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Sample records for voltage category linivo4

  1. Categories of categories

    CERN Document Server

    Pisani, Claudio

    2007-01-01

    A certain amount of category theory is developed in an arbitrary finitely complete category with a factorization system on it, playing the role of the comprehensive factorization system on Cat. Those aspects related to the concepts of finality (in particular terminal objects), discreteness and components, representability, colimits and universal arrows, seem to be best expressed in this very general setting. Furthermore, at this level we are in fact doing not only (E,M)-category theory but, in a sense, also (E,M)-topology. Other axioms, regarding power objects, duality, exponentials and the arrow object, are considered.

  2. Adhesive Categories

    DEFF Research Database (Denmark)

    Lack, Stephen; Sobocinski, Pawel

    2003-01-01

    We introduce adhesive categories, which are categories with structure ensuring that pushouts along monomorphisms are well-behaved. Many types of graphical structures used in computer science are shown to be examples of adhesive categories. Double-pushout graph rewriting generalises well...... to rewriting on arbitrary adhesive categories....

  3. Adhesive Categories

    DEFF Research Database (Denmark)

    Lack, Stephen; Sobocinski, Pawel

    2004-01-01

    We introduce adhesive categories, which are categories with structure ensuring that pushouts along monomorphisms are well-behaved. Many types of graphical structures used in computer science are shown to be examples of adhesive categories. Double-pushout graph rewriting generalises well to rewrit...

  4. Contested Categories

    DEFF Research Database (Denmark)

    Drawing on social science perspectives, Contested Categories presents a series of empirical studies that engage with the often shifting and day-to-day realities of life sciences categories. In doing so, it shows how such categories remain contested and dynamic, and that the boundaries they create...... to life science categories. With contributions from an international team of scholars, this book will be essential reading for anyone interested in the social, legal, policy and ethical implications of science and technology and the life sciences....

  5. Tensor categories

    CERN Document Server

    Etingof, Pavel; Nikshych, Dmitri; Ostrik, Victor

    2015-01-01

    Is there a vector space whose dimension is the golden ratio? Of course not-the golden ratio is not an integer! But this can happen for generalizations of vector spaces-objects of a tensor category. The theory of tensor categories is a relatively new field of mathematics that generalizes the theory of group representations. It has deep connections with many other fields, including representation theory, Hopf algebras, operator algebras, low-dimensional topology (in particular, knot theory), homotopy theory, quantum mechanics and field theory, quantum computation, theory of motives, etc. This bo

  6. Symplectic Categories

    CERN Document Server

    Weinstein, Alan

    2009-01-01

    Quantization problems suggest that the category of symplectic manifolds and symplectomorphisms be augmented by the inclusion of canonical relations as morphisms. These relations compose well when a transversality condition is satisfied, but the failure of the most general compositions to be smooth manifolds means that the canonical relations do not comprise the morphisms of a category. We discuss several existing and potential remedies to the nontransversality problem. Some of these involve restriction to classes of lagrangian submanifolds for which the transversality property automatically holds. Others involve allowing lagrangian "objects" more general than submanifolds.

  7. Organizational Categories as Viewing Categories

    DEFF Research Database (Denmark)

    Mik-Meyer, Nanna

    This paper explores how two Danish rehabilitation organizations textual guidelines for assessment of clients' personality traits influence the actual evaluation of clients. The analysis will show how staff members produce institutional identities corresponding to organizational categories, which...... I elucidate how the two rehabilitation organizations local history, legislation, structural features of the present labour market and of social work result in a number of contradictions which make it difficult to deliver client-centred care. This exact goal is according to the staff one of the most...

  8. Feynman Categories

    CERN Document Server

    Kaufmann, Ralph M

    2013-01-01

    In this paper we give a new foundational categorical formulation for operations and relations and objects parameterizing them. This generalizes operads and all their cousins including but not limited to PROPs, modular operads, twisted (modular) operads as well as algebras over operads and an abundance of other related structures, such as FI--algebras. The usefulness of this approach is that it allows us to handle all the classical as well as more esoteric structures under a common framework and we can treat all the situations simultaneously. Many of the known constructions simply become Kan extensions. In this common framework, we also derive universal operations, such as those underlying Deligne's conjecture, construct Hopf algebras as well as perform resolutions, (co)bar transforms and Feynman transforms which are related to master equations. For these applications, we construct the relevant model category structures.

  9. Quotients of cluster categories

    OpenAIRE

    Jorgensen, Peter

    2007-01-01

    Higher cluster categories were recently introduced as a generalization of cluster categories. This paper shows that in Dynkin types A and D, half of all higher cluster categories are actually just quotients of cluster categories. The other half can be obtained as quotients of 2-cluster categories, the "lowest" type of higher cluster categories. Hence, in Dynkin types A and D, all higher cluster phenomena are implicit in cluster categories and 2-cluster categories. In contrast, the same is not...

  10. Enriched model categories and diagram categories

    CERN Document Server

    Guillou, Bertrand

    2011-01-01

    We collect in one place a variety of known and folklore results in enriched model category theory and add a few new twists. One twist is a new perspective on equivariant model categories. A central theme is a general procedure for constructing a Quillen adjunction, often a Quillen equivalence, between a given V-model category and a category of diagrams in V, where V is any good enriching category. From this perspective, we rederive the result of Schwede and Shipley that reasonable stable model categories are Quillen equivalent to diagram categories of spectra (alias categories of module spectra). The general theory will be applied to G-spectra in a sequel, and for that we need quite a few technical improvements and modifications of general model categorical results. We collect those here. They are bound to have applications in a variety of other contexts.

  11. Atomical Grothendieck categories

    Directory of Open Access Journals (Sweden)

    C. Năstăsescu

    2003-01-01

    Full Text Available Motivated by the study of Gabriel dimension of a Grothendieck category, we introduce the concept of atomical Grothendieck category, which has only two localizing subcategories, and we give a classification of this type of Grothendieck categories.

  12. Categories from scratch

    NARCIS (Netherlands)

    Poss, R.

    2014-01-01

    The concept of category from mathematics happens to be useful to computer programmers in many ways. Unfortunately, all "good" explanations of categories so far have been designed by mathematicians, or at least theoreticians with a strong background in mathematics, and this makes categories especiall

  13. Skew-closed categories

    CERN Document Server

    Street, Ross

    2012-01-01

    Spurred by the new examples found by Kornel Szlach\\'anyi of a form of lax monoidal category, the author felt the time ripe to publish a reworking of Eilenberg-Kelly's original paper on closed categories appropriate to the laxer context. The new examples are connected with bialgebroids. With Stephen Lack, we have also used the concept to give an alternative definition of quantum category and quantum groupoid. Szlach\\'anyi has called the lax notion {\\em skew monoidal}. This paper defines {\\em skew closed category}, proves Yoneda lemmas for categories enriched over such, and looks at closed cocompletion.

  14. Categories of Fractions Revisited

    OpenAIRE

    Fritz, Tobias

    2008-01-01

    The theory of categories of fractions as originally developed by Gabriel and Zisman is reviewed in a pedagogical manner giving detailed proofs of all statements. A weakening of the category of fractions axioms used by Higson is discussed and shown to be equivalent to the original axioms.

  15. Analysis of rare categories

    CERN Document Server

    He, Jingrui

    2012-01-01

    In many real-world problems, rare categories (minority classes) play essential roles despite their extreme scarcity. The discovery, characterization and prediction of rare categories of rare examples may protect us from fraudulent or malicious behavior, aid scientific discovery, and even save lives. This book focuses on rare category analysis, where the majority classes have smooth distributions, and the minority classes exhibit the compactness property. Furthermore, it focuses on the challenging cases where the support regions of the majority and minority classes overlap. The author has devel

  16. Representation of categories.

    Science.gov (United States)

    Boot, Inge; Pecher, Diane

    2011-01-01

    In the present study we investigated whether the mental representation of the concept categories is represented by the container image schema (Lakoff & Johnson, 1980). In two experiments participants decided whether two pictures were from the same category (animal or vehicle). Pictures were presented inside or outside a frame that should activate the container schema. We found that performance to pictures was influenced by the frame in congruence with the metaphorical mapping (same category—inside bounded region; different category—not in same bounded region). These results show that the concept categories is metaphorically represented by containers.

  17. Triangulated categories (AM-148)

    CERN Document Server

    Neeman, Amnon

    2014-01-01

    The first two chapters of this book offer a modern, self-contained exposition of the elementary theory of triangulated categories and their quotients. The simple, elegant presentation of these known results makes these chapters eminently suitable as a text for graduate students. The remainder of the book is devoted to new research, providing, among other material, some remarkable improvements on Brown''s classical representability theorem. In addition, the author introduces a class of triangulated categories""--the ""well generated triangulated categories""--and studies their properties. This

  18. Variation within categories.

    NARCIS (Netherlands)

    Das-Smaal, E.A.; Swart, de J.H.

    1984-01-01

    Two aspects of variation within categories, relating to different models of categorization, were investigated - frequency of dimensional values and typicality differences within values. The influence of range of typicality experienced during learning and of informational value of feedback was also

  19. Consumer Product Category Database

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Chemical and Product Categories database (CPCat) catalogs the use of over 40,000 chemicals and their presence in different consumer products. The chemical use...

  20. Categorial Minimalist Grammar

    CERN Document Server

    Amblard, Maxime; Retoré, Christian

    2010-01-01

    We first recall some basic notions on minimalist grammars and on categorial grammars. Next we shortly introduce partially commutative linear logic, and our representation of minimalist grammars within this categorial system, the so-called categorial minimalist grammars. Thereafter we briefly present \\lambda\\mu-DRT (Discourse Representation Theory) an extension of \\lambda-DRT (compositional DRT) in the framework of \\lambda\\mu calculus: it avoids type raising and derives different readings from a single semantic representation, in a setting which follows discourse structure. We run a complete example which illustrates the various structures and rules that are needed to derive a semantic representation from the categorial view of a transformational syntactic analysis.

  1. Analysis of rare categories

    CERN Document Server

    He, Jingrui

    2012-01-01

    This book focuses on rare category analysis where the majority classes have smooth distributions and the minority classes exhibit the compactness property. It focuses on challenging cases where the support regions of the majority and minority classes overlap.

  2. Abstract sectional category

    CERN Document Server

    Diaz, F; Garcia, P; Murillo, A; Remedios, J

    2011-01-01

    We study, in an abstract axiomatic setting, the notion of sectional category of a morphism. From this, we unify and generalize known results about this invariant in different settings as well as we deduce new applications.

  3. Tvorba konceptu category managementu

    OpenAIRE

    Lepař, Martin

    2012-01-01

    The goal of this thesis is to define proces of creating the concept of category management and to apply the proces via existing assortment concept of certain retail company. The theoretical part covers basics of category management, merchandising and other related disciplines and its influence to creating concepts. Practical part includes detailed description of creating the concept, realized by retail company, selling Do it yourself products. Creation proces will start by anylysing current s...

  4. A convenient differential category

    CERN Document Server

    Blute, Richard; Tasson, Christine

    2010-01-01

    In this paper, we show that the category of Mackey-complete, separated, topological convex bornological vector spaces and bornological linear maps is a differential category. Such spaces were introduced by Fr\\"olicher and Kriegl, where they were called convenient vector spaces. While much of the structure necessary to demonstrate this observation is already contained in Fr\\"olicher and Kriegl's book, we here give a new interpretation of the category of convenient vector spaces as a model of the differential linear logic of Ehrhard and Regnier. Rather than base our proof on the abstract categorical structure presented by Fr\\"olicher and Kriegl, we prefer to focus on the bornological structure of convenient vector spaces. We believe bornological structures will ultimately yield a wide variety of models of differential logics.

  5. Accurate Switched-Voltage voltage averaging circuit

    OpenAIRE

    金光, 一幸; 松本, 寛樹

    2006-01-01

    Abstract ###This paper proposes an accurate Switched-Voltage (SV) voltage averaging circuit. It is presented ###to compensated for NMOS missmatch error at MOS differential type voltage averaging circuit. ###The proposed circuit consists of a voltage averaging and a SV sample/hold (S/H) circuit. It can ###operate using nonoverlapping three phase clocks. Performance of this circuit is verified by PSpice ###simulations.

  6. Simplicial Descent Categories

    Science.gov (United States)

    Rodriguez Gonzalez, Beatriz

    2008-04-01

    Much of the homotopical and homological structure of the categories of chain complexes and topological spaces can be deduced from the existence and properties of the 'simple' functors Tot : {double chain complexes} -> {chain complexes} and geometric realization : {sSets} -> {Top}, or similarly, Tot : {simplicial chain complexes} -> {chain complexes} and | | : {sTop} -> {Top}. The purpose of this thesis is to abstract this situation, and to this end we introduce the notion of '(co)simplicial descent category'. It is inspired by Guillen-Navarros's '(cubical) descent categories'. The key ingredients in a (co)simplicial descent category D are a class E of morphisms in D, called equivalences, and a 'simple' functor s : {(co)simplicial objects in D} -> D. They must satisfy axioms like 'Eilenberg-Zilber', 'exactness' and 'acyclicity'. This notion covers a wide class of examples, as chain complexes, sSets, topological spaces, filtered cochain complexes (where E = filtered quasi-isomorphisms or E = E_2-isomorphisms), commutative differential graded algebras (with s = Navarro's Thom-Whitney simple), DG-modules over a DG-category and mixed Hodge complexes, where s = Deligne's simple. From the simplicial descent structure we obtain homotopical structure on D, as cone and cylinder objects. We use them to i) explicitly describe the morphisms of HoD=D[E^{-1}] similarly to the case of calculus of fractions; ii) endow HoD with a non-additive pre-triangulated structure, that becomes triangulated in the stable additive case. These results use the properties of a 'total functor', which associates to any biaugmented bisimplicial object a simplicial object. It is the simplicial analogue of the total chain complex of a double complex, and it is left adjoint to Illusie's 'decalage' functor.

  7. Highest weight categories and recollements

    OpenAIRE

    Krause, Henning

    2015-01-01

    We provide several equivalent descriptions of a highest weight category using recollements of abelian categories. Also, we explain the connection between sequences of standard and exceptional objects.

  8. Categories and Commutative Algebra

    CERN Document Server

    Salmon, P

    2011-01-01

    L. Badescu: Sur certaines singularites des varietes algebriques.- D.A. Buchsbaum: Homological and commutative algebra.- S. Greco: Anelli Henseliani.- C. Lair: Morphismes et structures algebriques.- B.A. Mitchell: Introduction to category theory and homological algebra.- R. Rivet: Anneaux de series formelles et anneaux henseliens.- P. Salmon: Applicazioni della K-teoria all'algebra commutativa.- M. Tierney: Axiomatic sheaf theory: some constructions and applications.- C.B. Winters: An elementary lecture on algebraic spaces.

  9. LIBERTARISMO & ERROR CATEGORIAL

    Directory of Open Access Journals (Sweden)

    Carlos G. Patarroyo G.

    2009-01-01

    Full Text Available En este artículo se ofrece una defensa del libertarismo frente a dos acusaciones según las cuales éste comete un error categorial. Para ello, se utiliza la filosofía de Gilbert Ryle como herramienta para explicar las razones que fundamentan estas acusaciones y para mostrar por qué, pese a que ciertas versiones del libertarismo que acuden a la causalidad de agentes o al dualismo cartesiano cometen estos errores, un libertarismo que busque en el indeterminismo fisicalista la base de la posibilidad de la libertad humana no necesariamente puede ser acusado de incurrir en ellos.

  10. Category Variability Effect in Category Learning with Auditory Stimuli

    Directory of Open Access Journals (Sweden)

    Lee-Xieng eYang

    2014-10-01

    Full Text Available The category variability effect refers to that people tend to classify the midpoint item between two categories as the category more variable. This effect is regarded as evidence against the exemplar model, such as GCM (Generalized Context Model and favoring the rule model, such as GRT (i.e., the decision bound model. Although this effect has been found in conceptual category learning, it is not often observed in perceptual category learning. To figure out why the category variability effect is seldom reported in the past studies, we propose two hypotheses. First, due to sequence effect, the midpoint item would be classified as different categories, when following different items. When we combine these inconsistent responses for the midpoint item, no category variability effect occurs. Second, instead of the combination of sequence effect in different categorization conditions, the combination of different categorization strategies conceals the category variability effect. One experiment is conducted with single tones of different frequencies as stimuli. The collected data reveal sequence effect. However, the modeling results with the MAC model and the decision bound model support that the existence of individual differences is the reason for why no category variability effect occurs. Three groups are identified by their categorization strategy. Group 1 is rule user, placing the category boundary close to the low-variability category, hence inducing category variability effect. Group 2 takes the MAC strategy and classifies the midpoint item as different categories, depending on its preceding item. Group 3 classifies the midpoint item as the low-variability category, which is consistent with the prediction of the decision bound model as well as GCM. Nonetheless, our conclusion is that category variability effect can be found in perceptual category learning, but might be concealed by the averaged data.

  11. From recollement of triangulated categories to recollement of abelian categories

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    In this paper,we prove that if a triangulated category D admits a recollement relative to triangulated categories D’ and D″,then the abelian category D/T admits a recollement relative to abelian categories D’/i(T) and D″/j(T) where T is a cluster tilting subcategory of D and satisfies i i (T)  T,j j (T) T.

  12. Characterisation of the VELO High Voltage System

    CERN Document Server

    Rakotomiaramanana, B; Eklund, L

    2008-01-01

    The high voltage system supplies the bias voltage to the 88 silicon sensors which comprise the LHCb Vertex Locator (VELO). This note describes the results of the tests which have been performed on the hardware of the high voltage system of the VELO. Each individual test detailed in this note corresponds to a specific requirement of the system. These requirements arise primarily from ensuring the safety of the silicon sensors and the quality of the data taken from the VELO modules. The tests performed are in four categories: normal operation of the high voltage system; vercation of its stability under operation; discussion of its behaviour in failure modes; and details of operation at low voltage. Noteworthy issues, identified through the tests, include the behaviour of the high voltage modules at voltages below 9V, the current limit that can be applied during ramping of the voltage, and the speed with which the voltage is cut during failures of the system. The results of these tests provide high confidence th...

  13. Characterisation of the VELO High Voltage System

    CERN Document Server

    Rakotomiaramanana, B; Parkes, C; Eklund, L

    2008-01-01

    The high voltage system supplies the bias voltage to the 88 silicon sensors which comprise the LHCb Vertex Locator (VELO). This note describes the results of the tests which have been performed on the hardware of the high voltage system of the VELO. Each individual test detailed in this note corresponds to a specific requirement of the system. These requirements arise primarily from ensuring the safety of the silicon sensors and the quality of the data taken from the VELO modules. The tests performed are in four categories: normal operation of the high voltage system; verification of its stability under operation; discussion of its behaviour in failure modes; and details of operation at low voltage. Noteworthy issues, identified through the tests, include the behaviour of the high voltage modules at voltages below 9V, the current limit that can be applied during ramping of the voltage, and the speed with which the voltage is cut during failures of the system. The results of these tests provide high confidence...

  14. Localization on Certain Grothendieck Categories

    Institute of Scientific and Technical Information of China (English)

    F.CASTANO-IGLESIAS; N.CHIFAN; C.NASTASESCU

    2009-01-01

    Using categorical techniques we obtain some results on localization and colocalization theory in Grothendieck categories with a set of small projective generators. In particular,we give a sufficient condition for such category to be semiartinian. For semiartinian Grothendieck categories where every simple object has a projective cover,we obtain that every localizing subcategory is a TTF-class. In addition,some applications to semiperfect categories are obtained.

  15. Chaos in Binary Category Computation

    CERN Document Server

    Gonçalves, Carlos Pedro

    2010-01-01

    Category computation theory deals with a web-based systemic processing that underlies the morphic webs, which constitute the basis of categorial logical calculus. It is proven that, for these structures, algorithmically incompressible binary patterns can be morphically compressed, with respect to the local connectivities, in a binary morphic program. From the local connectivites, there emerges a global morphic connection that can be characterized by a low length binary string, leading to the identification of chaotic categorial dynamics, underlying the algorithmically random pattern. The work focuses on infinite binary chains of C2, which is a category that implements an X-OR-based categorial logical calculus.

  16. Citation analysis of scientific categories.

    Science.gov (United States)

    Patience, Gregory S; Patience, Christian A; Blais, Bruno; Bertrand, Francois

    2017-05-01

    Databases catalogue the corpus of research literature into scientific categories and report classes of bibliometric data such as the number of citations to articles, the number of authors, journals, funding agencies, institutes, references, etc. The number of articles and citations in a category are gauges of productivity and scientific impact but a quantitative basis to compare researchers between categories is limited. Here, we compile a list of bibliometric indicators for 236 science categories and citation rates of the 500 most cited articles of each category. The number of citations per paper vary by several orders of magnitude and are highest in multidisciplinary sciences, general internal medicine, and biochemistry and lowest in literature, poetry, and dance. A regression model demonstrates that citation rates to the top articles in each category increase with the square root of the number of articles in a category and decrease proportionately with the age of the references: articles in categories that cite recent research are also cited more frequently. The citation rate correlates positively with the number of funding agencies that finance the research. The category h-index correlates with the average number of cites to the top 500 ranked articles of each category ([Formula: see text]). Furthermore, only a few journals publish the top 500 cited articles in each category: four journals publish 60% ([Formula: see text]) of these and ten publish 81% ([Formula: see text]).

  17. Transient Voltage Recorder

    Science.gov (United States)

    Medelius, Pedro J. (Inventor); Simpson, Howard J. (Inventor)

    2002-01-01

    A voltage transient recorder can detect lightning induced transient voltages. The recorder detects a lightning induced transient voltage and adjusts input amplifiers to accurately record transient voltage magnitudes. The recorder stores voltage data from numerous monitored channels, or devices. The data is time stamped and can be output in real time, or stored for later retrieval. The transient recorder, in one embodiment, includes an analog-to-digital converter and a voltage threshold detector. When an input voltage exceeds a pre-determined voltage threshold, the recorder stores the incoming voltage magnitude and time of arrival. The recorder also determines if its input amplifier circuits clip the incoming signal or if the incoming signal is too low. If the input data is clipped or too low, the recorder adjusts the gain of the amplifier circuits to accurately acquire subsequent components of the lightning induced transients.

  18. How do Category Managers Manage?

    DEFF Research Database (Denmark)

    Hald, Kim Sundtoft; Sigurbjornsson, Tomas

    2013-01-01

    The aim of this research is to explore the managerial role of category managers in purchasing. A network management perspective is adopted. A case based research methodology is applied, and three category managers managing a diverse set of component and service categories in a global production...... of the role of the category manager in purchasing....... firm is observed while providing accounts of their progress and results in meetings. We conclude that the network management classification scheme originally deve loped by Harland and Knight (2001) and Knight and Harland (2005) is a valuable and fertile theoretical framework for the analysis...

  19. DG categories and exceptional collections

    CERN Document Server

    Bodzenta-Skibińska, Agnieszka

    2012-01-01

    Bondal and Kapranov describe how to assign to a full exceptional collection on a variety X a DG category C such that the bounded derived category of coherent sheaves on X is equivalent to the bounded derived category of C. In this paper we show that the category C has finite dimensional spaces of morphisms. We describe how it behaves under mutations and present an algorithm allowing to calculate it for full exceptional collections with vanishing Ext^k groups for k > 1. Finally, we use it to describe an example of a non-commutative deformation of certain rational surfaces.

  20. Automatic voltage imbalance detector

    Science.gov (United States)

    Bobbett, Ronald E.; McCormick, J. Byron; Kerwin, William J.

    1984-01-01

    A device for indicating and preventing damage to voltage cells such as galvanic cells and fuel cells connected in series by detecting sequential voltages and comparing these voltages to adjacent voltage cells. The device is implemented by using operational amplifiers and switching circuitry is provided by transistors. The device can be utilized in battery powered electric vehicles to prevent galvanic cell damage and also in series connected fuel cells to prevent fuel cell damage.

  1. Mixed voltage VLSI design

    Science.gov (United States)

    Panwar, Ramesh; Rennels, David; Alkalaj, Leon

    1993-01-01

    A technique for minimizing the power dissipated in a Very Large Scale Integration (VLSI) chip by lowering the operating voltage without any significant penalty in the chip throughput even though low voltage operation results in slower circuits. Since the overall throughput of a VLSI chip depends on the speed of the critical path(s) in the chip, it may be possible to sustain the throughput rates attained at higher voltages by operating the circuits in the critical path(s) with a high voltage while operating the other circuits with a lower voltage to minimize the power dissipation. The interface between the gates which operate at different voltages is crucial for low power dissipation since the interface may possibly have high static current dissipation thus negating the gains of the low voltage operation. The design of a voltage level translator which does the interface between the low voltage and high voltage circuits without any significant static dissipation is presented. Then, the results of the mixed voltage design using a greedy algorithm on three chips for various operating voltages are presented.

  2. Categories with envelopes and imprints

    CERN Document Server

    Akbarov, Sergei

    2011-01-01

    An envelope in a category is a construction generalizing operations of "exterior completion", like completion of a locally convex space. Dually, an imprint generalizes operations of "interior enrichment", like saturation of a locally convex space. We give abstract definition for envelopes and imprints, prove existence of these objects in the categories of stereotype spaces and of stereotype algebras, and give some examples.

  3. Audiovisual recalibration of vowel categories

    NARCIS (Netherlands)

    Franken, M.K.M.; Eisner, F.; Schoffelen, J.M.; Acheson, D.J.; Hagoort, P.; McQueen, J.M.

    2017-01-01

    One of the most daunting tasks of a listener is to map a continuous auditory stream onto known speech sound categories and lexical items. A major issue with this mapping problem is the variability in the acoustic realizations of sound categories, both within and across speakers. Past research has

  4. Category O for quantum groups

    DEFF Research Database (Denmark)

    2015-01-01

    We study the BGG-categories O_q associated to quantum groups. We prove that many properties of the ordinary BGG-category O for a semisimple complex Lie algebra carry over to the quantum case. Of particular interest is the case when q is a complex root of unity. Here we prove a tensor decomposition...

  5. Dagger Categories of Tame Relations

    CERN Document Server

    Jacobs, Bart

    2011-01-01

    Within the context of an involutive monoidal category the notion of a comparison relation is identified. Instances are equality on sets, inequality on posets, orthogonality on orthomodular lattices, non-empty intersection on powersets, and inner product on vector or Hilbert spaces. Associated with a collection of such (symmetric) comparison relations a dagger category is defined with "tame" relations as morphisms. Examples include familiar categories in the foundations of quantum mechanics, such as sets with partial injections, or with locally bifinite relations, or with formal distributions between them, or Hilbert spaces with bounded (continuous) linear maps. Of one particular example of such a dagger category of tame relations, involving sets and bifinite multirelations between them, the categorical structure is investigated in some detail. It turns out to involve symmetric monoidal dagger structure, with biproducts, and dagger kernels. This category may form an appropriate universe for discrete quantum co...

  6. Abelian categories in dimension 2

    CERN Document Server

    Dupont, Mathieu

    2008-01-01

    The goal of this thesis is to define a 2-dimensional version of abelian categories, where symmetric 2-groups play the role that abelian groups played in 1-dimensional algebra. Abelian and 2-abelian groupoid enriched categories are defined and it is proved that homology can be developed in them, including the existence of a long exact sequence of homology corresponding to an extension of chain complexes. This generalises known results for symmetric 2-groups. The examples include, in addition to symmetric 2-groups, the 2-modules on a 2-ring, which form a 2-abelian groupoid enriched category. Moreover, internal groupoids, functors and natural transformations in an abelian category C (in particular, Baez-Crans 2-vector spaces) form a 2-abelian groupoid enriched category if and only if the axiom of choice holds in C.

  7. Functional categories in comparative linguistics

    DEFF Research Database (Denmark)

    Rijkhoff, Jan

    ’, meaning-based categories. The use of meaning-based or semantic categories, however, does not necessarily result in the identification of cross-linguistically comparable data either, as was already shown by Greenberg (1966: 88) himself. Whereas formal categories are too narrow in that they do not cover all...... the structural variants attested across languages, semantic categories can be too wide, including too many structural variants to be useful for e.g. morphosyntactic typology. Furthermore, major typological word order studies after Greenberg (1966) have failed to keep formal and semantic categories apart......: language diversity and its importance for cognitive science. Behavioral and Brain Sciences 32-5, 429–92. Greenberg, Joseph H. 1963. Some universals of grammar with particular reference to the order of meaningful elements. In Joseph H. Greenberg (ed.), Universals of Language, 73-113. Cambridge: MIT. Keesing...

  8. Functional categories in comparative linguistics

    DEFF Research Database (Denmark)

    Rijkhoff, Jan

    in the process of verbal communication (in the tradition of the Prague School). I will argue that (a) functional categorization is methodologically prior to formal and semantic categorization (functional categories include semantic and formal categories) and (b) functional categories give better cross...... in their attempt to account for cross-linguistic ordering tendencies (Rijkhoff 2009a).       Recent proposals to employ ‘concepts’ as the basis for cross-linguistic comparison (apparently conflating linguistic/semantic and non-linguistic/cognitive categories) have also met with considerable skepticism (Levinson......, Roger M. 1979. Linguistic knowledge and cultural knowledge: some doubts and speculation. American Anthropologist 81-1, 14-36. Levinson, Stephen C. 1997. From outer to inner space: linguistic categories and non-linguistic thinking. In J. Nuyts and E. Pederson (eds.), Language and Conceptualization, 13...

  9. How categories come to matter

    DEFF Research Database (Denmark)

    Cohn, Marisa

    2013-01-01

    In a study of users' interactions with Siri, the iPhone personal assistant application, we noticed the emergence of overlaps and blurrings between explanatory categories such as "human" and "machine". We found that users work to purify these categories, thus resolving the tensions related to the ...... initial data analysis, due to our own forms of latent purification, and outline the particular analytic techniques that helped lead to this discovery. We thus provide an illustrative case of how categories come to matter in HCI research and design....

  10. Causal categories: relativistically interacting processes

    CERN Document Server

    Coecke, Bob

    2011-01-01

    A symmetric monoidal category naturally arises as the mathematical structure that organizes physical systems, processes, and composition thereof, both sequentially and in parallel. This structure admits a purely graphical calculus. This paper is concerned with the encoding of a fixed causal structure within a symmetric monoidal category: causal dependencies will correspond to topological connectedness in the graphical language. We show that correlations, either classical or quantum, force terminality of the tensor unit. We also show that well-definedness of the concept of a global state forces the monoidal product to be only partially defined, which in turn results in a relativistic covariance theorem. Except for these assumptions, at no stage do we assume anything more than purely compositional symmetric-monoidal categorical structure. We cast these two structural results in terms of a mathematical entity, which we call a `causal category'. We provide methods of constructing causal categories, and we study t...

  11. Constraint-Based Categorial Grammar

    CERN Document Server

    Bouma, G; Bouma, Gosse; Noord, Gertjan van

    1994-01-01

    We propose a generalization of Categorial Grammar in which lexical categories are defined by means of recursive constraints. In particular, the introduction of relational constraints allows one to capture the effects of (recursive) lexical rules in a computationally attractive manner. We illustrate the linguistic merits of the new approach by showing how it accounts for the syntax of Dutch cross-serial dependencies and the position and scope of adjuncts in such constructions. Delayed evaluation is used to process grammars containing recursive constraints.

  12. Rigidification of quasi-categories

    CERN Document Server

    Dugger, Daniel

    2009-01-01

    We give a new construction for rigidifying a quasi-category into a simplicial category, and prove that it is weakly equivalent to the rigidification given by Lurie. Our construction comes from the use of necklaces, which are simplicial sets obtained by stringing simplices together. As an application of these methods, we use our model to reprove some basic facts from Lurie's "Higher Topos Theory" regarding the rigidification process.

  13. VKCDB: Voltage-gated potassium channel database

    Directory of Open Access Journals (Sweden)

    Gallin Warren J

    2004-01-01

    Full Text Available Abstract Background The family of voltage-gated potassium channels comprises a functionally diverse group of membrane proteins. They help maintain and regulate the potassium ion-based component of the membrane potential and are thus central to many critical physiological processes. VKCDB (Voltage-gated potassium [K] Channel DataBase is a database of structural and functional data on these channels. It is designed as a resource for research on the molecular basis of voltage-gated potassium channel function. Description Voltage-gated potassium channel sequences were identified by using BLASTP to search GENBANK and SWISSPROT. Annotations for all voltage-gated potassium channels were selectively parsed and integrated into VKCDB. Electrophysiological and pharmacological data for the channels were collected from published journal articles. Transmembrane domain predictions by TMHMM and PHD are included for each VKCDB entry. Multiple sequence alignments of conserved domains of channels of the four Kv families and the KCNQ family are also included. Currently VKCDB contains 346 channel entries. It can be browsed and searched using a set of functionally relevant categories. Protein sequences can also be searched using a local BLAST engine. Conclusions VKCDB is a resource for comparative studies of voltage-gated potassium channels. The methods used to construct VKCDB are general; they can be used to create specialized databases for other protein families. VKCDB is accessible at http://vkcdb.biology.ualberta.ca.

  14. Data categories for marine planning

    Science.gov (United States)

    Lightsom, Frances L.; Cicchetti, Giancarlo; Wahle, Charles M.

    2015-01-01

    The U.S. National Ocean Policy calls for a science- and ecosystem-based approach to comprehensive planning and management of human activities and their impacts on America’s oceans. The Ocean Community in Data.gov is an outcome of 2010–2011 work by an interagency working group charged with designing a national information management system to support ocean planning. Within the working group, a smaller team developed a list of the data categories specifically relevant to marine planning. This set of categories is an important consensus statement of the breadth of information types required for ocean planning from a national, multidisciplinary perspective. Although the categories were described in a working document in 2011, they have not yet been fully implemented explicitly in online services or geospatial metadata, in part because authoritative definitions were not created formally. This document describes the purpose of the data categories, provides definitions, and identifies relations among the categories and between the categories and external standards. It is intended to be used by ocean data providers, managers, and users in order to provide a transparent and consistent framework for organizing and describing complex information about marine ecosystems and their connections to humans.

  15. Technological Aspects: High Voltage

    CERN Document Server

    Faircloth, D C

    2013-01-01

    This paper covers the theory and technological aspects of high-voltage design for ion sources. Electric field strengths are critical to understanding high-voltage breakdown. The equations governing electric fields and the techniques to solve them are discussed. The fundamental physics of high-voltage breakdown and electrical discharges are outlined. Different types of electrical discharges are catalogued and their behaviour in environments ranging from air to vacuum are detailed. The importance of surfaces is discussed. The principles of designing electrodes and insulators are introduced. The use of high-voltage platforms and their relation to system design are discussed. The use of commercially available high-voltage technology such as connectors, feedthroughs and cables are considered. Different power supply technologies and their procurement are briefly outlined. High-voltage safety, electric shocks and system design rules are covered.

  16. Stray voltage mitigation

    Energy Technology Data Exchange (ETDEWEB)

    Jamali, B.; Piercy, R.; Dick, P. [Kinetrics Inc., Toronto, ON (Canada). Transmission and Distribution Technologies

    2008-04-09

    This report discussed issues related to farm stray voltage and evaluated mitigation strategies and costs for limiting voltage to farms. A 3-phase, 3-wire system with no neutral ground was used throughout North America before the 1930s. Transformers were connected phase to phase without any electrical connection between the primary and secondary sides of the transformers. Distribution voltage levels were then increased and multi-grounded neutral wires were added. The earth now forms a parallel return path for the neutral current that allows part of the neutral current to flow continuously through the earth. The arrangement is responsible for causing stray voltage. Stray voltage causes uneven milk production, increased incidences of mastitis, and can create a reluctance to drink water amongst cows when stray voltages are present. Off-farm sources of stray voltage include phase unbalances, undersized neutral wire, and high resistance splices on the neutral wire. Mitigation strategies for reducing stray voltage include phase balancing; conversion from single to 3-phase; increasing distribution voltage levels, and changing pole configurations. 22 refs., 5 tabs., 13 figs.

  17. High voltage engineering

    CERN Document Server

    Rizk, Farouk AM

    2014-01-01

    Inspired by a new revival of worldwide interest in extra-high-voltage (EHV) and ultra-high-voltage (UHV) transmission, High Voltage Engineering merges the latest research with the extensive experience of the best in the field to deliver a comprehensive treatment of electrical insulation systems for the next generation of utility engineers and electric power professionals. The book offers extensive coverage of the physical basis of high-voltage engineering, from insulation stress and strength to lightning attachment and protection and beyond. Presenting information critical to the design, selec

  18. High voltage test techniques

    CERN Document Server

    Kind, Dieter

    2001-01-01

    The second edition of High Voltage Test Techniques has been completely revised. The present revision takes into account the latest international developments in High Voltage and Measurement technology, making it an essential reference for engineers in the testing field.High Voltage Technology belongs to the traditional area of Electrical Engineering. However, this is not to say that the area has stood still. New insulating materials, computing methods and voltage levels repeatedly pose new problems or open up methods of solution; electromagnetic compatibility (EMC) or components and systems al

  19. Mitigation of Unbalanced Voltage Sags and Voltage Unbalance in CIGRE Low Voltage Distribution Network

    OpenAIRE

    Mustafa, Ghullam; Bak-Jensen, Birgitte; Mahat, Pukar; Cecati, Carlo

    2013-01-01

    Any problem with voltage in a power network is undesirable as it aggravates the quality of the power. Power electronic devices such as Voltage Source Converter (VSC) based Static Synchronous Compensator (STATCOM) etc. can be used to mitigate the voltage problems in the distribution system. The voltage problems dealt with in this paper are to show how to mitigate unbalanced voltage sags and voltage unbalance in the CIGRE Low Voltage (LV) test network and net-works like this. The voltage unbala...

  20. Voltage verification unit

    Science.gov (United States)

    Martin, Edward J.

    2008-01-15

    A voltage verification unit and method for determining the absence of potentially dangerous potentials within a power supply enclosure without Mode 2 work is disclosed. With this device and method, a qualified worker, following a relatively simple protocol that involves a function test (hot, cold, hot) of the voltage verification unit before Lock Out/Tag Out and, and once the Lock Out/Tag Out is completed, testing or "trying" by simply reading a display on the voltage verification unit can be accomplished without exposure of the operator to the interior of the voltage supply enclosure. According to a preferred embodiment, the voltage verification unit includes test leads to allow diagnostics with other meters, without the necessity of accessing potentially dangerous bus bars or the like.

  1. FINANCIAL CONTROL AS A CATEGORY

    Directory of Open Access Journals (Sweden)

    Andrey Yu. Volkov

    2014-01-01

    Full Text Available The article reveals the basics of “financial control” as a category. The main attention is concentrated on the “control” itself (asa term, multiplicity of interpretation of“financial control” term and its juristic-practical matching. The duality of financial control category is detected. The identity of terms “financial control” and “state financial control” is justified. The article also offers ways of development of financial control juristical regulation.

  2. A Morphism Double Category and Monoidal Structure

    Directory of Open Access Journals (Sweden)

    Saikat Chatterjee

    2013-01-01

    Full Text Available We provide a recipe for “fattening” a category that leads to the construction of a double category. Motivated by an example where the underlying category has vector spaces as objects, we show how a monoidal category leads to a law of composition, satisfying certain coherence properties, on the object set of the fattened category.

  3. On the Category of Partial Bijections

    Directory of Open Access Journals (Sweden)

    Emil Schwab

    2008-01-01

    Full Text Available Categories of partial functions have become increasingly important principally because of their applications in theoretical computer science. In this note we prove that the category of partial bijections between sets as an inverse-Baer*-category with closed projections and in which the idempotents split is an exact category. Finally the Noether isomorphism theorems are given for this exact category.

  4. Identification of Prelinguistic Phonological Categories

    Science.gov (United States)

    Ramsdell, Heather L.; Oller, D. Kimbrough; Buder, Eugene H.; Ethington, Corinna A.; Chorna, Lesya

    2014-01-01

    Purpose The prelinguistic infant’s babbling repertoire of syllables—the phonological categories that form the basis for early word learning—is noticed by caregivers who interact with infants around them. Prior research on babbling has not explored the caregiver’s role in recognition of early vocal categories as foundations for word learning. In the present work, the authors begin to address this gap. Method The authors explored vocalizations produced by 8 infants at 3 ages (8, 10, and 12 months) in studies illustrating identification of phonological categories through caregiver report, laboratory procedures simulating the caregiver’s natural mode of listening, and the more traditional laboratory approach (phonetic transcription). Results Caregivers reported small repertoires of syllables for their infants. Repertoires of similar size and phonetic content were discerned in the laboratory by judges who simulated the caregiver’s natural mode of listening. However, phonetic transcription with repeated listening to infant recordings yielded repertoire sizes that vastly exceeded those reported by caregivers and naturalistic listeners. Conclusions The results suggest that caregiver report and naturalistic listening by laboratory staff can provide a new way to explore key characteristics of early infant vocal categories, a way that may provide insight into later speech and language development. PMID:22490623

  5. Causal Categories: Relativistically Interacting Processes

    Science.gov (United States)

    Coecke, Bob; Lal, Raymond

    2013-04-01

    A symmetric monoidal category naturally arises as the mathematical structure that organizes physical systems, processes, and composition thereof, both sequentially and in parallel. This structure admits a purely graphical calculus. This paper is concerned with the encoding of a fixed causal structure within a symmetric monoidal category: causal dependencies will correspond to topological connectedness in the graphical language. We show that correlations, either classical or quantum, force terminality of the tensor unit. We also show that well-definedness of the concept of a global state forces the monoidal product to be only partially defined, which in turn results in a relativistic covariance theorem. Except for these assumptions, at no stage do we assume anything more than purely compositional symmetric-monoidal categorical structure. We cast these two structural results in terms of a mathematical entity, which we call a causal category. We provide methods of constructing causal categories, and we study the consequences of these methods for the general framework of categorical quantum mechanics.

  6. Category Accessibility and Impression Formation

    Science.gov (United States)

    Higgins, E. Tory; And Others

    1977-01-01

    The present study examined the immediate and delayed effects of unobtrusive exposure to personality trait terms (e.g., "reckless,""persistent") on subjects' subsequent judgments and recollection of information about another person. The implications of individual and situational variation in the accessibility of different categories for judgments…

  7. Relative Mal'tsev categories

    OpenAIRE

    2014-01-01

    We define relative regular Mal’tsev categories and give an overview of conditions which are equivalent to the relative Mal’tsev axiom. These include conditions on relations as well as conditions on simplicial objects. We also give various examples and counterexamples.

  8. A category of its own?

    DEFF Research Database (Denmark)

    Elklit, Jørgen; Roberts, Nigel S.

    1996-01-01

    At first sight, the electoral systems in Denmark, Germany, South Africa and Sweden may seem different and attaempt to categorize them together odd. All four, however, belong to the same category, which Arend Lijphart calls 'proportional representation two-tier districting systems', and the effect...

  9. Mosquito and Blackfly Category Manual.

    Science.gov (United States)

    Bowman, James S.; And Others

    This manual provides information needed to meet the standards for pesticide applicator certification. Section one is concerned with the morphology, life cycle and breeding areas of mosquitoes and the diseases resulting from their presence. The second section covers similar categories in relation to the black fly population. Calculation methods and…

  10. International Conference on Category Theory

    CERN Document Server

    Pedicchio, Maria; Rosolini, Guiseppe

    1991-01-01

    With one exception, these papers are original and fully refereed research articles on various applications of Category Theory to Algebraic Topology, Logic and Computer Science. The exception is an outstanding and lengthy survey paper by Joyal/Street (80 pp) on a growing subject: it gives an account of classical Tannaka duality in such a way as to be accessible to the general mathematical reader, and to provide a key for entry to more recent developments and quantum groups. No expertise in either representation theory or category theory is assumed. Topics such as the Fourier cotransform, Tannaka duality for homogeneous spaces, braided tensor categories, Yang-Baxter operators, Knot invariants and quantum groups are introduced and studies. From the Contents: P.J. Freyd: Algebraically complete categories.- J.M.E. Hyland: First steps in synthetic domain theory.- G. Janelidze, W. Tholen: How algebraic is the change-of-base functor?.- A. Joyal, R. Street: An introduction to Tannaka duality and quantum groups.- A. Jo...

  11. Mosquito and Blackfly Category Manual.

    Science.gov (United States)

    Bowman, James S.; And Others

    This manual provides information needed to meet the standards for pesticide applicator certification. Section one is concerned with the morphology, life cycle and breeding areas of mosquitoes and the diseases resulting from their presence. The second section covers similar categories in relation to the black fly population. Calculation methods and…

  12. High Voltage Distribution

    Science.gov (United States)

    Norbeck, Edwin; Miller, Michael; Onel, Yasar

    2010-11-01

    For detector arrays that require 5 to 10 kV at a few microamps each for hundreds of detectors, using hundreds of HV power supplies is unreasonable. Bundles of hundreds of HV cables take up space that should be filled with detectors. A typical HV module can supply 1 ma, enough current for hundreds of detectors. It is better to use a single HV module and distribute the current as needed. We show a circuit that, for each detector, measures the current, cuts off the voltage if the current exceeds a set maximum, and allows the HV to be turned on or off from a control computer. The entire array requires a single HV cable and 2 or 3 control lines. This design provides the same voltage to all of the detectors, the voltage set by the single HV module. Some additional circuitry would allow a computer controlled voltage drop between the HV and each individual detector.

  13. High voltage engineering fundamentals

    CERN Document Server

    Kuffel, E; Hammond, P

    1984-01-01

    Provides a comprehensive treatment of high voltage engineering fundamentals at the introductory and intermediate levels. It covers: techniques used for generation and measurement of high direct, alternating and surge voltages for general application in industrial testing and selected special examples found in basic research; analytical and numerical calculation of electrostatic fields in simple practical insulation system; basic ionisation and decay processes in gases and breakdown mechanisms of gaseous, liquid and solid dielectrics; partial discharges and modern discharge detectors; and over

  14. Low-voltage gyrotrons

    Science.gov (United States)

    Glyavin, M. Yu.; Zavolskiy, N. A.; Sedov, A. S.; Nusinovich, G. S.

    2013-03-01

    For a long time, the gyrotrons were primarily developed for electron cyclotron heating and current drive of plasmas in controlled fusion reactors where a multi-megawatt, quasi-continuous millimeter-wave power is required. In addition to this important application, there are other applications (and their number increases with time) which do not require a very high power level, but such issues as the ability to operate at low voltages and have compact devices are very important. For example, gyrotrons are of interest for a dynamic nuclear polarization, which improves the sensitivity of the nuclear magnetic resonance spectroscopy. In this paper, some issues important for operation of gyrotrons driven by low-voltage electron beams are analyzed. An emphasis is made on the efficiency of low-voltage gyrotron operation at the fundamental and higher cyclotron harmonics. These efficiencies calculated with the account for ohmic losses were, first, determined in the framework of the generalized gyrotron theory based on the cold-cavity approximation. Then, more accurate, self-consistent calculations for the fundamental and second harmonic low-voltage sub-THz gyrotron designs were carried out. Results of these calculations are presented and discussed. It is shown that operation of the fundamental and second harmonic gyrotrons with noticeable efficiencies is possible even at voltages as low as 5-10 kV. Even the third harmonic gyrotrons can operate at voltages about 15 kV, albeit with rather low efficiency (1%-2% in the submillimeter wavelength region).

  15. Different Categories of Business Risk

    Directory of Open Access Journals (Sweden)

    Simona-Valeria TOMA

    2011-11-01

    Full Text Available Every business organisation involves some element of risk. Unmitigated risks can result in lost opportunity, financial losses, loss of reputation, or loss of the right to operate in a jurisdiction. Like any other risk type, understanding business risks is quite important for every business to garner profits instead of facing losses. A business risk is a universal risk type; this means that every business in the world faces business risks. Therefore, it is imperative to understand the different categories of business risk in order to create the appropriate strategies. The aim of this paper is to describe the most important categories of business risks and to make sure that every type of risk receives equal treatment and consideration.

  16. A Formal Calculus for Categories

    DEFF Research Database (Denmark)

    Cáccamo, Mario José

    This dissertation studies the logic underlying category theory. In particular we present a formal calculus for reasoning about universal properties. The aim is to systematise judgements about functoriality and naturality central to categorical reasoning. The calculus is based on a language which...... extends the typed lambda calculus with new binders to represent universal constructions. The types of the languages are interpreted as locally small categories and the expressions represent functors. The logic supports a syntactic treatment of universality and duality. Contravariance requires a definition...... of universality generous enough to deal with functors of mixed variance. Ends generalise limits to cover these kinds of functors and moreover provide the basis for a very convenient algebraic manipulation of expressions. The equational theory of the lambda calculus is extended with new rules for the definitions...

  17. Different Categories of Business Risk

    Directory of Open Access Journals (Sweden)

    Ioana-Veronica ALEXA

    2012-08-01

    Full Text Available Every business organisation involves some elements of risk. Unmitigated risks can result in lost opportunity, financial losses, loss of reputation, or loss of the right to operate in a jurisdiction. Like any other risk type, understanding business risks is quite important for every business to garner profits instead of facing losses. A business risk is a universal risk type; this means that every business in the world faces business risks. Therefore, it is imperative to understand the different categories of business risk in order creating the appropriate strategies. The aim of this paper is to describe the most important categories of business risks and to demonstrate that every type of risk has to receive equal treatment and consideration.

  18. Fusion categories and homotopy theory

    CERN Document Server

    Etingof, Pavel; Ostrik, Victor

    2009-01-01

    We apply the yoga of classical homotopy theory to classification problems of G-extensions of fusion and braided fusion categories, where G is a finite group. Namely, we reduce such problems to classification (up to homotopy) of maps from BG to classifiying spaces of certain higher groupoids. In particular, to every fusion category C we attach the 3-groupoid BrPic(C) of invertible C-bimodule categories, called the Brauer-Picard groupoid of C, such that equivalence classes of G-extensions of C are in bijection with homotopy classes of maps from BG to the classifying space of BrPic(C). This gives rise to an explicit description of both the obstructions to existence of extensions and the data parametrizing them; we work these out both topologically and algebraically. One of the central results of the paper is that the 2-truncation of BrPic(C) is canonically the 2-groupoid of braided autoequivalences of the Drinfeld center Z(C) of C. In particular, this implies that the Brauer-Picard group BrPic(C) (i.e., the grou...

  19. Equivalences between Categories of Modules and Categories of Comodules

    Institute of Scientific and Technical Information of China (English)

    Joost VERCRUYSSE

    2008-01-01

    We show the close connection between apparently different Galois theories for comodules introduced recently in [J.Gómez-Torrecillas and J.Vercruysse,Comatrix corings and Galois Comodules over firm rings,Algebr.Represent.Theory,10 (2007),271-306]and [Wisbauer,On Galois comodules, Comm.Algebra 34 (2006),2683-2711].Furthermore we study equivalences between categories of comodules over a coring and modules over a firm ring.We show that these equivalences are related to Galois theory for comodules.

  20. Device for monitoring cell voltage

    Science.gov (United States)

    Doepke, Matthias [Garbsen, DE; Eisermann, Henning [Edermissen, DE

    2012-08-21

    A device for monitoring a rechargeable battery having a number of electrically connected cells includes at least one current interruption switch for interrupting current flowing through at least one associated cell and a plurality of monitoring units for detecting cell voltage. Each monitoring unit is associated with a single cell and includes a reference voltage unit for producing a defined reference threshold voltage and a voltage comparison unit for comparing the reference threshold voltage with a partial cell voltage of the associated cell. The reference voltage unit is electrically supplied from the cell voltage of the associated cell. The voltage comparison unit is coupled to the at least one current interruption switch for interrupting the current of at least the current flowing through the associated cell, with a defined minimum difference between the reference threshold voltage and the partial cell voltage.

  1. High voltage pulse generator

    Science.gov (United States)

    Fasching, George E.

    1977-03-08

    An improved high-voltage pulse generator has been provided which is especially useful in ultrasonic testing of rock core samples. An N number of capacitors are charged in parallel to V volts and at the proper instance are coupled in series to produce a high-voltage pulse of N times V volts. Rapid switching of the capacitors from the paralleled charging configuration to the series discharging configuration is accomplished by using silicon-controlled rectifiers which are chain self-triggered following the initial triggering of a first one of the rectifiers connected between the first and second of the plurality of charging capacitors. A timing and triggering circuit is provided to properly synchronize triggering pulses to the first SCR at a time when the charging voltage is not being applied to the parallel-connected charging capacitors. Alternate circuits are provided for controlling the application of the charging voltage from a charging circuit to be applied to the parallel capacitors which provides a selection of at least two different intervals in which the charging voltage is turned "off" to allow the SCR's connecting the capacitors in series to turn "off" before recharging begins. The high-voltage pulse-generating circuit including the N capacitors and corresponding SCR's which connect the capacitors in series when triggered "on" further includes diodes and series-connected inductors between the parallel-connected charging capacitors which allow sufficiently fast charging of the capacitors for a high pulse repetition rate and yet allow considerable control of the decay time of the high-voltage pulses from the pulse-generating circuit.

  2. Highest Weight Categories For Number Rings

    CERN Document Server

    Pilkington, Annette

    2011-01-01

    This paper examines the concept of a stratified exact category in the context of number rings and corresponding Galois groups. BGG reciprocity and duality are proven for these categories making them highest weight categories. The strong connections between the structure of the category and ramification in the ring are explored.

  3. Mapping spaces in Quasi-categories

    CERN Document Server

    Dugger, Daniel

    2009-01-01

    We apply the Dwyer-Kan theory of homotopy function complexes in model categories to the study of mapping spaces in quasi-categories. Using this, together with our work on rigidification from [DS1], we give a streamlined proof of the Quillen equivalence between quasi-categories and simplicial categories. Some useful material about relative mapping spaces in quasi-categories is developed along the way.

  4. Voltage Regulators for Photovoltaic Systems

    Science.gov (United States)

    Delombard, R.

    1986-01-01

    Two simple circuits developed to provide voltage regulation for highvoltage (i.e., is greater than 75 volts) and low-voltage (i.e., is less than 36 volts) photovoltaic/battery power systems. Use of these circuits results in voltage regulator small, low-cost, and reliable, with very low power dissipation. Simple oscillator circuit controls photovoltaic-array current to regulate system voltage and control battery charging. Circuit senses battery (and system) voltage and adjusts array current to keep battery voltage from exceeding maximum voltage.

  5. Studying Voltage Transformer Ferroresonance

    Directory of Open Access Journals (Sweden)

    Hamid Radmanesh

    2012-09-01

    Full Text Available This study studies the effect of Circuit Breaker Shunt Resistance (CBSR, Metal Oxide Vaistor (MOV and Neutral earth Resistance (NR on the control of ferroresonance in the voltage transformer. It is expected that NR can controlled ferroresonance better than MOV and CBSR. Study has been done on a one phase voltage transformer rated 100 VA, 275 kV. The simulation results reveal that considering the CBSR and MOV exhibits a great mitigating effect on ferroresonance overvoltages, but these resistances cannot control these phenomena for all range of parameters. By applying NR to the system structure, ferroresonance has been controlled and its amplitude has been damped for all parameters values.

  6. VOLTAGE REGULATORS ASYNCHRONOUS GENERATORS

    Directory of Open Access Journals (Sweden)

    Grigorash O. V.

    2015-06-01

    Full Text Available A promising is currently the use of asynchronous generators with capacitive excitation as a source of electricity in stand-alone power systems. Drive asynchronous generators may exercise as a thermal engine and wind wheel wind power plant or turbines of small hydropower plants. The article discusses the structural and schematics of voltage stabilizers and frequency of asynchronous generators with improved operational and technical specifications. Technical novelty of design solutions of the magnetic system and stabilizers asynchronous generator of electricity parameters confirmed by the patents for the invention of the Russian Federation. The proposed technical solution voltage stabilizer asynchronous generators, can reduce the weight of the block capacitors excitation and reactive power compensation, as well as to simplify the control system power circuit which has less power electronic devices. For wind power plants it is an important issue not only to stabilize the voltage of the generator, but also the frequency of the current. Recommend functionality stabilizer schemes parameters of electric power made for direct frequency converters with artificial and natural switching power electronic devices. It is also proposed as part of stabilization systems use single-phase voltage, three-phase transformers with rotating magnetic field, reduce the level of electromagnetic interference generated by power electronic devices for switching, enhance the efficiency and reliability of the stabilizer.

  7. Geomagnetism and Induced Voltage

    Science.gov (United States)

    Abdul-Razzaq, W.; Biller, R. D.

    2010-01-01

    Introductory physics laboratories have seen an influx of "conceptual integrated science" over time in their classrooms with elements of other sciences such as chemistry, biology, Earth science, and astronomy. We describe a laboratory to introduce this development, as it attracts attention to the voltage induced in the human brain as it…

  8. High-voltage picoamperemeter

    Energy Technology Data Exchange (ETDEWEB)

    Bugl, Andrea; Ball, Markus; Boehmer, Michael; Doerheim, Sverre; Hoenle, Andreas; Konorov, Igor [Technische Universitaet Muenchen, Garching (Germany); Ketzer, Bernhard [Technische Universitaet Muenchen, Garching (Germany); Helmholtz-Institut fuer Strahlen- und Kernphysik, Bonn (Germany)

    2014-07-01

    Current measurements in the nano- and picoampere region on high voltage are an important tool to understand charge transfer processes in micropattern gas detectors like the Gas Electron Multiplier (GEM). They are currently used to e.g. optimize the field configuration in a multi-GEM stack to be used in the ALICE TPC after the upgrade of the experiment during the 2nd long shutdown of the LHC. Devices which allow measurements down to 1pA at high voltage up to 6 kV have been developed at TU Muenchen. They are based on analog current measurements via the voltage drop over a switchable shunt. A microcontroller collects 128 digital ADC values and calculates their mean and standard deviation. This information is sent with a wireless transmitting unit to a computer and stored in a root file. A nearly unlimited number of devices can be operated simultaneously and read out by a single receiver. The results can also be displayed on a LCD directly at the device. Battery operation and the wireless readout are important to protect the user from any contact to high voltage. The principle of the device is explained, and systematic studies of their properties are shown.

  9. Interior Operators and Topological Categories

    CERN Document Server

    Luna-Torres, Joaquin

    2010-01-01

    The introduction of the categorical notion of closure operators has unified various important notions and has led to interesting examples and applications in diverse areas of mathematics (see for example, Dikranjan and Tholen (\\cite{DT})). For a topological space it is well-known that the associated closure and interior operators provide equivalent descriptions of the topology, but this is not true in general. So, it makes sense to define and study the notion of interior operators $I$ in the context of a category $\\mathfrak C$ and a fixed class $\\mathcal M$ of monomorphisms in $\\mathfrak C$ closed under composition in such a way that $\\mathfrak C$ is finitely $\\mathcal M$-complete and the inverse images of morphisms have both left and right adjoint, which is the purpose of this paper.

  10. Virtue Ethics: The Misleading Category

    Directory of Open Access Journals (Sweden)

    Martha Nussbaum

    1998-12-01

    Full Text Available Virtue ethics is frequently considered to be a single category of ethical theory, and a rival to Kantianismand Utilitarianism. I argue that this approach is a mistake, because both Kantians and Utilitarians can, and do, have an interest in the virtues and the forrnation of character. But even if we focus on the group of ethical theorists who are most commonly called "virtue theorists" because they reject the guidance of both Kantianism and Utilitarianism, and derive inspiration from ancient Greek ethics, there is little unity to this group. Although there is a thin common ground that links all the group's members - a focus on the formation of character, on the nature of the passions, and on choice over the whole course of life - there are also crucial differences among them.

  11. The configuration category of a product

    OpenAIRE

    de Brito, Pedro Boavida; Weiss, Michael S.

    2017-01-01

    A construction related to the Boardman-Vogt tensor product of operads allows us to describe the configuration category of a product manifold $M\\times N$ in terms of the configuration categories of the factors $M$ and $N$.

  12. BGP reflection functors in root categories

    Institute of Scientific and Technical Information of China (English)

    XIAO Jie; ZHANG Guanglian; ZHU Bin

    2005-01-01

    We define the BGP-reflection functors in the derived categories and the root categories. By Ringel's Hall algebra approach, the BGP-reflection functor is applicable to obtain the classical Weyl group action on the Lie algebra.

  13. Category of Generalized Intuitionistic Fuzzy Sets

    Institute of Scientific and Technical Information of China (English)

    YANGWan-cai; LIXiao-shen

    2005-01-01

    In this paper, category GIFS of generalized intuitionistic fuzzy sets(GIF) is built up. Topoi properties of category GIFS axe studied. Firstly, it is proved that the category GIFS has all topoi properties except that it has no subobject classifiers, Secondly, it is proved that the category GIFS has middle object and consequently GIFS is a weak topos.Thirdly, by the use of theory of weak topos GIFS,the power object of an object in GIFS is studied.

  14. A convenient category for directed homotopy

    DEFF Research Database (Denmark)

    Fajstrup, Lisbeth; Rosický, J.

    We propose a convenient category for directed homotopy consisting of preordered topological spaces generated by cubes. Its main advantage is that, like the category of topological spaces generated by simplices suggested by J. H. Smith, it is locally presentable.......We propose a convenient category for directed homotopy consisting of preordered topological spaces generated by cubes. Its main advantage is that, like the category of topological spaces generated by simplices suggested by J. H. Smith, it is locally presentable....

  15. A convenient category for directed homotopy

    DEFF Research Database (Denmark)

    Fajstrup, Lisbeth; Rosický, J.

    2008-01-01

    We propose a convenient category for directed homotopy consisting of "directed" topological spaces generated by "directed" cubes. Its main advantage is that, like the category of topological spaces generated by simplices suggested by J. H. Smith, it is locally presentable.......We propose a convenient category for directed homotopy consisting of "directed" topological spaces generated by "directed" cubes. Its main advantage is that, like the category of topological spaces generated by simplices suggested by J. H. Smith, it is locally presentable....

  16. Incremental Bayesian Category Learning from Natural Language

    Science.gov (United States)

    Frermann, Lea; Lapata, Mirella

    2016-01-01

    Models of category learning have been extensively studied in cognitive science and primarily tested on perceptual abstractions or artificial stimuli. In this paper, we focus on categories acquired from natural language stimuli, that is, words (e.g., "chair" is a member of the furniture category). We present a Bayesian model that, unlike…

  17. Weakly exact categories and the snake lemma

    CERN Document Server

    Jafari, Amir

    2009-01-01

    We generalize the notion of an exact category and introduce weakly exact categories. A proof of the snake lemma in this general setting is given. Some applications are given to illustrate how one can do homological algebra in a weakly exact category.

  18. Individual differences in attention during category learning

    NARCIS (Netherlands)

    Lee, M.D.; Wetzels, R.

    2010-01-01

    A central idea in many successful models of category learning—including the Generalized Context Model (GCM)—is that people selectively attend to those dimensions of stimuli that are relevant for dividing them into categories. We use the GCM to re-examine some previously analyzed category learning

  19. Cascade category-aware visual search.

    Science.gov (United States)

    Zhang, Shiliang; Tian, Qi; Huang, Qingming; Gao, Wen; Rui, Yong

    2014-06-01

    Incorporating image classification into image retrieval system brings many attractive advantages. For instance, the search space can be narrowed down by rejecting images in irrelevant categories of the query. The retrieved images can be more consistent in semantics by indexing and returning images in the relevant categories together. However, due to their different goals on recognition accuracy and retrieval scalability, it is hard to efficiently incorporate most image classification works into large-scale image search. To study this problem, we propose cascade category-aware visual search, which utilizes weak category clue to achieve better retrieval accuracy, efficiency, and memory consumption. To capture the category and visual clues of an image, we first learn category-visual words, which are discriminative and repeatable local features labeled with categories. By identifying category-visual words in database images, we are able to discard noisy local features and extract image visual and category clues, which are hence recorded in a hierarchical index structure. Our retrieval system narrows down the search space by: 1) filtering the noisy local features in query; 2) rejecting irrelevant categories in database; and 3) preforming discriminative visual search in relevant categories. The proposed algorithm is tested on object search, landmark search, and large-scale similar image search on the large-scale LSVRC10 data set. Although the category clue introduced is weak, our algorithm still shows substantial advantages in retrieval accuracy, efficiency, and memory consumption than the state-of-the-art.

  20. Deployment of low-voltage regulator considering existing voltage control in medium-voltage distribution systems

    Directory of Open Access Journals (Sweden)

    Hiroshi Kikusato

    2016-01-01

    Full Text Available Many photovoltaic (PV systems have been installed in distribution systems. This installation complicates the maintenance of all voltages within the appropriate range in all low-voltage distribution systems (LVDSs because the trends in voltage fluctuation differ in each LVDS. The installation of a low-voltage regulator (LVR that can accordingly control the voltage in each LVDS has been studied as a solution to this problem. Voltage control in a medium-voltage distribution system must be considered to study the deployment of LVRs. In this study, we installed LVRs in the LVDSs in which the existing voltage-control scheme cannot prevent voltage deviation and performed a numerical simulation by using a distribution system model with PV to evaluate the deployment of the LVRs.

  1. Analyzing of Dynamic Voltage Restorer in Series Compensation Voltage

    Directory of Open Access Journals (Sweden)

    Naser Parhizgar

    2012-02-01

    Full Text Available The Dynamic Voltage Restorer (DVR is a series-connected compensator to generate a controllable voltage to against the short-term voltage disturbances. The technique of DVR is an effective and cost competitive approach to improve voltage quality at the load side. This study presents a single-phase and threephase DVR system with reduced switch-count topology to protect the sensitive load against abnormal voltage conditions. Most basic function, the DVR configuration consist of a two level Voltage Source Converter (VSC, a dc energy storage device, a coupling transformer Connected in shunt with the ac system This study presents the application of Dynamic Voltage Restorer (DVR on power distribution systems for mitigation of voltage sag at critical loads. DVR is one of the compensating types of custom power devices. The DVR, which is based on forced-commutated Voltage Source Converter (VSC has been proved suitable for the task of compensating voltage sags/swells. Simulation results are presented to illustrate and understand the performances of DVR in supporting load voltages under voltage sags/swells conditions.

  2. High Voltage Charge Pump

    KAUST Repository

    Emira, Ahmed A.

    2014-10-09

    Various embodiments of a high voltage charge pump are described. One embodiment is a charge pump circuit that comprises a plurality of switching stages each including a clock input, a clock input inverse, a clock output, and a clock output inverse. The circuit further comprises a plurality of pumping capacitors, wherein one or more pumping capacitors are coupled to a corresponding switching stage. The circuit also comprises a maximum selection circuit coupled to a last switching stage among the plurality of switching stages, the maximum selection circuit configured to filter noise on the output clock and the output clock inverse of the last switching stage, the maximum selection circuit further configured to generate a DC output voltage based on the output clock and the output clock inverse of the last switching stage.

  3. Increased voltage photovoltaic cell

    Science.gov (United States)

    Ross, B.; Bickler, D. B.; Gallagher, B. D. (Inventor)

    1985-01-01

    A photovoltaic cell, such as a solar cell, is provided which has a higher output voltage than prior cells. The improved cell includes a substrate of doped silicon, a first layer of silicon disposed on the substrate and having opposite doping, and a second layer of silicon carbide disposed on the first layer. The silicon carbide preferably has the same type of doping as the first layer.

  4. High Voltage Seismic Generator

    Science.gov (United States)

    Bogacz, Adrian; Pala, Damian; Knafel, Marcin

    2015-04-01

    This contribution describes the preliminary result of annual cooperation of three student research groups from AGH UST in Krakow, Poland. The aim of this cooperation was to develop and construct a high voltage seismic wave generator. Constructed device uses a high-energy electrical discharge to generate seismic wave in ground. This type of device can be applied in several different methods of seismic measurement, but because of its limited power it is mainly dedicated for engineering geophysics. The source operates on a basic physical principles. The energy is stored in capacitor bank, which is charged by two stage low to high voltage converter. Stored energy is then released in very short time through high voltage thyristor in spark gap. The whole appliance is powered from li-ion battery and controlled by ATmega microcontroller. It is possible to construct larger and more powerful device. In this contribution the structure of device with technical specifications is resented. As a part of the investigation the prototype was built and series of experiments conducted. System parameter was measured, on this basis specification of elements for the final device were chosen. First stage of the project was successful. It was possible to efficiently generate seismic waves with constructed device. Then the field test was conducted. Spark gap wasplaced in shallowborehole(0.5 m) filled with salt water. Geophones were placed on the ground in straight line. The comparison of signal registered with hammer source and sparker source was made. The results of the test measurements are presented and discussed. Analysis of the collected data shows that characteristic of generated seismic signal is very promising, thus confirms possibility of practical application of the new high voltage generator. The biggest advantage of presented device after signal characteristics is its size which is 0.5 x 0.25 x 0.2 m and weight approximately 7 kg. This features with small li-ion battery makes

  5. A history of chorological categories.

    Science.gov (United States)

    Fattorini, S

    2016-09-01

    One of the purposes of the research program referred to as "systematic biogeography" is the use of species distributions to identify regions and reconstruct biotic area relationships. The reverse, i.e. to group species according to the areas that they live in, leads to the recognition of chorological categories. Biogeographers, working under these two different approaches, have proposed several terms to refer to groups of species that have similar distributions, such as "element", "chorotype" and "component". A historical reconstruction, including semantic observations and philosophical implications, shows that these terms have been used in a variety of senses. The word "component" should not be used in biogeography. The word "element" has been used to identify both a group of species defined according to the biogeographic areas they occupy and a group of species with an assumed shared biogeographic history. It is especially because of the influence of the dispersalist paradigm, which dominated evolutionary thought until the mid-twentieth century, that the second definition has been frequently adopted. The term "element" is therefore ambiguous and its use should always be associated with an explicit definition. The word "chorotype" should be used to define groups of species with similar ranges when no causal assumption is made. The concept of "chorotype," finally, should not be confounded with other concepts such as distributional pattern, cenocron, horofauna, biota, endemic area, area of endemism, biotic element, and generalized track, which are also discussed in this paper.

  6. The additive completion of the biset category

    OpenAIRE

    Ibarra, Jesús; Raggi-Cárdenas, Alberto G.; Romero, Nadia

    2016-01-01

    Let $R$ be a commutative unital ring. We construct a category $\\mathcal{C}_R$ of fractions $X/G$, where $G$ is a finite group and $X$ is a finite $G$-set, and with morphisms given by $R$-linear combinations of spans of bisets. This category is an additive, symmetric monoidal and self-dual category, with a Krull-Schmidt decomposition for objects. We show that $\\mathcal{C}_R$ is equivalent to the additive completion of the biset category and that the category of biset functors over $R$ is equiv...

  7. Mitigation of Voltage Sags in CIGRE Low Voltage Distribution Network

    DEFF Research Database (Denmark)

    Mustafa, Ghullam; Bak-Jensen, Birgitte; Mahat, Pukar;

    2013-01-01

    problems in the distribution system. The voltage problems dealt with in this paper are to show how to mitigate voltage sags in the CIGRE Low Voltage (LV) test network and networks like this. The voltage sags, for the tested cases in the CIGRE LV test network are mainly due to three phase faults....... The compensation of voltage sags in the different parts of CIGRE distribution network is done by using the four STATCOM compensators already existing in the test grid. The simulations are carried out in DIgSILENT power factory software version 15.0....

  8. Voltage Controlled Dynamic Demand Response

    DEFF Research Database (Denmark)

    Bhattarai, Bishnu Prasad; Bak-Jensen, Birgitte; Mahat, Pukar

    2013-01-01

    . An adaptive dynamic model has been developed to determine composite voltage dependency of an aggregated load on feeder level. Following the demand dispatch or control signal, optimum voltage setting at the LV substation is determined based on the voltage dependency of the load. Furthermore, a new technique...

  9. Charge-pump voltage converter

    Science.gov (United States)

    Brainard, John P.; Christenson, Todd R.

    2009-11-03

    A charge-pump voltage converter for converting a low voltage provided by a low-voltage source to a higher voltage. Charge is inductively generated on a transfer rotor electrode during its transit past an inductor stator electrode and subsequently transferred by the rotating rotor to a collector stator electrode for storage or use. Repetition of the charge transfer process leads to a build-up of voltage on a charge-receiving device. Connection of multiple charge-pump voltage converters in series can generate higher voltages, and connection of multiple charge-pump voltage converters in parallel can generate higher currents. Microelectromechanical (MEMS) embodiments of this invention provide a small and compact high-voltage (several hundred V) voltage source starting with a few-V initial voltage source. The microscale size of many embodiments of this invention make it ideally suited for MEMS- and other micro-applications where integration of the voltage or charge source in a small package is highly desirable.

  10. Transient voltage sharing in series-coupled high voltage switches

    Directory of Open Access Journals (Sweden)

    Editorial Office

    1992-07-01

    Full Text Available For switching voltages in excess of the maximum blocking voltage of a switching element (for example, thyristor, MOSFET or bipolar transistor such elements are often coupled in series - and additional circuitry has to be provided to ensure equal voltage sharing. Between each such series element and system ground there is a certain parasitic capacitance that may draw a significant current during high-speed voltage transients. The "open" switch is modelled as a ladder network. Analy­sis reveals an exponential progression in the distribution of the applied voltage across the elements. Overstressing thus oc­curs in some of the elements at levels of the total voltage that are significantly below the design value. This difficulty is overcome by grading the voltage sharing circuitry, coupled in parallel with each element, in a prescribed manner, as set out here.

  11. Feature-Based versus Category-Based Induction with Uncertain Categories

    Science.gov (United States)

    Griffiths, Oren; Hayes, Brett K.; Newell, Ben R.

    2012-01-01

    Previous research has suggested that when feature inferences have to be made about an instance whose category membership is uncertain, feature-based inductive reasoning is used to the exclusion of category-based induction. These results contrast with the observation that people can and do use category-based induction when category membership is…

  12. PRECEDENCE AS A PSYCHOLINGUISTIC CATEGORY

    Directory of Open Access Journals (Sweden)

    Panarina Nadezhda Sergeevna

    2015-06-01

    . In summary, any speech act assumes particular correlation and content of meaning components. Presence of culturological component in meaning structure represents specific nature of speech activity structural elements. Therefore, precedence is a psycholinguistic category, which must be considered taking into account structural features of a particular speech activity.

  13. No-Voltage Meter

    Science.gov (United States)

    1976-02-01

    VW- IKft, 1/4 H4 -Wv- IK!1, I/4W INTERNAL VOLTAGE NOTE ALL TRANSISTORS ARE 2N43A OR EQUIVALENT GERMANIUM ALLOY PNP AA ALKALINE BATTERY...D-,, regardless of polarity. This signal is then full-wave rectified by the diode-connected Germanium transistor bridge, T,, T-,, T3, and T4... Transistor T5 acts as a second current limiter. Resistor R2 was selected to give 90 f# of full-scale meter deflection with an input signal of 115 volts

  14. Benchmarking of Voltage Sag Generators

    DEFF Research Database (Denmark)

    Yang, Yongheng; Blaabjerg, Frede; Zou, Zhixiang

    2012-01-01

    The increased penetration of renewable energy systems, like photovoltaic and wind power systems, rises the concern about the power quality and stability of the utility grid. Some regulations for Low Voltage Ride-Through (LVRT) for medium voltage or high voltage applications, are coming into force...... to guide these grid-connected distributed power generation systems. In order to verify the response of such systems for voltage disturbance, mainly for evaluation of voltage sags/dips, a Voltage Sag Generator (VSG) is needed. This paper evaluates such sag test devices according to IEC 61000 in order...... to provide cheaper solutions to test against voltage sags. Simulation and experimental results demonstrate that the shunt impedance based VSG solution is the easiest and cheapest one for laboratory test applications. The back-to-back fully controlled converter based VSG is the most flexible solution...

  15. Symplectic structures from topological Fukaya categories

    OpenAIRE

    Shende, Vivek; Takeda, Alex

    2016-01-01

    The topological Fukaya category is the global sections of a certain sheaf of categories on a Lagrangian skeleton. Nadler has given a combinatorial description of this sheaf in the case of generic singularities. We show here that restriction to the boundary of this sheaf of categories determines a shifted Lagrangian morphism on the corresponding moduli spaces. Examples of such moduli spaces include wild character varieties, certain cluster varieties, multiplicative Nakajima varieties, and the ...

  16. Coordinated Voltage Control of Distributed PV Inverters for Voltage Regulation in Low Voltage Distribution Networks

    DEFF Research Database (Denmark)

    Nainar, Karthikeyan; Pokhrel, Basanta Raj; Pillai, Jayakrishnan Radhakrishna

    2017-01-01

    This paper reviews and analyzes the existing voltage control methods of distributed solar PV inverters to improve the voltage regulation and thereby the hosting capacity of a low-voltage distribution network. A novel coordinated voltage control method is proposed based on voltage sensitivity...... analysis, which is simple for computation and requires moderate automation and communication infrastructure. The proposed method is suitable for a hierarchical control structure where a supervisory controller has the provision to adapt the settings of local PV inverter controllers for overall system...

  17. Heat-pump performance: voltage dip/sag, under-voltage and over-voltage

    Directory of Open Access Journals (Sweden)

    William J.B. Heffernan

    2014-12-01

    Full Text Available Reverse cycle air-source heat-pumps are an increasingly significant load in New Zealand and in many other countries. This has raised concern over the impact wide-spread use of heat-pumps may have on the grid. The characteristics of the loads connected to the power system are changing because of heat-pumps. Their performance during under-voltage events such as voltage dips has the potential to compound the event and possibly cause voltage collapse. In this study, results from testing six heat-pumps are presented to assess their performance at various voltages and hence their impact on voltage stability.

  18. Deconstructibility and Hill lemma in Grothendieck categories

    CERN Document Server

    Stovicek, Jan

    2010-01-01

    A full subcategory of a Grothendieck category is called deconstructible if it consists of all transfinite extensions of some set of objects. This concept provides a handy framework for structure theory and construction of approximations for subcategories of Grothendieck categories. It also allows to construct model structures and t-structures on categories of complexes over a Grothendieck category. In this paper we aim to establish fundamental results on deconstructible classes and outline how to apply these in the areas mentioned above. This is related to recent work of Gillespie, Enochs, Estrada, Guil Asensio, Murfet, Neeman, Prest, Trlifaj and others.

  19. Some remarks on groupoids and small categories

    CERN Document Server

    Ng, Chi-Keung

    2007-01-01

    This unpublished note contains some materials taken from my old study note on groupoids and small categories. It contains a proof for the fact that any groupoid is a group bundle over an equivalence relation. Moreover, the action of a category $G$ on a category $H$ as well as the resulting semi-direct product category $H\\times_\\alpha G$ will be defined (when either $G$ is a groupoid or $H^{(0)} = G^{(0)}$). If both $G$ and $H$ are groupoids, then $H\\times_\\alpha G$ is also a groupoid. The reason of producing this note is for people who want to check some details in a recent work of Li.

  20. Voltage Swells Improvement in Low Voltage Network Using Dynamic Voltage Restorer

    Directory of Open Access Journals (Sweden)

    R. Omar

    2011-01-01

    Full Text Available Problem statement: Voltage disturbances are the most common power quality problem due to the increased use of a large numbers of sophisticated electronic equipment in industrial distribution system. The voltage disturbances such as voltage sags, swells, harmonics, unbalance and flickers. High quality in the power supply is needed, since failures due to such disturbances usually have a high impact on production cost. There are many different solutions to compensate voltage disturbances but the use of a DVR is considered to be the most cost effective method. The objective of this study is to propose a new topology of a DVR in order to mitigate voltage swells using a powerful power custom device namely the Dynamic Voltage Restorer (DVR. Approach: New configuration of a DVR with an improvement of a controller based on direct-quadrature-zero method has been introduced to compensate voltage swells in the network. Results: The effectiveness of the DVR with its controller were verify using Matlab/Simulinks SimPower Toolbox and then implemented using 5KVA DVR experimental setup. Simulations and experimental results demonstrate the effective dynamic performance of the proposed configuration. Conclusion: The implimentation of the proposed DVR validate the capabilities in mitigating of voltage swells effectiveness.During voltage swells, the DVR injects an appropriate voltage to maintain the load voltage at its nominal value.

  1. Isomerically Pure Tetramethylrhodamine Voltage Reporters.

    Science.gov (United States)

    Deal, Parker E; Kulkarni, Rishikesh U; Al-Abdullatif, Sarah H; Miller, Evan W

    2016-07-27

    We present the design, synthesis, and application of a new family of fluorescent voltage indicators based on isomerically pure tetramethylrhodamines. These new Rhodamine Voltage Reporters, or RhoVRs, use photoinduced electron transfer (PeT) as a trigger for voltage sensing, display excitation and emission profiles in the green to orange region of the visible spectrum, demonstrate high sensitivity to membrane potential changes (up to 47% ΔF/F per 100 mV), and employ a tertiary amide derived from sarcosine, which aids in membrane localization and simultaneously simplifies the synthetic route to the voltage sensors. The most sensitive of the RhoVR dyes, RhoVR 1, features a methoxy-substituted diethylaniline donor and phenylenevinylene molecular wire at the 5'-position of the rhodamine aryl ring, exhibits the highest voltage sensitivity to date for red-shifted PeT-based voltage sensors, and is compatible with simultaneous imaging alongside green fluorescent protein-based indicators. The discoveries that sarcosine-based tertiary amides in the context of molecular-wire voltage indicators prevent dye internalization and 5'-substituted voltage indicators exhibit improved voltage sensitivity should be broadly applicable to other types of PeT-based voltage-sensitive fluorophores.

  2. Quantum subgroups of the Haagerup fusion categories

    CERN Document Server

    Grossman, Pinhas

    2011-01-01

    We answer three related questions concerning the Haagerup subfactor and its even parts, the Haagerup fusion categories. Namely we find all simple module categories over each of the Haagerup fusion categories (in other words, we find the `"quantum subgroups" in the sense of Ocneanu), we find all subfactors whose principal even part is one of the Haagerup fusion categories, and we compute the Brauer-Picard groupoid of Morita equivalences of the Haagerup fusion categories. In addition to the two even parts of the Haagerup subfactor, there is exactly one more fusion category which is Morita equivalent to each of them. This third fusion category has six simple objects and the same fusion rules as one of the even parts of the Haagerup subfactor, but has not previously appeared in the literature. We also find the full lattice of intermediate subfactors for every subfactor whose even part is one of these three fusion categories, and we discuss how our results generalize to Izumi subfactors.

  3. Biased allocation of faces to social categories

    NARCIS (Netherlands)

    Dotsch, R.; Wigboldus, D.H.J.; Knippenberg, A.F.M. van

    2011-01-01

    Three studies show that social categorization is biased at the level of category allocation. In all studies, participants categorized faces. In Studies 1 and 2, participants overallocated faces with criminal features-a stereotypical negative trait-to the stigmatized Moroccan category, especially if

  4. Category-Specificity in Visual Object Recognition

    Science.gov (United States)

    Gerlach, Christian

    2009-01-01

    Are all categories of objects recognized in the same manner visually? Evidence from neuropsychology suggests they are not: some brain damaged patients are more impaired in recognizing natural objects than artefacts whereas others show the opposite impairment. Category-effects have also been demonstrated in neurologically intact subjects, but the…

  5. Category-Specificity in Visual Object Recognition

    Science.gov (United States)

    Gerlach, Christian

    2009-01-01

    Are all categories of objects recognized in the same manner visually? Evidence from neuropsychology suggests they are not: some brain damaged patients are more impaired in recognizing natural objects than artefacts whereas others show the opposite impairment. Category-effects have also been demonstrated in neurologically intact subjects, but the…

  6. Spans in 2-Categories: A monoidal tricategory

    CERN Document Server

    Hoffnung, Alexander E

    2011-01-01

    We present Trimble's definition of a tetracategory and prove that the spans in (strict) 2-categories with certain limits have the structure of a monoidal tricategory, defined as a one-object tetracategory. We recall some notions of limits in 2-categories for use in the construction of the monoidal tricategory of spans.

  7. Finding biomedical categories in Medline®

    Directory of Open Access Journals (Sweden)

    Yeganova Lana

    2012-10-01

    Full Text Available Abstract Background There are several humanly defined ontologies relevant to Medline. However, Medline is a fast growing collection of biomedical documents which creates difficulties in updating and expanding these humanly defined ontologies. Automatically identifying meaningful categories of entities in a large text corpus is useful for information extraction, construction of machine learning features, and development of semantic representations. In this paper we describe and compare two methods for automatically learning meaningful biomedical categories in Medline. The first approach is a simple statistical method that uses part-of-speech and frequency information to extract a list of frequent nouns from Medline. The second method implements an alignment-based technique to learn frequent generic patterns that indicate a hyponymy/hypernymy relationship between a pair of noun phrases. We then apply these patterns to Medline to collect frequent hypernyms as potential biomedical categories. Results We study and compare these two alternative sets of terms to identify semantic categories in Medline. We find that both approaches produce reasonable terms as potential categories. We also find that there is a significant agreement between the two sets of terms. The overlap between the two methods improves our confidence regarding categories predicted by these independent methods. Conclusions This study is an initial attempt to extract categories that are discussed in Medline. Rather than imposing external ontologies on Medline, our methods allow categories to emerge from the text.

  8. Parsing with Structure-Preserving Categorial Grammars

    NARCIS (Netherlands)

    Capelletti, M.

    2007-01-01

    This book is a study of the logical and computational properties of structure-preserving categorial grammars. The first part of the book presents chart-parsers for non-associative categorial grammars in the style of Ajdukiewicz and Bar-Hillel. These are proposed in Chapter 3 as deductive parsers, th

  9. Whitney categories and the Tangle Hypothesis

    CERN Document Server

    Smyth, Conor

    2011-01-01

    We propose a new notion of `n-category with duals', which we call a Whitney n-category. There are two motivations. The first is that Baez and Dolan's Tangle Hypothesis is (almost) tautological when interpreted as a statement about Whitney categories. The second is that we can functorially construct `fundamental Whitney n-categories' from each smooth stratified space X. These are obtained by considering the homotopy theory of smooth maps into X which are transversal to all strata. This makes concrete another idea of Baez and Dolan's which is that a suitable version of homotopy theory for stratified spaces should allow one to generalise the relationship between spaces and groupoids to one between stratified spaces and categories with duals.

  10. Diagnostic Categories in Autobiographical Accounts of Illness.

    Science.gov (United States)

    Kelly, Michael P

    2015-01-01

    Working within frameworks drawn from the writings of Immanuel Kant, Alfred Schutz, and Kenneth Burke, this article examines the role that diagnostic categories play in autobiographical accounts of illness, with a special focus on chronic disease. Four lay diagnostic categories, each with different connections to formal medical diagnostic categories, serve as typifications to make sense of the way the lifeworld changes over the course of chronic illness. These diagnostic categories are used in conjunction with another set of typifications: lay epidemiologies, lay etiologies, lay prognostics, and lay therapeutics. Together these serve to construct and reconstruct the self at the center of the lifeworld. Embedded within the lay diagnostic categories are narratives of progression, regression, or stability, forms of typification derived from literary and storytelling genres. These narratives are developed by the self in autobiographical accounts of illness.

  11. Voltage Dependence of Supercapacitor Capacitance

    Directory of Open Access Journals (Sweden)

    Szewczyk Arkadiusz

    2016-09-01

    Full Text Available Electronic Double-Layer Capacitors (EDLC, called Supercapacitors (SC, are electronic devices that are capable to store a relatively high amount of energy in a small volume comparing to other types of capacitors. They are composed of an activated carbon layer and electrolyte solution. The charge is stored on electrodes, forming the Helmholtz layer, and in electrolyte. The capacitance of supercapacitor is voltage- dependent. We propose an experimental method, based on monitoring of charging and discharging a supercapacitor, which enables to evaluate the charge in an SC structure as well as the Capacitance-Voltage (C-V dependence. The measurement setup, method and experimental results of charging/discharging commercially available supercapacitors in various voltage and current conditions are presented. The total charge stored in an SC structure is proportional to the square of voltage at SC electrodes while the charge on electrodes increases linearly with the voltage on SC electrodes. The Helmholtz capacitance increases linearly with the voltage bias while a sublinear increase of total capacitance was found. The voltage on SC increases after the discharge of electrodes due to diffusion of charges from the electrolyte to the electrodes. We have found that the recovery voltage value is linearly proportional to the initial bias voltage value.

  12. Can height categories replace weight categories in striking martial arts competitions? A pilot study.

    Science.gov (United States)

    Dubnov-Raz, Gal; Mashiach-Arazi, Yael; Nouriel, Ariella; Raz, Raanan; Constantini, Naama W

    2015-09-29

    In most combat sports and martial arts, athletes compete within weight categories. Disordered eating behaviors and intentional pre-competition rapid weight loss are commonly seen in this population, attributed to weight categorization. We examined if height categories can be used as an alternative to weight categories for competition, in order to protect the health of athletes. Height and weight of 169 child and adolescent competitive karate athletes were measured. Participants were divided into eleven hypothetical weight categories of 5 kg increments, and eleven hypothetical height categories of 5 cm increments. We calculated the coefficient of variation of height and weight by each division method. We also calculated how many participants fit into corresponding categories of both height and weight, and how many would shift a category if divided by height. There was a high correlation between height and weight (r = 0.91, p<0.001). The mean range of heights seen within current weight categories was reduced by 83% when participants were divided by height. When allocating athletes by height categories, 74% of athletes would shift up or down one weight category at most, compared with the current categorization method. We conclude that dividing young karate athletes by height categories significantly reduced the range of heights of competitors within the category. Such categorization would not cause athletes to compete against much heavier opponents in most cases. Using height categories as a means to reduce eating disorders in combat sports should be further examined.

  13. The Grothendieck Construction and Gradings for Enriched Categories

    CERN Document Server

    Tamaki, Dai

    2009-01-01

    The Grothendieck construction is a process to form a single category from a diagram of small categories. In this paper, we extend the definition of the Grothendieck construction to diagrams of small categories enriched over a symmetric monoidal category satisfying certain conditions. Symmetric monoidal categories satisfying the conditions in this paper include the category of $k$-modules over a commutative ring $k$, the category of chain complexes, the category of simplicial sets, the category of topological spaces, and the category of modern spectra. In particular, we obtain a generalization of the orbit category construction in [math/0312214]. We also extend the notion of graded categories and show that the Grothendieck construction takes values in the category of graded categories. Our definition of graded category does not require any coproduct decompositions and generalizes $k$-linear graded categories indexed by small categories defined by Lowen. There are two popular ways to construct functors from the...

  14. A Case Study Of Turkish Transmission System For VoltageDips

    DEFF Research Database (Denmark)

    Inan, E.; Alboyaci, B.; Bak, Claus Leth

    2009-01-01

    Power quality problems usually appear in the form of voltage sags, transients and harmonics. From these three broad categories of power quality problems, voltage dips account the most disturbances experienced by industrial customers. Voltage dips generally refer to instantaneous short...... analysis of voltage dip performance of the whole transmission system, is used to compare with results constructed fault statics from SIMPOW DIPS analysis program real data. SIMPOW DIPS software enables to calculate dip frequency for all busses and lines.......-duration voltage variations. The aim of this paper is to have an idea about voltage dip performance of Turkey Transmission System. Turkey's transmission system has 21 regions. For simulations, 2nd region, which includes Istanbul city's area is heavy loaded, is selected. For purposes of early warning and later...

  15. Can height categories replace weight categories in striking martial arts competitions? A pilot study

    Directory of Open Access Journals (Sweden)

    Dubnov-Raz Gal

    2015-09-01

    Full Text Available In most combat sports and martial arts, athletes compete within weight categories. Disordered eating behaviors and intentional pre-competition rapid weight loss are commonly seen in this population, attributed to weight categorization. We examined if height categories can be used as an alternative to weight categories for competition, in order to protect the health of athletes.

  16. Fusion rules of equivariantizations of fusion categories

    OpenAIRE

    2012-01-01

    We determine the fusion rules of the equivariantization of a fusion category $\\mathcal{C}$ under the action of a finite group $G$ in terms of the fusion rules of $\\mathcal{C}$ and group-theoretical data associated to the group action. As an application we obtain a formula for the fusion rules in an equivariantization of a pointed fusion category in terms of group-theoretical data. This entails a description of the fusion rules in any braided group-theoretical fusion category.

  17. A Higher-Order Calculus for Categories

    DEFF Research Database (Denmark)

    Cáccamo, Mario José; Winskel, Glynn

    2001-01-01

    A calculus for a fragment of category theory is presented. The types in the language denote categories and the expressions functors. The judgements of the calculus systematise categorical arguments such as: an expression is functorial in its free variables; two expressions are naturally isomorphic...... in their free variables. There are special binders for limits and more general ends. The rules for limits and ends support an algebraic manipulation of universal constructions as opposed to a more traditional diagrammatic approach. Duality within the calculus and applications in proving continuity are discussed...... with examples. The calculus gives a basis for mechanising a theory of categories in a generic theorem prover like Isabelle....

  18. Shape configuration and category-specificity

    DEFF Research Database (Denmark)

    Gerlach, Christian; Law, I; Paulson, Olaf B.

    2006-01-01

    in difficult object decision tasks, which is also found in the present experiments with outlines, is reversed when the stimuli are fragmented. This interaction between category (natural versus artefacts) and stimulus type (outlines versus fragmented forms) is in accordance with predictions derived from...... a recent account of category-specificity and lends support to the notion that category-specific impairments can occur for both natural objects and artefacts following damage to pre-semantic stages in visual object recognition. The implications of the present findings are discussed in relation to theories...

  19. Affinization of category O for quantum groups

    CERN Document Server

    Young, C A S

    2012-01-01

    Let g be a simple Lie algebra. We consider the category O-hat of those modules over the affine quantum group Uq(g-hat) whose Uq(g)-weights have finite multiplicity and lie in a finite union of cones generated by negative roots. We show that many properties of the category of the finite-dimensional representations naturally extend to the category O-hat. In particular, we develop the theory of q-characters and define the minimal affinizations of parabolic Verma modules. In types ABCFG we classify these minimal affinizations and conjecture a Weyl denominator type formula for their characters.

  20. Fusion rules of equivariantizations of fusion categories

    OpenAIRE

    Burciu, Sebastian; Natale, Sonia

    2012-01-01

    We determine the fusion rules of the equivariantization of a fusion category $\\mathcal{C}$ under the action of a finite group $G$ in terms of the fusion rules of $\\mathcal{C}$ and group-theoretical data associated to the group action. As an application we obtain a formula for the fusion rules in an equivariantization of a pointed fusion category in terms of group-theoretical data. This entails a description of the fusion rules in any braided group-theoretical fusion category.

  1. Comparing two K-category assignments by a K-category correlation coefficient

    DEFF Research Database (Denmark)

    Gorodkin, Jan

    2004-01-01

    Predicted assignments of biological sequences are often evaluated by Matthews correlation coefficient. However, Matthews correlation coefficient applies only to cases where the assignments belong to two categories, and cases with more than two categories are often artificially forced into two...... categories by considering what belongs and what does not belong to one of the categories, leading to the loss of information. Here, an extended correlation coefficient that applies to K-categories is proposed, and this measure is shown to be highly applicable for evaluating prediction of RNA secondary...

  2. Topoi the categorial analysis of logic

    CERN Document Server

    Goldblatt, Robert

    2013-01-01

    A classic exposition of a branch of mathematical logic that uses category theory, this text is suitable for advanced undergraduates and graduate students and accessible to both philosophically and mathematically oriented readers.

  3. Category-specificity in visual object recognition

    DEFF Research Database (Denmark)

    Gerlach, Christian

    2009-01-01

    binding of shape elements into elaborate shape descriptions) and selection (among competing representations in visual long-term memory), which are held to be differentially affected by the structural similarity between objects. Drawing on evidence from clinical studies, experimental studies......Are all categories of objects recognized in the same manner visually? Evidence from neuropsychology suggests they are not: some brain damaged patients are more impaired in recognizing natural objects than artefacts whereas others show the opposite impairment. Category-effects have also been...... demonstrated in neurologically intact subjects, but the findings are contradictory and there is no agreement as to why category-effects arise. This article presents a Pre-semantic Account of Category Effects (PACE) in visual object recognition. PACE assumes two processing stages: shape configuration (the...

  4. Category-specificity in visual object recognition

    DEFF Research Database (Denmark)

    Gerlach, Christian

    2009-01-01

    Are all categories of objects recognized in the same manner visually? Evidence from neuropsychology suggests they are not: some brain damaged patients are more impaired in recognizing natural objects than artefacts whereas others show the opposite impairment. Category-effects have also been...... demonstrated in neurologically intact subjects, but the findings are contradictory and there is no agreement as to why category-effects arise. This article presents a Pre-semantic Account of Category Effects (PACE) in visual object recognition. PACE assumes two processing stages: shape configuration (the...... binding of shape elements into elaborate shape descriptions) and selection (among competing representations in visual long-term memory), which are held to be differentially affected by the structural similarity between objects. Drawing on evidence from clinical studies, experimental studies...

  5. Visual object recognition and category-specificity

    DEFF Research Database (Denmark)

    Gerlach, Christian

    in visual long-term memory. In the thesis it is described how this simple model can account for a wide range of findings on category-specificity in both patients with brain damage and normal subjects. Finally, two hypotheses regarding the neural substrates of the model's components - and how activation......This thesis is based on seven published papers. The majority of the papers address two topics in visual object recognition: (i) category-effects at pre-semantic stages, and (ii) the integration of visual elements into elaborate shape descriptions corresponding to whole objects or large object parts...... (shape configuration). In the early writings these two topics were examined more or less independently. In later works, findings concerning category-effects and shape configuration merge into an integrated model, termed RACE, advanced to explain category-effects arising at pre-semantic stages in visual...

  6. Review of adverb category in Spanish

    Directory of Open Access Journals (Sweden)

    Francisco Javier Satorre Grau

    2009-06-01

    Full Text Available Among all word classes, the adverb is the worst defined and studied grammatical category. All grammarians accept that this category includes very heterogeneous elements, which come from very different origins and have very different functions. There is thus an urgent need to review this grammatical category. With this work, I intend to find an answer to the following questions: How the grammatical theory on the adverb has been developed? Which have been the mistakes of the grammatical tradition by producing a theory on the adverb? What should we actually understand by an adverb? How can we order, in a proper and reasonable way, the elements which are presently grouped in the so called «adverb» category? And finally, is the grammatical theory on the adverb also applicable to adverbial phrases? The result is a rearrangement of the words which have been considered as adverbs by the grammatical tradition so far.

  7. On Gauging Symmetry of Modular Categories

    Science.gov (United States)

    Cui, Shawn X.; Galindo, César; Plavnik, Julia Yael; Wang, Zhenghan

    2016-05-01

    Topological order of a topological phase of matter in two spacial dimensions is encoded by a unitary modular (tensor) category (UMC). A group symmetry of the topological phase induces a group symmetry of its corresponding UMC. Gauging is a well-known theoretical tool to promote a global symmetry to a local gauge symmetry. We give a mathematical formulation of gauging in terms of higher category formalism. Roughly, given a UMC with a symmetry group G, gauging is a 2-step process: first extend the UMC to a G-crossed braided fusion category and then take the equivariantization of the resulting category. Gauging can tell whether or not two enriched topological phases of matter are different, and also provides a way to construct new UMCs out of old ones. We derive a formula for the {H^4} -obstruction, prove some properties of gauging, and carry out gauging for two concrete examples.

  8. Clinical expertise and reasoning with uncertain categories.

    Science.gov (United States)

    Hayes, Brett K; Chen, Tsan-Hsiang Jessamine

    2008-10-01

    Expert clinical psychologists, clinical psychology graduates, and nonclinical graduate students were presented with clinical and nonclinical cases in which the diagnosis or category membership of a character was uncertain; they then made feature predictions about the character. For each case, there was a diagnosis or category that was highly probable and a less likely alternative that either did (relevant condition) or did not (neutral condition) alter predictions. For clinical cases, clinical experts and graduate clinicians gave different predictions for the relevant and neutral conditions, indicating that they had considered the uncertain nature of the diagnosis in their predictions. Although they acknowledged that the diagnosis was uncertain, nonclinical students ignored the less likely diagnostic alternatives when making predictions. For the nonclinical cases, all three groups made predictions based on only the most likely category alternative. The results showed that clinical training and/or experience promote multiple-category reasoning, but that this effect is domain specific.

  9. On Gauging Symmetry of Modular Categories

    Science.gov (United States)

    Cui, Shawn X.; Galindo, César; Plavnik, Julia Yael; Wang, Zhenghan

    2016-12-01

    Topological order of a topological phase of matter in two spacial dimensions is encoded by a unitary modular (tensor) category (UMC). A group symmetry of the topological phase induces a group symmetry of its corresponding UMC. Gauging is a well-known theoretical tool to promote a global symmetry to a local gauge symmetry. We give a mathematical formulation of gauging in terms of higher category formalism. Roughly, given a UMC with a symmetry group G, gauging is a 2-step process: first extend the UMC to a G-crossed braided fusion category and then take the equivariantization of the resulting category. Gauging can tell whether or not two enriched topological phases of matter are different, and also provides a way to construct new UMCs out of old ones. We derive a formula for the {H^4}-obstruction, prove some properties of gauging, and carry out gauging for two concrete examples.

  10. Comparing two K-category assignments by a K-category correlation coefficient.

    Science.gov (United States)

    Gorodkin, J

    2004-12-01

    Predicted assignments of biological sequences are often evaluated by Matthews correlation coefficient. However, Matthews correlation coefficient applies only to cases where the assignments belong to two categories, and cases with more than two categories are often artificially forced into two categories by considering what belongs and what does not belong to one of the categories, leading to the loss of information. Here, an extended correlation coefficient that applies to K-categories is proposed, and this measure is shown to be highly applicable for evaluating prediction of RNA secondary structure in cases where some predicted pairs go into the category "unknown" due to lack of reliability in predicted pairs or unpaired residues. Hence, predicting base pairs of RNA secondary structure can be a three-category problem. The measure is further shown to be well in agreement with existing performance measures used for ranking protein secondary structure predictions. Server and software is available at http://rk.kvl.dk/.

  11. Rapid object category adaptation during unlabelled classification.

    Science.gov (United States)

    Hadas, David; Intrator, Nathan; Yovel, Galit

    2010-01-01

    Recent reports from electrophysiological and psychophysical experiments provide evidence that repeated exposure to an ordered sequence of morphed stimuli may over time adapt a prelearned object category such that the category may generalise the entire sequence as belonging to the same object. Here, a new protocol that includes a single exposure to a morphing sequence is presented. Subjects exposed to the new protocol replaced a prelearned face with an entirely different face within just 3 days, significantly faster than in previous reports.

  12. Experiences with the ISOcat Data Category Registry

    OpenAIRE

    Broeder, Daan; Schuurman, Ineke; Windhouwer, Menzo; Chair), Nicoletta Calzolari (Conference; Choukri, Khalid; Declerck, Thierry; Loftsson, Hrafn; Maegaard, Bente; Mariani, Joseph; Moreno, Asuncion; Odijk, Jan; Piperidis, Stelios

    2014-01-01

    The ISOcat Data Category Registry has been a joint project of both ISO TC 37 and the European CLARIN infrastructure. In this paper the experiences of using ISOcat in CLARIN are described and evaluated. This evaluation clarifies the requirements of CLARIN with regard to a semantic registry to support its semantic interoperability needs. A simpler model based on concepts instead of data categories and a simpler workflow based on community recommendations will address these needs better and offe...

  13. Experiences with the ISOcat Data Category Registry

    OpenAIRE

    Broeder, Daan; Schuurman, Ineke; Windhouwer, Menzo

    2014-01-01

    The ISOcat Data Category Registry has been a joint project of both ISO TC 37 and the European CLARIN infrastructure. In this paper the experiences of using ISOcat in CLARIN are described and evaluated. This evaluation clarifies the requirements of CLARIN with regard to a semantic registry to support its semantic interoperability needs. A simpler model based on concepts instead of data cate-gories and a simpler workflow based on community recommendations will address these needs better and off...

  14. Defining an m-cluster category

    OpenAIRE

    Thomas, Hugh

    2006-01-01

    We show that a certain orbit category considerd by Keller encodes the combinatorics of the $m$-clusters of Fomin and Reading in a fashion similar to the way the cluster category of Buan, Marsh, Reineke, Reiten, and Todorov encodes the combinatorics of the clusters of Fomin and Zelevinsky. This allows us to give type-uniform proofs of certain results of Fomin and Reading in the simply laced cases.

  15. Mixed quantum states in higher categories

    Directory of Open Access Journals (Sweden)

    Chris Heunen

    2014-12-01

    Full Text Available There are two ways to describe the interaction between classical and quantum information categorically: one based on completely positive maps between Frobenius algebras, the other using symmetric monoidal 2-categories. This paper makes a first step towards combining the two. The integrated approach allows a unified description of quantum teleportation and classical encryption in a single 2-category, as well as a universal security proof applicable simultaneously to both scenarios.

  16. Learning, retention, and generalization of haptic categories

    Science.gov (United States)

    Do, Phuong T.

    This dissertation explored how haptic concepts are learned, retained, and generalized to the same or different modality. Participants learned to classify objects into three categories either visually or haptically via different training procedures, followed by an immediate or delayed transfer test. Experiment I involved visual versus haptic learning and transfer. Intermodal matching between vision and haptics was investigated in Experiment II. Experiments III and IV examined intersensory conflict in within- and between-category bimodal situations to determine the degree of perceptual dominance between sight and touch. Experiment V explored the intramodal relationship between similarity and categorization in a psychological space, as revealed by MDS analysis of similarity judgments. Major findings were: (1) visual examination resulted in relatively higher performance accuracy than haptic learning; (2) systematic training produced better category learning of haptic concepts across all modality conditions; (3) the category prototypes were rated newer than any transfer stimulus followed learning both immediately and after a week delay; and, (4) although they converged at the apex of two transformational trajectories, the category prototypes became more central to their respective categories and increasingly structured as a function of learning. Implications for theories of multimodal similarity and categorization behavior are discussed in terms of discrimination learning, sensory integration, and dominance relation.

  17. Categories of difference in science and policy

    DEFF Research Database (Denmark)

    Jørgensen, Martin Bak

    2012-01-01

    Categories of difference have a crucial position in academic research as well as policymaking. They serve to distinguish and differentiate between groups in society. They can appear in the shape of crude dichotomies or in complex and sophisticated forms resting on constructivist and intersectiona......Categories of difference have a crucial position in academic research as well as policymaking. They serve to distinguish and differentiate between groups in society. They can appear in the shape of crude dichotomies or in complex and sophisticated forms resting on constructivist...... and intersectionalist perspectives. Nevertheless, using categories of difference also creates something into existence and there may be implications through the particular application of specific categories. This article reflects on how categories of difference are constructed and employed in research, legislation...... and policy discourse. By looking at different approaches used by qualitative and quantitative researchers, as well as at how specific concepts enter policy-making and legislation, I want to address a number of questions about how we as researchers understand and work with categories of differences...

  18. On the flexibility of phonetic categories

    Science.gov (United States)

    Francis, Alexander L.; Nusbaum, Howard C.

    2002-05-01

    Research on phonetic category acquisition suggests that over the course of development children shift the relative weight given to various acoustic cues to particular phonetic categories [S. Nittrouer, J. Phon. 20, 1-32 (1992)]. Adults also show flexibility in acquiring second language categories and learning to recognize synthetic speech. In both cases listeners must shift attention among some acoustic cues and change the weighting and mapping of others. Recent research demonstrated that category-level feedback can induce adult listeners to shift attention between conflicting cues to native stop-consonant categories. Subsequent research showed that adult listeners also reorganize the distribution of their attention to acoustic cues in learning to better understand synthetic speech. Moreover, research on learning foreign phonetic contrasts suggests that listeners can learn to direct attention to unfamiliar acoustic cues. These results suggest that phonetic categories are flexible in terms of the nature and quality of the acoustic cues that define them. We argue that this flexibility is a consequence of the basic nature of the general mechanism that mediates speech perception: In order to resolve the problem of context-conditioned variability, listeners must dynamically modify attention to the acoustic signal in a context-dependent manner.

  19. Monoidal categories and topological field theory

    CERN Document Server

    Turaev, Vladimir

    2017-01-01

    This monograph is devoted to monoidal categories and their connections with 3-dimensional topological field theories. Starting with basic definitions, it proceeds to the forefront of current research. Part 1 introduces monoidal categories and several of their classes, including rigid, pivotal, spherical, fusion, braided, and modular categories. It then presents deep theorems of Müger on the center of a pivotal fusion category. These theorems are proved in Part 2 using the theory of Hopf monads. In Part 3 the authors define the notion of a topological quantum field theory (TQFT) and construct a Turaev-Viro-type 3-dimensional state sum TQFT from a spherical fusion category. Lastly, in Part 4 this construction is extended to 3-manifolds with colored ribbon graphs, yielding a so-called graph TQFT (and, consequently, a 3-2-1 extended TQFT). The authors then prove the main result of the monograph: the state sum graph TQFT derived from any spherical fusion category is isomorphic to the Reshetikhin-Turaev surgery gr...

  20. Voltage Sensors Monitor Harmful Static

    Science.gov (United States)

    2009-01-01

    A tiny sensor, small enough to be worn on clothing, now monitors voltage changes near sensitive instruments after being created to alert Agency workers to dangerous static buildup near fuel operations and avionics. San Diego s Quasar Federal Systems received a Small Business Innovation Research (SBIR) contract from Kennedy Space Center to develop its remote voltage sensor (RVS), a dime-sized electrometer designed to measure triboelectric changes in the environment. One of the unique qualities of the RVS is that it can detect static at greater distances than previous devices, measuring voltage changes from a few centimeters to a few meters away, due to its much-improved sensitivity.

  1. Low Voltage Power Supply Incorporating Ceramic Transformer

    CERN Document Server

    Imori, M

    2007-01-01

    A low voltage power supply provides the regulated output voltage of 1 V from the supply voltage around 48 V. The low voltage power supply incorporates a ceramic transformer which utilizes piezoelectric effect to convert voltage. The ceramic transformer isolates the secondary from the primary, thus providing the ground isolation between the supply and the output voltages. The ceramic transformer takes the place of the conventional magnetic transformer. The ceramic transformer is constructed from a ceramic bar and does not include any magnetic material. So the low voltage power supply can operate under a magnetic field. The output voltage is stabilized by feedback. A feedback loop consists of an error amplifier, a voltage controlled oscillator and a driver circuit. The amplitude ratio of the transformer has dependence on the frequency, which is utilized to stabilize the output voltage. The low voltage power supply is investigated on the analogy of the high voltage power supply similarly incorporating the cerami...

  2. Modular High Voltage Power Supply

    Energy Technology Data Exchange (ETDEWEB)

    Newell, Matthew R. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-05-18

    The goal of this project is to develop a modular high voltage power supply that will meet the needs of safeguards applications and provide a modular plug and play supply for use with standard electronic racks.

  3. An "almost" full embedding of the category of graphs into the category of abelian groups

    CERN Document Server

    Przezdziecki, Adam J

    2011-01-01

    We construct an embedding G of the category of graphs into the category of abelian groups such that for graphs X and Y we have Hom(GX,GY)=Z[Hom(X,Y)], the free abelian group whose basis is the set Hom(X,Y). The isomorphism is functorial in X and Y. The existence of such an embedding implies that, contrary to a common belief, the category of abelian groups is as complex and comprehensive as any other concrete category. We use this embedding to settle an old problem of Isbell whether every full subcategory of the category of abelian groups, which is closed under limits, is reflective. A positive answer turns out to be equivalent to weak Vopenka's principle, a large cardinal axiom which is not provable but believed to be consistent with standard set theory. Several known constructions in the category of abelian groups are obtained as quick applications of the embedding.

  4. Reliability criteria for voltage stability

    Energy Technology Data Exchange (ETDEWEB)

    Taylor, Carson W.; Silverstein, Brian L. [Bonneville Power Administration, Portland, OR (United States)

    1994-12-31

    In face of costs pressures, there is need to allocate scare resources more effectively in order to achieve voltage stability. This naturally leads to development of probabilistic criteria and notions of rick management. In this paper it is presented a discussion about criteria for long term voltage stability limited to the case in which the time frames are topically several minutes. (author) 14 refs., 1 fig.

  5. A Voltage Quality Detection Method

    DEFF Research Database (Denmark)

    Chen, Zhe; Wei, Mu

    2008-01-01

    This paper presents a voltage quality detection method based on a phase-locked loop (PLL) technique. The technique can detect the voltage magnitude and phase angle of each individual phase under both normal and fault power system conditions. The proposed method has the potential to evaluate vario...... power quality disturbances, such as interruptions, sags and imbalances. Simulation studies have been performed. The effectiveness of the proposed method has been demonstrated under the simulated typical power disturbances....

  6. A matter of quantum voltages.

    Science.gov (United States)

    Sellner, Bernhard; Kathmann, Shawn M

    2014-11-14

    Voltages inside matter are relevant to crystallization, materials science, biology, catalysis, and aqueous chemistry. The variation of voltages in matter can be measured by experiment, however, modern supercomputers allow the calculation of accurate quantum voltages with spatial resolutions of bulk systems well beyond what can currently be measured provided a sufficient level of theory is employed. Of particular interest is the Mean Inner Potential (V(o))--the spatial average of these quantum voltages referenced to the vacuum. Here we establish a protocol to reliably evaluate V(o) from quantum calculations. Voltages are very sensitive to the distribution of electrons and provide metrics to understand interactions in condensed phases. In the present study, we find excellent agreement with measurements of V(o) for vitrified water and salt crystals and demonstrate the impact of covalent and ionic bonding as well as intermolecular/atomic interactions. Certain aspects in this regard are highlighted making use of simple model systems/approximations. Furthermore, we predict V(o) as well as the fluctuations of these voltages in aqueous NaCl electrolytes and characterize the changes in their behavior as the resolution increases below the size of atoms.

  7. Symmetric centres of braided monoidal categories

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    This paper introduces the concept of‘symmetric centres' of braided monoidal categories. Let H be a Hopf algebra with bijective antipode over a field k. We address the symmetric centre of the Yetter-Drinfel'd module category HH(yD) and show that a left Yetter-Drinfel'd module M belongs to the symmetric centre of HH(yD) if and only if M is trivial. We also study the symmetric centres of categories of representations of quasitriangular Hopf algebras and give a sufficient and necessary condition for the braid of H(M) to induce the braid of (H(H)(A),(○)A,A,φ,l,r), or equivalently, the braid of (A#H(H),(○)A,A,φ,l,r), where A is a quantum commutative H-module algebra.

  8. Concepts and categories: a cognitive neuropsychological perspective.

    Science.gov (United States)

    Mahon, Bradford Z; Caramazza, Alfonso

    2009-01-01

    One of the most provocative and exciting issues in cognitive science is how neural specificity for semantic categories of common objects arises in the functional architecture of the brain. More than two decades of research on the neuropsychological phenomenon of category-specific semantic deficits has generated detailed claims about the organization and representation of conceptual knowledge. More recently, researchers have sought to test hypotheses developed on the basis of neuropsychological evidence with functional imaging. From those two fields, the empirical generalization emerges that object domain and sensory modality jointly constrain the organization of knowledge in the brain. At the same time, research within the embodied cognition framework has highlighted the need to articulate how information is communicated between the sensory and motor systems, and processes that represent and generalize abstract information. Those developments point toward a new approach for understanding category specificity in terms of the coordinated influences of diverse regions and cognitive systems.

  9. Multimedia category preferences of working engineers

    Science.gov (United States)

    Baukal, Charles E.; Ausburn, Lynna J.

    2016-09-01

    Many have argued for the importance of continuing engineering education (CEE), but relatively few recommendations were found in the literature for how to use multimedia technologies to deliver it most effectively. The study reported here addressed this gap by investigating the multimedia category preferences of working engineers. Four categories of multimedia, with two types in each category, were studied: verbal (text and narration), static graphics (drawing and photograph), dynamic non-interactive graphics (animation and video), and dynamic interactive graphics (simulated virtual reality (VR) and photo-real VR). The results showed that working engineers strongly preferred text over narration and somewhat preferred drawing over photograph, animation over video, and simulated VR over photo-real VR. These results suggest that a variety of multimedia types should be used in the instructional design of CEE content.

  10. Grammatical category dissociation in multilingual aphasia.

    Science.gov (United States)

    Faroqi-Shah, Yasmeen; Waked, Arifi N

    2010-03-01

    Word retrieval deficits for specific grammatical categories, such as verbs versus nouns, occur as a consequence of brain damage. Such deficits are informative about the nature of lexical organization in the human brain. This study examined retrieval of grammatical categories across three languages in a trilingual person with aphasia who spoke Arabic, French, and English. In order to delineate the nature of word production difficulty, comprehension was tested, and a variety of concomitant lexical-semantic variables were analysed. The patient demonstrated a consistent noun-verb dissociation in picture naming and narrative speech, with severely impaired production of verbs across all three languages. The cross-linguistically similar noun-verb dissociation, coupled with little evidence of semantic impairment, suggests that (a) the patient has a true "nonsemantic" grammatical category specific deficit, and (b) lexical organization in multilingual speakers shares grammatical class information between languages. The findings of this study contribute to our understanding of the architecture of lexical organization in bilinguals.

  11. Structural similarity and category-specificity

    DEFF Research Database (Denmark)

    Gerlach, Christian; Law, Ian; Paulson, Olaf B

    2004-01-01

    It has been suggested that category-specific recognition disorders for natural objects may reflect that natural objects are more structurally (visually) similar than artefacts and therefore more difficult to recognize following brain damage. On this account one might expect a positive relationship...... between blood flow and structural similarity in areas involved in visual object recognition. Contrary to this expectation we report a negative relationship in that identification of articles of clothing cause more extensive activation than identification of vegetables/fruit and animals even though items...... from the categories of animals and vegetables/fruit are rated as more structurally similar than items from the category of articles of clothing. Given that this pattern cannot be explained in terms of a tradeoff between activation and accuracy, we interpret these findings within a model where...

  12. From Perceptual Categories to Concepts: What Develops?

    Science.gov (United States)

    Sloutsky, Vladimir M

    2010-09-01

    People are remarkably smart: they use language, possess complex motor skills, make non-trivial inferences, develop and use scientific theories, make laws, and adapt to complex dynamic environments. Much of this knowledge requires concepts and this paper focuses on how people acquire concepts. It is argued that conceptual development progresses from simple perceptual grouping to highly abstract scientific concepts. This proposal of conceptual development has four parts. First, it is argued that categories in the world have different structure. Second, there might be different learning systems (sub-served by different brain mechanisms) that evolved to learn categories of differing structures. Third, these systems exhibit differential maturational course, which affects how categories of different structures are learned in the course of development. And finally, an interaction of these components may result in the developmental transition from perceptual groupings to more abstract concepts. This paper reviews a large body of empirical evidence supporting this proposal.

  13. Categories of difference in science and policy

    DEFF Research Database (Denmark)

    Jørgensen, Martin Bak

    2012-01-01

    Categories of difference have a crucial position in academic research as well as policymaking. They serve to distinguish and differentiate between groups in society. They can appear in the shape of crude dichotomies or in complex and sophisticated forms resting on constructivist and intersectiona......Categories of difference have a crucial position in academic research as well as policymaking. They serve to distinguish and differentiate between groups in society. They can appear in the shape of crude dichotomies or in complex and sophisticated forms resting on constructivist...... and policy discourse. By looking at different approaches used by qualitative and quantitative researchers, as well as at how specific concepts enter policy-making and legislation, I want to address a number of questions about how we as researchers understand and work with categories of differences...

  14. VOLTAGE COMPENSATION USING ARTIFICIAL NEURAL NETWORK

    African Journals Online (AJOL)

    VOLTAGE COMPENSATION USING ARTIFICIAL NEURAL NETWORK: A CASE STUDY OF RUMUOLA DISTRIBUTION NETWORK. ... The artificial neural networks controller engaged to controlling the dynamic voltage ... Article Metrics.

  15. Protein secondary structure: category assignment and predictability

    DEFF Research Database (Denmark)

    Andersen, Claus A.; Bohr, Henrik; Brunak, Søren

    2001-01-01

    In the last decade, the prediction of protein secondary structure has been optimized using essentially one and the same assignment scheme known as DSSP. We present here a different scheme, which is more predictable. This scheme predicts directly the hydrogen bonds, which stabilize the secondary...... structures. Single sequence prediction of the new three category assignment gives an overall prediction improvement of 3.1% and 5.1%, compared to the DSSP assignment and schemes where the helix category consists of a-helix and 3(10)-helix, respectively. These results were achieved using a standard feed...

  16. Shape configuration and category-specificity

    DEFF Research Database (Denmark)

    Gerlach, Christian; Law, Ian; Paulson, Olaf B

    2006-01-01

    and fragmented drawings. We also examined whether fragmentation had different impact on the recognition of natural objects and artefacts and found that recognition of artefacts was more affected by fragmentation than recognition of natural objects. Thus, the usual finding of an advantage for artefacts...... a recent account of category-specificity and lends support to the notion that category-specific impairments can occur for both natural objects and artefacts following damage to pre-semantic stages in visual object recognition. The implications of the present findings are discussed in relation to theories...

  17. Derived Categories and Zero-Brane Stability

    Energy Technology Data Exchange (ETDEWEB)

    Lawrence, Albion

    2001-07-25

    We define a particular class of topological field theories associated to open strings and prove the resulting D-branes and open strings form the bounded derived category of coherent sheaves. This derivation is a variant of some ideas proposed recently by Douglas. We then argue that any 0-brane on any Calabi-Yau threefold must become unstable along some path in the Kahler moduli space. As a byproduct of this analysis we see how the derived category can be invariant under a birational transformation.

  18. Retail beer market. Opportunities for beer category

    OpenAIRE

    Caldová, Marie

    2015-01-01

    My bachelors thesis deals with design of better utilization of sales space in traditional retail formats. I focus on the beer category . I describe the basic principles of retailing. I imagine the food retailing division according to the company Pilsner Urquell. I mention all the legal requirements for the labeling of beer products. I mention the beer category share in total sales in the retail market . I describe the main beer producers who are active on the Czech market. The main topic is t...

  19. Coherence for Skew-Monoidal Categories

    Directory of Open Access Journals (Sweden)

    Tarmo Uustalu

    2014-06-01

    Full Text Available I motivate a variation (due to K. Szlachányi of monoidal categories called skew-monoidal categories where the unital and associativity laws are not required to be isomorphisms, only natural transformations. Coherence has to be formulated differently than in the well-known monoidal case. In my (to my knowledge new version, it becomes a statement of uniqueness of normalizing rewrites. I present a proof of this coherence theorem and also formalize it fully in the dependently typed programming language Agda.

  20. Category number impacts rule-based and information-integration category learning: a reassessment of evidence for dissociable category-learning systems.

    Science.gov (United States)

    Stanton, Roger D; Nosofsky, Robert M

    2013-07-01

    Researchers have proposed that an explicit reasoning system is responsible for learning rule-based category structures and that a separate implicit, procedural-learning system is responsible for learning information-integration category structures. As evidence for this multiple-system hypothesis, researchers report a dissociation based on category-number manipulations in which rule-based category learning is worse when the category is composed of 4, rather than 2, response categories; however, information-integration category learning is unaffected by category-number manipulations. We argue that within the reported category-number manipulations, there exists a critical confound: Perceptual clusters used to construct the categories are spread apart in the 4-category condition relative to the 2-category one. The present research shows that when this confound is eliminated, performance on information-integration category learning is worse for 4 categories than for 2 categories, and this finding is demonstrated across 2 different information-integration category structures. Furthermore, model-based analyses indicate that a single-system learning model accounts well for both the original findings and the updated experimental findings reported here.

  1. Biased allocation of faces to social categories.

    Science.gov (United States)

    Dotsch, Ron; Wigboldus, Daniël H J; van Knippenberg, Ad

    2011-06-01

    Three studies show that social categorization is biased at the level of category allocation. In all studies, participants categorized faces. In Studies 1 and 2, participants overallocated faces with criminal features--a stereotypical negative trait--to the stigmatized Moroccan category, especially if they were prejudiced. On the contrary, the stereotype-irrelevant negative trait stupid did not lead to overallocation to the Moroccan category. In Study 3, using the stigmatized category homosexual, the previously used negative trait criminal--irrelevant to the homosexual stereotype--did not lead to overallocation, but the stereotype-relevant positive trait femininity did. These results demonstrate that normative fit is higher for faces with stereotype-relevant features regardless of valence. Moreover, individual differences in implicit prejudice predicted the extent to which stereotype-relevant traits elicited overallocation: Whereas more negatively prejudiced people showed greater overallocation of faces associated with negative stereotype-relevant traits, they showed less overallocation of faces associated with positive stereotype-relevant traits. These results support our normative fit hypothesis: In general, normative fit is better for faces with stereotypical features. Moreover, normative fit is enhanced for prejudiced individuals when these features are evaluatively congruent. Social categorization thus may be biased in itself.

  2. Reasoning with Polarity in Categorial Type Logic

    NARCIS (Netherlands)

    Bernardi, R.A.

    2002-01-01

    The research presented in this thesis follows the parsing as deduction approach to lin- guistics. We use the tools of Categorial Type Logic (CTL) to study the interface of natural language syntax and semantics. Our aim is to investigate the mathematical structure of CTL and explore the possibilities

  3. The Schetic Categories of the Tlingit Verb.

    Science.gov (United States)

    Leer, Jeffry A.

    An analysis of verbs in Tlingit, a U.S. Northwest Coast Indian language, begins with an overview of its situation and usage and of previous research. The second chapter sketches its phonological and syntactic characteristics. Subsequent chapters deal specifically with the verb. An analysis of verb categories distinguishes two groups: argumental…

  4. Measuring Category Intuitiveness in Unconstrained Categorization Tasks

    Science.gov (United States)

    Pothos, Emmanuel M.; Perlman, Amotz; Bailey, Todd M.; Kurtz, Ken; Edwards, Darren J.; Hines, Peter; McDonnell, John V.

    2011-01-01

    What makes a category seem natural or intuitive? In this paper, an unsupervised categorization task was employed to examine observer agreement concerning the categorization of nine different stimulus sets. The stimulus sets were designed to capture different intuitions about classification structure. The main empirical index of category…

  5. Multimedia Category Preferences of Working Engineers

    Science.gov (United States)

    Baukal, Charles E., Jr.; Ausburn, Lynna J.

    2016-01-01

    Many have argued for the importance of continuing engineering education (CEE), but relatively few recommendations were found in the literature for how to use multimedia technologies to deliver it most effectively. The study reported here addressed this gap by investigating the multimedia category preferences of working engineers. Four categories…

  6. Equivalence of D-brane categories

    NARCIS (Netherlands)

    Quintero Velez, A.

    2009-01-01

    In this thesis certain aspects of D-branes and their role in a deeper understanding of gauged linear sigma models and quiver gauge theories are investigated, including the relevant categories in the mathematical setup. Our applications include the development of a McKay correspondence for Landau-Gin

  7. Gorensteinness and Tate Cohomology in Exact Categories

    Institute of Scientific and Technical Information of China (English)

    WANG Zhi-cheng

    2015-01-01

    Motivated by the classical Gorenstein homological theory and structure of Tate cohomology, we develop a theory of Gorenstein projective objects and Tate cohomology in an exact category A with enough projectives. We study some properties of Gorenstein projective objects and establish Tate cohomology of objects with finite Gorenstein projective dimension.

  8. Reliability of Multi-Category Rating Scales

    Science.gov (United States)

    Parker, Richard I.; Vannest, Kimberly J.; Davis, John L.

    2013-01-01

    The use of multi-category scales is increasing for the monitoring of IEP goals, classroom and school rules, and Behavior Improvement Plans (BIPs). Although they require greater inference than traditional data counting, little is known about the inter-rater reliability of these scales. This simulation study examined the performance of nine…

  9. Commutativity and ideals in category crossed products

    DEFF Research Database (Denmark)

    Öinert, Per Johan; Lundström, Patrik

    2010-01-01

    In order to simultaneously generalize matrix rings and group graded crossed products, we introduce category crossed products. For such algebras we describe the centre and the commutant of the coefficient ring. We also investigate the connection between on the one hand maximal commutativity of the...

  10. Ontological semantics in modified categorial grammar

    DEFF Research Database (Denmark)

    Szymczak, Bartlomiej Antoni

    2009-01-01

    Categorial Grammar is a well established tool for describing natural language semantics. In the current paper we discuss some of its drawbacks and how it could be extended to overcome them. We use the extended version for deriving ontological semantics from text. A proof-of-concept implementation...

  11. Toward theory-based diagnostic categories.

    Science.gov (United States)

    Gordon, M

    1990-01-01

    As a social institution, nursing has a responsibility to society for the development of knowledge in the areas described by nursing diagnoses. This article focuses on the need for developing the theoretical basis of each diagnostic category. Diagnoses are viewed as summarizations of underlying conceptual models for interpreting observations, and as such, they provide a perspective for understanding and thinking about a set of clinical observations. At present many diagnostic concepts do not meet this standard and suggest primitive, pretheoretical ideas with a minimal knowledge base. The importance of having valid and reliable diagnostic categories for use in making clinical judgements and as a focus for care planning is discussed. A cycle of development is outlined in three phases: diagnostic concept identification, concept analysis-model development, and construction/reconstruction of diagnostic categories. It is suggested that a useful category captures the conceptual understanding and state of knowledge development about a phenomena in its (a) name, (b) definition, and (c) cluster of defining characteristics.

  12. Language specific bootstraps for UG categories

    NARCIS (Netherlands)

    van Kampen, N.J.

    2005-01-01

    This paper argues that the universal categories N/V are not applied to content words before the grammatical markings for reference D(eterminers) and predication I(nflection) have been acquired (van Kampen, 1997, contra Pinker, 1984). Child grammar starts as proto-grammar with language-specific opera

  13. Social categories are shaped by social experience.

    Science.gov (United States)

    Waxman, Sandra R

    2012-11-01

    A new study by Rhodes and colleagues offers insight into the development of social essentialism - the belief that members of social categories share essential properties (e.g., attitudes, psychological capacities). The challenge now is to consider these issues in children raised in the more diverse social environments that constitute the range of human experience.

  14. Empire: An Analytical Category for Educational Research

    Science.gov (United States)

    Coloma, Roland Sintos

    2013-01-01

    In this article Roland Sintos Coloma argues for the relevance of empire as an analytical category in educational research. He points out the silence in mainstream studies of education on the subject of empire, the various interpretive approaches to deploying empire as an analytic, and the importance of indigeneity in research on empire and…

  15. Family Factors Predicting Categories of Suicide Risk

    Science.gov (United States)

    Randell, Brooke P.; Wang, Wen-Ling; Herting, Jerald R.; Eggert, Leona L.

    2006-01-01

    We compared family risk and protective factors among potential high school dropouts with and without suicide-risk behaviors (SRB) and examined the extent to which these factors predict categories of SRB. Subjects were randomly selected from among potential dropouts in 14 high schools. Based upon suicide-risk status, 1,083 potential high school…

  16. Electrode voltage fall and total voltage of a transient arc

    Science.gov (United States)

    Valensi, F.; Ratovoson, L.; Razafinimanana, M.; Masquère, M.; Freton, P.; Gleizes, A.

    2016-06-01

    This paper deals with an experimental study of the components of a transient arc total voltage with duration of a few tens of ms and a current peak close to 1000 A. The cathode tip is made of graphite whereas the flat anode is made either of copper or of graphite; the electrodes gap is a few mm. The analysis of the electrical parameters is supported and validated by fast imaging and by two models: the first one is a 2D physical model of the arc allowing to calculate both the plasma temperature field and the arc voltage; the second model is able to estimate the transient heating of the graphite electrode. The main aim of the study was to detect the possible change of the cathode voltage fall (CVF) during the first instants of the arc. Indeed it is expected that during the first ms the graphite cathode is rather cool and the main mechanism of the electron emission should be the field effect emission, whereas after several tens of ms the cathode is strongly heated and thermionic emission should be predominant. We have observed some change in the apparent CVF but we have shown that this apparent change can be attributed to the variation of the solid cathode resistance. On the other hand, the possible change of CVF corresponding to the transition between a ‘cold’ and a ‘hot’ cathode should be weak and could not be characterized considering our measurement uncertainty of about 2 V. The arc column voltage (ACV) was estimated by subtracting the electrode voltage fall from the total arc voltage. The experimental transient evolution of the ACV is in very good agreement with the theoretical variation predicted by the model, showing the good ability of the model to study this kind of transient arc.

  17. Unbalanced Voltage Compensation in Low Voltage Residential AC Grids

    DEFF Research Database (Denmark)

    Trintis, Ionut; Douglass, Philip; Munk-Nielsen, Stig

    2016-01-01

    This paper describes the design and test of a control algorithm for active front-end rectifiers that draw power from a residential AC grid to feed heat pump loads. The control algorithm is able to control the phase to neutral or phase to phase RMS voltages at the point of common coupling....... The voltage control was evaluated with either active or reactive independent phase load current control. The control performance in field operation in a residential grid situated in Bornholm, Denmark was investigated for different use cases....

  18. Automated Voltage Control in LHCb

    CERN Document Server

    Granado Cardoso, L; Jacobsson, R

    2011-01-01

    LHCb is one of the 4 LHC experiments. In order to ensure the safety of the detector and to maximize efficiency, LHCb needs to coordinate its own operations, in particular the voltage configuration of the different subdetectors, according to the accelerator status. A control software has been developed for this purpose, based on the Finite State Machine toolkit and the SCADA system used for control throughout LHCb (and the other LHC experiments). This software permits to efficiently drive both the Low Voltage (LV) and High Voltage (HV) systems of the 10 different sub-detectors that constitute LHCb, setting each sub-system to the required voltage (easily configurable at run-time) based on the accelerator state. The control software is also responsible for monitoring the state of the Sub-detector voltages and adding it to the event data in the form of status-bits. Safe and yet flexible operation of the LHCb detector has been obtained and automatic actions, triggered by the state changes of the ...

  19. Development of a New Cascade Voltage-Doubler for Voltage Multiplication

    OpenAIRE

    Arash Toudeshki; Norman Mariun; Hashim Hizam; Noor Izzri Abdul Wahab

    2014-01-01

    For more than eight decades, cascade voltage-doubler circuits are used as a method to produce DC output voltage higher than the input voltage. In this paper, the topological developments of cascade voltage-doublers are reviewed. A new circuit configuration for cascade voltage-doubler is presented. This circuit can produce a higher value of the DC output voltage and better output quality compared to the conventional cascade voltage-doubler circuits, with the same number of stages.

  20. Low-Energy Real-Time OS Using Voltage Scheduling Algorithm for Variable Voltage Processors

    OpenAIRE

    Okuma, Takanori; Yasuura, Hiroto

    2001-01-01

    This paper presents a real-time OS based on $ mu $ITRON using proposed voltage scheduling algorithm for variable voltage processors which can vary supply voltage dynamically. The proposed voltage scheduling algorithms assign voltage level for each task dynamically in order to minimize energy consumption under timing constraints. Using the presented real-time OS, running tasks with low supply voltage leads to drastic energy reduction. In addition, the presented voltage scheduling algorithm is ...

  1. Simple buck/boost voltage regulator

    Science.gov (United States)

    Paulkovich, J.; Rodriguez, G. E.

    1980-01-01

    Circuit corrects low or high supply voltage, produces regulated output voltage. Circuit has fewer components because inductory/transformer combination and pulse-width modulator serve double duty. Regulator handles input voltage variation from as low as one half output voltage to as high as input transistor rating. Solar arrays, fuel cells, and thermionic generators might use this regulator.

  2. 30 CFR 18.47 - Voltage limitation.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Voltage limitation. 18.47 Section 18.47 Mineral... § 18.47 Voltage limitation. (a) A tool or switch held in the operator's hand or supported against his... particular voltage(s) are provided in the design and construction of the equipment, its wiring,...

  3. Cavity Voltage Phase Modulation MD

    CERN Document Server

    Mastoridis, Themistoklis; Molendijk, John; Timko, Helga; CERN. Geneva. ATS Department

    2016-01-01

    The LHC RF/LLRF system is currently configured for extremely stable RF voltage to minimize transient beam loading effects. The present scheme cannot be extended beyond nominal beam current since the demanded power would exceed the peak klystron power and lead to saturation. A new scheme has therefore been proposed: for beam currents above nominal (and possibly earlier), the cavity phase modulation by the beam will not be corrected (transient beam loading), but the strong RF feedback and One-Turn Delay feedback will still be active for loop and beam stability in physics. To achieve this, the voltage set point will be adapted for each bunch. The goal of this MD was to test a new algorithm that would adjust the voltage set point to achieve the cavity phase modulation that would minimize klystron forward power.

  4. Portable High Voltage Impulse Generator

    Directory of Open Access Journals (Sweden)

    S. Gómez

    2011-07-01

    Full Text Available This paper presents a portable high voltage impulse generator which was designed and built with insulation up to 20 kV. This design was based on previous work in which simulation software for standard waves was developed. Commercial components and low-cost components were used in this work; however, these particular elements are not generally used for high voltage applications. The impulse generators used in industry and laboratories are usually expensive; they are built to withstand extra high voltage and they are big, making them impossible to transport. The proposed generator is portable, thereby allowing tests to be made on devices that cannot be moved from their location. The results obtained with the proposed impulse generator were satisfactory in terms of time and waveforms compared to other commercial impulse generators and the standard impulse wave simulator.

  5. A low voltage CMOS low drop-out voltage regulator

    Science.gov (United States)

    Bakr, Salma Ali; Abbasi, Tanvir Ahmad; Abbasi, Mohammas Suhaib; Aldessouky, Mohamed Samir; Abbasi, Mohammad Usaid

    2009-05-01

    A low voltage implementation of a CMOS Low Drop-Out voltage regulator (LDO) is presented. The requirement of low voltage devices is crucial for portable devices that require extensive computations in a low power environment. The LDO is implemented in 90nm generic CMOS technology. It generates a fixed 0.8V from a 2.5V supply which on discharging goes to 1V. The buffer stage used is unity gain configured unbuffered OpAmp with rail-to-rail swing input stage. The simulation result shows that the implemented circuit provides load regulation of 0.004%/mA and line regulation of -11.09mV/V. The LDO provides full load transient response with a settling time of 5.2μs. Further, the dropout voltage is 200mV and the quiescent current through the pass transistor (Iload=0) is 20μA. The total power consumption of this LDO (excluding bandgap reference) is only 80μW.

  6. Implementation of Dynamic Voltage Restorer for Mitigation of Voltage Sag

    Directory of Open Access Journals (Sweden)

    K.Vinod Kumar

    2013-07-01

    Full Text Available Power quality is one of major concerns in the present. It has become important, especially with the introduction of sophisticated devices, whose performance is very sensitive to the quality of power supply. The dynamic voltage restorer (DVR is one of the modern devices used in distribution systems to improve the power quality. In this paper, emergency control in distribution systems is discussed by using the proposed multifunctional DVR control strategy.Also, themultiloop controller using the Posicast and P+Resonant controllers is proposed in order to improve the transient response and eliminate the steady state error in DVR response,respectively.The proposed process is applied to some riots in load voltage effected by induction motors starting, and a three-phase short circuit fault. The three-phase short circuits, and the large induction motors are suddenly started then voltage sags areoccurred.The innovation here is that by using the Multifunctional Dynamic Voltage Restorer, improve the power quality in distribution side. Simulation results show the capability of the DVR to control the emergency conditions of the distribution systems by using MATLAB/Simulink software.

  7. The high voltage homopolar generator

    Science.gov (United States)

    Price, J. H.; Gully, J. H.; Driga, M. D.

    1986-11-01

    System and component design features of proposed high voltage homopolar generator (HVHPG) are described. The system is to have an open circuit voltage of 500 V, a peak output current of 500 kA, 3.25 MJ of stored inertial energy and possess an average magnetic-flux density of 5 T. Stator assembly components are discussed, including the stator, mount structure, hydrostatic bearings, main and motoring brushgears and rotor. Planned operational procedures such as monitoring the rotor to full speed and operation with a superconducting field coil are delineated.

  8. Resilient architecture design for voltage variation

    CERN Document Server

    Reddi, Vijay Janapa

    2013-01-01

    Shrinking feature size and diminishing supply voltage are making circuits sensitive to supply voltage fluctuations within the microprocessor, caused by normal workload activity changes. If left unattended, voltage fluctuations can lead to timing violations or even transistor lifetime issues that degrade processor robustness. Mechanisms that learn to tolerate, avoid, and eliminate voltage fluctuations based on program and microarchitectural events can help steer the processor clear of danger, thus enabling tighter voltage margins that improve performance or lower power consumption. We describe

  9. Auslander-Reiten sequences and $t$-structures on the homotopy category of an abelian category

    CERN Document Server

    Backelin, Erik

    2009-01-01

    Let $\\Cab$ be an abelian category and let $\\KC$ be the bounded homotopy category of cochain complexes in $\\Cab$. We consider a $t$-structure on $\\KC$ that maps to the standard $t$-structure on the derived category $\\DC$ under the localization functor. Let $\\A$ be the heart of the $t$-structure. In the case when $\\Cab$ has finite length we show that objects of $\\Cab$ correspond to projective objects of $\\A$ and that simple objects of $\\A$ (if they exist) are given by Auslander's and Reiten's almost split sequences in $\\Cab$.

  10. Security threats categories in healthcare information systems.

    Science.gov (United States)

    Samy, Ganthan Narayana; Ahmad, Rabiah; Ismail, Zuraini

    2010-09-01

    This article attempts to investigate the various types of threats that exist in healthcare information systems (HIS). A study has been carried out in one of the government-supported hospitals in Malaysia.The hospital has been equipped with a Total Hospital Information System (THIS). The data collected were from three different departments, namely the Information Technology Department (ITD), the Medical Record Department (MRD), and the X-Ray Department, using in-depth structured interviews. The study identified 22 types of threats according to major threat categories based on ISO/IEC 27002 (ISO 27799:2008). The results show that the most critical threat for the THIS is power failure followed by acts of human error or failure and other technological factors. This research holds significant value in terms of providing a complete taxonomy of threat categories in HIS and also an important component in the risk analysis stage.

  11. Higher categories, colimits, and the blob complex

    CERN Document Server

    Morrison, Scott; 10.1073/pnas.1018168108

    2011-01-01

    We summarize our axioms for higher categories, and describe the blob complex. Fixing an n-category C, the blob complex associates a chain complex B_*(W;C)$ to any n-manifold W. The 0-th homology of this chain complex recovers the usual topological quantum field theory invariants of W. The higher homology groups should be viewed as generalizations of Hochschild homology (indeed, when W=S^1 they coincide). The blob complex has a very natural definition in terms of homotopy colimits along decompositions of the manifold W. We outline the important properties of the blob complex, and sketch the proof of a generalization of Deligne's conjecture on Hochschild cohomology and the little discs operad to higher dimensions.

  12. Visual object recognition and category-specificity

    DEFF Research Database (Denmark)

    Gerlach, Christian

    This thesis is based on seven published papers. The majority of the papers address two topics in visual object recognition: (i) category-effects at pre-semantic stages, and (ii) the integration of visual elements into elaborate shape descriptions corresponding to whole objects or large object parts...... is a description that can be matched with structural representations of whole objects or object parts stored in visual long-term memory. The process of finding a match between the configured description and stored object representations is thought of as a race among stored object representations that compete...... in visual long-term memory. In the thesis it is described how this simple model can account for a wide range of findings on category-specificity in both patients with brain damage and normal subjects. Finally, two hypotheses regarding the neural substrates of the model's components - and how activation...

  13. Categories of definiteness in Classical Armenian

    Directory of Open Access Journals (Sweden)

    Angelika Müth

    2011-08-01

    Full Text Available In this paper, the use of the definite article in semantic and pragmatic categories in the Greek and Classical Armenian New Testament translation is compared. Greek and Classical Armenian agree in their use of the definite article only in NPs determined by contrastive attributes. In all other categories the systems of both languages differ. Generally, Armenian avoids the definite article with proper nouns and nouns with unique reference, while definite articles with proper names in Greek are common (with the exception of sacred or especially “respected” persons such as prophets. If the definite article is present in Greek, it is often motivated by pragmatic factors (e.g. re-topicalization, etc.. There is no clear evidence in Armenian for the use of the definite article as a marker of generic reference, nor for the use in NPs determined by superlative, comparative or ordinal attributes.

  14. Health effects of risk-assessment categories

    Energy Technology Data Exchange (ETDEWEB)

    Kramer, C.F.; Rybicka, K.; Knutson, A.; Morris, S.C.

    1983-10-01

    Environmental and occupational health effects associated with exposures to various chemicals are a subject of increasing concern. One recently developed methodology for assessing the health impacts of various chemical compounds involves the classification of similar chemicals into risk-assessment categories (RACs). This report reviews documented human health effects for a broad range of pollutants, classified by RACs. It complements other studies that have estimated human health effects by RAC based on analysis and extrapolation of data from animal research.

  15. 7 CFR 993.515 - Size categories.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Size categories. 993.515 Section 993.515 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... system per 500 grams: 15/20, 15/22, 18/24, 20/30, 25/35, 30/40, 35/45, 40/50, 50/60, 60/70, 70/80,...

  16. Reliability Indicators of Urban Electric Network Schemes for Supply of Second and Third Category Consumers

    Directory of Open Access Journals (Sweden)

    M. Korotkevich

    2012-01-01

    Full Text Available The paper considers two schemes of the urban distributive electric network for supply of the second and third category consumers for whom indicators of reliability have been determined.As for a network scheme of the 2nd category it has been determined that while installing low-oil and vacuum switches at a distributive point the most remote transformer substation has the highest non-availability  factor which is higher of the corresponding non-availability  factor of the nearest transformer substation by 1,21–1,23 fold  accordingly.As for a network scheme of the 3rd category consumers it has been obtained the data that reliability of consumers receiving supply from bus-bars of transformer substations with 0,38 kW voltage changes  significantly (by 1,2–1,9-fold while changing a breakpoint of the network with 10 kW voltage.

  17. AN APPROACH TO ZERO CATEGORIES IN SYNTAX

    Directory of Open Access Journals (Sweden)

    Olga Vladimirovna Tikhanova

    2015-01-01

    Full Text Available The paper examined one of the least explored issues of the Russian philology, namely a syntactic zero. One should accurately differentiate the syntactic zero from other positions being not substituted in the sentence, such as ellipse, incompleteness, etc. Actually, one could hardly find the papers having considered this issue, with proper description and comprehensive differentiation for syntactic zero’ instances. Experts carried multiple debates on what one should recognize for a zero, and nobody arranged zero instances into classification. The authors made a review of the papers of academic significance the linguists have produced, and specified zero categories for the Russian language, and have sorted out the main features typical of the syntactic zero. The authors assumed that the experts could sort out much more null syntactic categories, for example, in considering the null subject in the so-called single-constituent clauses (indefinite personal or generalized personal clauses, or impersonal ones. The authors tried, in order to escape overburdening of the presentation, to start with looking into the most fundamental and universally recognized zeros, in their opinion, namely a zero form of the copula and a zero of any verb of existence. The main principle of differentiating a syntactic zero means it being isomorphic to zero categories at other levels of language, because at any level of language the concept of zero is derived by tradition upon the set of elements drawn up in compliance with the principle of oppositions (i.e. paradigm.

  18. Listeners retune phoneme categories across languages.

    Science.gov (United States)

    Reinisch, Eva; Weber, Andrea; Mitterer, Holger

    2013-02-01

    Native listeners adapt to noncanonically produced speech by retuning phoneme boundaries by means of lexical knowledge. We asked whether a second language lexicon can also guide category retuning and whether perceptual learning transfers from a second language (L2) to the native language (L1). During a Dutch lexical-decision task, German and Dutch listeners were exposed to unusual pronunciation variants in which word-final /f/ or /s/ was replaced by an ambiguous sound. At test, listeners categorized Dutch minimal word pairs ending in sounds along an /f/-/s/ continuum. Dutch L1 and German L2 listeners showed boundary shifts of a similar magnitude. Moreover, following exposure to Dutch-accented English, Dutch listeners also showed comparable effects of category retuning when they heard the same speaker speak her native language (Dutch) during the test. The former result suggests that lexical representations in a second language are specific enough to support lexically guided retuning, and the latter implies that production patterns in a second language are deemed a stable speaker characteristic likely to transfer to the native language; thus retuning of phoneme categories applies across languages.

  19. Using BIRADS categories in ROC experiments

    Science.gov (United States)

    Kallergi, Maria; Hersh, Marla R.; Thomas, Jerry A.

    2002-04-01

    This paper investigated the use of the Breast Imaging Reporting And Data System (BIRADS) Lexicon in ROC mammography experiments. Analysis was based on data from parallel ROC experiments performed at two Institutions with different readers and databases to compare film to digitized mammography. Seven readers participated in the studies and read approximately 200 cases each in two formats: film and digital or softcopy. Reporting was done using BIRADS categories 1 through 5. Training was done with a separate set of cases and included detailed review of the relationship between BIRADS and a standard ROC discrete 5-point rating scale. The results from both sites showed equivalency between film and softcopy mammography. Decisions using the BIRADS categories showed no unsampled ROC regions and no degenerate data. Fits yielded smooth ROC curves that correlated to clinical practice. In a qualitative evaluation, all observers indicated preference in using the BIRADS classes instead of a discrete or continuous rating scheme. Familiarity with the rating process seems to relieve some of the bias associated with the interpretation of digitized mammograms from computer monitors (softcopy reading). Our results suggested that BIRADS categories can be used in comparative ROC studies because they represent a scale familiar to the reader that can be followed consistently and they provide a rating approach that accounts for both positive and negative cases to be evaluated and categorized.

  20. Metacognitive control of categorial neurobehavioral decision systems

    Directory of Open Access Journals (Sweden)

    Gordon Robert Foxall

    2016-02-01

    Full Text Available The competing neuro-behavioral decision systems (CNDS model proposes that the degree to which an individual discounts the future is a function of the relative hyperactivity of an impulsive system based on the limbic and paralimbic brain regions and the relative hypoactivity of an executive system based in prefrontal cortex (PFC. The model depicts the relationship between these categorial systems in terms of the antipodal neurophysiological, behavioral, and decision (cognitive functions that engender classes normal and addictive responding. However, a case may be made for construing several components of the impulsive and executive systems depicted in the model as categories (elements of additional systems that are concerned with the metacognitive control of behavior. Hence, this paper proposes a category-based structure for understanding the effects on behavior of CNDS, which includes not only the impulsive and executive systems of the basic model but, a superordinate level of reflective or rational decision-making. Following recent developments in the modeling of cognitive control which contrasts Type 1 (rapid, autonomous, parallel processing with Type 2 (slower, computationally-demanding, sequential processing, the proposed model incorporates an arena in which the potentially conflicting imperatives of impulsive and executive systems are examined and from which a more appropriate behavioral response than impulsive choice emerges. This configuration suggests a forum in which the interaction of picoeconomic interests, which provide a cognitive dimension for CNDS, can be conceptualized. This proposition is examined in light of the resolution of conflict by means of bundling.

  1. Metacognitive Control of Categorial Neurobehavioral Decision Systems.

    Science.gov (United States)

    Foxall, Gordon R

    2016-01-01

    The competing neuro-behavioral decision systems (CNDS) model proposes that the degree to which an individual discounts the future is a function of the relative hyperactivity of an impulsive system based on the limbic and paralimbic brain regions and the relative hypoactivity of an executive system based in prefrontal cortex (PFC). The model depicts the relationship between these categorial systems in terms of the antipodal neurophysiological, behavioral, and decision (cognitive) functions that engender normal and addictive responding. However, a case may be made for construing several components of the impulsive and executive systems depicted in the model as categories (elements) of additional systems that are concerned with the metacognitive control of behavior. Hence, this paper proposes a category-based structure for understanding the effects on behavior of CNDS, which includes not only the impulsive and executive systems of the basic model but a superordinate level of reflective or rational decision-making. Following recent developments in the modeling of cognitive control which contrasts Type 1 (rapid, autonomous, parallel) processing with Type 2 (slower, computationally demanding, sequential) processing, the proposed model incorporates an arena in which the potentially conflicting imperatives of impulsive and executive systems are examined and from which a more appropriate behavioral response than impulsive choice emerges. This configuration suggests a forum in which the interaction of picoeconomic interests, which provide a cognitive dimension for CNDS, can be conceptualized. This proposition is examined in light of the resolution of conflict by means of bundling.

  2. Cross-category demand effects of price promotions.

    Science.gov (United States)

    Leeflang, Peter S H; Parreño-Selva, Josefa

    Do promotions in a certain category lead to higher revenues in other categories? If so, to what degree? The answers to these questions are highly relevant for retailers that supply products in different categories. Empirical findings in studies that consider a limited number of categories indicate small promotional cross-category effects. This study develops a framework to determine the impact of price promotions on category revenues that include interdependencies among a substantial number of categories at the category demand level. The own- and cross-category demand effects are moderated by variables such as promotion intensity, category characteristics (own-category effects), and spatial distances between shelf locations (cross-category effects). The empirical results based on daily store-level scanner data show that approximately half of all price promotions expand own-category revenues, especially for categories with deeper supported discounts. There is a high probability (61%) that a price promotion affects sales of at least one other category. The number of categories affected is not greater than two. Moderate evidence supports the existence of cross-promotional effects between categories more closely located in a store.

  3. VOLTAGE REGULATORS OF SYNCHRONOUS GENERATORS

    Directory of Open Access Journals (Sweden)

    Grigorash O. V.

    2015-06-01

    Full Text Available Synchronous generators are the primary source of electrical power autonomous electrosupply systems, including backup systems. They are also used in a structure of rotating electricity converters and are widely used in renewable energy as part of wind power plants of small, mini and micro hydroelectric plants. Increasing the speed and the accuracy of the system of the voltage regulation of synchronous generators is possible due to the development of combined systems containing more stabilizers. The article illustrates the functional schemes of circuit voltage stabilizers and frequency synchronous generators (with electromagnetic excitation and permanent magnet excitation and describes the features of their work, including two and three-aggregate rotating converters of electricity used in uninterruptible power supply systems. To improve the technical characteristics of the system of stabilization we have proposed functional solutions for stabilizers of synchronous generators made on the base of direct frequency converters and using a transformer with a rotating magnetic field. To improve the reliability of and to improve the operational characteristics of the autonomous independent sources of electricity we suggest creating the main functional blocks and the elements of the stabilization system in a modular way. The functional circuit solutions of voltage regulators of synchronous generators and the characteristics of their work considered in the article, are able to improve the efficiency of pre-design work in the development of new technical solutions for stabilizing the voltage and the frequency in synchronous generators of electrosupply autonomous systems

  4. Frequency-controlled voltage regulator

    Science.gov (United States)

    Mclyman, W. T.

    1980-01-01

    Converting input ac to higher frequency reduce size and weight and makes possible unique kind of regulation. Since conversion frequency is above range of human hearing, supply generated on audible noise. It also exploits highfrequency conversion features to regulate its output voltage in novel way. Circuit is inherently short-circuit proof.

  5. Graded mutation in cluster categories coming from hereditary categories with a tilting object

    CERN Document Server

    Bertani-Økland, Marco Angel; Wrålsen, Anette

    2010-01-01

    We present a graded mutation rule for quivers of cluster-tilted algebras. Furthermore, we give a technique to recover a cluster-tilting object from its graded quiver in the cluster category of coh $\\mathbb{X}$.

  6. 5 CFR 294.103 - Definitions of categories and assignment of requests and requesters to categories.

    Science.gov (United States)

    2010-01-01

    ... properly belongs in this category, OPM will look first to the intended use of the documents being requested... journalists may be regarded as representatives of the news media if they demonstrate a solid basis...

  7. Voltage-gated Proton Channels

    Science.gov (United States)

    DeCoursey, Thomas E.

    2014-01-01

    Voltage-gated proton channels, HV1, have vaulted from the realm of the esoteric into the forefront of a central question facing ion channel biophysicists, namely the mechanism by which voltage-dependent gating occurs. This transformation is the result of several factors. Identification of the gene in 2006 revealed that proton channels are homologues of the voltage-sensing domain of most other voltage-gated ion channels. Unique, or at least eccentric, properties of proton channels include dimeric architecture with dual conduction pathways, perfect proton selectivity, a single-channel conductance ~103 smaller than most ion channels, voltage-dependent gating that is strongly modulated by the pH gradient, ΔpH, and potent inhibition by Zn2+ (in many species) but an absence of other potent inhibitors. The recent identification of HV1 in three unicellular marine plankton species has dramatically expanded the phylogenetic family tree. Interest in proton channels in their own right has increased as important physiological roles have been identified in many cells. Proton channels trigger the bioluminescent flash of dinoflagellates, facilitate calcification by coccolithophores, regulate pH-dependent processes in eggs and sperm during fertilization, secrete acid to control the pH of airway fluids, facilitate histamine secretion by basophils, and play a signaling role in facilitating B-cell receptor mediated responses in B lymphocytes. The most elaborate and best-established functions occur in phagocytes, where proton channels optimize the activity of NADPH oxidase, an important producer of reactive oxygen species. Proton efflux mediated by HV1 balances the charge translocated across the membrane by electrons through NADPH oxidase, minimizes changes in cytoplasmic and phagosomal pH, limits osmotic swelling of the phagosome, and provides substrate H+ for the production of H2O2 and HOCl, reactive oxygen species crucial to killing pathogens. PMID:23798303

  8. From groups to categorial algebra introduction to protomodular and mal’tsev categories

    CERN Document Server

    Bourn, Dominique

    2017-01-01

    This book gives a thorough and entirely self-contained, in-depth introduction to a specific approach to group theory, in a large sense of that word. The focus lie on the relationships which a group may have with other groups, via “universal properties”, a view on that group “from the outside”. This method of categorical algebra, is actually not limited to the study of groups alone, but applies equally well to other similar categories of algebraic objects. By introducing protomodular categories and Mal’tsev categories, which form a larger class, the structural properties of the category Gp of groups, show how they emerge from four very basic observations about the algebraic litteral calculus and how, studied for themselves at the conceptual categorical level, they lead to the main striking features of the category Gp of groups. Hardly any previous knowledge of category theory is assumed, and just a little experience with standard algebraic structures such as groups and monoids. Examples and exercises...

  9. Cross-category demand effects of price promotions

    NARCIS (Netherlands)

    Leeflang, Peter S. H.; Parreno-Selva, Josefa

    2012-01-01

    Do promotions in a certain category lead to higher revenues in other categories? If so, to what degree? The answers to these questions are highly relevant for retailers that supply products in different categories. Empirical findings in studies that consider a limited number of categories indicate s

  10. Formation of category representations in superior temporal sulcus

    NARCIS (Netherlands)

    Linden, M. Van der; Turennout, M. van; Indefrey, P.

    2010-01-01

    The human brain contains cortical areas specialized in representing object categories. Visual experience is known to change the responses in these category-selective areas of the brain. However, little is known about how category training specifically affects cortical category selectivity. Here, we

  11. When is category specific in Alzheimer's disease?

    Science.gov (United States)

    Laws, Keith R; Gale, Tim M; Leeson, Verity C; Crawford, John R

    2005-08-01

    Mixed findings have emerged concerning whether category-specific disorders occur in Alzheimer's disease. Factors that may contribute to these inconsistencies include: ceiling effects/skewed distributions for control data in some studies; differences in the severity of cognitive deficit in patients; and differences in the type of analysis (in particular, if and how controls are used to analyse single case data). We examined picture naming in Alzheimer's patients and matched elderly healthy normal controls in three experiments. These experiments used stimuli that did and did not produce ceiling effects/skewed data in controls. In Experiment 1, we examined for category effects in individual DAT patients using commonly used analyses for single cases (chi2 and z-scores). The different techniques produced quite different outcomes. In Experiment 2a, we used the same techniques on a different group of patients with similar outcomes. Finally, in Experiment 2b, we examined the same patients but (a) used stimuli that did not produce ceiling effects/skewed distributions in healthy controls, and (b) used statistical methods that did not treat the control sample as a population. We found that ceiling effects in controls may markedly inflate the incidence of dissociations in which living things are differentially impaired and seriously underestimate dissociations in the opposite direction. In addition, methods that treat the control sample as a population led to inflation in the overall number of dissociations detected. These findings have implications for the reliability of category effects previously reported both in Alzheimer patients and in other pathologies. In particular, they suggest that the greater proportion of living than nonliving deficits reported in the literature may be an artifact of the methods used.

  12. Ambiguity produces attention shifts in category learning.

    Science.gov (United States)

    Vadillo, Miguel A; Orgaz, Cristina; Luque, David; Nelson, James Byron

    2016-04-01

    It has been suggested that people and nonhuman animals protect their knowledge from interference by shifting attention toward the context when presented with information that contradicts their previous beliefs. Despite that suggestion, no studies have directly measured changes in attention while participants are exposed to an interference treatment. In the present experiments, we adapted a dot-probe task to track participants' attention to cues and contexts while they were completing a simple category learning task. The results support the hypothesis that interference produces a change in the allocation of attention to cues and contexts.

  13. Introduction to Categories and Categorical Logic

    Science.gov (United States)

    Abramsky, S.; Tzevelekos, N.

    The aim of these notes is to provide a succinct, accessible introduction to some of the basic ideas of category theory and categorical logic. The notes are based on a lecture course given at Oxford over the past few years. They contain numerous exercises, and hopefully will prove useful for self-study by those seeking a first introduction to the subject, with fairly minimal prerequisites. The coverage is by no means comprehensive, but should provide a good basis for further study; a guide to further reading is included.

  14. Topoi the categorial analysis of logic

    CERN Document Server

    Goldblatt, R

    1984-01-01

    The first of its kind, this book presents a widely accessible exposition of topos theory, aimed at the philosopher-logician as well as the mathematician. It is suitable for individual study or use in class at the graduate level (it includes 500 exercises). It begins with a fully motivated introduction to category theory itself, moving always from the particular example to the abstract concept. It then introduces the notion of elementary topos, with a wide range of examples and goes on to develop its theory in depth, and to elicit in detail its relationship to Kripke's intuitionistic semantics,

  15. Over-voltage protection system and method

    Energy Technology Data Exchange (ETDEWEB)

    Chi, Song; Dong, Dong; Lai, Rixin

    2017-05-02

    An over-voltage protection system includes an electronic valve connected across two terminals of a circuit and an over-voltage detection circuit connected across one of the plurality of semiconductor devices for detecting an over-voltage across the circuit. The electronic valve includes a plurality of semiconductor devices connected in series. The over-voltage detection circuit includes a voltage divider circuit connected to a break-over diode in a way to provide a representative low voltage to the break-over diode and an optocoupler configured to receive a current from the break-over diode when the representative low voltage exceeds a threshold voltage of the break-over diode indicating an over-voltage condition. The representative low voltage provided to the break-over diode represents a voltage across the one semiconductor device. A plurality of self-powered gate drive circuits are connected to the plurality of semiconductor devices, wherein the plurality of self-powered gate drive circuits receive over-voltage triggering pulses from the optocoupler during the over-voltage condition and switch on the plurality of semiconductor devices to bypass the circuit.

  16. Advances in high voltage engineering

    CERN Document Server

    Haddad, A

    2005-01-01

    This book addresses the very latest research and development issues in high voltage technology and is intended as a reference source for researchers and students in the field, specifically covering developments throughout the past decade. This unique blend of expert authors and comprehensive subject coverage means that this book is ideally suited as a reference source for engineers and academics in the field for years to come.

  17. High Voltage Pulse Testing Survey.

    Science.gov (United States)

    1985-10-01

    Cryogenic 23 E. Liquids 26 F. Solids 28 1. Polyethylene 28 2. Cross-Linked Polyethylene ( XLPE ) 29 3. Polyimide and Polyvenylchloride (PVC) 31 VI Benefits 35 A...Strength of XLPE Cables 29 vii * 4" I PROGRAM OBJECTIVES The Pulse Test Survey summarizes government, industry, and technical reports on high voltage pulse...system of silicone oil on a XLPE (cross-linked polyethylene) spacer tends to lower the impulse breakdown by approximately 10 percent. The negative impulse

  18. TRANSISTOR HIGH VOLTAGE POWER SUPPLY

    Science.gov (United States)

    Driver, G.E.

    1958-07-15

    High voltage, direct current power supplies are described for use with battery powered nuclear detection equipment. The particular advantages of the power supply described, are increased efficiency and reduced size and welght brought about by the use of transistors in the circuit. An important feature resides tn the employment of a pair of transistors in an alternatefiring oscillator circuit having a coupling transformer and other circuit components which are used for interconnecting the various electrodes of the transistors.

  19. The Graph Isomorphism Problem and approximate categories

    CERN Document Server

    Derksen, Harm

    2010-01-01

    It is unknown whether two graphs can be tested for isomorphism in polynomial time. A classical approach to the Graph Isomorphism Problem is the d-dimensional Weisfeiler-Lehman algorithm. The d-dimensional WL-algorithm can distinguish many pairs of graphs, but the pairs of non-isomorphic graphs constructed by Cai, Furer and Immerman it cannot distinguish. If d is fixed, then the WL-algorithm runs in polynomial time. We will formulate the Graph Isomorphism Problem as an Orbit Problem: Given a representation V of an algebraic group G and two elements v_1,v_2 in V, decide whether v_1 and v_2 lie in the same G-orbit. Then we attack the Orbit Problem by constructing certain approximate categories C_d(V), d=1,2,3,... whose objects include the elements of V. We show that v_1 and v_2 are not in the same orbit by showing that they are not isomorphic in the category C_d(V) for some d. For every d this gives us an algorithm for isomorphism testing. We will show that the WL-algorithms reduce to our algorithms, but that ou...

  20. Antisocial behavior: Dimension or category(ies?

    Directory of Open Access Journals (Sweden)

    Biro Mikloš

    2008-01-01

    Full Text Available Classificatory systems (DSM-IV, ICD-10 use different criteria for defining a rather common antisocial disorder, traditionally referred as psychopathy. Most empirical studies of this phenomenon use Cleckley's operational definition that was applied and amended in Hare's revised Psychopathy Checklist (PCL-R. In modern literature, the fact that there is less than a perfect correspondence between classificatory systems and Hare's PCL-R is often cited as an indication that antisocial behavior is not confined to a distinct category of people but is rather a continuous personality dimension. In order to further elucidate the nosology of antisocial behaviors, a Psychopathy Assessment Questionnaire (PAQ based on Cleckley - Hare's criteria and consisting of 40 binary items was administered to 339 men (135 prisoners and 204 members of the general population. Four distinct clusters of respondents were identified by means of hierarchical cluster analysis: Psychopathic type (characterized by high positive scores on dimension of Unemotionality; Antisocial type (characterized by high positive scores on Social deviance dimension; Adapted type (characterized by negative scores on all dimensions; and Hyper-controlled type (characterized by extremely negative scores on dimension Social deviance accompanied with positive scores on Unemotionality dimension. Additional comparison with MMPI profiles which classified prison sample in two groups ("Psychopathic profiles" and "Non- Psychopathic profiles" shows that there is no expected compatibility between MMPI and PAQ. We conclude that Antisocial type can be treated as a distinct category, while Psychopathic type displays characteristics of dimensional distribution.

  1. CEUS Helps to Rerate Small Breast Tumors of BI-RADS Category 3 and Category 4

    Directory of Open Access Journals (Sweden)

    Jian-xing Zhang

    2014-01-01

    Full Text Available Purpose. The primary aim of this study was to explore if classification, whether using the BI-RADS categories based on CEUS or conventional ultrasound, was conducive to the identification of benign and malignant category 3 or 4 small breast lesions. Material and Methods. We evaluated 30 malignant and 77 benign small breast lesions using CEUS. The range of enhancement, type of enhancement strength, intensity of enhancement, and enhancement patterns were independent factors included to assess the BI-RADS categories. Results. Of the nonenhanced breast lesions, 97.8% (44/45 were malignant, while, of the hyperplasic nodules, 96.8% (30/31 showed no enhancement in our study. Category changes of the lesions were made according to the features determined using CEUS. The results showed that these features could improve diagnostic sensitivity (from 70.0 to 80.0, 80.0, 90.0, and 90.0%, reduce the negative likelihood ratio (from 0.33 to 0.22, 0.25, 0.11, and 0.12, and improve the NPV (from 88.8 to 92.2, 91.2, 96.2, and 95.5%. However, this was not conducive to improve diagnostic specificity or the PPV. Conclusion. The vast majority of nonenhanced small breast lesions were malignant and most of the hyperplasic nodules showed no contrast enhancement. As a reference, CEUS was helpful in identifying BI-RADS category 3 or 4 small breast lesions.

  2. Low voltage electron beam accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Ochi, Masafumi [Iwasaki Electric Co., Ltd., Tokyo (Japan)

    2003-02-01

    Widely used electron accelerators in industries are the electron beams with acceleration voltage at 300 kV or less. The typical examples are shown on manufactures in Japan, equipment configuration, operation, determination of process parameters, and basic maintenance requirement of the electron beam processors. New electron beam processors with acceleration voltage around 100 kV were introduced maintaining the relatively high dose speed capability of around 10,000 kGy x mpm at production by ESI (Energy Science Inc. USA, Iwasaki Electric Group). The application field like printing and coating for packaging requires treating thickness of 30 micron or less. It does not require high voltage over 110 kV. Also recently developed is a miniature bulb type electron beam tube with energy less than 60 kV. The new application area for this new electron beam tube is being searched. The drive force of this technology to spread in the industries would be further development of new application, process and market as well as the price reduction of the equipment, upon which further acknowledgement and acceptance of the technology to societies and industries would entirely depend. (Y. Tanaka)

  3. Measurable versions of the LS category on laminations

    CERN Document Server

    Meniño, Carlos

    2011-01-01

    We give two new versions of the LS category for the set-up of measurable laminations defined by Berm\\'udez. Both of these versions must be considered as "tangential categories". The first one, simply called (LS) category, is the direct analogue for measurable laminations of the tangential category of (topological) laminations introduced by Colman Vale and Mac\\'ias Virg\\'os. For the measurable lamination that underlies any lamination, our measurable tangential category is a lower bound of the tangential category. The second version, called the measured category, depends on the choice of a transverse invariant measure. We show that both of these "tangential categories" satisfy appropriate versions of some well known properties of the classical category: the homotopy invariance, a dimensional upper bound, a cohomological lower bound (cup length), and an upper bound given by the critical points of a smooth function.

  4. On Monoids in the Category of Sets and Relations

    Science.gov (United States)

    Jenčová, Anna; Jenča, Gejza

    2017-02-01

    The category R e l is the category of sets (objects) and relations (morphisms). Equipped with the direct product of sets, R e l is a monoidal category. Moreover, R e l is a locally posetal 2-category, since every homset R e l(A,B) is a poset with respect to inclusion. We examine the 2-category of monoids R e l M o n in this category. The morphism we use are lax. This category includes, as subcategories, various interesting classes: hypergroups, partial monoids (which include various types of quantum logics, for example effect algebras) and small categories. We show how the 2-categorical structure gives rise to several previously defined notions in these categories, for example certain types of congruence relations on generalized effect algebras. This explains where these definitions come from.

  5. Piezo Voltage Controlled Planar Hall Effect Devices

    OpenAIRE

    Bao Zhang; Kang-Kang Meng; Mei-Yin Yang; Edmonds, K. W.; Hao Zhang; Kai-Ming Cai; Yu Sheng; Nan Zhang; Yang Ji; Jian-Hua Zhao; Hou-Zhi Zheng; Kai-You Wang

    2015-01-01

    The electrical control of the magnetization switching in ferromagnets is highly desired for future spintronic applications. Here we report on hybrid piezoelectric (PZT)/ferromagnetic (Co2FeAl) devices in which the planar Hall voltage in the ferromagnetic layer is tuned solely by piezo voltages. The change of planar Hall voltage is associated with magnetization switching through 90° in the plane under piezo voltages. Room temperature magnetic NOT and NOR gates are demonstrated based on the pie...

  6. Outward Rectification of Voltage-Gated K+ Channels Evolved at Least Twice in Life History.

    Science.gov (United States)

    Riedelsberger, Janin; Dreyer, Ingo; Gonzalez, Wendy

    2015-01-01

    Voltage-gated potassium (K+) channels are present in all living systems. Despite high structural similarities in the transmembrane domains (TMD), this K+ channel type segregates into at least two main functional categories-hyperpolarization-activated, inward-rectifying (Kin) and depolarization-activated, outward-rectifying (Kout) channels. Voltage-gated K+ channels sense the membrane voltage via a voltage-sensing domain that is connected to the conduction pathway of the channel. It has been shown that the voltage-sensing mechanism is the same in Kin and Kout channels, but its performance results in opposite pore conformations. It is not known how the different coupling of voltage-sensor and pore is implemented. Here, we studied sequence and structural data of voltage-gated K+ channels from animals and plants with emphasis on the property of opposite rectification. We identified structural hotspots that alone allow already the distinction between Kin and Kout channels. Among them is a loop between TMD S5 and the pore that is very short in animal Kout, longer in plant and animal Kin and the longest in plant Kout channels. In combination with further structural and phylogenetic analyses this finding suggests that outward-rectification evolved twice and independently in the animal and plant kingdom.

  7. PMU-Aided Voltage Security Assessment for a Wind Power Plant: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, H.; Zhang, Y. C.; Zhang, J. J.; Muljadi, E.

    2015-04-08

    Because wind power penetration levels in electric power systems are continuously increasing, voltage stability is a critical issue for maintaining power system security and operation. The traditional methods to analyze voltage stability can be classified into two categories: dynamic and steady-state. Dynamic analysis relies on time-domain simulations of faults at different locations; however, this method needs to exhaust faults at all locations to find the security region for voltage at a single bus. With the widely located phasor measurement units (PMUs), the Thevenin equivalent matrix can be calculated by the voltage and current information collected by the PMUs. This paper proposes a method based on a Thevenin equivalent matrix to identify system locations that will have the greatest impact on the voltage at the wind power plant’s point of interconnection. The number of dynamic voltage stability analysis runs is greatly reduced by using the proposed method. The numerical results demonstrate the feasibility, effectiveness, and robustness of the proposed approach for voltage security assessment for a wind power plant.

  8. PMU-Aided Voltage Security Assessment for a Wind Power Plant

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, Huaiguang; Zhang, Yingchen; Zhang, Jun Jason; Muljadi, Eduard

    2015-10-05

    Because wind power penetration levels in electric power systems are continuously increasing, voltage stability is a critical issue for maintaining power system security and operation. The traditional methods to analyze voltage stability can be classified into two categories: dynamic and steady-state. Dynamic analysis relies on time-domain simulations of faults at different locations; however, this method needs to exhaust faults at all locations to find the security region for voltage at a single bus. With the widely located phasor measurement units (PMUs), the Thevenin equivalent matrix can be calculated by the voltage and current information collected by the PMUs. This paper proposes a method based on a Thevenin equivalent matrix to identify system locations that will have the greatest impact on the voltage at the wind power plant's point of interconnection. The number of dynamic voltage stability analysis runs is greatly reduced by using the proposed method. The numerical results demonstrate the feasibility, effectiveness, and robustness of the proposed approach for voltage security assessment for a wind power plant.

  9. 49 CFR 234.221 - Lamp voltage.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Lamp voltage. 234.221 Section 234.221 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION..., Inspection, and Testing Maintenance Standards § 234.221 Lamp voltage. The voltage at each lamp shall...

  10. Bootstrapped Low-Voltage Analog Switches

    DEFF Research Database (Denmark)

    Steensgaard-Madsen, Jesper

    1999-01-01

    Novel low-voltage constant-impedance analog switch circuits are proposed. The switch element is a single MOSFET, and constant-impedance operation is obtained using simple circuits to adjust the gate and bulk voltages relative to the switched signal. Low-voltage (1-volt) operation is made feasible...

  11. Investigating cross-category brand loyalty behavior in FMCG

    DEFF Research Database (Denmark)

    Boztug, Yasemin; Hildebrandt, Lutz; Silberhorn, Nadja

    In competitive markets, customer retention is more efficient than trying to attract new customers. Brand loyalty is an intrinsic commitment to repeatedly purchase a particular brand. But most analyses have been conducted in one specific category only. It has been shown that product purchases in one...... category depend on purchases in other categories. The aspect of cross-category related brand loyalty has been somewhat neglected so far. We concentrate on cross-category relationships of strong national brands and on how customers' brand choice decisions are related across several product categories....

  12. Quasi-coherent Hecke category and Demazure descent

    DEFF Research Database (Denmark)

    Arkhipov, Sergey; Kanstrup, Tina

    2015-01-01

    Let G be a reductive algebraic group with a Borel subgroup B. We define the quasi-coherent Hecke category for the pair (G,B). For any regular Noetherian G- scheme X we construct a monoidal action of the Hecke category on the derived category of B-equivariant quasi-coherent sheaves on X. Using...... the action we define the Demazure Descent Data on the latter category and prove that the Descent category is equivalent to the derived category of G-equivariant sheaves on X....

  13. Accuracy of the mammographic report category according to BIRADS.

    Science.gov (United States)

    Hirunpat, Siriporn; Tanomkiat, Wiwatana; Khojarern, Rungrat; Arpakupakul, Nualta

    2005-01-01

    To determine the accuracy and predictive value of the mammographic report according to the BIRADS categories in Songklanagarind University Hospital. Mammograms of 1000 women who came to Songklanagarind University Hospital from June 1998 to September 1999 were reported and placed in category 1 for negative results, category 2 for benign lesions, category 3 for probably benign lesions, category 4 for suspicious lesions and category 5 for highly suspicious lesions. Accuracy was determined by either histology or by unchanged follow-up mammography within 24 months. The total accuracy was 97.8%, sensitivity 62.5% and specificity 98.1%.

  14. Category of diversity in linguaphilosophic prospect

    Directory of Open Access Journals (Sweden)

    Kulpina Valentina Grigorievna

    2016-06-01

    Full Text Available Category of diversity is described in subcategories of homogeneous and inhomogeneous multitudes, allowing to reveal a natural categorization within the category of quantity. An integral multitude, presented within the category of quantity, is formed, among other things of countable nouns, like: штуки, головы, кочаны, etc.: булочек четыре штуки, сорок голов скота, два кочана капусты. When account is carried out on the basis of countable nouns (explicable or implied, a man is abstracted from the individual characteristics of objects, they are thought of as the same person and attention to their differences is not focused on. It is described a type of homogeneous multitudes as the “group” refer to the number of the type стадо etc.: стадо овец, косяк рыб, лежбище тюленейстадо и др.: стадо овец, косяк рыб, лежбище тюленей. It is established cross-language differences filling lexical units within the multitude uniform on the basis of a comparison of the Russian and Polish languages. The focus of the article is the heterogeneity of the multitude category, designated as a complementary multitude, in which the union objects to the group is based on the complementary elements provided in various multitudes, multitudes with different nominations and acting in conjunction with the names of the objects themselves, which form these multitudes: ассорти, коллекция, канцтовары. The essence of such multitudes is that elements within the group combined a certain connection (as opposed to a uniform multitude, are not the same, but different and complementary. It is nalyzed different groups of such multitudes in the household, business, the scientific field, in onomastics. Among the non-uniform multitudes, groups of people, for example, are viewed on the material of the Polish and German groups

  15. Introduction to Categories and Categorical Logic

    CERN Document Server

    Abramsky, Samson

    2011-01-01

    The aim of these notes is to provide a succinct, accessible introduction to some of the basic ideas of category theory and categorical logic. The notes are based on a lecture course given at Oxford over the past few years. They contain numerous exercises, and hopefully will prove useful for self-study by those seeking a first introduction to the subject, with fairly minimal prerequisites. The coverage is by no means comprehensive, but should provide a good basis for further study; a guide to further reading is included. The main prerequisite is a basic familiarity with the elements of discrete mathematics: sets, relations and functions. An Appendix contains a summary of what we will need, and it may be useful to review this first. In addition, some prior exposure to abstract algebra - vector spaces and linear maps, or groups and group homomorphisms - would be helpful.

  16. Housekeeping category corrective action unit work plan

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-08-01

    The purpose of this Corrective Action Unit (CAU) Work Plan is to provide a strategy to be used by the US Department of Energy Nevada Operations Office (DOE/NV), the US Department of Defense (DoD) Defense Special Weapons Agency (DSWA) (formerly the Defense Nuclear Agency), and contractor personnel for conducting corrective actions at the Nevada Test Site (NTS) and Nevada off-site locations including the Tonopah Test Range (TTR), the Project Shoal Area, and the Central Nevada Test Area. This Work Plan applies to housekeeping category CAUs already listed in the Federal Facility Agreement and Consent Order (FFACO) Appendices (FFACO, 1996) as well as newly identified Corrective Action Sites (CASs) that will follow the housekeeping process.

  17. Algebraic Theories and (Infinity,1)-Categories

    CERN Document Server

    Cranch, James

    2010-01-01

    We adapt the classical framework of algebraic theories to work in the setting of (infinity,1)-categories developed by Joyal and Lurie. This gives a suitable approach for describing highly structured objects from homotopy theory. A central example, treated at length, is the theory of E_infinity spaces: this has a tidy combinatorial description in terms of span diagrams of finite sets. We introduce a theory of distributive laws, allowing us to describe objects with two distributing E_infinity stuctures. From this we produce a theory of E_infinity ring spaces. We also study grouplike objects, and produce theories modelling infinite loop spaces (or connective spectra), and infinite loop spaces with coherent multiplicative structure (or connective ring spectra). We use this to construct the units of a grouplike E_infinity ring space in a natural manner. Lastly we provide a speculative pleasant description of the K-theory of monoidal quasicategories and quasicategories with ring-like structures.

  18. Sacrality and worldmaking: new categorial perspectives

    Directory of Open Access Journals (Sweden)

    William E. Paden

    1999-01-01

    Full Text Available The category of the sacred in particular and the role of transcultural concept-formation in general have undergone an obvious crisis. For the most part, "the sacred," if not an empty label, has been linked with theologism, and transcultural concepts have been condemned for their general non-comparability and colonialist intent. The author approaches the matter of transcultural templates through an analysis of certain concepts of sacrality. With some exceptions, the discourse of sacrality has indeed been dominated by a single model, where "the sacred" became a reified noun—a substantive term for a supernatural reality, a label for the transcendent, or even an epithet for divinity, mystery, the wholly other. As such, the expression has functioned to bestow a sense of unity to the diversity of cultures, link that unity with a transcendent reality, and offer a simple way of making sense of otherwise foreign beliefs and practices by giving them a familiar, generic referent.

  19. Modeling and Simulation of 3-Phase Voltage and Current Source Inverter using MATLAB/SIMULINK for Various Loads

    Directory of Open Access Journals (Sweden)

    Braj Kishor Verma

    2014-05-01

    Full Text Available In today’s world inverters are used to convert a single or multiple phase AC voltages from a DC supply source. Various types of inverters such as 1-phase inverters and 3-phase inverters are used for various industrial applications. Inverter comes in two categories which is voltage source inverter (VSI and current source inverter (CSI. In this paper work simulation of three phase VSI and CSI is performed using MATLAB/SIMULINK. THD is compared in voltage and current waveform and analyzed in different load conditions

  20. Voltage Management in Unbalanced Low Voltage Networks Using a Decoupled Phase-Tap-Changer Transformer

    DEFF Research Database (Denmark)

    Coppo, Massimiliano; Turri, Roberto; Marinelli, Mattia

    2014-01-01

    The paper studies a medium voltage-low voltage transformer with a decoupled on load tap changer capability on each phase. The overall objective is the evaluation of the potential benefits on a low voltage network of such possibility. A realistic Danish low voltage network is used for the analysis...

  1. Estimating Voltage Asymmetry Making by One Phase Micro-generator in Low Voltage Network

    Directory of Open Access Journals (Sweden)

    Marian Sobierajski

    2014-12-01

    Full Text Available Connection of one phase micro-generator to the low voltage network increases voltage asymmetry. The voltage asymmetry is defined as the quotient of negative and positive voltage components. The mathematical background of exact and rough computation of the asymmetry quotient is presented in the paper. Considerations are illustrated by simple examples.

  2. 76 FR 70721 - Voltage Coordination on High Voltage Grids; Notice of Staff Workshop

    Science.gov (United States)

    2011-11-15

    ... Energy Regulatory Commission Voltage Coordination on High Voltage Grids; Notice of Staff Workshop Take notice that the Federal Energy Regulatory Commission will hold a Workshop on Voltage Coordination on High Voltage Grids on Thursday, December 1, 2011 from 9 a.m. to 4:30 p.m. This staff-led workshop will be...

  3. Improving transition voltage spectroscopy of molecular junctions

    DEFF Research Database (Denmark)

    Markussen, Troels; Chen, Jingzhe; Thygesen, Kristian Sommer

    2011-01-01

    Transition voltage spectroscopy (TVS) is a promising spectroscopic tool for molecular junctions. The principles in TVS is to find the minimum on a Fowler-Nordheim plot where ln(I/V2) is plotted against 1/V and relate the voltage at the minimum Vmin to the closest molecular level. Importantly, Vmin...... is approximately half the voltage required to see a peak in the dI/dV curve. Information about the molecular level position can thus be obtained at relatively low voltages. In this work we show that the molecular level position can be determined at even lower voltages, Vmin(α), by finding the minimum of ln...

  4. Piezo Voltage Controlled Planar Hall Effect Devices

    Science.gov (United States)

    Zhang, Bao; Meng, Kang-Kang; Yang, Mei-Yin; Edmonds, K. W.; Zhang, Hao; Cai, Kai-Ming; Sheng, Yu; Zhang, Nan; Ji, Yang; Zhao, Jian-Hua; Zheng, Hou-Zhi; Wang, Kai-You

    2016-06-01

    The electrical control of the magnetization switching in ferromagnets is highly desired for future spintronic applications. Here we report on hybrid piezoelectric (PZT)/ferromagnetic (Co2FeAl) devices in which the planar Hall voltage in the ferromagnetic layer is tuned solely by piezo voltages. The change of planar Hall voltage is associated with magnetization switching through 90° in the plane under piezo voltages. Room temperature magnetic NOT and NOR gates are demonstrated based on the piezo voltage controlled Co2FeAl planar Hall effect devices without the external magnetic field. Our demonstration may lead to the realization of both information storage and processing using ferromagnetic materials.

  5. Piezo Voltage Controlled Planar Hall Effect Devices.

    Science.gov (United States)

    Zhang, Bao; Meng, Kang-Kang; Yang, Mei-Yin; Edmonds, K W; Zhang, Hao; Cai, Kai-Ming; Sheng, Yu; Zhang, Nan; Ji, Yang; Zhao, Jian-Hua; Zheng, Hou-Zhi; Wang, Kai-You

    2016-06-22

    The electrical control of the magnetization switching in ferromagnets is highly desired for future spintronic applications. Here we report on hybrid piezoelectric (PZT)/ferromagnetic (Co2FeAl) devices in which the planar Hall voltage in the ferromagnetic layer is tuned solely by piezo voltages. The change of planar Hall voltage is associated with magnetization switching through 90° in the plane under piezo voltages. Room temperature magnetic NOT and NOR gates are demonstrated based on the piezo voltage controlled Co2FeAl planar Hall effect devices without the external magnetic field. Our demonstration may lead to the realization of both information storage and processing using ferromagnetic materials.

  6. Case-like Categories in Children: The Actor and Some Related Categories

    Science.gov (United States)

    Braine, Martin D. S.; Wells, Robin S.

    1978-01-01

    Five experiments were performed in which nursery school children were taught to identify persons, animals, or objects in pictures that took the nominative, objective, or locative case in sentences about the pictures. Inferences are made about categories in children's thinking including animate, and actor and agent. (CTM)

  7. Category Specificity in Normal Episodic Learning: Applications to Object Recognition and Category-Specific Agnosia

    Science.gov (United States)

    Bukach, Cindy M.; Bub, Daniel N.; Masson, Michael E. J.; Lindsay, D. Stephen

    2004-01-01

    Studies of patients with category-specific agnosia (CSA) have given rise to multiple theories of object recognition, most of which assume the existence of a stable, abstract semantic memory system. We applied an episodic view of memory to questions raised by CSA in a series of studies examining normal observers' recall of newly learned attributes…

  8. CATEGORIES OF INFORMATION SECURITY AND CATEGORY “INFORMATION SYSTEM” IN CORPOPRATE GOVEMANCE IN CONSTRACTION INDUSTRY

    OpenAIRE

    Cherednychenko, A.

    2014-01-01

    This article analyzes the provisions of legal acts, given the definition of the conceptual apparatus of information security. Identified major categories of security in corporate governance (including construction enterprises) and provided suggestions for improving the level of protection of such information.

  9. Capacitor Voltages Measurement and Balancing in Flying Capacitor Multilevel Converters Utilizing a Single Voltage Sensor

    DEFF Research Database (Denmark)

    Farivar, Glen; Ghias, Amer M. Y. M.; Hredzak, Branislav

    2017-01-01

    This paper proposes a new method for measuring capacitor voltages in multilevel flying capacitor (FC) converters that requires only one voltage sensor per phase leg. Multiple dc voltage sensors traditionally used to measure the capacitor voltages are replaced with a single voltage sensor at the ac...... side of the phase leg. The proposed method is subsequently used to balance the capacitor voltages using only the measured ac voltage. The operation of the proposed measurement and balancing method is independent of the number of the converter levels. Experimental results presented for a five-level FC...

  10. Voltage-Sensitive Load Controllers for Voltage Regulation and Increased Load Factor in Distribution Systems

    DEFF Research Database (Denmark)

    Douglass, Philip James; Garcia-Valle, Rodrigo; Østergaard, Jacob

    2014-01-01

    consumption which can be mapped to temperature setpoint offsets of thermostat controlled loads. In networks where a lower voltage level corresponds to high system load (and vice versa), this controller acts to regulate voltage and increase the load factor. Simulations are conducted on low- and medium-voltage......This paper presents a novel controller design for controlling appliances based on local measurements of voltage. The controller finds the normalized voltage deviation accounting for the sensitivity of voltage measurements to appliance state. The controller produces a signal indicating desired power...... distribution systems with residential loads including voltage-sensitive water heaters. In low-voltage systems, the results of the simulations show the controller to be effective at reducing the extremes of voltage and increasing the load factor while respecting end-use temperature constraints. In medium-voltage...

  11. Voltage-controlled photonic oscillator.

    Science.gov (United States)

    Savchenkov, A A; Ilchenko, V S; Liang, W; Eliyahu, D; Matsko, A B; Seidel, D; Maleki, L

    2010-05-15

    We report the development and demonstration of an X-band voltage-controlled photonic oscillator based on a whispering gallery mode resonator made of an electro-optic crystalline material. The oscillator has good spectral purity and wide, agile, linear tunability. We have modified the existing theoretical model of the opto-electronic oscillator to describe the performance of our tunable oscillator and have found a good agreement between the theoretical predictions and the measurement results. We show that the device is promising for higher-frequency applications where high-performance tunable oscillators with wide tunability do not exist.

  12. Crosslinguistic categories in morphosyntactic typology: Problems and prospects

    DEFF Research Database (Denmark)

    Rijkhoff, Jan

    2016-01-01

    This article offers a new, transparent method to construe morphosyntactic categories for cross-linguistic research. It avoids the problem of categorial confusion attested in major post-Greenbergian studies in morphosyntactic typology, in particular in probabilistic typological investigations, which...

  13. 40 CFR 98.330 - Definition of the source category.

    Science.gov (United States)

    2010-07-01

    ... (CONTINUED) MANDATORY GREENHOUSE GAS REPORTING Zinc Production § 98.330 Definition of the source category. The zinc production source category consists of zinc smelters and secondary zinc recycling facilities....

  14. 40 CFR 98.310 - Definition of the source category.

    Science.gov (United States)

    2010-07-01

    ... (CONTINUED) MANDATORY GREENHOUSE GAS REPORTING Titanium Dioxide Production § 98.310 Definition of the source category. The titanium dioxide production source category consists of facilities that use the chloride process to produce titanium dioxide....

  15. Cohomology of exact categories and (non-)additive sheaves

    CERN Document Server

    Kaledin, Dmitry

    2011-01-01

    We use (non-)additive sheaves to introduce an (absolute) notion of Hochschild cohomology for exact categories as Ext's in a suitable bisheaf category. We compare our approach to various definitions present in the literature.

  16. 12 CFR 565.3 - Notice of capital category.

    Science.gov (United States)

    2010-01-01

    ... association shall be deemed to be within a given capital category for purposes of section 38 of the FDI Act... FDI Act and this part or that the savings association's capital category has changed as provided...

  17. 12 CFR 208.42 - Notice of capital category.

    Science.gov (United States)

    2010-01-01

    ... member bank shall be deemed to be within a given capital category for purposes of section 38 of the FDI... Board to the bank of its capital category for purposes of section 38 of the FDI Act and this subpart...

  18. Voltage Management in Unbalanced Low Voltage Networks Using a Decoupled Phase-Tap-Changer Transformer

    OpenAIRE

    Coppo, Massimiliano; Turri, Roberto; Marinelli, Mattia; Han, Xue

    2014-01-01

    The paper studies a medium voltage-low voltage transformer with a decoupled on load tap changer capability on each phase. The overall objective is the evaluation of the potential benefits on a low voltage network of such possibility. A realistic Danish low voltage network is used for the analysis. The load profiles are characterized by using single phase measurement data on voltages, currents and active powers with a 10 minutes resolution. Different scenarios are considered: no tap action, th...

  19. On the string topology category of compact Lie groups

    OpenAIRE

    2013-01-01

    This paper examines the string topology category of a manifold, defined by Blumberg, Cohen and Teleman. Since the string topology category is a subcategory of a compactly generated triangulated category, the machinery of stratification, constructed by Benson, Krause and Iyengar, can be applied in order to gain an understanding of the string topology category. It is shown that an appropriate stratification holds when the manifold in question is a simply connected compact Lie group. This last r...

  20. The Development of Category Learning Strategies: What Makes the Difference?

    Science.gov (United States)

    Hammer, Rubi; Diesendruck, Gil; Weinshall, Daphna; Hochstein, Shaul

    2009-01-01

    Category learning can be achieved by identifying common features among category members, distinctive features among non-members, or both. These processes are psychologically and computationally distinct, and may have implications for the acquisition of categories at different hierarchical levels. The present study examines an account of children's…

  1. Induction from a Single Instance: Formation of a Novel Category.

    Science.gov (United States)

    Macario, Jason F.; And Others

    1990-01-01

    Preschoolers were shown three objects in a given category. Each object had two attribute dimensions. A target category object with two different attributes was presented. Information provided to the children through verbal labeling or variations in a given category attribute both elicited induction of the defining attribute in the novel target…

  2. The homotopy category of complexes of projective modules

    OpenAIRE

    Jorgensen, Peter

    2003-01-01

    The homotopy category of complexes of projective left-modules over any reasonably nice ring is proved to be a compactly generated triangulated category, and a duality is given between its subcategory of compact objects and the finite derived category of right-modules.

  3. The Development of Category Learning Strategies: What Makes the Difference?

    Science.gov (United States)

    Hammer, Rubi; Diesendruck, Gil; Weinshall, Daphna; Hochstein, Shaul

    2009-01-01

    Category learning can be achieved by identifying common features among category members, distinctive features among non-members, or both. These processes are psychologically and computationally distinct, and may have implications for the acquisition of categories at different hierarchical levels. The present study examines an account of children's…

  4. Conciliating neuroscience and phenomenology via category theory.

    Science.gov (United States)

    Ehresmann, Andrée C; Gomez-Ramirez, Jaime

    2015-12-01

    The paper discusses how neural and mental processes correlate for developing cognitive abilities like memory or spatial representation and allowing the emergence of higher cognitive processes up to embodied cognition, consciousness and creativity. It is done via the presentation of MENS (for Memory Evolutive Neural System), a mathematical methodology, based on category theory, which encompasses the neural and mental systems and analyzes their dynamics in the process of 'becoming'. Using the categorical notion of a colimit, it describes the generation of mental objects through the iterative binding of distributed synchronous assemblies of neurons, and presents a new rationale of spatial representation in the hippocampus (Gómez-Ramirez and Sanz, 2011). An important result is that the degeneracy of the neural code (Edelman, 1989) is the property allowing for the formation of mental objects and cognitive processes of increasing complexity order, with multiple neuronal realizabilities; it is essential "to explain certain empirical phenomena like productivity and systematicity of thought and thinking (Aydede 2010)". Rather than restricting the discourse to linguistics or philosophy of mind, the formal methods used in MENS lead to precise notions of Compositionality, Productivity and Systematicity, which overcome the dichotomic debate of classicism vs. connectionism and their multiple facets. It also allows developing the naturalized phenomenology approach asked for by Varela (1996) which "seeks articulations by mutual constraints between phenomena present in experience and the correlative field of phenomena established by the cognitive sciences", while avoiding their pitfalls.

  5. The Cape Observatory: all Categories of Heritage

    Science.gov (United States)

    Glass, Ian S.

    2012-09-01

    In this presentation I will give an outline of the various types of heritage related to the Royal Observatory, Cape of Good Hope, established in 1820 and now the headquarters campus of the South African Astronomical Observatory, located quite close to downtown Cape Town. In terms of tangible, fixed heritage, the campus itself, the domes and the various other buildings are obviously relevant. This category includes the Classical Revival Main Building of 1828 and the McClean dome of 1895 by the leading colonial architect Herbert Baker as well as many other buildings and even the graves of two directors. Tangible movable items include, in principle, the telescopes, the accessory instruments and many pieces of apparatus that have been preserved. In addition, extensive collections of antique paintings, drawings, furniture and books add to the site's cultural significance. Many of the Observatory's archives are still kept locally. The intangible heritage of the Observatory consists for example of its history, its major discoveries, its interaction with the City, its central role in the history of science in South Africa and its appeal as a living cultural institution. Especially notable were the observations by Henderson (ca 1831) leading to the distance of a Cen and the early sky survey known as the Cape Photographic Durchmusterung.

  6. 49 CFR 236.551 - Power supply voltage; requirement.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Power supply voltage; requirement. 236.551 Section... supply voltage; requirement. The voltage of power supply shall be maintained within 10 percent of rated voltage....

  7. The de Rham homotopy theory and differential graded category

    CERN Document Server

    Moriya, Syunji

    2009-01-01

    This paper is a generalization of arXiv:0810.0808. We develop the de Rham homotopy theory of not necessarily nilpotent spaces, using closed dg-categories and equivariant dg-algebras. We see these two algebraic objects correspond in a certain way. We prove an equivalence between the homotopy category of schematic homotopy types and a homotopy category of closed dg-categories. We give a description of homotopy invariants of spaces in terms of minimal models. The minimal model in this context behaves much like the Sullivan's minimal model. We also provide some examples. We prove an equivalence between fiberwise rationalizations and closed dg-categories with subsidiary data.

  8. Brain damage and semantic category dissociations: is the animals category easier for males?

    Science.gov (United States)

    Scotti, Stefania; Laiacona, Marcella; Capitani, Erminio

    2010-08-01

    Semantic dissociations show that biological stimuli present a further dissociation between animals and plant life. Almost all cases of greater impairment of plant life knowledge were males, suggesting a higher male familiarity with animals possibly derived from different daily activities. To verify this hypothesis, we collected familiarity ratings for normal males and females, for 288 animals, subdivided according to whether they were hunted/fished, or were used as food. The overall familiarity was almost identical between males and females. Males were more familiar with hunted animals, but for them also food animals were more familiar. There was not a consistent effect of hunting/fishing independently of the food/not food classification. The claim that males are generally more proficient with animals knowledge because most hunters/fishers are males seems rather simplistic, and the familiarity structure of the animals category is more complex. An evolution-based account is suggested for the category by sex interaction.

  9. Fuzzy functions: a fuzzy extension of the category SET and some related categories

    Directory of Open Access Journals (Sweden)

    Ulrich Höhle

    2000-10-01

    Full Text Available In research Works where fuzzy sets are used, mostly certain usual functions are taken as morphisms. On the other hand, the aim of this paper is to fuzzify the concept of a function itself. Namely, a certain class of L-relations F : X x Y -> L is distinguished which could be considered as fuzzy functions from an L-valued set (X,Ex to an L-valued set (Y,Ey. We study basic properties of these functions, consider some properties of the corresponding category of L-valued sets and fuzzy functions as well as briefly describe some categories related to algebra and topology with fuzzy functions in the role of morphisms.

  10. Voltage Unbalance Compensation with Smart Three-phase Loads

    DEFF Research Database (Denmark)

    Douglass, Philip; Trintis, Ionut; Munk-Nielsen, Stig

    2016-01-01

    voltage, but it does not reduce the negative sequence voltage. The controller that uses phase-phase voltage as input eliminates negative sequence voltage, and reduces voltage deviations from the average to approximately half their initial value. Current unbalance is reduced when the voltage unbalance...... is caused by asymmetrical loads. These results suggest that the optimal algorithm to reduce system unbalance depends on which system parameter is most important: phase-neutral voltage unbalance, phase-phase voltage unbalance, or current unbalance....

  11. PRIMENESS IN CATEGORY OF MODULES AND CATEGORY OF COMODULES OVER CORINGS

    Directory of Open Access Journals (Sweden)

    Indah Emilia Wijayanti

    2012-06-01

    Full Text Available We recall the notion of prie modules and use the analogue technique to define prime comodules and corings. Moreover, the related properties are of interest. We investigate the relation of primeness of C-comodule M and the dual algebra *C of a coring C, the relation to projectivity of a coring in the associated category, the implication of the primeness to the injective hull and product of prime coalgebras.

  12. Power conditioning using dynamic voltage restorers under different voltage sag types

    Directory of Open Access Journals (Sweden)

    Ahmed M. Saeed

    2016-01-01

    Full Text Available Voltage sags can be symmetrical or unsymmetrical depending on the causes of the sag. At the present time, one of the most common procedures for mitigating voltage sags is by the use of dynamic voltage restorers (DVRs. By definition, a DVR is a controlled voltage source inserted between the network and a sensitive load through a booster transformer injecting voltage into the network in order to correct any disturbance affecting a sensitive load voltage. In this paper, modelling of DVR for voltage correction using MatLab software is presented. The performance of the device under different voltage sag types is described, where the voltage sag types are introduced using the different types of short-circuit faults included in the environment of the MatLab/Simulink package. The robustness of the proposed device is evaluated using the common voltage sag indices, while taking into account voltage and current unbalance percentages, where maintaining the total harmonic distortion percentage of the load voltage within a specified range is desired. Finally, several simulation results are shown in order to highlight that the DVR is capable of effective correction of the voltage sag while minimizing the grid voltage unbalance and distortion, regardless of the fault type.

  13. Power conditioning using dynamic voltage restorers under different voltage sag types.

    Science.gov (United States)

    Saeed, Ahmed M; Abdel Aleem, Shady H E; Ibrahim, Ahmed M; Balci, Murat E; El-Zahab, Essam E A

    2016-01-01

    Voltage sags can be symmetrical or unsymmetrical depending on the causes of the sag. At the present time, one of the most common procedures for mitigating voltage sags is by the use of dynamic voltage restorers (DVRs). By definition, a DVR is a controlled voltage source inserted between the network and a sensitive load through a booster transformer injecting voltage into the network in order to correct any disturbance affecting a sensitive load voltage. In this paper, modelling of DVR for voltage correction using MatLab software is presented. The performance of the device under different voltage sag types is described, where the voltage sag types are introduced using the different types of short-circuit faults included in the environment of the MatLab/Simulink package. The robustness of the proposed device is evaluated using the common voltage sag indices, while taking into account voltage and current unbalance percentages, where maintaining the total harmonic distortion percentage of the load voltage within a specified range is desired. Finally, several simulation results are shown in order to highlight that the DVR is capable of effective correction of the voltage sag while minimizing the grid voltage unbalance and distortion, regardless of the fault type.

  14. Influence of emotionally charged information on category-based induction.

    Directory of Open Access Journals (Sweden)

    Jennifer Zhu

    Full Text Available Categories help us make predictions, or inductions, about new objects. However, we cannot always be certain that a novel object belongs to the category we are using to make predictions. In such cases, people should use multiple categories to make inductions. Past research finds that people often use only the most likely category to make inductions, even if it is not certain. In two experiments, subjects read stories and answered questions about items whose categorization was uncertain. In Experiment 1, the less likely category was either emotionally neutral or dangerous (emotionally charged or likely to pose a threat. Subjects used multiple categories in induction when one of the categories was dangerous but not when they were all neutral. In Experiment 2, the most likely category was dangerous. Here, people used multiple categories, but there was also an effect of avoidance, in which people denied that dangerous categories were the most likely. The attention-grabbing power of dangerous categories may be balanced by a higher-level strategy to reject them.

  15. Limits of generalization between categories and implications for theories of category specificity.

    Science.gov (United States)

    Bukach, Cindy M; Phillips, W Stewart; Gauthier, Isabel

    2010-10-01

    Both domain-specific and expertise accounts of category specialization assume that generalization occurs within a domain but not between domains. Yet it is often difficult to define the boundaries and critical features of object domains. Differences in how categories are defined make it difficult to adjudicate between accounts of category specificity and may lead to contradictory results. For example, evidence for whether car experts recruit the fusiform face area is mixed, and this inconsistency may be due to the inclusion of antique cars in one of those previous studies (e.g., Grill-Spector, Knouf, & Kanwisher, 2004). The present study tested the generalization of expertise from modern to antique cars and found that modern-car experts showed expert discrimination and holistic processing of modern cars but not of antique cars. These findings suggest that the neural specialization underlying perceptual expertise is highly specific and may not generalize to distinct subclasses, even when they share some degree of perceptual and conceptual features.

  16. On the Classification of Weakly Integral Modular Categories

    Energy Technology Data Exchange (ETDEWEB)

    Bruillard, Paul J.; Galindo, Cesar; Ng, Siu Hung; Plavnik, Julia Y.; Rowell, Eric C.; Wang, Zhenghan

    2016-09-01

    In this paper we classify all modular categories of dimension 4m, where m is an odd square-free integer, and all rank 6 and rank 7 weakly integral modular categories. This completes the classification of weakly integral modular categories through rank 7. In particular, our results imply that all integral modular categories of rank at most 7 are pointed (that is, every simple object has dimension 1). All the non-integral (but weakly integral) modular categories of ranks 6 and 7 have dimension 4m, with m an odd square free integer, so their classification is an application of our main result. The classification of rank 7 integral modular categories is facilitated by an analysis of the two group actions on modular categories: the Galois group of the field generated by the entries of the S-matrix and the group of invertible isomorphism classes of objects. We derive some valuable arithmetic consequences from these actions.

  17. Comparing English, Mandarin, and Russian Hydrographic and Terrain Categories

    Energy Technology Data Exchange (ETDEWEB)

    Feng, Chen-Chieh [National University of Singapore; Sorokine, Alexandre [ORNL

    2013-01-01

    The paper compares hydrographic and terrain categories in the geospatial data standards of the US, Taiwan, and Russian Federation where the dominant languages used are from di erent language families. It aims to identify structural and semantic di erences between similar categories across three geospatial data standards. By formalizing the data standard structures and identifying the properties that di erentiate sibling categories in each geospatial data standard using well-known formal relations and quality universals, we develop a common basis on which hydrographic and terrain categories in the three data standards can be compared. The result suggests that all three data standards structure categories with a mixture of relations with di erent meaning even though most of them are well-known relations in top-level ontologies. Similar categories can be found across all three standards but exact match between similar categories are rare.

  18. An introduction to the language of category theory

    CERN Document Server

    Roman, Steven

    2017-01-01

    This textbook provides an introduction to elementary category theory, with the aim of making what can be a confusing and sometimes overwhelming subject more accessible. In writing about this challenging subject, the author has brought to bear all of the experience he has gained in authoring over 30 books in university-level mathematics. The goal of this book is to present the five major ideas of category theory: categories, functors, natural transformations, universality, and adjoints in as friendly and relaxed a manner as possible while at the same time not sacrificing rigor. These topics are developed in a straightforward, step-by-step manner and are accompanied by numerous examples and exercises, most of which are drawn from abstract algebra. The first chapter of the book introduces the definitions of category and functor and discusses diagrams, duality, initial and terminal objects, special types of morphisms, and some special types of categories, particularly comma categories and hom-set categories. Chap...

  19. Category Number Impacts Rule-Based "and" Information-Integration Category Learning: A Reassessment of Evidence for Dissociable Category-Learning Systems

    Science.gov (United States)

    Stanton, Roger D.; Nosofsky, Robert M.

    2013-01-01

    Researchers have proposed that an explicit reasoning system is responsible for learning rule-based category structures and that a separate implicit, procedural-learning system is responsible for learning information-integration category structures. As evidence for this multiple-system hypothesis, researchers report a dissociation based on…

  20. EDUCATIONAL EVENT AS THE PEDAGOGICAL CATEGORY

    Directory of Open Access Journals (Sweden)

    Victor V. Lobanov

    2015-01-01

    Full Text Available The aim of the investigation is to reveal the essence of the educational event as a pedagogical category. The reason to study the issue is the methodological generality of the term that came into pedagogical everyday life, but which semantic content is still not clear enough. Methods. The methods involve a theoretical analysis of the philosophical and pedagogical literature on the study, the categorical analysis, surveys of students and teachers. Results. The concept content of «event» is looked upon in both historical scholarship and pedagogy, «educational event» is analyzed in unity with the «educational situation» and «educational process». The attitude of students and teachers to educational events was clarified through the surveys; emotional and rational responses of the respondents were differentiated and the peculiarities of events organization in the education system were classified. While teachers and students are considered as subjects of educational events, their goals are delineated. Scientific novelty. The author's own definition of is given. Educational event is defined as a specially organized and unique pedagogical fact limited, but not rigidly determined by the educational situation, and capable of changing the educational process going beyond the boundaries of its conformism. The formulation above is the result of analysis how the concepts of «event», «situation» and «process» may interact in pedagogical discourse. Practical significance. The results can be used while designing the educational programs and projects, as well as in the development of academic courses of innovative pedagogy. 

  1. Predicting Success Study Using Students GPA Category

    Directory of Open Access Journals (Sweden)

    Awan Setiawan

    2015-07-01

    Full Text Available Abstract. Maintaining student graduation rates are the main tasks of a University. High rates of student graduation and the quality of graduates is a success indicator of a university, which will have an impact on public confidence as stakeholders of higher education and the National Accreditation Board as a regulator (government. Making predictions of student graduation and determine the factors that hinders will be a valuable input for University. Data mining system facilitates the University to create the segmentation of students’ performance and prediction of their graduation. Segmentation of student by their performance can be classified in a quadrant chart is divided into 4 segments based on grade point average and the growth rate of students performance index per semester. Standard methodology in data mining i.e CRISP-DM (Cross Industry Standard Procedure for Data Mining will be implemented in this research. Making predictions, graduation can be done through the modeling process by utilizing the college database. Some algorithms such as C5, C & R Tree, CHAID, and Logistic Regression tested in order to find the best model. This research utilizes student performance data for several classes. Parameters used in addition to GPA also included the master's students data are expected to build the student profile data. The outcome of the study is the student category based on their study performance and prediction of graduation. Based on this prediction, the  university may recommend actions to be taken to improve the student  achievement index and graduation rates.Keywords: graduation, segmentation, quadrant GPA, data mining, modeling algorithms

  2. High voltage load resistor array

    Energy Technology Data Exchange (ETDEWEB)

    Lehmann, Monty Ray [Smithfield, VA

    2005-01-18

    A high voltage resistor comprising an array of a plurality of parallel electrically connected resistor elements each containing a resistive solution, attached at each end thereof to an end plate, and about the circumference of each of the end plates, a corona reduction ring. Each of the resistor elements comprises an insulating tube having an electrode inserted into each end thereof and held in position by one or more hose clamps about the outer periphery of the insulating tube. According to a preferred embodiment, the electrode is fabricated from stainless steel and has a mushroom shape at one end, that inserted into the tube, and a flat end for engagement with the end plates that provides connection of the resistor array and with a load.

  3. Voltage-Controlled Floating Resistor Using DDCC

    Directory of Open Access Journals (Sweden)

    M. Kumngern

    2011-04-01

    Full Text Available This paper presents a new simple configuration to realize the voltage-controlled floating resistor, which is suitable for integrated circuit implementation. The proposed resistor is composed of three main components: MOS transistor operating in the non-saturation region, DDCC, and MOS voltage divider. The MOS transistor operating in the non-saturation region is used to configure a floating linear resistor. The DDCC and the MOS transistor voltage divider are used for canceling the nonlinear component term of MOS transistor in the non-saturation region to obtain a linear current/voltage relationship. The DDCC is employed to provide a simple summer of the circuit. This circuit offers an ease for realizing the voltage divider circuit and the temperature effect that includes in term of threshold voltage can be compensated. The proposed configuration employs only 16 MOS transistors. The performances of the proposed circuit are simulated with PSPICE to confirm the presented theory.

  4. Programable Driver for Voltage-Controlled Oscillators

    Science.gov (United States)

    Fowler, L. E.; Mcneil, J. A.

    1985-01-01

    Electronically programable read-only memory (EPROM) and digital-to-analog converter provide customized time-varying voltage for frequency modulation. Voltage used to modulate IMPATT oscillator that serves as microwave pump for solid-state maser in low-noise amplifier. EPROM simple to tailor voltage waveform to suit characteristics of given maser. Digital information for waveform programed into EPROM chip; digital-to-analog converter reads information and produces corresponding analog wave. Principle readily adapted to other applications.

  5. Generator of ultrashort megavolt voltage pulses

    CERN Document Server

    Zheltov, K A; Shalimanov, V F

    2002-01-01

    Paper describes approx 3 ns duration and > 1 MW amplitude voltage pulse generator under high-ohmic (approx 450 Ohm) load. Generator comprises pulse transformer with magnetized core, as well as, resonance tuned circuit of high-voltage solenoid and accumulating spaces of a shaping line containing, moreover, spark gap to switch charge in transmitting line. Paper contains the results of voltage measuring in generator basic units

  6. Investigation of pulsed voltage limiters characteristics

    Directory of Open Access Journals (Sweden)

    Karimov A. V.

    2012-06-01

    Full Text Available A new method for measuring the voltage limit is offered. It has been designed to measure high-power pulsed current of voltage limiters. The error of this method is half as much as the error of the known method of direct measurement. The investigation of dependence of power capability of single-crystal and double-crystal voltage limiters and of the pulsed operation time on pulse duration.

  7. Low-Voltage Switched-Capacitor Circuits

    DEFF Research Database (Denmark)

    Bidari, E.; Keskin, M.; Maloberti, F.

    1999-01-01

    Switched-capacitor stages are described which can function with very low (typically 1 V) supply voltages, without using voltage boosting or switched op-amps. Simulations indicate that high performance may be achieved using these circuits in filter or data converter applications.......Switched-capacitor stages are described which can function with very low (typically 1 V) supply voltages, without using voltage boosting or switched op-amps. Simulations indicate that high performance may be achieved using these circuits in filter or data converter applications....

  8. Microprocessor-controlled, programmable ramp voltage generator

    Energy Technology Data Exchange (ETDEWEB)

    Hopwood, J.

    1978-11-01

    A special-purpose voltage generator has been developed for driving the quadrupole mass filter of a residual gas analyzer. The generator is microprocessor-controlled with desired ramping parameters programmed by setting front-panel digital thumb switches. The start voltage, stop voltage, and time of each excursion are selectable. A maximum of five start-stop levels may be pre-selected for each program. The ramp voltage is 0 to 10 volts with sweep times from 0.1 to 999.99 seconds.

  9. Magnetoelectric voltage coefficients of magnetoelectric composites

    Institute of Scientific and Technical Information of China (English)

    WAN Yong-ping; ZHONG Zheng; QIU Jin-hao

    2006-01-01

    The magnetoelectric(ME) effect of the particulate magnetostrictive/piezoelectric composite was theoretically studied. The dependence of the ME voltage coefficients on the material properties of the magnetostrictive phase was discussed. The permittivity,permeability and the elastic modulus of the magnetostrictive phase generally have obvious influences on the ME voltage coefficients. The magnetostrictive phase with a large permittivity,large permeability or stiffer modulus will respectively contribute to the higher ME voltage coefficients. For a certain kind of piezoelectric matrix,the ME voltage coefficients can be improved to some extent by choosing those magnetostrictive materials with large permittivity,permeability or high elastic modulus.

  10. Maximum permissible voltage of YBCO coated conductors

    Energy Technology Data Exchange (ETDEWEB)

    Wen, J.; Lin, B.; Sheng, J.; Xu, J.; Jin, Z. [Department of Electrical Engineering, Shanghai Jiao Tong University, Shanghai (China); Hong, Z., E-mail: zhiyong.hong@sjtu.edu.cn [Department of Electrical Engineering, Shanghai Jiao Tong University, Shanghai (China); Wang, D.; Zhou, H.; Shen, X.; Shen, C. [Qingpu Power Supply Company, State Grid Shanghai Municipal Electric Power Company, Shanghai (China)

    2014-06-15

    Highlights: • We examine three kinds of tapes’ maximum permissible voltage. • We examine the relationship between quenching duration and maximum permissible voltage. • Continuous I{sub c} degradations under repetitive quenching where tapes reaching maximum permissible voltage. • The relationship between maximum permissible voltage and resistance, temperature. - Abstract: Superconducting fault current limiter (SFCL) could reduce short circuit currents in electrical power system. One of the most important thing in developing SFCL is to find out the maximum permissible voltage of each limiting element. The maximum permissible voltage is defined as the maximum voltage per unit length at which the YBCO coated conductors (CC) do not suffer from critical current (I{sub c}) degradation or burnout. In this research, the time of quenching process is changed and voltage is raised until the I{sub c} degradation or burnout happens. YBCO coated conductors test in the experiment are from American superconductor (AMSC) and Shanghai Jiao Tong University (SJTU). Along with the quenching duration increasing, the maximum permissible voltage of CC decreases. When quenching duration is 100 ms, the maximum permissible of SJTU CC, 12 mm AMSC CC and 4 mm AMSC CC are 0.72 V/cm, 0.52 V/cm and 1.2 V/cm respectively. Based on the results of samples, the whole length of CCs used in the design of a SFCL can be determined.

  11. Inductive voltage divider modeling in Matlab

    Science.gov (United States)

    Andreev, S. A.; Kim, V. L.

    2017-01-01

    Inductive voltage dividers have the most appropriate metrological characteristics on alternative current and are widely used for converting physical signals. The model of a double-decade inductive voltage divider was designed with the help of Matlab/Simulink. The first decade is an inductive voltage divider with balanced winding, the second decade is a single-stage inductive voltage divider. In the paper, a new transfer function algorithm was given. The study shows errors and differences that appeared between the third degree reduced model and a twenty degree unreduced model. The obtained results of amplitude error differ no more than by 7 % between the reduced and unreduced model.

  12. Development of a voltage scanner of chopper

    CERN Document Server

    Shen Guan Ren; LiShengLi; WangQuanXing; Wu Long Cheng

    2001-01-01

    Development of voltage sweeper of chopper with CPNG are introduced. Voltage sweeper is one of important key parts of chopper. Two years working prove that it is stable and reliable. Its main technology performance save: sine wave frequency: 750 kHz +- 20 Hz; total distortion: 65 Db; output voltage (V-V): 0->=4000 V; the error7 W; voltage supply: 220V AC +-10%, 50 +- 1 Hz; total power supply: <100W; Work temperature range: 0 - 40 degree; Stability in long time <=1%

  13. Disturbance Attenuation of DC Voltage Droop Control Structures in a Multi-Terminal HVDC Grid

    DEFF Research Database (Denmark)

    Thams, Florian; Chatzivasileiadis, Spyros; Prieto-Araujo, Eduardo

    2017-01-01

    of the disturbance rejection of these droop control structures. The approach is based on multi-variable frequency response analysis where both ac and dc grid dynamics are incorporated. In particular, the amplification of dc voltage oscillations due to wind power variations is analyzed using singular value analysis......DC voltage droop control is seen as the preferred control structure for primary voltage control of future multiterminal HVDC systems. Different droop control structures have been proposed in literature which can be classified in eight categories. This paper contributes to an analysis....... Further, the impact of dc cable modeling on the results is discussed. In addition, it is shown that the maximum singular value limits, frequently used in literature for MIMO-analysis, are not sufficient to prove that the impact of certain disturbances on analyzed outputs is within a certain boundary...

  14. Category and perceptual learning in subjects with treated Wilson's disease.

    Directory of Open Access Journals (Sweden)

    Pengjing Xu

    Full Text Available To explore the relationship between category and perceptual learning, we examined both category and perceptual learning in patients with treated Wilson's disease (WD, whose basal ganglia, known to be important in category learning, were damaged by the disease. We measured their learning rate and accuracy in rule-based and information-integration category learning, and magnitudes of perceptual learning in a wide range of external noise conditions, and compared the results with those of normal controls. The WD subjects exhibited deficits in both forms of category learning and in perceptual learning in high external noise. However, their perceptual learning in low external noise was relatively spared. There was no significant correlation between the two forms of category learning, nor between perceptual learning in low external noise and either form of category learning. Perceptual learning in high external noise was, however, significantly correlated with information-integration but not with rule-based category learning. The results suggest that there may be a strong link between information-integration category learning and perceptual learning in high external noise. Damage to brain structures that are important for information-integration category learning may lead to poor perceptual learning in high external noise, yet spare perceptual learning in low external noise. Perceptual learning in high and low external noise conditions may involve separate neural substrates.

  15. Category and Perceptual Learning in Subjects with Treated Wilson's Disease

    Science.gov (United States)

    Xu, Pengjing; Lu, Zhong-Lin; Wang, Xiaoping; Dosher, Barbara; Zhou, Jiangning; Zhang, Daren; Zhou, Yifeng

    2010-01-01

    To explore the relationship between category and perceptual learning, we examined both category and perceptual learning in patients with treated Wilson's disease (WD), whose basal ganglia, known to be important in category learning, were damaged by the disease. We measured their learning rate and accuracy in rule-based and information-integration category learning, and magnitudes of perceptual learning in a wide range of external noise conditions, and compared the results with those of normal controls. The WD subjects exhibited deficits in both forms of category learning and in perceptual learning in high external noise. However, their perceptual learning in low external noise was relatively spared. There was no significant correlation between the two forms of category learning, nor between perceptual learning in low external noise and either form of category learning. Perceptual learning in high external noise was, however, significantly correlated with information-integration but not with rule-based category learning. The results suggest that there may be a strong link between information-integration category learning and perceptual learning in high external noise. Damage to brain structures that are important for information-integration category learning may lead to poor perceptual learning in high external noise, yet spare perceptual learning in low external noise. Perceptual learning in high and low external noise conditions may involve separate neural substrates. PMID:20224790

  16. Excitation of voltage oscillations in an induction voltage adder

    Directory of Open Access Journals (Sweden)

    Nichelle Bruner

    2009-07-01

    Full Text Available The induction voltage adder is an accelerator architecture used in recent designs of pulsed-power driven x-ray radiographic systems such as Sandia National Laboratories’ Radiographic Integrated Test Stand (RITS, the Atomic Weapons Establishment’s planned Hydrus Facility, and the Naval Research Laboratory’s Mercury. Each of these designs relies on magnetic insulation to prevent electron loss across the anode-cathode gap in the vicinity of the adder as well as in the coaxial transmission line. Particle-in-cell simulations of the RITS adder and transmission line show that, as magnetic insulation is being established during a pulse, some electron loss occurs across the gap. Sufficient delay in the cavity pulse timings provides an opportunity for high-momentum electrons to deeply penetrate the cavities of the adder cells where they can excite radio-frequency resonances. These oscillations may be amplified in subsequent gaps, resulting in oscillations in the output power. The specific modes supported by the RITS-6 accelerator and details of the mechanism by which they are excited are presented in this paper.

  17. A Synchrophasor Based Optimal Voltage Control Scheme with Successive Voltage Stability Margin Improvement

    Directory of Open Access Journals (Sweden)

    Heng-Yi Su

    2016-01-01

    Full Text Available This paper proposes an optimal control scheme based on a synchronized phasor (synchrophasor for power system secondary voltage control. The framework covers voltage stability monitoring and control. Specifically, a voltage stability margin estimation algorithm is developed and built in the newly designed adaptive secondary voltage control (ASVC method to achieve more reliable and efficient voltage regulation in power systems. This new approach is applied to improve voltage profile across the entire power grid by an optimized plan for VAR (reactive power sources allocation; therefore, voltage stability margin of a power system can be increased to reduce the risk of voltage collapse. An extensive simulation study on the IEEE 30-bus test system is carried out to demonstrate the feasibility and effectiveness of the proposed scheme.

  18. Evaluation of the Voltage Support Strategies for the Low Voltage Grid Connected PV

    DEFF Research Database (Denmark)

    Demirok, Erhan; Sera, Dezso; Teodorescu, Remus

    2010-01-01

    PVs. In order to increase PV penetration level further, new voltage support control functions for individual inverters are required. This paper investigates distributed reactive power regulation and active power curtailment strategies regarding the development of PV connection capacity by evaluation......Admissible range of grid voltage is one of the strictest constraints for the penetration of distributed photovoltaic (PV) generators especially connection to low voltage (LV) public networks. Voltage limits are usually fulfilled either by network reinforcements or limiting of power injections from...

  19. Algebras of higher operads as enriched categories II

    CERN Document Server

    Batanin, Michael; Weber, Mark

    2009-01-01

    One of the open problems in higher category theory is the systematic construction of the higher dimensional analogues of the Gray tensor product. In this paper we continue the work of [7] to adapt the machinery of globular operads [4] to this task. The resulting theory includes the Gray tensor product of 2-categories and the Crans tensor product [12] of Gray categories. Moreover much of the previous work on the globular approach to higher category theory is simplified by our new foundations, and we illustrate this by giving an expedited account of many aspects of Cheng's analysis [11] of Trimble's definition of weak n-category. By way of application we obtain an "Ekmann-Hilton" result for braided monoidal 2-categories, and give the construction of a tensor product of A-infinity algebras.

  20. Category mistakes: A barrier to effective environmental management.

    Science.gov (United States)

    Wallace, Ken J; Jago, Mark

    2017-09-01

    How entities, the things that exist, are defined and categorised affects all aspects of environmental management including technical descriptions, quantitative analyses, participatory processes, planning, and decisions. Consequently, ambiguous definitions and wrongly assigning entities to categories, referred to as category mistakes, are barriers to effective management. Confusion caused by treating the term 'biodiversity' variously as the property of an area, the biota of an area, and a preferred end state (a value) - quite different categories of entities - is one example. To overcome such difficulties, we develop and define four entity categories - elements, processes, properties, and values - and two derived categories - states and systems. We argue that adoption of these categories and definitions will significantly improve environmental communication and analysis, and thus strengthen planning and decision-making. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. A role for the developing lexicon in phonetic category acquisition.

    Science.gov (United States)

    Feldman, Naomi H; Griffiths, Thomas L; Goldwater, Sharon; Morgan, James L

    2013-10-01

    Infants segment words from fluent speech during the same period when they are learning phonetic categories, yet accounts of phonetic category acquisition typically ignore information about the words in which sounds appear. We use a Bayesian model to illustrate how feedback from segmented words might constrain phonetic category learning by providing information about which sounds occur together in words. Simulations demonstrate that word-level information can successfully disambiguate overlapping English vowel categories. Learning patterns in the model are shown to parallel human behavior from artificial language learning tasks. These findings point to a central role for the developing lexicon in phonetic category acquisition and provide a framework for incorporating top-down constraints into models of category learning.

  2. Categorical perception of color: evidence from secondary category boundary

    Directory of Open Access Journals (Sweden)

    Al-rasheed AS

    2015-11-01

    Full Text Available Abdulrahman Saud Al-rasheed Department of Psychology, King Saud University, Riyadh, Kingdom of Saudi Arabia Abstract: Despite a plethora of behavioral research exploring the phenomenon of color categorical perception (CP known as "better discrimination between pair of colors stimuli from different categories and pair of colors stimuli from the same category even when the stimulus differences between the pairs of stimuli are equal", most of the evidence for the CP of color was derived from Roman or top-to-down script readers and very rarely from right-to-left script readers in primary category. To date, no studies of color CP have been conducted on right-to-left script readers in secondary category boundary to support this theory. Three experiments have been conducted: Experiments 1 and 2 established the Arabic blue–purple secondary category boundary, and Experiment 3 tested the CP of color in the blue–purple category boundary. Sixty participants (30 men and 30 women took part in this study. All spoke Arabic as their first language, and all were undergraduate or postgraduate students at King Saud University. Their ages ranged from 18–35 years with a mean age of 21.9 years (SD =5.2. The result indicated that for Experiments 1 and 2, it appeared that the Arabic blue–purple category boundary was approximately 10PB and it is in the same location as for English. For Experiment 3, reaction times in the between-categories condition were significantly faster than those in the within-category condition; this suggested that CP of color was shown in the Arabic's blue–purple secondary category boundary. Keywords: categorical perception, CP of color, categorization, blue–purple category boundary, secondary category boundary

  3. Influence of current limitation on voltage stability with voltage sourced converter HVDC

    DEFF Research Database (Denmark)

    Zeni, Lorenzo; Jóhannsson, Hjörtur; Hansen, Anca Daniela;

    2013-01-01

    A first study of voltage stability with relevant amount of Voltage Sourced Converter based High Voltage Direct Current (VSC-HVDC) transmission is presented, with particular focus on the converters’ behaviour when reaching their rated current. The detrimental effect of entering the current...

  4. Voltage stability in low voltage microgrids in aspects of active and reactive power demand

    Directory of Open Access Journals (Sweden)

    Parol Mirosław

    2016-03-01

    Full Text Available Low voltage microgrids are autonomous subsystems, in which generation, storage and power and electrical energy consumption appear. In the paper the main attention has been paid to the voltage stability issue in low voltage microgrid for different variants of its operation. In the introduction a notion of microgrid has been presented, and also the issue of influence of active and reactive power balance on node voltage level has been described. Then description of voltage stability issue has been presented. The conditions of voltage stability and indicators used to determine voltage stability margin in the microgrid have been described. Description of the low voltage test microgrid, as well as research methodology along with definition of considered variants of its operation have been presented further. The results of exemplary calculations carried out for the daily changes in node load of the active and reactive power, i.e. the voltage and the voltage stability margin indexes in nodes have been presented. Furthermore, the changes of voltage stability margin indexes depending on the variant of the microgrid operation have been presented. Summary and formulation of conclusions related to the issue of voltage stability in microgrids have been included at the end of the paper.

  5. Reduced Voltage Scaling in Clock Distribution Networks

    Directory of Open Access Journals (Sweden)

    Khader Mohammad

    2009-01-01

    Full Text Available We propose a novel circuit technique to generate a reduced voltage swing (RVS signals for active power reduction on main buses and clocks. This is achieved without performance degradation, without extra power supply requirement, and with minimum area overhead. The technique stops the discharge path on the net that is swinging low at a certain voltage value. It reduces active power on the target net by as much as 33% compared to traditional full swing signaling. The logic 0 voltage value is programmable through control bits. If desired, the reduced-swing mode can also be disabled. The approach assumes that the logic 0 voltage value is always less than the threshold voltage of the nMOS receivers, which eliminate the need of the low to high voltage translation. The reduced noise margin and the increased leakage on the receiver transistors using this approach have been addressed through the selective usage of multithreshold voltage (MTV devices and the programmability of the low voltage value.

  6. Low-Voltage Continuous Electrospinning Patterning.

    Science.gov (United States)

    Li, Xia; Li, Zhaoying; Wang, Liyun; Ma, Guokun; Meng, Fanlong; Pritchard, Robyn H; Gill, Elisabeth L; Liu, Ye; Huang, Yan Yan Shery

    2016-11-30

    Electrospinning is a versatile technique for the construction of microfibrous and nanofibrous structures with considerable potential in applications ranging from textile manufacturing to tissue engineering scaffolds. In the simplest form, electrospinning uses a high voltage of tens of thousands volts to draw out ultrafine polymer fibers over a large distance. However, the high voltage limits the flexible combination of material selection, deposition substrate, and control of patterns. Prior studies show that by performing electrospinning with a well-defined "near-field" condition, the operation voltage can be decreased to the kilovolt range, and further enable more precise patterning of fibril structures on a planar surface. In this work, by using solution dependent "initiators", we demonstrate a further lowering of voltage with an ultralow voltage continuous electrospinning patterning (LEP) technique, which reduces the applied voltage threshold to as low as 50 V, simultaneously permitting direct fiber patterning. The versatility of LEP is shown using a wide range of combination of polymer and solvent systems for thermoplastics and biopolymers. Novel functionalities are also incorporated when a low voltage mode is used in place of a high voltage mode, such as direct printing of living bacteria; the construction of suspended single fibers and membrane networks. The LEP technique reported here should open up new avenues in the patterning of bioelements and free-form nano- to microscale fibrous structures.

  7. Modeling and Simulation of Low Voltage Arcs

    NARCIS (Netherlands)

    Ghezzi, L.; Balestrero, A.

    2010-01-01

    Modeling and Simulation of Low Voltage Arcs is an attempt to improve the physical understanding, mathematical modeling and numerical simulation of the electric arcs that are found during current interruptions in low voltage circuit breakers. An empirical description is gained by refined electrical

  8. High-voltage engineering and testing

    CERN Document Server

    Ryan, Hugh M

    2013-01-01

    This 3rd edition of High Voltage Engineering Testing describes strategic developments in the field and reflects on how they can best be managed. All the key components of high voltage and distribution systems are covered including electric power networks, UHV and HV. Distribution systems including HVDC and power electronic systems are also considered.

  9. Modeling and Simulation of Low Voltage Arcs

    NARCIS (Netherlands)

    Ghezzi, L.; Balestrero, A.

    2010-01-01

    Modeling and Simulation of Low Voltage Arcs is an attempt to improve the physical understanding, mathematical modeling and numerical simulation of the electric arcs that are found during current interruptions in low voltage circuit breakers. An empirical description is gained by refined electrical m

  10. Voltage-gated lipid ion channels

    DEFF Research Database (Denmark)

    Blicher, Andreas; Heimburg, Thomas Rainer

    2013-01-01

    Synthetic lipid membranes can display channel-like ion conduction events even in the absence of proteins. We show here that these events are voltage-gated with a quadratic voltage dependence as expected from electrostatic theory of capacitors. To this end, we recorded channel traces and current...

  11. Generalized trace and modified dimension functions on ribbon categories

    CERN Document Server

    Geer, Nathan; Patureau-Mirand, Bertrand

    2010-01-01

    In this paper we use topological techniques to construct generalized trace and modified dimension functions on ideals in certain ribbon categories. Examples of such ribbon categories naturally arise in representation theory where the usual trace and dimension functions are zero, but these generalized trace and modified dimension functions are non-zero. Such examples include categories of finite dimensional modules of certain Lie algebras and finite groups over a field of positive characteristic and categories of finite dimensional modules of basic Lie superalgebras over the complex numbers. These modified dimensions can be interpreted categorically and are closely related to some basic notions from representation theory.

  12. On Anaphora and the Binding Principles in Categorial Grammar

    Science.gov (United States)

    Morrill, Glyn; Valentín, Oriol

    In type logical categorial grammar the analysis of an expression is a resource-conscious proof. Anaphora represents a particular challenge to this approach in that the antecedent resource is multiplied in the semantics. This duplication, which corresponds logically to the structural rule of contraction, may be treated lexically or syntactically. Furthermore, anaphora is subject to constraints, which Chomsky (1981) formulated as Binding Principles A, B, and C. In this paper we consider English anaphora in categorial grammar including reference to the binding principles. We invoke displacement calculus, modal categorial calculus, categorial calculus with limited contraction, and entertain addition of negation as failure.

  13. Multilevel induction of categories: venomous snakes hijack the learning of lower category levels.

    Science.gov (United States)

    Noh, Sharon M; Yan, Veronica X; Vendetti, Michael S; Castel, Alan D; Bjork, Robert A

    2014-08-01

    The induction of categories and concepts from examples-which plays an important role in how people come to organize and understand the world-can happen at multiple levels, but how do competing values at these different levels affect learning? Using perceptually rich images of snakes, we asked participants to attend to either the snakes' specific genus or a broader categorization and then tested induction at both levels. We also varied the intrinsic value of the broader categorization (high value: whether the snake was venomous; low value: whether it was tropical). We found an interaction between study instruction and intrinsic value: Participants in the low-value condition were better able to induce the level they were instructed to attend to (i.e., genus or broader category) than to induce the level they were not instructed to attend to, whereas participants in the high-value condition, regardless of the level of categorization they were instructed to attend to, were significantly better at learning the broad categorization (for them, whether the snake was venomous) than were participants in the low-value condition. Our results suggest that intrinsically valuable features can disrupt the intentional learning of other, task-relevant information, but enhance the incidental learning of the same information.

  14. Categorial compositionality: a category theory explanation for the systematicity of human cognition.

    Science.gov (United States)

    Phillips, Steven; Wilson, William H

    2010-07-22

    Classical and Connectionist theories of cognitive architecture seek to explain systematicity (i.e., the property of human cognition whereby cognitive capacity comes in groups of related behaviours) as a consequence of syntactically and functionally compositional representations, respectively. However, both theories depend on ad hoc assumptions to exclude specific instances of these forms of compositionality (e.g. grammars, networks) that do not account for systematicity. By analogy with the Ptolemaic (i.e. geocentric) theory of planetary motion, although either theory can be made to be consistent with the data, both nonetheless fail to fully explain it. Category theory, a branch of mathematics, provides an alternative explanation based on the formal concept of adjunction, which relates a pair of structure-preserving maps, called functors. A functor generalizes the notion of a map between representational states to include a map between state transformations (or processes). In a formal sense, systematicity is a necessary consequence of a higher-order theory of cognitive architecture, in contrast to the first-order theories derived from Classicism or Connectionism. Category theory offers a re-conceptualization for cognitive science, analogous to the one that Copernicus provided for astronomy, where representational states are no longer the center of the cognitive universe--replaced by the relationships between the maps that transform them.

  15. Practical considerations in voltage stability assessment

    Energy Technology Data Exchange (ETDEWEB)

    Kundur, P.; Gao, B. [Powertech Labs. Inc., Surrey, BC (Canada)

    1994-12-31

    This paper deals with some of the most important practical issues related to voltage stability assessment of large practical systems. A brief discussion of the practical aspects of voltage stability problem and prevention of voltage instability is given first, followed by descriptions of different analytical techniques and tools for voltage stability analysis. Presentations of analytical tools is focused on the VSTAB program which incorporates the modal analysis, continuation power flow, and shortest distance to instability techniques, Finally, an example case study of a practical large system is presented. The case study illustrates how modal analysis is used to determine the most effective load shedding scheme for preventing voltage instability. (author) 15 refs., 2 figs., 2 tabs.

  16. Radiatively heated high voltage pyroelectric crystal pulser

    Energy Technology Data Exchange (ETDEWEB)

    Antolak, A.J., E-mail: antolak@sandia.gov [Sandia National Laboratories, Livermore, CA 94550 (United States); Chen, A.X. [Sandia National Laboratories, Livermore, CA 94550 (United States); Leung, K.-N. [Sandia National Laboratories, Livermore, CA 94550 (United States); Nuclear Engineering Department, University of California, Berkeley (United States); Morse, D.H.; Raber, T.N. [Sandia National Laboratories, Livermore, CA 94550 (United States)

    2014-01-21

    Thin lithium tantalate pyroelectric crystals in a multi-stage pulser were heated by quartz lamps during their charging phase to generate high voltage pulses. The charging voltage was determined empirically based on the measured breakdown voltage in air and verified by the induced breakdown voltage of an external high voltage power supply. A four-stage pyroelectric crystal device generated pulse discharges of up to 86 kV using both quartz lamps (radiative) and thermoelectric (conductive) heating. Approximately 50 mJ of electrical energy was harvested from the crystals when radiatively heated in air, and up to 720 mJ was produced when the crystals were submerged in a dielectric fluid. It is anticipated that joule-level pulse discharges could be obtained by employing additional stages and optimizing the heating configuration.

  17. Non-contact current and voltage sensor

    Science.gov (United States)

    Carpenter, Gary D; El-Essawy, Wael; Ferreira, Alexandre Peixoto; Keller, Thomas Walter; Rubio, Juan C; Schappert, Michael A

    2014-03-25

    A detachable current and voltage sensor provides an isolated and convenient device to measure current passing through a conductor such as an AC branch circuit wire, as well as providing an indication of an electrostatic potential on the wire, which can be used to indicate the phase of the voltage on the wire, and optionally a magnitude of the voltage. The device includes a housing that contains the current and voltage sensors, which may be a ferrite cylinder with a hall effect sensor disposed in a gap along the circumference to measure current, or alternative a winding provided through the cylinder along its axis and a capacitive plate or wire disposed adjacent to, or within, the ferrite cylinder to provide the indication of the voltage.

  18. Voltage-gated lipid ion channels

    DEFF Research Database (Denmark)

    Blicher, Andreas; Heimburg, Thomas Rainer

    2013-01-01

    Synthetic lipid membranes can display channel-like ion conduction events even in the absence of proteins. We show here that these events are voltage-gated with a quadratic voltage dependence as expected from electrostatic theory of capacitors. To this end, we recorded channel traces and current...... histograms in patch-experiments on lipid membranes. We derived a theoretical current-voltage relationship for pores in lipid membranes that describes the experimental data very well when assuming an asymmetric membrane. We determined the equilibrium constant between closed and open state and the open...... probability as a function of voltage. The voltage-dependence of the lipid pores is found comparable to that of protein channels. Lifetime distributions of open and closed events indicate that the channel open distribution does not follow exponential statistics but rather power law behavior for long open times...

  19. Coordinated Voltage Control of Active Distribution Network

    Directory of Open Access Journals (Sweden)

    Xie Jiang

    2016-01-01

    Full Text Available This paper presents a centralized coordinated voltage control method for active distribution network to solve off-limit problem of voltage after incorporation of distributed generation (DG. The proposed method consists of two parts, it coordinated primal-dual interior point method-based voltage regulation schemes of DG reactive powers and capacitors with centralized on-load tap changer (OLTC controlling method which utilizes system’s maximum and minimum voltages, to improve the qualified rate of voltage and reduce the operation numbers of OLTC. The proposed coordination has considered the cost of capacitors. The method is tested using a radial edited IEEE-33 nodes distribution network which is modelled using MATLAB.

  20. Hysteresis in voltage-gated channels.

    Science.gov (United States)

    Villalba-Galea, Carlos A

    2016-09-30

    Ion channels constitute a superfamily of membrane proteins found in all living creatures. Their activity allows fast translocation of ions across the plasma membrane down the ion's transmembrane electrochemical gradient, resulting in a difference in electrical potential across the plasma membrane, known as the membrane potential. A group within this superfamily, namely voltage-gated channels, displays activity that is sensitive to the membrane potential. The activity of voltage-gated channels is controlled by the membrane potential, while the membrane potential is changed by these channels' activity. This interplay produces variations in the membrane potential that have evolved into electrical signals in many organisms. These signals are essential for numerous biological processes, including neuronal activity, insulin release, muscle contraction, fertilization and many others. In recent years, the activity of the voltage-gated channels has been observed not to follow a simple relationship with the membrane potential. Instead, it has been shown that the activity of voltage-gated channel displays hysteresis. In fact, a growing number of evidence have demonstrated that the voltage dependence of channel activity is dynamically modulated by activity itself. In spite of the great impact that this property can have on electrical signaling, hysteresis in voltage-gated channels is often overlooked. Addressing this issue, this review provides examples of voltage-gated ion channels displaying hysteretic behavior. Further, this review will discuss how Dynamic Voltage Dependence in voltage-gated channels can have a physiological role in electrical signaling. Furthermore, this review will elaborate on the current thoughts on the mechanism underlying hysteresis in voltage-gated channels.

  1. 28 CFR 524.72 - CIM assignment categories.

    Science.gov (United States)

    2010-07-01

    ... 28 Judicial Administration 2 2010-07-01 2010-07-01 false CIM assignment categories. 524.72 Section... assignment categories. CIM cases are classified according to the following assignments: (a) Witness Security... or federal penal (which includes correctional and detention facilities) institutions. This assignment...

  2. Skew category algebras associated with partially defined dynamical systems

    DEFF Research Database (Denmark)

    Lundström, Patrik; Öinert, Per Johan

    2012-01-01

    We introduce partially defined dynamical systems defined on a topological space. To each such system we associate a functor s from a category G to Topop and show that it defines what we call a skew category algebra A ⋊σ G. We study the connection between topological freeness of s and, on the one...

  3. Models for $(\\infty, n)$-categories and the cobordism hypothesis

    CERN Document Server

    Bergner, Julia E

    2010-01-01

    In this paper we introduce the models for $(\\infty, n)$-categories which have been developed to date, as well as the comparisons between them that are known and conjectured. We review the role of $(\\infty, n)$-categories in the proof of the Cobordism Hypothesis.

  4. 40 CFR 98.260 - Definition of the source category.

    Science.gov (United States)

    2010-07-01

    ... the production unit or units identified by an individual identification number in an operating permit... (CONTINUED) MANDATORY GREENHOUSE GAS REPORTING Phosphoric Acid Production § 98.260 Definition of the source category. The phosphoric acid production source category consists of facilities with a...

  5. Category of trees in representation theory of quantum algebras

    Energy Technology Data Exchange (ETDEWEB)

    Moskaliuk, N. M.; Moskaliuk, S. S., E-mail: mss@bitp.kiev.ua [NAS of Ukraine, Bogolyubov Institute for Theoretical Physics (Ukraine)

    2013-10-15

    New applications of categorical methods are connected with new additional structures on categories. One of such structures in representation theory of quantum algebras, the category of Kuznetsov-Smorodinsky-Vilenkin-Smirnov (KSVS) trees, is constructed, whose objects are finite rooted KSVS trees and morphisms generated by the transition from a KSVS tree to another one.

  6. The Quotient Category of a Graded Morita-Takeuchi Context

    Institute of Scientific and Technical Information of China (English)

    F. CASTA(N)O IGLESIAS; C. N(A)ST(A)SESCU

    2006-01-01

    In this paper, we offer a graded equivalence between the quotient categories defined by any graded Morita Takeuchi context via certain modifications of the graded cotensor functors. As a consequence, we show a commutative diagram that establish the relation between the closed objects of the categories grC and MC, where C is a graded coalgebra.

  7. 14 CFR 61.68 - Category III pilot authorization requirements.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Category III pilot authorization requirements. 61.68 Section 61.68 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF... Ratings and Pilot Authorizations § 61.68 Category III pilot authorization requirements. (a) General....

  8. 40 CFR 98.270 - Definition of source category.

    Science.gov (United States)

    2010-07-01

    ...), produce paper products from purchased pulp, produce secondary fiber from recycled paper, convert paper... (CONTINUED) MANDATORY GREENHOUSE GAS REPORTING Pulp and Paper Manufacturing § 98.270 Definition of source category. (a) The pulp and paper manufacturing source category consists of facilities that produce...

  9. Learning Vowel Categories from Maternal Speech in Gurindji Kriol

    Science.gov (United States)

    Jones, Caroline; Meakins, Felicity; Muawiyath, Shujau

    2012-01-01

    Distributional learning is a proposal for how infants might learn early speech sound categories from acoustic input before they know many words. When categories in the input differ greatly in relative frequency and overlap in acoustic space, research in bilingual development suggests that this affects the course of development. In the present…

  10. Client contribution in negotiations on employability – categories revised?

    DEFF Research Database (Denmark)

    Eskelinen, L.; Olesen, Søren Peter; Caswell, D.

    2010-01-01

    . Second, the client introduces new categories that are compatible with the demands of the employment system. She contributes by drawing on discursive resources related to the category of ‘active job seeker’ but does this with an own agenda of looking for a suitable job. The analysis elucidates the client...

  11. Whittaker categories and strongly typical Whittaker modules for Lie superalgebras

    CERN Document Server

    Bagci, Irfan; Wiesner, Emilie

    2012-01-01

    Following analogous constructions for Lie algebras, we define Whittaker modules and Whittaker categories for finite-dimensional simple Lie superalgebras. Results include a decomposition of Whittaker categories for a Lie superalgebra according to the action of an appropriate sub-superalgebra; and, for basic classical Lie superalgebras of type I, a description of the strongly typical simple Whittaker modules.

  12. Representation of categories: metaphorical use of the container schema

    NARCIS (Netherlands)

    Boot, I.; Pecher, D.

    2011-01-01

    In the present study we investigated whether the mental representation of the concept categories is represented by the container image schema (Lakoff & Johnson, 1980). In two experiments participants decided whether two pictures were from the same category (animal or vehicle). Pictures were

  13. The size of patent categories: USPTO 1976-2006

    NARCIS (Netherlands)

    Lafond, F.D.

    2014-01-01

    Categorization is an important phenomenon in science and society, and classification systems reflect the mesoscale organization of knowledge. The Yule-Simon-Naranan model, which assumes exponential growth of the number of categories and exponential growth of individual categories predicts a power la

  14. Clustering and classification of music using interval categories

    NARCIS (Netherlands)

    Honingh, A.; Bod, R.

    2011-01-01

    We present a novel approach to clustering and classification of music, based on the concept of interval categories. Six interval categories exist, each with its own musical character. A piece of music can be represented by six numbers, reflecting the percentages of occurrences of each interval categ

  15. Closure Operators and Closure Systems on Quantaloid-Enriched Categories

    Institute of Scientific and Technical Information of China (English)

    Min LIU; Bin ZHAO

    2013-01-01

    In this paper,we introduce the fundamental notions of closure operator and closure system in the framework of quantaloid-enriched category.We mainly discuss the relationship between closure operators and adjunctions and establish the one-to-one correspondence between closure operators and closure systems on quantaloid-enriched categories.

  16. New Control Technique Applied in Dynamic Voltage Restorer for Voltage Sag Mitigation

    Directory of Open Access Journals (Sweden)

    Rosli Omar

    2010-01-01

    Full Text Available The Dynamic Voltage Restorer (DVR was a power electronics device that was able to compensate voltage sags on critical loads dynamically. The DVR consists of VSC, injection transformers, passive filters and energy storage (lead acid battery. By injecting an appropriate voltage, the DVR restores a voltage waveform and ensures constant load voltage. There were so many types of the control techniques being used in DVR for mitigating voltage sags. The efficiency of the DVR depends on the efficiency of the control technique involved in switching the inverter. Problem statement: Simulation and experimental investigation toward new algorithms development based on SVPWM. Understanding the nature of DVR and performance comparisons between the various controller technologies available. The proposed controller using space vector modulation techniques obtain higher amplitude modulation indexes if compared with conventional SPWM techniques. Moreover, space vector modulation techniques can be easily implemented using digital processors. Space vector PWM can produce about 15% higher output voltage than standard Sinusoidal PWM. Approach: The purpose of this research was to study the implementation of SVPWM in DVR. The proposed control algorithm was investigated through computer simulation by using PSCAD/EMTDC software. Results: From simulation and experimental results showed the effectiveness and efficiency of the proposed controller based on SVPWM in mitigating voltage sags in low voltage distribution systems. It was concluded that its controller also works well both in balance and unbalance conditions of voltages. Conclusion/Recommendations: The simulation and experimental results of a DVR using PSCAD/EMTDC software based on SVPWM technique showed clearly the performance of the DVR in mitigating voltage sags. The DVR operates without any difficulties to inject the appropriate voltage component to correct rapidly any anomaly in the supply voltage to keep the

  17. Anthropometric Profile in Different Event Categories of Acrobatic Gymnastics

    Science.gov (United States)

    Taboada-Iglesias, Yaiza; Santana, Mercedes Vernetta; Gutiérrez-Sánchez, Águeda

    2017-01-01

    Abstract There is a specific anthropometric profile for each sport, which may be differentiated even in relation to the position, role or event category within each sport discipline. However, there are few studies on acrobatic gymnastics, and the goal of this work was to determine the anthropometric profile depending on the event category, as well as factors that predisposed to performance in these categories. The sample consisted of 150 gymnasts from Spain, divided into 8 groups according to the event category and the role played. The kinanthropometric measurements were taken through the procedures established by the International Society for the Advancement of Kineantropometry. The anthropometric characteristics, including body mass index, somatotype, body composition and proportionality using the Phantom stratagem were analyzed, and the results obtained from the different groups were compared. A regression analysis was performed with particular groups of gymnasts. No significant differences (p gymnast toward choosing one event category or another, except for female bases. PMID:28713469

  18. Relational categories as a bridge between cognitive and educational research.

    Science.gov (United States)

    Goldwater, Micah B; Schalk, Lennart

    2016-07-01

    Both cognitive and educational psychology literature strive to investigate human category and concept learning. However, both literatures focus on different phenomena and often use different methodologies. We identify and discuss commonalities and differences between the literatures. This literature comparison reveals that research on relational category learning offers a promising avenue to integration. We suggest that this integration would be especially beneficial to advance our understanding of conceptual change essentially, how complex scientific concepts and categories are acquired and developed in educational contexts elaborating or correcting students' prior conceptions. Furthermore, the focus on relational categories allows us to provide an integrative discussion on how recent lines of research on analogy, memory and category learning, and knowledge restructuring relate to and can inform education. In general, this article advocates the complementary nature of cognitive and educational psychology and identifies viable, and potentially synergistic paths for future research. (PsycINFO Database Record

  19. Effect of social category priming on personal attitudes.

    Science.gov (United States)

    Kawakami, Kerry; Dovidio, John F; Dijksterhuis, Ap

    2003-07-01

    In four studies, we examined the spontaneous activation of specific attitudes related to social categories. These studies investigated whether priming participants with concepts associated with the elderly and skinheads influenced participants' attitudes. The results consistently demonstrated that priming a social category can influence people's attitudes such that they become more similar to those of people in the primed category. After participants were primed with the elderly category, their attitudes became more conservative; after participants were primed with the skinhead category, their attitudes became more prejudiced. We also found that these effects can occur without awareness and intention and are specific to the participants' own attitudes. The theoretical and practical implications of these findings are considered.

  20. Integral objects and Deligne's category Rep(S_t)

    CERN Document Server

    Del Padrone, Alessio

    2010-01-01

    We give negative answers to certain questions on abelian semisimple tensor categories raised by Bruno Kahn and Charles A. Weibel in connection with the preprint of Kahn "On the multiplicities of a motive" (arXiv:math/0610446), now published as Parts I and IV of "Zeta functions and motives", Pure Appl. Math. Q. 5 (2009), no. 1, part 2, 507-570. For the most interesting examples we used Deligne's category Rep(S_t,F) of representations of the "symmetric group S_t with t not an integer" with F any algebraically closed field of characteristic zero. This is an interesting family of tensor categories, "new" in some sense, interpolating the representations of the symmetric groups. Among other things we give two proofs that this category is not Schur-finite, showing hence explicitly that it is not tensor equivalent to a category of superepresentations of a supergroup.

  1. Fuel Cell/Electrochemical Cell Voltage Monitor

    Science.gov (United States)

    Vasquez, Arturo

    2012-01-01

    A concept has been developed for a new fuel cell individual-cell-voltage monitor that can be directly connected to a multi-cell fuel cell stack for direct substack power provisioning. It can also provide voltage isolation for applications in high-voltage fuel cell stacks. The technology consists of basic modules, each with an 8- to 16-cell input electrical measurement connection port. For each basic module, a power input connection would be provided for direct connection to a sub-stack of fuel cells in series within the larger stack. This power connection would allow for module power to be available in the range of 9-15 volts DC. The relatively low voltage differences that the module would encounter from the input electrical measurement connection port, coupled with the fact that the module's operating power is supplied by the same substack voltage input (and so will be at similar voltage), provides for elimination of high-commonmode voltage issues within each module. Within each module, there would be options for analog-to-digital conversion and data transfer schemes. Each module would also include a data-output/communication port. Each of these ports would be required to be either non-electrical (e.g., optically isolated) or electrically isolated. This is necessary to account for the fact that the plurality of modules attached to the stack will normally be at a range of voltages approaching the full range of the fuel cell stack operating voltages. A communications/ data bus could interface with the several basic modules. Options have been identified for command inputs from the spacecraft vehicle controller, and for output-status/data feeds to the vehicle.

  2. High voltage electricity installations a planning perspective

    CERN Document Server

    Jay, Stephen Andrew

    2006-01-01

    The presence of high voltage power lines has provoked widespread concern for many years. High Voltage Electricity Installations presents an in-depth study of policy surrounding the planning of high voltage installations, discussing the manner in which they are percieved by the public, and the associated environmental issues. An analysis of these concerns, along with the geographical, environmental and political influences that shape their expression, is presented. Investigates local planning policy in an area of the energy sector that is of highly topical environmental and public concern Cover

  3. Piezoelectric Voltage Coupled Reentrant Cavity Resonator

    CERN Document Server

    Carvalho, Natalia C; Floch, Jean-Michel Le; Tobar, Michael Edmund

    2014-01-01

    A piezoelectric voltage coupled microwave reentrant cavity has been developed. The central cavity post is bonded to a piezoelectric actuator allowing the voltage control of small post displacements over a high dynamic range. We show that such a cavity can be implemented as a voltage tunable resonator, a transducer for exciting and measuring mechanical modes of the structure and a transducer for measuring comparative sensitivity of the piezoelectric material. Experiments were conducted at room and cryogenic temperatures with results verified using Finite Element software.

  4. Voltage controlled spintronics device for logic applications.

    Energy Technology Data Exchange (ETDEWEB)

    Bader, S. D.; You, C.-Y.

    1999-09-03

    We consider logic device concepts based on our previously proposed spintronics device element whose magnetization orientation is controlled by application of a bias voltage instead of a magnetic field. The basic building block is the voltage-controlled rotation (VCR) element that consists of a four-layer structure--two ferromagnetic layers separated by both nanometer-thick insulator and metallic spacer layers. The interlayer exchange coupling between the two ferromagnetic layers oscillates as a function of applied voltage. We illustrate transistor-like concepts and re-programmable logic gates based on VCR elements.

  5. Programmable high voltage power supply with regulation confined to the high voltage section

    Science.gov (United States)

    Castell, Karen D. (Inventor); Ruitberg, Arthur P. (Inventor)

    1994-01-01

    A high voltage power supply in a dc-dc converter configuration includes a pre-regulator which filters and regulates the dc input and drives an oscillator which applies, in turn, a low voltage ac signal to the low side of a step-up high voltage transformer. The high voltage side of the transformer drives a voltage multiplier which provides a stepped up dc voltage to an output filter. The output voltage is sensed by a feedback network which then controls a regulator. Both the input and output of the regulator are on the high voltage side, avoiding isolation problems. The regulator furnishes a portion of the drive to the voltage multiplier, avoiding having a regulator in series with the load with its attendant, relatively high power losses. This power supply is highly regulated, has low power consumption, a low parts count and may be manufactured at low cost. The power supply has a programmability feature that allows for the selection of a large range of output voltages.

  6. Transformerless DC-DC Converter Using Cockcroft-Walton Voltage Multiplier to Obtain High DC Voltage

    Directory of Open Access Journals (Sweden)

    Meghana G Naik,

    2014-11-01

    Full Text Available In the present scenario the use of transformer for high voltages in converter circuit reduces the overall operating efficiency due to leakage inductance and use of transformer also increases the operational cost. . Therefore the proposed system is implemented with transformer less DC-DC converter so as to obtain high DC voltage with the use of nine stage Cockcroft-Walton (CW voltage multiplier. The proposed converter operates in CCM (continuous conduction mode, so that the converter switch stress, the switching losses are reduced. The DC voltage at the input of the proposed model is low and is boosted up by boost inductor (Ls in DC-DC converter stage and performs inverter operation. The number of stages in CW-voltage multiplier circuit is applied with low input pulsating DC (AC Voltage voltage where it is getting converted to high DC output voltage. The proposed converter switches operates at two independent frequencies, modulating (fsm andalternating (fsc frequency. The fsm operates at higher frequency of the output while the fsc operates at lower frequency of the desired output voltage ripple and the output ripples can be adjusted by the switch Sc1 and Sc2. The regulation of the output voltage is achieved by controlling the Duty ratio.The simulation is carried over by the MATLABSIMULINK.

  7. Technical feasibility study of Voltage Optimization Unit

    DEFF Research Database (Denmark)

    Hu, Junjie; Marinelli, Mattia; Coppo, Massimiliano

    transformer with OLTC per phase is necessary and valuable. The main conclusion is that power distribution transformer with OLTC control on each phase can significantly improve the PV hosting capacity in the analyzed unbal-anced scenarios. To investigate the verification problem, a simulation study...... is performed using the soft-wares DigSilent PowerFactory and Matlab. In this simulation study, a real low voltage network from Dong Eldistribution is modeled in Powerfactory. The measured data of the real low voltage network is analyzed and the resulting loading profiles including active and reactive power...... are used as load basics for the analysis. In term of PV genera-tion profiles, a realistic PV output power is assumed. Four relevant indicies such as phase neutral voltage, netural potential voltage, unbalanced factor (VUF), and power losses are evaluated in the present study. The simulation tests include...

  8. Can undersea voltage measurements detect tsunamis?

    Digital Repository Service at National Institute of Oceanography (India)

    Manoj, C.; Kuvshinov, A.; Neetu, S.; Harinarayana, T.

    The movement of electrically conducting ocean water in the ambient geomagnetic field induces secondary electric and magnetic fields in the oceans. Ocean water transport is now routinely inferred from undersea cable voltage data. We try to answer...

  9. Low voltage arc formation in railguns

    Science.gov (United States)

    Hawke, Ronald S.

    1987-01-01

    A low voltage plasma arc is first established across the rails behind the projectile by switching a low voltage high current source across the rails to establish a plasma arc by vaporizing a fuse mounted on the back of the projectile, maintaining the voltage across the rails below the railgun breakdown voltage to prevent arc formation ahead of the projectile. After the plasma arc has been formed behind the projectile a discriminator switches the full energy bank across the rails to accelerate the projectile. A gas gun injector may be utilized to inject a projectile into the breech of a railgun. The invention permits the use of a gas gun or gun powder injector and an evacuated barrel without the risk of spurious arc formation in front of the projectile.

  10. Induced voltage in an open wire

    CERN Document Server

    Morawetz, K; Trupp, A

    2015-01-01

    A puzzle arising from Faraday's law is considered and solved concerning the question which voltage is induced in an open wire feeling a time-varying homogeneous magnetic field. The longitudinal electric field contributes 1/3 and the transverse field 2/3 to the induced voltage. The representation of a homogeneous and time-varying magnetic field implies unavoidably a certain symmetry point or line dependent on the geometry of the source. As a consequence the induced voltage of an open wire is found to be the area covered with respect to the symmetry line or point perpendicular to the magnetic field. This in turn allows to find the symmetry points of a magnetic field source by measuring the voltage of an open wire. We present two exactly solvable models for a symmetry point and for a symmetry line. The results are applicable to open circuit problems and for astrophysical applications.

  11. High voltage and electrical insulation engineering

    CERN Document Server

    Arora, Ravindra

    2011-01-01

    "The book is written for students as well as for teachers and researchers in the field of High Voltage and Insulation Engineering. It is based on the advance level courses conducted at TU Dresden, Germany and Indian Institute of Technology Kanpur, India. The book has a novel approach describing the fundamental concept of field dependent behavior of dielectrics subjected to high voltage. There is no other book in the field of high voltage engineering following this new approach in describing the behavior of dielectrics. The contents begin with the description of fundamental terminology in the subject of high voltage engineering. It is followed by the classification of electric fields and the techniques of field estimation. Performance of gaseous, liquid and solid dielectrics under different field conditions is described in the subsequent chapters. Separate chapters on vacuum as insulation and the lightning phenomenon are included"--

  12. Combined Digital Electronic Current and Voltage Transducer

    Institute of Scientific and Technical Information of China (English)

    段雄英; 邹积岩; 等

    2002-01-01

    A high-performance current and voltage measurement system has been developed in power system.The system is composed of two parts:one current measurement element and one voltage measurement element.A Rogowski coil and a capacitive voltage divider are used respectively for the line current and voltage measurements.Active electronic components are used to modulate signal,and power supply for these components is drawn from power line via an auxiliary current transformer,Measurement signal is transmitted y optical fibers,which is resistant to electromagnetic induction and noise,With careful design and the use of digital signal processing technology,the whole system can meet 0.5% accuracy for metering and provides large dynamic range coupled with good accuracy for protective relaying use.

  13. Compact, Lightweight, High Voltage Propellant Isolators Project

    Data.gov (United States)

    National Aeronautics and Space Administration — TA&T, Inc. proposes an enabling fabrication process for high voltage isolators required in high power solar electric and nuclear electric propulsion (SEP and...

  14. Compact, Lightweight, High Voltage Propellant Isolators Project

    Data.gov (United States)

    National Aeronautics and Space Administration — TA&T, Inc. proposes an enabling fabrication process for high voltage isolators required in high power solar electric and nuclear electric propulsion (SEP and...

  15. Voltage regulation of connexin channel conductance.

    Science.gov (United States)

    Oh, Seunghoon; Bargiello, Thaddeus A

    2015-01-01

    Voltage is an important parameter that regulates the conductance of both intercellular and plasma membrane channels (undocked hemichannels) formed by the 21 members of the mammalian connexin gene family. Connexin channels display two forms of voltage-dependence, rectification of ionic currents and voltage-dependent gating. Ionic rectification results either from asymmetries in the distribution of fixed charges due to heterotypic pairing of different hemichannels, or by channel block, arising from differences in the concentrations of divalent cations on opposite sides of the junctional plaque. This rectification likely underpins the electrical rectification observed in some electrical synapses. Both intercellular and undocked hemichannels also display two distinct forms of voltage-dependent gating, termed Vj (fast)-gating and loop (slow)-gating. This review summarizes our current understanding of the molecular determinants and mechanisms underlying these conformational changes derived from experimental, molecular-genetic, structural, and computational approaches.

  16. The Role of Corticostriatal Systems in Speech Category Learning.

    Science.gov (United States)

    Yi, Han-Gyol; Maddox, W Todd; Mumford, Jeanette A; Chandrasekaran, Bharath

    2016-04-01

    One of the most difficult category learning problems for humans is learning nonnative speech categories. While feedback-based category training can enhance speech learning, the mechanisms underlying these benefits are unclear. In this functional magnetic resonance imaging study, we investigated neural and computational mechanisms underlying feedback-dependent speech category learning in adults. Positive feedback activated a large corticostriatal network including the dorsolateral prefrontal cortex, inferior parietal lobule, middle temporal gyrus, caudate, putamen, and the ventral striatum. Successful learning was contingent upon the activity of domain-general category learning systems: the fast-learning reflective system, involving the dorsolateral prefrontal cortex that develops and tests explicit rules based on the feedback content, and the slow-learning reflexive system, involving the putamen in which the stimuli are implicitly associated with category responses based on the reward value in feedback. Computational modeling of response strategies revealed significant use of reflective strategies early in training and greater use of reflexive strategies later in training. Reflexive strategy use was associated with increased activation in the putamen. Our results demonstrate a critical role for the reflexive corticostriatal learning system as a function of response strategy and proficiency during speech category learning.

  17. Fragment-based learning of visual object categories.

    Science.gov (United States)

    Hegdé, Jay; Bart, Evgeniy; Kersten, Daniel

    2008-04-22

    When we perceive a visual object, we implicitly or explicitly associate it with a category we know. It is known that the visual system can use local, informative image fragments of a given object, rather than the whole object, to classify it into a familiar category. How we acquire informative fragments has remained unclear. Here, we show that human observers acquire informative fragments during the initial learning of categories. We created new, but naturalistic, classes of visual objects by using a novel "virtual phylogenesis" (VP) algorithm that simulates key aspects of how biological categories evolve. Subjects were trained to distinguish two of these classes by using whole exemplar objects, not fragments. We hypothesized that if the visual system learns informative object fragments during category learning, then subjects must be able to perform the newly learned categorization by using only the fragments as opposed to whole objects. We found that subjects were able to successfully perform the classification task by using each of the informative fragments by itself, but not by using any of the comparable, but uninformative, fragments. Our results not only reveal that novel categories can be learned by discovering informative fragments but also introduce and illustrate the use of VP as a versatile tool for category-learning research.

  18. Voltage, Temperature, Frequency Margin Test Report

    DEFF Research Database (Denmark)

    Denver, Troelz

    1999-01-01

    The purpose of the tests is to establish the camera functionality when it is exposed to an extreme environment for prolonged periods, thus simulating the end of life performance. This environment covers temperature, input clock frequency and supply voltage variation......The purpose of the tests is to establish the camera functionality when it is exposed to an extreme environment for prolonged periods, thus simulating the end of life performance. This environment covers temperature, input clock frequency and supply voltage variation...

  19. Joint voltages resulting from lightning currents.

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, William Arthur; Warne, Larry Kevin; Merewether, Kimball O.; Chen, Kenneth C.

    2007-03-01

    Simple formulas are given for the interior voltages appearing across bolted joints from exterior lightning currents. External slot and bolt inductances as well as internal slot and bolt diffusion effects are included. Both linear and ferromagnetic wall materials are considered. A useful simplification of the slot current distribution into linear stripline and cylindrical parts (near the bolts) allows the nonlinear voltages to be estimated in closed form.

  20. Voltage Mode-to-Current Mode Transformation

    Directory of Open Access Journals (Sweden)

    Tejmal S. Rathore

    2012-10-01

    Full Text Available This paper proposes a procedure for converting a class of Op Amp-, FTFN-, CC- and CFAbased voltage mode circuits to corresponding current mode circuits without requiring any additional circuit elements and finally from Op Amp-based voltage mode circuits to any of the FTFN, CC and CFA current mode circuits. The latter circuits perform better at high frequency than the former ones. The validity of the transformation has been checked on simulated circuits with PSPICE.

  1. Low-Voltage Hall Thruster Mode Transitions

    Science.gov (United States)

    2014-06-01

    Technical Paper 3. DATES COVERED (From - To) June 2014- July 2014 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER In-House Low-Voltage Hall Thruster Mode...ABSTRACT Past investigations of the 6kW-class H6 Hall thruster during low-voltage operation revealed two operating modes, corresponding to the...topologies were characterized for the H6 Hall thruster from 100V to 200V discharge, with variation in cathode flow fraction, cathode position inside and

  2. Modular high voltage power supply for chemical analysis

    Science.gov (United States)

    Stamps, James F.; Yee, Daniel D.

    2008-07-15

    A high voltage power supply for use in a system such as a microfluidics system, uses a DC-DC converter in parallel with a voltage-controlled resistor. A feedback circuit provides a control signal for the DC-DC converter and voltage-controlled resistor so as to regulate the output voltage of the high voltage power supply, as well as, to sink or source current from the high voltage supply.

  3. Wind Power Plant Voltage Stability Evaluation: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Muljadi, E.; Zhang, Y. C.

    2014-09-01

    Voltage stability refers to the ability of a power system to maintain steady voltages at all buses in the system after being subjected to a disturbance from a given initial operating condition. Voltage stability depends on a power system's ability to maintain and/or restore equilibrium between load demand and supply. Instability that may result occurs in the form of a progressive fall or rise of voltages of some buses. Possible outcomes of voltage instability are the loss of load in an area or tripped transmission lines and other elements by their protective systems, which may lead to cascading outages. The loss of synchronism of some generators may result from these outages or from operating conditions that violate a synchronous generator's field current limit, or in the case of variable speed wind turbine generator, the current limits of power switches. This paper investigates the impact of wind power plants on power system voltage stability by using synchrophasor measurements.

  4. Cryocooled Josephson standards for AC voltage metrology

    Science.gov (United States)

    Durandetto, P.; Sosso, A.; Monticone, E.; Trinchera, B.; Fretto, M.; Lacquaniti, V.

    2017-05-01

    The Josephson effect is worldwide used as a basis for constant reference voltages in national metrological institutes and in calibration laboratories of industry. Research on Josephson voltage standards is aiming at a fundamental change also in the metrology of the volt for AC and arbitrary waveforms: programmable Josephson voltage standards converting a digital code into a quantum-accurate stepwise waveform are already available in primary laboratories and even more advanced standards for converting sub-nanosecond binary coded pulses into any arbitrary signal with quantum accuracy are now actively developed and tested. A new experimental setup based on a two-stage Gifford-McMahon cryocooler has been developed at INRiM for the operation of AC-Josephson voltage standards. Among its distinct features, the possibility of employing both the aforementioned techniques (programmable and pulsed Josephson voltage standards) is particularly interesting. Quantum-based AC voltage sine waves have been synthesized with both programmable and pulse-driven arrays, although their accuracy is still limited by thermal oscillations due to the cryocooler piston motion.

  5. SIMULATION OF INTERLINE DYNAMIC VOLTAGE RESTORER

    Directory of Open Access Journals (Sweden)

    J.Singaravelan

    2011-08-01

    Full Text Available This paper presents a new approach for the dynamic control of a current source inverter (CSI using Super Conductive Magnetic energy storage (SMES based Interline DVR. The dynamic voltage restorer (DVR provides a technically advanced and economical solution to voltage-sag problem. As the voltage-restoration process involves the real-power injection into the distribution system, the capability ofa DVR, especially for compensating long-duration voltage sags, it depends on the energy storage capacity of the DVR. The interline DVR proposed in this paper provides a way to replenish Dc-link energy storage dynamically. The IDVR consists of several DVRs connected to different distribution feeders in the power system. The DVRs in the IDVR system shares the common energy storage. When one of the DVRcompensates for voltage sag appearing in that feeder, the other DVRs replenish the energy in the common dc-link dynamically. Thus, one DVR in the IDVR system works in voltage-sag compensation mode whilethe other DVRs in the IDVR system operate in power-flow control mode. The proposed topology is simulated using Matlab/Simulink and total IDVR system is simulated using Matlab/Simulink.

  6. Improving transition voltage spectroscopy of molecular junctions

    Science.gov (United States)

    Markussen, Troels; Chen, Jingzhe; Thygesen, Kristian S.

    2011-04-01

    Transition voltage spectroscopy (TVS) is a promising spectroscopic tool for molecular junctions. The principles in TVS is to find the minimum on a Fowler-Nordheim plot where ln(I/V2) is plotted against 1/V and relate the voltage at the minimum Vmin to the closest molecular level. Importantly, Vmin is approximately half the voltage required to see a peak in the dI/dV curve. Information about the molecular level position can thus be obtained at relatively low voltages. In this work we show that the molecular level position can be determined at even lower voltages, Vmin(α), by finding the minimum of ln(I/Vα) with α<2. On the basis of a simple Lorentzian transmission model we analyze theoretical ab initio as well as experimental I-V curves and show that the voltage required to determine the molecular levels can be reduced by ~30% as compared to conventional TVS. As for conventional TVS, the symmetry/asymmetry of the molecular junction needs to be taken into account in order to gain quantitative information. We show that the degree of asymmetry may be estimated from a plot of Vmin(α) vs α.

  7. Large Capacity SMES for Voltage Dip Compensation

    Science.gov (United States)

    Iwatani, Yu; Saito, Fusao; Ito, Toshinobu; Shimada, Mamoru; Ishida, Satoshi; Shimanuki, Yoshio

    Voltage dips of power grids due to thunderbolts, snow damage, and so on, cause serious damage to production lines of precision instruments, for example, semiconductors. In recent years, in order to solve this problem, uninterruptible power supply systems (UPS) are used. UPS, however, has small capacity, so a great number of UPS are needed in large factories. Therefore, we have manufactured the superconducting magnetic energy storage (SMES) system for voltage dip compensation able to protect loads with large capacity collectively. SMES has advantages such as space conservation, long lifetime and others. In field tests, cooperating with CHUBU Electric Power Co., Inc. we proved that SMES is valuable for compensating voltage dips. Since 2007, 10MVA SMES improved from field test machines has been running in a domestic liquid crystal display plant, and in 2008, it protected plant loads from a number of voltage dips. In this paper, we report the action principle and components of the improved SMES for voltage dip compensation, and examples of waveforms when 10MVA SMES compensated voltage dips.

  8. Experimental validation of prototype high voltage bushing

    Science.gov (United States)

    Shah, Sejal; Tyagi, H.; Sharma, D.; Parmar, D.; M. N., Vishnudev; Joshi, K.; Patel, K.; Yadav, A.; Patel, R.; Bandyopadhyay, M.; Rotti, C.; Chakraborty, A.

    2017-08-01

    Prototype High voltage bushing (PHVB) is a scaled down configuration of DNB High Voltage Bushing (HVB) of ITER. It is designed for operation at 50 kV DC to ensure operational performance and thereby confirming the design configuration of DNB HVB. Two concentric insulators viz. Ceramic and Fiber reinforced polymer (FRP) rings are used as double layered vacuum boundary for 50 kV isolation between grounded and high voltage flanges. Stress shields are designed for smooth electric field distribution. During ceramic to Kovar brazing, spilling cannot be controlled which may lead to high localized electrostatic stress. To understand spilling phenomenon and precise stress calculation, quantitative analysis was performed using Scanning Electron Microscopy (SEM) of brazed sample and similar configuration modeled while performing the Finite Element (FE) analysis. FE analysis of PHVB is performed to find out electrical stresses on different areas of PHVB and are maintained similar to DNB HV Bushing. With this configuration, the experiment is performed considering ITER like vacuum and electrical parameters. Initial HV test is performed by temporary vacuum sealing arrangements using gaskets/O-rings at both ends in order to achieve desired vacuum and keep the system maintainable. During validation test, 50 kV voltage withstand is performed for one hour. Voltage withstand test for 60 kV DC (20% higher rated voltage) have also been performed without any breakdown. Successful operation of PHVB confirms the design of DNB HV Bushing. In this paper, configuration of PHVB with experimental validation data is presented.

  9. Frobenius morphisms and stable module categories of repetitive algebras

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Let k be the algebraic closure of a finite field F_q and A be a finite dimensional k-algebra with a Frobenius morphism F.In the present paper we establish a relation between the stable module category of the repetitive algebra  of A and that of the repetitive algebra of the fixed-point algebra A~F.As an application,it is shown that the derived category of A~F is equivalent to the subcategory of F-stable objects in the derived category of A when A has a finite global dimension.

  10. Categories of Massless D-Branes and del Pezzo Surfaces

    CERN Document Server

    Addington, Nicolas

    2013-01-01

    In analogy with the physical concept of a massless D-brane, we define a notion of "Q-masslessness" for objects in the derived category. This is defined in terms of monodromy around singularities in the stringy Kahler moduli space and is relatively easy to study using spherical functors. We consider several examples in which del Pezzo surfaces and other rational surfaces in Calabi-Yau threefolds are contracted. For precisely the del Pezzo surfaces that can be written as hypersurfaces in weighted P3, the category of Q-massless objects is a "fractional Calabi-Yau" category of graded matrix factorizations.

  11. Multifunction Voltage-Mode Filter Using Single Voltage Differencing Differential Difference Amplifier

    Directory of Open Access Journals (Sweden)

    Chaichana Amornchai

    2017-01-01

    Full Text Available In this paper, a voltage mode multifunction filter based on single voltage differencing differential difference amplifier (VDDDA is presented. The proposed filter with three input voltages and single output voltage is constructed with single VDDDA, two capacitors and two resistors. Its quality factor can be adjusted without affecting natural frequency. Also, the natural frequency can be electronically tuned via adjusting of bias current. The filter can offer five output responses, high-pas (HP, band-pass (BP, band-reject (BR, low-pass (LP and all-ass (AP functions in the same circuit topology. The output response can be selected by choosing the suitable input voltage without the component matching condition and the requirement of additional double gain voltage amplifier. PSpice simulation results to confirm an operation of the proposed filter correspond to the theory.

  12. Program-Controlled High Voltage Module in Active Voltage Dividers(AVD) for MPGD

    CERN Document Server

    Ginting, Muhammad Fadhil

    2016-01-01

    Micro Pattern Gas Detectors (MPGD) applications are rapidly developing and became an important part of upgrades for the LHC detectors. RD51/CERN have worked on Active Voltage Divider (AVD) technology for multistage MPGDs, One of the next developments for the AVD is to design and integrate high voltage module in a single box. The Program-Controlled High Voltage Module, part of one AIDA2020 project, has been successfully designed and developed, and can be integrated in AVD design.

  13. Mitigation of Voltage Dip and Voltage Flickering by Multilevel D-STATCOM

    Directory of Open Access Journals (Sweden)

    M. S. Ballal

    2012-01-01

    Full Text Available The basic power quality problems in the distribution network are voltage sag (dip, voltage flickering, and the service interruptions. STATCOM is a Flexible AC Transmission Systems (FACTS technology device which can independently control the flow of reactive power. This paper presents the simulation and analysis of a STATCOM for voltage dip and voltage flickering mitigation. Simulations are carried out in MATLAB/Simulink to validate the performance of the STATCOM. A comparison between the six-pulse inverter and the five-level diode-clamped inverter is carried out for the performance of 66/11 KV distribution system.

  14. Engineering of a Genetically Encodable Fluorescent Voltage Sensor Exploiting Fast Ci-VSP Voltage-Sensing Movements

    OpenAIRE

    Alicia Lundby; Hiroki Mutoh; Dimitar Dimitrov; Walther Akemann; Thomas Knöpfel

    2008-01-01

    Ci-VSP contains a voltage-sensing domain (VSD) homologous to that of voltage-gated potassium channels. Using charge displacement ('gating' current) measurements we show that voltage-sensing movements of this VSD can occur within 1 ms in mammalian membranes. Our analysis lead to development of a genetically encodable fluorescent protein voltage sensor (VSFP) in which the fast, voltage-dependent conformational changes of the Ci-VSP voltage sensor are transduced to similarly fast fluorescence re...

  15. Voltage scheduling for low power/energy

    Science.gov (United States)

    Manzak, Ali

    2001-07-01

    Power considerations have become an increasingly dominant factor in the design of both portable and desk-top systems. An effective way to reduce power consumption is to lower the supply voltage since voltage is quadratically related to power. This dissertation considers the problem of lowering the supply voltage at (i) the system level and at (ii) the behavioral level. At the system level, the voltage of the variable voltage processor is dynamically changed with the work load. Processors with limited sized buffers as well as those with very large buffers are considered. Given the task arrival times, deadline times, execution times, periods and switching activities, task scheduling algorithms that minimize energy or peak power are developed for the processors equipped with very large buffers. A relation between the operating voltages of the tasks for minimum energy/power is determined using the Lagrange multiplier method, and an iterative algorithm that utilizes this relation is developed. Experimental results show that the voltage assignment obtained by the proposed algorithm is very close (0.1% error) to that of the optimal energy assignment and the optimal peak power (1% error) assignment. Next, on-line and off-fine minimum energy task scheduling algorithms are developed for processors with limited sized buffers. These algorithms have polynomial time complexity and present optimal (off-line) and close-to-optimal (on-line) solutions. A procedure to calculate the minimum buffer size given information about the size of the task (maximum, minimum), execution time (best case, worst case) and deadlines is also presented. At the behavioral level, resources operating at multiple voltages are used to minimize power while maintaining the throughput. Such a scheme has the advantage of allowing modules on the critical paths to be assigned to the highest voltage levels (thus meeting the required timing constraints) while allowing modules on non-critical paths to be assigned

  16. Categorial Subsystem Independence as Morphism Co-possibility

    Science.gov (United States)

    Gyenis, Zalán; Rédei, Miklós

    2017-08-01

    This paper formulates a notion of independence of subobjects of an object in a general (i.e., not necessarily concrete) category. Subobject independence is the categorial generalization of what is known as subsystem independence in the context of algebraic relativistic quantum field theory. The content of subobject independence formulated in this paper is morphism co-possibility: two subobjects of an object will be defined to be independent if any two morphisms on the two subobjects of an object are jointly implementable by a single morphism on the larger object. The paper investigates features of subobject independence in general, and subobject independence in the category of C*-algebras with respect to operations (completely positive unit preserving linear maps on C*-algebras) as morphisms is suggested as a natural subsystem independence axiom to express relativistic locality of the covariant functor in the categorial approach to quantum field theory.

  17. Solving the Selective Multi-Category Parallel-Servicing Problem

    DEFF Research Database (Denmark)

    Range, Troels Martin; Lusby, Richard Martin; Larsen, Jesper

    In this paper we present a new scheduling problem and describe a shortest path based heuristic as well as a dynamic programming based exact optimization algorithm to solve it. The Selective Multi-Category Parallel-Servicing Problem (SMCPSP) arises when a set of jobs has to be scheduled on a server...... (machine) with limited capacity. Each job requests service in a prespecified time window and belongs to a certain category. Jobs may be serviced partially, incurring a penalty; however, only jobs of the same category can be processed simultaneously. One must identify the best subset of jobs to process...... in each time interval of a given planning horizon while respecting the server capacity and scheduling requirements. We compare the proposed solution methods with a MILP formulation and show that the dynamic programming approach is faster when the number of categories is large, whereas the MILP can...

  18. Solving the selective multi-category parallel-servicing problem

    DEFF Research Database (Denmark)

    Range, Troels Martin; Lusby, Richard Martin; Larsen, Jesper

    2015-01-01

    In this paper, we present a new scheduling problem and describe a shortest path-based heuristic as well as a dynamic programming-based exact optimization algorithm to solve it. The selective multi-category parallel-servicing problem arises when a set of jobs has to be scheduled on a server (machine......) with limited capacity. Each job requests service in a prespecified time window and belongs to a certain category. Jobs may be serviced partially, incurring a penalty; however, only jobs of the same category can be processed simultaneously. One must identify the best subset of jobs to process in each time...... interval of a given planning horizon, while respecting the server capacity and scheduling requirements. We compare the proposed solution methods with a Mixed Integer Linear Programming (MILP) formulation and show that the dynamic programming approach is faster when the number of categories is large...

  19. Normal and abnormal category-effects in visual object recognition

    DEFF Research Database (Denmark)

    Gerlach, Christian

    2017-01-01

    Are all categories of objects recognized in the same manner visually? Evidence from neuropsychology suggests they are not, as some brain injured patients are more impaired in recognizing natural objects than artefacts while others show the opposite impairment. In an attempt to explain category......-specific deficits for natural objects Glyn Humphreys and colleagues suggested that natural objects are harder to perceptually differentiate than artefacts because natural objects are more structurally similar than artefacts. This explanation was proposed in the context of the Cascade model of visual object naming....... While this model has been successful in accounting for a number of observations concerning category-specificity in both patients with brain injury and normal subjects, it has also become clear that there are many important aspects of category-specificity that the model cannot accommodate...

  20. 33 CFR 151.39 - Operating requirements: Category D NLS.

    Science.gov (United States)

    2010-07-01

    ... Protection to the Antarctic Treaty as it Pertains to Pollution from Ships Noxious Liquid Substance Pollution... for the operation of oceangoing ships carrying Category D NLSs in 46 CFR 153.901, 153.909,...

  1. Category theoretic analysis of single-photon decision maker

    CERN Document Server

    Kim, Makoto Naruse Song-Ju; Berthel, Martin; Drezet, Aurélien; Huant, Serge; Hori, Hirokazu

    2016-01-01

    Decision making is a vital function in the era of artificial intelligence; however, its physical realizations and their theoretical fundamentals are not yet known. In our former study [Sci. Rep. 5, 513253 (2015)], we demonstrated that single photons can be used to make decisions in uncertain, dynamically changing environments. The multi-armed bandit problem was successfully solved using the dual probabilistic and particle attributes of single photons. Herein, we present the category theoretic foundation of the single-photon-based decision making, including quantitative analysis that agrees well with the experimental results. The category theoretic model unveils complex interdependencies of the entities of the subject matter in the most simplified manner, including a dynamically changing environment. In particular, the octahedral structure in triangulated categories provides a clear understanding of the underlying mechanisms of the single-photon decision maker. This is the first demonstration of a category the...

  2. A Study on three categories of college students' FLA

    Institute of Scientific and Technical Information of China (English)

    Bi Ran

    2015-01-01

    The paper is concerned with an empirical study on three categories of college students' FLA. The aim is to enhance the efficiency of college English teaching and help students to improve English level.

  3. Goguen categories a categorical approach to l-fuzzy relations

    CERN Document Server

    Winter, Michael; Mundici, Daniele

    2007-01-01

    Goguen categories extend the relational calculus and its categorical formalization to the fuzzy world. Starting from the fundamental concepts of sets, binary relations and lattices this book introduces several categorical formulations of an abstract theory of relations such as allegories, Dedekind categories and related structures. It is shown that neither theory is sufficiently rich to describe basic operations on fuzzy relations. The book then introduces Goguen categories and provides a comprehensive study of these structures including their representation theory, and the definability of norm-based operations. The power of the theory is demonstrated by a comprehensive example. A certain Goguen category is used to specify and to develop a fuzzy controller. Based on its abstract description as well as certain desirable properties and their formal proofs, a verified controller is derived without compromising the - sometimes - intuitive choice of norm-based operations by fuzzy engineers.

  4. A functional categoriality of adjec- tives in Chichewa and Chiyao*

    African Journals Online (AJOL)

    tion and occur within the noun phrase. Second, forms for ... Although formal linguistics treats the relations of adjectives and the nouns or noun phrases they qualify as ..... A discourse approach to the crossclinguistic category. 'adjective'. In John ...

  5. Category 3 threshold quantities for hazard categorization of nonreactor facilities

    Energy Technology Data Exchange (ETDEWEB)

    Mandigo, R.L.

    1996-02-13

    This document provides the information necessary to determine Hazard Category 3 threshold quantities for those isotopes of interest not listed in WHC-CM-4-46, Section 4, Table 1.''Threshold Quantities.''

  6. Solving the selective multi-category parallel-servicing problem

    DEFF Research Database (Denmark)

    Range, Troels Martin; Lusby, Richard Martin; Larsen, Jesper

    2015-01-01

    In this paper, we present a new scheduling problem and describe a shortest path-based heuristic as well as a dynamic programming-based exact optimization algorithm to solve it. The selective multi-category parallel-servicing problem arises when a set of jobs has to be scheduled on a server (machine......) with limited capacity. Each job requests service in a prespecified time window and belongs to a certain category. Jobs may be serviced partially, incurring a penalty; however, only jobs of the same category can be processed simultaneously. One must identify the best subset of jobs to process in each time...... interval of a given planning horizon, while respecting the server capacity and scheduling requirements. We compare the proposed solution methods with a Mixed Integer Linear Programming (MILP) formulation and show that the dynamic programming approach is faster when the number of categories is large...

  7. Non-unitary fusion categories and their doubles via endomorphisms

    CERN Document Server

    Evans, David E

    2015-01-01

    We realise non-unitary fusion categories using subfactor-like methods, and compute their quantum doubles and modular data. For concreteness we focus on generalising the Haagerup-Izumi family of Q-systems. For example, we construct endomorphism realisations of the (non-unitary) Yang-Lee model, and non-unitary analogues of one of the even subsystems of the Haagerup subfactor and of the Grossman-Snyder system. We supplement Izumi's equations for identifying the half-braidings, which were incomplete even in his Q-system setting. We conjecture a remarkably simple form for the modular S and T matrices of the doubles of these fusion categories. We would expect all of these doubles to be realised as the category of modules of a rational VOA and conformal net of factors. We expect our approach will also suffice to realise the non-semisimple tensor categories arising in logarithmic conformal field theories.

  8. LexGram - a practical categorial grammar formalism -

    OpenAIRE

    1995-01-01

    We present the LexGram system, an amalgam of (Lambek) categorial grammar and Head Driven Phrase Structure Grammar (HPSG), and show that the grammar formalism it implements is a well-structured and useful tool for actual grammar development.

  9. Organized simultaneous displays facilitate learning of complex natural science categories.

    Science.gov (United States)

    Meagher, Brian J; Carvalho, Paulo F; Goldstone, Robert L; Nosofsky, Robert M

    2017-02-24

    Subjects learned to classify images of rocks into the categories igneous, metamorphic, and sedimentary. In accord with the real-world structure of these categories, the to-be-classified rocks in the experiments had a dispersed similarity structure. Our central hypothesis was that learning of these complex categories would be improved through observational study of organized, simultaneous displays of the multiple rock tokens. In support of this hypothesis, a technique that included the presentation of the simultaneous displays during phases of the learning process yielded improved acquisition (Experiment 1) and generalization (Experiment 2) compared to methods that relied solely on sequential forms of study and testing. The technique appears to provide a good starting point for application of cognitive-psychology principles of effective category learning to the science classroom.

  10. Building Bridges Between Scientific Categories and Common Sense Social Representations

    Science.gov (United States)

    Kleiman, A.

    2005-05-01

    The teaching of scientific categories in remote regions of the country, far away from research centers involved in the production of knowledge must take into account the layman's common sense concepts of those categories. Our research on the comprehension and learning of linguistic categories in on-service education courses gives support to the utility of the notion of social representations (such as described by Moscovici, Abric and others ) and has shown that re-textualization of scientific definitions undertaken by students in on-service training programs is reinforced by everyday, non-scientific categories. It has also shown that re-textualization is an activity that involves the social representation of the discourse objects. It has been said that all scientific concepts have a a corresponding common sense one; our paper addresses the problem of how to investigate the community's local knowledge so as to build the foundations of outreach programs.

  11. Threat Identification Parameters for a Stolen Category 1 Radioactive Source

    Energy Technology Data Exchange (ETDEWEB)

    Ussery, Larry Eugene [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Winkler, Ryan [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Myers, Steven Charles [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-02-18

    Radioactive sources are used very widely for research and practical applications across medicine, industry, government, universities, and agriculture. The risks associated with these sources vary widely depending on the specific radionuclide used to make the source, source activity, and its chemical and physical form. Sources are categorized by a variety of classification schemes according to the specific risk they pose to the public. This report specifically addresses sources that are classified in the highest category for health risk (category 1). Exposure to an unshielded or lightly shielded category 1 source is extremely dangerous to life and health and can be fatal in relatively short exposure times measured in seconds to minutes. A Category 1 source packaged according to the guidelines dictated by the NRC and U.S. Department of Transportation will typically be surrounded by a large amount of dense shielding material, but will still exhibit a significant dose rate in close proximity. Detection ranges for Category 1 gamma ray sources can extend beyond 5000 ft, but will depend mostly on the source isotope and activity, and the level of shielding around the source. Category 1 sources are easy to detect, but difficult to localize. Dose rates in proximity to an unshielded Category 1 source are extraordinarily high. At distances of a few hundred feet, the functionality of many commonly used handheld instruments will be extremely limited for both the localization and identification of the source. Radiation emitted from a Category 1 source will scatter off of both solid material (ground and buildings) and the atmosphere, a phenomenon known as skyshine. This scattering affects the ability to easily localize and find the source.

  12. A data mining framework for targeted category promotions

    OpenAIRE

    Reutterer, Thomas; Hornik, Kurt; March, Nicolas; Gruber, Kathrin

    2016-01-01

    This research presents a new approach to derive recommendations for segment-specific, targeted marketing campaigns on the product category level. The proposed methodological framework serves as a decision support tool for customer relationship managers or direct marketers to select attractive product categories for their target marketing efforts, such as segment-specific rewards in loyalty programs, cross-merchandising activities, targeted direct mailings, customized supplement...

  13. Different BIRADS Categories in Screening and Diagnostic Mammography

    Directory of Open Access Journals (Sweden)

    A. R. Ehsanbakhsh

    2009-11-01

    Full Text Available Background/Objective: Breast cancer is the most common cancer among Iranian women. The mean age of these cancer patients is one decade younger than that of other developing countries. The aim of this study was frequency determination of Breast Imaging Reporting and Data System (BIRADS subcategories, especially, higher categories and analysis of its related factors in the patients referred to the radiology department of Valie-Asr Hospital, Birjand."n"nPatients and Methods: The study was performed on 437 female patients from June 2006 to May 2007. Patients were divided into two groups; namely, those who underwent screening mammography and those who underwent diagnostic mammography. An expert radiologist reported the mammograms according to BIRADS classification. SPSS ver 12 software and Chi-square test were used for statistical analysis and P-value was significant under 0.05. Results: The mean age was 43.8±9 years. Eighty-one percent of the mammograms were diagnostic and only 19% of them were screening mammographies. Unilateral breast pain was the most common symptom (29% of which 68% were premenopausal. Fify-five percent of them had a history of OCP consumption. The overall BIRADS classification frequencies were: category 0: 9 (3%, category 1: 85 (19%, category 2: 268 (61%, category 3: 37 (8%, category 4: 22 (5%, category 5: 16 (4%. A positive test result (BIRADS categories 4 and 5 in our study was 10.7% in the diagnostic group and 1.2% in the screening group (p=0.007. Five percent of all patients had a familial history of breast cancer. Conclusion: Screening mammography is recommended for early evaluation and early diagnosis of breast cancer.     

  14. Solving Orienteering with Category Constraints Using Prioritized Search

    OpenAIRE

    Bolzoni, Paolo; Helmer, Sven

    2017-01-01

    We develop an approach for solving rooted orienteering problems with category constraints as found in tourist trip planning and logistics. It is based on expanding partial solutions in a systematic way, prioritizing promising ones, which reduces the search space we have to traverse during the search. The category constraints help in reducing the space we have to explore even further. We implement an algorithm that computes the optimal solution and also illustrate how our approach can be turne...

  15. Resource alignment in the category management of builders’ merchants

    OpenAIRE

    Ellström, Daniel; Rehme, Jakob

    2016-01-01

    Previous retailer-supplier research reports both positive and negative collaboration outcomes. Resource alignment, or how collaborating actors’ resources affect each other, is a concept that has been brought forward to explain when collaboration increases performance. As the category management of builders’ merchants involves actors with different sets of resources, the resource alignment framework can be used to better understand the outcomes of collaboration in category management. The aim ...

  16. Cochain sequences and the Quillen category of a coclass family

    OpenAIRE

    Eick, Bettina; Green, David J

    2015-01-01

    We introduce the concept of an infinite cochain sequence and initiate a theory of homological algebra for them. We show how these sequences simplify and improve the construction of infinite coclass families (as introduced by Eick and Leedham-Green) and how they apply in proving that almost all groups in such a family have equivalent Quillen categories. We also include some examples of infinite families of p-groups from different coclass families that have equivalent Quillen categories.

  17. On the 3-arrow calculus for homotopy categories

    CERN Document Server

    Thomas, Sebastian

    2010-01-01

    We develop a localisation theory for certain categories, yielding a 3-arrow calculus: Every morphism in the localisation is represented by a diagram of length 3, and two such diagrams represent the same morphism if and only if they can be embedded in a 3-by-3 diagram in an appropriate way. The methods to construct this localisation are similar to the Ore localisation for a 2-arrow calculus; in particular, we do not have to use zigzags of arbitrary length. Applications include the localisation of an arbitrary model category with respect to its weak equivalences as well as the localisation of its full subcategories of cofibrant, fibrant and bifibrant objects, giving the homotopy category in all four cases. In contrast to the approach of Dwyer, Hirschhorn, Kan and Smith, the model category under consideration does not need to admit functorial factorisations. Moreover, our method shows that the derived category of any abelian (or idempotent splitting exact) category admits a 3-arrow calculus if we localise the ca...

  18. Drinfeld Center and Representation Theory for Monoidal Categories

    Science.gov (United States)

    Neshveyev, Sergey; Yamashita, Makoto

    2016-07-01

    Motivated by the relation between the Drinfeld double and central property (T) for quantum groups, given a rigid C*-tensor category {mathcal{C}} and a unitary half-braiding on an ind-object, we construct a *-representation of the fusion algebra of {mathcal{C}}. This allows us to present an alternative approach to recent results of Popa and Vaes, who defined C*-algebras of monoidal categories and introduced property (T) for them. As an example we analyze categories {mathcal{C}} of Hilbert bimodules over a II1-factor. We show that in this case the Drinfeld center is monoidally equivalent to a category of Hilbert bimodules over another II1-factor obtained by the Longo-Rehren construction. As an application, we obtain an alternative proof of the result of Popa and Vaes stating that property (T) for the category defined by an extremal finite index subfactor {N subset M} is equivalent to Popa's property (T) for the corresponding SE-inclusion of II1-factors. In the last part of the paper we study Müger's notion of weakly monoidally Morita equivalent categories and analyze the behavior of our constructions under the equivalence of the corresponding Drinfeld centers established by Schauenburg. In particular, we prove that property (T) is invariant under weak monoidal Morita equivalence.

  19. Investigation of phase-wise voltage regulator control logics for compensating voltage deviations in an experimental low voltage network

    DEFF Research Database (Denmark)

    Hu, Junjie; Zecchino, Antonio; Marinelli, Mattia

    2016-01-01

    either locally or remotely. To evaluate and compare the control performances of the three control logics, all the tests use the same loading profiles. The experimental results indicate that the modified line compensation control can regulate voltage in a safe band in the case of various load......This paper investigates the control logics of an on-load tap-changer (OLTC) transformer by means of an experimental system validation. The experimental low-voltage unbalanced system consists of a decoupled single-phase OLTC transformer, a 75-metre 16 mm2 cable, a controllable single-phase resistive...... load and an electric vehicle, which has the vehicle-to-grid function. Three control logics of the OLTC transformer are described in the study. The three control logics are classified based on their control objectives and control inputs, which include network currents and voltages, and can be measured...

  20. High voltage testing for the MAJORANA DEMONSTRATOR

    Energy Technology Data Exchange (ETDEWEB)

    Abgrall, N. [Nuclear Science Division, Lawrence Berkeley National Laboratory, Berkeley, CA (United States); Arnquist, I.J. [Pacific Northwest National Laboratory, Richland, WA (United States); Avignone, F.T. [Department of Physics and Astronomy, University of South Carolina, Columbia, SC (United States); Oak Ridge National Laboratory, Oak Ridge, TN (United States); Barabash, A.S. [National Research Center “Kurchatov Institute” Institute for Theoretical and Experimental Physics, Moscow (Russian Federation); Bertrand, F.E. [Oak Ridge National Laboratory, Oak Ridge, TN (United States); Bradley, A.W. [Nuclear Science Division, Lawrence Berkeley National Laboratory, Berkeley, CA (United States); Brudanin, V. [Joint Institute for Nuclear Research, Dubna (Russian Federation); Busch, M. [Department of Physics, Duke University, Durham, NC (United States); Triangle Universities Nuclear Laboratory, Durham, NC (United States); Buuck, M. [Center for Experimental Nuclear Physics and Astrophysics, and Department of Physics, University of Washington, Seattle, WA (United States); Byram, D. [Department of Physics, University of South Dakota, Vermillion, SD (United States); Caldwell, A.S. [South Dakota School of Mines and Technology, Rapid City, SD (United States); Chan, Y-D. [Nuclear Science Division, Lawrence Berkeley National Laboratory, Berkeley, CA (United States); Christofferson, C.D. [South Dakota School of Mines and Technology, Rapid City, SD (United States); Chu, P.-H. [Los Alamos National Laboratory, Los Alamos, NM (United States); Cuesta, C., E-mail: ccuesta@uw.edu [Center for Experimental Nuclear Physics and Astrophysics, and Department of Physics, University of Washington, Seattle, WA (United States); Detwiler, J.A.; Doe, P.J. [Center for Experimental Nuclear Physics and Astrophysics, and Department of Physics, University of Washington, Seattle, WA (United States); and others

    2016-07-01

    The MAJORANA Collaboration is constructing the MAJORANA DEMONSTRATOR, an ultra-low background, 44-kg modular high-purity Ge (HPGe) detector array to search for neutrinoless double-beta decay in {sup 76}Ge. The phenomenon of surface micro-discharge induced by high-voltage has been studied in the context of the MAJORANA DEMONSTRATOR. This effect can damage the front-end electronics or mimic detector signals. To ensure the correct performance, every high-voltage cable and feedthrough must be capable of supplying HPGe detector operating voltages as high as 5 kV without exhibiting discharge. R&D measurements were carried out to understand the testing system and determine the optimum design configuration of the high-voltage path, including different improvements of the cable layout and feedthrough flange model selection. Every cable and feedthrough to be used at the MAJORANA DEMONSTRATOR was characterized and the micro-discharge effects during the MAJORANA DEMONSTRATOR commissioning phase were studied. A stable configuration has been achieved, and the cables and connectors can supply HPGe detector operating voltages without exhibiting discharge.

  1. Maximum permissible voltage of YBCO coated conductors

    Science.gov (United States)

    Wen, J.; Lin, B.; Sheng, J.; Xu, J.; Jin, Z.; Hong, Z.; Wang, D.; Zhou, H.; Shen, X.; Shen, C.

    2014-06-01

    Superconducting fault current limiter (SFCL) could reduce short circuit currents in electrical power system. One of the most important thing in developing SFCL is to find out the maximum permissible voltage of each limiting element. The maximum permissible voltage is defined as the maximum voltage per unit length at which the YBCO coated conductors (CC) do not suffer from critical current (Ic) degradation or burnout. In this research, the time of quenching process is changed and voltage is raised until the Ic degradation or burnout happens. YBCO coated conductors test in the experiment are from American superconductor (AMSC) and Shanghai Jiao Tong University (SJTU). Along with the quenching duration increasing, the maximum permissible voltage of CC decreases. When quenching duration is 100 ms, the maximum permissible of SJTU CC, 12 mm AMSC CC and 4 mm AMSC CC are 0.72 V/cm, 0.52 V/cm and 1.2 V/cm respectively. Based on the results of samples, the whole length of CCs used in the design of a SFCL can be determined.

  2. High voltage testing for the MAJORANA DEMONSTRATOR

    Science.gov (United States)

    Abgrall, N.; Arnquist, I. J.; Avignone, F. T.; Barabash, A. S.; Bertrand, F. E.; Bradley, A. W.; Brudanin, V.; Busch, M.; Buuck, M.; Byram, D.; Caldwell, A. S.; Chan, Y.-D.; Christofferson, C. D.; Chu, P.-H.; Cuesta, C.; Detwiler, J. A.; Doe, P. J.; Dunagan, C.; Efremenko, Yu.; Ejiri, H.; Elliott, S. R.; Fu, Z.; Galindo-Uribarri, A.; Giovanetti, G. K.; Goett, J.; Green, M. P.; Gruszko, J.; Guinn, I. S.; Guiseppe, V. E.; Henning, R.; Hoppe, E. W.; Howard, S.; Howe, M. A.; Jasinski, B. R.; Keeter, K. J.; Kidd, M. F.; Konovalov, S. I.; Kouzes, R. T.; LaFerriere, B. D.; Leon, J.; Li, A.; MacMullin, J.; Martin, R. D.; Massarczyk, R.; Meijer, S. J.; Mertens, S.; Orrell, J. L.; O'Shaughnessy, C.; Poon, A. W. P.; Radford, D. C.; Rager, J.; Rielage, K.; Robertson, R. G. H.; Romero-Romero, E.; Shanks, B.; Shirchenko, M.; Snyder, N.; Suriano, A. M.; Tedeschi, D.; Thompson, A.; Ton, K. T.; Trimble, J. E.; Varner, R. L.; Vasilyev, S.; Vetter, K.; Vorren, K.; White, B. R.; Wilkerson, J. F.; Wiseman, C.; Xu, W.; Yakushev, E.; Yu, C.-H.; Yumatov, V.

    2016-07-01

    The MAJORANA Collaboration is constructing the MAJORANA DEMONSTRATOR, an ultra-low background, 44-kg modular high-purity Ge (HPGe) detector array to search for neutrinoless double-beta decay in 76Ge. The phenomenon of surface micro-discharge induced by high-voltage has been studied in the context of the MAJORANA DEMONSTRATOR. This effect can damage the front-end electronics or mimic detector signals. To ensure the correct performance, every high-voltage cable and feedthrough must be capable of supplying HPGe detector operating voltages as high as 5 kV without exhibiting discharge. R&D measurements were carried out to understand the testing system and determine the optimum design configuration of the high-voltage path, including different improvements of the cable layout and feedthrough flange model selection. Every cable and feedthrough to be used at the MAJORANA DEMONSTRATOR was characterized and the micro-discharge effects during the MAJORANA DEMONSTRATOR commissioning phase were studied. A stable configuration has been achieved, and the cables and connectors can supply HPGe detector operating voltages without exhibiting discharge.

  3. High voltage testing for the Majorana Demonstrator

    Energy Technology Data Exchange (ETDEWEB)

    Abgrall, N.; Arnquist, Isaac J.; Avignone, F. T.; Barabash, A.; Bertrand, F.; Bradley, A. W.; Brudanin, V.; Busch, Matthew; Buuck, M.; Byram, D.; Caldwell, A. S.; Chan, Yuen-Dat; Christofferson, C. D.; Chu, Pamela M.; Cuesta, C.; Detwiler, Jason A.; Doe, P. J.; Dunagan, C.; Efremenko, Yuri; Ejiri, H.; Elliott, S. R.; Fu, Z.; Galindo-Uribarri, A.; Giovanetti, G. K.; Goett, J.; Green, M. P.; Gruszko, J.; Guinn, I.; Guiseppe, V. E.; Henning, R.; Hoppe, Eric W.; Howard, S.; Howe, M. A.; Jasinski, B. R.; Keeter, K.; Kidd, M. F.; Konovalov, S.; Kouzes, Richard T.; Laferriere, Brian D.; Leon, Jonathan D.; Li, Alexander D.; MacMullin, J.; Martin, R. D.; Massarcyk, R.; Meijer, S. J.; Mertens, S.; Orrell, John L.; O' Shaughnessy, C.; Poon, Alan W.; Radford, D. C.; Rager, J.; Rielage, Keith; Robertson, R. G. H.; Romero Romo, M.; Shanks, B.; Shirchenko, M.; Snyder, N.; Suriano, Anne-Marie E.; Tedeschi, D.; Thompson, Andrew; Ton, K. T.; Trimble, J. E.; Varner, R. L.; Vasilyev, Sergey; Vetter, Kai; Vorren, Kris R.; White, Brandon R.; Wilkerson, J. F.; Wiseman, C.; Xu, W.; Yakushev, E.; Yu, Chang-Hong; Yumatov, V.

    2016-07-01

    The Majorana Collaboration is constructing theMajorana Demonstrator, an ultra-low background, 44-kg modular high-purity Ge (HPGe) detector array to search for neutrinoless double-beta decay in 76Ge. The phenomenon of surface micro-discharge induced by high-voltage has been studied in the context of theMajorana Demonstrator. This effect can damage the front-end electronics or mimic detector signals. To ensure the correct performance, every high-voltage cable and feedthrough must be capable of supplying HPGe detector operating voltages as high as 5 kV without exhibiting discharge. R&D measurements were carried out to understand the testing system and determine the optimum design configuration of the high-voltage path, including different improvements of the cable layout and feedthrough flange model selection. Every cable and feedthrough to be used at the Majorana Demonstrator was characterized and the micro-discharge effects during theMajorana Demonstrator commissioning phase were studied. A stable configuration has been achieved, and the cables and connectors can supply HPGe detector operating voltages without exhibiting discharge.

  4. Low-Voltage Consumption Coordination for Loss Minimization and Voltage Control

    DEFF Research Database (Denmark)

    Juelsgaard, Morten; Sloth, Christoffer; Wisniewski, Rafal

    2014-01-01

    This work presents a strategy for minimizing active power losses in low-voltage grids, by coordinating the consumption of electric vehicles and power generation from solar panels. We show that minimizing losses, also reduces voltage variations, and illustrate how this may be employed for increasing...... the number of electric vehicles and photovoltaic systems in the grid without violating grid constraints....

  5. Low-power low-voltage superior-order curvature corrected voltage reference

    Science.gov (United States)

    Popa, Cosmin

    2010-06-01

    A complementary metal oxide semiconductor (CMOS) voltage reference with a logarithmic curvature-correction will be presented. The first-order compensation is realised using an original offset voltage follower (OVF) block as a proportional to absolute temperature (PTAT) voltage generator, with the advantages of reducing the silicon area and of increasing accuracy by replacing matched resistors with matched transistors. The new logarithmic curvature-correction technique will be implemented using an asymmetric differential amplifier (ADA) block for compensating the logarithmic temperature dependent term from the first-order compensated voltage reference. In order to increase the circuit accuracy, an original temperature-dependent current generator will be designed for computing the exact type of the implemented curvature-correction. The relatively small complexity of the current squarer allows an important increasing of the circuit accuracy that could be achieved by increasing the current generator complexity. As a result of operating most of the MOS transistors in weak inversion, the original proposed voltage reference could be valuable for low-power applications. The circuit is implemented in 0.35 μm CMOS technology and consumes only 60μA for t = 25°C, being supplied at the minimal supply voltage V DD = 1.75V. The temperature coefficient of the reference voltage is 8.7 ppm/°C, while the line sensitivity is 0.75 mV/V for a supply voltage between 1.75 V and 7 V.

  6. Energy Storage Options for Voltage Support in Low-Voltage Grids with High Penetration of Photovoltaic

    DEFF Research Database (Denmark)

    Marra, Francesco; Tarek Fawzy, Y.; Bülo, Thorsten

    2012-01-01

    The generation of power by photovoltaic (PV) systems is constantly increasing in low-voltage (LV) distribution grids, in line with the European environmental targets. To cope with the effects on grid voltage profiles during high generation and low demand periods, new solutions need to be establis...

  7. Voltage-gated proton (H(v)1) channels, a singular voltage sensing domain.

    Science.gov (United States)

    Castillo, Karen; Pupo, Amaury; Baez-Nieto, David; Contreras, Gustavo F; Morera, Francisco J; Neely, Alan; Latorre, Ramon; Gonzalez, Carlos

    2015-11-14

    The main role of voltage-gated proton channels (Hv1) is to extrude protons from the intracellular milieu when, mediated by different cellular processes, the H(+) concentration increases. Hv1 are exquisitely selective for protons and their structure is homologous to the voltage sensing domain (VSD) of other voltage-gated ion channels like sodium, potassium, and calcium channels. In clear contrast to the classical voltage-dependent channels, Hv1 lacks a pore domain and thus permeation necessarily occurs through the voltage sensing domain. Hv1 channels are activated by depolarizing voltages, and increases in internal proton concentration. It has been proposed that local conformational changes of the transmembrane segment S4, driven by depolarization, trigger the molecular rearrangements that open Hv1. However, it is still unclear how the electromechanical coupling is achieved between the VSD and the potential pore, allowing the proton flux from the intracellular to the extracellular side. Here we provide a revised view of voltage activation in Hv1 channels, offering a comparative scenario with other voltage sensing channels domains.

  8. P Voltage Control of DFIG with Two-Mass-Shaft Turbine Model Under Utility Voltage Disturbance

    Directory of Open Access Journals (Sweden)

    Hengameh Kojooyan Jafari

    2016-06-01

    Full Text Available Doubly fed induction generators as a variable speed induction generators are applied instead of other electric machines in wind power plants to be connected to the grid with flexible controllers. Nowadays one of the most important subjects in wind farms is control of output power delivered to the grid under utility disturbance. In this paper, a doubly-fed induction generator with external rotor resistance and power converters model as an external voltage source having an adjustable phase and amplitude with an ordinary turbine connected to one mass shaft model and also two mass shaft model, is used and controlled by a P voltage controller to control the output active power for typical high and low wind speeds under two conditions of utility disturbance; while time of disturbance is not too long to change the domain of external rotor voltage source and also while time is long and the domain of external rotor voltage decreases.Simulation results show that P voltage controller can control output active power under 27% stator voltage drop down for typical low wind speed and 11% stator voltage drop down for typical high wind speed in long time disturbance while 80% of rotor external voltage domain drops down under short time utility disturbance.

  9. Measurement of a power system nominal voltage, frequency and voltage flicker parameters

    Energy Technology Data Exchange (ETDEWEB)

    Alkandari, A.M. [College of Technological Studies, Electrical Engineering Technology Department, Shwiekh (Kuwait); Soliman, S.A. [Electrical Power and Machines Department, Misr University for Science and Technology, Cairo (Egypt)

    2009-09-15

    We present, in this paper, an approach for identifying the frequency and amplitude of voltage flicker signal that imposed on the nominal voltage signal, as well as the amplitude and frequency of the nominal signal itself. The proposed algorithm performs the estimation in two steps; in the first step the original voltage signal is shifted forward and backward by an integer number of sample, one sample in this paper. The new generated signals from such a shift together with the original one is used to estimate the amplitude of the original signal voltage that composed of the nominal voltage and flicker voltage. The average of this amplitude gives the amplitude of the nominal voltage; this amplitude is subtracted from the original identified signal amplitude to obtain the samples of the flicker voltage. In the second step, the argument of the signal is calculated by simply dividing the magnitude of signal sample with the estimated amplitude in the first step. Calculating the arccosine of the argument, the frequency of the nominal signal as well as the phase angle can be computing using the least error square estimation algorithm. Simulation examples are given within the text to show the features of the proposed approach. (author)

  10. Analysis of Voltage Support by Electric Vehicles and Photovoltaic in a Real Danish Low Voltage Network

    DEFF Research Database (Denmark)

    Knezovic, Katarina; Marinelli, Mattia; Juul Møller, René

    2014-01-01

    of incorporating electric vehicles (EVs) in a low voltage distribution network with high penetration of photovoltaic installations (PVs), and focuses on analysing potential voltage support functions from EVs and PVs. In addition, the paper evaluates the benefits that reactive power control may provide...

  11. A Bayesian model of category-specific emotional brain responses.

    Directory of Open Access Journals (Sweden)

    Tor D Wager

    2015-04-01

    Full Text Available Understanding emotion is critical for a science of healthy and disordered brain function, but the neurophysiological basis of emotional experience is still poorly understood. We analyzed human brain activity patterns from 148 studies of emotion categories (2159 total participants using a novel hierarchical Bayesian model. The model allowed us to classify which of five categories--fear, anger, disgust, sadness, or happiness--is engaged by a study with 66% accuracy (43-86% across categories. Analyses of the activity patterns encoded in the model revealed that each emotion category is associated with unique, prototypical patterns of activity across multiple brain systems including the cortex, thalamus, amygdala, and other structures. The results indicate that emotion categories are not contained within any one region or system, but are represented as configurations across multiple brain networks. The model provides a precise summary of the prototypical patterns for each emotion category, and demonstrates that a sufficient characterization of emotion categories relies on (a differential patterns of involvement in neocortical systems that differ between humans and other species, and (b distinctive patterns of cortical-subcortical interactions. Thus, these findings are incompatible with several contemporary theories of emotion, including those that emphasize emotion-dedicated brain systems and those that propose emotion is localized primarily in subcortical activity. They are consistent with componential and constructionist views, which propose that emotions are differentiated by a combination of perceptual, mnemonic, prospective, and motivational elements. Such brain-based models of emotion provide a foundation for new translational and clinical approaches.

  12. THE EVALUATION OF SOURCES OF KNOWLEDGE UNDERLYING DIFFERENT CONCEPTUAL CATEGORIES

    Directory of Open Access Journals (Sweden)

    Guido eGainotti

    2013-02-01

    Full Text Available According to the embodied cognition theory and to the sensory-motor model of semantic knowledge: (a concepts are represented in the brain in the same format in which they have been constructed by the sensory-motor system and (b various conceptual categories differ for the weight that different kinds of information play in their representation. In our study, we have tried to check the second assumption by asking normal elderly subjects to rate their subjective evaluation of the role that various perceptual, motor and language-mediated sources of knowledge could have in the construction of different semantic categories. Our first aim consisted in rating the influence that different sources of knowledge could have in the representation of animals, plant life and artifact categories, rather than in those of living and non-living beings, as many previous studies on this subject have made. We also tried to check the influence of age and stimulus modality on these evaluations of the ‘sources of knowledge’ underlying different conceptual categories. The influence of age was checked by comparing results obtained on our group of elderly subjects with those obtained in a previous study, conducted with the same methodology on a sample of young students, whereas the influence of stimulus modality was assessed by presenting the stimuli in the verbal modality to 50 subjects and in the pictorial modality to 50 other subjects.The distinction between ‘animals’ and ‘plant life’ within the ‘living’ categories was confirmed bythe analysis of their prevalent sources of knowledge and by a cluster analysis, which allowed to distinguish fruits and vegetables from animals. Furthermore, results of the study showed: (a that the visual modality was considered by our subjects as the main source of knowledge for all the categories taken into account; (b that in biological categories the next more important source of information was represented by other

  13. Incidental learning of sound categories is impaired in developmental dyslexia.

    Science.gov (United States)

    Gabay, Yafit; Holt, Lori L

    2015-12-01

    Developmental dyslexia is commonly thought to arise from specific phonological impairments. However, recent evidence is consistent with the possibility that phonological impairments arise as symptoms of an underlying dysfunction of procedural learning. The nature of the link between impaired procedural learning and phonological dysfunction is unresolved. Motivated by the observation that speech processing involves the acquisition of procedural category knowledge, the present study investigates the possibility that procedural learning impairment may affect phonological processing by interfering with the typical course of phonetic category learning. The present study tests this hypothesis while controlling for linguistic experience and possible speech-specific deficits by comparing auditory category learning across artificial, nonlinguistic sounds among dyslexic adults and matched controls in a specialized first-person shooter videogame that has been shown to engage procedural learning. Nonspeech auditory category learning was assessed online via within-game measures and also with a post-training task involving overt categorization of familiar and novel sound exemplars. Each measure reveals that dyslexic participants do not acquire procedural category knowledge as effectively as age- and cognitive-ability matched controls. This difference cannot be explained by differences in perceptual acuity for the sounds. Moreover, poor nonspeech category learning is associated with slower phonological processing. Whereas phonological processing impairments have been emphasized as the cause of dyslexia, the current results suggest that impaired auditory category learning, general in nature and not specific to speech signals, could contribute to phonological deficits in dyslexia with subsequent negative effects on language acquisition and reading. Implications for the neuro-cognitive mechanisms of developmental dyslexia are discussed.

  14. Incidental Learning of Sound Categories is Impaired in Developmental Dyslexia

    Science.gov (United States)

    Gabay, Yafit; Holt, Lori L.

    2015-01-01

    Developmental dyslexia is commonly thought to arise from specific phonological impairments. However, recent evidence is consistent with the possibility that phonological impairments arise as symptoms of an underlying dysfunction of procedural learning. The nature of the link between impaired procedural learning and phonological dysfunction is unresolved. Motivated by the observation that speech processing involves the acquisition of procedural category knowledge, the present study investigates the possibility that procedural learning impairment may affect phonological processing by interfering with the typical course of phonetic category learning. The present study tests this hypothesis while controlling for linguistic experience and possible speech-specific deficits by comparing auditory category learning across artificial, nonlinguistic sounds among dyslexic adults and matched controls in a specialized first-person shooter videogame that has been shown to engage procedural learning. Nonspeech auditory category learning was assessed online via within-game measures and also with a post-training task involving overt categorization of familiar and novel sound exemplars. Each measure reveals that dyslexic participants do not acquire procedural category knowledge as effectively as age- and cognitive-ability matched controls. This difference cannot be explained by differences in perceptual acuity for the sounds. Moreover, poor nonspeech category learning is associated with slower phonological processing. Whereas phonological processing impairments have been emphasized as the cause of dyslexia, the current results suggest that impaired auditory category learning, general in nature and not specific to speech signals, could contribute to phonological deficits in dyslexia with subsequent negative effects on language acquisition and reading. Implications for the neuro-cognitive mechanisms of developmental dyslexia are discussed. PMID:26409017

  15. 30 CFR 75.804 - Underground high-voltage cables.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Underground high-voltage cables. 75.804 Section... AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Underground High-Voltage Distribution § 75.804 Underground high-voltage cables. (a) Underground high-voltage cables used in resistance...

  16. 46 CFR 129.326 - Dual-voltage generators.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Dual-voltage generators. 129.326 Section 129.326... INSTALLATIONS Power Sources and Distribution Systems § 129.326 Dual-voltage generators. If a dual-voltage generator is installed on an OSV— (a) The neutral of the dual-voltage system must be solidly grounded at...

  17. 30 CFR 77.810 - High-voltage equipment; grounding.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false High-voltage equipment; grounding. 77.810... COAL MINES Surface High-Voltage Distribution § 77.810 High-voltage equipment; grounding. Frames, supporting structures, and enclosures of stationary, portable, or mobile high-voltage equipment shall...

  18. 47 CFR 17.54 - Rated lamp voltage.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 1 2010-10-01 2010-10-01 false Rated lamp voltage. 17.54 Section 17.54... voltage. To insure the necessary lumen output by obstruction lights, the rated voltage of incandescent lamps used shall correspond to be within 3 percent higher than the voltage across the lamp socket...

  19. Note: Galvanic isolated voltage source using a single photodiode.

    Science.gov (United States)

    Stoican, O S

    2010-04-01

    A galvanic isolated voltage source able to provide several volts by using a single photodiode is described. A pulse-modulated laser beam is sent to a photodiode. By using a step-up transformer the amplitude of the variable voltage generated by the photodiode is increased. Adding a rectifier cell the variable voltage is converted back into a dc voltage.

  20. Voltage control in active, intelligent low-voltage distribution networks; Spannungshaltung in aktiven, intelligenten Niederspannungsnetzen

    Energy Technology Data Exchange (ETDEWEB)

    Buelo, Thorsten; Mende, Denis [SMA Solar Technology AG, Niestetal (Germany); Geibel, Dominik [Fraunhofer Institut fuer Windenergie und Energiesystemtechnik (IWES), Kassel (Germany)] [and others

    2012-07-01

    This paper describes approaches for the voltage control in low-voltage distribution networks with a high share of distributed energy resources (DER). Taken into account are devices such as distribution transformers with on-load tap changer (OLTC), photovoltaic-inverters with reactive power capability and electronic voltage controllers (EVC). After a short description regarding voltage control, the devices and selected system concepts as well as the advantages and disadvantages of the different devices are described. Finally, the system-concepts are compared using the example of a real low voltage network, taking into account the possible increase of hosting capacity of the network, curtailing losses and the amount of reactive energy to be provided. (orig.)

  1. Low Voltage Analog Circuit Design Based on the Flipped Voltage Follower

    Directory of Open Access Journals (Sweden)

    Neeraj Yadav

    2012-03-01

    Full Text Available The desire for portability of electronics equipment generated a need for low power system in battery products like hearing aids, implantable cardiac pacemakers, cell phones and hand held multimedia terminals. Low voltage analog circuit design differs considerably from those of high voltage analog circuit design. This paper present the basic cell knows as “flipped voltage follower” for low voltage/ low power operation. The detailed classification of basic topologies derived from the FVF cell is presented and there is a low voltage current mirror based on FVF cell has been presented. All the Circuit has been simulated using Hspice tool 0.18µm CMOS Technology. Different quality factors such as frequency response, power consumption are considered. A compression also made between previous current mirror and new designed current mirror. The layout of the current mirror has been also designed using Cadence tool.

  2. Improving Low Voltage Ride Through Capability of Wind Generators Using Dynamic Voltage Restorer

    Science.gov (United States)

    Sivasankar, Gangatharan; Suresh Kumar, Velu

    2014-08-01

    The increasing wind power integration with power grid has forced the situation to improve the reliability of wind generators for stable operation. One important problem with induction generator based wind farm is its low ride through capability to the grid voltage disturbance. Any disturbance such as voltage dip may cause wind farm outages. Since wind power contribution is in predominant percentage, such outages may lead to stability problem. The proposed strategy is to use dynamic voltage controller (DVR) to compensate the voltage disturbance. The DVR provides the wind generator the ability to remain connected in grid and improve the reliability. The voltage dips due to symmetrical and unsymmetrical faults are considered for analysis. The vector control scheme is employed for fault compensation which uses software phase locked loop scheme and park dq0 transformation technique. Extensive simulation results are included to illustrate the control and operation of DVR.

  3. Voltage and frequency control in the Islanded portion of the CIGRE Low Voltage distribution network

    DEFF Research Database (Denmark)

    Mustafa, Ghullam; Bak, Claus Leth; Buriro, Ehsan Ali

    2017-01-01

    imbalance in the islanded MG. The voltage and the frequency of the islanded MG can be restored to the permissible limits if the desired/exceeded amount of active and reactive power is injected/absorbed by the locally available sources in islanded MG. This paper proposes the control strategy which can...... by providing some ancillary services. The main focus of this paper is about the development of a control system for the islanded MG, the selection of Voltage-Frequency controller for the most suitable DG unit of the Low Voltage test network and the control of voltage and frequency in islanding condition. Under...... compensate the problems of the voltage and the frequency deviations in the islanded MG. The selection of the VF controller for the most suitable DG unit of the LV test network is also presented in this paper and effectiveness of the controllers is verified by presenting simulation results...

  4. A dynamic voltage restorer (DVR) with selective harmonic compensation at medium voltage level

    DEFF Research Database (Denmark)

    Newman, M.J.; Holmes, D.G.; Nielsen, J.G.;

    2005-01-01

    -state power through the DVR, the increased losses, and the low modulation depths at which the scheme must operate to achieve acceptable harmonic compensation performance. This paper presents a selective harmonic feedback control strategy that can be easily added to medium-voltage DVR systems to provide...... be advantageous if the series-connected inverter of a DVR could also be used to compensate for any steady-state load voltage harmonics, since this would increase the power quality "value-added" benefits to the grid system. However, before this can be done, consideration must be given to the control of steady...... voltage harmonic compensation capabilities with minimal effect on the sag compensation performance of the basic DVR. The proposed controller has been experimentally verified on a medium-voltage (10 kV) three-phase DVR prototype under a range of conditions, including distorted supply voltages, nonlinear...

  5. A thermoelectric voltage effect in polyethylene oxide

    CERN Document Server

    Martin, B; Kliem, H

    2003-01-01

    The conductivity of polyethylene oxide (PEO) is described with a three-dimensional hopping model considering electrostatic interactions between the ions. Ions fluctuate over energy-barriers in a multi-well potential. To decide whether positive or negative charges are responsible for this conductivity, the thermoelectric voltage is measured. The samples are embedded between two aluminium-electrodes. The oxide on the interface between the electrodes and the PEO serves as a blocking layer. The temperature of each electrode is controlled by a Peltier element. A temperature step is applied to one electrode by changing the temperature of one of the Peltier elements. Due to this temperature gradient, the mobile charges fluctuate thermally activated from the warmer side to the colder side of the sample. The direction of the measured thermoelectric voltage indicates the type of mobile charges. It is found that positive charges are mobile. Further, it is shown that the absolute value of the thermoelectric voltage depen...

  6. FGMOS Based Voltage-Controlled Grounded Resistor

    Directory of Open Access Journals (Sweden)

    R. Pandey

    2010-09-01

    Full Text Available This paper proposes a new floating gate MOSFET (FGMOS based voltage-controlled grounded resistor. In the proposed circuit FGMOS operating in the ohmic region is linearized by another conventional MOSFET operating in the saturation region. The major advantages of FGMOS based voltage-controlled grounded resistor (FGVCGR are simplicity, low total harmonic distortion (THD, and low power consumption. A simple application of this FGVCGR as a tunable high-pass filter is also suggested. The proposed circuits operate at the supply voltages of +/-0.75 V. The circuits are designed and simulated using SPICE in 0.25-µm CMOS technology. The simulation results of FGVCGR demonstrate a THD of 0.28% for the input signal 0.32 Vpp at 45 kHz, and a maximum power consumption of 254 µW.

  7. Voltage stability, bifurcation parameters and continuation methods

    Energy Technology Data Exchange (ETDEWEB)

    Alvarado, F.L. [Wisconsin Univ., Madison, WI (United States)

    1994-12-31

    This paper considers the importance of the choice of bifurcation parameter in the determination of the voltage stability limit and the maximum power load ability of a system. When the bifurcation parameter is power demand, the two limits are equivalent. However, when other types of load models and bifurcation parameters are considered, the two concepts differ. The continuation method is considered as a method for determination of voltage stability margins. Three variants of the continuation method are described: the continuation parameter is the bifurcation parameter the continuation parameter is initially the bifurcation parameter, but is free to change, and the continuation parameter is a new `arc length` parameter. Implementations of voltage stability software using continuation methods are described. (author) 23 refs., 9 figs.

  8. Semisupervised Community Detection by Voltage Drops

    Directory of Open Access Journals (Sweden)

    Min Ji

    2016-01-01

    Full Text Available Many applications show that semisupervised community detection is one of the important topics and has attracted considerable attention in the study of complex network. In this paper, based on notion of voltage drops and discrete potential theory, a simple and fast semisupervised community detection algorithm is proposed. The label propagation through discrete potential transmission is accomplished by using voltage drops. The complexity of the proposal is OV+E for the sparse network with V vertices and E edges. The obtained voltage value of a vertex can be reflected clearly in the relationship between the vertex and community. The experimental results on four real networks and three benchmarks indicate that the proposed algorithm is effective and flexible. Furthermore, this algorithm is easily applied to graph-based machine learning methods.

  9. Intermediate state trapping of a voltage sensor

    DEFF Research Database (Denmark)

    Lacroix, Jérôme J; Pless, Stephan Alexander; Maragliano, Luca

    2012-01-01

    Voltage sensor domains (VSDs) regulate ion channels and enzymes by undergoing conformational changes depending on membrane electrical signals. The molecular mechanisms underlying the VSD transitions are not fully understood. Here, we show that some mutations of I241 in the S1 segment of the Shaker...... Kv channel positively shift the voltage dependence of the VSD movement and alter the functional coupling between VSD and pore domains. Among the I241 mutants, I241W immobilized the VSD movement during activation and deactivation, approximately halfway between the resting and active states......, and drastically shifted the voltage activation of the ionic conductance. This phenotype, which is consistent with a stabilization of an intermediate VSD conformation by the I241W mutation, was diminished by the charge-conserving R2K mutation but not by the charge-neutralizing R2Q mutation. Interestingly, most...

  10. CNFET Based Voltage Differencing Transconductance Amplifier

    Science.gov (United States)

    Laxya; Prasad, Dinesh; Mainuddin; Islam, S. S.

    2017-08-01

    In CMOS Technology basic Problem mainly includes dopant fluctuation, tunnelling effect and line edge roughness below 45nm technology. Carbon Nanotube based structures is better option for widen the Moore’s law due to its scalability channel electrostatics and higher mobility. In this manuscript we demonstrate an optimum design for linear property of CNTFET based VDTA at 32nm technology node. The proposed circuit consist of VDTA with CNTFET having two voltage input and two current outputs so that it works as voltage and transconductance operation to obtain the high performance. The minimum supply voltages of ±0.9V with 32nm technology mode are used. The CNTFET-VDTA performance is simulated on HSPICE. In this paper CNFET-based VDTA provides better results of DC transfer characteristics as compared with CMOS. All the simulation results are performed on HSPICE.

  11. Planar multijunction high voltage solar cells

    Science.gov (United States)

    Evans, J. C., Jr.; Chai, A. T.; Goradia, C.

    1980-01-01

    Technical considerations, preliminary results, and fabrication details are discussed for a family of high-voltage planar multi-junction (PMJ) solar cells which combine the attractive features of planar cells with conventional or interdigitated back contacts and the vertical multijunction (VMJ) solar cell. The PMJ solar cell is internally divided into many voltage-generating regions, called unit cells, which are internally connected in series. The key to obtaining reasonable performance from this device was the separation of top surface field regions over each active unit cell. Using existing solar cell fabricating methods, output voltages in excess of 20 volts per linear centimeter are possible. Analysis of the new device is complex, and numerous geometries are being studied which should provide substantial benefits in both normal sunlight usage as well as with concentrators.

  12. Comparison of Algorithms for Control of Loads for Voltage Regulation

    DEFF Research Database (Denmark)

    Douglass, Philip James; Han, Xue; You, Shi

    2014-01-01

    Autonomous flexible loads can be utilized to regulate voltag e on low voltage feeders. This paper compares two algorithms for controllin g loads: a simple voltage droop, where load power consumption is a varied in proportio n to RMS voltage; and a normalized relative voltage droop, which modifies...... the simpl e voltage droop by subtracting the mean voltage value at the bus and dividing by the standard deviation. These two controllers are applied to hot water heaters simul ated in a simple residential feeder. The simulation results show that both controllers r educe the frequency of undervoltage events...

  13. Experimental validation of a high voltage pulse measurement method.

    Energy Technology Data Exchange (ETDEWEB)

    Cular, Stefan; Patel, Nishant Bhupendra; Branch, Darren W.

    2013-09-01

    This report describes X-cut lithium niobates (LiNbO3) utilization for voltage sensing by monitoring the acoustic wave propagation changes through LiNbO3 resulting from applied voltage. Direct current (DC), alternating current (AC) and pulsed voltage signals were applied to the crystal. Voltage induced shift in acoustic wave propagation time scaled quadratically for DC and AC voltages and linearly for pulsed voltages. The measured values ranged from 10 - 273 ps and 189 ps 2 ns for DC and non-DC voltages, respectively. Data suggests LiNbO3 has a frequency sensitive response to voltage. If voltage source error is eliminated through physical modeling from the uncertainty budget, the sensors U95 estimated combined uncertainty could decrease to ~0.025% for DC, AC, and pulsed voltage measurements.

  14. High-voltage test and measuring techniques

    CERN Document Server

    Hauschild, Wolfgang

    2014-01-01

    It is the intent of this book to combine high-voltage (HV) engineering with HV testing technique and HV measuring technique. Based on long-term experience gained by the authors as lecturer and researcher as well as member in international organizations, such as IEC and CIGRE, the book will reflect the state of the art as well as the future trends in testing and diagnostics of HV equipment to ensure a reliable generation, transmission and distribution of electrical energy. The book is intended not only for experts but also for students in electrical engineering and high-voltage engineering.

  15. Voltage control of DC islanded microgrids

    DEFF Research Database (Denmark)

    Tucci, Michele; Riverso, Stefano; Quintero, Juan Carlos Vasquez

    2015-01-01

    We propose a new decentralized control scheme for DC Islanded microGrids (ImGs) composed by several Distributed Generation Units (DGUs) with a general interconnection topology. Each local controller regulates to a reference value the voltage of the Point of Common Coupling (PCC) of the correspond......We propose a new decentralized control scheme for DC Islanded microGrids (ImGs) composed by several Distributed Generation Units (DGUs) with a general interconnection topology. Each local controller regulates to a reference value the voltage of the Point of Common Coupling (PCC...

  16. Open-ended category learning for language acquisition

    Science.gov (United States)

    Seabra Lopes, Luis; Chauhan, Aneesh

    2008-12-01

    Motivated by the need to support language-based communication between robots and their human users, as well as grounded symbolic reasoning, this paper presents a learning architecture that can be used by robotic agents for long-term and open-ended category acquisition. To be more adaptive and to improve learning performance as well as memory usage, this learning architecture includes a metacognitive processing component. Multiple object representations and multiple classifiers and classifier combinations are used. At the object level, the main similarity measure is based on a multi-resolution matching algorithm. Categories are represented as sets of known instances. In this instance-based approach, storing and forgetting rules optimise memory usage. Classifier combinations are based on majority voting and the Dempster-Shafer evidence theory. All learning computations are carried out during the normal execution of the agent, which allows continuous monitoring of the performance of the different classifiers. The measured classification successes of the individual classifiers support an attentional selection mechanism, through which classifier combinations are dynamically reconfigured and a specific classifier is chosen to predict the category of a new unseen object. A simple physical agent, incorporating these learning capabilities, is used to test the approach. A long-term experiment was carried out having in mind the open-ended nature of category learning. With the help of a human mediator, the agent incrementally learned 68 categories of real-world objects visually perceivable through an inexpensive camera. Various aspects of the approach are evaluated through systematic experiments.

  17. Metacognitive monitoring during category learning: how success affects future behaviour.

    Science.gov (United States)

    Doyle, Mario E; Hourihan, Kathleen L

    2016-10-01

    The purpose of this study was to see how people perceive their own learning during a category learning task, and whether their perceptions matched their performance. In two experiments, participants were asked to learn natural categories, of both high and low variability, and make category learning judgements (CLJs). Variability was manipulated by varying the number of exemplars and the number of times each exemplar was presented within each category. Experiment 1 showed that participants were generally overconfident in their knowledge of low variability families, suggesting that they considered repetition to be more useful for learning than it actually was. Also, a correct trial, for a particular category, was more likely to occur if the previous trial was correct. CLJs had the largest increase when a trial was correct following an incorrect trial and the largest decrease when an incorrect trial followed a correct trial. Experiment 2 replicated these results, but also demonstrated that global CLJ ratings showed the same bias towards repetition. These results indicate that we generally identify success as being the biggest determinant of learning, but do not always recognise cues, such as variability, that enhance learning.

  18. Using spoken words to guide open-ended category formation.

    Science.gov (United States)

    Chauhan, Aneesh; Seabra Lopes, Luís

    2011-11-01

    Naming is a powerful cognitive tool that facilitates categorization by forming an association between words and their referents. There is evidence in child development literature that strong links exist between early word-learning and conceptual development. A growing view is also emerging that language is a cultural product created and acquired through social interactions. Inspired by these studies, this paper presents a novel learning architecture for category formation and vocabulary acquisition in robots through active interaction with humans. This architecture is open-ended and is capable of acquiring new categories and category names incrementally. The process can be compared to language grounding in children at single-word stage. The robot is embodied with visual and auditory sensors for world perception. A human instructor uses speech to teach the robot the names of the objects present in a visually shared environment. The robot uses its perceptual input to ground these spoken words and dynamically form/organize category descriptions in order to achieve better categorization. To evaluate the learning system at word-learning and category formation tasks, two experiments were conducted using a simple language game involving naming and corrective feedback actions from the human user. The obtained results are presented and discussed in detail.

  19. Dual systems of speech category learning across the lifespan

    Science.gov (United States)

    Maddox, W. Todd; Chandrasekaran, Bharath; Smayda, Kirsten; Yi, Han-Gyol

    2013-01-01

    Although categorization is fundamental to speech processing, little is known about the learning systems that mediate auditory categorization and even less is known about changes across the lifespan. Vision research supports dual-learning systems that are grounded in neuroscience and are partially-dissociable. The reflective, rule-based system is prefrontally mediated and uses working memory and executive attention to develop and test rules for classifying in an explicit fashion. The reflexive, information-integration system is striatally mediated and operates by implicitly associating perception with actions that lead to reinforcement. We examine the extent to which dual-learning systems mediate auditory and speech learning in younger and older adults. We examined auditory category learning when a rule-based strategy (Experiment 1) or information-integration strategy (Experiment 2) was optimal, and found an age-related rule-based deficit, but intact information-integration learning. Experiment 3 examined natural auditory category learning, and found an age-related performance deficit. Computational modeling suggested that this was due to older adults’ persistent reliance on sub-optimal, uni-dimensional strategies when two-dimensional strategies were optimal. Working memory capacity was also found to be associated with improved rule-based and natural auditory category learning, but not information-integration category learning. These results suggest that dual-learning systems are operative in speech category learning across the lifespan, and that performance deficits, when present are due to deficiencies in frontally-mediated, rule-based processes. PMID:24364408

  20. Effect of explicit dimensional instruction on speech category learning.

    Science.gov (United States)

    Chandrasekaran, Bharath; Yi, Han-Gyol; Smayda, Kirsten E; Maddox, W Todd

    2016-02-01

    Learning nonnative speech categories is often considered a challenging task in adulthood. This difficulty is driven by cross-language differences in weighting critical auditory dimensions that differentiate speech categories. For example, previous studies have shown that differentiating Mandarin tonal categories requires attending to dimensions related to pitch height and direction. Relative to native speakers of Mandarin, the pitch direction dimension is underweighted by native English speakers. In the current study, we examined the effect of explicit instructions (dimension instruction) on native English speakers' Mandarin tone category learning within the framework of a dual-learning systems (DLS) model. This model predicts that successful speech category learning is initially mediated by an explicit, reflective learning system that frequently utilizes unidimensional rules, with an eventual switch to a more implicit, reflexive learning system that utilizes multidimensional rules. Participants were explicitly instructed to focus and/or ignore the pitch height dimension, the pitch direction dimension, or were given no explicit prime. Our results show that instruction instructing participants to focus on pitch direction, and instruction diverting attention away from pitch height, resulted in enhanced tone categorization. Computational modeling of participant responses suggested that instruction related to pitch direction led to faster and more frequent use of multidimensional reflexive strategies and enhanced perceptual selectivity along the previously underweighted pitch direction dimension.

  1. Unified Power Quality Conditioner for voltage and current compensation

    OpenAIRE

    P.Annapandi; Dr.M.Rajaram

    2012-01-01

    This paper deals with a Unified Power Quality Conditioner (UPQC) for load balancing, power factorcorrection, voltage regulation, voltage and current harmonics mitigation, mitigation of voltage sag, swelland voltage dip in a three-phase three-wire distribution system for different combinations of linear and nonlinear loads.The unified power quality conditioner (UPQC) is a combination of back to back connected shunt and series active power filters (APFs) to a common DC link voltage, which compe...

  2. Kinship categories across languages reflect general communicative principles.

    Science.gov (United States)

    Kemp, Charles; Regier, Terry

    2012-05-25

    Languages vary in their systems of kinship categories, but the scope of possible variation appears to be constrained. Previous accounts of kin classification have often emphasized constraints that are specific to the domain of kinship and are not derived from general principles. Here, we propose an account that is founded on two domain-general principles: Good systems of categories are simple, and they enable informative communication. We show computationally that kin classification systems in the world's languages achieve a near-optimal trade-off between these two competing principles. We also show that our account explains several specific constraints on kin classification proposed previously. Because the principles of simplicity and informativeness are also relevant to other semantic domains, the trade-off between them may provide a domain-general foundation for variation in category systems across languages.

  3. Quantum field theories on categories fibered in groupoids

    CERN Document Server

    Benini, Marco

    2016-01-01

    We introduce an abstract concept of quantum field theory on categories fibered in groupoids over the category of spacetimes. This provides us with a general and flexible framework to study quantum field theories defined on spacetimes with extra geometric structures such as bundles, connections and spin structures. Using right Kan extensions, we can assign to any such theory an ordinary quantum field theory defined on the category of spacetimes and we shall clarify under which conditions it satisfies the axioms of locally covariant quantum field theory. The same constructions can be performed in a homotopy theoretic framework by using homotopy right Kan extensions, which allows us to obtain first examples of homotopical quantum field theories resembling some aspects of gauge theories.

  4. Modeling Reusable and Interoperable Faceted Browsing Systems with Category Theory.

    Science.gov (United States)

    Harris, Daniel R

    2015-08-01

    Faceted browsing has become ubiquitous with modern digital libraries and online search engines, yet the process is still difficult to abstractly model in a manner that supports the development of interoperable and reusable interfaces. We propose category theory as a theoretical foundation for faceted browsing and demonstrate how the interactive process can be mathematically abstracted. Existing efforts in facet modeling are based upon set theory, formal concept analysis, and lightweight ontologies, but in many regards, they are implementations of faceted browsing rather than a specification of the basic, underlying structures and interactions. We will demonstrate that category theory allows us to specify faceted objects and study the relationships and interactions within a faceted browsing system. Implementations can then be constructed through a category-theoretic lens using these models, allowing abstract comparison and communication that naturally support interoperability and reuse.

  5. Foundations of reusable and interoperable facet models using category theory.

    Science.gov (United States)

    Harris, Daniel R

    2016-10-01

    Faceted browsing has become ubiquitous with modern digital libraries and online search engines, yet the process is still difficult to abstractly model in a manner that supports the development of interoperable and reusable interfaces. We propose category theory as a theoretical foundation for faceted browsing and demonstrate how the interactive process can be mathematically abstracted. Existing efforts in facet modeling are based upon set theory, formal concept analysis, and light-weight ontologies, but in many regards, they are implementations of faceted browsing rather than a specification of the basic, underlying structures and interactions. We will demonstrate that category theory allows us to specify faceted objects and study the relationships and interactions within a faceted browsing system. Resulting implementations can then be constructed through a category-theoretic lens using these models, allowing abstract comparison and communication that naturally support interoperability and reuse.

  6. Parsing Combinatory Categorial Grammar with Answer Set Programming: Preliminary Report

    CERN Document Server

    Lierler, Yuliya

    2011-01-01

    Combinatory categorial grammar (CCG) is a grammar formalism used for natural language parsing. CCG assigns structured lexical categories to words and uses a small set of combinatory rules to combine these categories to parse a sentence. In this work we propose and implement a new approach to CCG parsing that relies on a prominent knowledge representation formalism, answer set programming (ASP) - a declarative programming paradigm. We formulate the task of CCG parsing as a planning problem and use an ASP computational tool to compute solutions that correspond to valid parses. Compared to other approaches, there is no need to implement a specific parsing algorithm using such a declarative method. Our approach aims at producing all semantically distinct parse trees for a given sentence. From this goal, normalization and efficiency issues arise, and we deal with them by combining and extending existing strategies. We have implemented a CCG parsing tool kit - AspCcgTk - that uses ASP as its main computational mean...

  7. Categories of Representations of a Class of Commutative Cancellative Semigroups

    Institute of Scientific and Technical Information of China (English)

    Antonio M. Cegarra; Mario Petrich

    2001-01-01

    A commutative semigroup S is subarchimedean if there exists z ∈ S such that for any a ∈ S, there are n > 0 and x ∈ S such that zn = ax. A commutative cancellative idempotent-free subarchimedean semigroup is a -semigroup.These semigroups admit Tamura-like representations of the form N(G, I) and N(G,ψ), and their groups of quotients Z(G, I) and Z(G, ψ). We consider categories whose objects are of the form (G, I; N), (G, ψ; N), (G, I; Z), and (G, ψ; Z)with suitable morphisms, and establish functorial relationships among these categories as well as with the categories of -semigroups and non-periodic abelian groups.

  8. Fukaya categories of the torus and Dehn surgery.

    Science.gov (United States)

    Lekili, Yanki; Perutz, Timothy

    2011-05-17

    This paper is a companion to the authors' forthcoming work extending Heegaard Floer theory from closed 3-manifolds to compact 3-manifolds with two boundary components via quilted Floer cohomology. We describe the first interesting case of this theory: the invariants of 3-manifolds bounding S(2) [symbol: see text] T(2), regarded as modules over the Fukaya category of the punctured 2-torus. We extract a short proof of exactness of the Dehn surgery triangle in Heegaard Floer homology. We show that A(∞)-structures on the graded algebra A formed by the cohomology of two basic objects in the Fukaya category of the punctured 2-torus are governed by just two parameters (m(6), m(8)), extracted from the Hochschild cohomology of A. For the Fukaya category itself, m(6) ≠ 0.

  9. Evaluation of Bosniak category IIF complex renal cysts

    DEFF Research Database (Denmark)

    Graumann, Ole; Osther, Susanne Sloth; Karstoft, Jens

    2013-01-01

    complex cystic lesions in the kidney (n = 550 in the same number of patients) were reclassified according to the Bosniak classification by two radiologists in consensus. If a patient had more than one lesion, only the highest Bosniak category was recorded. All Bosniak IIF lesions with ≥2-year follow......PURPOSE: To evaluate moderately complex renal cysts of Bosniak category IIF. MATERIALS AND METHODS: The regional ethics committee approved the study. In the period 2003-2009, radiological CT reports of 8,402 CT examinations of the kidneys were analysed retrospectively by one radiologist. All...... nephron-sparing approach to complex renal cysts. TEACHING POINTS : • The Bosniak classification is used to categorise complex renal cystic masses • BIIF cysts behave mostly as benign lesions • Radiological progression in complexity occurs in only 16 % of cases • BIIF category seems promising for clinical...

  10. A Compositional Treatment of Polysemous Arguments in Categorial Grammar

    CERN Document Server

    Mineur, A M; Mineur, Anne-Marie; Buitelaar, Paul

    1995-01-01

    We discuss an extension of the standard logical rules (functional application and abstraction) in Categorial Grammar (CG), in order to deal with some specific cases of polysemy. We borrow from Generative Lexicon theory which proposes the mechanism of {\\em coercion}, next to a rich nominal lexical semantic structure called {\\em qualia structure}. In a previous paper we introduced coercion into the framework of {\\em sign-based} Categorial Grammar and investigated its impact on traditional Fregean compositionality. In this paper we will elaborate on this idea, mostly working towards the introduction of a new semantic dimension. Where in current versions of sign-based Categorial Grammar only two representations are derived: a prosodic one (form) and a logical one (modelling), here we introduce also a more detaled representation of the lexical semantics. This extra knowledge will serve to account for linguistic phenomena like {\\em metonymy\\/}.

  11. The representation of material categories in the brain.

    Science.gov (United States)

    Jacobs, Richard H A H; Baumgartner, Elisabeth; Gegenfurtner, Karl R

    2014-01-01

    Using textures mapped onto virtual nonsense objects, it has recently been shown that early visual cortex plays an important role in processing material properties. Here, we examined brain activation to photographs of materials, consisting of wood, stone, metal and fabric surfaces. These photographs were close-ups in the sense that the materials filled the image. In the first experiment, observers categorized the material in each image (i.e., wood, stone, metal, or fabric), while in an fMRI-scanner. We predicted the assigned material category using the obtained voxel patterns using a linear classifier. Region-of-interest and whole-brain analyses demonstrated material coding in the early visual regions, with lower accuracies for more anterior regions. There was little evidence for material coding in other brain regions. In the second experiment, we used an adaptation paradigm to reveal additional brain areas involved in the perception of material categories. Participants viewed images of wood, stone, metal, and fabric, presented in blocks with images of either different material categories (no adaptation) or images of different samples from the same material category (material adaptation). To measure baseline activation, blocks with the same material sample were presented (baseline adaptation). Material adaptation effects were found mainly in the parahippocampal gyrus, in agreement with fMRI-studies of texture perception. Our findings suggest that the parahippocampal gyrus, early visual cortex, and possibly the supramarginal gyrus are involved in the perception of material categories, but in different ways. The different outcomes from the two studies are likely due to inherent differences between the two paradigms. A third experiment suggested, based on anatomical overlap between activations, that spatial frequency information is important for within-category material discrimination.

  12. Brand importance across product categories in the Czech Republic

    Directory of Open Access Journals (Sweden)

    Formánek Tomáš

    2016-04-01

    Full Text Available This paper deals with customer loyalty to brands and provides an analysis of brand-related attitudes among Czech consumers. Brand loyalty is a very important aspect of competitive marketing and we contribute an empirically supported point of view on the topic. Based on primary data from a complex consumer survey carried out for the purpose of this study, we investigate the extent of brand loyalty across different product categories, mostly fast moving consumer goods (FMCG. For convenience, the analysis of our survey-data may be divided in two main areas. First, product categories are ranked according to their potential power to attract customers’ interest and loyalty towards brands. When loyalty programs are prepared, it is important to discern product categories where loyalty potential is weak from those categories that attract consumer loyalty. Second, sociodemographic features and lifestyle factors from the survey are evaluated with respect to different product categories, by means of logistic regression and subsequent average partial effect (APE analysis. A detailed and practically oriented interpretation of the empirical results is provided by the authors. However, both corporate marketers and academic readers can use the tables with empirical estimation outputs that are provided in this article to draw their own conclusions, which may be focused on the product category of interest and/or focused on any specific consumer group that is of particular interest. Among other topics, this paper emphasizes the fact that brand loyalty is a highly complex phenomenon and that it can and should be analysed from different perspectives.

  13. The representation of material categories in the brain

    Directory of Open Access Journals (Sweden)

    Richard Henrikus Augustinus Hubertus Jacobs

    2014-03-01

    Full Text Available Using textures mapped onto virtual nonsense objects, it has recently been shown that early visual cortex plays an important role in processing material properties. Here, we examined brain activation to photographs of materials, consisting of wood, stone, metal and fabric surfaces. These photographs were close-ups in the sense that the materials filled the image. In the first experiment, observers categorized the material in each image (i.e., wood, stone, metal, or fabric, while in an fMRI-scanner. We predicted the assigned material category using the obtained voxel patterns using a linear classifier. Region-of-interest and whole-brain analyses demonstrated material coding in the early visual regions, with lower accuracies for more anterior regions. There was little evidence for material coding in other brain regions. In the second experiment, we used an adaptation paradigm to reveal additional brain areas involved in the perception of material categories. Participants viewed images of wood, stone, metal, and fabric, presented in blocks with images of either different material categories (no adaptation or images of different samples from the same material category (material adaptation. To measure baseline activation, blocks with the same material sample were presented (baseline adaptation. Material adaptation effects were found mainly in the parahippocampal gyrus, in agreement with fMRI-studies of texture perception. Our findings suggest that the parahippocampal gyrus, early visual cortex, and possibly the supramarginal gyrus are involved in the perception of material categories, but in different ways. The different outcomes from the two studies are likely due to inherent differences between the two paradigms. A third experiment suggested, based on anatomical overlap between activations, that spatial frequency information is important for within-category material discrimination.

  14. Exploration of genetically encoded voltage indicators based on a chimeric voltage sensing domain

    Directory of Open Access Journals (Sweden)

    Yukiko eMishina

    2014-09-01

    Full Text Available Deciphering how the brain generates cognitive function from patterns of electrical signals is one of the ultimate challenges in neuroscience. To this end, it would be highly desirable to monitor the activities of very large numbers of neurons while an animal engages in complex behaviours. Optical imaging of electrical activity using genetically encoded voltage indicators (GEVIs has the potential to meet this challenge. Currently prevalent GEVIs are based on the voltage-sensitive fluorescent protein (VSFP prototypical design or on the voltage dependent state transitions of microbial opsins.We recently introduced a new VSFP design in which the voltage-sensing domain (VSD is sandwiched between a FRET pair of fluorescent proteins (termed VSFP-Butterflies and also demonstrated a series of chimeric VSD in which portions of the VSD of Ciona intestinalis voltage-sensitive phosphatase (Ci-VSP are substituted by homologous portions of a voltage-gated potassium channel subunit. These chimeric VSD had faster sensing kinetics than that of the native Ci-VSD. Here, we describe a new set of VSFPs that combine chimeric VSD with the Butterfly structure. We show that these chimeric VSFP-Butterflies can report membrane voltage oscillations of up to 200 Hz in cultured cells and report sensory evoked cortical population responses in living mice. This class of GEVIs may be suitable for imaging of brain rhythms in behaving mammalians.

  15. Capturing power at higher voltages from arrays of microbial fuel cells without voltage reversal

    KAUST Repository

    Kim, Younggy

    2011-01-01

    Voltages produced by microbial fuel cells (MFCs) cannot be sustainably increased by linking them in series due to voltage reversal, which substantially reduces stack voltages. It was shown here that MFC voltages can be increased with continuous power production using an electronic circuit containing two sets of multiple capacitors that were alternately charged and discharged (every one second). Capacitors were charged in parallel by the MFCs, but linked in series while discharging to the circuit load (resistor). The parallel charging of the capacitors avoided voltage reversal, while discharging the capacitors in series produced up to 2.5 V with four capacitors. There were negligible energy losses in the circuit compared to 20-40% losses typically obtained with MFCs using DC-DC converters to increase voltage. Coulombic efficiencies were 67% when power was generated via four capacitors, compared to only 38% when individual MFCs were operated with a fixed resistance of 250 Ω. The maximum power produced using the capacitors was not adversely affected by variable performance of the MFCs, showing that power generation can be maintained even if individual MFCs perform differently. Longer capacitor charging and discharging cycles of up to 4 min maintained the average power but increased peak power by up to 2.6 times. These results show that capacitors can be used to easily obtain higher voltages from MFCs, allowing for more useful capture of energy from arrays of MFCs. © 2011 The Royal Society of Chemistry.

  16. Universal arrows to forgetful functors from categories of topological algebra

    CERN Document Server

    Pestov, V G

    1992-01-01

    We survey the present trends in theory of universal arrows to forgetful functors from various categories of topological algebra and functional analysis to categories of topology and topological algebra. Among them are free topological groups, free locally convex spaces, free Banach-Lie algebras, and much more. An accent is put on relationship of those constructions with other areas of mathematics and their possible applications. A number of open problems is discussed; some of them belong to universal arrow theory, and others may hopefully become amenable to methods of this theory.

  17. The Hall module of an exact category with duality

    OpenAIRE

    Young, Matthew B.

    2012-01-01

    We construct from a finitary exact category with duality a module over its Hall algebra, called the Hall module, encoding the first order self-dual extension structure of the category. We study in detail Hall modules arising from the representation theory of a quiver with involution. In this case we show that the Hall module is naturally a module over the specialized reduced sigma-analogue of the quantum Kac-Moody algebra attached to the quiver. For finite type quivers, we explicitly determin...

  18. Categories vs. groupoids via generalised Mal'tsev properties

    OpenAIRE

    2014-01-01

    We study the difference between internal categories and internal groupoids in terms of generalised Mal'tsev properties---the weak Mal'tsev property on the one hand, and $n$-permutability on the other. In the first part of the article we give conditions on internal categorical structures which detect whether the surrounding category is naturally Mal'tsev, Mal'tsev or weakly Mal'tsev. We show that these do not depend on the existence of binary products. In the second part we focus on varieties ...

  19. Disentangling Memories. Complex (Be)longings and Social Categories

    DEFF Research Database (Denmark)

    Pedersen, Chistina Hee; Frølunde, Lisbeth

    2013-01-01

    of the participants and how meaning making connected to social categories express themselves in language. Two different methodological approaches were in play; Memory Work (Haug 1987, 1992, Haug et al 1994, Hee Pedersen 2008, Hyle et. al 2008, Wiederberg 2011) and Collective Biographies (Davies 2000a, 2000b, Davies...... belonging to a specific social or racial group. (Be)longing to a specific gendered and radicalised body constitutes in the analysis of these stories an excellent “location,” from which to analyse how socio/cultural and socio/economic categories like class, nationality and age intersect with one another...

  20. Structural similarity and category-specificity: a refined account

    DEFF Research Database (Denmark)

    Gerlach, Christian; Law, Ian

    2004-01-01

    It has been suggested that category-specific recognition disorders for natural objects may reflect that natural objects are more structurally (visually) similar than artefacts and therefore more difficult to recognize following brain damage. On this account one might expect a positive relationship...... range of candidate integral units will be activated and compete for selection, thus explaining the higher error rate associated with animals. We evaluate the model based on previous evidence from both normal subjects and patients with category-specific disorders and argue that this model can help...

  1. Dempster-Shafer information measures in category theory

    Science.gov (United States)

    Peri, Joseph S. J.

    2016-05-01

    In the Dempster Shafer context, one can construct new types of information measures based on belief and plausibility functions. These measures differ from those in Shannon's theory because, in his theory, information measures are based on probability functions. Other types of information measures were discovered by Kampe de Feriet and his colleagues in the French and Italian schools of mathematics. The objective of this paper is to construct a new category of information. I use category theory to construct a general setting in which the various types of information measures are special cases.

  2. On the loop space of a 2-category

    CERN Document Server

    del Hoyo, Matias L

    2010-01-01

    Every small category $C$ has a classifying space $BC$ associated in a natural way. This construction can be extended to other contexts and set up a fruitful interaction between categorical structures and homotopy types. In this paper we study the classifying space $B_2C$ of a 2-category $C$ and prove that, under certain conditions, the loop space $\\Omega_c B_2C$ can be recovered up to homotopy from the endomorphisms of a given object. We also present several subsidiary results that we develop to prove our main theorem.

  3. On the (un)suitability of semantic categories

    DEFF Research Database (Denmark)

    Rijkhoff, Jan

    2009-01-01

    Since Greenberg’s groundbreaking publication on universals of grammar, typologists have used semantic categories to investigate (constraints on) morphological and syntactic variation in the world’s languages and this tradition has been continued in the WALS project. It is argued here that the emp......Since Greenberg’s groundbreaking publication on universals of grammar, typologists have used semantic categories to investigate (constraints on) morphological and syntactic variation in the world’s languages and this tradition has been continued in the WALS project. It is argued here...

  4. Dual voltage power supply with 48 volt

    Energy Technology Data Exchange (ETDEWEB)

    Froeschl, Joachim; Proebstle, Hartmut; Sirch, Ottmar [BMW Group, Muenchen (Germany)

    2012-11-01

    Automotive electrics/electronics have just reached a period of tremendous change. High voltage systems for Hybrid, Plug-In Hybrid or Battery Electric Vehicles with high power electric motors, high energy accumulators and electric climate compressors will be introduced in order to achieve the challenging targets for CO{sub 2} emissions and energy efficiency and to anticipate the mobility of the future. Additionally, innovations and the continuous increase of functionality for comfort, safety, driver assistance and infotainment systems require more and more electrical power of the vehicle power supply at all. On the one hand side electrified vehicles will certainly achieve a significant market share, on the other hand side they will increase the pressure to conventional vehicles with combustion engines for fuel consumption and CO{sub 2} emissions. These vehicles will be enabled to keep their competitiveness by new functions and the optimization of their electric systems. A dual voltage power supply with 48 Volt and 12 Volt will be one of the key technologies to realize these requirements. The power capability of the existing 12 Volt power supply has reached its limits. Further potentials can only be admitted by the introduction of 48 Volt. For this reason the car manufacturers Audi, BMW, Daimler, Porsche and Volkswagen started very early on this item and developed a common specification of the new voltage range. Now, it is necessary to identify the probable systems at this voltage range and to start the developments. (orig.)

  5. High voltage pulse generator. [Patent application

    Science.gov (United States)

    Fasching, G.E.

    1975-06-12

    An improved high-voltage pulse generator is described which is especially useful in ultrasonic testing of rock core samples. An N number of capacitors are charged in parallel to V volts and at the proper instance are coupled in series to produce a high-voltage pulse of N times V volts. Rapid switching of the capacitors from the paralleled charging configuration to the series discharging configuration is accomplished by using silicon-controlled rectifiers which are chain self-triggered following the initial triggering of the first rectifier connected between the first and second capacitors. A timing and triggering circuit is provided to properly synchronize triggering pulses to the first SCR at a time when the charging voltage is not being applied to the parallel-connected charging capacitors. The output voltage can be readily increased by adding additional charging networks. The circuit allows the peak level of the output to be easily varied over a wide range by using a variable autotransformer in the charging circuit.

  6. The VELO High Voltage System Control Software

    CERN Document Server

    Rakotomiaramanana, B; Eklund, L; De Capua, S

    2010-01-01

    This note describes the VELO high voltage control software. The implementation of its structure as a PVSS Finite State Machine is emphasized. The main error conditions that may occur during operation is also discussed. The VELO HV software conforms to the specification of the VELO.

  7. Alternating current breakdown voltage of ice electret

    Science.gov (United States)

    Oshika, Y.; Tsuchiya, Y.; Okumura, T.; Muramoto, Y.

    2017-09-01

    Ice has low environmental impact. Our research objectives are to study the availability of ice as a dielectric insulating material at cryogenic temperatures. We focus on ferroelectric ice (iceXI) at cryogenic temperatures. The properties of iceXI, including its formation, are not clear. We attempted to obtain the polarized ice that was similar to iceXI under the applied voltage and cooling to 77 K. The polarized ice have a wide range of engineering applications as electronic materials at cryogenic temperatures. This polarized ice is called ice electret. The structural difference between ice electret and normal ice is only the positions of protons. The effects of the proton arrangement on the breakdown voltage of ice electret were shown because electrical properties are influenced by the structure of ice. We observed an alternating current (ac) breakdown voltage of ice electret and normal ice at 77 K. The mean and minimum ac breakdown voltage values of ice electret were higher than those of normal ice. We considered that the electrically weak part of the normal ice was improved by applied a direct electric field.

  8. Stray voltage zapping cows, pigs in Quebec

    Energy Technology Data Exchange (ETDEWEB)

    1988-05-18

    A power-supply malfunction is giving farm animals in Quebec a shock every time they eat or drink from metal troughs, making them nervous, lowering production, and stunting growth. In 2 years of negotiation with Hydro-Quebec, the utility has refused to correct the problem known as stray voltage. The shocks measure about 10 volts. It has been estimated the average Quebec dairy farmer with 40 cows is losing $15,000 to $20,000/y in reduced milk production. About 4,000 of the 23,000 Quebec pig and dairy farms are bothered by stray voltage. Hydro-Quebec has been asked to install filters that would reduce the problem; however, Hydro-Quebec attributes the stray voltage to the farmers' own equipment. A study conducted by the provincial Agriculture Department that measured stray voltage on 700 farms showed that 70% of the problem was Hydro-Quebec equipment. Farmers are prepared to solve the remaining 30% themselves.

  9. High voltage testing for the MAJORANA Demonstrator

    CERN Document Server

    Abgrall, N; Avignone, F T; Barabash, A S; Bertrand, F E; Bradley, A W; Brudanin, V; Busch, M; Buuck, M; Byram, D; Caldwell, A S; Chan, Y-D; Christofferson, C D; Chu, P -H; Cuesta, C; Detwiler, J A; Doe, P J; Dunagan, C; Efremenko, Yu; Ejiri, H; Elliott, S R; Fu, Z; Galindo-Uribarri, A; Giovanetti, G K; Goett, J; Green, M P; Gruszko, J; Guinn, I S; Guiseppe, V E; Henning, R; Hoppe, E W; Howard, S; Howe, M A; Jasinski, B R; Keeter, K J; Kidd, M F; Konovalov, S I; Kouzes, R T; LaFerriere, B D; Leon, J; Li, A; MacMullin, J; Martin, R D; Massarczyk, R; Meijer, S J; Mertens, S; Orrell, J L; O'Shaughnessy, C; Poon, A W P; Radford, D C; Rager, J; Rielage, K; Robertson, R G H; Romero-Romero, E; Shanks, B; Shirchenko, M; Snyder, N; Suriano, A M; Tedeschi, D; Thompson, A; Ton, K T; Trimble, J E; Varner, R L; Vasilyev, S; Vetter, K; Vorren, K; White, B R; Wilkerson, J F; Wiseman, C; Xu, W; Yakushev, E; Yu, C -H; Yumatov, V

    2016-01-01

    The MAJORANA Collaboration is constructing the MAJORANA Demonstrator, an ultra-low background, 44-kg modular high-purity Ge (HPGe) detector array to search for neutrinoless double-beta decay in Ge-76. The phenomenon of surface micro-discharge induced by high-voltage has been studied in the context of the MAJORANA Demonstrator. This eff?ect can damage the front-end electronics or mimic detector signals. To ensure the correct performance, every high-voltage cable and feedthrough must be capable of supplying HPGe detector operating voltages as high as 5 kV without exhibiting discharge. R&D measurements were carried out to understand the testing system and determine the optimum design configuration of the high-voltage path, including diff?erent improvements of the cable layout and feedthrough flange model selection. Every cable and feedthrough to be used at the MAJORANA Demonstrator was characterized and the micro-discharge eff?ects during the MAJORANA Demonstrator commissioning phase were studied. A stable c...

  10. Modeling of long High Voltage AC Underground

    DEFF Research Database (Denmark)

    Gudmundsdottir, Unnur Stella; Bak, Claus Leth; Wiechowski, W. T.

    2010-01-01

    This paper presents the work and findings of a PhD project focused on accurate high frequency modelling of long High Voltage AC Underground cables. The project is cooperation between Aalborg University and Energinet.dk. The objective of the project is to investigate the accuracy of most up to date...

  11. Ultra-low Voltage CMOS Cascode Amplifier

    DEFF Research Database (Denmark)

    Lehmann, Torsten; Cassia, Marco

    2000-01-01

    In this paper, we design a folded cascode operational transconductance amplifier in a standard CMOS process, which has a measured 69 dB DC gain, a 2 MHz bandwidth and compatible input- and output voltage levels at a 1 V power supply. This is done by a novel Current Driven Bulk (CDB) technique...

  12. Protection of Low Voltage CIGRE distribution Network

    DEFF Research Database (Denmark)

    Mustafa, Ghullam; Bak-Jensen, Birgitte; Bak, Claus Leth

    2013-01-01

    the inverters used for Photovoltaic (PV) and battery applications. The disconnection of the PV solar panels when in island mode is made by proposing switch dis-connecting devices. ABB is currently using these kinds of disconnection devices for the purpose of protecting solar panels against over voltages...

  13. An Inexpensive Source of High Voltage

    Science.gov (United States)

    Saraiva, Carlos

    2012-01-01

    As a physics teacher I like recycling old apparatus and using them for demonstrations in my classes. In physics laboratories in schools, sources of high voltage include induction coils or electronic systems that can be bought from companies that sell lab equipment. But these sources can be very expensive. In this article, I will explain how you…

  14. Voltage-controlled nanoscale reconfigurable magnonic crystal

    Science.gov (United States)

    Wang, Qi; Chumak, Andrii V.; Jin, Lichuan; Zhang, Huaiwu; Hillebrands, Burkard; Zhong, Zhiyong

    2017-04-01

    A nanoscale reconfigurable magnonic crystal is designed using voltage-controlled perpendicular magnetic anisotropy (PMA) in ferromagnetic-dielectric heterostructures. A periodic array of gate metallic strips is placed on top of a MgO/Co structure in order to apply a periodic electric field and to modify the PMA in Co. It is numerically demonstrated that the introduction of PMA, which can be realized experimentally via applying a voltage, modifies the spin-wave propagation and leads to the formation of band gaps in the spin-wave spectrum. The band gaps can be controlled, i.e., it is possible to switch band gaps on and off within a few tens of nanoseconds. The width and the center frequency of the band gaps are defined by the applied voltage. Finally, it is shown that the introduction of PMA to selected, rather than to all gate strips allows for a predefined modification of the band-gap spectra. The proposed voltage-controlled reconfigurable magnonic crystal opens a way to low power consumption magnonic applications.

  15. Offset Correction Techniques for Voltage Sense Amplifiers

    NARCIS (Netherlands)

    Groeneveld, S.

    2006-01-01

    This report deals with offset correction techniques for voltage sense amplifiers and is divided into two different parts: 1) mismatch and 2) offset correction techniques. First a literature study is done on the subject mismatch with specially focus on the future. Mismatch of a transistor is determin

  16. An Optoelectronic High-voltage Probe for Measuring Impulse Voltage Distribution of HVDC Converter Valve

    Institute of Scientific and Technical Information of China (English)

    方志; 邱毓昌

    2007-01-01

    A high-voltage optoelectronic probe is developed for measuring impulse voltage distribution along thyristor units in the HVDC converter valve. The dimension of the resistive voltage divider is optimized by means of numerical compttation of electric field. A pulse frequency modulation (PFM) mode is adopted for the data transmission link because of its immunity to high-intensity electromagnetic interference. Experimental results indicate that the linearity deviation for the whole measuring system is within ± 0.15 %, and therefore it can meet requirements specified by IEC60700-1.

  17. Voltage-induced reduction of graphene oxide

    Science.gov (United States)

    Faucett, Austin C.

    Graphene Oxide (GO) is being widely researched as a precursor for the mass production of graphene, and as a versatile material in its own right for flexible electronics, chemical sensors, and energy harvesting applications. Reduction of GO, an electrically insulating material, into reduced graphene oxide (rGO) restores electrical conductivity via removal of oxygen-containing functional groups. Here, a reduction method using an applied electrical bias, known as voltage-induced reduction, is explored. Voltage-induced reduction can be performed under ambient conditions and avoids the use of hazardous chemicals or high temperatures common with standard methods, but little is known about the reduction mechanisms and the quality of rGO produced with this method. This work performs extensive structural and electrical characterization of voltage-reduced GO (V-rGO) and shows that it is competitive with standard methods. Beyond its potential use as a facile and eco-friendly processing approach, V-rGO reduction also offers record high-resolution patterning capabilities. In this work, the spatial resolution limits of voltage-induced reduction, performed using a conductive atomic force microscope probe, are explored. It is shown that arbitrary V-rGO conductive features can be patterned into insulating GO with nanoscale resolution. The localization of voltage-induced reduction to length scales < 10 nm allows studies of reduction reaction kinetics, using electrical current obtained in-situ, with statistical robustness. Methods for patterning V-rGO nanoribbons are then developed. After presenting sub-10nm patterning of V-rGO nanoribbons in GO single sheets and films, the performance of V-rGO nanoribbon field effect transistors (FETs) are demonstrated. Preliminary measurements show an increase in electrical current on/off ratios as compared to large-area rGO FETs, indicating transport gap modulation that is possibly due to quantum confinement effects.

  18. Mitigation Voltage Sag in Power System by Static Synchronous Compensator

    Directory of Open Access Journals (Sweden)

    Prechanon Kumkratug

    2010-01-01

    Full Text Available Problem statement: The disturbance in power system is unavoidable situation. It cause in voltage sag in power system. Approach: This study applied the STATCOM to mitigate voltage of the system. The mathematical model of power system equipped with a STATCOM is systematically derived. The presented mathematical model is shown how it effects on voltage sag improvement. The simulation results are tested on a Single Machine Infinite bus. The proposed method is equipped in sample system with severe disturbance. The variation voltage of the system without and with a STATCOM is plotted and compared. Results: It was found that the system without a STATCOM has high voltage variation especially voltage sags whereas with a STATCOM the system voltage has small voltage sages. Conclusion: From the simulation results, the STATCOM can mitigate voltage of power system.

  19. A battery-based, low-noise voltage source

    Science.gov (United States)

    Wagner, Anke; Sturm, Sven; Schabinger, Birgit; Blaum, Klaus; Quint, Wolfgang

    2010-06-01

    A highly stable, low-noise voltage source was designed to improve the stability of the electrode bias voltages of a Penning trap. To avoid excess noise and ground loops, the voltage source is completely independent of the public electric network and uses a 12 V car battery to generate output voltages of ±15 and ±5 V. First, the dc supply voltage is converted into ac-voltage and gets amplified. Afterwards, the signal is rectified, filtered, and regulated to the desired output value. Each channel can deliver up to 1.5 A. The current as well as the battery voltage and the output voltages can be read out via a universal serial bus (USB) connection for monitoring purposes. With the presented design, a relative voltage stability of 7×10-7 over 6.5 h and a noise level equal or smaller than 30 nV/√Hz is achieved.

  20. Identification of problems when using long high voltage AC cable in transmission system II: Resonance & Harmonic resonance

    DEFF Research Database (Denmark)

    Rahimi, Saeed; Wiechowski, W.; Randrup, M.;

    2008-01-01

    cable in transmission system. The objective of this paper and the companion paper is to address the most important problems expected in transmission system with relatively larger share of long HV underground cables. The end goal will be a guideline to special solutions and precautions to avoid dangerous...... over voltage problems and also resonance problems in a transmission network with future increased share of cables. Two major categories of problems are switching transient and resonance problems. In each category of the possible problems, first some theoretical background is provided...... and then the problem and countermeasures are discussed. In this paper most important resonance problems are addressed and discussed. Three main categories of resonance problems are: Near Resonance, Harmonic resonance and Ferroresonance....