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Copyright of Revista Producao Online is the property of Associacao Brasileira de Engenharia de Producao and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Exacta is the property of Exacta - Engenharia de Producao and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Foco (Interdisciplinary Studies Journal) is the property of Revista Foco and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Desenvolvimento e Meio Ambiente is the property of Universidade Federal do Parana and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Desenvolvimento e Meio Ambiente is the property of Universidade Federal do Parana and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

From flocks of birds to the internet, many of the complex systems that we find in nature or in our daily lives can be modeled as networks. Each element (or node) of a network, in turn, can be a dynamical system, i.e., with its variables evolving over time according to some rule(s). But when connecting dynamical systems in a network, several collective phenomena can manifest. Among these phenomena the complete synchronization (CS) of a network can play an indispensable role in some practical applications, which has led several researchers to investigate, for example, what are the conditions and/or structure of a network that guarantee its synchronization, or how to control a network in order to take it to CS. In this manuscript we will try address these issues by taking Kuramoto model as a starting point, analyzing the stability of its solutions and presenting some results that can help us to understand some dynamic aspects of oscillator networks and to answer the question stated in the title. [ABSTRACT FROM AUTHOR]

Copyright of Plural - Revista de Ciências Sociais is the property of Revista Plural and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Purpose – The paper concludes with showing that in the most optimistic scenario, end-of-life (EOL) batteries will account for 86% of energy storage for wind and 36% for solar PV in 2040. Design/methodology/approach – With the growing demand for electric vehicles (EVs), the stock of discarded batteries will increase dramatically if no action is taken for their reuse or recycling. One potential avenue is to reuse them as energy storage systems (ESS) to mitigate the intermittent generation of renewable energy such as solar PV and wind. In a sense, the reliability for solar PV and wind energy can increase if energy storage systems become economically more attractive, making solar and wind systems more attractive through economies of scale. Findings – The paper concludes with showing that in the most optimistic scenario, EOL batteries will account for 86% of energy storage for wind and 36% for solar PV in 2040. Originality/value – The projection of scenarios can contribute to the information of policies, standards and identification of environmental promotion and promotion related to efficient management for EOL batteries.

Copyright of Revista Direito GV is the property of Fundacao Getulio Vargas and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Exacta is the property of Exacta - Engenharia de Producao and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

There have been cases of discontinuity, interruption of submissions, and long delays in manuscript evaluation in low-budget Brazilian journals in information science, possibly related to the capacity and health condition of their editors. What is the effect of increased workload on editors' stress? In this article, we simulate four scenarios of the stress of those editors using data on the number of submissions, evaluations, and editorial decisions. We use system dynamics to model stocks and flows of articles through the editorial process, describing four scenarios of the stress of journal editors for 72 months, with different submission loads. In two scenarios, with moderate submission loads, editors keep stress and total evaluation time at acceptable levels, increasing productivity under a small overhead, in accordance with the literature. In the two scenarios with the highest submission overload, the number of hours worked per month escalates, as well as the total evaluation time, and the accumulated stress. The exclusive but insufficient state funding for journals does not provide for high-quality editorial work in a timely manner. This threatens editors' health and favors the interruption of submissions, delays, and even the collapse of those journals. [ABSTRACT FROM AUTHOR]

Abstract Populations living in favelas are facing even more vulnerabilities with the sudden escalation of the COVID-19 pandemic, as social distancing is challenging in such settings. Furthermore, these populations typically lack proper sanitation and hygiene conditions, which are requirements to adequately control the outbreak. This paper proposes the use of System Dynamics modeling to support the public policy-making process in order to avert negative effects of the pandemic in the Brazilian favelas based on measures elicited from the social movement named “Favelas Contra o Corona.” The simulation model assessed the effectiveness of strategies and policy bundles encompassing temporary transfer of the favela population, supply of hygiene products, emergency sanitation structures, and expansion of Intensive Care Units. Results indicate that a suitable combination of strategies can bring significant effects to the number of avoidable deaths and the availability of Intensive Care Units for the population.

Isomorphism can be understood as the process that leads one population to resemble another in the same environmental conditions. Isomorphic pressures are felt differently depending on the size of the organization and can disturb the adoption of Energy Management Systems, such as ISO 50001. Given institutional differences, how can government´s coercive pressures impact the spread of ISO 50001 in each size group? To what extent can they influence the overall spread of certification? This article applies the Bass diffusion model to assess the ISO 50001 certification over the 2016-2040 period, using a system dynamics modeling approach. It proposes an extension of the diffusion model related to market stakeholder pressure, based on institutional theory. The results showed that financial and fiscal incentives provided the most significant impact on the overall number of certified industries. Large companies are the most relevant segment for certification without additional policies, while smaller ones benefit significantly from incentive programs. This study reinforces the relevance that stakeholders have in promoting greener standards and initiatives, and offers useful lessons on the dynamics of adopting energy management systems.

Abstract Despite the proliferation as well as great advances in the development of dynamic models applied to project management, research that applies system dynamics principles to program management does not seem to be as fertile. The objective of this paper is to obtain a more accurate vision of how the system dynamics theory is being used in the development of the program management field. The bibliometric-qualitative study confirms there is a robust use of system dynamics tools in the project management area, with a wide range of applications as well as solid results. The study, however, also shows that for programs, despite a noticeable increase regarding the interest in program management by organizations, clearly there is much less research uniting program management and system dynamics. More importantly, some dynamic models are being used to improve the performance of programs, however, few studies take into consideration the specific variables from program management. Thus, we conclude that current research on these two topics can only be viewed as fragmented and in its early stages, offering ample room for improvement.

Copyright of Revista Ciência & Saúde Coletiva is the property of Associacao Brasileira de Pos-Graduacao em Saude Coletiva and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract Urban solid waste management is a complex system due to the many variables that compose it, which makes it difficult for managers to make decisions. Among the decision-making tools is system dynamics. To identify the gaps between the literature and the studies about urban solid waste management by using system dynamics method, a survey of published papers on the subject was made, which were later analyzed using some defined criteria, such as the level of the study, the software used for modeling, the variables included in the model, among others. The research identified that, among the stages of solid waste management, the collection process is still little incorporated in the models, being mentioned in only nine studies analyzed. Besides, the environmental, financial and institutional requirements were not adequately explored in the models. Future research should endeavor to include these elements in the models, which will allow the proposed system to be approximated to the complex reality of solid waste management.

Copyright of Direito e Práxis is the property of Editora da Universidade do Estado do Rio de Janeiro (EdUERJ) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this work we present a low-cost activity that aims to investigate the drag force, which acts on the geometry of a disc, through the damped oscillations of a mass-spring system. Using cardboard disks of different radii and controlling the mass of the oscillatory system, keeping it fixed, we studied the influence of the exclusive variation of the magnitude of the drag force on the dynamics of this system, by varying the radius of the disk, keeping all the others fixed system accessible parameters. The video analysis technique is used to track the movement of the system, leading the student to investigate and draw conclusions about the functional dependence of the viscous frictional force with the radius of the disk, as well as to obtain the spring elastic constant and an estimate for the thickness of the disks. [ABSTRACT FROM AUTHOR]

It has been of great interest, both on the part of researchers and investors, to define negotiation rules that make it possible to capture the dynamics of the financial markets. This article presents a negotiation model among financial agents, based on the stock buying and selling process, that form a financial market. For the adaptation of economic agents to the market, a Particle Swarm Optimization (PSO) algorithm was implemented to optimize trading rules between agents aiming at maximizing gains in the market. Times series of artificial markets and real Bovespa brazillian market, descripted by the index Bovespa, were used in the computational simulations. Through the simulations, the dynamics of the interaction of buying and selling between financial agents was explored. The results show that there is a dependence on the gains of the agents in the markets in relation to the trading strategies adopted. On the other hand, in the low markets this dependence was not observed, since no statistically significant differences were found for the amount of wealth accumulated among the market participants. For the Bovespa market, from the sell and purchase thresholds of the trades carried out, the agents that have the best strategies in the negotiations were identified. [ABSTRACT FROM AUTHOR]

Se reconoce que el ambiente térmico es uno de los factores ecológicos más importantes para determinar el crecimiento, el desarrollo y la productividad de animales domésticos con efectos directos e indirectos sobre su fisiología y comportamiento. A pesar de tener una adaptación específica e individual, es muy común que, dentro de las variaciones de temperatura estacionales o diurnas, los animales se enfrenten a situaciones fuera de su zona de confort térmico. Debido al estrés calórico, las vacas lecheras reducen su producción y fertilidad, y por lo tanto, llevan a cabo un aumento en la incidencia de trastornos metabólicos, causando bajos causando bajos ingresos para la finca en corto y mediano plazo. El cambio climático es quizás uno de los factores más importantes en las respuestas de los animales. Este estudio tuvo como objetivo describir y comprender las interacciones de las variables asociadas con el estrés por calor en el ganado lechero. El enfoque del sistema aplicado a este mecanismo fisiológico específico ayuda aliviar el estrés calórico en vacas lecheras cuando se relacionan los aspectos de pastoreo y las necesidades del animal. Se usó una anotación de diagrama de bucle causal para conectar las variables biológicas incluidas en los límites del sistema. Las conexiones causales se validaron con algunas citas bibliográficas sobre la influencia del estrés calórico. Las interconexiones de retroalimentación más importantes resaltadas, subrayan la estructura dominante y los patrones esperados. Se encontraron cuatro bucles balance implicados en los mecanismos fisiológicos utilizados por los animales para reducir la producción de calor metabólico y para regular la homeostasis de la temperatura interna.

Copyright of Revista Producao Online is the property of Associacao Brasileira de Engenharia de Producao and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Producao Online is the property of Associacao Brasileira de Engenharia de Producao and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The clinics, hospitals and health care centers are daily in need to optimize the professional, pharmaceutical, hospital or endowment-infrastructure resources. However, due to multiple random and complex factors, this is a demanding endeavor as they do not have the methodologies that may help the health manager in the process. Because of this, the aim is to develop a systemic methodology and a planning model to define the bed sizes. It is intended to improve the planning and administration of any health care center. To begin, this work studied the key factors affecting the planning, relationships and components in the definition of the number of beds. These inputs were used to set out a causal model and a simulation model under a system dynamics approach integrating these factors. Finally, the simulation results indicate that the need of additional beds is about 9% or 16 beds on average. The results from this work should encourage the managers to develop a clear and holistic idea on this issue and, therefore, to better plan the health care resources. [ABSTRACT FROM AUTHOR]

This paper aimed to analyze the process of information dissemination in socioecological systems. System Dynamics, Agent-Based Modeling, and Social Network Analysis approaches were used for the construction of a hybrid simulation model. An analysis of the characteristics and structural aspects of social networks of the Gorutuba Irrigation Perimeter, in Minas Gerais, was performed. We observed that the most central agents are in key positions for the fl ow of information or on compulsory routes for their spread, thus allowing them to fi lter, retain, or even distort the knowledge. We conclude that policies to improve the fl ow of information to increase resilience should be based on targeting leading agents. [ABSTRACT FROM AUTHOR]

System dynamics is an approach to analyze the behavior of complex systems, such as the productive chains, strictly considering the inherent characteristics. This approach is based on mathematical concepts of nonlinear processes developed in mathematics and physics and consolidated in engineering. The concepts inherent in this approach assists in creating a mathematical model that represents a production chain by using computer simulation. Thus, the main objective of this paper is to present the formalization of the dynamic model of assessing the sustainability of Brazilian ethanol production. We analyzed the external environment and the scenarios needed for a deeper understanding of relation of cause and effect, causal loops and diagrams of flows and stocks because of the awareness stage, with regard to understanding the problems involved, according to methodology known as design science.

The analysis of public policies often fails to account for effects beyond mere cost-benefit analysis. Incorporating elements from the literature on system dynamics, complexity and legitimacy, the present paper develops a framework to understand long-term effects and important constraints for public policies. We call it the thresholds framework, considering the existence of different thresholds in the life of a policy. The framework relies on the application of conceptual lenses to understand essential aspects of the social reality. Using the proposed conceptual repertoire, the paper applies the framework to a specific policy, the Brazilian Worker Food Program (WFP), which currently benefits around 20 million employees working for 250,000 companies in Brazil. The thresholds framework incorporates legitimacy and complexity issues and it is sufficiently flexible for the pursuit of different strategies of inquiry. It may be used to guide the design of business programs in dynamic contexts, such as the ones found in modern social cause environments.

Objective: The present study analyzes how the relation between the contextual, structural and instrumental dimensions of governance influence the evolution of productive agglomerations in the segment of gems and jewel. Method: Qualitative-descriptive research was, therefore, undertaken, applying the multiple case study method on two clusters. Originality/Relevance: The research fills the gap found in the research on clustering and systems dynamics and with the prospect of obtaining more reliable results on the evolution of the cluster's trajectory. Regarding the systemic view of agglomerations, especially around the topic of governance, there seems to be space for a research that involves multiple variables. Results: In both cases, the existence of natural resources was fundamental for the flow of incentives from the public authorities and the support institutions, and for the definition of scope and cooperation, which resulted in positive results for the participants. Over time, it was seen that the perception of limited collective benefits on the part of the players and the weak coordination resulted in the formation of subgroups, with specific interests. Theoretical/methodological contributions: The study employs a system dynamics approach, that highlights a non-linear relation between elements of a system, since this approach has had limited application in existing studies on the governance dynamics of productive agglomerations. The empirical results confirm the influence of the dimensions of governance on the evolution of the agglomerations, demonstrated by the relationships between the elements that compose them, which can inform the construction of scenarios for designing and anticipating future trajectories of productive agglomerations.

Copyright of Revista Producao Online is the property of Associacao Brasileira de Engenharia de Producao and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Producao Online is the property of Associacao Brasileira de Engenharia de Producao and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Producao Online is the property of Associacao Brasileira de Engenharia de Producao and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Environmental changes are understood under the geographic approach. It presupposes that environmental changes are a product of social, human and productive systems transformations, organized by ideological and political-economic conjunctures revealed like modification in dynamics of natural systems. We used statistical parameters of the annual fluviometric variability from 1947 to 2011 with representative points Tibagi, Ivaí, Piquiri and Iguaçu rivers, combined with historical evidence contextualised within the scope of territorial development policies in Paraná State. The analysis indicated patterns, tendencies and ruptures similar since 1960s. Associations of these results suggest convergences with transformations in the field, associated mainly with the period of the Green Revolution, that reinforted substitution of natural vegetation, and changes in land use patterns on the transition from coffee to soybean cultivation. [ABSTRACT FROM AUTHOR]

In the pharmaceutical industry, value is being destroyed through longer product development times. Given that patent lives are (normally) fixed at 20 years, the double hit of increasing time to market is evident – higher R&D costs and less time at market before generic competitors are able to be released into the marketplace. The Policy implications are massive: A huge and permanent shift away from internal R&D towards partnerships, licensing deals and acquisitions of more innovative biotechnology companies. In this study, we build a system dynamics model of the product development pipeline for a single company operating in the pharmaceutical market. The study shows that in the presence of loss of value due to longer lead times, it is more advantageous to: (a) work faster to reduce the backlog of projects; (b) increase the number of projects started whenever it is possible reduce complexity in the pipeline; and also (c) the optimal decision on resource allocation is independent of the loss of value due to longer lead times.

In a social-environmental modeling course, students need to learn complementary skills that include the conceptualisation of a model, different modeling paradigms, computer pro- gramming, and the process of rigorously converting ideas and data into a computational program using a given toolkit. Such topics need to be taught in parallel in order to keep a heterogeneous audience motivated. Based on the experience with multidisciplinary au- diences, this paper describes a socio-environmental modeling course that explores three modeling paradigms: System dynamics, Cellular automata, and Agent-based modeling. We also present a small tutorial with some examples developed for the course.

Copyright of Revista Gestão & Tecnologia is the property of Revista Gestao & Tecnologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The objective of this study is to investigate a phenomenon that occurs in Brazil, specifically the spike in demand at the end of the sales period, known as the hockey stick phenomenon. This analysis will encompass the causes as well as the impacts of this phenomenon, in a way that allows alternative policies to be evaluated. Data was collected from a Brazilian branch of a large multinational in the non-durable consumer goods industry and in semi-structured interviews conducted face-to-face with executives of 26 clients. The data was used to generate a continuous simulation model based on the methods of systems dynamics. The findings showed that the phenomenon negatively impacted the manufacturer’s financial performance in the long term and indicated required changes necessary to remediate the phenomenon. This is an empirical study on the hockey stick phenomenon, a problem that affects diverse companies in Brazil. The study showed that companies should not assume the hockey stick phenomenon to be an exogenous problem; it showed that there are policies able to improve financial performance; and it provided ideas regarding ways to carry out the change process.

Among the preparation measures that enable the population to respond quickly and effectively to disasters, is the implementation of early warning systems. So, this paper aims to represent the complexity of the process of issuance of natural disasters early warnings and to check on if and how behavioral and underlying factors to decision making can impact the effectiveness of the alert. In order to support this study, a System Dynamics model for an early warning system will be developed, based on a case study applied to the National Center for Monitoring and Early Warning of Natural Disasters (CEMADEN). As a result, it is hoped to demonstrate to decision-makers and managers, through a systemic view of the process, like cause and effect relationships between important elements of decision making can affect the performance of the early warnings over time, as well as subsidize the adoption of strategic actions to correct eventual system failures, thus reducing the occurrence of false alerts, lost events and early warnings issued with delays. In addition, the developed model may result in an organizational learning and testing mechanism for strategic planning. [ABSTRACT FROM AUTHOR]

Brazil is rich in renewable sources that can be used for energy generation. The renewable source of energy generation predominantly in Brazil is hydropower. However, the availability of hydropower depends on the useful volume reserves, which is subject to rainfall. Consequently, wind power is a renewable source that is being integrated into the electricityinterconnected system in Brazil. The growth of wind power generation depends on the financial resources and the delays in transmission projects. Despite the Brazilian incentives policy in wind power, the insufficient of transmission infrastructure affects to electricity price in electricity market. This paper addresses the effects of the insufficient of transmission on electricity price through a simulation model. The developed model is implemented to analyze the region of North and Northeast Brazil. [ABSTRACT FROM AUTHOR]

Copyright of Future Studies Research Journal: Trends & Strategies is the property of Future Studies Research Journal: Trends & Strategies and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A tese deste trabalho é que as técnicas mais sofisticadas atualmente utilizadas pelos economistas para fazer previsões (métodos não estruturais de previsão, em geral, e modelos de detecção de mudanças de regime, em particular) não parecem realmente muito eficazes em prever mudanças radicais de regime como a que ocorreu na economia mundial recentemente. Assim, para aumentar seu grau de acurácia, parece razoável imaginar que tais técnicas devam ser complementadas por abordagens mais holísticas. O objetivo geral deste trabalho é mostrar que a metodologia de dinâmica de sistemas (system dynamics), que permite identificar os ciclos de feedback que comandam a dinâmica de sistemas complexos, parece estar especialmente bem-equipada para se tornar uma dessas abordagens complementares. Pretende-se, especificamente, apresentar um algoritmo sistêmico para identificar processos de mudança de regime como os que ocorrem quando uma economia, após anos de expansão continuada, sofre os efeitos da explosão de uma bolha financeira, como ocorreu recentemente.This paper argues that the sophisticated techniques presently used by economists to forecast macroeconomic variables behavior (non-structural forecasting methods, in general, and regime-switching models, in particular) do not seem much effective for anticipating radical regime shifts as recently happened in the world economy. Thus, in order to improve their accuracy, it seems that they should be complemented by more holistic approaches. The general purpose of the paper is to show that the system dynamics methodology, which allows identifying the critical feedback loops that drive complex systems' dynamics, seems to be especially fitted to be one of those complementary approaches. To reach that goal, we present a systemic algorithm which allows identifying regime shift processes as the ones that take place when an economy is hit by the effects of a financial bubble burst.

The impact of the installation of a large-scale photovoltaic (PV) system to the electric power grid management is analyzed in a series of two works: Part 1 and Part 2. The PV generation is estimated in Part 1. By applying the results of Part 1, the Guatemala’s electric power grid management is simulated with a virtually-installed large-scale PV system using a nonlinear analysis model in this work, Part 2. The thermal power plants reduced their operation in the simulation by installing the PV system, however the effect of the PV system installation to the plants is different in each thermal power plant. The contribution of the PV installation to the reduction of operation of the largest generation thermal plants is very limited or null, because of their high efficiency and low cost in operation. On the other hand, the middle-large generation thermal power plants reduce their operation after installing PV system in this simulation. The reduction of thermal plants’ operation becomes large, but its reduction gradient becomes small as the PV installing capacity becomes large.

No atual ambiente competitivo, a tomada de decisão tem se tornado uma tarefa cada vez mais complicada, envolvendo inúmeras variáveis, e suas relações, nem sempre claramente entendidas. Uma dessas relações, foco deste artigo, é a relação entre tamanho de lote de produção e lead time médio. Essa relação é amplamente conhecida na literatura específica sobre teoria de filas, porém o mesmo não acontece na prática em gestão de operações. Este artigo trata deste assunto, objetivando apresentar e comparar o efeito de seis programas de melhoria contínua em variáveis do chão de fábrica (variabilidade da chegada das ordens, variabilidade do processo, taxa de defeito, tempo até a falha, tempo de reparo e tempo de set up) na relação tamanho de lote × lead time em um ambiente de máquina única que fabrica múltiplos produtos. Isto é feito por meio de uma combinação das abordagens System Dynamics (Forrester, 1962) e Factory Physics (Hopp; Spearman, 2008). Dois conjuntos de experimentos são realizados: i) Uma melhoria de grandes proporções (50%) em cada uma das variáveis separadamente, como aquela que seria obtida por um grande investimento; ii) Uma pequena melhoria em todas as variáveis simultaneamente. Os resultados mostraram: (a) o efeito positivo de programas de melhoria contínua em variáveis do chão de fábrica no lead time; (b) a importância de se conhecer a curva tamanho de lote × lead time e o papel da redução de set up antes de se iniciarem programas de redução de tamanhos de lote; (c) que investir em pequenas melhorias em muitas variáveis de forma simultânea é uma política melhor, com relação ao lead time, do que realizar uma grande melhoria em somente uma variável; (d) algumas contribuições para um melhor entendimento de modernos paradigmas de gestão da produção, tais como Lean Manufaturing e Quick Response Manufacturing.Many modern manufacturing management approaches present relationships between variables on the shop floor, aiming to increase the manager’s intuition about manufacturing dynamics. One of these is the relationship between lot size and average lead time, which is studied in this paper. Although this general relationship is widely recognized, only a selected number of authors address this relationship in a practical manner. This paper presenta and compares the effect of six continuous improvement programs (arrival variability, process variability, quality (defect rate), time to failure, repair time, and set up time) on lot size × lead time relationship in a multi-product, single-machine environment, by means of a combination of System Dynamics (FORRESTER, 1962) and Factory Physics (HOPP and SPEARMAN, 2008) approaches. Two sets of experiments are performed in this paper: a) A large (50%) improvement in each parameter separately, as might be obtained by a significant one-time investment; b) a small improvement in all parameters simultaneously. The results showed: (a) the positive effect of continuous improvement in shop floor variables on lead time ; (b) the importance of knowing the lot size × lead time curve and the effect of set up reduction programs before beginning with lot size reduction program; (c) that investing in small improvements in several variables is preferable regarding lead time than investing in a large improvement in just one variable; (d) some insights about modern manufacturing management paradigms such as: Lean Manufacturing and Quick Response Manufacturing.

One of the greatest challenges in brand management lies in monitoring brand equity over time. This paper aimsto present a simulation model able to represent this evolution. The model was drawn on brand equity concepts developed by Aaker and Joachimsthaler (2000), using the system dynamics methodology. The use ofcomputational dynamic models aims to create new sources of information able to sensitize academics and managers alike to the dynamic implications of their brand management. As a result, an easily implementable model was generated, capable of executing continuous scenario simulations by surveying casual relations among the variables that explain brand equity. Moreover, the existence of a number of system modeling tools will allow extensive application of the concepts used in this study in practical situations, both in professional and educational settings

Este artigo tem por objetivo analisar a participação de mercado dos diferentes grupos estratégicos que compõem o setor de agências de internet no Brasil, bem como as mudanças decorrentes de alterações nas variáveis críticas de concorrência, tais como preço, investimento em propaganda, investimento em tecnologia e disponibilidade de mão-de-obra. Para tanto, será aplicado o método de simulação computacional, utilizando-se dinâmica de sistemas. A adoção desta técnica permitiu identificar padrões contra-intuitivos, o que se revelou acertado, principalmente no que concerne às análises sobre mudanças no grau de diferenciação entre os diferentes grupos estratégicos analisados.This paper aims to analyze the dynamics of market share of different strategic groups that are part of the internet agencies industry in Brazil as well as the changes due to modifications in its critical variables such as price, advertising and technology investment, and the availability of qualified human resources. For that reason the method of computer simulation, using system dynamics, was adopted. The adoption of this technique allowed identifying non-trivial patterns, especially the ones related to the analyses of the changes in the degree of differentiation between the different strategic groups.

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Copyright of Revista Producao Online is the property of Associacao Brasileira de Engenharia de Producao and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Producao Online is the property of Associacao Brasileira de Engenharia de Producao and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)