6 resultados para Dynamic systems theory
em Universidade Federal do Rio Grande do Norte(UFRN)
Resumo:
This work has as its main purpose to investigate the contribution of supply chain management in order to obtain competitive advantage by companies from the textile industry and from Ceará footwear industry, focusing its analysis mainly in the interorganizational relations (dyadic). For this, the theoretical referential contemplates different explanatory streams of the competitive advantage, detaching the relational perception of the resources theory, as well as, the main presuppositions of the supply chain management which culminates with the development of an analysis sample that runs the empirical study; the one which considers an expanded purpose of the supply chain which includes the government and the abetment institutions as institutional environment representatives. Besides supply chain management consideration as a competitive advantage source, the work also tried to identify other possible competitive advantage sources for the companies of the investigated sectors. It represents a study of multiple interpretive cases, having four cases as a total; meaning two cases in each one of the sectors, which used as a primary data collecting instrument a semi-structured interview schedule. Different methods were used for the data analysis, the content analysis and the constant comparison methods, the analytical procedure originated from the grounded theory research strategy, which were applied the Atlas/ti software recourse. Considering the theoretical referential and the used analysis sample, four basic categories of the work were defined, including its respective proprieties and dimensions: (1) characteristics concerning to the relationship with the supplier; (2) the company relations with the government; (3) the company relations with the abetment institutions and; (4) obtaining sources of competitive advantage. In general, the applied research in the footwear sector revealed that in the relationships of the researched companies related to its suppliers, there is a predominance of the partnership system and the main presuppositions of the supply chain management are applied which contributes for the acquisition of the relational competitive advantage; while in the textile sector, only some of these presuppositions are applied, with little contribution for the relational competitive advantage. The main resource which was accessed by the companies in both sectors through its relationships with the government and the abetment institutions are the tax incentives which, for the footwear companies, contribute for the acquisition of the temporary competitive advantage in relation to the contestants who do not own productive installations in the Northeast region, it also conducts to a competitive parity situation in relation to the contestants who own productive installations in the Northeast region and to the external market contestants; while for the companies of the textile sector, the tax incentives run the companies to a competitive parity situation in relation to its contestants. Furthermore, the investigated companies from the two sectors possess acquisition sources of the competitive advantage which collimate with different explanatory streams (industrial analysis, resources theory, Austrian school and the dynamic capabilities theory), although there is a predominance of the product innovation as a competitive advantage source in both sectors, due to the bond of these with the fashion tendencies
Resumo:
The importance of the airport sector in the development of a country refers to the need for studies on management of airports, to aid the process of decision making. In Brazil, growth in passenger demand is why investments in order to balance the capacity of an airport with air demand. Thus, the study aims to develop a model for Dynamic Systems able to assist airport management in Brazilian sizing subsystems an airport (Passenger Terminal, Runway and Patio). The methodology of this work consists in the steps of defining the problem, formulating the hypothesis dynamic building simulation model, and validation experiments. Finally, we examined the status of each subsystem in thirteen Brazilian airports in scenarios current, most likely and optimistic for air passenger demand
Resumo:
The industries are getting more and more rigorous, when security is in question, no matter is to avoid financial damages due to accidents and low productivity, or when it s related to the environment protection. It was thinking about great world accidents around the world involving aircrafts and industrial process (nuclear, petrochemical and so on) that we decided to invest in systems that could detect fault and diagnosis (FDD) them. The FDD systems can avoid eventual fault helping man on the maintenance and exchange of defective equipments. Nowadays, the issues that involve detection, isolation, diagnose and the controlling of tolerance fault are gathering strength in the academic and industrial environment. It is based on this fact, in this work, we discuss the importance of techniques that can assist in the development of systems for Fault Detection and Diagnosis (FDD) and propose a hybrid method for FDD in dynamic systems. We present a brief history to contextualize the techniques used in working environments. The detection of fault in the proposed system is based on state observers in conjunction with other statistical techniques. The principal idea is to use the observer himself, in addition to serving as an analytical redundancy, in allowing the creation of a residue. This residue is used in FDD. A signature database assists in the identification of system faults, which based on the signatures derived from trend analysis of the residue signal and its difference, performs the classification of the faults based purely on a decision tree. This FDD system is tested and validated in two plants: a simulated plant with coupled tanks and didactic plant with industrial instrumentation. All collected results of those tests will be discussed
Resumo:
The control, automation and optimization areas help to improve the processes used by industry. They contribute to a fast production line, improving the products quality and reducing the manufacturing costs. Didatic plants are good tools for research in these areas, providing a direct contact with some industrial equipaments. Given these capabilities, the main goal of this work is to model and control a didactic plant, which is a level and flow process control system with an industrial instrumentation. With a model it is possible to build a simulator for the plant that allows studies about its behaviour, without any of the real processes operational costs, like experiments with controllers. They can be tested several times before its application in a real process. Among the several types of controllers, it was used adaptive controllers, mainly the Direct Self-Tuning Regulators (DSTR) with Integral Action and the Gain Scheduling (GS). The DSTR was based on Pole-Placement design and use the Recursive Least Square to calculate the controller parameters. The characteristics of an adaptive system was very worth to guarantee a good performance when the controller was applied to the plant
Resumo:
The detection and diagnosis of faults, ie., find out how , where and why failures occur is an important area of study since man came to be replaced by machines. However, no technique studied to date can solve definitively the problem. Differences in dynamic systems, whether linear, nonlinear, variant or invariant in time, with physical or analytical redundancy, hamper research in order to obtain a unique solution . In this paper, a technique for fault detection and diagnosis (FDD) will be presented in dynamic systems using state observers in conjunction with other tools in order to create a hybrid FDD. A modified state observer is used to create a residue that allows also the detection and diagnosis of faults. A bank of faults signatures will be created using statistical tools and finally an approach using mean squared error ( MSE ) will assist in the study of the behavior of fault diagnosis even in the presence of noise . This methodology is then applied to an educational plant with coupled tanks and other with industrial instrumentation to validate the system.
Resumo:
This work has as its main purpose to investigate the contribution of supply chain management in order to obtain competitive advantage by companies from the textile industry and from Ceará footwear industry, focusing its analysis mainly in the interorganizational relations (dyadic). For this, the theoretical referential contemplates different explanatory streams of the competitive advantage, detaching the relational perception of the resources theory, as well as, the main presuppositions of the supply chain management which culminates with the development of an analysis sample that runs the empirical study; the one which considers an expanded purpose of the supply chain which includes the government and the abetment institutions as institutional environment representatives. Besides supply chain management consideration as a competitive advantage source, the work also tried to identify other possible competitive advantage sources for the companies of the investigated sectors. It represents a study of multiple interpretive cases, having four cases as a total; meaning two cases in each one of the sectors, which used as a primary data collecting instrument a semi-structured interview schedule. Different methods were used for the data analysis, the content analysis and the constant comparison methods, the analytical procedure originated from the grounded theory research strategy, which were applied the Atlas/ti software recourse. Considering the theoretical referential and the used analysis sample, four basic categories of the work were defined, including its respective proprieties and dimensions: (1) characteristics concerning to the relationship with the supplier; (2) the company relations with the government; (3) the company relations with the abetment institutions and; (4) obtaining sources of competitive advantage. In general, the applied research in the footwear sector revealed that in the relationships of the researched companies related to its suppliers, there is a predominance of the partnership system and the main presuppositions of the supply chain management are applied which contributes for the acquisition of the relational competitive advantage; while in the textile sector, only some of these presuppositions are applied, with little contribution for the relational competitive advantage. The main resource which was accessed by the companies in both sectors through its relationships with the government and the abetment institutions are the tax incentives which, for the footwear companies, contribute for the acquisition of the temporary competitive advantage in relation to the contestants who do not own productive installations in the Northeast region, it also conducts to a competitive parity situation in relation to the contestants who own productive installations in the Northeast region and to the external market contestants; while for the companies of the textile sector, the tax incentives run the companies to a competitive parity situation in relation to its contestants. Furthermore, the investigated companies from the two sectors possess acquisition sources of the competitive advantage which collimate with different explanatory streams (industrial analysis, resources theory, Austrian school and the dynamic capabilities theory), although there is a predominance of the product innovation as a competitive advantage source in both sectors, due to the bond of these with the fashion tendencies