pinecone/core-2020-05-10-deduplication huggingface dataset:
The Kernel Matrix Diffie-Hellman assumption

The final publication is available at https://link.springer.com/chapter/10.1007%2F978-3-662-53887-6_27We put forward a new family of computational assumptions, the Kernel Matrix Diffie-Hellman Assumption. Given some matrix A sampled from some distribution D, the kernel assumption says that it is hard to find “in the exponent” a nonzero vector in the kernel of A¿ . This family is a natural computational analogue of the Matrix Decisional Diffie-Hellman Assumption (MDDH), proposed by Escala et al. As such it allows to extend the advantages of their algebraic framework to computational assumptions. The k-Decisional Linear Assumption is an example of a family of decisional assumptions of strictly increasing hardness when k grows. We show that for any such family of MDDH assumptions, the corresponding Kernel assumptions are also strictly increasingly weaker. This requires ruling out the existence of some black-box reductions between flexible problems (i.e., computational problems with a non unique solution).Peer ReviewedPostprint (author's final draft
Structural impact on the nanoscale optical properties of InGaN core-shell nanorods

III-nitride core-shell nanorods are promising for the development of high efficiency light emitting diodes and novel optical devices. We reveal the nanoscale optical and structural properties of core-shell InGaN nanorods formed by combined top-down etching and regrowth to achieve non-polar sidewalls with a low density of extended defects. While the luminescence is uniform along the non-polar {1-100} sidewalls, nano-cathodoluminescence shows a sharp reduction in the luminescent intensity at the intersection of the non-polar {1-100} facets. The reduction in the luminescent intensity is accompanied by a reduction in the emission energy localised at the apex of the corners. Correlative compositional analysis reveals an increasing indium content towards the corner except at the apex itself. We propose that the observed variations in the structure and chemistry are responsible for the changes in the optical properties at the corners of the nanorods. The insights revealed by nano-cathodoluminescence will aid in the future development of higher efficiency core-shell nanorods
Determinants and value relevance of UK CEO pay slice

This paper studies the CEO pay slice (CPS) of UK listed firms during the period 2003 to 2009. We investigate the determinants of CPS. We study the links between CPS and measures of firm performance. We find that firms with higher levels of corporate governance ratings and those with more independent boards tend to have higher CPS. In addition, we find that CEOs are more likely to receive lower compensation when they chair the board and when they work in firms with large board size. We also find that higher CPS is positively associated with firm performance after controlling for the firm-specific characteristics and corporate governance variables. We get compatible results when we examine the association between equity-based CPS and firm performance. Our results remain robust to alternative accounting measures of firm performance. Our results suggest that high UK CPS levels do indeed reflect top managerial talent rather than managerial power
A systematic review of platinum and taxane resistance from bench to clinic: an inverse relationship

We undertook a systematic review of the pre-clinical and clinical literature for studies investigating the relationship between platinum and taxane resistance. Medline was searched for 1) cell models of acquired drug resistance reporting platinum and taxane sensitivities and 2) clinical trials of platinum or taxane salvage therapy in ovarian cancer. 137 models of acquired drug resistance were identified. 68.1% of cisplatin-resistant cells were sensitive to paclitaxel and 66.7% of paclitaxel-resistant cells were sensitive to cisplatin. A similar inverse pattern was observed for cisplatin vs docetaxel, carboplatin vs paclitaxel and carboplatin vs docetaxel. These associations were independent of cancer type, agents used to develop resistance and reported mechanisms of resistance. 65 eligible clinical trials of paclitaxel-based salvage after platinum therapy were identified. Studies of single agent paclitaxel in platinum-resistant ovarian cancer where patients had previously recieved paclitaxel had a pooled response rate of 35.3% n=232, compared to 22% in paclitaxel naïve patients n=1918 (p<0.01 Chi-squared). Suggesting that pre-treatment with paclitaxel may improve the response of salvage paclitaxel therapy. The response rate to paclitaxel/platinum combination regimens in platinum-sensitive ovarian cancer was 79.5% n=88 compared to 49.4% n=85 for paclitaxel combined with other agents (p<0.001 Chi-squared), suggesting a positive interaction between taxanes and platinum. Therefore the inverse relationship between platinum and taxanes resistance seen in cell models is mirrored in the clinical response to these agents in ovarian cancer. An understanding of the cellular and molecular mechanisms responsible would be valuable in predicting response to salvage chemotherapy and may identify new therapeutic targets
Thermal stability of laser treated die material for semi-solid metal forming

This paper presents laser surface modification work performed to improve the lifetime of die materials. Die material AISI H13, with typical hardness in the range of 42 to 48 HRC, offers high wear and corrosion resistance. However the cyclic high temperature conditions along with exposure to high viscosity molten metal in semi-solid forming cause the die to wear and crack with resultant shortened die lifetime. In this study, the thermal stability of die material at elevated temperature was investigated through micro-hardness testing and a metallographic study. AISI H13 samples were laser glazed using CO2 continuous wave mode laser with 10.6 μm wavelength. Samples were attached to a specially designed rotating chuck to enable it to be rotated at speeds up to 1500 rpm and allow flat surface glazing to take place. The micro-hardness was measured for as-glazed samples and annealed samples which were held at temperatures ranging from 550oC to 800oC with 50oC intervals. The metallographic study conducted examined the formation of three zones at different depths which were the glazed zone, the heat affected zone and the substrate. As a result of rapid heating and cooling from the laser glazing process, a metallic glass layer was developed which exhibited an average micro-hardness of 900 HV when exposed to 3.34E+10 W/m2 laser irradiance within a range of 0.0011 to 0.0018 s exposure time. Crystallization in glazed zone increased as the annealing temperature increased. As the annealing temperature reached above approximately 600oC, the micro-hardness decreased to approximately 600 HV (equivalent to approx. 54 HRC) due to local crystallization. These findings show potential direct application of glazed dies for non-ferrous semi-solid forming and the requirement for thermal barrier protection for application at higher temperatures
Object-based semi-automatic approach for forest structure characterization using lidar data in heterogeneous Pinus sylvestris stands.

In this paper, we present a two-stage approach for characterizing the structure of Pinus sylvestris L. stands in forests of central Spain. The first stage was to delimit forest stands using eCognition and a digital canopy height model (DCHM) derived from lidar data. The polygons were then clustered (k-means algorithm) into forest structure types based on the DCHMdata within forest stands. Hypsographs of each polygon and field data validated the separability of structure types. In the study area, 112 polygons of Pinus sylvestris were segmented and classified into five forest structure types, ranging from high dense forest canopy (850 trees ha_1 and Lorey´ s height of 17.4 m) to scarce tree coverage (60 tree ha_1 and Lorey´ s height of 9.7 m). Our results indicate that the best variables for the definition and characterization of forest structure in these forests are the median and standard deviation (S.D.), both derived from lidar data. In these forest types, lidar median height and standard deviation (S.D.) varied from 15.8 m (S.D. of 5.6 m) to 2.6 m (S.D. of 4.5 m). The present approach could have an operational application in the inventory procedure and forest management plans
On-chip III-V monolithic integration of heralded single photon sources
  and beamsplitters

We demonstrate a monolithic III-V photonic circuit combining a heralded
single photon source with a beamsplitter, at room temperature and telecom
wavelength. Pulsed parametric down-conversion in an AlGaAs waveguide generates
counterpropagating photons, one of which is used to herald the injection of its
twin into the beamsplitter. We use this configuration to implement an
integrated Hanbury-Brown and Twiss experiment, yielding a heralded second-order
correlation $g^{(2)}_{\rm her}(0)=0.10 \pm 0.02$ that confirms single-photon
operation. The demonstrated generation and manipulation of quantum states on a
single III-V semiconductor chip opens promising avenues towards real-world
applications in quantum information
Annealing tests of in-pile irradiated oxide coated U–Mo/Al–Si dispersed nuclear fuel

Authors do acknowledge the MERARG team for their experimental work (CEA) and F. Charollais, J. Noirot and finally B. Kapusta for their advices and comments. This study was supported by a combined Grant (FRM0911) of the Bundesministerium für Bildung und Forschung (BMBF) and the Bayerisches Staatsministerium für Wissenschaft, Forschung und Kunst (StMWFK).U–Mo/Al based nuclear fuels have been worldwide considered as a promising high density fuel for the conversion of high flux research reactors from highly enriched uranium to lower enrichment. In this paper, we present the annealing test up to 1800°C of in-pile irradiated U–Mo/Al–Si fuel plate samples.
More than 70% of the fission gases (FGs) are released during two major FG release peaks around 500°C and 670°C. Additional characterisations of the samples by XRD, EPMA and SEM suggest that up to 500°C FGs are released from IDL/matrix interfaces. The second peak at 670°C representing the main release of FGs originates from the interaction between U–Mo and matrix in the vicinity of the cladding
The influence of laser assistance on the machinability of the titanium alloy Ti555-3

The Ti533-3 alloy is a new titanium alloy which is starting to see increased use in the aeronautical domain to improve the durability of components and to optimize the weight/resistance ratio. This alloy is characterized by greater resistance compared to the more commonly used titanium alloys such as Ti6Al4V. However, a disadvantage of the Ti533-3 alloy is that it is very difficult to machine. In this work, the use of laser-assisted machining has been tested to improve chip formation by a thermal softening phenomenon and to improve the machining productivity of the alloy. A parametric investigation of laser assistance on the machinability of the Ti555-3 titanium alloy shows that: (1) the cutting forces can be greatly decreased if the surface temperature is high; (2) the thermal gradient induced by laser heating modifies the surface integrity in terms of strain hardening and residual stresses in the workpiece; and (3) the chip formation mechanisms are also changed, by increasing the sawteeth frequency when using laser assistanc
An improved assumed strain solid-shell element formulation with physical stabilization for geometric non-linear applications and elastic-plastic stability analysis

In this paper, the earlier formulation of the SHB8PS finite element is revised in order to eliminate some persistent membrane and shear locking phenomena. This new formulation consists of a solid-shell element based on a purely three-dimensional approach. More specifically, the element has eight nodes, with displacements as the only degrees of freedom, as well as an arbitrary number of integration points, with a minimum number of two, distributed along the 'thickness' direction. The resulting derivation, which is computationally efficient, can then be used for the modeling of thin structures, while providing an accurate description of the various through-thickness phenomena. A reduced integration scheme is used to prevent some locking phenomena and to achieve an attractive, low-cost formulation. The spurious zero-energy modes due to this in-plane one-point quadrature are efficiently controlled using a physical stabilization procedure, whereas the strain components corresponding to locking modes are eliminated with a projection technique following the assumed strain method. In addition to the extended and detailed formulation presented in this paper, particular attention has been focused on providing full justification regarding the identification of hourglass modes in relation to rank deficiencies. Moreover, an attempt has been made to provide a sound foundation to the derivation of the co-rotational coordinate frame, on which the calculations of the stabilization stiffness matrix and internal load vector are based. Finally to assess the effectiveness and performance of this new formulation, a set of popular benchmark problems is investigated, involving geometric non-linear analyses as well as elastic-plastic stability issues
Examining and improving the effectiveness of relevance feedback for retrieval of scanned text documents

Important legacy paper documents are digitized and collected in online accessible archives. This enables the preservation, sharing, and significantly the searching of\ud
these documents. The text contents of these document images can be transcribed automatically using OCR systems and then stored in an information retrieval system. However, OCR systems make errors in character recognition which have previously been shown to impact on document retrieval behaviour. In particular relevance feedback query-expansion methods, which are often effective for improving electronic\ud
text retrieval, are observed to be less reliable for retrieval of scanned document images. Our experimental examination of the effects of character recognition errors\ud
on an ad hoc OCR retrieval task demonstrates that, while baseline information retrieval can remain relatively unaffected by transcription errors, relevance feedback via query expansion becomes highly unstable. This paper examines the reason for this behaviour, and introduces novel modifications to standard relevance feedback methods. These methods are shown experimentally to improve the effectiveness of relevance feedback for errorful OCR transcriptions. The new methods combine similar recognised character strings based on term collection frequency and a string edit-distance measure. The techniques are domain independent and make no use of external resources such as dictionaries or training data
Acoustic analysis of voice using WPCVox: a comparative study with Multi Dimensional Voice Program

In this study, two diVerent tools developed for the parametric extraction and acoustic analysis of voice samples are compared. The main goal of the paper is to contrast the results obtained using the classical Multi Dimensional Voice Program (MDVP), with the results obtained with the novel WPCVox. The aim of this comparison was to Wnd diVerences and similarities in the parameters extracted with both systems in order to make comparison of measurements and data transfer among both equipments. The study was carried out in two stages: in the Wrst, a wide sample of healthy voices belonging to Spanishspeaking adults from both genders were used to carry out a direct comparison between the results given by MDVP and those obtained with WPCVox. In the second stage, a sample of 200 speakers (53 normal and 173 pathological) taken from a commercially available database of voice disorders were used to demonstrate the usefulness of WPCVox for the acoustic analysis and the characterization of normal and pathological voices. The results conclude that WPCVox provides very reliable measurements which are very similar to those obtained using MDVP, and very similar capabilities to discriminate among normal and pathological voices
Unstable manifold, Conley index and fixed points of flows

We study dynamical and topological properties of the unstable manifold of isolated invariant compacta of flows. We show that some parts of the unstable manifold admit sections carrying a considerable amount of information. These sections enable the construction of parallelizable structures which facilitate the study of the flow. From this fact, many nice consequences are derived, specially in the case of plane continua. For instance, we give an easy method of calculation of the Conley index provided we have some knowledge of the unstable manifold and, as a consequence, a relation between the Brouwer degree and the unstable manifold is established for smooth vector fields. We study the dynamics of non-saddle sets, properties of existence or non-existence of fixed points of flows and conditions under which attractors are fixed points, Morse decompositions, preservation of topological properties by continuation and classify the bifurcations taking place at a critical point
Status of ANTARES in Nov 2005

This article reports on the status of the ANTARES Neutrino Telescope project as of November 2005. The highlights of the activities during 2005 are the deployment and operation of an instrumentation line which has been taking data since April 2005 and the deployment of a complete mechanical test line in the spring of 2005. The first data from the operation of the instrumentation line is presented. The status report gives the plans for the construction of the full ANTARES detector which is planned for completion in 2007
Grid as a bioinformatic tool

The grid is a promising tool to resolve the crucial issue of software and data integration in biology. In this paper, we have reported on our experience in the deployment of bioinformatic grid applications within the framework of the DataGrid project. These applications inquired the potential impact of grids for CPU demanding algorithms and bioinformatics web portals and for the update and distribution of biological databases. Grid computing tests showed how resources sharing improves the current practice of bioinformatics. Reached performance demonstrated the interest of the grid too
Geometrical analysis of thread milling – Part 2:Calculation of uncut chip thickness

Thread milling offers interesting possibilities for machining internal or external threads. This
machining technique uses a mill with a triangular profile for metric threads and a helical interpolation
strategy. Thus, the uncut chip thickness can not be easily evaluated from a simplified approach. The present study deals with a model for calculating uncut chip thickness during internal thread milling. This step is needed to understand and model the cutting forces. The model developed uses the geometrical definitions of the mill, and takes into account the milling mode and the cutting conditions. The link with the interferences between the tool and the thread is also established and corroborates a previous study. A full analyticalformulation of the problem is proposed, and results from different milling settings are presented
Secular changes in body height and weight of Portuguese boys over one century

This study examines secular changes in attained height and weight in student boys from a military boarding school (Colégio Militar) in Lisbon, Portugal. Data for 1899-1906, 1929-1936, 1961-1966, and 1999-2006 obtained from the archives and medical files of the Colégio Militar were used in this study. In a century Portuguese boys increased in height by 10.5 cm at age 10 to 19.1 cm at age 14, at a mean increase of 1.54 cm per decade. The gain in weight was between 8.7 and 18.9 kg for 10- and 14-year-old boys, respectively, at a mean increase of 1.54 kg per decade. In the same period, age at peak height and weight velocity advanced sim2 years, showing an acceleration of developmental tempo. However, most of the real gain in height and weight and the decrease in pubertal age occurred after 1961-1966. This mirrors major improvements in social and economic conditions that initiated in Portugal in the 1960s, and then by political events in the 1970s that promoted further progress. Am. J. Hum. Biol., 2008. © 2008 Wiley-Liss, Inc.http://dx.doi.org/10.1002/ajhb.2071
Non-osseous calcaneonavicular coalition in the Portuguese prehistoric population: report of two cases

This paper reports articular surface defects detected in three foot bones. These were exhumed from Portuguese collective burial places, Hipogeu de São Paulo II (artificial cave, Almada) and Necrópole da Serra da Roupa (shelter, Columbeira) dated to the Late Neolithic and Chalcolithic periods. Other aetiologies were presented, but non-osseous calcaneonavicular coalition proved to be the most probable explanation for the unusual morphology detected in two calcanei and one navicular bone. Copyright © 2005 John Wiley & Sons, Ltd.http://dx.doi.org/10.1002/oa.80
Extension of the characteristic equation to absorption chillers with adiabatic absorbers

Various researchers have developed models of conventional H2O–LiBr absorption machines with the aim of predicting their performance. In this paper, the methodology of characteristic equations developed by Hellmann et al. (1998) is applied. This model is able to represent the capacity of single effect absorption chillers and heat pumps by means of simple algebraic equations. An extended characteristic equation based on a characteristic temperature difference has been obtained, considering the facility features. As a result, it is concluded that for adiabatic absorbers a subcooling temperature must be specified. The effect of evaporator overflow has been characterized. Its influence on cooling capacity has been included in the extended characteristic equation. Taking into account the particular design and operation features, a good agreement between experimental performance data and those obtained through the extended characteristic equation has been achieved at off-design operation. This allows its use for simulation and control purposes
Interband absorption of photons by extended states in intermediate band solar cells

This paper considers sub-bandgap photon absorption in an InAs/GaAs quantum dot matrix. Absorption coefficients are calculated for transitions from the extended states in the valence band to confined states in the conduction band. This completes a previous body of work in which transitions between bound states were calculated. The calculations are based on the empirical k·p Hamiltonian considering the quantum dots as parallelepipeds. The extended states may be only partially extended?in one or two dimensions?or extended in all three dimensions. It is found that extended-to-bound transitions are, in general, weaker than bound-to-bound transitions, and that the former are weaker when the initial state is extended in more coordinates. This study is of direct application to the research of intermediate band solar cells and other semiconductor devices based on light absorption in semiconductors nanostructured with quantum dots
Massive Spin-2 Field in De Sitter Space

In this paper we present a covariant quantization of the ``massive'' spin-2 field on de Sitter (dS) space. By ``massive'' we mean a field which carries a specific principal series representation of the dS group. The work is in the direct continuation of previous ones concerning the scalar, the spinor and the vector cases. The quantization procedure, independent of the choice of the coordinate system, is based on the Wightman-Garding axiomatic and on analyticity requirements for the two-point function in the complexified pseudo-Riemanian manifold. Such a construction is necessary in view of preparing and comparing with the dS conformal spin-2 massless case (dS linear quantum gravity) which will be considered in a forthcoming paper and for which specific quantization methods are needed