Gráfico de controle modificado para processos com estruturas complexas de autocorrelação

This work proposes a modified control chart incorporating concepts of time series analysis. Specifically, we considerer Gaussian mixed transition distribution (GMTD) models. The GMTD models are a more general class than the autorregressive (AR) family, in the sense that the autocorrelated processes may present flat stretches, bursts or outliers. In this scenario traditional Shewhart charts are no longer appropriate tools to monitoring such processes. Therefore, Vasilopoulos and Stamboulis (1978) proposed a modified version of those charts, considering proper control limits based on autocorrelated processes. In order to evaluate the efficiency of the proposed technique a comparison with a traditional Shewhart chart (which ignores the autocorrelation structure of the process), a AR(1) Shewhart control chart and a GMTD Shewhart control chart was made. An analytical expression for the process variance, as well as control limits were developed for a particular GMTD model. The ARL was used as a criteria to measure the efficiency of control charts. The comparison was made based on a series generated according to a GMTD model. The results point to the direction that the modified Shewhart GMTD charts have a better performance than the AR(1) Shewhart and the traditional Shewhart.

Estudo da variação da periodicidade e do acoplamento entre superfícies seletivas de frequência com elementos fractais e helicoidais em estruturas de multicamadas

This work aims to investigate the behavior of fractal and helical elements structures in planar microstrip. In particular, the frequency selective surfaces (FSSs) had changed its conventional elements to fractal and helical formats. The dielectric substrate used was fiberglass (FR-4) and has a thickness of 1.5 mm, a relative permittivity 4.4 and tangent loss equal to 0.02. For FSSs, was adopting the Dürer’s fractal geometry and helical geometry. To make the measurements, we used two antennas horns in direct line of sight, connected by coaxial cable to the vector network analyzer. Some prototypes were select for built and measured. From preliminary results, it was aimed to find practical applications for structures from the cascading between them. For FSSs with Dürer’s fractal elements was observed behavior provided by the multiband fractal geometry, while the bandwidth has become narrow as the level of iteration fractal increased, making it a more selective frequency with a higher quality factor. A parametric analysis allowed the analysis of the variation of the air layer between them. The cascading between fractal elements structure were considered, presented a tri-band behavior for certain values of the layer of air between them, and find applications in the licensed 2.5GHz band (2.3-2.7) and 3.5GHz band (3.3-3.8). For FSSs with helical elements, six structures were considered, namely H0, H1, H2, H3, H4 and H5. The electromagnetic behavior of them was analyzed separately and cascaded. From preliminary results obtained from the separate analysis of structures, including the cascade, the higher the bandwidth, in that the thickness of the air layer increases. In order to find practical applications for helical structures cascaded, the helical elements structure has been cascaded find applications in the X-band (8.0-12.0) and unlicensed band (5.25-5.85). For numerical and experimental characterization of the structures discussed was used, respectively, the commercial software Ansoft Designer and a vector network analyzer, Agilent N5230A model.

Serviço de nuvem pública e sua relação com os arranjos de governança de TI e o alinhamento estratégico

Increasingly, the Information Technology (IT) has been used to sustain the business strategies, causing increased its relevance. Therefore IT governance is seen as one of the priorities of organizations at the time. The search for strategic alignment between business and IT is debated as a factor for business success, but even with that importance, usually the main business managers are reluctant to take responsibility for decisions involving IT, mainly due to the complexity of your infrastructure. Since cloud computing is being seen as an element capable of assisting in the implementation of organizational strategies, because their characteristics enable greater efficiency and agility in IT, and is considered as a new computing paradigm. The main objective of the analyze the relationship between IT governance arrangements and strategic alignment with the infrastructure as a service (IaaS) of public cloud computing. Therefore, an exploratory, descriptive and inferential was developed, with approach to the problem of quantitatively research, with descriptive survey method and cross section. An electronic questionnaire that was applied to the ISACA chapters Associates of São Paulo and the Distrito Federal, totaling 164 respondents was used. The instrument used based on the theories of Weill and Ross (2006) for array of IT governance arrangement; Henderson and Venkatraman (1993) and Luftman (2000), for maturity of the strategic alignment model; and NIST (2011 b), ITGI (2007) and CSA (2010) for infrastructure maturity as a service (IaaS) public in its essential characteristics. As regards the main results, this research proved that with public IaaS decision-making structures have changed, with a greater participation of senior executives in all five key IT decisions (IT governance arrangement array) including more technical decisions as architecture and IT infrastructure. With increased participation of senior executives the decrease was also observed in the share of IT specialists, characterizing the decision process with the duopoly archetype (shared decision). With regard to strategic alignment, it was observed that it changes with cloud computing, and organizations with public IaaS, a maturity of strategic alignment with statistically significant and greater difference when compared to organizations without IaaS. The maturity of public IaaS is at the intermediate level (level 3 - "defined process"), with the elasticity and measurement achieved level 4 - "managed and measurable" It was also possible to infer in organizations with public IaaS, there are positive correlations between the key decisions and the maturity of IaaS, especially at the beginning, architecture and infrastructure, and the archetypes involving senior executives and IT specialists. In the correlation between the maturity and mature strategic alignment of public IaaS therefore the higher the strategic alignment, the greater the maturity of the public IaaS and vice versa.

Bi anisotropia em antenas de microfita retangular e estruturas circulares modificadas

The microstrip antennas in your simplest form consist of a ground plane and a dielectric substrate which supports a conductive tape. As these antennas have some limitations, this work presents a study of anisotropic substrates, as well as some results in microstrip antennas with circular patch, aiming to overcome these limitations, especially in applications at 4G technology. These anisotropic substrates are those in which electrical permittivity and magnetic permeability are represented by tensors of second order. The study consists of a theoretical analysis of substrates and development of a mathematical formalism, the Transverse Transmission Line Method, aimed the application of these substrates in microstrip antennas. Among the substrates used in this study, there are the ferrimagnetic and metamaterials, in which some miniaturizations of the antennas are achieved. For antennas with circular patch, are considered arrays and modified ground planes in order to achieve improvement in parameters, in particular, gain and bandwidth. Several simulations have been made and antennas were constructed so that the measured values could be compared with the simulated values.

Materiais a base de estruturas carbonáceas para a remoção de ácidos húmicos em soluções aquosas através da adsorção e oxidação

O presente estudo aborda a utilização de carvão ativado comercial na remoção de ácidos húmicos em meio aquoso. O objetivo principal é desenvolver e caracterizar materiais carbonáceos visando aplicações de remoção de ácidos húmicos em meio aquoso por processos de adsorção e oxidação. Testes de remoção do poluente foram desenvolvidos com a utilização do carvão comercial, carvão modificado a partir de tratamentos ácidos e compósito confeccionado com a impregnação de ferro no carvão. Espumas de carbono com dispersões de carvão ativado e óxidos de ferro também foram desenvolvidas buscando aplicações de remoção do poluente através de processos eletroquímicos. Os resultados das caracterizações demonstraram ganho de área superficial a partir do tratamento ácido, a presença dispersa de ferro em todo carvão na forma de fase maghemita com a introdução do metal, e ganho de estabilidade eletroquímica na espuma, com a presença de dispersões de carvão ativados impregnados com ferro. O processo oxidativo Fenton, foto assistido por radiação UV, demonstrou maior eficiência para remoção do ácido húmico em água.

Utilização do titâneo na confecção de estruturas metálicas em prótese parcial removível

Due to properties such as excellent biocompatibility, high resistance to corrosion and low specific weight, titanium has been considered a material of great interest for Dentistry. It has been widely used in implants and orthognathic surgeries. Recently, titanium has been seen as a feasible alternative for the fabrication of removable partial denture frameworks, either in pure titanium (99.75%) or in titanium alloy forms (Ti-6Al-4V; Ti-6A1-7Nb). Based on a review of the literature, this work studied the use of titanium for the fabrication of removable partial denture frameworks, focusing on its advantages and disadvantages as well as its characteristics. It was concluded that the use of titanium is a convenient option for partially edentulous arches rehabilitation with quite satisfactory and promising clinical results. However, the need for highly-equipped laboratories increases the cost, preventing its large scale use.

Utilização do titâneo na confecção de estruturas metálicas em prótese parcial removível

Due to properties such as excellent biocompatibility, high resistance to corrosion and low specific weight, titanium has been considered a material of great interest for Dentistry. It has been widely used in implants and orthognathic surgeries. Recently, titanium has been seen as a feasible alternative for the fabrication of removable partial denture frameworks, either in pure titanium (99.75%) or in titanium alloy forms (Ti-6Al-4V; Ti-6A1-7Nb). Based on a review of the literature, this work studied the use of titanium for the fabrication of removable partial denture frameworks, focusing on its advantages and disadvantages as well as its characteristics. It was concluded that the use of titanium is a convenient option for partially edentulous arches rehabilitation with quite satisfactory and promising clinical results. However, the need for highly-equipped laboratories increases the cost, preventing its large scale use.

Controle ativo de vibração em estruturas inteligentes utilizando um controlador por modos deslizantes com compensação difusa

Smart structures and systems have the main purpose to mimic living organisms, which are essentially characterized by an autoregulatory behavior. Therefore, this kind of structure has adaptive characteristics with stimulus-response mechanisms. The term adaptive structure has been used to identify structural systems that are capable of changing their geometry or physical properties with the purpose of performing a specific task. In this work, a sliding mode controller with fuzzy inference is applied for active vibration control in an SMA two-bar truss. In order to obtain a simpler controller, a polynomial model is used in the control law, while a more sophisticated version, which presents close agreement with experimental data, is applied to describe the SMA behavior of the structural elements. This system has a rich dynamic response and can easily reach a chaotic behavior even at moderate loads and frequencies. Therefore, this approach has the advantage of not only obtaining a simpler control law, but also allows its robustness be evidenced. Numerical simulations are carried out in order to demonstrate the control system performance.

Controle ativo de vibração em estruturas inteligentes utilizando um controlador por modos deslizantes com compensação difusa

Smart structures and systems have the main purpose to mimic living organisms, which are essentially characterized by an autoregulatory behavior. Therefore, this kind of structure has adaptive characteristics with stimulus-response mechanisms. The term adaptive structure has been used to identify structural systems that are capable of changing their geometry or physical properties with the purpose of performing a specific task. In this work, a sliding mode controller with fuzzy inference is applied for active vibration control in an SMA two-bar truss. In order to obtain a simpler controller, a polynomial model is used in the control law, while a more sophisticated version, which presents close agreement with experimental data, is applied to describe the SMA behavior of the structural elements. This system has a rich dynamic response and can easily reach a chaotic behavior even at moderate loads and frequencies. Therefore, this approach has the advantage of not only obtaining a simpler control law, but also allows its robustness be evidenced. Numerical simulations are carried out in order to demonstrate the control system performance.

Análise da eficiência de contratos de serviços de elevada especificidade terceirizados pela petrobras

The definition of the boundaries of the firms is subject that has occupied the organizational theorists long ago, being the seminal work of Coase (1937) indicated as the trigger for one theoretical evolution, with emphasis on governance structures, which led to a modern theory of incomplete contracts. The Transaction Cost Economics (TCE) and Agency Theory arise within this evolution, being widely used in studies related to the theme. Empirically, data envelopment analysis (DEA) has established itself as a suitable tool for analysis of efficiency. Although TCE argues that specific assets must be internalized, recent studies outside the mainstream of theory show that, often, firms may decide, for various reasons, hire them on the market. Researches on transaction costs face with the unavailability of information and methodological difficulties in measuring their critical variables. There`s still the need for further methodological deepening. The theoretical framework includes classic works of TCE and Agency Theory, but also more recent works, outside the mainstream of TCE, which warn about the existence of strategies in use of specific assets that aren`t necessarily aligned with the classical ideas of TCE. The Brazilian oil industry is the focus of this thesis, that aimed to evaluate the efficiency of contracts involving high specificity service outsourced by Petrobras. In order to this, we made the categorization of outsourced services in terms of specificity, as well the description of services with higher specificity. Then, we verified the existence of relationship between the specificity of services and a number of variables, being found divergent results than those that are preached by the mainstream of TCE. Then, we designed a DEA model to analyze the efficiency in the use of onshore drilling rigs, identified among the services of highest specificity. The next step was the application of the model to evaluate the performance of drilling rigs contracts. Finally, we verified the existence of relationship between the efficiency of contracts and a number of variables, being found, again, results not consistent with the theory mainstream. Regarding to analyze of efficiency of drilling rigs contracts, the model developed is compatible with what is found in academic productions in efficiency of drilling rigs. The results on efficiency show a wide range of scores, with efficiencies ranging from 31.79% to 100%, being low the sample efficiency average. There is consonance between the model results and the practices adopted by Petrobras. The results strengthen the DEA as an important tool in studies of efficiency with possibility to use for analysis other types of contracts. In terms of theoretical findings, the results reinforce the arguments that there are situations in which the strategies of the organizations, in terms of use of assets and services of high specificity, do not necessarily follow what is recommended by the mainstream of TCE

Construção das capacidades organizacionais de tecnologia da informação no contexto dos sistemas institucionais integrados de gestão da UFRN

The IT capability is a organizational ability to perform activities of this role more effectively and an important mechanism in creating value. Its building process (stages of creation and development) occurs through management initiatives for improvement in the performance of their activities, using human resources and IT assets complementary responsible for the evolution of their organizational routines. This research deals with the IT capabilities related to SIG (integrated institutional management systems), built and deployed in UFRN (Universidade Federal do Rio Grande do Norte) to realization and control of administrative, academic and human resources activities. Since 2009, through cooperative agreements with federal and educational institutions of direct administration, UFRN has supported the implementation of these systems, currently involving more than 30 institutions. The present study aims to understand how IT capabilities, relevant in the design, implementation and dissemination of SIG, were built over time. This is a single case study of qualitative and longitudinal nature, performed by capturing, coding and analysis from secondary data and from semi-structured interviews conducted primarily with members of Superintenência de Informática, organizational unit responsible for SIG systems in UFRN. As a result, the technical, of internal relationship and external cooperation capabilities were identified as relevant in the successful trajectory of SIG systems, which have evolved in different ways. The technical capacity, initiated in 2004, toured the stages of creation and development until it reached the stage of stability in 2013, due to technological limits. Regarding the internal relationship capability, begun in 2006, it toured the stages of creation and development, having extended its scope of activities in 2009, being in development since then. Unlike the standard life cycle observed in the literature, the external cooperation capability was initiated by an intensity of initiatives and developments in the routines in 2009, which were decreasing to cease in 2013 in order to stabilize the technological infrastructure already created for cooperative institutions. It was still identified the start of cooperation in 2009 as an important event selection, responsible for changing or creating trajectories of evolution in all three capacities. The most frequent improvements initiatives were of organizational nature and the internal planning activity has been transformed over the routines of the three capabilities. Important resources and complementary assets have been identified as important for the realization of initiatives, such as human resources technical knowledge to the technical capabilities and external cooperation, and business knowledge, for all of them, as well as IT assets: the iproject application for control of development processes, and the document repository wiki. All these resources and complementary assets grew along the capacities, demonstrating its strategic value to SINFO/UFRN

Recursos intangíveis de um destino turístico: um estudo de desempenho da cidade de Natal tendo como base a teoria das capacidades dinâmicas

O objetivo desta tese foi analisar os recursos intangíveis de um destino turístico. Foi feito um estudo de desempenho da cidade de Natal tendo como base a teoria das capacidades dinâmicas. Inicialmente, foi desenvolvido um instrumento de pesquisa para oportunizar a construção de um modelo de medida com vistas à captação de variáveis latentes para os recursos intangíveis existentes no setor do turismo em Natal-RN. Em seguida, foi realizada uma análise dos recursos intangíveis que são evidenciados pelos turistas acerca da cidade. Finalmente, foi feita a investigação de um modelo de estrutura que estabeleceu as relações entre as variáveis latentes dos recursos intangíveis e a percepção de desempenho do turismo na cidade de Natal. Procedeu-se uma revisão de literatura para construção de um modelo inicial acerca dos ativos intangíveis dentro da teoria das capacidades e foram relacionados dez recursos, quais sejam: recursos humanos prestadores de serviços; recursos humanos como gestores; cultura local; conservação do meio ambiente; know-how empresarial; inovação empresarial; tecnologia; marca; preço; e promoção. Estes dez recursos, em conjunto, seriam responsáveis pelo desempenho do destino turístico. Após ser realizada uma análise de equações estruturais, apenas quatro recursos manifestaram relações com o desempenho: marca; cultura; conservação do meio ambiente; e preço. Análisando dos dados, verificou-se que a variável desempenho positivo da cidade na ótica do turista se manifestou fortemente e foi influenciada de forma forte pela cultura local, marca e conservação do meio ambiente em conjunto. O preço foi influenciado pelo desempenho positivo mostrando que o turista sente que o preço pago foi satisfatório diante dos atributos do destino Provavelmente, isso seja um ponto positivo muito forte para o destino turístico de Natal, pois, em termos de recursos intangíveis e de juntos formarem capacidades, eles são inimitáveis, raros e são capazes de se ajustarem às mudanças organizacionais e ambientais, para reconfigurar os ativos e as estruturas de um destino, corroborando, assim, com a teoria das capacidades dinâmicas. Esses recursos da cidade de Natal, como destino turístico, são únicos e provavelmente têm um peso muito maior para o desempenho da cidade do que problemas existentes na localidade. Logo, esses atributos devem ser estimulados a continuar crescendo e se modificando de acordo com as exigências atuais e futuras de consumo

Desempenho internacional de empresas exportadoras: um modelo estrutural baseado em capacidades organizacionais e ambiente

The internationalization as an organizational phenomenon fundamentally strategic had as theoretical contributions some Schools that throughout the decades 60, 70, and 80 developed behavioral and economic approaches in order to explain the process. The behavioral approach deals with the perception of phenomenon as a gradual process from the perspective of the executives behavior (JOHANSON and VAHLNE, 1977; HALLÉN and WIEDERSHEIM - PAUL, 1979; CZINKOTA, 1985). This phenomenon in permanent theoretical and managerial evolution made an opportunity to build this investigation, whose goal is to analyse the impact comes from organizational capabilities and the external environment on the international performance of exporting firms. For both, were used as theoretical basis two types of analysis for the comprehension of international performance: Strategic Management - Industrial Organization and Resource-Based View and International Businesses - Current Economic and Behavioral. It was made a cross-sectional survey-based explanatory research, including 150 exporting companies with operations in the Northeast of Brazil. A conceptual model was made with eight constructs and eight research hypotheses, representative of the effects of external factors on international performance. The data were processed using the Exploratory Factor Analysis and Structural Equation Modeling. The structural equations model was reespecified and estimated through the use of the maximum-likelihood method up to achieve adequated values of indexes of adjustment. As the main theoretical contribution, were identified organizational and physical resources which shows the importance of the management skills development, of the learning capability and capability to establish strategic alliances abroad. That because the knowledge, as the operational point of view as in its strategic application, offers to organization conditions of market positioning which can create opportunities sustainable competitive advantages and which impact the performance of international companies

Relações interorganizacionais e confiança no setor da carcinicultura: um estudo de caso na camanor produtos marinhos

This study investigated how the types of confidence based on competence and good will act in the formation and maintenance of cooperation relationships between the Camanor and its partners (Aquatec, Purina, Caçuá, Uvifrios and Malta / Cleyton). It used organizational approaches on networks based primarily on studies of Powell (1987, 1990), Das and Teng (2000, 2001), Child (2001) and Contractor and Lorange (2004) which have described the advantages that cooperative relationships can provide, as well as their limits as alternative governance structures. Confidence has been considered an important factor affecting the actions and development of organizations involved in networks or in strategic alliances (ZAHEER; HARRIS, 2006) and is the most appropriate control mechanism in these situations (SYDOW, 1998). Confidence is seen from two different approaches: the economic and the sociological (ZAHEER; HARRIS, 2006). To facilitate the understanding of confidence some typologies have been created, as proposed by Barney and Hansen (1994), Lane (1998), Das and Teng (2000), Child (2001) and Wever, Martens and Vandenbempt (2005). This study made use of the case study as proposition of Yin (2005). Semi-structured interviews were held with pre-determined routes, in a single stage performed in early 2008. The research subjects were owners and / or responsible for Camanor and its business partners (Aquatec, Purina, Caçuá, Uvifrios and Malta / Cleyton). Also secondary data were collected in several sites related to the industry and enterprises studied, in addition to data collected by previous studies conducted by CARCINEREDES (2006). The primary data were analyzed using the analysing technique of the content proposed by Bardin (1994). Regarding the secondary data, they were qualitatively analyzed according to documentary analysis technique (BARDIN, 1994). Thus, through the data collected, could be concluded that although there is confidence based on good faith in relationships(UZZI, 1998; OF; TENG, 2001), their presence does not determine the formation and / or maintenance of a partnership, serves only in order to facilitate the relationship, making them more flexible. The confidence based on competence (DAS; TENG, 2001) influenced the formation and maintenance of relations studied. Because whether or not to form a relationship with another organization it is used the perception of the partner acts, namely the reputation (image) as decision basis. And it is through the verification of the performance of the partner activities that will determine the continuation of the partnership

Cultura e clima organizacionais: um estudo multicasos em indústrias de laticínios do estado do Rio Grande do Norte

The objective of this study is to investigate if exist relationship between organizational culture and the organizational climate, having as research s locus three dairy industries in the Rio Grande do Norte State. As such, an exploratory-descriptive and conclusive-causal study, with a sample composed of 211 employees of all firms hierarchical levels was undertaken. By way the data collection, the employees personal characteristics, the predominant organizational culture profile and the predominant organizational climate in the industries researched were identified. In order to analyse the organizational culture, the Competing Value Model (CAMERON; QUINN, 2006), with adaptations by Santos (1998, 2000), was used. In order to analyse the organizational climate, the Organizational Climate Measurement Scale, proposed by Martins (et al., 2004, 2008), with modifications, was used. The data were submitted to quantitative statistical analyses, firstly to the set of firms and afterwards to the firms alone, that permitted arrival to the following conclusions: the cultural profiles was met in a balanced way in the researched organizations, with emphasis to clan culture and market culture profiles; the researched organizations have a good organizational climate, based in the Martins (2008) classification, with emphasis to boss and organization s support and physical comfort , being these factors coherent whit the clan culture profile; the personal variables are correlated with the cultural profiles and with the organizational climate factors, however, each organization show its singular form of relation; and the cultural profiles showed influence on organizational climate factors. Thus, the results permitted to conclude that there are relations between the cultural profiles and the organizational climate factors in the researched organizations