Evaluation of Red Colour Segmentation Algorithms in Traffic Signs Detection

Colour segmentation is the most commonly used method in road signs detection. Road sign contains several basic colours such as red, yellow, blue and white which depends on countries.The objective of this thesis is to do an evaluation of the four colour segmentation algorithms. Dynamic Threshold Algorithm, A Modification of de la Escalera’s Algorithm, the Fuzzy Colour Segmentation Algorithm and Shadow and Highlight Invariant Algorithm. The processing time and segmentation success rate as criteria are used to compare the performance of the four algorithms. And red colour is selected as the target colour to complete the comparison. All the testing images are selected from the Traffic Signs Database of Dalarna University [1] randomly according to the category. These road sign images are taken from a digital camera mounted in a moving car in Sweden.Experiments show that the Fuzzy Colour Segmentation Algorithm and Shadow and Highlight Invariant Algorithm are more accurate and stable to detect red colour of road signs. And the method could also be used in other colours analysis research. The yellow colour which is chosen to evaluate the performance of the four algorithms can reference Master Thesis of Yumei Liu.

Modification of jet shapes in PbPb collisions at root s(NN)=2.76 TeV

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Insulated retroviral vectors towards safe and efficient genetic modification of stem cells

In otherwise successful gene therapy trials for the treatment of SCID patients and others, insertional mutagenesis has resulted in leukemia development. Besides the integration of vectors that including strong enhancers, more recently, SIN-vectors have been shown to partially retain oncogenic potential. The identification of genetic elements which would both prevent such activation effects and shield the transgene from silencing, is a main challenge. Previous attempts met with difficulties in producing the vectors and poor efficacy of the insulators (GIE). The improvement of integrating vectors safety has been investigated using new candidate synthetic GIEs. The latter have been introduced in retroviral and lentiviral vectors. Native LTRs, SIN-LTRs, and SIN-insulated constructs have been designed and compared, using two sets of internal promoter, i.e. strong and housekeeping. We could establish that a specific insulator translates at best into functional activity and boundary effect in both vector types. We could also determine that other genetic elements are key determinants in order to achieve accurate expression and viral titre, from these insulated vectors. A dramatic shift in the expression profile is observed in target cells, with a homogenous pattern including data on both cell-lines and primary HSCs from cord blood. The assessment of potential genotoxicity will be presented, based on the comparison of the integration patterns ingenuity in human target cells sampled over a three months period with both reference LTRs and SIN versus test insulated vectors, using high-throughput pyro-sequencing.

Modification of the Perrine-Baum diagram to improve the calculation of high voltage electric lines

Through the history of Electrical Engineering education, vectorial and phasorial diagrams have been used as a fundamental learning tool. At present, computational power has replaced them by long data lists, the result of solving equation systems by means of numerical methods. In this sense, diagrams have been shifted to an academic background and although theoretically explained, they are not used in a practical way within specific examples. This fact may be against the understanding of the complex behavior of the electrical power systems by students. This article proposes a modification of the classical Perrine-Baum diagram construction to allowing both a more practical representation and a better understanding of the behavior of a high-voltage electric line under different levels of load. This modification allows, at the same time, the forecast of the obsolescence of this behavior and line’s loading capacity. Complementary, we evaluate the impact of this tool in the learning process showing comparative undergraduate results during three academic years

On the efficiency and sensitivity of a pyramidal classification algorithm

In this paper we propose a Pyramidal Classification Algorithm,which together with an appropriate aggregation index producesan indexed pseudo-hierarchy (in the strict sense) withoutinversions nor crossings. The computer implementation of thealgorithm makes it possible to carry out some simulation testsby Monte Carlo methods in order to study the efficiency andsensitivity of the pyramidal methods of the Maximum, Minimumand UPGMA. The results shown in this paper may help to choosebetween the three classification methods proposed, in order toobtain the classification that best fits the original structureof the population, provided we have an a priori informationconcerning this structure.

Multiple correspondence analysis of a subset of response categories

In the analysis of multivariate categorical data, typically the analysis of questionnaire data, it is often advantageous, for substantive and technical reasons, to analyse a subset of response categories. In multiple correspondence analysis, where each category is coded as a column of an indicator matrix or row and column of Burt matrix, it is not correct to simply analyse the corresponding submatrix of data, since the whole geometric structure is different for the submatrix . A simple modification of the correspondence analysis algorithm allows the overall geometric structure of the complete data set to be retained while calculating the solution for the selected subset of points. This strategy is useful for analysing patterns of response amongst any subset of categories and relating these patterns to demographic factors, especially for studying patterns of particular responses such as missing and neutral responses. The methodology is illustrated using data from the International Social Survey Program on Family and Changing Gender Roles in 1994.

Implementation of the Rijndael-AES algorithm on a Sage-Math worksheet

La principal motivació d'aquest treball ha estat implementar l'algoritme Rijndael-AES en un full Sage-math, paquet de software matemàtic de lliure distribució i en actual desenvolupament, aprofitant les seves eines i funcionalitats integrades.

Modification of personality variables through application of a psycho-educational program of full consciousness (mindfulness) in university students

This study examines the effects in university students of a psycho-educational program in full awareness (mindfulness) on certain personality variables. A quasi-experimental (group comparison) design with pretest and postest measurements was employed in an experimental (n = 26) and a control group (n = 27). Barratt impulsiveness Scale (BiS- 11), Acceptance and Action Questionnaire (AAQ), Social Avoidance and Distress Scale (SAD), and the Profile of Mood States (POMS) were applied to experimental and control groups. The results show statistically significant changes in impulsivity variables, experiential avoidance, social avoidance, social anxiety, tension and fatigue when comparing the posttest mean scores of the groups.

From DNA to GM wheat : discovering genetic modification of food.

Para que los estudiantes desarrollen habilidades en la lectura de textos de no ficción. En esta colección se exponen los avances, inventos y descubrimientos de la ciencia , y cómo un descubrimiento o la invención de una persona puede dar lugar a una serie de descubrimientos hechos por los demás, e incluso una cadena de descubrimientos científicos. Este título proporciona una visión general del ADN. Se describe cómo se descubrió, la investigación realizada sobre los genes, por qué las plantas y los animales son genéticamente modificados, y los pros y los contras de usar esta forma de la biotecnología. Tiene relación cronológica de descubrimientos, unas breves biografías de los científicos clave en sus respectivos campos, glosario y bibliografía.

Construction and modification of the autonomy of school mathematical knowledge in Portugal

Resumen basado en el de la publicaci??n

Modification of radiation pressure due to cooperative scattering of light

Cooperative spontaneous emission of a single photon from a cloud of N atoms modifies substantially the radiation pressure exerted by a far-detuned laser beam exciting the atoms. On one hand, the force induced by photon absorption depends on the collective decay rate of the excited atomic state. On the other hand, directional spontaneous emission counteracts the recoil induced by the absorption. We derive an analytical expression for the radiation pressure in steady-state. For a smooth extended atomic distribution we show that the radiation pressure depends on the atom number via cooperative scattering and that, for certain atom numbers, it can be suppressed or enhanced. Cooperative scattering of light by extended atomic clouds can become important in the presence of quasi-resonant light and could be addressed in many cold atoms experiments.

Modification of the industrialization model in Latin America

Esboza los trazos principales de interpretacion del proceso de industrializacion desde la decada de los anos 30 hasta el presente. Aborda el tema central de la transformacion del modelo hasta ahora predominante de industrializacion. Propone una estrategia industrial basada en el crecimiento hacia adentro, mediante la creacion de industrias de bienes de capital y de consumo masivo, la continuacion del proceso de sustitucion selectiva de importaciones, el establecimiento de criterios claros de division del trabajo dentro de la region, y la aplicacion de una politica selectiva y dinamica de insercion en los mercados de los paises centrales.

Electrochemical surface modification of Single walled carbon nanotubes and graphene-based electrodes for (bio)sensing applications

Sensors are devices that have shown widespread use, from the detection of gas molecules to the tracking of chemical signals in biological cells. Single walled carbon nanotube (SWCNT) and graphene based electrodes have demonstrated to be an excellent material for the development of electrochemical biosensors as they display remarkable electronic properties and the ability to act as individual nanoelectrodes, display an excellent low-dimensional charge carrier transport, and promote surface electrocatalysis. The present work aims at the preparation and investigation of electrochemically modified SWCNT and graphene-based electrodes for applications in the field of biosensors. We initially studied SWCNT films and focused on their topography and surface composition, electrical and optical properties. Parallel to SWCNTs, graphene films were investigated. Higher resistance values were obtained in comparison with nanotubes films. The electrochemical surface modification of both electrodes was investigated following two routes (i) the electrografting of aryl diazonium salts, and (ii) the electrophylic addition of 1, 3-benzodithiolylium tetrafluoroborate (BDYT). Both the qualitative and quantitative characteristics of the modified electrode surfaces were studied such as the degree of functionalization and their surface composition. The combination of Raman, X-ray photoelectron spectroscopy, atomic force microscopy, electrochemistry and other techniques, has demonstrated that selected precursors could be covalently anchored to the nanotubes and graphene-based electrode surfaces through novel carbon-carbon formation.

Eutectic modification of Al-Si alloys with rare earth metals

The effects of different concentrations of individual additions of rare earth metals (La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu) on eutectic modification in Al-10mass%Si has been studied by thermal analysis and optical microscopy. According to the twin-plane re-entrant edge (TPRE) and impurity induced twinning mechanism, rare earth metals with atomic radii of about 1.65 times larger than that of silicon, are possible candidates for eutectic modification. All of the rare earth elements caused a depression of the eutectic growth temperature, but only Eu modified the eutectic silicon to a fibrous morphology. At best, the remaining elements resulted in only a small degree of refinement of the plate-like silicon. The samples were also quenched during the eutectic arrest to examine the eutectic solidification modes. Many of the rare-earth additions significantly altered the eutectic solidification mode from that of the unmodified alloy. It is concluded that the impurity induced twinning model of modification, based on atomic radius alone, is inadequate and other mechanisms are essential for the modification process. Furthermore, modification and the eutectic nucleation and growth modes are controlled independently of each other.