Search results for "Complete"
showing 10 items of 490 documents
On the Intrinsic Complexity of Learning
1995
AbstractA new view of learning is presented. The basis of this view is a natural notion of reduction. We prove completeness and relative difficulty results. An infinite hierarchy of intrinsically more and more difficult to learn concepts is presented. Our results indicate that the complexity notion captured by our new notion of reduction differs dramatically from the traditional studies of the complexity of the algorithms performing learning tasks.
Conifold Transitions and Mirror Symmetry for Calabi-Yau Complete Intersections in Grassmannians
1997
In this paper we show that conifold transitions between Calabi-Yau 3-folds can be used for the construction of mirror manifolds and for the computation of the instanton numbers of rational curves on complete intersection Calabi-Yau 3-folds in Grassmannians. Using a natural degeneration of Grassmannians $G(k,n)$ to some Gorenstein toric Fano varieties $P(k,n)$ with conifolds singularities which was recently described by Sturmfels, we suggest an explicit mirror construction for Calabi-Yau complete intersections $X \subset G(k,n)$ of arbitrary dimension. Our mirror construction is consistent with the formula for the Lax operator conjectured by Eguchi, Hori and Xiong for gravitational quantum c…
Nonlinear σ -models in the Eddington-inspired Born-Infeld gravity
2020
In this paper we consider two different nonlinear $\sigma$-models minimally coupled to Eddington-inspired Born-Infeld gravity. We show that the resultant geometries represent minimal modifications with respect to those found in GR, though with important physical consequences. In particular, wormhole structures always arise, though this does not guarantee by itself the geodesic completeness of those space-times. In one of the models, quadratic in the canonical kinetic term, we identify a subset of solutions which are regular everywhere and are geodesically complete. We discuss characteristic features of these solutions and their dependence on the relationship between mass and global charge.
External derivations of internal groupoids
2008
If His a G-crossed module, the set of derivations of Gin H is a monoid under the Whitehead product of derivations. We interpret the Whitehead product using the correspondence between crossed modules and internal groupoids in the category of groups. Working in the general context of internal groupoids in a finitely complete category, we relate derivations to holomorphisms, translations, affine transformations, and to the embedding category of a groupoid. (C) 2007 Elsevier B.V. All rights reserved.
Das Problem der âentscheidenden Experimenteâ
1986
In this historical essay an attempt is made to discuss the problem of decisive experiments both from the point of view of History of Science and of Philosophy of Science. The first part deals with Francis Bacon's idea of instantiae crucis and with the use of the term experimentum crucis mainly in optics. With respect to the experimental confirmation of Maxwell's electrodynamics the Duhem-Quine Thesis is discussed. Duhem had argued that not a single hypothesis but only a complete theory is examined by experiment. So a single experiment neither can prove nor can disprove a single hypothesis. With regard to Bucherer's and Neumann's data concerning the velocity-dependence of the electron's mass…
How Long-Term Contracts can Mitigate Inefficient Renegotiation Arising Due to Loss Aversion
2021
A loss-averse buyer and seller face an uncertain environment. Should they write a long-term contract or wait until the state of the world is realized? I show that simple long-term contracts perform better than insinuated in Herweg and Schmidt (2015), even though loss aversion makes renegotiation sometimes inefficient. During renegotiation, the outcome induced by the long-term contract constitutes the reference point to which the parties compare gains and losses induced by the renegotiated transaction. Whereas Herweg and Schmidt consider that the long-term contract is always performed, it should not in "bad" states. This alters the threat point in renegotiation, making it easier to renegotia…
Prediction of the carbon-13 NMR chemical shifts of polysubstituted benzenes with homogeneous substituents
1991
A new incremental scheme for the calculation of the 13C NMR chemical shifts in polysubstituted benzenes with homogeneous substituents was derived and applied to spectral prediction for C6XnH6−n where XCH3, C2H5, i-C3H7, CF3, F, Cl, Br, COOH. Owing to the use of only two-particle increments the procedure is simple enough to be carried out on hand calculators, and gives complete agreement with experimental values within a few tenths of a ppm in all cases compared (76 compounds). The 13C NMR chemical shift was predicted for hexaethylbenzene with a good fit to the experiment value, and also for 20 unmeasured compounds. The present scheme can be used as an algorithm in structure-searching progra…
A Multistep Methodology for the Evaluation of Human Resources Using the Evidence Theory
2013
The paper aims at proposing a model for the human resources evaluation as regards to a set of skills. Specifically, it starts sfrom the judgments expressed by a team of experts on the basis of their previous working experiences with the resource to be evaluated. Information arising from experts is successively handled by the analyst and aggregated to determine the resource suitability or unsuitability. The Dempster–Shafer theory is proposed here as an appropriate tool to deal with both the uncertainty of experts due to the incomplete knowledge about resources to be evaluated and that of the analyst to convert expert judgments in terms of resource suitability/unsuitability. Furthermore, the …
Experimental Modeling of Submerged Pivot Weir
2020
An inclined rectangular overflow structure, also called a pivot weir, consists of a rectangular plate, angled downstream from the vertical, that can be used as an upstream water level control device. A pivot weir is submerged when the upstream water level is influenced by the downstream flow depth. In this paper, to investigate factors influencing submerged flow conditions, an extensive experimental program including 251 experimental trials was carried out using weir inclination angles of 39.6°, 53°, 85°, and 90° and weir heights ranging from 0.263 to 0.312 m. A formula to distinguish between free and submerged flow conditions was developed using the Π theorem of dimensional analysis and th…
Cultural adaptation of the Smiling is Fun program for the treatment of depression in the Ecuadorian public health care system: A study protocol for a…
2021
Background Depression is one of the world's major health problems. Due to its high prevalence, it constitutes the first cause of disability among the Americas, where only a very low percentage of the population receives the adequate evidence-based psychological treatment. Internet-Based Interventions (IBIs) are a great alternative to reduce the treatment gap for mental disorders. Although there are several studies in low-and middle-income countries proving IBIs' feasibility and acceptability, there is still little evidence of the effectiveness in diverse social and cultural contexts such as Latin America. Methods Two studies will be described: Study 1 is focused on the cultural adaptation o…