Showing papers in "Requirements Engineering in 2007"
TL;DR: The approach is used to detect and classify stakeholders’ quality concerns across requirements specifications containing scattered and non-categorized requirements, and also across freeform documents such as meeting minutes, interview notes, and memos.
Abstract: This paper describes a technique for automating the detection and classification of non-functional requirements related to properties such as security, performance, and usability. Early detection of non-functional requirements enables them to be incorporated into the initial architectural design instead of being refactored in at a later date. The approach is used to detect and classify stakeholders’ quality concerns across requirements specifications containing scattered and non-categorized requirements, and also across freeform documents such as meeting minutes, interview notes, and memos. This paper first describes the classification algorithm and then evaluates its effectiveness through reporting a series of experiments based on 30 requirements specifications developed as term projects by MS students at DePaul University. A new and iterative approach is then introduced for training or retraining a classifier to detect and classify non-functional requirements (NFR) in datasets dissimilar to the initial training sets. This approach is evaluated against a large free-form requirements document obtained from Siemens Logistics and Automotive Organization. Although to the NFR classifier is unable to detect all of the NFRs, it is useful for supporting an analyst in the error-prone task of manually discovering NFRs, and furthermore can be used to quickly analyse large and complex documents in order to search for NFRs.
224 citations
TL;DR: An exploratory study which provides insight into industrial practices with respect to requirements engineering (RE), using semi-structured interviews and a detailed questionnaire from 28 software projects in 16 Australian companies to give insight into the gap between RE theory and practice.
Abstract: Empirical studies have demonstrated that requirements errors introduced during software development are most numerous in the software life-cycle, making software requirements critical determinants of software quality. This article reports an exploratory study which provides insight into industrial practices with respect to requirements engineering (RE). A combination of both qualitative and quantitative data is collected, using semi-structured interviews and a detailed questionnaire from 28 software projects in 16 Australian companies. The contribution of this RE study is threefold: Firstly, it includes a detailed examination of the characteristics of the RE activities involved in the projects. Secondly, it reconstructs the underlying practiced process models. Thirdly, it compares these models to one another and with a number of well-known process models from RE literature to give insight into the gap between RE theory and practice.
87 citations
TL;DR: This article presents multi-level feature trees, which offer a compromise between a single global and several smaller, independent feature trees and describes scenarios showing how this concept can be put into practice.
Abstract: Feature modeling has become a popular technique for domain analysis and variability management. However, it is still a considerable challenge to apply this technique to product families and organizational contexts of high complexity like the product range of a global automotive corporation. Managing everything as a single product family with a global feature tree is virtually impossible owing to the enormous complexity, but if the product range is split up into several smaller, independent product lines with separate feature models, systematic reuse and strategic variability management across these portions is lost. In this article, we present multi-level feature trees, which offer a compromise between a single global and several smaller, independent feature trees. Other development artifacts may also be arranged in this way if the multi-level concept is adapted to them. This is shown exemplarily for requirements artifacts in Telelogic Doors. Finally, we describe scenarios showing how this concept can be put into practice.
66 citations
TL;DR: A technique is presented for obtaining a specification from a requirement through a series of incremental steps, involving a decomposition of the environment into interconnected domains and a formal requirement on phenomena of those domains.
Abstract: A technique is presented for obtaining a specification from a requirement through a series of incremental steps. The starting point is a Problem Frame description, involving a decomposition of the environment into interconnected domains and a formal requirement on phenomena of those domains. In each step, the requirement is moved towards the machine, leaving behind a trail of “breadcrumbs”—partial domain descriptions representing assumptions about the behaviors of those domains. Eventually, the transformed requirement references only phenomena at the interface of the machine and can therefore serve as a specification. Each step is justified by a mechanically checkable implication, ensuring that, if the machine obeys the derived specification and the domain assumptions are valid, the requirement will hold. The technique is formalized in Alloy and demonstrated on two examples.
57 citations
TL;DR: An industrial evaluation of the requirements abstraction model is presented and it is concluded that the model provides helpful improvements to the industrial requirements engineering process.
Abstract: Software requirements are often formulated on different levels and hence they are difficult to compare to each other. To address this issue, a model that allows for placing requirements on different levels has been developed. The model supports both abstraction and refinement of requirements, and hence requirements can both be compared with each other and to product strategies. Comparison between requirements will allow for prioritization of requirements, which in many cases is impossible if the requirements are described on different abstraction levels. Comparison to product strategies will enable early and systematic acceptance or dismissal of requirements, minimizing the risk for overloading. This paper presents an industrial evaluation of the model. It has been evaluated in two different companies, and the experiences and findings are presented. It is concluded that the requirements abstraction model provides helpful improvements to the industrial requirements engineering process.
57 citations
TL;DR: This paper conducts a systematic study of cognitive complexity to reveal important factors pertaining to data modeling and implications and recommendations on how to address cognitive complexity caused by data modeling.
Abstract: Data modeling is a complex task for novice designers. This paper conducts a systematic study of cognitive complexity to reveal important factors pertaining to data modeling. Four major sources of complexity principles are identified: problem solving principles, design principles, information overload, and systems theory. The factors that lead to complexity are listed in each category. Each factor is then applied to the context of data modeling to evaluate if it affects data modeling complexity. Redundant factors from different sources are ignored, and closely linked factors are merged. The factors are then integrated to come up with a comprehensive list of factors. The factors that cannot largely be controlled are dropped from further analysis. The remaining factors are employed to develop a semantic differential scale for assessing cognitive complexity. The paper concludes with implications and recommendations on how to address cognitive complexity caused by data modeling.
39 citations
TL;DR: An explanatory conceptual framework is derived, based on an extension of the “method-in-action” model, the application to WBSD has not been previously investigated in depth and it is proposed that this framework of WBSD issues is valuable in a number of ways to educators, researchers, practitioners, and method engineers.
Abstract: This paper reports the findings of a detailed study of Web-based systems design (WBSD) practices in Ireland based on data collected over a 3-year period (2002–2005), the objectives of which were to (1) contribute towards a richer understanding of the current “real-world” context of WBSD by characterising the profile of a typical project (team size, timeframe, nature of requirements, etc.) and identifying the key challenges, constraints, and imperatives (i.e. “mediating factors”) faced by Web-based system designers, and (2) understand how those contextual parameters and mediating factors influence the activity of WBSD as regards the selection and enactment of whatever design practices are therefore engaged (i.e. the use of methods, procedures, etc.). Data was gathered through a survey which yielded 165 usable responses, and later through a series of semi-structured qualitative interviews. Using grounded theory, an explanatory conceptual framework is derived, based on an extension of the “method-in-action” model, the application of which to WBSD has not been previously investigated in depth. It is proposed that this framework of WBSD issues is valuable in a number of ways to educators, researchers, practitioners, and method engineers.
27 citations
TL;DR: A decision support approach that aims at addressing COTS mismatches during and after the selection process, called MiHOS (Mismatch Handling for COTS Selection), that is integrated with existing COTS selection methods.
Abstract: In the process of selecting Commercial Off-The-Shelf (COTS) products, it is inevitable to encounter mismatches between system requirements and COTS products. These mismatches occur as a result of an excess or shortage of the COTS attributes. This paper proposes a decision support approach, called MiHOS (Mismatch Handling for COTS Selection), that aims at addressing COTS mismatches during and after the selection process. MiHOS can be integrated with existing COTS selection methods at two points: (1) For evaluating COTS candidates: MiHOS estimates the anticipated fitness of the candidates if their mismatches are resolved. This helps to base our COTS selection decisions on the fitness that the candidates will eventually have if selected. (2) Mismatch resolution after selecting a COTS product: MiHOS suggests alternative plans for resolving the most appropriate mismatches using suitable actions, such that the most important risk, technical, and resource constraints are met. A case-study is used to illustrate MiHOS and to discuss its added value.
25 citations
TL;DR: The purpose of this essay is to describe what it is that a BA does, and to compare this with the role of a ‘‘requirements engineer’’, to highlight a particular approach to the job of business analysis, that may be of use in the work of other BAs and requirements engineers.
Abstract: This essay has its origins in a conversation at a recent requirements engineering (RE) conference, where I suggested that much of the material under discussion would be familiar to industry practitioners in Australia, but that this work would be recognised as part of the job role of ‘‘business analyst’’ (BA). The purpose of this essay is to describe what it is that a BA does, and to compare this with the role of a ‘‘requirements engineer’’. My contention is that, although there is patently overlap with RE, the practice of business analysis includes other activities that appear to be outside the scope of RE. Requirements engineers reading this essay may disagree—they may consider that the job functions I describe are all legitimate parts of current RE practice. Rather than form an exact conclusion about the extent of the business analysis domain, this essay aims to describe the focus of my role as a BA, and to highlight a particular approach to the job of business analysis, that may be of use in the work of other BAs and requirements engineers.
18 citations
TL;DR: The Green Revolution can be seen as a technological paradigm originated from developments in chemistry and biology, determining a technological path of extensive use of chemical inputs (fertilizers and pesticides) since the 1970's, especially with the identification of environmental problems caused by chemical residues and the growth limits of the chemicals industry as discussed by the authors.
Abstract: The Green Revolution can be seen as a technological paradigm originated from developments in chemistry and biology, determining a technological path of extensive use of chemical inputs (fertilizers and pesticides) Since the 1970’s, the limits of the Revolution have become apparent, especially with the identification of environmental problems caused by chemical residues and the growth limits of the chemicals industry Developments in biotechnology have led to techniques that overcome genetic barriers found by traditional techniques If, on the one hand, such change has led us beyond the limits of the Green Revolution, on the other hand it allowed the diversification of firms in the chemicals industry The point discussed here is whether this new technology will reduce the use of chemical inputs or simply resume the old paradigm with new tools, under an industry strategy of increasing the value of its assets
16 citations
TL;DR: Case studies evaluating a method of unifying use cases to derive a unified statechart model of the behavior of the domain of a proposed computer-based system independently confirm some of the benefits of building a unified SC mentioned in the works of Glinz; Whittle and Schumann; and Harel, Kugler, and Pnueli.
Abstract: This paper presents the results of case studies evaluating a method of unifying use cases (UCs) to derive a unified statechart model of the behavior of the domain of a proposed computer-based system. An evaluation of the unification method, the obtained statechart model of the domain, the method’s and model’s feedback on the UCs themselves, and how the method is used in requirements engineering practice was carried out by examining 58 software requirements specifications produced by 189 upper-year undergraduate and graduate students. The results of these studies independently confirm some of the benefits of building a unified SC mentioned in the works of Glinz; Whittle and Schumann; and Harel, Kugler, and Pnueli.
TL;DR: The design and implementation of a smart agent-enabled system for personalizing wireless mobile services and advertisements for Java 2 Micro Edition or Java ME, and Wireless Application Protocol (WAP) enabled devices is presented.
Abstract: Wireless mobile services are computing applications that run on handheld wireless devices. Such applications must work within the daunting constraints of the devices, which include memory, processing power, input capabilities, and size of display. It is therefore important that mobile services take into account the user’s context, optimize resource usage, and minimize input effort imposed on the user. In this paper, we present the design and implementation of a smart agent-enabled system for personalizing wireless mobile services and advertisements for Java 2 Micro Edition (J2ME) or Java ME, and Wireless Application Protocol (WAP) enabled devices. We use software agents for context filtering because such autonomous software entities have characteristics that can benefit mobile devices and the wireless environment, and the Composite Capability/Preference Profiles (CC/PP) standard for defining profiles for user preferences and device capabilities. The system incorporates the use of artificial neural networks to adaptively and iteratively learn to select the best available service based on contextual information. The system is evaluated using practical operating scenarios, as well as empirical data and results show an 87% success rate in the selection of the best available service.
TL;DR: The authors argue that Latin American science and technology policy can be better understood by modeling these three distinct approaches, and that it is possible to make an association between them and some specific interests, which are linked to different political projects.
Abstract: The analytical and conceptual matrix that marked scientific and technological policies after World War II is associated with a linear perspective on the relations between science, technology and development. This view is still popular among policy makers. There are, however, three approaches that criticize this particular view: the Evolutionary approach, the Latin American Thought in Science, Technology and Society (PLACTS), and what we call the Alternative View. In this paper, we argue that Latin American science and technology policy can be better understood by modelling these three distinct approaches, and that it is possible to make an association between them and some specific interests, which are linked to different political projects.
TL;DR: In this paper, the main goal of this paper is to describe Northeast, North and Mid-West Constitutional Financing Fund loans by municipalities, investigating if the resources allocations of the funds are concentrated in the most dynamic municipalities and if there are concentration loans for groups of municipalities.
Abstract: The main goal of this paper is to describe Northeast, North and Mid- West Constitutional Financing Fund loans by municipalities, investigating if the resources allocations of the funds are concentrated in the most dynamics municipalities and if there are concentration loans for groups of municipalities. In this investigation, among other analyses, we describe the fund resource supply and loans by municipalities. The main conclusion of this paper shows that the Constitutional Financing Fund loans have not been directed to the poorest municipalities.
TL;DR: In this paper, the authors present findings of a survey of 133 corporate buyers from about 130 companies on the use of readily available web-based systems for business-to-business transactions and the requirements perceived to be critical to the effective support of supply chain operations.
Abstract: World Wide Web (WWW)-based electronic commerce has emerged as a mean to conduct business transactions that were previously handled through traditional interorganizational systems, phone, fax, on-site visits, or mail. Today, electronic procurement (e-procurement) accounts for most of the volume and value of the business transactions conducted over the Internet. As of yet, however, little or no research has assessed the functional and non-functional requirements sought for the WWW-based systems used to support the procurement process. This paper, presents findings of a survey of 133 corporate buyers from about 130 companies on the use of readily available web-based systems for business-to-business transactions and the requirements perceived to be critical to the effective support of supply chain operations.
TL;DR: In this article, the performance of the textile-clothing sector in Parana and its specialized regional segments between 2000 and 2004 is discussed, where the authors analyze the changes in the sector structure and the elements composing the Local Productive Arrangements.
Abstract: The present article discusses the performance of the textile-clothing sector in Parana and its specialized regional segments between 2000 and 2004. The study seeks to characterize the productive specialization and identify the existing stages of the textile-clothing chain in the State specialized regions. The article analyzes the changes in the sector structure and the elements composing the Local Productive Arrangements. The results show that the importance of the Parana textile group has decreased after the cotton culture crisis in 1990, except for silk production that still resists despite little improvement. The clothing group has improved greatly, mainly concerning the so called “Fashion Corridor” in the north/northwest side of the State where we can find the most important jeans and cap producers in Brazil.
TL;DR: In this article, the authors used the estimated coefficients of the physical attributes and of the location of the rented houses to estimate the estimated rent value for owned houses, and concluded that there was an expressive improvement in the shape of distribution of wealth ownership in this period.
Abstract: From the PNAD´s data covering 1995 and 2004 this paper estimates the value of house rents. Using the estimated coefficients of the physical attributes and of the location of the rented houses, we impute an “estimated rent value” for owned houses. In following, admitted constant the relation between rents and value of stock, we estimate the real value of house stock for those years. Based on PNAD´s data on received rents. We also distribute to each family the corresponding value of stock in properties. Excluding the families that do not have any property and are able to pay rent corresponding to properties which price is higher than the average price of rented houses, the Index of Gini is calculated for both years. The paper concludes that there was an expressive improvement in the shape of distribution of wealth ownership in this period, since the Gini coefficient had changed from 0,69 to 0,61 between 1995 and 2004.
TL;DR: For information systems engineering field to continue to strive and flourish, it needs to continuously embrace new ideas, employ innovative research methods, and develop theories that are unique to ISE.
Abstract: What does the future hold for information systems engineering field? Are we going to see major revolution taking place or are we going to see incremental evolution? Can the history of information systems engineering field provide us some enlightenment? A panel was asked to examine this issue at the International Conference on Advanced Information Systems Engineering (CAiSE’07) held in Trondheim, Norway. The following is the author’s view on the topic. What does the future hold for information systems engineering (ISE) field? First, what is the definition of information systems engineering? I would define information systems engineering as a field that combines the knowledge of information systems concepts, computer technologies, human cognition, engineering and scientific principles, and empirical and non-empirical methods to analyze, design, implement, and manage information systems. Although ISE combines knowledge from many disciplines, ISE is a unique field and a field by itself. I hesitate to call ISE a multi-disciplinary field as such a categorization has the connotation that ISE can be done in many disciplines and by researchers from other disciplines. ISE is a separate discipline and has a unique place in the academic structure. Why do I start by defining ISE? I believe that for information systems engineering field to continue to strive and flourish, we need to define ISE broadly. We need to continuously embrace new ideas, employ innovative research methods, and develop theories that are unique to ISE.
TL;DR: The economic approach of tourism demand and the market evidence for domestic tourism in Brazil are emphasized.
Abstract: Tourism is now one of the most important economic activities in the world. Behind it, there are several components and motivations for “a trip.” The consumer’s choice of tourism products has been approached in the literature from different perspectives. This article emphasizes the economic approach of tourism demand and the market evidence for domestic tourism in Brazil.
TL;DR: The economic analysis of crime, security and violence is based upon the original article by Gary S. Becker whose title is Crime and Punishment: an economic approach as mentioned in this paper, which assumes that the criminal activity is the result of some social parameters and then searches for an optimal situation from the social viewpoint, which is defined as the situation of minimum total cost.
Abstract: The economic analysis of crime, security and violence is based upon the original article by Gary S. Becker whose title is Crime and Punishment: an economic approach. The central piece of Becker’s theoretical model is the economic reasoning of comparing gains and costs from de individual’s point of view. Becker assumes that the criminal activity is the result of some social parameters and then searches for an optimal situation from the social viewpoint, which is defined as the situation of minimum total cost. Crime, security and violence have acquired such an importance in the 21st Century that a reflection on the Becker’s model is required in order to give scientific basis to developing and adopting more effective public policies. This article aims to lend a hand to that reflection by presenting a significant set of inquiries.
TL;DR: In this paper, the authors analyze the impact of different modalidades of implementación on the risk of riegos in the Cash Flow at Risk (CFA) model.
Abstract: Los contratos bilaterales que se celebran entre Agentes del mercado electrico ecuatoriano, obedecen a varias modalidades de implementacion, entre las principales: “pague lo demandado”, “pague lo contratado”, “pague lo producido con tope”. Cada una de estas modalidades de contrato, involucra distintos niveles de riesgo para los vendedores y compradores, estos riesgos estan relacionados con la volatilidad del precio de la energia en el mercado spot, con la produccion programada de una central, con el pronostico de la demanda y otros factores adicionales.
El exito o fracaso resultante de la implementacion de un contrato depende en gran medida de la gestion de riesgo que hagan las empresas participantes, por tal motivo, es importante analizar las diferentes herramientas para cuantificacion de riegos, tal como “Cash Flow at Risk”. Estas herramientas permiten la cuantificacion del riesgo existente en un negocio a traves de varios indicadores.
TL;DR: In this paper, the authors analyzed the contribution of the household pensions on the inequality of income distribution in Brazil, Rural Brazil, State of Parana and Rural Parana, in the period 1992 - 2003.
Abstract: This work analyzes the participation and the contribution of the household pensions on the inequality of income distribution in Brazil, Rural Brazil, State of Parana and Rural Parana, in the period 1992 - 2003. The paper reviews the literature on social politics and social welfare and uses the methodology of decomposition of the Gini index: revenue of the main work, revenue of other works, pensions, donations, rent revenues and other revenues (interests, dividends, etc.). The results show growing participation of pensions in the years after 1992, explained by the social and economical policies of the period. The contribution of that portion of household revenue for the concentration of income is significant for Brazil and rural Brazil in the last five years analyzed. Parana thwarted the Brazilian reality, showing the non contribution of pensions for the concentration of income in the State, except for 2002. In the rural space, however, the concentration of income was produced by that portion of revenue in the years 1992, 1998 and 2002.
TL;DR: The tenth anniversary AWRE was exceptional in this sense since the two keynote speakers were both from industry too, and Robert Shedden from Spotless, and Jason Rubens from Novell, Australia, delivered two very interesting and thought provoking talks and were subsequently invited to write articles based on their speeches, which are presented in this issue of the requirements engineering journal to celebrate the 10th year anniversary of AWRE.
Abstract: The Tenth year anniversary of the Australian workshop on requirements engineering took place in Melbourne, Australia on 22 November 2005. This annual meeting of Australian RE researchers and practitioners was inaugurated in 1996 as a result of increasing interest in RE around the world in general, and in Australia in particular. Its emergence signaled the need for a forum to express and exchange ideas, viewpoints and to facilitate the growth of the RE community in Australia. It has been gratifying to observe the consolidation and growth of RE research community facilitated by this workshop over the last 10 years. The workshop has provided an opportunity for both established researchers as well as research students to become informed of new research projects as well as the progress of existing projects on annual basis. Furthermore, every year AWRE has attracted submissions and presentations of many researchers from other parts of the world to further enrich the experience of the attendees. We have also had the privilege of welcoming internationally recognized keynote speakers from the RE research community to AWRE over the years. Although the attendance of the workshop has been modest to compare with international conferences but it prides itself with the reputation of being very interactive, friendly and productive. One of the unique features of AWRE series has been the unified gathering of many researchers from information systems, software engineering and systems engineering communities. A goal that we believe has not been effectively achieved in the international RE conferences. The tenth AWRE also marked the inauguration of the Australian Computer Society’s National Technical Committee on Requirements Engineering. This is yet another testimony to the successful achievement of the original goal of AWRE to facilitate the building of an Australian RE community of interest. The Australian workshop on RE has always attracted adequate representations from the computing industry. The tenth anniversary AWRE was exceptional in this sense since the two keynote speakers were both from industry too. Robert Shedden from Spotless, and Jason Rubens from Novell, Australia, delivered two very interesting and thought provoking talks [1] and were subsequently invited to write articles based on their speeches. These two articles went through several rounds of editing. One of these articles is thus presented in this issue of the requirements engineering journal to celebrate the 10th year anniversary of AWRE. I hope you will find this article insightful. We hope that the success of the AWRE series will continue in the years to come. We plan to extend it to cover submissions and attract more attendees from the Asia-Pacific region. The 11th AWRE will be held in Adelaide, South Australia (http://www.awre2006.cis. unisa.edu.au/) on 9 December 2006 and 12th AWRE will be in Brisbane, Queensland in September 2007.
TL;DR: Toda negociación entre países tiene un punto de equilibrio distinto que tiene que ver with the valorización que cada parte hace of los beneficios obtenidos y the fortaleza con la que enfrenta la negociationón.
Abstract: El proceso de integracion regional realizado en la CAN fue un proceso muy participativo que tiene un hito fundamental en la Decision CAN 536 donde se establecen las directivas generales en base a las cuales se establecieron e implementaron los acuerdos de interconexion y el cuerpo reglamentario y regulatorio vigente actualmente en Ecuador, Colombia y Peru. Toda negociacion entre paises tiene un punto de equilibrio distinto que tiene que ver con la valorizacion que cada parte hace de los beneficios obtenidos y la fortaleza con la que enfrenta la negociacion.
Un ejemplo de ello es por ejemplo la integracion en el MERCOSUR donde Brasil acepto que la venta de energia electrica desde Argentina sea por contrato y a riesgo de los inversores produciendose la misma a un precio cercano al costo de oportunidad de Brasil al mismo momento que Argentina vendia su gas a su costo de oportunidad y no al de Chile que era el comprador. Estos beneficios nunca son explicitados y valorizados objetivamente porque dependen de las alternativas futuras disponibles; y por lo tanto, muy subjetivas, si se analizan a futuro y mucho mas si se desean analizar en relacion a interconexiones en servicio.
TL;DR: This special issue of the Requirements Engineering Journal contains three articles that are extended and enhanced versions of papers presented at RE’06, the 14th IEEE International Requirements Engineering Conference, which was held September 11–15, 2006 in Minneapolis, Minnesota, USA.
Abstract: The IEEE International Requirements Engineering Conference, which is the premier conference in the field of requirements engineering, has a tradition of publishing the best research papers of the conference in a special issue of the Requirements Engineering Journal. This special issue contains three articles that are extended and enhanced versions of papers presented at RE’06, the 14th IEEE International Requirements Engineering Conference, which was held September 11–15, 2006 in Minneapolis, Minnesota, USA. RE’06 was a big success, bringing together over 300 researchers, practitioners, students, and educators from 25 countries all over the world, thereby illustrating the growing importance of requirements engineering in software and systems development. The theme of RE’06 was ‘‘understanding the stakeholders’ desires and needs’’, thus reflecting the fact that, at its core, requirements engineering is about satisfying the stakeholders. The conference theme also spawned a special issue of IEEE Software on Stakeholders in Requirements Engineering [1], where two articles originate from RE’06 papers. The papers and discussions at the conference did not focus on a specific ‘‘hot topic’’. Rather, RE’06 revealed a continued interest in standard requirements engineering topics such as elicitation, goals, analysis, languages, tools, stakeholders, etc., with some increased interest in aspectual requirements, non-functional requirements, and goals. The complete set of papers can be found in the conference proceedings [2], which are also electronically available from the IEEE Computer Society Digital Library. We deliberately shaped RE’06 as a conference not purely for academic researchers, but for any person interested in requirements engineering. So the two research paper tracks were complemented by a full-fledged practitioner track. The three keynote talks by Mary Beth Rosson (Pennsylvania State University) on end users who meet their own requirements, Dorothy Graham (Grove Consultants, UK) on testing to improve requirements, and John Mylopoulos (University of Toronto and Università di Trento) on goal-oriented requirements engineering covered both academic and practical issues of requirements engineering. Tutorials and mini-tutorials added an educational component. The aspect of exchanging ideas and discussing issues was fostered by longer presentation slots which permitted more and livelier discussion of presented papers, a birds-of-a-feather session, and workshops held in conjunction with the conference. From 179 submissions, the RE’06 Program Committee and Program Board had selected 39 papers in five paper categories for presentation at the conference and inclusion in the proceedings. From the accepted research papers, the authors of four papers were invited to submit their work for this special issue. These submissions underwent a standard REJ reviewing process. Members of the RE’06 Program Committee as well as external experts served as reviewers. Three submissions were accepted for publication in this issue, the fourth one has been withdrawn. The article ‘‘Multi-level feature trees: a pragmatic approach to managing highly complex product families’’ by Mark-Oliver Reiser and Matthias Weber describes an approach for making feature trees manageable for large M. Glinz (&) Department of Informatics, University of Zurich, Binzmühlestrasse 14, 8050 Zurich, Switzerland e-mail: glinz@ifi.uzh.ch
TL;DR: The presente estudio tiene el proposito of realizar un analisis comparativo of los distintos metodos existentes y mostrar the fundamento teorico of cada uno of ellos.
Abstract: Las senales que se obtienen a traves de la diferenciacion espacial de los precios nodales, no han logrado su proposito de incentivar la ubicacion optima de nueva generacion en la red. Por otro lado, la remuneracion al transportista que se obtiene por la diferencia de cobros y pagos debido a la aplicacion de factores de nodo, no es suficiente para cubrir la totalidad de cargos regulados del transportista, siendo necesario la aplicacion de cargos complementarios.
A traves de las reformas a la LRSE, se unifican los precios nodales con las componentes de energia y potencia. Debido a las perdidas de transmision, cuando se igualan los precios nodales, el mercado no cierra financieramente, siendo necesario establecer metodos para la asignacion de las perdidas.
Diversos son los metodos que se han propuesto para la asignacion de las perdidas, acogiendose a distintos criterios tecnicos.
El presente estudio tiene el proposito de realizar un analisis comparativo de los distintos metodos existentes y mostrar el fundamento teorico de cada uno de ellos.
Luego se analizara la propuesta de eliminacion de factores de nodo desde el punto de vista de las liquidaciones que resulten con la implementacion de cada uno de los metodos analizados.
Las senales que se obtienen a traves de la diferenciacion espacial de los precios nodales, no han logrado su proposito de incentivar la ubicacion optima de nueva generacion en la red. Por otro lado, la remuneracion al transportista que se obtiene por la diferencia de cobros y pagos debido a la aplicacion de factores de nodo, no es suficiente para cubrir la totalidad de cargos regulados del transportista, siendo necesario la aplicacion de cargos complementarios.
A traves de las reformas a la LRSE, se unifican los precios nodales con las componentes de energia y potencia. Debido a las perdidas de transmision, cuando se igualan los precios nodales, el mercado no cierra financieramente, siendo necesario establecer metodos para la asignacion de las perdidas.
Diversos son los metodos que se han propuesto para la asignacion de las perdidas, acogiendose a distintos criterios tecnicos.
El presente estudio tiene el proposito de realizar un analisis comparativo de los distintos metodos existentes y mostrar el fundamento teorico de cada uno de ellos.
Luego se analizara la propuesta de eliminacion de factores de nodo desde el punto de vista de las liquidaciones que resulten con la implementacion de cada uno de los metodos analizados.
TL;DR: In this article, the authors analyze the Brazilian fiscal federalism from the Old Republic to the first years of the 21st century and show the predominance of non cooperatives federative relations between the Brazilian states, road-of-rule, with very little coordination degree.
Abstract: This article analyzes the Brazilian fiscal federalism from the Old Republic to the first years of the 21st century. It stresses three time periods. The first, until the beginning of the sixties, is marked by the constitution of a base industry and of a mass internal market. The second runs under an industrial dynamics associated with the authoritarian regime. The third begins with the transition towards democracy consolidation. Besides the complex subject of the used division of stages, the article shows the predominance of non cooperatives federative relations between the Brazilian states, road-of-rule, with very little coordination degree. Meanwhile, the validity of a tradition local of the states interrupted during good part of the authoritarian regime and, more recently, weakened by a process of fiscal decentralization. The article concludes questioning the capacity of the State and of the federated beings of assisting to the social demands in an atmosphere through the new social actors existence.
TL;DR: Two posibles aplicaciones de la Inteligencia Artificial se muestra en base a un modelo neuro – fuzzy (ANFIS), a los Sistemas de Suministro de Energía Eléctrica (SSEE).
Abstract: En este trabajo se muestra dos posibles aplicaciones de la Inteligencia Artificial (IA), en base a un modelo neuro – fuzzy (ANFIS), a los Sistemas de Suministro de Energia Electrica (SSEE). Se utiliza IA debido a las ventajas de modelacion, en lo que respecta con sistemas multivariable, y tiempo de calculo. El modelo ANFIS aprende las relaciones pasadas, actuales y futuras de la demanda y los precios.
Se analiza ademas el performance del Modelo ANFIS comparado con una Metodologia de referencia (ARIMA).