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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

O Trabalho no Amazonas: o periódico Tribuna Popular como instrumento de “orientação das hostes trabalhistas”

Pio Junior, Amaury Oliveira, 92-98243-5574 15 September 2016 (has links)
Submitted by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2018-03-27T15:12:32Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertação_Amaury O. Pio Junior.pdf: 2560693 bytes, checksum: d9d64d08efd20ddb4af66fdf8e8a3a23 (MD5) / Approved for entry into archive by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2018-03-27T15:12:44Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertação_Amaury O. Pio Junior.pdf: 2560693 bytes, checksum: d9d64d08efd20ddb4af66fdf8e8a3a23 (MD5) / Made available in DSpace on 2018-03-27T15:12:44Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertação_Amaury O. Pio Junior.pdf: 2560693 bytes, checksum: d9d64d08efd20ddb4af66fdf8e8a3a23 (MD5) Previous issue date: 2016-09-15 / This thesis aims to analyze the process of Workforce Movement's emergence and elaboration in Amazonas in early 1930s. This period was characterized by the rise of Getulio Vargas as president of the provisional Government. Amazonas, in this context, lived the reordering of its political forces. The fading of the oligarchic system, gave oppotunity to the projection of a new regional political leadership of Vargas' projects. At the same time, we were living important changes in the relationship between governments and unions, indicated by the foundation of the Ministry of Labor, Industry and Commerce in late 1930. Since then, the union movement becomes better observed by some political leaders who, in Amazonas, came to align themselves with this segment, and in some cases, acted as agents of Vargas policy with workers' organizations. In this context, some leaders such as Álvaro Botelho Maia and Luís Tirelli begin to stand out in the local political context. The Partido Socialista Amazonense (PSA) and the Partido Trabalhista Amazonense (PTA) respectively, their performances were extremely important in aggregating the main political forces of that period in Amazonas. Their performances in the elections of 1933, 1934 and 1935 highlighted as political party agents, at first in antagonistic positions, and then, under one party - Partido Popular Amazonense - (PPA) - became allies of the Getulio Vargas' proposals. In this scenario, Tribuna Popular newspaper's foundation, first as the PTA disclosure institution and subsequently linked to the PPA, is revealed as an important information source in that period, and the aforementioned party leaders. Its periodicity between 1933 and 1936, not only allows to build the constitution of the political Amazonas profile, but also alert us to their other function, which was to offer itself as a place for the labor proposals draft their proposals, concerns and discussions about some of the people involved in the workforce and trade union world at that time. / Esta dissertação tem por objetivo analisar o processo de surgimento e gestação do Movimento Trabalhista no Estado do Amazonas, por volta da primeira metade da década de 1930. Esse período seria caracterizado pelos desdobramentos, em todo país, da ascensão de Getúlio Vargas como presidente do então Governo Provisório. O Amazonas, sob tal contexto, assistiria ao reordenamento de suas forças políticas. O enfraquecimento do sistema oligárquico oportunizaria a projeção de novas lideranças políticas regionais que, naquele momento, colocavam-se à disposição dos projetos pretendidos por Vargas. Ao mesmo tempo, vivenciaríamos ali importantes transformações nas relações entre governos e sindicatos, indicadas pela criação do Ministério do Trabalho, Indústria e Comércio em fins de 1930. A partir de então, o movimento sindical passa a ser melhor observado por algumas lideranças políticas que, no caso do Amazonas, alinham-se com esse segmento, chegando, em alguns casos, a atuarem como agentes da política varguista junto às organizações de trabalhadores. Nesse contexto, algumas lideranças como Álvaro Botelho Maia e Luís Tirelli passam a destacar-se no quadro político local. À frente do Partido Socialista Amazonense (PSA) e do Partido Trabalhista Amazonense (PTA), respectivamente, suas atuações foram fundamentais em agregarem em torno de si as principais forças políticas daquele período no Estado. Seus desempenhos nos processos eleitorais de 1933, 1934 e 1935 destacaram-nos enquanto agentes político-partidários, num primeiro momento em posições antagônicas para, logo em seguida, sob uma única legenda – o Partido Popular Amazonense (PPA) - seguirem como aliados em torno das propostas de Getúlio Vargas. Em meio a esse cenário, a fundação do periódico Tribuna Popular, primeiro como órgão de divulgação do PTA e, posteriormente, vinculado ao PPA, revela-se como uma fonte primorosa sob o período e as lideranças partidárias acima mencionadas. Sua periodicidade entre os anos de 1933 e 1936, além de permitir traçar a constituição do perfil político do Amazonas, desperta-nos para sua outra função, que era oferecer-se enquanto espaço para que as propostas Trabalhistas pudessem, ao longo desses anos, esboçarem suas propostas, anseios e discussões sobre parte do mundo operário e sindical da época.
22

Caracterización de Recubrimientos Depositados por Proyección Térmica de Alta Velocidad y Aportes de Soldaduras PTA

Carrasco Contreras, Jorge Patricio January 2010 (has links)
La creciente demanda de la industria por disponer de recubrimientos de alta resistencia a la corrosión y abrasión con un menor costo, induce el desarrollo de nuevos compuestos con menor rugosidad superficial y mayor adherencia al substrato. El desgaste abrasivo es uno de los grandes problemas que se presentan en piezas que trabajan en contacto con minerales. Las técnicas de proyección térmica y soldadura PTA, son usadas para formar recubrimientos duros y se basan en conferir al material a depositar (en forma de polvo o varilla), suficiente energía térmica con tal de proyectar material fundido o parcialmente fundido con alta energía cinética formando un recubrimiento compacto. El estudio que se presenta a continuación tiene su origen en la observación del desgaste prematuro en asientos de válvulas API-9 de bombas GEHO ZPM Duplex presentes en la minería del cobre, las cuales sufren desgaste por abrasión y son reemplazadas cada apróx. 800 [h]. El objetivo del trabajo es producir recubrimientos duros, determinar la influencia de la composición y micro-estructura en el comportamiento en desgaste y micro-dureza y comparar los resultados con el material presente en dicha válvula. Se fabricaron 4 probetas de acero SAE 1020 de dimensiones 50x50x10 [mm], dos de ellas con recubrimientos metálicos; base niquel (Durmat 59 PTA), base hierro (Durmat 505 PTA), y dos con recubrimientos cerámicos una mezcla niquel y carburo de tungsteno (Durmat 62 PTA), y una con Carburo de tungsteno-Cobalto (Durmat 101 PTA). Se hizo Microscopía Óptica, se sometieron a ensayo de desgaste ASTM-G65 procedimiento A, microscopía electrónica de barrido (SEM) y Micro-dureza. Los resultados arrojaron que Durmat 101 HVOF pierde un 65 % menos de peso y un 32% menos de espesor frente al material de la válvula. Además este recubrimiento es un 68 % más duro que la válvula, con un valor promedio de 1341,8 HV03,. Es el único recubrimiento que obtiene mejores resultados que el material de la válvula. El 59 PTA muestra un crecimiento dendrítico fino en la microscopía, y al agregar carburos de tungsteno la resistencia al desgaste mejora y la dureza aumenta en un 31%. El 505 PTA tiene una micro-estructura muy fina y compacta, con carburos finos ordenados en una matriz de hierro. De los recubrimientos aportados por soldadura de arco transferido, fue el de mejor desempeño. El recubrimiento metálico base Níquel, Durmat 59 PTA, es el que presenta el comportamiento más deficiente en todas las pruebas y es el único que en el ensayo de desgaste llegó al material base.
23

Characterization of a newly developed martensitic stainless steel powder for Laser and PTA cladding

Tibblin, Fritjof January 2015 (has links)
A newly developed martensitic stainless steel powder, called “powder A”, designed for surface coating with laser cladding and PTA cladding was characterized. The purpose with powder A is to achieve both good corrosion resistance and wear resistance in a stainless steel grade. The investigation of powder A was divided into cladding characterization, microstructural investigation and a property comparison to existing grades 316 HSi and 431 L. Powder A was successfully deposited with laser cladding, exhibiting a wide process window, and PTA cladding. In both cases no preheating was required and no cracks were formed. The microstructure examination indicates that powder A has a martensitic structure possibly containing small amounts of ferrite in the grain boundaries. Thermodynamic calculations in computer software Thermo-Calc 4.1 supported this theory. The microstructure of powder A proved to be very stable over a wide range of cladding parameters. Powder A was significantly harder than 316 HSi and 431 L and had better corrosion resistance than 431 L in a chloride environment. Powder A had similar corrosion properties as 316 HSi in the experiments made .The wear performance of the powder A coatings was similar to 431 L. This was surprising since the hardness of the powder A coatings is significantly higher compared to 431 L.
24

An assessment of the implications of agoa on the South African poultry industry

April, Zuko January 2021 (has links)
Philosophiae Doctor - PhD / As a signatory to the African Growth and Opportunity Act (AGOA) agreement, a preferential trade agreement (PTA) with the United States, South Africa derives several benefits. PTAs grant access to certain products from developing countries and, while the tariffs are sometimes not completely removed, the tariffs charged are far less than those imposed on countries that are not included in the trade agreement. There is strong evidence that PTAs increase trade and investment between member countries. South African exports of goods and services to the US under AGOA have increased by 104% since 2000. While PTAs seem to benefit developing countries at the aggregate level, not much is known about the winners and losers from preferential trade liberalisation at the level of the firm. This study assessed the PTA benefits of AGOA at the firm level within the South African poultry sector. / 2023
25

Sentiment Analysis for E-book Reviews on Amazon to Determine E-book Impact Rank

Alsehaimi, Afnan Abdulrahman A 18 May 2021 (has links)
No description available.
26

Impact of sire PTA<SUB>SCS</SUB> on mastitis resistance and measures of daughter performance

Cranford, Jamie Layne 04 May 1999 (has links)
Research to determine the impact of PTA<SUB>SCS</SUB> on incidence of mastitis, daughter response to infection, and other measures of daughter performance was conducted using data on 1st, 2nd, and 3rd lactation Holsteins obtained from the Virginia Tech herd and from VA DHI herds. Overall correlation of PTA<SUB>SCS</SUB> to lactation average SCS ranged from 0.13 to 0.17 across all data sets. Correlations between PTA<SUB>SCS</SUB> and 1st lactation SCS measures were higher than those between PTA<SUB>SCS</SUB> and SCS in later parities, but higher correlations were found between 2nd and 3rd lactation SCS measures than between 1st and later parities. Correlation of lactation average SCS and incidence of clinical mastitis was 0.41. Regression of lactation average SCS and averages of test day SCS measures on PTA<SUB>SCS</SUB> was significant in 1st, 2nd, and 3rd lactations. All significant relationships were linear and equal or close to 1.0. Relationships between PTA<SUB>SCS</SUB> and number of cases of clinical mastitis (.79), number of treatments (2.0), number of days treated (7.0), changes in SCS from beginning to end of a lactation (-.26), and the slope of changes in test day SCS with DIM (5.9x10-4) were significant only in 1st lactation. No significant relationships between PTA<SUB>SCS</SUB> and measures of clinical mastitis or variation in test day SCS measures were found in 2nd or 3rd lactations. Heavy cull rates imposed on 1st lactation cows in the Virginia Tech herd explained lack of significance in the later parities in the herd study, but results in following analyses indicated that measures of SCS in 1st and later parities may be two different, but correlated, traits. The greatest impact of PTA<SUB>SCS</SUB> on measures of daughter performance and profit was the negative relationship between PTA<SUB>SCS</SUB> and herd life. Increased PTA<SUB>SCS</SUB> resulted in the decreased ability to survive involuntary culling, and thus decreased opportunity for lifetime yield and profit. Selection on PTA<SUB>SCS</SUB> should be an effective method of reducing incidence of clinical mastitis, lactation average SCS, and variation in SCS, or response to infection. The response, however, may be different in 1st lactation than in later parities. / Master of Science
27

Analyse des stratégies d’évaluation des technologies des corps policiers canadiens : le cas de l’Identité Judiciaire

Beaudoin, Alexandre 12 1900 (has links)
No description available.
28

Analyse des stratégies d’évaluation des technologies des corps policiers canadiens : le cas de l’Identité Judiciaire

Beaudoin, Alexandre 12 1900 (has links)
Les innovations technologiques pullulent dans le milieu policier depuis quelques années. Devant cette abondance de choix technologiques, et dans une conjoncture de ralentissement économique, la police doit s’assurer de faire une sélection favorisant le meilleur retour sur investissement. L’évaluation des technologies est la meilleure méthode permettant d’atteindre cet objectif. Ce projet de recherche analyse les différentes stratégies d’évaluation des technologies des corps policiers fédéraux et provinciaux du Canada en se basant sur le domaine baromètre de l’identité judiciaire. Cette étude s’appuie sur plusieurs données qualitatives : 1) observation participative à la Sûreté du Québec; 2) entrevues semi-directives (n=11) avec des membres de l’Ontario Provincial Police et de la Gendarmerie Royale du Canada. L’analyse intégrée des données colligées permet de mieux comprendre la dynamique de l’évaluation technologique dans la police. Même si une évolution est perceptible, certaines améliorations pourraient accroître l’efficacité du mini-PTA (Police Technology Assessment) dans un contexte où l’opérationnel et le théorique doivent cohabiter en parfaite harmonie afin de faciliter le travail des utilisateurs. Le mini-PTA est un outil facilitant l’adaptation de l’évaluation des technologies aux réalités régionales, mais ne peut en aucun cas remplacer unilatéralement le PTA fait par les grosses organisations d’évaluation des technologies policières. / Law enforcement has seen a proliferation of technological innovation in recent years. At the same time, the global recession has reduced the fiscal resources available to purchase and deploy new technological solutions. Thus, it is imperative that police forces select the technologies that offer a high return on investment. The technology assessment is the best method for achieving this goal. This research project analyzes different strategies of technology assessment employed by Forensic Identification units in federal and provincial police forces of Canada. This qualitative study is based on: 1) participant observations at the Surete du Quebec and 2) semi-structured interviews (n=11) with members of the Ontario Provincial Police and the Royal Canadian Mounted Police. An integrated analysis of the study data offers new insight into the dynamics of technology assessment as currently employed in the police force. The current practices strive to maximize return on investment. Nevertheless, there are refinements that will increase the efficiency of mini-PTA (Police Technology Assessment) and harmonize the operational and theoretical needs required to facilitate the end users' job functions. Even with improvement, the mini-PTA is best suited for smaller, regional police forces. It cannot replace unilaterally the process of PTA conducted by large police technology assessment agencies.
29

Avaliação da resistência ao desgaste de revestimentos duros aplicados por soldagem em martelos trituradores de baterias automotivas.

SOUSA NETO, Emydio Clemente de. 23 April 2018 (has links)
Submitted by Kilvya Braga (kilvyabraga@hotmail.com) on 2018-04-23T10:51:37Z No. of bitstreams: 1 EMYDIO CLEMENTE DE SOUSA NETO - DISSERTAÇÃO (PPGEM) 2015.pdf: 5264287 bytes, checksum: 48883828373d3daac0f65ee6e1ef7809 (MD5) / Made available in DSpace on 2018-04-23T10:51:37Z (GMT). No. of bitstreams: 1 EMYDIO CLEMENTE DE SOUSA NETO - DISSERTAÇÃO (PPGEM) 2015.pdf: 5264287 bytes, checksum: 48883828373d3daac0f65ee6e1ef7809 (MD5) Previous issue date: 2015-07-31 / O desgaste prematuro de conjuntos e componentes industriais, bem como de uma infinidade de outros segmentos, representa um grande fator para a redução da eficiência operacional de um equipamento, provocando assim, um aumento das perdas, e consequentemente, em altas despesas com manutenção e reposição de componentes mecânicos. Este trabalho aborda uma análise comparativa entre a resistência ao desgaste de martelos trituradores de baterias recuperados por três ligas a base de cobalto (Stellite 1, 6 e 21), bem como dois processos de deposição: os processos ao Arco Elétrico com Eletrodo Revestido (SMAW) e ao Arco Plasma Transferido com adição de Pó (PTA-P). Os martelos trituradores são originalmente confeccionados em aço inoxidável AISI 316 L sem nenhum recobrimento. Além da avaliação da resistência ao desgaste no próprio meio de trabalho foram realizados ensaios de microdureza, análises microestruturais via microscopia ótica, e eletrônica de varredura e, análise de diluição com o objetivo de caracterizar e consolidar a pesquisa para que se tenha o estudo comparativo da melhor liga e melhor processo de deposição. Os resultados demostraram que a melhor condição testada foi aquela que empregou a liga Stellite 6 depositadas pelo processo PTA-P. Essa condição apresentou a menor perda de massa nos ensaios de resistência ao desgaste, enquanto que a condição menos favorável foi verificada para os depósitos executados com a liga Stellite 1 utilizando o mesmo processo de deposição. A diluição média das ligas depositadas pelo processo SMAW foi 3,7 vezes maior do que a média apresentada utilizando o processo PTA-P. Os maiores valores de microdureza foram aqueles apresentados pelo revestimento executados com a liga Stellite 1 com maior teor de C, e esta liga, proporcionou um maior número de destacamento dos revestimentos. A microestrutura dos depósitos executados pelo processo PTA-P apresentou-se mais refinada quando comparada com aquelas depositadas pelo processo SMAW. / The premature wear sets and industrial components, as well as many of other segments, is a big factor for reducing operational efficiency of equipment, thus causing an increase in losses, and consequently in high cost of maintenance and replacement of mechanical components. This work presents a comparative analysis of the wear resistance of AISI 316 L steel automotive batteries crushers hammers repaired by welding process using three cobalt-based alloys: Stellite 1, 6 and 21, as well as, two welding deposition process: Shielded Metal Arc Welding (SMAW) and Plasma Transferred Arc with addition powder (PTA-P). Crushers hammers are originally made of stainless steel AISI 316 L with no coating. Besides the “in situ” wear resistance evaluation microhardness tests, microstructure and dilution analysis by optical microscopy and scanning electron were done to characterize and consolidate research in order to have a comparative study of best league and better deposition process. The results showed that the best alloy was Stellite 6 using the PTA-P process, which had the lowest mass loss in wear resistance tests, while the less favorable condition was for deposits made with the alloy Stellite 1 using the same deposition welding process. The average dilution of the alloys deposited by the SMAW process was 3.7 times higher than the average using the PTA-P process. The highest microhardness values were presented by Stellite 1 alloy deposit, with higher C content, which also provided a greater number of coating detachment. The deposits made by the process PTAP showed a more refined microstructure when compared to those deposited by the SMAW process
30

Simulation et étude expérimentale des contraintes résiduelles dans les dépôts durs Norem des matériels de robinetterie / Modelisation and experimental study of residual stresses in Norem hardfacing coatings used in valve parts

Beaurin, Gauthier 26 June 2012 (has links)
L'intégrité des portées d'étanchéité des robinets des centrales REP nécessite l'emploi de revêtements durs comme par exemple le Norem02, base Fe, déposé par soudage PTA (Plasma Transferred Arc). La prédiction de leur tenue en service nécessite la connaissance de leur état mécanique en fin de fabrication. Pour cela, la simulation numérique du procédé de dépôt doit être effectuée. La microstructure du Norem02 est essentiellement constituée d'une matrice austénitique parsemée d'ilôts de ferrite et de carbures. Son évolution et ses éventuelles transformations allotropiques sont étudiées durant des cycles thermiques représentatifs de ceux subis par le matériau au cours du dépôt, amenant à la conclusion que l'évolution métallurgique de l'alliage n'a que très peu d'influence sur ses propriétés mécaniques. En s'appuyant sur des essais jusqu'à 1000°C de dilatométrie libre, de traction isotherme, ainsi que de traction-compression, l'évolution des caractéristiques thermomécaniques est déterminée en fonction de la température et une loi de comportement élasto-plastique à écrouissage cinématique non linéaire est identifiée. Des mesures expérimentales de températures, déplacements, déformations et contraintes résiduelles lors d'essais de dépôt PTA sur des maquettes représentatives de la géométrie réelle d'un robinet permettent l'identification d'un chargement thermique équivalent. Enfin, des simulations numériques sont conduites en utilisant le code éléments finis développé au sein d'EDF R et D Code_Aster. Elles permettent la validation du caractère prédictif des modèles développés par comparaison entre les résultats mécaniques simulés et expérimentaux. Une excellente corrélation est ainsi observée entre les températures mesurées et simulées tout au long du procédé. De la même façon, à l'issue du refroidissement, les distorsions, déformations et contraintes résiduelles expérimentales et simulées sont en adéquation, validant ainsi la stratégie de modélisation proposée dans ces travaux. / Hardfacing coatings are widely used on the surfaces of parts subjected to drastic loadings. Norem02 alloy, Fe-based, is used in PWR nuclear power plants on valves seating surfaces. Its microstructure consists of a dendritic austenite structure with ferrite islets and carbides. This work tends to demonstrate that for this alloy, metallurgical evolution during the welding process has very little influence on mechanical properties. Tensile behaviour was characterised and completed by dilatometry tests in welding process temperature range until 1000°C, in order to identify an elastoplastic model with non linear kinematic hardening rule. Temperature, displacements, distorsions and residual stresses were measured during the PTAW process and used to identify an equivalent thermal loading by solving an inverse problem. Finally, the numerical simulation of the whole process using the EDF R and D FEM software Code_Aster is presented. Predicted temperatures are consistants with experimental ones. In the same way, predicted displacements, residual distorsions and residual stresses at the end of the cooling phase are close to experimental measures, validating the modelisation strategy presented in this work.

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