Moss and liverwort epiphytes on trunks of Cyathea delgadii in a fragment of tropical rain forest, São Paulo State, Brazil

This study is a survey of the bryophyte species that occur on the trunks of Cyathea delgadii Sternb. (Cyatheaceae), a native tree fern, encountered in a fragment of Atlantic forest located in the area of the „Parque Estadual das Fontes do Ipiranga (PEFI)“, São Paulo State, Brazil. Specimens of bryophytes were collected from March 2001 to October 2003. We found 35 bryophyte species (12 spp. of mosses and 23 of liverworts). Ceratolejeuenea dentacornuta Steph. is presented as a new record for Brazil. A brief discussion about previous records of bryophyte species growing on trunks of tree ferns in Brazil is also presented

Bryophytes from restinga in Setiba State Park, Espírito Santo State, Brazil

A total of 34 bryophyte species were identified (25 hepatics, 9 mosses) from restinga at Setiba State Park, Guarapari Municipality, Espírito Santo State, Brazil. Several species reported previously from restinga appear to be erroneous records, based on misidentification

Bryophytes of Rio Branco Municipality, Acre, Brazil

A survey of the bryophyte flora of Rio Branco Municipality, State of Acre, Brazil, has revealed a total of 76 species of bryophyte; 66 are new records for the State of Acre and two hepaticas, Cololejeunea dzumacensis P. Tix. and Lejeunea bermudiana (Evs.) Schust., are new records for Brazil. The Anthocerotae are represented only by Notothylas vitalii Udar & Singh

Flexible Job-shop Scheduling Problem with Sequencing Flexibility: Mathematical Models and Solution Algorithms

Marketing strategists usually advocate increased product variety to attend better market demand. Furthermore, companies increasingly acquire more advanced manufacturing systems to take care of the increased product mix. Manufacturing resources with different capabilities give a competitive advantage to the industry. Proper management of the current productions resources is crucial for a thriving industry. Flexible job shop scheduling problem (FJSP) is an extension of the classical Job-shop scheduling problem (JSP) where operations can be performed by a set of candidate capable machines. An extended version of the FJSP, entitled FJSP with sequencing flexibility (FJSPS), is studied in this work. The extension considers precedence between the operations in the form of a directed acyclic graph instead of sequential order. In this work, a mixed integer programming (MILP) formulation is presented. A single objective formulation to minimize the weighted tardiness for the FJSP with sequencing flexibility is proposed. A different objective to minimize makespan is also considered. Due to the NP-hardness of the problem, a novel hybrid bacterial foraging optimization algorithm (HBFOA) is developed to tackle the FJSP with sequencing flexibility. It is inspired by the behaviour of the E. coli bacteria. It mimics the process to seek for food. The HBFOA is enhanced with simulated annealing (SA). The HBFOA has been packaged in the form of a decision support system (DSS). A case study of a small and medium-sized enterprise (SME) manufacturing industry is presented to validate the proposed HBFOA and MILP. Additional numerical experiments with instances provided by the literature are considered. The results demonstrate that the HBFOA outperformed the classical dispatching rules and the best integer solution of MILP when minimizing the weighted tardiness and offered comparable results for the makespan instances. In this dissertation, another critical aspect has been studied. In the industry, skilled workers usually are able to operate a specific set of machines. Hence, managers need to decide the best operation assignments to machines and workers. However, they need also to balance the workload between workers while accomplishing the due dates. In this research, a multi-objective mathematical model that minimizes makespan, maximal worker workload and weighted tardiness is developed. This model is entitled dual-resource FJSP with sequencing flexibility (DRFJSPS). It covers both the machine assignment and also the worker selection. Due to the intractability of the DRFJSPS, an elitist non-dominated sorting genetic algorithm (NSGA-II) is developed to solve this problem efficiently. The algorithm provides a set of Pareto-optimal solutions that the decision makers can use to evaluate the trade-offs of the conflicting objectives. New instances are introduced to demonstrate the applicability of the model and algorithm. A multi-random-start local search algorithm has been developed to assess the effectiveness of the adapted NSGA-II. The comparison of the solutions demonstrates that the modified NSGA-II provides a non-dominated efficient set in a reasonable time. Finally, a situation where there are multiple process plans available for a specific job is considered. This scenario is useful to be able to react to the current status of the shop where unpredictable circumstances (machine breakdown, current product mix, due dates, demand, etc.) can be accurately tackled. The determination of the process plan also depends on its cost. For that, a balance between cost, and the accomplishment of due dates is required. A multi-objective mathematical model that minimizes makespan, total processing cost and weighted tardiness are proposed to determine the sequence and the process plan to be used. This model is entitled flexible job-shop scheduling problem with sequencing and process plan flexibility (FJSP-2F). New instances are generated to show the applicability of the model

A Resource Based View of the Information Systems Sourcing Mode

This paper studies the relationships between the choice of a sourcing mode for information systems, the value of the resources used in systems development activities and the presence of those resources at sufficient level within the firm. The objective is to better understand the factors underlying the decision to keep the development of an information system inside the firm or to entrust it to an outside partner. A sourcing model is proposed using the resource-based theory. Two case studies drawn from a larger study are used to illustrate the concepts used in the research model. Data from these two projects illustrate how the model could be used to predict the sourcing mode retained by the managers for each project, given the availability of the necessary resources and the strategic value of the future system. Cette recherche tente de mesurer le lien entre le mode de gestion d'une activité (gestion interne ou impartition) et la valeur de l'activité d'une part, et la présence des ressources requises dans l'entreprise d'autre part. L'objectif est de mieux comprendre les facteurs sous-jacents à une décision d'internalisation ou d'impartition d'une activité. Deux cas sont présentés. Ces cas traitent de développement de systèmes informatiques. Ils permettent d'illustrer le pouvoir explicatif du modèle. Les données illustrent bien comment le modèle proposé peut être utilisé pour prédire le mode de gestion approprié d'une activité de développement de systèmes informatique.Resource-based theory, software development, outsourcing, management of software development projects, Théorie fondée sur les compétences, développement de logiciels, impartition, gestion de projets de développement de systèmes

A Resource-Based Analysis of Outsourcing: Evidence from Case Studies

The central role that information technology plays in the management of companies, the massive investments that are required, and a preoccupation for rationalization explain in good part the renewed interest in the strategies used for information systems sourcing. In-house provision is often seen as the best way to provide an organization with IT services that are well adapted to support its business activities while preserving its trademark processes and know-how. On the other hand, critics argue that a better solution is to outsource those IT activities to specialists, thus permitting the company to focus on its core business. The choice of a sourcing mode has an impact on the ability of the firm to implement its systems and ultimately to compete in its field of business. In order to better understand under what conditions a firm should choose one sourcing mode over another, we argue that it is necessary to analyze the interactions between a firm's competencies and the strategic value of those competencies. This is investigated using evidence from 21 information system projects. The0501n findings were that the best predictor of success and failure, by far, is the fit between the governance mode and the position of the project in the value/availability matrix. Another interesting finding is that no sourcing mode per se seems to lead to successful outcomes. It is always a matter of selecting the appropriate mode for each situation. De plus en plus, les technologies de l'information sont au centre des préoccupations des gestionnaires. Elles commandent des investissements massifs et peuvent être gérées de diverses manières. Traditionnellement, une gestion interne était favorisée pour fournir à l'organisation des services sur mesure et pour protéger des pratiques uniques, permettant à l'organisation de se différencier. Les détracteurs de cette approche soutiennent que l'impartition est un meilleur choix. L'impartition permet à la firme de se concentrer sur ses compétences de bases tout en lui donnant accès à des spécialistes de pointe. Pour mieux comprendre le lien entre les compétences de la firme et l'impartition, 21 projets sont étudiés. Les résultats indiquent que le meilleur prédicteur de succès est l'adéquation entre le mode de gestion et le profil de compétences de la firme.Outsourcing of IT, resource-based theory, IT resources, Impartition, approche centrée sur les resources, étude de cas