Symbol detection in online handwritten graphics using Faster R-CNN

Symbol detection techniques in online handwritten graphics (e.g. diagrams and mathematical expressions) consist of methods specifically designed for a single graphic type. In this work, we evaluate the Faster R-CNN object detection algorithm as a general method for detection of symbols in handwritten graphics. We evaluate different configurations of the Faster R-CNN method, and point out issues relative to the handwritten nature of the data. Considering the online recognition context, we evaluate efficiency and accuracy trade-offs of using Deep Neural Networks of different complexities as feature extractors. We evaluate the method on publicly available flowchart and mathematical expression (CROHME-2016) datasets. Results show that Faster R-CNN can be effectively used on both datasets, enabling the possibility of developing general methods for symbol detection, and furthermore, general graphic understanding methods that could be built on top of the algorithm.Comment: Submitted to DAS-201

Enumerating maximal cliques in link streams with durations

Link streams model interactions over time, and a clique in a link stream is defined as a set of nodes and a time interval such that all pairs of nodes in this set interact permanently during this time interval. This notion was introduced recently in the case where interactions are instantaneous. We generalize it to the case of interactions with durations and show that the instantaneous case actually is a particular case of the case with durations. We propose an algorithm to detect maximal cliques that improves our previous one for instantaneous link streams, and performs better than the state of the art algorithms in several cases of interest

The transition to consumption taxation, part 1: the impact on existing capital

Alan Viard reviews the transitional impact on existing capital from replacing the income tax with a consumption tax. This replacement generally reduces the real value of existing capital because it does not receive the tax relief given to new investment. If the income and consumption taxes had stylized forms and capital were produced without adjustment costs, the proportional decline would equal the consumption tax rate--a 25 percent tax would uniformly reduce the value of existing capital by 25 percent. Under more realistic assumptions, however, the actual decline is likely to be smaller and less uniform and some types of capital may even increase in value. The burden on owners of existing capital is also mitigated because the tax reform increases the rate of return they earn from reinvestment.

Influencia de la formulación del enunciado y del control didáctico sobre la actividad intelectual de los alumnos en la resolución de problemas

Using as reference the scientist instead of the expert for analysing the pupil's behaviour in problem solving, we proposed to students (17 years old) closed and open problems. The great diversity of the students' productions and their analysis in the theoretical framework of didactical contract, oblige us to build two analysis grids: one of the students' activities and the other one for the finalities which we attribute to those activities. We show how ranging the strategy of resolution depends on the text of the problem

Mapping the social space of transnational migrants on the basis of their (supra)national belongings: the case of French citizens in Berlin

In traditional migration theory, social self-identification is usually linked with the process and quality of integration and with the nationality of the countries of ‘origin’ and of residence. But in the context of a supranational integrated area like the European Union, the self-identification of European people living (also) abroad in another European country can be more complicated. What sorts of identity combinations do they produce in this situation? Could we interpret their choice in the light of their social, economic, cultural capitals and (multi)local integration? Based on an empirical analysis of French citizens in Berlin this article confirms that identity self-combining – not just the identity elements – and the position of the ego in the social space are related. The meaning of the same identity category depends on the respondent’s profiles

Convertisseur d'équations LATEX2Ink

International audienceDans cet article nous présentons un outil de génération de formules mathématiques manuscrites en ligne à partir d'une chaîne LATEX. Ce générateur permettra facilement de fabriquer à partir d'un corpus de référence d'expressions mathématiques une base de données qui sera annotée automatiquement au niveau symbole. Ainsi, à partir d'une base de symboles isolés, nous pouvons produire de façon pseudo-synthétique une formule mathématique quelconque par un placement et un dimensionnement stochastiques 2D de ces éléments. Nous montrons l'intérêt de cet outil dans le cadre d'un projet visant à la conception d'une méthode adaptée à la reconnaissance et à l'interprétation d'expressions mathématiques en-ligne

Illegal immigration and enforcement along the U.S.-Mexico border; an overview

Illegal Mexico-U.S. migration has increased dramatically in recent decades. In this article, Pia Orrenius evaluates the causes of this migration and gives an overview of the enforcement and policy responses to date. Orrenius assesses the effectiveness of border enforcement by looking at developments in the smuggling industry, such a smuggler use rates and fees, as well as changes in border-crossing sites. The findings suggest early attempts at enforcement fueled an increase in the demand of and supply of smugglers, with no rise in prices. Only the most recent enforcement initiatives, most significantly Operations Hold-the-Line and Gatekeeper, have been successful in reversing the thirty-year decline in smugglers' fees and moving migrants to remote crossing points. Risks have risen along with smugglers' fees, as reflected in an increasing number of crossing-related deaths since 1995. Orrenius concludes that Mexican and U.S. policymakers should consider a bilateral labor and migration agreement.Labor supply ; Employment (Economic theory)

The Economic and Fiscal Benefits of Pro-Growth Policies

In testimony before the U.S. House Budget Committee, public finance fellow John Diamond outlines steps to reduce projected federal expenditures and reform the U.S. tax system to maximize economic growth

Giochi d'acqua tra invenzione, geografia e memoria letteraria

Sidonio Apollinare come l'uomo tardo antico in generale oscilla nell'esposizione del dato geografico tra una forte tendenza alla referenzialità e la mediazione letteraria. Le descrizioni dei paesaggi d'acqua sono una testimonianza molto interessante della fruizione della letteratura classica e insieme del dato autoptico