure) mapping and were then invited to use analogical mapping as a scaffold to make arguments. In making these arguments, groups were asked to consider three simple machines: two machines that they had…

  10. On-Line Synchronous Scientific Argumentation Learning: Nurturing Students' Argumentation Ability and Conceptual Change in Science Context

    Science.gov (United States)

    Yeh, Kuan-Hue; She, Hsiao-Ching

    2010-01-01

    The purpose of this study is to examine the difference in effectiveness between two on-line scientific learning programs--one with an argumentation component and one without an argumentation component--on students' scientific argumentation ability and conceptual change. A quasi-experimental design was used in this study. Two classes of 8th grade…

  11. Fostering Learning through the Use of Argumentative Serious Games

    Science.gov (United States)

    Hatzitaskos, Markos; Karacapilidis, Nikos

    As broadly admitted in the related literature, argumentation can promote learning, teamwork and leadership skills. These skills are central to the future of both developed and developing countries; however, related work reveals that students have difficulties in creating logical arguments. Motivated by the above, this paper proposes an innovative learning technology that aims at supporting argumentation through the use of serious games. Serious games have been shown to engage and motivate users and can be built with limited resources in mind. We comment on the suitability of their features for argumentation purposes, and we discuss how their use on teaching argumentation can be beneficial.

  12. Extension of HPL to complex arguments

    Science.gov (United States)

    Maître, Daniel

    2012-03-01

    In this paper we describe the extension of the Mathematica package HPL to treat harmonic polylogarithms of complex arguments. The harmonic polylogarithms have been introduced by Remiddi and Vermaseren [E. Remiddi, J.A.M. Vermaseren, Int. J. Modern Phys. A 15 (2000) 725, hep-ph/9905237] and have many applications in high energy particle physics. New version program summaryProgram title: HPL Catalogue identifier: ADWX_v2_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/ADWX_v2_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 13 610 No. of bytes in distributed program, including test data, etc.: 1 055 706 Distribution format: tar.gz Programming language: Mathematica 7/8. Computer: All computers running Mathematica. Operating system: Operating systems running Mathematica. Supplementary material: Additional "high weight" MinimalSet files available. Classification: 4.7. Catalogue identifier of previous version: ADWX_v1_0 Journal reference of previous version: Comput. Phys. Comm. 174 (2006) 222 Does the new version supersede the previous version?: Yes Nature of problem: Computer algebraic treatment of the harmonic polylogarithms which appear in the evaluation of Feynman diagrams. Solution method: Mathematica implementation. Reasons for new version: Added treatment of complex arguments. Details in arXiv:hep-ph/0703052. Summary of revisions: Added treatment of complex arguments. Details in arXiv:hep-ph/0703052. Running time: A few seconds for each function.

  13. Writing for publication: argument and evidence.

    Science.gov (United States)

    Fahy, Kathleen

    2008-09-01

    The rules for writing a research report for publication are well defined but are much less clear for scholarly scientific papers. The purpose of this paper is to enable new writers to confidently apply the skills of scientific writing within a scholarly paper for publication. Similarities and differences between scientific argument and debating are discussed. Achieving the right 'tone' and emphasis in writing is considered. How to use the correct verb tense is outlined. The importance of a clearly defined question is explained. The elements of an effective scholarly paper are presented and examples given. The elements are the: question, thesis, introduction, body of the paper, conclusion and finally, an abstract.

  14. Theory Reform caused by an Argumentation Tool.

    Science.gov (United States)

    1985-08-13

    caper concerns one such system, called NoteCards. The raier discusses two incidents where using the system uncovered major flaws in the arguments...Navy Personnel R&D Center NTTC (Code 016) San Diego, CA 92152 NAS Memphis (75) Millington, TN 38054 Dr. Barbara Means Human Resources Dr. Richard E...Institute Prcovo, UT 8-:57 Dr. Barbara Hayes-Roth Department of Computer Science Dr. S. ye-::r Stanford University Stanford Un-versity S ta"f r, C A ;33

  15. Mediating argumentative deconstruction of advertising discourses

    DEFF Research Database (Denmark)

    Maier, Carmen Daniela

    exposes how the advertising discourse of various companies is articulated when promoting well known products and services in their commercials. The original advertising discourse is deconstructed and reconstructed with additional visual material in front of the viewers' eyes who are instructed by a voice......-over narrator what to look at and how to identify and decode the persuasive strategies employed. The present multimodal analysis focuses on the characteristic features of these Media Bites argumentative discourses that challenge the legitimacy of the original advertising discourses. Looking specifically...... the deceptive advertising messages.    ...

  16. An Argument for Design Space Reflection

    DEFF Research Database (Denmark)

    Dove, Graham; Halskov, Kim; Hansen, Nicolai Brodersen

    2016-01-01

    We argue that documenting, revisiting and reflecting on the design space of a project provides three important benefits. First it increases our awareness of the constraints introduced by particular design choices. Second, this qualifies our understanding of the way a design space has been filtered...... by design activities. Third we are prompted to challenge these constraints and reconsider disregarded opportunities. To support this argument, we revisit key activities from two projects in our interaction design lab’s portfolio, selected because of the detailed documentation available. We also introduce...

  17. Reasoning about Action: An Argumentation - Theoretic Approach

    CERN Document Server

    Foo, N Y; 10.1613/jair.1602

    2011-01-01

    We present a uniform non-monotonic solution to the problems of reasoning about action on the basis of an argumentation-theoretic approach. Our theory is provably correct relative to a sensible minimisation policy introduced on top of a temporal propositional logic. Sophisticated problem domains can be formalised in our framework. As much attention of researchers in the field has been paid to the traditional and basic problems in reasoning about actions such as the frame, the qualification and the ramification problems, approaches to these problems within our formalisation lie at heart of the expositions presented in this paper.

  18. The argumentative impact of causal relations

    DEFF Research Database (Denmark)

    Nielsen, Anne Ellerup

    1996-01-01

    such as causality, explanation and justification. In certain types of discourse, causal relations also imply an intentional element. This paper describes the way in which the semantic and pragmatic functions of causal markers can be accounted for in terms of linguistic and rhetorical theories of argumentation.......The semantic relations between and within utterances are marked by the use of connectors and adverbials. One type of semantic relations is causal relations expressed by causal markers such as because, therefore, so, for, etc. Some of these markers cover different types of causal relations...

  19. The multimodal argumentation of persuasive counter discourses

    DEFF Research Database (Denmark)

    Maier, Carmen Daniela

    are given prominence in the argumentation by examining their complex interplay and functional differentiation. The ways in which speech, writing and images articulate the counter discourse occupy a central position in the analysis. A special focus is put on the multimodal configuration of specific...... and new multimodal ways of discussing them. References Kress, G. 2010. Multimodality. A Social Semiotic Approach to Contemporary Communication. London: Routledge. Van Leeuwen, Theo. 2008. Discourse and Practice. New Tools for Critical Discourse Analysis. Oxford: Oxford University Press. Chouliaraki, L...

  20. Space-charge-limited leakage current in high dielectric constant and ferroelectric thin films considering the field-dependent permittivity

    Science.gov (United States)

    Sun, J.; Zheng, X. J.; Yin, W.; Tang, M. H.; Li, W.

    2010-12-01

    Distinguishing from the traditional characterization on high-field leakage current density-voltage relationship, the field-dependent permittivity from the polarization derivative is used to solve the space-charge-limited conduction, and the simulated leakage current densities are compared with the previous experimental observations. The influences of the mobility, ferroelectric parameters, and film thickness on the leakage current densities are discussed. The results verify that the high-field quasi-Ohmic region observed experimentally may result from the field-dependent permittivity, and that the leakage current can be influenced by the ferroelectric polarization.

  1. Negative permittivity of ZnO thin films prepared from aluminum and gallium doped ceramics via pulsed-laser deposition

    DEFF Research Database (Denmark)

    Bodea, M. A.; Sbarcea, G.; Naik, G. V.

    2013-01-01

    Aluminum and gallium doped zinc oxide thin films with negative dielectric permittivity in the near infrared spectral range are grown by pulsed laser deposition. Composite ceramics comprising ZnO and secondary phase Al2O3 or Ga2O3 are employed as targets for laser ablation. Films deposited on glass...... from dense and small-grained ceramic targets show optical transmission larger than 70 % in the visible and reveal an onset of metallic reflectivity in the near infrared at 1100 nm and a crossover to a negative real part of the permittivity at approximately 1500 nm. In comparison to noble metals, doped...

  2. The mechanism of the effect of a plasma layer with negative permittivity on the antenna radiation field

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Chunsheng, E-mail: wangcs@hit.edu.cn; Liu, Hui; Jiang, Binhao [Harbin Institute of Technology, Mail Box 402, Harbin 150001 (China); Li, Xueai [Harbin Electric Machinery Company Limited, Harbin 150001 (China)

    2015-06-15

    A model of a plasma–antenna system is developed to study the mechanism of the effect of the plasma layer on antenna radiation. Results show a plasma layer with negative permittivity is inductive, and thus affects the phase difference between electric and magnetic fields. In the near field of antenna radiation, a plasma layer with proper parameters can compensate the capacitivity of the vacuum and enhance the radiation power. In the far field of antenna radiation, the plasma layer with negative permittivity increases the inductivity of the vacuum and reduces the radiation power.

  3. Molding of plasmonic resonances in metallic nanostructures: Dependence of the non-linear electric permittivity on system size and temperature

    KAUST Repository

    Alabastri, A.

    2013-10-25

    In this paper, we review the principal theoretical models through which the dielectric function of metals can be described. Starting from the Drude assumptions for intraband transitions, we show how this model can be improved by including interband absorption and temperature effect in the damping coefficients. Electronic scattering processes are described and included in the dielectric function, showing their role in determining plasmon lifetime at resonance. Relationships among permittivity, electric conductivity and refractive index are examined. Finally, a temperature dependent permittivity model is presented and is employed to predict temperature and non-linear field intensity dependence on commonly used plasmonic geometries, such as nanospheres. 2013 by the authors; licensee MDPI, Basel, Switzerland.

  4. Estimation of permeability tensor and dielectric permittivity of ferrites using a wave guide method under a dc magnetic field

    Directory of Open Access Journals (Sweden)

    Tsiachristos I.

    2014-07-01

    Full Text Available Using a vector network analyzer equipped with a calibrated rectangular wave guide the electric permittivity and the element of the magnetic permeability tensor for Y3Fe5O12, ZnFe2O4 and NiFe2O4 are measured. The electric permittivity can be estimated from the body resonances (d = nλ/2 if a sufficient long sample is used. The estimation of the magnetic permeability tensors’ parameters can be estimated comparing the experimental results with computer simulations using the magnetic properties of the materials as derived from the magnetic measurements.

  5. Numerical simulation of a permittivity probe for measuring the electric properties of planetary regolith

    Science.gov (United States)

    Spitzer, K.; Sohl, F.; Panzner, M.

    2007-08-01

    Measurements of dielectric regolith properties are particularly useful for the detection of subsurface water/ice deposits in various forms, providing important constraints on the volatile content of planetary sub-surfaces and interiors. Additionally, near-surface environmental processes like impact gardening, space weathering, material erosion, vertical mixing, lateral redistribution, and volatile exchange can be addressed more carefully if combined with measurements related to soil stratigraphy and texture. We present a numerical simulation technique that parallels the development of an in-situ probe for measuring electric key properties such as conductivity and permittivity of planetary, asteroid, and cometary regoliths. Our simulation techniques aim at accompanying the hardware development and conduct virtual experiments, e.g., to assess the response of arbitrary heterogeneous conductivity and permittivity distributions or to scrutinize possibilities for spatial reconstruction methods using inverse schemes. In a first step, we have developed a finite element simulation code on the basis of unstructured, adaptive triangular grids for arbitrary two-dimensional axisymmetric distributions of conductivity and permittivity. The code is able to take into account the spatial geometry of the probe and allows for possible inductive effects. In previous studies, the non-inductive approach has been used to convert potential and phase data into apparent material properties. By our simulations, we have shown that this approach is valid for the frequency range from 102 to 107 Hz and electric conductivities of 10-8 S/m typical for planetary regolith.We prove the accuracy of our code to be better than 10% using mixed types of boundary conditions and present a simulated vertical log through a horizontally stratified subsurface layer as a representative example of a heterogeneous distribution of electrical regolith properties. Resolution studies for the given electrode separation

  6. The Whole Point of the Thing: How Nominalisation Might Develop Students' Written Causal Arguments

    Science.gov (United States)

    Carroll, James Edward

    2016-01-01

    Frustrated that previously taught writing frames seemed to impede his A-level students' historical arguments, James Edward Carroll theorised that the inadequacies he identified in their writing were as much disciplinary as stylistic. Drawing on two discourses that are often largely isolated from each other--genre theory and the work of the history…

  7. The simplest formal argument for fitness optimization

    Indian Academy of Sciences (India)

    Alan Grafen

    2008-12-01

    The Formal Darwinism Project aims to provide a formal argument linking population genetics to fitness optimization, which of necessity includes defining fitness. This bridges the gulf between those biologists who assume that natural selection leads to something close to fitness optimization and those biologists who believe on theoretical grounds that there is no sense of fitness that can usefully be said to be optimized. The current paper’s main objective is to provide a careful mathematical introduction to the project, and it also reflects on the project’s scope and limitations. The central argument is the proof of close ties between the mathematics of motion, as embodied in the Price equation, and the mathematics of optimization, as represented by optimization programmes. To make these links, a general and abstract model linking genotype, phenotype and number of successful gametes is assumed. The project has begun with simple dynamic models and simple linking models, and its progress will involve more realistic versions of them. The versions given here are fully mathematically rigorous, but elementary enough to serve as an introduction.

  8. Group decision support using Toulmin argument structures

    Energy Technology Data Exchange (ETDEWEB)

    Janssen, T. [Argonne National Lab., IL (United States)]|[George Mason Univ., Fairfax, VA (United States). School of Information Technology and Engineering; Sage, A.P. [George Mason Univ., Fairfax, VA (United States). School of Information Technology and Engineering

    1996-12-31

    This paper addresses the need for sound science, technology, and management assessment relative to environmental policy decision making through an approach that involves a logical structure for evidence, a framed decision-making process, and an environment that encourages group participation. Toulmin-based logic possesses these characteristics and is used as the basis for development of a group decision support system. This system can support several user groups, such as pesticide policy-making experts, who can use the support system to state arguments for or against an important policy issue, and pest management experts, who can use the system to assist in identifying and evaluating alternatives for controlling pests on agricultural commodities. The resulting decision support system assists in improving the clarity of the lines of reasoning used in specific situations; the warrants, grounds, and backings that are used to support claims and specific lines of reasoning; and the contradictions, rebuttals, and arguments surrounding each step in the reasoning process associated with evaluating a claim or counterclaim. Experts and decisions makers with differing views can better understand each other`s thought processes. The net effect is enhanced communications and understanding of the whole picture and, in many cases, consensus on decisions to be taken.

  9. TE Magnetostatic Surface Waves in Symmetric Dielectric Negative Permittivity Material Waveguide

    Directory of Open Access Journals (Sweden)

    A. I. Ass'ad

    2009-01-01

    Full Text Available Nonlinear magnetostatic surface wave in a slab waveguide structure has been investigated. The design consisted of dielectric film between two thick nonlinear nonmagnetic negative permittivity material (NPM layers. A dispersion relation for TE nonlinear Magnetostatic surface waves (NMSSWs has been derived into the proposed structure and has been numerically investigated. Effective refractive index decreases with thickness and frequency increase have been found. Effective refractive index decrease with optical nonlinearity increase and switching to negative values of effective refractive index at a certain value of optical nonlinearity have been found. This meant that the structure behaved like a left-handed material over certain range. We found that the power flow was changing by changing the operating frequency, the dielectric film thickness, and the optical nonlinearity. Also, the effective refractive index and power flow attained constant values over certain values of dielectric constant values.

  10. Space charge and steady state current in LDPE samples containing a permittivity/conductivity gradient

    DEFF Research Database (Denmark)

    Holbøll, Joachim; Bambery, K. R.; Fleming, R. J.

    2000-01-01

    Electromagnetic theory predicts that a dielectric sample in which a steady DC current of density ε is flowing, and in which the ratio of permittivity ε to conductivity σ varies with position, will acquire a space charge density j·grad(ε/σ). A simple and convenient way to generate an ε/σ gradient...... in a homogeneous sample is to establish a temperature gradient across it. The resulting spatial variation in ε is usually small in polymeric insulators, but the variation in σ can be appreciable. Laser induced pressure pulse (LIPP) measurements were made on 1.5 mm thick plaques of ultra pure LDPE equipped...... with vacuum-evaporated aluminium electrodes. Temperature differences up to 27°C were maintained across the samples, which were subjected to DC fields up to 20 kV/mm. Current density was measured as a function of temperature and field. Negligible thermally generated space charge was observed. The charge...

  11. Plasmonic modulator optimized by patterning of active layer and tuning permittivity

    DEFF Research Database (Denmark)

    Babicheva, Viktoriia; Lavrinenko, Andrei

    2012-01-01

    We study an ultra-compact plasmonic modulator that can be applied in photonic integrated circuits. The modulator is a metal-insulator-metal waveguide with an additional ultra-thin layer of indium tin oxide (ITO). Bias is applied to the multilayer core by means of metal plates that serve...... several optimizations. We examine influence of the ITO permittivity on the modulator's performance and point out appropriate values. We analyze eigenmodes of the waveguide structure and specify the range for its efficient operation. We show that substituting the continuous active layer by a one......-dimension periodic stripes increases transmittance through the device and keeps the modulator's performance at the same level. The dependence on the pattern size and filling factor of the active material is analyzed and optimum parameters are found. Patterned ITO layers allow us to design a Bragg grating inside...

  12. Effective permittivity and permeability of one-dimensional dielectric photonic crystal within a band gap

    Institute of Scientific and Technical Information of China (English)

    Guo Ji-Yong; Chen Hong; Li Hong-Qiang; Zhang Ye-Wen

    2008-01-01

    We take a finite dielectric photonic crystal as a homogeneous slab and have extracted the effective parameters. Our systematic study shows that the effective permittivity or permeability of dielectric photonic crystal is negative within a band gap region. This means that the band gap might act as ε-negative materials (ENMs) with ε0, or μ-negative materials (MNMs) with ε>0 and μ<0. Moreover the effective parameters sensitively rely on size, surface termination, symmetry, etc. The effective parameters can be used to design full transmission tunnelling modes and amplify evanescent wave. Several cases are studied and the results show that dielectric photonic band gap can indeed mimic a single negative material (ENM or MNM) under some restrictions.

  13. Characterizing the complex permittivity of high-κ dielectrics using enhanced field method

    Energy Technology Data Exchange (ETDEWEB)

    Chao, Hsien-Wen; Wong, Wei-Syuan; Chang, Tsun-Hsu, E-mail: thschang@phys.nthu.edu.tw [Department of Physics, National Tsing Hua University, Hsinchu 30024, Taiwan (China)

    2015-11-15

    This paper proposed a method to characterize the complex permittivities of samples based on the enhancement of the electric field strength. The enhanced field method significantly improves the measuring range and accuracy of the samples’ electrical properties. Full-wave simulations reveal that the resonant frequency is closely related to the dielectric constant of the sample. In addition, the loss tangent can be determined from the measured quality factor and the just obtained dielectric constant. Materials with low dielectric constant and very low loss tangent are measured for benchmarking and the measured results agree well with previous understanding. Interestingly, materials with extremely high dielectric constants (ε{sub r} > 50), such as titanium dioxide, calcium titanate, and strontium titanate, differ greatly as expected.

  14. Broadband angle- and permittivity-insensitive nondispersive optical activity based on chiral metamaterials

    CERN Document Server

    Song, Kun; Su, Zhaoxian; Ding, Changlin; Liu, Yahong; Luo, Chunrong; Zhao, Xiaopeng; Bhattarai, Khagendra; Zhou, Jiangfeng

    2016-01-01

    Because of the strong inherent resonances, the giant optical activity obtained via chiral metamaterials generally suffers from high dispersion, which has been a big stumbling block to broadband applications. In this paper, we propose a type of chiral metamaterial consisting of interconnected metal helix structures with four-fold symmetry, which exhibits nonresonant Drude-like response and can therefore avoid the highly dispersive optical activity resulting from resonances. It shows that the well-designed chiral metamaterial can achieve nondispersive and pure optical activity with high transmittance in a broadband frequency range. And the optical activity of multi-layer chiral metamaterials is proportional to the layer numbers of single-layer chiral metamaterial. Most remarkably, the broadband behaviors of nondispersive optical activity and high transmission are insensitive to the incident angles of electromagnetic waves and permittivity of dielectric substrate, thereby enabling more flexibility in polarizatio...

  15. Optical Dispersion, Permittivity Spectrum and Thermal-Lensing Effect in Nickel-Doped Zinc Sulfide Nanoparticles

    Science.gov (United States)

    Abbasi, F.; Koushki, E.; Majles Ara, M. H.; Sahraei, R.

    2017-07-01

    In this paper, Ni-doped ZnS (ZnS:Ni2+) nanoparticles (NPs) have been prepared through a chemical method. The average size of the particle is 45 nm. Thin films of the particles have been prepared by using the spin-coating method. The linear and nonlinear optical properties of Ni-doped ZnS thin films and the colloidal solution of them have been studied widely. Using a precise numerical method, the refractive index curve (dispersion curve), absorption coefficient and optical permittivity of Ni-doped ZnS film have been obtained. Using these values, the absorption coefficient of the colloidal solution of Ni-doped ZnS particles has been simulated and compared with experimental results. Finally, using the z-scan method at low laser irradiation, the thermo-optical effect has been studied and the nonlinear refractive index due to this effect has been reported.

  16. Optically assisted trapping with high-permittivity dielectric rings: Towards optical aerosol filtration

    CERN Document Server

    Alaee, Rasoul; Rockstuhl, Carsten; Passian, Ali

    2016-01-01

    Controlling the transport, trapping, and filtering of nanoparticles is important for many applications. By virtue of their weak response to gravity and their thermal motion, various physical mechanisms can be exploited for such operations on nanoparticles. However, the manipulation based on optical forces is potentially most appealing since it constitutes a highly deterministic approach. Plasmonic nanostructures have been suggested for this purpose, but they possess the disadvantages of locally generating heat and trapping the nanoparticles directly on surface. Here, we propose the use of dielectric rings made of high permittivity materials for trapping nanoparticles. Thanks to their ability to strongly localize the field in space, nanoparticles can be trapped without contact. We use a semi-analytical method to study the ability of these rings to trap nanoparticles. Results are supported by full-wave simulations. Application of the trapping concept to nanoparticle filtration is suggested.

  17. Defect Complex Effect in Nb Doped TiO2 Ceramics with Colossal Permittivity

    Science.gov (United States)

    Li, Fuchao; Shang, Baoqiang; Liang, Pengfei; Wei, Lingling; Yang, Zupei

    2016-10-01

    Donor-doped Nb x Ti1- x O2 ( x = 1%, 2%, 4%, 6%, and 8%) ceramics with giant permittivity (>104) and a very low dielectric loss (˜0.05) were sintered under flowing N2 at 1400°C for 10 h. By increasing Nb doping concentration, two different dielectric responses were evidenced in the frequency dependence of dielectric properties of Nb doped TiO2 ceramics, which corresponded to the space charge polarization and the electron-pinned defect-dipoles effect, respectively. Especially, combined with the x-ray photoelectron spectroscopy results, the electron-pinned defect-dipoles induced by the 2({Nb}^{5 + } )_{{Ti}}^{ bullet } to 4({Ti}^{3 + } )^'_{{Ti}} leftarrow {V}_{{o}}^{ bullet bullet } defect complex were further confirmed to give rise to both their high ɛr and low tan δ in the high frequency range for the Nb x Ti1- x O2 ceramics with x > 4%.

  18. Repulsion of polarised particles from anisotropic materials with a near-zero permittivity component

    Institute of Scientific and Technical Information of China (English)

    Francisco J Rodríguez-Fortu(n)o; Anatoly V Zayats

    2016-01-01

    Reduction of adhesion and stiction is crucial for robust operation on nanomechanical and optofluidic devices as well as atom and molecule behaviour near surfaces.It can be achieved using electric charging,magnetic materials or light pressure and optical trapping.Here we show that a particle scattering or emitting in close proximity to an anisotropic substrate can experience a repulsive force if one of the diagonal components of the permittivity tensor is close to zero.We derive an analytic condition for the existence of such repulsive force depending on the optical properties of the substrate.We also demonstrate the effect using realistic anisotropic metamaterial implementations of a substrate.The anisotropic metamaterial approach using metal-dielectric and graphene-dielectric multilayers provides a tuneable spectral range and a very broad bandwidth of electromagnetic repulsion forces,in contrast to isotropic substrates.

  19. Zero permeability and zero permittivity band gaps in 1D metamaterial photonic crystals

    Energy Technology Data Exchange (ETDEWEB)

    Depine, Ricardo A. [Grupo de Electromagnetismo Aplicado, Departamento de Fisica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, Pabellon I, C1428EHA Buenos Aires (Argentina); Martinez-Ricci, Maria L. [Grupo de Electromagnetismo Aplicado, Departamento de Fisica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, Pabellon I, C1428EHA Buenos Aires (Argentina); Monsoriu, Juan A. [Departamento de Fisica Aplicada, Universidad Politecnica de Valencia, 46022 Valencia (Spain)]. E-mail: jmonsori@fis.upv.es; Silvestre, Enrique [Departamento de Optica, Universidad de Valencia, 46100 Burjassot (Spain); Andres, Pedro [Departamento de Optica, Universidad de Valencia, 46100 Burjassot (Spain)

    2007-04-30

    We consider layered heterostructures combining ordinary positive index materials and dispersive metamaterials. We show that these structures can exhibit a new type of photonic gap around frequencies where either the magnetic permeability {mu} or the electric permittivity {epsilon} of the metamaterial is zero. Although the interface of a semi-infinite medium with zero refractive index (a condition attained either when {mu}=0 or when {epsilon}=0) is known to give full reflectivity for all incident polarizations, here we show that a gap corresponding to {mu}=0 occurs only for TE polarized waves, whereas a gap corresponding to {epsilon}=0 occurs only for TM polarized waves. These band gaps are scale-length invariant and very robust against disorder, although they may disappear for the particular case of propagation along the stratification direction.

  20. On the Definition of Effective Permittivity and Permeability For Thin Composite Layers

    CERN Document Server

    Saenz, E; Ikonen, P; Tretyakov, S; Gonzalo, Ramon; Ikonen, Pekka; Saenz, Elena; Tretyakov, Sergei

    2007-01-01

    The problem of definition of effective material parameters (permittivity and permeability) for composite layers containing only one-two parallel arrays of complex-shaped inclusions is discussed. Such structures are of high importance for the design of novel metamaterials, where the realizable layers quite often have only one or two layers of particles across the sample thickness. Effective parameters which describe the averaged induced polarizations are introduced. As an explicit example, we develop an analytical model suitable for calculation of the effective material parameters $\\epsilon_{\\rm{eff}}$ and $\\mu_{\\rm{eff}}$ for double arrays of electrically small electrically polarizable scatterers. Electric and magnetic dipole moments induced in the structure and the corresponding reflection and transmission coefficients are calculated using the local field approach for the normal plane-wave incidence, and effective parameters are introduced through the averaged fields and polarizations. In the absence of loss...

  1. Complex dielectric permittivity and dielectric relaxation of heavy water along its curve of existence

    Energy Technology Data Exchange (ETDEWEB)

    Nabokov, O.A.; Lyubimov, Yu.A.

    1985-10-01

    The authors previously studied the complex dielectric permittivity of ordinary water at 70-200/sup 0/C. Similar measurements were performed in this work for D/sub 2/O by incomplete filling of a microwave resonator at a frequency of about 9.3 GHz. Distilled 99.8% D/sub 2/O was used. For D/sub 2/O, the value of tau/sub D/T/eta (where eta is the viscosity) increases with increasing temperature, so that at 140/sup 0/C its change goes beyond the limits of error of the measurement of tau/sub D/ and eta. The gradual increase in tau/sub D/T/eta and tau/sub D/D with temperature indicates weakening of the interaction between orientation and translation movements of the liquid D/sub 2/O molecules with increasing temperature. 11 references, 1 figure.

  2. Characterizing the complex permittivity of high-κ dielectrics using enhanced field method

    Science.gov (United States)

    Chao, Hsien-Wen; Wong, Wei-Syuan; Chang, Tsun-Hsu

    2015-11-01

    This paper proposed a method to characterize the complex permittivities of samples based on the enhancement of the electric field strength. The enhanced field method significantly improves the measuring range and accuracy of the samples' electrical properties. Full-wave simulations reveal that the resonant frequency is closely related to the dielectric constant of the sample. In addition, the loss tangent can be determined from the measured quality factor and the just obtained dielectric constant. Materials with low dielectric constant and very low loss tangent are measured for benchmarking and the measured results agree well with previous understanding. Interestingly, materials with extremely high dielectric constants (ɛr > 50), such as titanium dioxide, calcium titanate, and strontium titanate, differ greatly as expected.

  3. Top loaded TM01δ Mode Cylindrical Dielectric Resonator for Complex Permittivity Characterization of Liquids

    Directory of Open Access Journals (Sweden)

    A. Yasin

    2016-12-01

    Full Text Available This paper reports on a technique of using a very high quality factor cylindrical dielectric resonator operating in TM01δ mode to characterize liquids available in trace quantities. The proposed measurement technique is based on the resonant perturbation theory and the resonator is used as a sensor to determine complex permittivity of solvents at 10.5GHz. Owing to a very high unloaded quality factor of about 5000 the proposed sensor can characterize low to medium loss materials with high accuracy. Small quantities of isopropanol and ethanol have been characterized for their solution ratio when mixed with different quantities of distilled water. Low cost and versatility of the proposed structure make it a prime choice for pharmaceutical industry where high standards of purity need to be ensured.

  4. Risk and Argument: A Risk-based Argumentation Method for Practical Security

    NARCIS (Netherlands)

    Nunes Leal Franqueira, V.; Tun, Thein Tan; Yu, Yijun; Wieringa, Roelf J.; Nuseibeh, Bashar

    When showing that a software system meets certain security requirements, it is often necessary to work with formal and informal descriptions of the system behavior, vulnerabilities, and threats from potential attackers. In earlier work, Haley et al. [1] showed structured argumentation could deal

  5. A Dialogic Approach to Argumentation: Using a Chat Room To Develop Early Adolescent Students' Argumentative Writing.

    Science.gov (United States)

    Morgan, Wendy; Beaumont, Glenn

    2003-01-01

    Describes how a teacher and researcher in Australia engaged students in chat-room discussion as a bridge between speaking and writing. Discusses the characteristics of formal written argumentation and recent theoretical reemphasis on its rhetorical and dialogical nature. Describes the classroom strategies devised to develop the students' ability…

  6. Influence of moisture content and temperature on the dielectric permittivity of zeolite NaY.

    Science.gov (United States)

    Kraus, Markus; Kopinke, Frank-Dieter; Roland, Ulf

    2011-03-07

    The influence of moisture content and temperature on the dielectric permittivity (complex resistance) of the zeolite NaY was investigated for a fixed radio frequency (RF) of 13.56 MHz. Sealed glass tubes containing zeolite with defined moisture contents were simultaneously heated in a homogeneous high-frequency electromagnetic field. The dielectric loss factor, i.e. the imaginary part of the permittivity ε(r)″, was calculated from the obtained heating rates. On the basis of the resulting values for various moisture contents and temperatures and utilizing the knowledge of elementary cation hopping processes occurring at low and high frequencies (LF and HF) from the literature, a new model was introduced for the description of dielectric radio-frequency heating of moist zeolites. Since adsorption of water is correlated with an enhancement of the activation energy of the cations on SII sites, cations in the zeolite NaY are moving from SII sites to unoccupied SIII sites when the water content is increasing. Thus, four different transfer processes for the cations have to be considered in total. On the basis of these assumptions, the resulting dielectric loss factor ε(r)″ as a function of water content and temperature for a fixed frequency of 13.56 MHz was modelled. The experimental data are in good agreement with the values obtained from the model. Especially, the measured pronounced maximum of dielectric loss at temperatures below 300 °C and water contents below 4 wt.-% can be explained by the new model.

  7. Public perceptions of arguments supporting and opposing recreational marijuana legalization.

    Science.gov (United States)

    McGinty, Emma E; Niederdeppe, Jeff; Heley, Kathryn; Barry, Colleen L

    2017-02-09

    In debates about recreational marijuana legalization, pro-legalization arguments highlighting economic and other potential policy benefits compete with anti-legalization arguments emphasizing public health risks. In 2016, we conducted a national survey using an online panel (N=979) designed to answer two main research questions: (1) How do Americans perceive the relative strength of competing arguments about recreational marijuana legalization? (2) How are perceptions of argument strength associated with public support for recreational marijuana legalization? We examined differences in attitudes among individuals living in states that have/have not legalized recreational marijuana and among Democrats/Independents/Republicans. Ordered logit regression assessed the relationship between perceived argument strength and public support for recreational marijuana legalization. Respondents rated pro-legalization arguments highlighting beneficial economic and criminal justice consequences as more persuasive than anti-legalization arguments emphasizing adverse public health effects. Respondents were more likely to agree with arguments highlighting legalization's potential to increase tax revenue (63.9%) and reduce prison overcrowding (62.8%) than arguments emphasizing negative consequences on motor vehicle crashes (51.8%) and youth health (49.6%). The highest rated anti-legalization arguments highlighted the conflict between state and federal marijuana laws (63.0%) and asserted that legalization will fail to eliminate the black market (57.2%). Respondents who endorsed pro-legalization economic and criminal justice arguments were more likely than other respondents to support legalization. Our findings indicate that, on both side of the recreational marijuana legalization debate, there are arguments that resonate with the American public. However, public health risk messages were viewed as less compelling than pro-legalization economic and criminal justice-oriented arguments.

  8. Synthesis and characterizations of high permittivity ultraviolet cured soft elastomeric networks and composites applicable as dielectric electroactive polymer

    DEFF Research Database (Denmark)

    Goswami, Kaustav

    siloxane) (PDMS) and polyurethanes are designed with the requirements specific for DEAPs. Thus there is a need to develop elastomers with low elastic modulus, low viscous and dielectric losses and high relative permittivity. Interpenetrating networks and fumed silica reinforced composites of poly...

  9. Association of evaluation methods of the effective permittivity of heterogeneous media on the basis of a generalized singular approximation

    Science.gov (United States)

    Kolesnikov, V. I.; Yakovlev, V. B.; Bardushkin, V. V.; Lavrov, I. V.; Sychev, A. P.; Yakovleva, E. N.

    2013-09-01

    Various methods for evaluation of the effective permittivity of heterogeneous media, namely, the effective medium approximation (Bruggeman's approximation), the Maxwell-Garnett approximation, Wiener's bounds, and the Hashin-Shtrikman variational bounds (for effective static characteristics) are combined on the basis of a generalized singular approximation.

  10. Significantly elevated dielectric permittivity of Si-based semiconductor/polymer 2-2 composites induced by high polarity polymers

    Science.gov (United States)

    Feng, Yefeng; Gong, Honghong; Xie, Yunchuan; Wei, Xiaoyong; Zhang, Zhicheng

    2016-02-01

    To disclose the essential influence of polymer polarity on dielectric properties of polymer composites filled with semiconductive fillers, a series of Si-based semiconductor/polymer 2-2 composites in a series model was fabricated. The dielectric permittivity of composites is highly dependant on the polarity of polymer layers as well as the electron mobility in Si-based semiconductive sheets. The huge dielectric permittivity achieved in Si-based semiconductive sheets after being coated with high polarity polymer layers is inferred to originate from the strong induction of high polarity polymers. The increased mobility of the electrons in Si-based semiconductive sheets coated by high polarity polymer layers should be responsible for the significantly enhanced dielectric properties of composites. This could be facilely achieved by either increasing the polarity of polymer layers or reducing the percolative electric field of Si-based semiconductive sheets. The most promising 2-2 dielectric composite was found to be made of α-SiC with strong electron mobility and poly(vinyl alcohol) (PVA) with high polarity, and its highest permittivity was obtained as 372 at 100 Hz although the permittivity of α-SiC and PVA is 3-5 and 15, respectively. This work may help in the fabrication of high dielectric constant (high-k) composites by tailoring the induction effect of high polarity polymers to semiconductors.

  11. Traceable measurement and imaging of the complex permittivity of a multiphase mineral specimen at micron scales using a microwave microscope.

    Science.gov (United States)

    Gregory, A P; Blackburn, J F; Hodgetts, T E; Clarke, R N; Lees, K; Plint, S; Dimitrakis, G A

    2017-01-01

    This paper describes traceable measurements of the dielectric permittivity and loss tangent of a multiphase material (particulate rock set in epoxy) at micron scales using a resonant Near-Field Scanning Microwave Microscope (NSMM) at 1.2GHz. Calibration and extraction of the permittivity and loss tangent is via an image charge analysis which has been modified by the use of the complex frequency to make it applicable for high loss materials. The results presented are obtained using a spherical probe tip, 0.1mm in diameter, and also a conical probe tip with a rounded end 0.01mm in diameter, which allows imaging with higher resolution (≈10µm). The microscope is calibrated using approach-curve data over a restricted range of gaps (typically between 1% and 10% of tip diameter) as this is found to give the best measurement accuracy. For both tips the uncertainty of scanned measurements of permittivity is estimated to be±10% (at coverage factor k=2) for permittivity ⪝10. Loss tangent can be resolved to approximately 0.001. Subject to this limit, the uncertainty of loss tangent measurements is estimated to be±20% (at k=2). The reported measurements inform studies of how microwave energy interacts with multiphase materials containing microwave absorbent phases.

  12. Correlation between temperature-dependent permittivity dispersion and depolarization behaviours in Zr4+-modified BiFeO3–BaTiO3 piezoelectric ceramics

    Indian Academy of Sciences (India)

    Weidong Zeng; Changrong Zhou; Jianrong Xiao; Jiafeng Ma

    2015-12-01

    The correlation between permittivity frequency dispersion and depoling process upon heating was investigated in Zr4+-modified 0.75BiFeO3–0.25BaTiO3 (BF–BZT) ceramics. The temperature-dependent permittivity r() and the piezoelectric coefficient 33 for poled samples were measured under heating conditions to clarify the depolarization mechanism. The results indicate that the poling temperature plays a crucial role in the domains' alignment process, as expected. The temperature-dependent permittivity frequency dispersion and depolarization behaviours may have same origin. The aligned domains' break up into random state/nanodomains at depoling temperature ( d), which causes strong frequency dependence of the permittivity, simultaneously, induces the loss of piezoelectricity. It suggests that the temperature-dependent permittivity measurements method is a simple way to determine the depolarization temperature.

  13. Using Computer-Assisted Argumentation Mapping to develop effective argumentation skills in high school advanced placement physics

    Science.gov (United States)

    Heglund, Brian

    Educators recognize the importance of reasoning ability for development of critical thinking skills, conceptual change, metacognition, and participation in 21st century society. There is a recognized need for students to improve their skills of argumentation, however, argumentation is not explicitly taught outside logic and philosophy---subjects that are not part of the K-12 curriculum. One potential way of supporting the development of argumentation skills in the K-12 context is through incorporating Computer-Assisted Argument Mapping to evaluate arguments. This quasi-experimental study tested the effects of such argument mapping software and was informed by the following two research questions: 1. To what extent does the collaborative use of Computer-Assisted Argumentation Mapping to evaluate competing theories influence the critical thinking skill of argument evaluation, metacognitive awareness, and conceptual knowledge acquisition in high school Advanced Placement physics, compared to the more traditional method of text tables that does not employ Computer-Assisted Argumentation Mapping? 2. What are the student perceptions of the pros and cons of argument evaluation in the high school Advanced Placement physics environment? This study examined changes in critical thinking skills, including argumentation evaluation skills, as well as metacognitive awareness and conceptual knowledge, in two groups: a treatment group using Computer-Assisted Argumentation Mapping to evaluate physics arguments, and a comparison group using text tables to evaluate physics arguments. Quantitative and qualitative methods for collecting and analyzing data were used to answer the research questions. Quantitative data indicated no significant difference between the experimental groups, and qualitative data suggested students perceived pros and cons of argument evaluation in the high school Advanced Placement physics environment, such as self-reported sense of improvement in argument

  14. Low-loss NiZnCo ferrite processed at low sintering temperature with matching permeability and permittivity for miniaturization of VHF-UHF antennas

    Science.gov (United States)

    Zheng, Zongliang; Feng, Quanyuan; Xiang, Qianyin; Di, Zhixiong; Harris, Vincent G.

    2017-02-01

    Spinel ferrites of a nominal composition of Ni0.5Zn0.3Co0.2Fe2O4 (NiZnCo) with various B2O3-Bi2O3-SiO2-ZnO (BBSZ) glass additions were successfully synthesized at a relatively low temperature of 930 °C for their potential applications as magneto-dielectric antenna substrate materials. Measurements of magnetic and dielectric properties show that, with an increasing content of BBSZ from 0 to 2 wt. %, the permeability μ' at low frequencies was increased from ˜4.7 to ˜8.9, whereas the permittivity ɛ' was improved from ˜5.9 to ˜12.5. These tunable permeability and permittivity were proved to be closely related to the grain size and density, based on the magnetic circuit model and effective medium theory. Importantly, the sample with 0.5 wt. % addition demonstrated the optimal magneto-dielectric performance with nearly equivalent values of μ' and ɛ', which yields a large miniaturization factor of ˜6.5 and the normalized impedance of ˜1 over the frequency range of 10 MHz-1 GHz. Moreover, this sample exhibits low loss characteristics over a wide frequency range, where the dielectric loss tan δɛ is in the order of 10-3 and the magnetic loss tan δμ is less than 0.15. These properties make the ferrite material a promising candidate for miniaturized antennas with good impedance matched to free space and open a great potential for low-temperature co-fired ceramic applications toward the practical fabrication and high integration of the antennas.

  15. A Theological Argument for an Everett Multiverse

    CERN Document Server

    Page, Don N

    2012-01-01

    Science looks for the simplest hypotheses to explain observations. Starting with the simple assumption that {\\em the actual world is the best possible world}, I sketch an {\\it Optimal Argument for the Existence of God}, that the sufferings in our universe would not be consistent with its being alone the best possible world, but the total world could be the best possible if it includes an omnipotent, omniscient, omnibenevolent God who experiences great value in creating and knowing a universe with great mathematical elegance, even though such a universe has suffering. God seems loathe to violate elegant laws of physics that He has chosen to use in His creation, such as Maxwell's equations for electromagnetism or Einstein's equations of general relativity for gravity within their classical domains of applicability, even if their violation could greatly reduce human suffering (e.g., from falls). If indeed God is similarly loathe to violate quantum unitarity (though such violations by judicious collapses of the w...

  16. Irony as a Communicative and Argumentative Strategy

    Directory of Open Access Journals (Sweden)

    Ida Lucia Machado

    2014-06-01

    Full Text Available This article draws upon the polyphonic theory of Bakhtin (1970a, 1970b as well as certain concepts utilized by Ducrot (1984, showing, in the field of a theory of discourse analysis — in this case, Charaudeau’s semiolinguistics (1983, 1992, 2008 — some procedures which lead to the construction of irony. The study takes into account that this linguistic phenomenon appears as a means of communication susceptible to the creation of argumentative strategies even if the latter are not presented in a non-conventional way. To illustrate this, the study uses, as a basis for reflection, excerpts from the memoirs or life narrative of a French artist whose form of writing, according to Bakhtin (1970b, may fall into the category of Carnival literature.

  17. The multimodal argumentation of persuasive counter discourses

    DEFF Research Database (Denmark)

    Maier, Carmen Daniela

    with the characteristics and potential fallacies of the advertising discourse of commercials. The original advertising discourse is deconstructed and reconstructed with additional visual material in front of the viewers’ eyes who are instructed by a voiceover narrator what to look at and how to identify and decode...... and critical participants in the process of message understanding. In this paper, I explore the Media Bites videos that identify and discuss problematic gender issues in commercials advertising various products. I adopt a multimodal approach in my discourse analysis and I establish which semiotic modes...... are given prominence in the argumentation by examining their complex interplay and functional differentiation. The ways in which speech, writing and images articulate the counter discourse occupy a central position in the analysis. A special focus is put on the multimodal configuration of specific...

  18. On multiple zeta values of even arguments

    Energy Technology Data Exchange (ETDEWEB)

    Hoffmann, Michael E. [U.S. Naval Academy, Annapolis, MD (United States). Dept. of Mathematics; Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany)

    2012-06-15

    For k {<=} n, let E(2n,k) be the sum of all multiple zeta values with even arguments whose weight is 2n and whose depth is k. Of course E(2n,1) is the value {zeta}(2n) of the Riemann zeta function at 2n, and it is well known that E(2n,2)=(3)/(4){zeta}(2n). Recently Z. Shen and T. Cai gave formulas for E(2n,3) and E(2n,4) in terms {zeta}(2n) and {zeta}(2){zeta}(2n-2). We give two formulas form E(2n,k), both valid for arbitrary k{<=}n, one of which generalizes the Shen-Cai results; by comparing the two we obtain a Bernoulli-number identity. We also give an explicit generating function for the numbers E(2n,k).

  19. Foundations of Academic Freedom: Making New Sense of Some Aging Arguments

    Science.gov (United States)

    Andreescu, Liviu

    2009-01-01

    The article distinguishes between the various arguments traditionally offered as justifications for the principle of academic freedom. Four main arguments are identified, three consequentialist in nature (the argument from truth, the democratic argument, the argument from autonomy), and one nonconsequentialist (a variant of the autonomy argument).…

  20. A Measure of Perceived Argument Strength: Reliability and Validity.

    Science.gov (United States)

    Zhao, Xiaoquan; Strasser, Andrew; Cappella, Joseph N; Lerman, Caryn; Fishbein, Martin

    2011-03-04

    Studies of the content of persuasive messages in which the central arguments of the message are scrutinized have traditionally relied on the technique of thought-listing to assess argument strength. Although the validity of the thought-listing procedure is well documented, its utility can be limited in situations involving non-adult populations and sensitive topics. In this paper we present a self-reported scale that can be used to assess perceived argument strength in contexts where thought-listing may be less appropriate. This scale taps into perceived argument strength from multiple points of view, including but also extending beyond the potential of the argument to elicit positive and negative thoughts. Reliability and validity of this scale were assessed in health communication contexts involving anti-drug PSAs directed at adolescents and anti-smoking PSAs targeting adults. Evidence of convergence between this scale and the thought-listing technique was also obtained using the classical comprehensive exam arguments.

  1. Microwave effective permittivity of carbon black filled polymers: Comparison of mixing law and effective medium equation predictions

    Science.gov (United States)

    El Bouazzaoui, S.; Achour, M. E.; Brosseau, C.

    2011-10-01

    Carbon black (CB) filled polymers have become the platform to study a number of interesting properties including percolation mechanisms, localization effects, and multiscale modeling of interface and interphase regions surrounding filler particles. A systematic microwave study of the effective complex permittivity of CB filled diglycidylic ether of bisphenol A based epoxy samples, determined by the impedance bridge (35 GHz) and the cavity perturbation (2.4 and 9.5 GHz) techniques, is reported. A series of composite materials was fabricated by mechanical mixing with three types of CB (Monarch and Sterling) particles differing with their average particle size and surface area. On the basis of the limited experimental evidence presented here, our distinctive features are seen in the data: (i) We found no enhancement of the effective permittivity near the dc percolation threshold; (ii) the calculation of the effective permittivity based on Lichteneker and Rother's mixing law with constant k close to zero reproduces the measured CB volume fraction dependence of the effective permittivity very well for the series of samples containing Monarch particles, (iii) the data are not well fit with the Bruggeman equation for supercolative samples. This is an indication that a mean field model is not strictly applicable because this simple model assumes a given microstructure for the composite material; and (iv) the two exponent phenomenological percolation equation (TEPPE) can yield good predictive values of the imaginary part of the effective complex permittivity over the range of frequencies and CB volume fractions with non-universal values of the percolation exponents. It is concluded that fitting the experimental data with mixing law and effective medium equation predictions has limited applicability because these models assume a given microstructure for the composite material.

  2. Argumentation meets adapted cognition: manipulation in media discourse on immigration

    OpenAIRE

    Hart, Christopher

    2013-01-01

    Critical discourse analysis has focussed extensively on argumentation in anti-immigration discourse where a specific suite of argumentation strategies has been identified as constitutive of the discourse. The successful perlocutionary effects of these arguments are analysed as products of pragmatic processes based on ‘common-sense’ reasoning schemes known as topoi. In this paper, I offer an alternative explanation grounded in cognitive-evolutionary psychology. Specifically, it is shown that a...

  3. Improving EFL argumentative writing: A dialogic critical thinking approach

    OpenAIRE

    Mansoor Fahim; Mostafa Mirzaii

    2013-01-01

    ELT has traditionally practiced the teaching of argumentative writing through conventional writing instruction and as such has disregarded critical thinking, a capability essential to argumentative writing. The present study, therefore, aimed at enhancing EFL argumentative writing through the coupling of writing instruction and dialogic critical thinking. To this aim, 48 Iranian EFL learners, selected through cluster sampling, were randomly assigned to either the experimental group―receiving ...

  4. Attitude and argumentation: an analysis of secondary school writing production

    OpenAIRE

    Abreu,Adriana Rodrigues de; Adriana Nogueira Accioly NÓBREGA

    2015-01-01

    This article aims at discussing argumentation in secondary school writing production considering resources of attitude, which may create writers’ authorial positioning (HYLAND, 2012). The study focuses on Systemic-Functional Linguistics (HALLIDAY; HASAN, 1989; HALLIDAY, 1994; HALLIDAY; MATTHIESSEN, 2004), in particular on the Appraisal System (MARTIN; WHITE, 2005), in interface with a social perspective of argumentation (BRETON, 2003). Two argumentative texts are analyzed through a qualitativ...

  5. Smoking Cues, Argument Strength, and Perceived Effectiveness of Antismoking PSAs

    Science.gov (United States)

    Cappella, Joseph. N.; Lerman, Caryn; Strasser, Andrew A.

    2011-01-01

    Introduction: The study examines the effectiveness of antismoking public service announcements (PSAs) among adult smokers as a function of smoking cues and the argument strength of the PSAs. Consistent with the previous cue-reactivity studies, smoking cues are defined as one of the following visual scenes: (a) objects associated with smoking, (b) holding or handling cigarettes, and (c) actual smoking behaviors. Argument strength indicates smoker's judgments of perceived strength and persuasiveness of the arguments extracted from the PSAs. Methods: Data were collected through a web-based experiment of a random sample of general population of smokers (n = 566 adults aged 19 years or older). Each participant was shown 4 PSAs randomly selected from a set of 60. Data were analyzed using multilevel modeling to assess the effects of smoking cues and argument strength. Effectiveness measures include perceived persuasiveness, transportation, valenced thought, negative emotion, and smoking-related thoughts. Results: Argument strength is a significant predictor of outcome variables. Although there were no significant main effects of smoking cues on any outcome variables, smoking cues were found to interact with argument strength such that the association between argument strength and outcome variables became weaker for PSAs in the smoking cue condition compared with those in the no-cue condition. Conclusions: The interaction between smoking cues and argument strength suggests that smoking cues in antismoking PSAs undermine a significant part of what makes PSAs effective—their arguments against smoking. In designing antismoking messages, the inclusion of smoking cues should be weighed carefully. PMID:21330273

  6. Response to 'Fear of death and the symmetry argument'

    Directory of Open Access Journals (Sweden)

    Natalja Deng

    Full Text Available ABSTRACT This article is a response to 'Fear of death and the symmetry argument', in this issue. In that article, the author discusses the above Lucretian symmetry argument, and proposes a view that justifies the existing asymmetry in our attitudes towards birth and death. I begin by distinguishing this symmetry argument from a different one, also loosely inspired by Lucretius, which also plays a role in the article. I then describe what I take to be the author's solution to the original symmetry argument (i.e. the one above and explain why I am unpersuaded by it.

  7. Constructional Approach as Compared with Projectionist Approach to Argument Structure

    Institute of Scientific and Technical Information of China (English)

    戴好运

    2016-01-01

    Projectionist accounts of argument structure give verb's semantic representation a central role in sentence interpretation, it is held that the argument structure and alternations related with a verb are always the product of its semantic representation. However, a circularity problem arises. To solve this problem, Goldberg (1995)'s constructional approach proposed that argument structure patterns are linguistic units in their own right. This paper attempts to make a comparison between projectionist approach and constructional approach to argument structure and discuss constructional approach's advantage in reducing verb senses and avoiding circularity.

  8. Fregego krytyka dowodu ontologicznego (FREGE'S CRITICISM OF THE ONTOLOGICAL ARGUMENT

    Directory of Open Access Journals (Sweden)

    Arkadiusz Gut

    2005-06-01

    Full Text Available The paper reconstructs Frege's criticism of the ontological argument for the existence of God on the basis of various remarks scattered in his writings. The material is organized in such a way as to: (a reveal a logical structure of the argument; (b show and discern various presupposition of a logical, semantical and ontological character; and (c indicate some essential weaknesses of the ontological argument. It is argued that Frege's critical commentaries on this argument are essentially connected to four solutions, stating that: (1 the difference between a name and a predicate is categorical; (2 the existential judgement possesses a different logical structure than the singular judgement; (3 in the characteristic of concepts marks and properties should be distinguished; (4 the ascription of number contains the statement about a concept. In order to make Frege's argumentation as understandable as possible it is confronted with Kant's criticism of ontological argument. The analysis carried on in the above-described way reveals a number of shortcomings which discredit the ontological argument. For example, the paper shows that the analysis of predication of oneness (Einzigkeit does not lead to the affirmation of God's existence. Moreover, it shows that in that argument the term God is used in two different semantic roles; that some theses that should constitute the argument's conclusion, are already assumed; and that sense-condition and truth-conditions are not distinguished.Other author's publications:

  9. Preface: From Pragmatics and Dialectics to Argument Studies

    Directory of Open Access Journals (Sweden)

    Budzynska Katarzyna

    2014-03-01

    Full Text Available Pragmatics and dialectics are two disciplines which have been amongst the first and most important partners for argument studies in the exploration of the complex realm of communication. Treating argumentation as a construct consisting of premises and conclusion allows for investigating some interesting properties of the phenomenon of reasoning, but does not capture a variety of aspects related to the usage of natural language and dialogical context in which real-life argumentation is typically embedded. This special issue explores some of the fascinating research questions which emerge when we move beyond logic into the territory of the pragmatics and dialectics of argument.

  10. News Coverage of Sugar-Sweetened Beverage Taxes: Pro- and Antitax Arguments in Public Discourse

    Science.gov (United States)

    Gollust, Sarah E.; Jarlenski, Marian P.; Nathanson, Ashley M.; Barry, Colleen L.

    2013-01-01

    Objectives. We examined news coverage of public debates about large taxes on sugar-sweetened beverages (SSBs) to illuminate how the news media frames the debate and to inform future efforts to promote obesity-related public policy. Methods. We conducted a quantitative content analysis in which we assessed how frequently 30 arguments supporting or opposing SSB taxes appeared in national news media and in news outlets serving jurisdictions where SSB taxes were proposed between January 2009 and June 2011. Results. News coverage included more discrete protax than antitax arguments on average. Supportive arguments about the health consequences and financial benefits of SSB taxes appeared most often. The most frequent opposing arguments focused on how SSB taxes would hurt the economy and how they constituted inappropriate governmental intrusion. Conclusions. News outlets that covered the debate on SSB taxes in their jurisdictions framed the issue in largely favorable ways. However, because these proposals have not gained passage, it is critical for SSB tax advocates to reach audiences not yet persuaded about the merits of this obesity prevention policy. PMID:23597354

  11. Analysis of Discourse Markers in Chinese Students’ Argumentative Speech Chinese Students’ Argumentative Speech

    Institute of Scientific and Technical Information of China (English)

    QU; Jingwen; WANG; Yongli; DING; Shaojun

    2015-01-01

    DMs are a set of lexical and non-lexical forms which commonly appear in communication.Rather than other researches who focus on discourse markers in natural English speaking context,this paperexamines Chinese students’ usage of DMs in argumentative speeches and indicates that proper use of discourse markers could facilitate the communication process and more attention should be given to learning and teaching discourse markers by both students and teachers.

  12. The Dielectric Permittivity of Crystals in the reduced Hartree-Fock approximation

    CERN Document Server

    Cancès, Eric

    2009-01-01

    In a recent article (Canc\\`es, Deleurence and Lewin, Commun. Math. Phys., 281 (2008), pp. 129-177), we have rigorously derived, by means of bulk limit arguments, a new variational model to describe the electronic ground state of insulating or semiconducting crystals in the presence of local defects. In this so-called reduced Hartree-Fock model, the ground state electronic density matrix is decomposed as $\\gamma = \\gamma^0_{\\rm per} + Q_{\

  13. Reconstruction of Vertical Profile of Permittivity of Layered Media which is Probed Using Vertical Differential Antenna

    Science.gov (United States)

    Pochanin, Gennadiy P.; Poyedinchuk, Anatoliy Y.; Varianytsia-Roshchupkina, Liudmyla A.; Pochanina, Iryna Ye.

    2016-04-01

    Results of this research are intended to use at GPR investigations of layered media (for example, at roads' inspection) for the processing of collected data and reconstruction of dependence of permittivity on the depth. Recently, an antenna system with a vertical differential configuration of receiving module (Patent UA81652) for GPR was suggested and developed The main advantage of the differential antennas in comparison with bistatic antennas is a high electromagnetic decoupling between the transmitting and receiving modules. The new vertical differential configuration has an additional advantage because it allows collecting GPR data reflected by layered media without any losses of information about these layers [1] and, potentially, it is a more accurate instrument for the layers thickness measurements [2]. The developed antenna system is tested in practice with the GPR at asphalt thickness measurements [3] and shown an accuracy which is better than 0.5 cm. Since this antenna system is good for sounding from above the surface (air coupled technique), the mobile laboratory was equipped with the developed GPR [3]. In order to process big set of GPR data that collected during probing at long routes of the roads, for the data processing it was tested new algorithm of the inverse problem solution. It uses a fast algorithm for calculation of electromagnetic wave diffraction by non-uniform anisotropic layers [4]. The algorithm is based on constructing a special case solution to the Riccati equation for the Cauchy problem and enables a qualitative description of the wave diffraction by the electromagnetic structure of the type within a unitary framework. At this stage as initial data we used synthetic GPR data that were obtained as results of the FDTD simulation of the problem of UWB electromagnetic impulse diffraction on layered media. Differential and bistatic antenna configurations were tested at several different profiles of permittivity. Meanings of permittivity of

  14. Multifrequency permittivity measurements enable on-line monitoring of changes in intracellular conductivity due to nutrient limitations during batch cultivations of CHO cells.

    Science.gov (United States)

    Ansorge, Sven; Esteban, Geoffrey; Schmid, Georg

    2010-01-01

    Lab and pilot scale batch cultivations of a CHO K1/dhfr(-) host cell line were conducted to evaluate on-line multifrequency permittivity measurements as a process monitoring tool. The beta-dispersion parameters such as the characteristic frequency (f(C)) and the permittivity increment (Deltaepsilon(max)) were calculated on-line from the permittivity spectra. The dual-frequency permittivity signal correlated well with the off-line measured biovolume and the viable cell density. A significant drop in permittivity was monitored at the transition from exponential growth to a phase with reduced growth rate. Although not reflected in off-line biovolume measurements, this decrease coincided with a drop in OUR and was probably caused by the depletion of glutamine and a metabolic shift occurring at the same time. Sudden changes in cell density, cell size, viability, capacitance per membrane area (C(M)), and effects caused by medium conductivity (sigma(m)) could be excluded as reasons for the decrease in permittivity. After analysis of the process data, a drop in f(C) as a result of a fall in intracellular conductivity (sigma(i)) was identified as responsible for the observed changes in the dual-frequency permittivity signal. It is hypothesized that the beta-dispersion parameter f(C) is indicative of changes in nutrient availability that have an impact on intracellular conductivity sigma(i). On-line permittivity measurements consequently not only reflect the biovolume but also the physiological state of mammalian cell cultures. These findings should pave the way for a better understanding of the intracellular state of cells and render permittivity measurements an important tool in process development and control.

  15. Two Studies Examining Argumentation in Asynchronous Computer Mediated Communication

    Science.gov (United States)

    Joiner, Richard; Jones, Sarah; Doherty, John

    2008-01-01

    Asynchronous computer mediated communication (CMC) would seem to be an ideal medium for supporting development in student argumentation. This paper investigates this assumption through two studies. The first study compared asynchronous CMC with face-to-face discussions. The transactional and strategic level of the argumentation (i.e. measures of…

  16. Improving Undergraduates' Argumentative Group Essay Writing through Self-Assessment

    Science.gov (United States)

    Fung, Yong Mei; Mei, Hooi Chee

    2015-01-01

    When writing an argumentative essay, writers develop and evaluate arguments to embody, initiate, or simulate various kinds of interpersonal and textual interaction for reader consideration (Wu & Allison, 2003). This is quite challenging for English as a second language (ESL) learners. To improve the quality of their writing, students need to…

  17. Validity Arguments for Diagnostic Assessment Using Automated Writing Evaluation

    Science.gov (United States)

    Chapelle, Carol A.; Cotos, Elena; Lee, Jooyoung

    2015-01-01

    Two examples demonstrate an argument-based approach to validation of diagnostic assessment using automated writing evaluation (AWE). "Criterion"®, was developed by Educational Testing Service to analyze students' papers grammatically, providing sentence-level error feedback. An interpretive argument was developed for its use as part of…

  18. From arguments to constraints on a Bayesian network

    NARCIS (Netherlands)

    Bex, F.J.; Renooij, S.

    2016-01-01

    In this paper, we propose a way to derive constraints for a Bayesian Network from structured arguments. Argumentation and Bayesian networks can both be considered decision support techniques, but are typically used by experts with different backgrounds. Bayesian network experts have the mathematical

  19. A formal account of complex argumentation in a critical discussion

    NARCIS (Netherlands)

    Visser, J.; Mohammed, D.; Lewiński, M.

    2013-01-01

    In this paper, I present a dialogue game approach to the argumentation stage of a critical discussion. This formal perspective on the pragma-dialectical ideal model is meant to facilitate a contribution of pragma-dialectical theorising to the field of argumentation and computation. The dialogue game

  20. Using History and Philosophy of Science to Promote Students' Argumentation

    Science.gov (United States)

    Archila, Pablo Antonio

    2015-01-01

    This article describes the effect of a teaching-learning sequence (TLS) based on the discovery of oxygen in promoting students' argumentation. It examines the written and oral arguments produced by 63 high school students (24 females and 39 males, 16-17 years old) in France during a complete TLS supervised by the same teacher. The data used in…

  1. Argupolis: a doctoral program on argumentation practices in different contexts

    NARCIS (Netherlands)

    van Eemeren, F.H.; Greco Morasso, S.; Grossen, M.; Perret-Clermont, A.-N.; Rigotti, E.

    2009-01-01

    Argumentation is a form of communicative interaction by means of which social realities - institutions, groups and relationships - are construed and managed. People develop argumentation in numerous purposeful activities: to make sound and well-thought decisions, to critically found their opinions,

  2. Learning about Plate Tectonics through Argument-Writing

    Science.gov (United States)

    Klein, Perry D.; Samuels, Boba

    2010-01-01

    In a quasi-experimental study (N = 60), grade 7/8 teachers students were taught to write arguments in content-area subjects. After instruction, students drew on document portfolios to write on a new topic: "Do the continents drift?" In a MANCOVA, students who participated in argument instruction scored significantly higher than a control…

  3. Semiotic and Theoretic Control in Argumentation and Proof Activities

    Science.gov (United States)

    Arzarello, Ferdinando; Sabena, Cristina

    2011-01-01

    We present a model to analyze the students' activities of argumentation and proof in the graphical context of Elementary Calculus. The theoretical background is provided by the integration of Toulmin's structural description of arguments, Peirce's notions of sign, diagrammatic reasoning and abduction, and Habermas' model for rational behavior.…

  4. Memory, Critical Theory and the Argument from History.

    Science.gov (United States)

    Cox, J. Robert

    1990-01-01

    Explores the function of memory in critical theory, particularly in the work of Herbert Marcuse, as the basis for a critical argumentation. Argues that Marcuse's view suggests that argument is a "re-membering" of what had been split asunder--reason, imagination, and the capacity of action. Discusses other implications of Marcuse's stance. (PRA)

  5. The Effect of Authority on the Persuasiveness of Mathematical Arguments

    Science.gov (United States)

    Inglis, Matthew; Mejia-Ramos, Juan Pablo

    2009-01-01

    Three experiments are reported that investigate the extent to which an authority figure influences the level of persuasion undergraduate students and research-active mathematicians invest in mathematical arguments. We demonstrate that, in some situations, both students and researchers rate arguments as being more persuasive when they are…

  6. Analogy and Intersubjectivity: Political Oratory, Scholarly Argument and Scientific Reports.

    Science.gov (United States)

    Gross, Alan G.

    1983-01-01

    Focuses on the different ways political oratory, scholarly argument, and scientific reports use analogy. Specifically, analyzes intersubjective agreement in Franklin D. Roosevelt's First Inaugural address, the scholarly argument between Sir Karl Popper and Thomas S. Kuhn, and the scientific reports of various mathematicians and scientists. (PD)

  7. Argumentation: A Forgotten Object of Research in Mexico

    Directory of Open Access Journals (Sweden)

    Luis Antonio Monzón Laurencio

    2011-11-01

    Full Text Available Argumentation has been, since the beginnings of Western culture, a fundamental tool of thought, and part of the university studies that today face many challenges, some of which require the development of this skill. However, in Mexico, research on this subject is practically nonexistent. This article briefly discusses the state-of-the-art research on argumentation in Latin America.

  8. Argumentation in Secondary School Students' Structured and Unstructured Chat Discussions

    Science.gov (United States)

    Salminen, Timo; Marttunen, Miika; Laurinen, Leena

    2012-01-01

    Joint construction of new knowledge demands that persons can express their statements in a convincing way and explore other people's arguments constructively. For this reason, more knowledge on different means to support collaborative argumentation is needed. This study clarifies whether structured interaction supports students' critical and…

  9. Concepts and Contexts – Argumentative Forms of Framing

    DEFF Research Database (Denmark)

    Gabrielsen, Jonas; Nørholm Just, Sine; Bengtsson, Mette

    2011-01-01

    , and it is necessary to determine what argumentative forms the concept of framing actually covers. In this paper we argue that framing refers to at least two different argumentative forms. One is an internal definition of the concepts in question; the other is an external shift in the context of the case. In making...

  10. Memory, Critical Theory and the Argument from History.

    Science.gov (United States)

    Cox, J. Robert

    1990-01-01

    Explores the function of memory in critical theory, particularly in the work of Herbert Marcuse, as the basis for a critical argumentation. Argues that Marcuse's view suggests that argument is a "re-membering" of what had been split asunder--reason, imagination, and the capacity of action. Discusses other implications of Marcuse's…

  11. Regulatory Evolution and Theoretical Arguments in Evolutionary Biology

    Science.gov (United States)

    Ioannidis, Stavros

    2013-01-01

    The "cis"-regulatory hypothesis is one of the most important claims of evolutionary developmental biology. In this paper I examine the theoretical argument for "cis"-regulatory evolution and its role within evolutionary theorizing. I show that, although the argument has some weaknesses, it acts as a useful example for the importance of current…

  12. Viewing a Poem as Argument: Helping Students Understand Contemporary Poetry

    Science.gov (United States)

    Bauer, Sara

    2008-01-01

    When high school honors students were put off by contemporary poetry, the author engaged them by analyzing the poem as an "argument." Using the Toulmin model to establish a warrant, advance a claim, and locate details to support that claim, students were able, by treating a poem as an argument, to increase their understanding of the…

  13. Perceptions of the Qualities of Written Arguments by Japanese Students

    Science.gov (United States)

    Suzuki, Shinobu

    2011-01-01

    This study examines how Japanese students perceive the qualities of written arguments that were constructed to have different forms. Based on the theoretical dimensions of verbal communication styles that Gudykunst and Ting-Toomey (1988) proposed, the research questions asked whether the respondents would perceive direct arguments to be of higher…

  14. Learning about Plate Tectonics through Argument-Writing

    Science.gov (United States)

    Klein, Perry D.; Samuels, Boba

    2010-01-01

    In a quasi-experimental study (N = 60), grade 7/8 teachers students were taught to write arguments in content-area subjects. After instruction, students drew on document portfolios to write on a new topic: "Do the continents drift?" In a MANCOVA, students who participated in argument instruction scored significantly higher than a control class on…

  15. Teaching the Academic Argument in a University EFL Environment

    Science.gov (United States)

    Bacha, Nahla Nola

    2010-01-01

    An educational challenge that many university EFL students face is the production of written academic arguments as part of their required essays. Although the importance of argumentative writing in education is uncontested, and research shows that EFL students find difficulties in producing such texts, it is not adequately dealt with for the L1…

  16. "Argument!" Helping Students Understand What Essay Writing Is About

    Science.gov (United States)

    Wingate, Ursula

    2012-01-01

    Argumentation is a key requirement of the essay, which is the most common genre that students have to write. However, how argumentation is realised in disciplinary writing is often poorly understood by academic tutors, and therefore not adequately taught to students. This paper presents research into undergraduate students' concepts of argument…

  17. Teaching and Learning Argumentation in English: A Dialogic Approach

    Science.gov (United States)

    VanDerHeide, Jennifer; Juzwik, Mary; Dunn, Mandie

    2016-01-01

    Various instructional approaches have been laid out for conceptualizing argumentation talk and writing in English classrooms. One prominent, and historically durable, approach is formalist--teachers slot the teaching of argument into a form-based approach, usually using the 5-paragraph theme. This model too often fails to persuade students of the…

  18. Viewing the study of argumentation as normative pragmatics

    NARCIS (Netherlands)

    van Eemeren, F.H.; Garssen, B.; Capone, A.; Lo Piparo, F.; Carapezza, M.

    2013-01-01

    In this chapter we explain that the pragma-dialectical approach to argumentation involves at the same time a pragmatic and a critical treatment of argumentative discourse. Starting from the speech act dimension of pragmatics, we indicate for each of the five components of the pragma-dialectical rese

  19. First Steps in Teaching Argumentation: A South African Study

    Science.gov (United States)

    Braund, Martin; Scholtz, Zena; Sadeck, Melanie; Koopman, Robert

    2013-01-01

    South African student teachers were studied to see how they coped with requirements to teach science using argumentation. Lesson observations, plans, reflective logs, post-teaching interviews and assessment of pupils' argumentation were used to compare student teachers' preparedness and interactions with pupils. Two clusters of students were…

  20. The handicap principle and the argument of subversion from within

    DEFF Research Database (Denmark)

    Baron, Christian

    2013-01-01

    This paper examines the very disparate positions that various actors have taken towards the argument of subversion from within (a classical argument against the evolution of altruism by group selection) in a set of related debates on group selection, altruism and the handicap principle. Using thi...

  1. Rap and Technology Teach the Art of Argument

    Science.gov (United States)

    Fink, Rosalie

    2017-01-01

    How can teachers integrate rap and technology strategies to teach students with learning disabilities the art of persuasive argument writing? This teacher research study presents creative new approaches for teaching argument writing. Strategies used in the study helped college freshmen with learning disabilities (LD) succeed in developing…

  2. Learning about Plate Tectonics through Argument-Writing

    Science.gov (United States)

    Klein, Perry D.; Samuels, Boba

    2010-01-01

    In a quasi-experimental study (N = 60), grade 7/8 teachers students were taught to write arguments in content-area subjects. After instruction, students drew on document portfolios to write on a new topic: "Do the continents drift?" In a MANCOVA, students who participated in argument instruction scored significantly higher than a control…

  3. Analogy and Intersubjectivity: Political Oratory, Scholarly Argument and Scientific Reports.

    Science.gov (United States)

    Gross, Alan G.

    1983-01-01

    Focuses on the different ways political oratory, scholarly argument, and scientific reports use analogy. Specifically, analyzes intersubjective agreement in Franklin D. Roosevelt's First Inaugural address, the scholarly argument between Sir Karl Popper and Thomas S. Kuhn, and the scientific reports of various mathematicians and scientists. (PD)

  4. Semiotic and Theoretic Control in Argumentation and Proof Activities

    Science.gov (United States)

    Arzarello, Ferdinando; Sabena, Cristina

    2011-01-01

    We present a model to analyze the students' activities of argumentation and proof in the graphical context of Elementary Calculus. The theoretical background is provided by the integration of Toulmin's structural description of arguments, Peirce's notions of sign, diagrammatic reasoning and abduction, and Habermas' model for rational behavior.…

  5. Science Teachers and Scientific Argumentation: Trends in Views and Practice

    Science.gov (United States)

    Sampson, Victor; Blanchard, Margaret R.

    2012-01-01

    Current research indicates that student engagement in scientific argumentation can foster a better understanding of the concepts and the processes of science. Yet opportunities for students to participate in authentic argumentation inside the science classroom are rare. There also is little known about science teachers' understandings of…

  6. Arguments completed in suit over Internet censorship.

    Science.gov (United States)

    1996-05-31

    Closing remarks on the Communications Decency Act, requiring Internet providers to censor materials that may be unsuitable for minors, were heard on May 10, 1996. The American Civil Liberties Union (ACLU) is leading the challenge to the law. Because information about HIV necessarily must deal with sexual practices, HIV/AIDS service providers would be forced to either avoid talking about the subject or find ways to prevent minors from accessing the information. During the oral arguments, U.S. Justice Department attorney Anthony Coppolino tried to show that the Internet is more like a broadcast medium such as television or radio and is different from newspapers, which enjoy a constitutional protection against government censorship. ACLU attorney Christopher Hansen disagreed, saying the reverse is true. The ACLU said parental control mechanisms such as SurfWatch, Net Nanny, and Cyberpatrol are commercially available to parents who wish to restrict their children's Internet access and are more effective than the government's proposal. The court is expected to rule on the lawsuit in several weeks. An appeal to the U.S. Supreme Court is expected, regardless of the outcome.

  7. The flaw in the firewall argument

    CERN Document Server

    Mathur, Samir D

    2014-01-01

    A lot of confusion surrounds the issue of black hole complementarity, because the question has been considered without discussing the mechanism which guarantees unitarity. Considering such a mechanism leads to the following: (1) The Hawking quanta with energy E of order the black hole temperature T carry information, and so only appropriate processes involving E>>T quanta can have any possible complementary description with an information-free horizon; (2) The stretched horizon describes all possible black hole states with a given mass M, and it must expand out to a distance s_{bubble} before it can accept additional infalling bits; (3) The Hawking radiation has a very particular low temperature T, and infalling quanta interact significantly with it only within a distance s_{alpha} of the horizon. One finds s_{alpha} >T, and this removes the argument against complementarity recently made by Almheiri et al. In particular, the condition E>>T leads to the notion of 'fuzzball complementarity', where the modes aro...

  8. The flaw in the firewall argument

    Energy Technology Data Exchange (ETDEWEB)

    Mathur, Samir D., E-mail: mathur.16@osu.edu; Turton, David, E-mail: turton.7@osu.edu

    2014-07-15

    A lot of confusion surrounds the issue of black hole complementarity, because the question has been considered without discussing the mechanism which guarantees unitarity. Considering such a mechanism leads to the following: (1) The Hawking quanta with energy E of order the black hole temperature T carry information, and so only appropriate processes involving E≫T quanta can have any possible complementary description with an information-free horizon; (2) The stretched horizon describes all possible black hole states with a given mass M, and it must expand out to a distance s{sub bubble} before it can accept additional infalling bits; (3) The Hawking radiation has a specific low temperature T, and infalling quanta interact significantly with it only within a distance s{sub α} of the horizon. One finds s{sub α}≪s{sub bubble} for E≫T, and this removes the argument against complementarity recently made by Almheiri et al. In particular, the condition E≫T leads to the notion of ‘fuzzball complementarity’, where the modes around the horizon are indeed correctly entangled in the complementary picture to give the vacuum.

  9. Influence of particle arrangement on the permittivity of an elastomeric composite

    Science.gov (United States)

    Tsai, Peiying J.; Nayak, Suchitra; Ghosh, Suvojit; Puri, Ishwar K.

    2017-01-01

    Elastomers are used as dielectric layers contained between the parallel conductive plates of capacitors. The introduction of filler particles into an elastomer changes its permittivity ɛ. When particle organization in a composite is intentionally varied, this alters its capacitance. Using numerical simulations, we examine how conductive particle chains introduced into polydimethylsiloxane (PDMS) alter ɛ. The effects of filler volume fraction ψ, interparticle d and interchain spacing a, zigzag angle θ between adjacent particles and overall chain orientation, particle size r, and clearance h between particles and the conductive plates are characterized. When filler particles are organized into chainlike structures rather than being just randomly distributed in the elastomer matrix, ɛ increases by as much as 85%. When particles are organized into chainlike forms, ɛ increases with increasing ψ and a, but decreases with increasing d and θ. A composite containing smaller particles has a higher ɛ when ψ <9 % while larger particles provide greater enhancement when ψ is larger than that value. To enhance ɛ, adjacent particles must be interconnected and the overall chain direction should be oriented perpendicular to the conductive plates. These results are useful for additive manufacturing on electrical applications of elastomeric composites.

  10. Yttrium scandate thin film as alternative high-permittivity dielectric for germanium gate stack formation

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Cimang, E-mail: cimang@adam.t.u-tokyo.ac.jp; Lee, Choong Hyun; Nishimura, Tomonori; Toriumi, Akira [Department of Materials Engineering, The University of Tokyo, 7-3-1 Hongo, Tokyo 113-8656 (Japan); JST, CREST, 7-3-1 Hongo, Tokyo 113-8656 (Japan)

    2015-08-17

    We investigated yttrium scandate (YScO{sub 3}) as an alternative high-permittivity (k) dielectric thin film for Ge gate stack formation. Significant enhancement of k-value is reported in YScO{sub 3} comparing to both of its binary compounds, Y{sub 2}O{sub 3} and Sc{sub 2}O{sub 3}, without any cost of interface properties. It suggests a feasible approach to a design of promising high-k dielectrics for Ge gate stack, namely, the formation of high-k ternary oxide out of two medium-k binary oxides. Aggressive scaling of equivalent oxide thickness (EOT) with promising interface properties is presented by using YScO{sub 3} as high-k dielectric and yttrium-doped GeO{sub 2} (Y-GeO{sub 2}) as interfacial layer, for a demonstration of high-k gate stack on Ge. In addition, we demonstrate Ge n-MOSFET performance showing the peak electron mobility over 1000 cm{sup 2}/V s in sub-nm EOT region by YScO{sub 3}/Y-GeO{sub 2}/Ge gate stack.

  11. Complex permittivity and conductivity of poly(-phenylenediazomethine) and its blends at microwave frequencies

    Indian Academy of Sciences (India)

    K G Princy; Rani Joseph; Honey John; K T Mathew

    2010-06-01

    Poly(-phenylenediazomethine) was synthesized by the condensation reaction between glyoxal and -phenylene diamine in different solvents like methanol, toluene, -cresol and ,-dimethylformamide. The dielectric properties and microwave conductivity of the pelletized samples were measured using cavity perturbation technique. The measurements were done at 2.17 GHz at room temperature (25°C). The effect of dopants on the dielectric properties and conductivity was studied using HCl and HClO4. Dielectric properties like dielectric constant, dielectric loss factor and microwave conductivity increased on doping with HCl and HClO4. Conducting polymer composites were prepared by in situ polymerization of glyoxal and -phenylenediamine in different solvents containing different amounts of PVC, and silica. The microwave conductivity and complex permittivity of each sample was measured. The effect of dopants like HClO4 and HCl on these dielectric properties was also studied. The d.c. conductivity of the pressed samples measured by the two-probe method was also studied.

  12. Obstacle-based self-calibration techniques for the determination of the permittivity of liquids

    Directory of Open Access Journals (Sweden)

    I. Rolfes

    2007-06-01

    Full Text Available In this contribution, different obstacle-based self-calibration techniques for the measurement of the dielectric properties of liquids are investigated at microwave frequencies. The liquid under test is contained inside a waveguide, which is connected to the ports of a vector network analyzer. The permittivity of the liquid is characterized on the basis of the measured scattering parameters.

    In order to extract the material parameters precisely and to eliminate systematic errors of the setup, calibration measurements have to be performed. For this purpose, different self-calibration methods based on the displacement of an obstacle are considered. The presented methods differ in that way, that either transmission and reflection measurements or purely reflection measurements are performed. All these methods have in common that the material parameters are already calculable within a so-called self-calibration procedure. Thus, a full two-port calibration of the whole setup is not necessary. Furthermore, the methods can be realized effectively in a practical setup having the advantage that a rearrangement of the setup is not needed for the material parameter measurements and that the liquid under investigation can pass continuously through the measurement cell. This might be of interest for the application in an industrial process, enabling the continuous flow of the material while the parameter characterization can take place at the same time.

  13. Tunable Mixed Ionic/Electronic Conductivity and Permittivity of Graphene Oxide Paper for Electrochemical Energy Conversion.

    Science.gov (United States)

    Bayer, Thomas; Bishop, Sean R; Perry, Nicola H; Sasaki, Kazunari; Lyth, Stephen M

    2016-05-11

    Graphene oxide (GO) is a two-dimensional graphitic carbon material functionalized with oxygen-containing surface functional groups. The material is of interest in energy conversion, sensing, chemical processing, gas barrier, and electronics applications. Multilayer GO paper has recently been applied as a new proton conducting membrane in low temperature fuel cells. However, a detailed understanding of the electrical/dielectric properties, including separation of the ionic vs electronic contributions under relevant operating conditions, has so far been lacking. Here, the electrical conductivity and dielectric permittivity of GO paper are investigated in situ from 30 to 120 °C, and from 0 to 100% relative humidity (RH) using impedance spectroscopy. These are related to the water content, measured by thermogravimetric analysis. With the aid of electron blocking measurements, GO is demonstrated to be a mixed electronic-protonic conductor, and the ion transference number is derived for the first time. For RH > 40%, conductivity is dominated by proton transport (with a maximum of 0.5 mS/cm at 90 °C and 100% RH). For RH proton conducting electrolyte but also as a mixed conducting electrode material under appropriate conditions. Such materials are highly applicable in electrochemical energy conversion and storage devices such as fuel cells and electrolyzers.

  14. Charge-transfer dynamics and nonlocal dielectric permittivity tuned with metamaterial structures as solvent analogues

    Science.gov (United States)

    Lee, Kwang Jin; Xiao, Yiming; Woo, Jae Heun; Kim, Eunsun; Kreher, David; Attias, André-Jean; Mathevet, Fabrice; Ribierre, Jean-Charles; Wu, Jeong Weon; André, Pascal

    2017-07-01

    Charge transfer (CT) is a fundamental and ubiquitous mechanism in biology, physics and chemistry. Here, we evidence that CT dynamics can be altered by multi-layered hyperbolic metamaterial (HMM) substrates. Taking triphenylene:perylene diimide dyad supramolecular self-assemblies as a model system, we reveal longer-lived CT states in the presence of HMM structures, with both charge separation and recombination characteristic times increased by factors of 2.4 and 1.7--that is, relative variations of 140 and 73%, respectively. To rationalize these experimental results in terms of driving force, we successfully introduce image dipole interactions in Marcus theory. The non-local effect herein demonstrated is directly linked to the number of metal-dielectric pairs, can be formalized in the dielectric permittivity, and is presented as a solid analogue to local solvent polarity effects. This model and extra PH3T:PC60BM results show the generality of this non-local phenomenon and that a wide range of kinetic tailoring opportunities can arise from substrate engineering. This work paves the way toward the design of artificial substrates to control CT dynamics of interest for applications in optoelectronics and chemistry.

  15. Complex permittivity and complex permeability of Sr ions substituted Ba ferrite at X-band

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Charanjeet [Department of Electronics Technology, Guru Nanak Dev University, Amritsar, Punjab (India); Bindra Narang, S. [Department of Electronics Technology, Guru Nanak Dev University, Amritsar, Punjab (India)], E-mail: sukhleen2@yahoo.com; Hudiara, I.S. [Department of Electronics Technology, Guru Nanak Dev University, Amritsar, Punjab (India); Sudheendran, K.; James Raju, K.C. [School of Physics, Central University Hyderabad, Andhra Pradesh (India)

    2008-05-15

    M-type hexagonal ferrite composition, Ba{sub (1-x)}Sr{sub x}Fe{sub 12}O{sub 19} (x=0.0, 0.2, 0.4, 0.6, 0.8 and 1.0), was prepared by a two route ceramic method. Complex permittivity ({epsilon}'-j{epsilon}'') and complex permeability ({mu}'-j{mu}'') have been measured using a network analyzer from 8.2 to 12.4 GHz X-ray diffraction confirmed the M-type hexagonal structure and a scanned electron micrograph was used to analyze the grain size distribution of ferrite. Substitution of Sr{sup 2+} ions causes an increase in porosity that deteriorates the electromagnetic and microstructural properties in the doped samples. Both dielectric constant and dielectric loss are enhanced in comparison to the permeability and magnetic loss over the entire frequency region. This is due to a resistivity variation and the formation of Fe{sup 2+} ions, which increases the hopping mechanism between Fe{sup 2+} and Fe{sup 3+} ions.

  16. Complex permittivity, permeability and microwave absorbing properties of Co–Ti substituted strontium hexaferrite

    Directory of Open Access Journals (Sweden)

    Bindra Narang Sukhleen

    2016-03-01

    Full Text Available M-type strontium ferrite with compositions SrFe(12-2xCoxTixO19 (x = 0.0, 0.3, 0.5, 0.7, 1.0, were prepared by two route ceramic method. The effects of Co–Ti substitution on their microstructure, electromagnetic properties, and microwave absorptive behavior were analyzed. The complex permittivity (∊′-j∊″ and complex permeability (μ′-jμ″ have been measured from 8.2 to 12.4 GHz using a network analyzer. Scanning electron microscope was used to analyze the grain size distribution and porosity of the ferrite. X-ray diffraction confirmed the M-type structure of the doped strontium ferrite. Vibrating sample magnetometer was used to study hysteresis loop of the ferrite. This study suggests that the control of grain size, decrease in coercivity and enhanced values of dielectric constant and loss are effective means to improve microwave absorption. The dielectric constant and loss were enhanced in comparison to the permeability constant and loss over the entire frequency range.

  17. Frequency dispersive complex permittivity and permeability of ferromagnetic metallic granular composite at microwave frequencies

    Energy Technology Data Exchange (ETDEWEB)

    Chen Ping, E-mail: chenping@nju.edu.cn [School of Electronic Science and Engineering, Nanjing University, Nanjing 210093 (China); Liu Min; Wang Ling; Poo Yin; Wu Ruixin [School of Electronic Science and Engineering, Nanjing University, Nanjing 210093 (China)

    2011-12-15

    We experimentally studied the frequency dependent complex permittivity {epsilon} and permeability {mu} of composite composed of carbonyl iron powder (CIP) and epoxy resin in the frequency range 1-18 GHz. We found that the intrinsic {epsilon} and {mu} of CIP extracted from the measured {epsilon} and {mu} of composites follow the classical Maxwell equations and the Landau-Lifshitz-Gilbert (LLG) equation, respectively. The dependences of {epsilon} and {mu} of composites on the volume fraction of CIP (vf{sub CIP}) were investigated using the two-exponent phenomenological percolation equation (TEPPE). We found that the TEPPE can fit the experimental results very well. Comparing the results of percolation parameters derived by experimental data at different frequencies, we show that the TEPPE is frequency independent for the composites at microwave frequencies. The results also show that the {epsilon} and {mu} spectrums of composites with definite vf{sub CIP} can be correctly calculated by combining the TEPPE with the theoretical models of intrinsic {epsilon} and {mu}. - Highlights: > Study on frequency dispersive properties of carbonyl iron/resin composite at 1-18 GHz. > Intrinsic properties of carbonyl iron particles were extracted and analyzed. > Effective properties of the composite were correctly described by the Mclachlan formula. > The Mclachlan formula was proved to be invariable versus frequency for dispersion mediums.

  18. Relative Permittivity and Conductivity of Water-treed Region in XLPE Estimated by an Equivalent Circuit

    Science.gov (United States)

    Ozaki, Tamon; Ito, Noriyuki; Kawai, Jiro; Nakamura, Shuhei

    By dividing a water-treed XLPE sheet sample of 1 mm thickness into a non-degraded region and a water-treed one, relative permittivity εr2' and ac conductivity σAC2 of the water-treed region have been estimated using an equivalent circuit. The way of changes of εr2' and σAC2 with the length r of the water-treed region has been discussed based on the Sillars model. It has been concluded that the volume fraction of water in the water-treed layer is in the range of 0.5 % to 1.5 % for the most-degraded XLPE sheet, which depends on the ratio of axes of spheroids to which water-filled voids and channels are compared. It is also concluded that ac conductivity of water in the water-treed region is in the range of 3×10-3 S/m to 2×10-2 S/m.

  19. Influence of particle arrangement on the permittivity of an elastomeric composite

    Directory of Open Access Journals (Sweden)

    Peiying J. Tsai

    2017-01-01

    Full Text Available Elastomers are used as dielectric layers contained between the parallel conductive plates of capacitors. The introduction of filler particles into an elastomer changes its permittivity ε. When particle organization in a composite is intentionally varied, this alters its capacitance. Using numerical simulations, we examine how conductive particle chains introduced into polydimethylsiloxane (PDMS alter ε. The effects of filler volume fraction ψ, interparticle d and interchain spacing a, zigzag angle θ between adjacent particles and overall chain orientation, particle size r, and clearance h between particles and the conductive plates are characterized. When filler particles are organized into chainlike structures rather than being just randomly distributed in the elastomer matrix, ε increases by as much as 85%. When particles are organized into chainlike forms, ε increases with increasing ψ and a, but decreases with increasing d and θ. A composite containing smaller particles has a higher ε when ψ<9% while larger particles provide greater enhancement when ψ is larger than that value. To enhance ε, adjacent particles must be interconnected and the overall chain direction should be oriented perpendicular to the conductive plates. These results are useful for additive manufacturing on electrical applications of elastomeric composites.

  20. Temperature characterization of dielectric permittivity and AC conductivity of nano copper oxide-doped polyaniline composite

    Science.gov (United States)

    Shubha, L. N.; Madhusudana Rao, P.

    2016-06-01

    The polyaniline/copper oxide (PANI/CuO) nanocomposite was prepared by mixing solutions of polyaniline and copper oxide nanoparticles in dimethyl sulfoxide (DMSO). The synthesized polymer nanocomposites were characterized by X-ray powder diffraction (XRD), scanning electron microscope (SEM) and UV-visible spectroscopy. The characteristic peaks in XRD and UV-visible spectra confirmed the presence of CuO in the polymer structure. SEM images indicated morphological changes in the composite matrix as compared to the pristine PANI. The DC conductivity measurements were performed using two-probe method for various temperatures. AC conductivity and dielectric response of the composites were investigated in the frequency range of 102-106Hz using LCR meter. Dielectric permittivity ɛ‧(w) and dielectric loss factor ɛ‧‧(w) were investigated. It was observed that ɛ‧(w) and ɛ‧‧(w) decrease with increase in frequency at all temperatures. At a particular frequency it is observed that both ɛ‧(w) and ɛ‧‧(w) increase with increase in temperature. It was also observed that AC conductivity increased with increase in frequency and temperature.

  1. Observation of reduction in Casimir force without change of dielectric permittivity

    CERN Document Server

    Banishev, A A; Castillo-Garza, R; Klimchitskaya, G L; Mostepanenko, V M; Mohideen, U

    2012-01-01

    Additional information is provided on the effect of the significant (up to 35%) reduction in the magnitude of the Casimir force between an Au-coated sphere and an indium tin oxide film which was observed after UV treatment of the latter. A striking feature of this effect is that the reduction is not accompanied with a corresponding variation of the dielectric permittivity, as confirmed by direct ellipsometry measurements. The measurement data are compared with computations using the Lifshitz theory. It is shown that the data for the untreated sample are in a very good agreement with theory taking into account the free charge carriers in the indium tin oxide. The data for the UV-treated sample exclude the theoretical results obtained with account of free charge carriers. These data are found to be in a very good agreement with theory disregarding the free charge carriers in an indium tin oxide film. A possible theoretical explanation of our observations as a result of phase transition of indium tin oxide from ...

  2. Voltage-stabilised elastomers with increased relative permittivity and high electrical breakdown strength by means of phase separating binary copolymer blends of silicone elastomers

    DEFF Research Database (Denmark)

    A Razak, Aliff Hisyam; Yu, Liyun; Skov, Anne Ladegaard

    2017-01-01

    Increased electrical breakdown strength and increased dielectric permittivity of silicone-based dielectric elastomers are achieved by means of the addition of so-called voltage-stabilisers prepared from PDMS–PPMS copolymers as well as PDMS–PEG copolymers in order to compensate for the negative...... effect of softness on electrical stability of silicone elastomers. The voltage-stabilised elastomer, incorporating a high-permittivity PDMS–PEG copolymer, possesses increased relative permittivity, high electrical breakdown strength, excellent network integrity and low dielectric loss and paves the way...... towards specialised silicone elastomers for dielectric elastomer transducer products with inherent softness and electrical stability, and thus increased actuation at a given voltage....

  3. Improving EFL argumentative writing: A dialogic critical thinking approach

    Directory of Open Access Journals (Sweden)

    Mansoor Fahim

    2013-05-01

    Full Text Available ELT has traditionally practiced the teaching of argumentative writing through conventional writing instruction and as such has disregarded critical thinking, a capability essential to argumentative writing. The present study, therefore, aimed at enhancing EFL argumentative writing through the coupling of writing instruction and dialogic critical thinking. To this aim, 48 Iranian EFL learners, selected through cluster sampling, were randomly assigned to either the experimental group―receiving writing instruction in conjunction with doing tasks involving dialogic critical thinking―or the control group, only receiving writing instruction. To compare the writing performances of the two groups, a pretest prior to the treatment and a posttest after the treatment were administered, both in the form of in-class 180-word four-paragraph argumentative essays within a time limit of 30 minutes. While both groups made statistically significant improvements in writing argumentatively, the results indicated that the coalescence of writing instruction and dialogic critical thinking led to superior performances.

  4. A Canonical Approach to the Argument/Adjunct Distinction

    Directory of Open Access Journals (Sweden)

    Diana Forker

    2014-01-01

    Full Text Available This paper provides an account of the argument/adjunct distinction implementing the 'canonical approach'. I identify five criteria (obligatoriness, latency, co-occurrence restrictions, grammatical relations, and iterability and seven diagnostic tendencies that can be used to distinguish canonical arguments from canonical adjuncts. I then apply the criteria and tendencies to data from the Nakh-Daghestanian language Hinuq. Hinuq makes extensive use of spatial cases for marking adjunct-like and argument-like NPs. By means of the criteria and tendencies it is possible to distinguish spatial NPs that come close to canonical arguments from those that are canonical adjuncts, and to place the remaining NPs bearing spatial cases within the argument-adjunct continuum.

  5. Formal Assurance Arguments: A Solution In Search of a Problem?

    Science.gov (United States)

    Graydon, Patrick J.

    2015-01-01

    An assurance case comprises evidence and argument showing how that evidence supports assurance claims (e.g., about safety or security). It is unsurprising that some computer scientists have proposed formalizing assurance arguments: most associate formality with rigor. But while engineers can sometimes prove that source code refines a formal specification, it is not clear that formalization will improve assurance arguments or that this benefit is worth its cost. For example, formalization might reduce the benefits of argumentation by limiting the audience to people who can read formal logic. In this paper, we present (1) a systematic survey of the literature surrounding formal assurance arguments, (2) an analysis of errors that formalism can help to eliminate, (3) a discussion of existing evidence, and (4) suggestions for experimental work to definitively answer the question.

  6. Concepts and Contexts – Argumentative Forms of Framing

    DEFF Research Database (Denmark)

    Gabrielsen, Jonas; Nørholm Just, Sine; Bengtsson, Mette

    2011-01-01

    The notion of framing has become central in the field of argumentation. The question is, however, what we gain from studying the process of argumentation through framing, since framing is itself a broad concept in need of specification. Different traditions understand the term differently......, and it is necessary to determine what argumentative forms the concept of framing actually covers. In this paper we argue that framing refers to at least two different argumentative forms. One is an internal definition of the concepts in question; the other is an external shift in the context of the case. In making...... this argument we combine theories of framing with the classical rhetorical theory of the stases, more precisely status definitio and status translatio. Our focus is primarily theoretical, but we illustrate our points by means of examples taken from public debates on the value of real estate....

  7. Time domain reflectometry-measuring dielectric permittivity to detect soil non-acqeous phase liquids contamination-decontamination processes

    Directory of Open Access Journals (Sweden)

    A. Comegna

    2013-09-01

    Full Text Available Contamination of soils with non-aqueous phase liquids (NAPL constitutes a serious geo-environmental problem, given the toxicity level and high mobility of these organic compounds. To develop effective decontamination methods, characterisation and identification of contaminated soils are needed. The objective of this work is to explore the potential of dielectric permittivity measurements to detect the presence of NAPLs in soils. The dielectric permittivity was measured by Time Domain Reflectometry method (TDR in soil samples with either different volumetric content of water (w and NAPL (NAPL or at different stages during immiscible displacement test carried out with two different flushing solutions. A mixing model proposed by Francisca and Montoro, was calibrated to estimate the volume fraction of contaminant present in soil. Obtained results, showed that soil contamination with NAPL and the monitoring of immiscible fluid displacement, during soil remediation processes, can be clearly identified from dielectric measurements.

  8. High-dielectric-permittivity high-elasticity three-component nanocomposites with low percolation threshold and low dielectric loss

    Science.gov (United States)

    Dang, Zhi-Min; Xia, Bing; Yao, Sheng-Hong; Jiang, Mei-Juan; Song, Hong-Tao; Zhang, Li-Qun; Xie, Dan

    2009-01-01

    Three-component high-elasticity nanocomposites consisting of methyl vinyl silicone rubber (VMQ) and nanosized barium titanate (BT) and carbon black (CB) were fabricated. Studies on dielectric property and elastic modulus of the CB-BT/VMQ nanocomposites showed that the composites had a low percolation threshold (fc=0.0355) due to the use of nanosized CB, and the maximum of dielectric permittivity was 960 at 103 Hz with a low dielectric loss (0.04). When the concentration of CB was close to fc, the dielectric permittivity was sensitive to the change in temperature. The present dielectric properties and excellent elasticity would satisfy the need in practical applications, especially in some fields of cable accessories and heat sensitive sensors.

  9. Analysis on effect of low dielectric permittivity on indium-doped tin oxide based optically transparent terahertz patch antenna

    Science.gov (United States)

    Thampy, Anand Sreekantan; Darak, Mayur Sudesh; Dhamodharan, Sriram Kumar

    2016-09-01

    Indium-doped tin oxide based optically transparent rectangular patch antennas are designed to resonate at 750 GHz; one on the glass substrate and the other on the polyimide substrate. Characteristics of both the transparent antennas such as impedance bandwidth, radiation efficiency, directivity and gain are analyzed and compared. Polyimide substrate has a lower dielectric permittivity than the glass substrate. The effect of low dielectric permittivity substrate on the radiation characteristics of the terahertz transparent patch antenna is analyzed. The transparent antenna on polyimide substrate is shown to have gain greater than 3.97dB in 714-795 GHz. The proposed transparent antennas are designed and simulated by using finite element method based electromagnetic solver, Ansys-HFSS.

  10. An X-Band Waveguide Measurement Technique for the Accurate Characterization of Materials with Low Dielectric Loss Permittivity

    CERN Document Server

    Allen, Kenneth W; Reid, David R; Bean, Jeffrey A; Ellis, Jeremy D; Morris, Andrew P; Marsh, Jeramy M

    2016-01-01

    In this work, we present a new X-band waveguide (WR90) measurement method that permits the broadband characterization of the complex permittivity for low dielectric loss tangent material specimens with improved accuracy. An electrically-long polypropylene specimen that partially fills the cross-section is inserted into the waveguide and the transmitted scattering parameter (S21) is measured. The extraction method relies on computational electromagnetic simulations, coupled with a genetic algorithm, to match the experimental S21 measurement. The sensitivity of the technique to sample length was explored by simulating specimen lengths from 2.54 to 15.24 cm, in 2.54 cm increments. Analysis of our simulated data predicts the technique will have the sensitivity to measure loss tangent values on the order of 10e-3 for materials such as polymers with relatively low real permittivity values. The ability to accurately characterize low-loss dielectric material specimens of polypropylene is demonstrated experimentally. ...

  11. Control of gigahertz permeability and permittivity dispersion by means of nanocrystallization in FeCo based nanocrystalline alloy

    Science.gov (United States)

    Han, Mangui; Lu, Haipeng; Deng, Longjiang

    2010-11-01

    An amorphous (FeCo) based alloy has been prepared by a rapid quench method. Subsequent annealing on the amorphous samples gives rise to the coexistence of two magnetic phases: amorphous matrix and nanocrystalline grains (α'-FeCo) with an average size of 9.8 nm. Permeability dispersion behaviors have been studied by Kittel theory [C. Kittel, J. Phys. Radium 12, 332 (1951)]. The results show that these two magnetic phases contribute to the permeability dispersion. The Cole-Cole dispersion law [K. S. Cole and R. H. Cole, J. Chem. Phys. 9, 341 (1941)] has been employed to explain the permittivity dispersion within microwave region based on the assumption that multiple dielectric relaxation processes existing. Our results indicate the possibility of tuning the high frequency permeability and permittivity values of (FeCo) based alloy by controlling the magnetic microstructure, which suggests an alternative method to develop smart electromagnetic materials.

  12. Optimizing the Drude-Lorentz model for material permittivity: Method, program, and examples for gold, silver, and copper

    Science.gov (United States)

    Sehmi, H. S.; Langbein, W.; Muljarov, E. A.

    2017-03-01

    Approximating the frequency dispersion of the permittivity of materials with simple analytical functions is of fundamental importance for understanding and modeling the optical response of materials and resulting structures. In the generalized Drude-Lorentz model, the permittivity is described in the complex frequency plane by a number of simple poles having complex weights, which is a physically relevant and mathematically simple approach: By construction, it respects causality, represents physical resonances of the material, and can be implemented easily in numerical simulations. We report here an efficient method of optimizing the fit of measured data with the Drude-Lorentz model having an arbitrary number of poles. We show examples of such optimizations for gold, silver, and copper, for different frequency ranges and up to four pairs of Lorentz poles taken into account. We also provide a program implementing the method for general use.

  13. Low temperature sintered giant dielectric permittivity CaCu3Ti4O12 sol-gel synthesized nanoparticle capacitors

    Science.gov (United States)

    Puli, Venkata Sreenivas; Adireddy, Shiva; Kothakonda, Manish; Elupula, Ravinder; Chrisey, Douglas B.

    This paper reports on synthesis of polycrystalline complex perovskite CaCu3Ti4O12 (as CCTO) ceramic powders prepared by a sol-gel auto combustion method at different sintering temperatures and sintering times, respectively. The effect of sintering time on the structure, morphology, dielectric and electrical properties of CCTO ceramics is investigated. Tuning the electrical properties via different sintering times is demonstrated for ceramic samples. X-ray diffraction (XRD) studies confirm perovskite-like structure at room temperature. Abnormal grain growth is observed for ceramic samples. Giant dielectric permittivity was realized for CCTO ceramics. High dielectric permittivity was attributed to the internal barrier layer capacitance (IBLC) model associated with the Maxwell-Wagner (MW) polarization mechanism.

  14. Permittivity and modulus spectroscopic study of BaFe0.5Nb0.5O3 ceramics

    Directory of Open Access Journals (Sweden)

    Subrat K. Kar

    2013-12-01

    Full Text Available Ba(Fe0.5Nb0.5O3 (BFN powder was synthesized in single perovskite phase by conventional solid state reaction route and BFN ceramic was obtained by uniaxial pressing and sintering at 1350 °C. Complex immittance like: permittivity and modulus spectroscopic formalism were simultaneously used to explain dielectric behaviour of the ceramics. The activation energy calculated from dielectric relaxation below 100 °C was found to be ~0.19 eV. The activation energy obtained from modulus spectra above 100 °C was ~0.59 eV. The space charge polarization model was used to explain the origin of relaxation and “giant” permittivity of BFN ceramics near room temperature.

  15. Integrating Argument-Based Science Inquiry with Modal Representations: Impact on Science Achievement, Argumentation, and Writing Skills

    Science.gov (United States)

    Demirbag, Mehmet; Gunel, Murat

    2014-01-01

    This study aims to investigate the effect of integrating the Argument-Based Science Inquiry (ABSI) approach with multi-modal representations on students' achievement, and their argumentation and writing skills. The study was conducted with 62 female and 57 male college students at the Central Anatolian Turkish University. All participants…

  16. Argumentation and Indigenous Knowledge: Socio-Historical Influences in Contextualizing an Argumentation Model in South African Schools

    Science.gov (United States)

    Gallard Martinez, Alejandro J.

    2011-01-01

    This forum considers argumentation as a means of science teaching in South African schools, through the integration of indigenous knowledge (IK). It addresses issues raised in Mariana G. Hewson and Meshach B. Ogunniyi's paper entitled: Argumentation-teaching as a method to introduce indigenous knowledge into science classrooms: opportunities and…

  17. Supporting Use of Evidence in Argumentation through Practice in Argumentation and Reflection in the Context of SOCRATES Learning Environment

    Science.gov (United States)

    Iordanou, Kalypso; Constantinou, Costas P.

    2015-01-01

    The aim of this study was to examine how students used evidence in argumentation while they engaged in argumentive and reflective activities in the context of a designed learning environment. A Web-based learning environment, SOCRATES, was developed, which included a rich data base on the topic of climate change. Sixteen 11th graders, working with…

  18. From gulf to bridge: when do moral arguments facilitate political influence?

    Science.gov (United States)

    Feinberg, Matthew; Willer, Robb

    2015-12-01

    Much of contemporary American political rhetoric is characterized by liberals and conservatives advancing arguments for the morality of their respective political positions. However, research suggests such moral rhetoric is largely ineffective for persuading those who do not already hold one's position because advocates advancing these arguments fail to account for the divergent moral commitments that undergird America's political divisions. Building on this, we hypothesize that (a) political advocates spontaneously make arguments grounded in their own moral values, not the values of those targeted for persuasion, and (b) political arguments reframed to appeal to the moral values of those holding the opposing political position are typically more effective. We find support for these claims across six studies involving diverse political issues, including same-sex marriage, universal health care, military spending, and adopting English as the nation's official langauge. Mediation and moderation analyses further indicated that reframed moral appeals were persuasive because they increased the apparent agreement between the political position and the targeted individuals' moral values.

  19. Effective conductivity and permittivity of unsaturated porous materials in the frequency range 1 mHz-1GHz.

    Science.gov (United States)

    Revil, A

    2013-01-01

    A model combining low-frequency complex conductivity and high-frequency permittivity is developed in the frequency range from 1 mHz to 1 GHz. The low-frequency conductivity depends on pore water and surface conductivities. Surface conductivity is controlled by the electrical diffuse layer, the outer component of the electrical double layer coating the surface of the minerals. The frequency dependence of the effective quadrature conductivity shows three domains. Below a critical frequency fp , which depends on the dynamic pore throat size Λ, the quadrature conductivity is frequency dependent. Between fp and a second critical frequency fd , the quadrature conductivity is generally well described by a plateau when clay minerals are present in the material. Clay-free porous materials with a narrow grain size distribution are described by a Cole-Cole model. The characteristic frequency fd controls the transition between double layer polarization and the effect of the high-frequency permittivity of the material. The Maxwell-Wagner polarization is found to be relatively negligible. For a broad range of frequencies below 1 MHz, the effective permittivity exhibits a strong dependence with the cation exchange capacity and the specific surface area. At high frequency, above the critical frequency fd , the effective permittivity reaches a high-frequency asymptotic limit that is controlled by the two Archie's exponents m and n like the low-frequency electrical conductivity. The unified model is compared with various data sets from the literature and is able to explain fairly well a broad number of observations with a very small number of textural and electrochemical parameters. It could be therefore used to interpret induced polarization, induction-based electromagnetic methods, and ground penetrating radar data to characterize the vadose zone.

  20. Modeling the Permittivity of Two-Phase Media Containing Monodisperse Spheres: Effects of Microstructure and Multiple Scattering

    OpenAIRE

    Doyle, Timothy E; Robinson, David A.; Scott B. Jones; Warnick, Keith H.; Carruth, Brent L.

    2007-01-01

    A numerical modeling approach was developed to predict the dielectric properties of heterogeneous particulate materials with arbitrary microstructures. To test the method, simulation and experimental data were acquired for the effective permittivities of various glass sphere suspensions. Both ordered lattices and random microstructures of up to 3600 spheres were modeled for volume fractions of 0.025–0.60. The electric fields in the suspensions were computed using an iterative multipole method...

  1. Nano-laminate vs. direct deposition of high permittivity gadolinium scandate on silicon by high pressure sputtering

    Energy Technology Data Exchange (ETDEWEB)

    Feijoo, P.C., E-mail: pedronska@fis.ucm.es [Dpto. Física Aplicada III (Electricidad y Electrónica), Universidad Complutense de Madrid, Fac. de CC. Físicas. Av/Complutense S/N, E-28040 Madrid (Spain); Pampillón, M.A.; San Andrés, E. [Dpto. Física Aplicada III (Electricidad y Electrónica), Universidad Complutense de Madrid, Fac. de CC. Físicas. Av/Complutense S/N, E-28040 Madrid (Spain); Fierro, J.L.G. [Instituto de Catálisis y Petroleoquímica, Consejo Superior de Investigaciones Científicas, C/Marie Curie 2, E-28049 Cantoblanco (Spain)

    2015-10-30

    In this work we use the high pressure sputtering technique to deposit the high permittivity dielectric gadolinium scandate on silicon substrates. This nonconventional deposition technique prevents substrate damage and allows for growth of ternary compounds with controlled composition. Two different approaches were assessed: the first one consists of depositing the material directly from a stoichiometric GdScO{sub 3} target; in the second one, we anneal a nano-laminate of < 0.5 nm thick Gd{sub 2}O{sub 3} and Sc{sub 2}O{sub 3} films in order to control the composition of the scandate. Metal–insulator–semiconductor capacitors were fabricated with platinum gates for electrical characterization. Accordingly, we grew a Gd-rich Gd{sub 2−x}Sc{sub x}O{sub 3} film that, in spite of higher leakage currents, presents a better effective relative permittivity of 21 and lower density of defects. - Highlights: • GdScO is deposited on Si as a high permittivity dielectric by two procedures. • Films sputtered from GdScO{sub 3} target are Sc-rich and present thick interface SiO{sub x}. • Gd-rich GdScO is obtained from a nano-laminate sputtered from Sc{sub 2}O{sub 3} and Gd{sub 2}O{sub 3}. • Gd{sub 1.8}Sc{sub 0.2}O{sub 3} shows good effective permittivity and electrical properties.

  2. Argumentation, confrontation et violence verbale fulgurante Argumentative Processes, Confrontation and Acute Verbal Abuse

    Directory of Open Access Journals (Sweden)

    Claudine Moïse

    2012-04-01

    Full Text Available Si nous avons défini la violence verbale fulgurante comme une montée en tension caractérisée par des actes menaçants directs (provocation, menace, insultes… et la violence polémique comme un discours à visée argumentative mobilisant des procédés discursifs indirects (implicites, ironie…, on ne peut considérer ces deux types de discours comme hermétiques. À travers des scènes de violences verbales quotidiennes dans l’espace public et institutionnel (contrôles, convocations, verbalisations…, constituées pour un DVD pédagogique, il s’agit de montrer comment dans des interactions caractérisées par la violence fulgurante, certains procédés argumentatifs particuliers et que nous décrirons, sont utilisés, avec force efficacité, à des fins de déstabilisation et de prise de pouvoir sur l’autre. Our research has defined severe verbal abuse as built up tension characterized by directly threatening acts (such as provocation, threats, insults, and polemical violence as argumentative discourse which mobilizes indirect discursive devices, such as implicit discourse relations and irony. Yet, neither type of discourse can be considered to be impervious to mutual influence. Based on the content of an educational DVD featuring acted out scenes of daily verbal abuse taking place in public and institutional spaces (i.e., checks, summons, fines, we will show how specific argumentative devices, which we will describe, are very efficiently used within interactions that are characterised by severe abuse, with the aim of destabilizing and taking control over somebody.

  3. Child labour. Refuting the "nimble fingers" argument.

    Science.gov (United States)

    1996-01-01

    According to an International Labor Organization (ILO) study, approximately 130,000 children work in India's hand-knotted carpet industry. In one-loom enterprises, children comprise 14% of all weavers; in businesses with five or more looms, this rate increases to 33%. India's Factories Act, which applies costly health, safety, and labor regulations to larger firms, has led to a proliferation of cottage industries. The finding that children are more likely to work on low-quality rather than highest-quality carpets refutes the "nimble fingers" argument used by apologists of child labor. Although child and adult weavers have similar productivity, children earn less while apprentices than trained weavers and serve to depress wages throughout the industry. According to ILO estimates, replacing the 22% of the work force currently occupied by children with adults would cause wages to rise by about 5%. The overall savings in production costs from the use of child labor are very small when compared to the foreign retail price of the carpets, which is often four times the Indian export price. The ILO has urged an international approach to the elimination of child labor, in which all carpet-producing countries simultaneously implement a no-child-labor strategy to avoid placing any one country at a competitive disadvantage. Given the thousands of cottages where one or two carpets are woven per year, strategies such as labelling and regulation are likely to be ineffective. Solutions that address the general problems of poverty, while developing alternative sources of education and employment, are most likely to be effective in reducing child labor in countries such as India.

  4. Microwave permittivity of SiC-Al2O3 composite powder prepared by sol-gel and carbothermal reduction

    Institute of Scientific and Technical Information of China (English)

    LIU Xiao-kui; LUO Fa; ZHU Dong-mei; ZHOU Wan-cheng

    2006-01-01

    SiC-Al2O3 composite powder was prepared by sol-gel and carbothermal reduction method. The powder synthesized was characterized by X-ray diffraction(XRD) and scanning electron microscopy(SEM) to confirm the phase formation,and the thermodynamic analysis was performed systematically. Moreover,the variation of its microwave permittivity with different atomic ratio of Al/Si was investigated in the frequency range of 8.2-12.4 GHz. The results show that,the powder obtained consists of spherical particles of 300-400 nm in diameter,which are composed of SiC and Al2O3 microcrystal with the grain size of approximately 45 nm. The results of XRD accord with those of the thermodynamic analysis. It is impossible for Al atoms to dissolve in the lattice of SiC during the carbothermal reduction process. Along with the increase of atomic ratio of Al/Si in the xerogel,the amount of Al2O3 in the powder synthesized increases,which reduces both ε′,the real part of complex permittivity,and tgδ(ε″/ε′),the dissipation factor,where ε″ is the imaginary part of complex permittivity.

  5. A new approach for electrical properties estimation using a global integral equation and improvements using high permittivity materials

    Science.gov (United States)

    Schmidt, Rita; Webb, Andrew

    2016-01-01

    Electrical Properties Tomography (EPT) using MRI is a technique that has been developed to provide a new contrast mechanism for in vivo imaging. Currently the most common method relies on the solution of the homogeneous Helmholtz equation, which has limitations in accurate estimation at tissue interfaces. A new method proposed in this work combines a Maxwell's integral equation representation of the problem, and the use of high permittivity materials (HPM) to control the RF field, in order to reconstruct the electrical properties image. The magnetic field is represented by an integral equation considering each point as a contrast source. This equation can be solved in an inverse method. In this study we use a reference simulation or scout scan of a uniform phantom to provide an initial estimate for the inverse solution, which allows the estimation of the complex permittivity within a single iteration. Incorporating two setups with and without the HPM improves the reconstructed result, especially with respect to the very low electric field in the center of the sample. Electromagnetic simulations of the brain were performed at 3 T to generate the B1+ field maps and reconstruct the electric properties images. The standard deviations of the relative permittivity and conductivity were within 14% and 18%, respectively for a volume consisting of white matter, gray matter and cerebellum.

  6. Optical control of dielectric permittivity in LaAl0.99Zn0.01O3-δ

    Science.gov (United States)

    Nagai, Takayuki; Takahashi, Hidefumi; Okazaki, Ryuji; Tanabe, Kenji; Terasaki, Ichiro; Taniguchi, Hiroki

    2017-04-01

    A photo-dielectric effect (i.e., a change in dielectric permittivity due to photo-irradiation) has been demonstrated in LaAl0.99Zn0.01O3-δ. Photo-irradiation with an incident energy of 3.4 eV was found to enhance the dielectric permittivity in LaAl0.99Zn0.01O3-δ over a wide frequency range from 100 Hz to 1 MHz. The change in dielectric permittivity in the high-frequency region hardly depended on frequency and was not accompanied by an increase in dielectric loss, indicating an intrinsic photo-dielectric effect in LaAl0.99Zn0.01O3-δ that is not due to photo-conduction. The dependence of the photo-dielectric effect on incident energy suggests the existence of deep in-gap states introduced by Zn substitution. The mechanism of the photo-dielectric effect in LaAl0.99Zn0.01O3-δ relates to the dielectric response of the photo-excited electrons trapped in the deep in-gap states, which work as effective polar displacements under an applied electric field. These findings are expected to contribute to the development of photo-capacitors that enable the remote control of the dielectric response via photo-irradiation.

  7. A new approach for electrical properties estimation using a global integral equation and improvements using high permittivity materials.

    Science.gov (United States)

    Schmidt, Rita; Webb, Andrew

    2016-01-01

    Electrical Properties Tomography (EPT) using MRI is a technique that has been developed to provide a new contrast mechanism for in vivo imaging. Currently the most common method relies on the solution of the homogeneous Helmholtz equation, which has limitations in accurate estimation at tissue interfaces. A new method proposed in this work combines a Maxwell's integral equation representation of the problem, and the use of high permittivity materials (HPM) to control the RF field, in order to reconstruct the electrical properties image. The magnetic field is represented by an integral equation considering each point as a contrast source. This equation can be solved in an inverse method. In this study we use a reference simulation or scout scan of a uniform phantom to provide an initial estimate for the inverse solution, which allows the estimation of the complex permittivity within a single iteration. Incorporating two setups with and without the HPM improves the reconstructed result, especially with respect to the very low electric field in the center of the sample. Electromagnetic simulations of the brain were performed at 3T to generate the B1(+) field maps and reconstruct the electric properties images. The standard deviations of the relative permittivity and conductivity were within 14% and 18%, respectively for a volume consisting of white matter, gray matter and cerebellum.

  8. The Role of Concentration Dependent Static Permittivity of Electrolyte Solutions in the Debye-Hückel Theory.

    Science.gov (United States)

    Shilov, Ignat Yu; Lyashchenko, Andrey K

    2015-08-01

    The Debye-Hückel theory has been extended to allow for arbitrary concentration dependence of the electrolyte solution static permittivity. The theory follows the lines advanced by Erich Hückel ( Hückel, E. Phys. Z. 1925, 26, 93) but gives rise to more general and lucid results. New theoretical expressions have been obtained for the excess free energy of solution, activity coefficient of water and mean ionic activity coefficient. The thermodynamic functions contain two terms representing interionic interactions and ion-water (solvation) interactions. The theory has been applied to calculate the activity coefficients of components in the aqueous solutions of alkali metal chlorides from LiCl to CsCl at ambient conditions making use of permittivities taken from experimental dielectric relaxation studies. Calculations without parameter adjustment have demonstrated a semiquantitative agreement with experimental data, reproducing both the nonmonotonic concentration dependence of the activity coefficients and the ordering of activity coefficients for the salts with different cations. A good agreement with experimental data is obtained for the aqueous solutions of LiCl in the concentration range up to 10 mol/kg. The nonmonotonic concentration dependence of activity coefficients is explained as a result of a balance between the effect of interionic interactions and the solvation contribution which appears quite naturally in the framework of the Debye-Hückel approach after incorporation of variable permittivity of solution.

  9. The effect of very low water content on the complex dielectric permittivity of clays, sand-clay and sand rocks

    Science.gov (United States)

    Belyaeva, T. A.; Bobrov, P. P.; Kroshka, E. S.; Lapina, A. S.; Rodionova, O. V.

    2017-01-01

    The results of measurements of complex relative permittivity of bentonite and clayey sandstone with different degrees of salinity with low moisture are given in the range of temperatures -20° to  +105 °C at frequencies from 25 Hz to 1 GHz. It is shown, that even a small amount of water in sandy and sandy-argillaceous rocks causes an increase of the real part of complex relative permittivity at frequencies below 100 Hz. The explanation by linearly-broken dependence of refractive index on moisture is given at its small values. By a dielectric method it is shown that in the process of water film formation on the surface of a mineral, the water molecules binding energy changes. Big distinctions in low-frequency dielectric relaxation times testify to the change of binding energy of molecules of water on the surface of a mineral. Also dependences of relaxation times on temperature are various. The results of dielectric measurements showed a strong influence of the salt on the dielectric permittivity of the clay and clayey sandstone even at a low moisture level.

  10. Life and space dimensionality: A brief review of old and new entangled arguments

    CERN Document Server

    Caruso, Francisco

    2016-01-01

    A general sketch on how the problem of space dimensionality depends on anthropic arguments is presented. Several examples of how life has been used to constraint space dimensionality (and vice-versa) are reviewed. In particular, the influences of three-dimensionality in the solar system stability and the origin of life on Earth are discussed. New constraints on space dimensionality and on its invariance in very large spatial and temporal scales are also stressed.

  11. Structure and pragmatics in informal argument: circularity and question-begging.

    Science.gov (United States)

    Brem, Sarah K.

    2003-04-01

    Most everyday arguments are informal, as contrasted with the formal arguments of logic and mathematics. Whereas formal argument is well understood, the nature of informal argument is more elusive. A recent study by Rips (2002) provides further evidence regarding the roles of structure and pragmatics in informal argument.

  12. Using instruments to understand argument structure: Evidence for gradient representation.

    Science.gov (United States)

    Rissman, Lilia; Rawlins, Kyle; Landau, Barbara

    2015-09-01

    The arguments of a verb are commonly assumed to correspond to the event participants specified by the verb. That is, drink has two arguments because drink specifies two participants: someone who drinks and something that gets drunk. This correspondence does not appear to hold, however, in the case of instrumental participants, e.g. John drank the soda with a straw. Verbs such as slice and write have been argued to specify an instrumental participant, even though instruments do not pattern like arguments given other criteria. In this paper, we investigated how instrumental verbs are represented, testing the hypothesis that verbs such as slice encode three participants in the same way that dative verbs such as lend encode three participants. In two experiments English-speakers reported their judgments about the number of participants specified by a verb, e.g., that drink specifies two participants. These judgments indicate that slice does not encode three distinct arguments. Nonetheless, some verbs were systematically more likely to elicit the judgment that the instrument is specified by the verb, a pattern that held across individual subjects. To account for these findings, we propose that instruments are not independent verbal arguments but are represented in a gradient away: an instrument may be a more or less salient part of the force exerted by an agent. These results inform our understanding of the relationship between argument structure and event representation, raising questions concerning the role of arguments in language processing and learning.

  13. Moral Philosophy, Moral Expertise, and the Argument from Disagreement.

    Science.gov (United States)

    Cross, Ben

    2016-03-01

    Several recent articles have weighed in on the question of whether moral philosophers can be counted as moral experts. One argument denying this has been rejected by both sides of the debate. According to this argument, the extent of disagreement in modern moral philosophy prevents moral philosophers from being classified as moral experts. Call this the Argument From Disagreement (AD). In this article, I defend a version of AD. Insofar as practical issues in moral philosophy are characterized by disagreement between moral philosophers who are more or less equally well credentialed on the issue, non-philosophers have no good reasons to defer to their views. © 2015 John Wiley & Sons Ltd.

  14. Value-impregnated factual claims and slippery-slope arguments.

    Science.gov (United States)

    Helgesson, Gert; Lynøe, Niels; Juth, Niklas

    2017-03-01

    Slippery-slope arguments typically question a course of action by estimating that it will end in misery once the first unfortunate step is taken. Previous studies indicate that estimations of the long-term consequences of certain debated actions, such as legalizing physician-assisted suicide, may be strongly influenced by tacit personal values. In this paper, we suggest that to the extent that slippery-slope arguments rest on estimations of future events, they may be mere rationalizations of personal values. This might explain why there are proponents even for strikingly poor slippery-slope arguments.

  15. Computing Preferred Extensions for Argumentation Systems with Sets of Attacking

    DEFF Research Database (Denmark)

    Nielsen, Søren Holbech; Parsons, Simon

    2006-01-01

    The hitherto most abstract, and hence general, argumentation system, is the one described by Dung in a paper from 1995. This framework does not allow for joint attacks on arguments, but in a recent paper we adapted it to support such attacks, and proved that this adapted framework enjoyed the same...... formal properties as that of Dung. One problem posed by Dung's original framework, which was neglected for some time, is how to compute preferred extensions of the argumentation systems. However, in 2001, in a paper by Doutre and Mengin, a procedure was given for enumerating preferred extensions...

  16. Operating with External Arguments of Douady and Hubbard

    Directory of Open Access Journals (Sweden)

    G. Pastor

    2007-01-01

    Full Text Available The external arguments of the external rays theory of Douady and Hubbard is a valuable tool in order to analyze the Mandelbrot set, a typical case of discrete dynamical system used to study nonlinear phenomena. We suggest here a general method for the calculation of the external arguments of external rays landing at the hyperbolic components root points of the Mandelbrot set. Likewise, we present a general method for the calculation of the external arguments of external rays landing at Misiurewicz points.

  17. Argumentation Key to Communicating Climate Change to the Public

    Science.gov (United States)

    Bleicher, R. E.; Lambert, J. L.

    2012-12-01

    Argumentation plays an important role in how we communicate climate change science to the public and is a key component integrated throughout the Next Generation Science Standards. A scientific argument can be described as a disagreement between explanations with data being used to justify each position. Argumentation is social process where two or more individuals construct and critique arguments (Kuhn & Udell, 2003; Nussbaum, 1997). Sampson, Grooms, and Walker's (2011) developed a framework for understanding the components of a scientific argument. The three components start with a claim (a conjecture, conclusion, explanation, or an answer to a research question). This claim must fit the evidence (observations that show trends over time, relationships between variables or difference between groups). The evidence must be justified with reasoning (explains how the evidence supports the explanation and whey it should count as support). In a scientific argument, or debate, the controversy focuses on how data were collected, what data can or should be included, and what inferences can be made based on a set of evidence. Toulmin's model (1969) also includes rebutting or presenting an alternative explanation supported by counter evidence and reasoning of why the alternative is not the appropriate explanation for the question of the problem. The process of scientific argumentation should involve the construction and critique of scientific arguments, one that involves the consideration of alternative hypotheses (Lawson, 2003). Scientific literacy depends as much on the ability to refute and recognize poor scientific arguments as much as it does on the ability to present an effective argument based on good scientific data (Osborne, 2010). Argument is, therefore, a core feature of science. When students learn to construct a sound scientific argument, they demonstrate critical thinking and a mastery of the science being taught. To present a convincing argument in support of

  18. The influence of event-related knowledge on verb-argument processing in aphasia.

    Science.gov (United States)

    Dickey, Michael Walsh; Warren, Tessa

    2015-01-01

    Event-related conceptual knowledge outside the language system rapidly affects verb-argument processing in unimpaired adults (McRae and Matsuki, 2009). Some have argued that verb-argument processing is in fact reducible to the activation of such event-related knowledge. However, data favoring this conclusion have come primarily from college-aged healthy adults, for whom both linguistic and conceptual semantic processing is fast and automatic. This study examined the influence of event-related knowledge on verb-argument processing among adults with aphasia (n = 8) and older unimpaired controls (n = 60), in two self-paced reading studies. Participants read sentences containing a plausible verb-argument combination (Mary used a knife to chop the large carrots before dinner), a combination that violated event-related world knowledge (Mary used some bleach to clean the large carrots before dinner), or a combination that violated the verb's selectional restrictions (Mary used a pump to inflate the large carrots before dinner). The participants with aphasia naturally split into two groups: Group 1 (n = 4) had conceptual-semantic impairments (evidenced by poor performance on tasks like Pyramids & Palm Trees) but reasonably intact language processing (higher Western Aphasia Battery Aphasia Quotients), while Group 2 (n = 4) had intact conceptual semantics but poorer language processing. Older unimpaired controls and aphasic Group 1 showed rapid on-line disruption for sentences with selectional-restriction violations (SRVs) and event-related knowledge violations, and also showed SRV-specific penalties in sentence-final acceptability judgments (Experiment 1) and comprehension questions (Experiment 2). In contrast, Group 2 showed very few reliable differences across conditions in either on-line or off-line measures. This difference between aphasic groups suggests that verb-related information and event-related knowledge may be dissociated in aphasia. Furthermore, it suggests

  19. Predicate Argument Structure Analysis for Use Case Description Modeling

    Science.gov (United States)

    Takeuchi, Hironori; Nakamura, Taiga; Yamaguchi, Takahira

    In a large software system development project, many documents are prepared and updated frequently. In such a situation, support is needed for looking through these documents easily to identify inconsistencies and to maintain traceability. In this research, we focus on the requirements documents such as use cases and consider how to create models from the use case descriptions in unformatted text. In the model construction, we propose a few semantic constraints based on the features of the use cases and use them for a predicate argument structure analysis to assign semantic labels to actors and actions. With this approach, we show that we can assign semantic labels without enhancing any existing general lexical resources such as case frame dictionaries and design a less language-dependent model construction architecture. By using the constructed model, we consider a system for quality analysis of the use cases and automated test case generation to keep the traceability between document sets. We evaluated the reuse of the existing use cases and generated test case steps automatically with the proposed prototype system from real-world use cases in the development of a system using a packaged application. Based on the evaluation, we show how to construct models with high precision from English and Japanese use case data. Also, we could generate good test cases for about 90% of the real use cases through the manual improvement of the descriptions based on the feedback from the quality analysis system.

  20. The Connection and Distinction between the Design Argument with the Teleological Argument and the Best Creational System

    Directory of Open Access Journals (Sweden)

    Farah Ramin

    2011-09-01

    Full Text Available The design argument faced with big different writings in its Western background so that these writings have essential difference with each others. The design argument is posteriori demonstration for the existence of God which by analogy or induction and partial or general instances of the order in nature tries to affirm the intelligent designer.  Since the concepts of design and end have firm connection with each other in the Western writings of this design but the concepts of purposiveness of divine acts, purposiveness of nature and its best system is assumed the same with each other and obvious confusion has been made between the design argument with the teleological argument and the best creational system. The aim of the article is to consider order in the world based upon the united components of a system (design argument, final cause (teleological argument and best system (best creational system argument and also to manifest the connection and distinction of these three reasoning.