Controle de uma microrrede ilhada baseada em geração eólica-diesel com alto nível de inserção de geração eólica

The insertion of distributed generation units in the electric power systems have contributed to the popularization of microgrid concepts. With the microgrids, several potential benefits can be achieved in regard to power quality and supply reliability. However, several technical challenges related to the control and operation of microgrids, which are associated with high insertion of generation systems based on static converters, must be overcame. Among the opportunities in the context of microgrids, there is the islanded operation of microgrids temporarily disconnected from the electric power systems and also the autonomous operation of geographically isolated microgrids. The frequency in large power systems is traditionally controlled by the generation units based on traditional synchronous generator. The insertion of distributed generation units based on static power converters may bring difficulties to the frequency control in microgrids, due to the reduction of the equivalent inertia of conventional synchronous generators present in islanded and isolated microgrids. In this context, it becomes necessary the proposition of new operational and control strategies for microgrids control, taking into account the presence of distributed generation units based on full-rated converter. This paper proposes an operational and control strategy for the islanded operation of a winddiesel microgrid with high insertion level of wind generation. The microgrid adopted in this study comprises of a wind energy conversion system with synchronous generator based on full rated converter, a diesel generator (DIG) and a dump load. Due to the high insertion level of wind generation, the wind unit operates in Vf mode and the diesel generator operates in PQ mode. The diesel generator and the dump load are used to regulate the DC-link voltage of the wind generation unit. The proposed control allows the islanded operation of the microgrid only with wind generation, wind-only mode (WO), and with wind-diesel generation, wind-diesel mode (WD). For the wind-only mode, with 100% of penetration level of wind generation, it is proposed a DC-link voltage control loop based on the use of a DC dump load. For the winddiesel mode, it is proposed a DC-link voltage control loop added to the diesel generator, which is connected to the AC side of the microgrid, in coordinated action with the dump load. The proposed operational and control strategy does not require the use of batteries and aims to maximize the energy production from wind generation, ensuring the uninterrupted operation of the microgrid. The results have showed that the operational and control strategy allowed the stable operation of the islanded microgrid and that the DC-link voltage control loop added to the diesel generator and the dump load proved to be effective during the typical variations of wind speed and load.

O ambiente de pesquisas virtuais na biblioteca acadêmica: da implantação à consolidação, um longo percurso.

O ambiente da pesquisa acadêmica nas bibliotecas universitárias se apresenta em constante evolução. Nesta perspectiva, as construções de novos espaços se fazem necessários na promoção e acesso à informação, via vários tipos de suportes. Atualmente, antigos paradigmas são sobrepostos com uma velocidade luz. Neste artigo, apresenta-se a implantação, manutenção e consolidação do Setor de Pesquisas Virtuais em uma biblioteca universitária, com vistas à democratização do acesso à informação eletrônica, como também à criação de uma rede de comunicação rápida, eficaz, tendo como foco central as novas Tecnologias da Informação e Comunicação (TICs). Assim, enfoca-se a construção do espaço físico do Setor de Pesquisas Virtuais, através da criação de normas, produtos, serviços e divulgação desse novo recurso. A consolidação deste espaço encontra-se em pleno desenvolvimento, via aquisição de produtos específicos, consorciamentos junto às redes especializadas, geração de novos produtos e, principalmente, a presença direta de um profissional bibliotecário intervindo e mediando o processo da busca e do acesso às informações com segurança e confiabilidade das fontes. Consequentemente, essas ações estão trazendo benefícios à comunidade atendida.

A confiança interorganizacional nas compras

This research is part of the field of organizational studies, focusing on organizational purchase behavior and, specifically, trust interorganizational at the purchases. This topic is current and relevant by addressing the development of good relations between buyer-supplier that increases the exchange of information, increases the length of relationship, reduces the hierarchical controls and improves performance. Furthermore, although there is a vast literature on trust, the scientific work that deal specifically at the trust interorganizational still need further research to synthesize and validate the variables that generate this phenomenon. In this sense, this investigation is to explain the antecedents of trust interorganizational by the relationship between the variable operational performance, organizational characteristics, shared values and interpersonal relationships on purchases by manufacturing industries, in order to develop a robust literature, most consensual, that includes the current sociological and economic, considering the effect of interpersonal relationships in this phenomenon. This proposal is configured in a new vision of the antecedents of interorganizational trust, described as significant quantitative from models Morgan and Hunt (1994), Doney and Cannon (1997), Zhao and Cavusgil (2006) and Nyaga, Whipple, Lynch (2011), as well as qualitative analysis of Tacconi et al. (2011). With regard to methodological aspects, the study assumes the form of a descriptive, survey type, and causal trace theoretical and empirical. As for his nature, the investigation, explicative character, has developed a quantitative approach with the use of exploratory factor analysis and structural equation modeling SEM, with the use of IBM software SPSS Amos 18.0, using the method of maximum verisimilitude, and supported by technical bootstraping. The unit of analysis was the buyer-supplier relationship, in which the object under investigation was the supplier organization in view of the purchasing company. 237 valid questionnaires were collected among key informants, using a simple random sampling developed in manufacturing industries (SIC 10-33), located in the city of Natal and in the region of Natal. The first results of descriptive analysis demonstrate the phenomenon of interorganizational trust, in which purchasing firms believe, feel secure about the supplier. This demonstration showed high levels of intensity, predominantly among the vendors that supply the company with materials that are used directly in the production process. The exploratory and confirmatory factor analysis, performed on each variable alone, generated a set of observable and unobservable variables more consistent, giving rise to a model, that needed to be further specified. This again specify model consists of trajectories was positive, with a good fit, with a composite reliability and variance extracted satisfactory, and demonstrates convergent and discriminant validity, in which the factor loadings are significant and strong explanatory power. Given the findings that reinforce the model again specify data, suggesting a high probability that this model may be more suited for the study population, the results support the explanation that interorganizational trust depends on purchases directly from interpersonal relationships, sharing value and operating performance and indirectly of personal relationships, social networks, organizational characteristics, physical and relational aspect of performance. It is concluded that this trust can be explained by a set of interactions between these three determinants, where the focus is on interpersonal relationships, with the largest path coefficient for the factor under study

Uma abordagem dirigida a modelo para a geração de casos de teste baseada na detecção de cenários implícitos

Dissertação (mestrado)—Universidade de Brasília, Instituto de Ciências Exatas, Departamento de Ciência da Computação, 2015.

Controle de sistema não linear de separação gás/líquido sob ação de efeitos transientes fluídicos por sliding control

Dissertação (mestrado)—Universidade de Brasília, Faculdade de Tecnologia, Departamento de Engenharia Mecânica, 2015.

Analisando os discursos dos Deputados Federais : a Linguística da informação contábil nos discursos sobre Contabilidade Pública

Analisa a linguística das informações contábeis nos discursos Parlamentares feitos no Plenário da Câmara dos Deputados. Como metodologia, optou-se por realizar uma pesquisa documental sobre os discursos pronunciados em plenário pelos Deputados no período de 2010 a 2014 e analisá-los pelo método de análise de conteúdo de Bardin. Como resultado, verificou-se que a maioria dos deputados prefere analisar a confiabilidade da informação contábil pela dimensão semântica da semiótica contábil.

A satisfação profissional e a cultura organizacional : uma análise a partir do modelo ASH no Centro Federal de Educação Tecnológica do Rio Grande do Norte

With the need of the companies in becoming more competitive within the market, it arises an incessant search for selective human potential, with a high level of capacity and low rotativity, which motivation results in production raise, quality optimization and waste reduction. This scenario requires a strategy development which advantages the Human Resources Quality Management. This way, the model of the Human System Audit (HSA), developed by the Spanish researchers Ouijano and Navarro, presents itself as an important tool to diagnosis and evaluation, contemplating the environment where the organization is inserted, its strategies, its organizational design, its processes and its organizational effectiveness. In this sense, the present study has identified the existent relation between the professional satisfaction and the Organizational Culture, based in the model HSA. The research has been a quantitative-descriptive one and has had as population the technical-administrative workers from the Federal Center of Technical Education of Rio Grande do Norte (CEFET RN). The data collection has occurred during May, 2008, by means of the application of a questionnaire in the HSA model. The sample was composed by 167 subjects, distributed among the Five units of the institution. It was used the factorial analysis, with the extraction method of main components and orthogonal rotation varimax, in order to extract the dimensions of the satisfaction and of the organizational culture and the calculation of Cronbach s Alpha coefficient, to evaluate the reliability of these dimensions. The factorial analysis of the satisfaction indicators has identified four factors,, all of them showing significance: gratefulness and relationship , self-realization , stability and security and physical conditions and social benefits . The result of the factorial analysis with the indicators of the organizational culture has extracted four factors and among them, three of them have obtained significance: Personal Satisfaction Style , Competitive-Denial-Power Style and the Conventional-Dependent Style . After identifying the dimensions of the satisfaction and culture found at CEFET-RN, it has been notice the existence or not of relation among them, through the application of Pearson s coefficient. It has been verified that all of the dimensions of the Professional satisfaction are correlated with some dimension of the organizational culture, having in outstand position, with higher intensity, the relation between the culture style of Personal Satisfaction and the satisfaction factor referring to the self-realization

A gestão da informação sob a luz do Enterprise Content Management (ECM): um estudo de caso em uma universidade pública

This work involves the organization and content perspectives on Enterprise Content Management (ECM) framework. The case study at the Federal University of Rio Grande do Norte was based on ECM model to analyse the information management provided by the three main administrative systems: The Integrated Management of Academic Activities (SIGAA), Integrated System of Inheritance, and Contracts Administration (SIPAC) and the Integrated System for Administration and Human Resources (SIGRH). A case study protocol was designed to provide greater reliability to research process. Four propositions were examined in order to reach the specific objectives of identification and evaluation of ECM components from UFRN perspective. The preliminary phase provided the guidelines for the data collection. In total, 75 individuals were interviewed. Interviews with four managers directly involved on systems design were recorded (average duration of 90 minutes). The 70 remaining individuals were approached in random way in UFRN s units, including teachers, administrative-technical employees and students. The results showed the presence of many ECM elements in the management of UFRN administrative information. The technological component with higher presence was "management of web content / collaboration". But initiatives of other components (e.g. email and document management) were found and are in continuous improvement. The assessment made use of eQual 4.0 to examine the effectiveness of applications under three factors: usability, quality of information and offered service. In general, the quality offered by the systems was very good and walk side by side with the obtained benefits of ECM strategy adoption in the context of the whole institution

Qualidade dos empregos e a carcinicultura marinha nos laboratórios da praia de Barreta/RN

To present research had for objective to study the quality of the employment in the maturation Laboratories and larviculture of the Beach of Barreta/RN, adopting for so much the criteria used by Reinecke(1999) to characterize a quality employment: surrender, benefits non salary, regularity and work reliability and of the wage, contractual status, social protection, work day, intensity of the work, risk of accidents and of occupational diseases, involvement in linked decisions to the section work, possibility for the development of professional qualifications. Of the exam of the data it was verified that the generated employments are considered employments of good quality. However, this result should be analyzed to the light of a context of extreme informality and of precarization of the work. Therefore, the results should be relativized. He/she/you imports to retain that one of the limitations of the study resides in the impossibility of generalizing the data for the whole section of the sea carcinicultura. In spite of that fact, he/she is considered that the objectives of the research were assisted fully and that the characterization of the profile of the employment generated by the section of the shrimpculture it is extremely important for the drawing of public politics gone back to foment this activity.

Fatores críticos de sucesso como antecedentes da aceitação de um sistema de informação em uma universidade federal

In recent decades the public sector comes under pressure in order to improve its performance. The use of Information Technology (IT) has been a tool increasingly used in reaching that goal. Thus, it has become an important issue in public organizations, particularly in institutions of higher education, determine which factors influence the acceptance and use of technology, impacting on the success of its implementation and the desired organizational results. The Technology Acceptance Model - TAM was used as the basis for this study and is based on the constructs perceived usefulness and perceived ease of use. However, when it comes to integrated management systems due to the complexity of its implementation,organizational factors were added to thus seek further explanation of the acceptance of such systems. Thus, added to the model five TAM constructs related to critical success factors in implementing ERP systems, they are: support of top management, communication, training, cooperation, and technological complexity (BUENO and SALMERON, 2008). Based on the foregoing, launches the following research problem: What factors influence the acceptance and use of SIE / module academic at the Federal University of Para, from the users' perception of teachers and technicians? The purpose of this study was to identify the influence of organizational factors, and behavioral antecedents of behavioral intention to use the SIE / module academic UFPA in the perspective of teachers and technical users. This is applied research, exploratory and descriptive, quantitative with the implementation of a survey, and data collection occurred through a structured questionnaire applied to a sample of 229 teachers and 30 technical and administrative staff. Data analysis was carried out through descriptive statistics and structural equation modeling with the technique of partial least squares (PLS). Effected primarily to assess the measurement model, which were verified reliability, convergent and discriminant validity for all indicators and constructs. Then the structural model was analyzed using the bootstrap resampling technique like. In assessing statistical significance, all hypotheses were supported. The coefficient of determination (R ²) was high or average in five of the six endogenous variables, so the model explains 47.3% of the variation in behavioral intention. It is noteworthy that among the antecedents of behavioral intention (BI) analyzed in this study, perceived usefulness is the variable that has a greater effect on behavioral intention, followed by ease of use (PEU) and attitude (AT). Among the organizational aspects (critical success factors) studied technological complexity (TC) and training (ERT) were those with greatest effect on behavioral intention to use, although these effects were lower than those produced by behavioral factors (originating from TAM). It is pointed out further that the support of senior management (TMS) showed, among all variables, the least effect on the intention to use (BI) and was followed by communications (COM) and cooperation (CO), which exert a low effect on behavioral intention (BI). Therefore, as other studies on the TAM constructs were adequate for the present research. Thus, the study contributed towards proving evidence that the Technology Acceptance Model can be applied to predict the acceptance of integrated management systems, even in public. Keywords: Technology

Autoeficácia, características sociodemográficas e capacitação profissional: um estudo com servidores de uma Universidade Federal

Self-efficacy, the construct developed by Albert Bandura in 1977 and widely studied around the world, means the individual's belief in his own capacity to successfully perform a certain activity. This study aims to determine the degree of association between sociodemographic characteristics and professional training to the levels of Self-Efficacy at Work (SEW) of the Administrative Assistants in a federal university. This is a descriptive research submitted to and approved by the Ethics Committee of UFRN. The method of data analysis, in quantitative nature, was accomplished with the aid of the statistical programs R and Minitab. The instrument used in research was a sociodemographic data questionnaire, variables of professional training and the General Perception of Self-efficacy Scale (GPSES), applied to the sample by 289 Assistants in Administration. Statistical techniques for data analysis were descriptive statistics, cluster analysis, reliability test (Cronbach's alpha), and test of significance (Pearson). Results show a sociodemographic profile of Assistants in Administration of UFRN with well-distributed characteristics, with 48.4% men and 51.6% female; 59.9% of them were aged over 40 years, married (49.3%), color or race white (58%) and Catholics (67.8%); families are composed of up to four people (75.8%) with children (59.4%) of all age groups; the occupation of the mothers of these professionals is mostly housewives (51.6%) with high school education up to parents (72%) and mothers (75.8%). Assistants in Administration have high levels of professional training, most of them composed two groups of servers: the former, recently hired public servants (30.7%) and another with long service (59%), the majority enter young in career and it stays until retirement, 72.4% of these professionals have training above the minimum requirement for the job. The analysis of SEW levels shows medium to high levels for 72% of assistants in administration; low SEWclassified people have shown a high average of 2.7, considered close to the overall mean presented in other studies, which is 2.9. The cluster analysis has allowed us to say that the characteristics of the three groups (Low, Medium and High SEW) are similar and can be found in the three levels of SEW representatives with all the characteristics investigated. The results indicate no association between the sociodemographic variables and professional training to the levels of self-efficacy at work of Assistants in Administration of UFRN, except for the variable color or race. However, due to the small number of people who declared themselves in color or black race (4% of the sample), this result can be interpreted as mere coincidence or the black people addressed in this study have provided a sense of efficacy higher than white and brown ones. The study has corroborated other studies and highlighted the subjectivity of the self-efficacy construct. They are needed more researches, especially with public servants for the continuity and expansion of studies on the subject, making it possible to compare and confirm the results

Síndrome de Burnout : um estudo com guias de turismo regional em Natal-RN

Burnout is a psychological syndrome triggered in response to continuous exposure to interpersonal stressors. It is considered a multifactorial construct, which is commonly characterized by three dimensions: emotional exhaustion, dehumanization, and lack of personal accomplishment.This study aimed to verify if the three characteristics of burnout (exhaustion, lack of dehumanization and personal accomplishment) are present in people working as guides Tourism in Natal - RN. It is a descriptive and quantitative study. 109 subjects were surveyed. Data collection was done through the use of questionnaires, the instrument used was the characterization of the Burnout Scale (ECB) created and validated in Brazil by Trocoli and Tamayo (2000). In order to analyze data we used descriptive statistics, analysis of core measures, exploratory and confirmatory factor analysis, reliability analysis, cluster analysis, multiple discriminant and Spearman correlation. Factor analysis identified four factors that explain 58.3% of the total variance. Those factors were named exhaustion, deception, avoidance, and dehumanization. The reliability of the instrument, as measured by Cronbach's Alpha was 0.918, which is considered excellent reliability. The 109 subjects were grouped into three cluster, which had the deception, avoidance, and dehumanization as discriminant. It is possible to conclude that the characteristics of burnout syndrome are present in the studied population where 19 people are on the high level of burnout, moderate in 32 and 56 in the light. The correlations between socio-demographic variables studied and the dimensions of burnout, were few and weak. The variable leave for health reasons in the study appeared to be related to feelings of exhaustion and avoidance behavior appeared related to younger individuals and who work only in the activity of Receptive Tourism Guide. Verification of the incidence of burnout in individuals surveyed suggest the need to adopt intervention strategies are individual, organizational and / or combined

Processo de formulação estratégica sob a perspectiva dos decisores da CAERN

Os estudos sobre estratégia têm se difundido há muitos anos e seu processo de formulação também está inserido no cotidiano dos gestores. O objetivo do presente trabalho é constatar se há relação entre o pensamento, formulação e mudança estratégica e o nível acadêmico, hierárquico e tempo no cargo dos decisores da CAERN. A abordagem teórica é realizada com os seguintes pontos: estratégia, Decisão e liderança organizacional e o processo de formação da estratégia (Pensamento estratégico; Formulação da estratégia; Mudança estratégica). O estudo é de caráter exploratório descritivo. Para a tabulação e análise dos dados, utilizou-se um programa estatístico em que foi adotada a técnica de análise fatorial, e verificou-se a confiabilidade da escala de Likert utilizada no questionário através do teste Alfa de Cronbach e análise de Spearman a fim de constatar a correlação das variáveis e proporcionar uma abordagem quantitativa à pesquisa. Todos os respondentes da pesquisa são tomadores de decisão cujos níveis hierárquicos que obtiveram representatividade na amostra foram coordenadores, gerentes e chefes de seção. A partir das análises dos resultados do estudo, constatou-se que, das hipóteses levantadas, apenas uma se mostrou coerente com a realidade dos profissionais responsáveis pela estratégia organizacional da empresa: Há correlação entre a formulação estratégica e o nível acadêmico dos decisores (no constructo de formulação deliberada). Notouse também que o nível de formação acadêmica (nível superior) é importante e influencia diretamente no processo da formulação estratégica. Conclui-se que na organização em estudo o conhecimento dos gestores interfere na formulação estratégica

Catálogo de Serviços de TI

As Tecnologias de Informação são responsáveis pelas transformações que vivemos, pois permitiram a construção de um mundo global, quebraram fronteiras, gerando conhecimento de uma forma cada vez mais rápida o que levanta enormes desafios às organizações. Estas transformações originam a necessidade de as organizações procurarem soluções e inovarem o seu modelo de estratégia organizacional, para conseguirem sobreviver e agregarem valor ao negócio. As Tecnologias de Informação são parte integrante nos processos das empresas, levando à necessidade de estarem alinhados com a estratégia de Governance, procurando aumentar a confiabilidade das suas operações e o presente trabalho aborda a adoção das melhores práticas das frameworks orientadas para esta área nomeadamente o COBIT 5, a ITIL V3, introduzindo os conceitos de Governance de TI e Gestão de TI. A Design Science Research foi a metodologia de investigação adotada, pois permite a construção e operacionalização de artefactos para os SI e encontrar uma solução para a construção de um Catálogo de Serviços como fator diferenciador para o negócio. Para a construção de um Catálogo de Serviços, é proposto um método baseado nas melhores práticas para a área dos Sistemas de informação, em que este passa a ser o principal ponto de contacto, permitindo o registo dos pedidos, mas também a definição de tempos de resposta, custos, faturação de serviços e ainda a construção de um repositório de conhecimento. São definidos os processos que se consideram mais relevantes, são propostos artefactos para a construção do catálogo, é efetuada a modelação em BPMN dos processos inerentes ao registo de pedidos, pois desta forma facilita o entendimento, bem como a sua implementação.

Dimensionamento amostral para determinação da condutividade elétrica individual de sementes de girassol.

RESUMO: O teste de condutividade elétrica é um teste de vigor de sementes utilizado para avaliar a qualidade das sementes e complementar o teste de germinação. O tamanho da amostra necessária para a estimação da média de condutividade elétrica de sementes é diretamente proporcional à variabilidade dos dados e confiabilidade desejada na estimativa. Uma técnica adequada para dimensionamento amostral é a utilização de intervalos de confiança, obtidos por reamostragem. Essa técnica tem a vantagem de não depender da distribuição de probabilidade dos dados. Assim, o objetivo deste trabalho foi estimar o tamanho de amostra necessário para o teste de condutividade elétrica individual em sementes de girassol. Foram utilizadas sete lotes de sementes de girassol, sendo três lotes da cultivar Hélio 250 (A, B e C), dois lotes da cultivar BRS 323 (D e E) e dois lotes da cultivar BRS 324 (F e G). O teste de condutividade elétrica individual foi realizado com 400 sementes de cada lote e o tamanho de amostra foi determinado pelo número de sementes a partir do qual a amplitude do intervalo de confiança de 95% (AIC95%) foi menor ou igual a 10, 15 e 20% da estimativa da média. Tempos de embebição de vinte e quatro hora possibilitam utilizar os menores tamanhos de amostras. O tamanho de amostra de 257 sementes é recomendado para a amplitude do intervalo de confiança de 95% igual a 20% da estimativa da média. ABSTRACT: The aim of this study was to estimate the sample size required for the individual electrical conductivity test in sunflower seeds. The sample size of 257 seeds is recommended for the amplitude of the 95% confidence interval of 20% of the mean estimate.