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2014 - AAAI

Knowledge Graph Embedding by Translating on Hyperplanes

We deal with embedding a large scale knowledge graph composed of entities and relations into a continuous vector space. TransE is a promising method proposed recently, which is very efficient while achieving state-of-the-art predictive performance. We discuss some mapping properties of relations which should be considered in embedding, such as reflexive, one-to-many, many-to-one, and many-to-many. We note that TransE does not do well in dealing with these properties. Some complex models are capable of preserving these mapping properties but sacrifice efficiency in the process. To make a good trade-off between model capacity and efficiency, in this paper we propose TransH which models a relation as a hyperplane together with a translation operation on it. In this way, we can well preserve the above mapping properties of relations with almost the same model complexity of TransE. Additionally, as a practical knowledge graph is often far from completed, how to construct negative examples to reduce false negative labels in training is very important. Utilizing the one-to-many/many-to-one mapping property of a relation, we propose a simple trick to reduce the possibility of false negative labeling. We conduct extensive experiments on link prediction, triplet classification and fact extraction on benchmark datasets like WordNet and Freebase. Experiments show TransH delivers significant improvements over TransE on predictive accuracy with comparable capability to scale up.

2006 - Journal of Accounting Research

Founding Family Ownership and Earnings Quality

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This study investigates the relation between founding family ownership and earnings quality using data from the Standard & Poor's 500 companies. Existing literature has documented that financial reporting is of higher quality when firms have stronger corporate governance mechanisms and when there is greater demand for quality financial reporting. I provide two competing theories of the effect of founding family ownership on the demand and supply of earnings quality: the entrenchment effect and the alignment effect. The empirical results show that, on average, founding family ownership is associated with higher earnings quality. In particular, I find consistent evidence that founding family ownership is associated with lower abnormal accruals, greater earnings informativeness, and less persistence of transitory loss components in earnings. In addition, the results suggest a nonlinear relation between family ownership and earnings quality.

1981 - Physical Review Letters

Effective Harmonic-Fluid Approach to Low-Energy Properties of One-Dimensional Quantum Fluids

A universal description of the low-energy properties of one-dimensional quantum fluids, based on a harmonic theory of long-wavelength density fluctuations with use of renormalized parameters, is outlined. The structure of long-distance correlations of a spinless fluid is obtained, showing the essential similarity of one-dimensional Bose and Fermi fluids. The results are illustrated by application to the one-dimensional Bose fluid with $\ensuremath{\delta}$-function interaction.

2004 - Swarm Robotics

Swarm Robotics: From Sources of Inspiration to Domains of Application

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Swarm robotics is a novel approach to the coordination of large numbers of relatively simple robots which takes its inspiration from social insects. This paper proposes a definition to this newly emerging approach by 1) describing the desirable properties of swarm robotic systems, as observed in the system-level functioning of social insects, 2) proposing a definition for the term swarm robotics, and putting forward a set of criteria that can be used to distinguish swarm robotics research from other multi-robot studies, 3) providing a review of some studies which can act as sources of inspiration, and a list of promising domains for the utilization of swarm robotic systems.

1998 - Smart Materials and Structures

An experimental study of MR dampers for seismic protection

In this paper, the efficacy of magnetorheological (MR) dampers for seismic response reduction is examined. To investigate the performance of the MR damper, a series of experiments was conducted in which the MR damper is used in conjunction with a recently developed clipped-optimal control strategy to control a three-story test structure subjected to a one-dimensional ground excitation. The ability of the MR damper to reduce both peak responses, in a series of earthquake tests, and rms responses, in a series of broadband excitation tests, is shown. Additionally, because semi-active control systems are nonlinear, a variety of disturbance amplitudes are considered to investigate the performance of this control system over a variety of loading conditions. For each case, the results for three clipped-optimal control designs are presented and compared to the performance of two passive systems. The results indicate that the MR damper is quite effective for structural response reduction over a wide class of seismic excitations.

1972 - Quarterly Journal of the Royal Meteorological Society

Momentum, mass and heat exchange of vegetation

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Vegetation is treated as a complex surface roughness to which the transfer of mass or heat encounters greater aerodynamic resistance, γP, than the transfer of momentum, γD. The excess resistance (γP – γD) is equated to B/u*, where B−1 is the non-dimensional bulk parameter introduced by Owen and Thomson (1963) and used by Chamberlain (1966, 1968). A general expression is obtained for B−1 in terms of the exchange characteristics of the individual elements of a vegetative canopy: this expression does not contain the surface roughness parameter Z0. Using exchange coefficients of individual bean leaves (Thom 1968) and the bulk momentum absorption properties of a particular bean crop (Thom 1971) the relation B−1 = (constant) u*1/3 is derived. With u* in cm s−1, the constant is 1.35 for heat exchange and transpiration, 2.18 for CO2 exchange, and 1.13 for evaporation from the crop when wet. It is suggested, partly on the basis of the lack of dependence of B−1 on z0, that the same set of equations may provide a first approximation to B−1 for many types of vegetation. Demonstrated are (i) that Monteith's (1963) method of extrapolating to zero wind speed to determine representative surface values of vapour pressure and of temperature (es and Ts) is much more rigorous if extrapolation is made to u = −B−1u* rather than to u = 0; and (ii) that the surface resistance γS, proportional to (ew(Ts) − es) (Monteith 1965) exceeds the bulk physiological, or stomatal, resistance γST of vegetation by an amount {1 − (Δ/γ).β}.B−1/u*, significant only when the Bowen ratio β is less than about 3/4(γ/Δ). (γ = 0.66 mb °C−1; Δ = dew/dT.) In particular, for B−1 = 4 and β = 0: (i) γST = 1/3 to 1/2 of γS; and (ii) use of γS with γD in the Penman equation (instead of γS, with which γD is compatible) overestimates λE by about 15 per cent.

1997 - IEEE Trans. Geosci. Remote. Sens.

Estimation of bare surface soil moisture and surface roughness parameter using L-band SAR image data

An algorithm based on a fit of the single-scattering integral equation method (IEM) was developed to provide estimation of soil moisture and surface roughness parameter (a combination of rms roughness height and surface power spectrum) from quad-polarized synthetic aperture radar (SAR) measurements. This algorithm was applied to a series of measurements acquired at L-band (1.25 GHz) from both AIRSAR (Airborne Synthetic Aperture Radar operated by the Jet Propulsion Laboratory) and SIR-C (Spaceborne Imaging Radar-C) over a well-managed watershed in southwest Oklahoma. Prior to its application for soil moisture inversion, a good agreement was found between the single-scattering IEM simulations and the L-band measurements of SIR-C and AIRSAR over a wide range of soil moisture and surface roughness conditions. The sensitivity of soil moisture variation to the co-polarized signals were then examined under the consideration of the calibration accuracy of various components of SAR measurements. It was found that the two co-polarized backscattering coefficients and their combinations would provide the best input to the algorithm for estimation of soil moisture and roughness parameter. Application of the inversion algorithm to the co-polarized measurements of both AIRSAR and SIR-C resulted in estimated values of soil moisture and roughness parameter for bare and short-vegetated fields that compared favorably with those sampled on the ground. The root-mean-square (rms) errors of the comparison were found to be 3.4% and 1.9 dB for soil moisture and surface roughness parameter, respectively.

2006 - Strategic Organization

Does experience matter? The effect of founding team experience on the survival and sales of newly founded ventures

While earlier researchers have argued that the founding team’s industry and start-up experience should positively affect new venture performance, robust empirical support for these arguments has been lacking. Moreover, theory suggests that the relationship between founding team experience and new venture performance may be more complex than previous empirical research suggests. We test specific hypotheses about the effect of founding team industry and start-up experience on the survival and sales of 223 new ventures initiated by a representative sample of Swedish new ventures, using a methodology that overcomes the limitations to previous research. Our results show that founding team experience enhances both new venture survival and sales, but that the effects are non-lin ear, and vary with venture age.

1989 - Journal of Materials Research

Analytic embedded atom method model for bcc metals

The requirements for fitting bcc metals within the EAM format are discussed and, for comparative purposes, the EAM format is cast in a normalized form. A general embedding function is defined and an analytic first- and second-neighbor model is presented. The parameters in the model are determined from the cohesive energy, the equilibrium lattice constant, the three elastic constants, and the unrelaxed vacancy formation energy. Increasing the elastic constants, increasing the elastic anisotropy ratio, and decreasing the unrelaxed vacancy formation energy favor stability of a close-packed lattice over bcc. A stable bcc lattice relative to close packing is found for nine bcc metals, but this scheme cannot generate a model for Cr because the elastic constants of Cr require a negative curvature of the embedding function.

1981 - Proceedings of the Royal Society of London. A. Mathematical and Physical Sciences

An experimental investigation of fluid flow resulting from the impact of a water drop with an unyielding dry surface

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The flow of fluid associated with the impact of water drops of radius R at a speed V onto unyielding dry metal surfaces of known roughness Ra is described. Spatial dimensions of the deforming drop are normalized by transformations of the kind x' — x/R, and time scales are normalized according to t' = tV/R, to permit comparison of events where or differ. It is shown that the primary influence of the surface roughness parameter Ra is the determination of the condition for the ejection of secondary droplets by the excitation of an instability in the developing watersheet; provided Ra≪ R, it is possible to evaluate the condition to a high degree of accuracy, and for Ra = 0.84 μm it is found to be α4/3RV1.69 > 7.4, where α is the eccentricity of the drop at the moment of impact. Deceleration of the drop apex does not commence until > 0.6, contrary to the prediction of Engel (1955) but in good agreement with that of Savic & Boult (1957). Close examination of the very early stages of impact suggests strongly that the so-called watersheet originates at a moment t' — 0.01 after first contact, regardless of the absolute values of R, V or Ra; the initial normalized watersheet velocity is of order 5. Where there is ejected material, its normalized velocity at the moment of ejection is of the order of 20 % greater than that of the watersheet substrate. Simple calculations also suggest that initial fluid velocities greater than 10 are required immediately before the initiation of the watersheet (t'< 0.01). Impacts at speeds considerably greater than the appropriate terminal fall speed in air show no deviations in character from those investigated at much lower speeds. A simple subsidiary experiment also suggests that greater impact velocities are required to produce splashing on inclined targets.

1987 - American Journal of Sociology

The Ecology of Organizational Founding: American Labor Unions, 1836-1985

This paper analyzes the founding rate of national labor unions in the United States for the period 1836-1985. It investigates the effects of competitive processes and environmental effects on this rate. A number of stochastics models embodying different assumptions about the ecology of foundings are estimated. The best-fitting models posit that the effect of density (the number of unions in existence) and the number of recent foundings on the foundig rate is curvilinear. Analysis of more complicated models reveals that the growth of industrial unions inhibited the founding rate of craft unions. However, the founding rate of industrial unions was unaffected by the number of craft unions in existence.

2013 - Reviews of Modern Physics

Spinor Bose gases: Symmetries, magnetism, and quantum dynamics

Spinor Bose gases form a family of quantum fluids manifesting both magnetic order and superfluidity. This article reviews experimental and theoretical progress in understanding the static and dynamic properties of these fluids. The connection between system properties and the rotational symmetry properties of the atomic states and their interactions are investigated. Following a review of the experimental techniques used for characterizing spinor gases, their mean-field and many-body ground states, both in isolation and under the application of symmetry-breaking external fields, are discussed. These states serve as the starting point for understanding low-energy dynamics, spin textures and topological defects, effects of magnetic dipole interactions, and various non-equilibrium collective spin-mixing phenomena. The paper aims to form connections and establish coherence among the vast range of works on spinor Bose gases, so as to point to open questions and future research opportunities.

1999 - Entrepreneurship Theory and Practice

Founding Family Control and Capital Structure: The Risk of Loss of Control and the Aversion to Debt

This paper tests the hypothesis that Founding Family Controlled Firms (FFCFs) are more averse to control risk than similar non-FFCFs and therefore avoid debt. Higher levels of debt increase the likelihood of bankruptcy and the level of control risk. We show that FFCFs use less debt; their choice of debt is more sensitive to conditions associated with control risk; and that leverage is not significantly related to managerial ownership in non-FFCFs, indicating that founding family control, not managerial ownership, matters in determining leverage.

2008 - Organ. Sci.

Founding the Future: Path Dependence in the Evolution of Top Management Teams from Founding to IPO

We contrast life-cycle and path-dependent views of entrepreneurial firms by examining the evolution of top management teams. We show how initial conditions constrain subsequent outcomes by demonstrating that the founding team's prior functional experiences and initial organizational functional structures predict subsequent top manager backgrounds and later functional structures. We find that narrowly experienced teams have trouble adding functional expertise not already embodied in the team. We also find that firms beginning with a limited range of functional positions are less likely to develop complete functional structures. Importantly, we do not find functional structure and functional experience to be interchangeable. We find that firms beginning with more complete functional structures are likely to go public faster, and firms beginning with broadly experienced team members obtain venture capital more quickly regardless of the experience and structural composition of the top management team in place at the time of these outcomes. Further, broadly experienced founding teams that build an early team with a full complement of functional positions achieve important milestones faster than firms that start with neither experience nor structure. This suggests that creating positions as “placeholders” in new ventures, where positions are created and filled with the intent of bringing individuals with more relevant experience onboard later, is not obviously a path by which to succeed. By examining the origins of top management team experience and functional structures, we illustrate the lasting imprint of founders on top management team composition and firm outcomes.


Contributions to the Founding of the Theory of Transfinite Numbers

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Dear readers, when you are hunting the new book collection to read this day, contributions to the founding of the theory of transfinite numbers dover books on mathematics can be your referred book. Yeah, even many books are offered, this book can steal the reader heart so much. The content and theme of this book really will touch your heart. You can find more and more experience and knowledge how the life is undergone.

2005 - PLoS biology

On the Number of New World Founders: A Population Genetic Portrait of the Peopling of the Americas

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The founding of New World populations by Asian peoples is the focus of considerable archaeological and genetic research, and there persist important questions on when and how these events occurred. Genetic data offer great potential for the study of human population history, but there are significant challenges in discerning distinct demographic processes. A new method for the study of diverging populations was applied to questions on the founding and history of Amerind-speaking Native American populations. The model permits estimation of founding population sizes, changes in population size, time of population formation, and gene flow. Analyses of data from nine loci are consistent with the general portrait that has emerged from archaeological and other kinds of evidence. The estimated effective size of the founding population for the New World is fewer than 80 individuals, approximately 1% of the effective size of the estimated ancestral Asian population. By adding a splitting parameter to population divergence models it becomes possible to develop detailed portraits of human demographic history. Analyses of Asian and New World data support a model of a recent founding of the New World by a population of quite small effective size.

2003 - Industrial and Corporate Change

Bringing individuals back in: the effects of career experience on new firm founding

Because of methodological and theoretical obstacles, research on organizational foundings has largely focused on societal and population-level explanations. This paper takes the view that understanding firm foundings also requires linking to individual-level processes. We suggest that careers are an important mechanism linking individual-level processes to firm foundings. The firm-founding experience of potential founders impacts organizational foundings by influencing expectations of the liability of newness. We test our explanation on the set of inventions patented by the Massachusetts Institute of Technology over the period 1980--1996 by examining the effect of inventors' career experiences on the likelihood that an invention will be commercialized through the founding of a new organization. Copyright 2003, Oxford University Press.

2000 - Design Studies

Sources of inspiration: a language of design

Sources of inspiration play an important role in the design process, both in defining the context for new designs and in informing the creation of individual designs. Previous designs and other sources of ideas furnish a vocabulary both for thinking about new designs and for describing designs to others. In a study of knitwear design, a process in which the use of sources of inspiration is explicitly acknowledged, we have observed that designers communicate with each other about new designs, styles and moods, largely by reference to the sources of their ideas. In this paper we discuss why this style of communication is so important, and what information it is used to convey. We view it as the use of a language to describe regions in the space of possible designs.

2010 - Biomaterials

The influence of nano-scale surface roughness on bacterial adhesion to ultrafine-grained titanium.

We discuss the effect of extreme grain refinement in the bulk of commercial purity titanium (CP, Grade-2) on bacterial attachment to the mechano-chemically polished surfaces of the material. The ultrafine crystallinity of the bulk was achieved by severe plastic deformation by means of equal channel angular pressing (ECAP). The chemical composition, wettability, surface topography and roughness of titanium surfaces were characterized using X-ray photoelectron spectroscopy (XPS) and water contact angle (WCA) measurements, as well as atomic force microscopy (AFM) with 3D interactive visualization of the titanium surface morphology. It was found that physico-chemical surface characteristics of the as-received and the ECAP-modified CP titanium did not differ in any significant way, while the surface roughness at the nano-scale did. Optical profilometry performed on large scanning areas of approximately 225 mum x 300 mum showed that there was no significant difference between the roughness parameters R(a) and R(q) for surfaces in the two conditions, the overall level of roughness being lower for the ECAP-processed one. By contrast, topographic profile analysis at the nano-scale by AFM did reveal a difference in these parameters. This difference was sensitive to the size of the scanned surface area. A further two surface roughness parameters, skewness (R(skw)) and kurtosis (R(kur)), were also used to describe the morphology of titanium surfaces. It was found that the bacterial strains used in this study as adsorbates, viz. Staphylococcus aureus CIP 65.8 and Pseudomonas aeruginosa ATCC 9025, showed preference for surfaces of ECAP-processed titanium. S. aureus cells were found to have a greater propensity for attachment to surfaces of ECAP-modified titanium, while the attachment of P. aeruginosa, while also showing some preference for the ECAP-processed material, was less sensitive to the ECAP processing.

Paper Keywords

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