Theses and Dissertations
2007
ABSTRACTS
Departamento de Informática
Pontifícia Universidade Católica do Rio de Janeiro - PUC-Rio
Rio de Janeiro - Brazil
This file contains the list of the MSc. Dissertations and PhD. Thesis presented to the Departmento de Informática, Pontifícia Universidade Católica do Janeiro - PUC-Rio, Brazil, in 2007. They are all available in print format and, according to the authors' preference, some of them are freely available for download, while others are freely available for download to the PUC-Rio community exclusively(*).
For any requests, questions, or suggestions, please contact:
Rosane Castilho
bib-di@inf.puc-rio.br
Last update: 10/MARCH/2008
[07_MSc_correia]
Adolfo Guilherme Silva CORREIA. Uma arquitetura baseada em agentes de software
para a automação de processos de gerência de falhas em redes de
telecomunicações. [Title in English:
A software agents based architecture for the automation of fault management
processes in telecommunications networks] M.Sc. Diss. Port. Presentation:
03/04/07 114 p. Advisor: Carlos José Pereira da Lucena.
Abstract:Abstract: The last few years have been marked by a significant and
worldwide growth in the demand for telecommunications services. Such scenery of
network expansion and the need for coexistence and interoperability of different
technologies in an economically viable way provides great challenges for the
management, operation and maintenance of telecommunications networks. This work
presents some of the main network management models and paradigms traditionally
employed in telecommunications networks and that still count with wide adoption
in the industry as of this day. Many of the presented models have been
significantly influenced by concepts and techniques originated in the software
engineering field. A great emphasis is particulary given to the use of network
management techniques based on software agents. To this end, important concepts
of software agents are presented, as well as examples of works where software
agents are used in the network management domain. Finally, an architecture based
on software agents used for fault management in legacy telecommunications
networks, which are usually managed by centralized systems, is proposed. The
main objective of this architecture is to allow the diagnosis and the correction
of network faults in a way not to overload the centralized management system. To
this end, the architecture uses software agents that distribute information
maintained in the centralized management system to other agents of the system.
In such way, it is possible for the agents responsible for executing the fault
diagnosis and correction procedures to perform their activities without the
necessity for direct communication with the centralized system.
[07_MSc_barros]
Alexandra Barreto Assad de BARROS. Finalizadores e ciclos em tabelas fracas. [Title in English:
Implementing finilazers using weak references] M.Sc. Diss. Port. Presentation:
13/04/07 75 p. Advisor: Roberto Ierusalimschy.
Abstract: Weak References and finalizers constitute an elegant alternative to
obtain control over the interaction between the application and the garbage
colector. However, in some context, finalizers are not necessary because it's
possible to extend the weak reference mechanism in order to give support to
finalization. In this work, we present a survey of the most common uses of these
mechanisms. We also show how weak references can replace finalizers proposing a
weak reference based implementation for each finalizer use. Based on this survey,
we developed a finalization mechanism based on weak references for the Lua
programming language. Motivated by our proposal of a better exploration of the
weak reference mechanism, we developed a solution for an important problem
related to cycles on weak tables, an structure created using weak references.
Cyclic references between keys and values prevent the elements inside the cycle
from being collected, even if they are no more reachable. This ends up bringing
difficulties to the use of weak tables in certain kinds of applications. The
Haskell programming languages solved this problem implementing an adaptation of
a mechanism called ephemerons. Based on this fact, we modified the Lua garbage
collector in order to offer support to ephemerons. As a result, we were able to
solve the problem of cycles on weak tables in Lua.
[07_MSc_cerqueira]
Ana Luiza Ávila CERQUEIRA. Integração de ontologia com modelagem de processo: um
método para facilitar a elicitação de requisitos.[Title in English:
Ontology integration from UDI to business process modeling: an approach to
facilitate requirements elicitation] M.Sc. Diss. Port. Presentation: 16/04/07 239 p. Advisor:
Julio Cesar Sampaio do Prado Leite.
Abstract: Requirements definition, where engineers interact with clients to
better know the organization's activities and understand their needs, is a key
process to the success of an information system. A such, requirements defined
with clarity and according to the client's needs are fundamental to the
development of effective information systems for the organization. This
dissertation proposes a method to help requirements engineers in the task of
eliciting requirements. These requirements must be in accordance with the
business as to improve the quality of the organization's information systems.
The proposed method integrates process modeling and business ontology. The work
assumes that the integration of these perspectives provodes a solid source of
organization knowledge. Using this knowledge source, requirements engineers are
empowered to define requirements that better fits the organizations business.
The integration of process modeling and business ontology is described in detail
and exemplified by a case study.
[07_MSc_fialho]
André Tadeu Santos FIALHO. Uso de animações em interfaces de aplicações
hipermídia. [Title in English: Use of animations in hypermedia application
interfaces] M.Sc. Diss. Port. Presentation: 30/07/07 133 p. Advisor: Daniel Schwabe
Abstract: In this dissertation we introduce an approach for the authoring of
animated transitions in Web applications. The transitions can be defined as
navigational state changes that result in the alteration of the presented
widgets and interface. These alterations are usually represented abruptly
through non-animated interfaces. The use of animation allows a gradual
representation of the transformations that occur, characterizing a smooth
transition that reveals to the user the underlying navigation operation. The
approach is divided in two steps: The interface modeling and the transition
modeling. In the first step, we define the interfaces through a specification of
abstract interfaces provided by the SHDM/OOHDM method. In the transition
modeling, we identify the animations for each transformation and define through
the animation rhetorics: The transition rhetorical structure, which defines the
animation execution sequence, and the rhetoric styles, that defines the effects
and duration proprieties of the animation. The approach was implemented by
extending the hypermedia authoring environment, HyperDE, providing smooth
transitions for the generated application prototypes. In order to allow the
execution of the animations, we have also developed a transition library using
Dynamic HTML technology. A preliminary evaluation with showed greater
satisfaction.
[07_MSc_figueiredo]
Aurélio Moraes FIGUEIREDO. Mapeamento automático de horizontes e falhas em dados
sísmicos 3D baseado no algoritmo de gás neural evolutivo. M.Sc. Diss. Port.
Presentation: 29/06/07 79 p. Advisor: Marcelo Gattass
Abstract: In this work we present a clusterization-based method to map seismic
horizons and faults from 3D seismic data. We describe a method used to quantize
an initial seismic volume using a trained instance of the Growing Neural Gas
(GNG) algorithm. To accomplish this task we create a training set where each
sample corresponds to an entry volume voxel, retaining its vertical neighboring
information. After the training procedure, the resulting graph is used to create
a quantized version of the original volume. In this quantized volume both
horizons and faults are more evidenced in the data, and we present a method that
uses the created volume to map seismic horizons, even when they are completely
disconnected by seismic faults. We also present another method that uses the
quantized
version of the volume to map the seismic faults. The horizon mapping procedure,
tested in different volume date, yields good results. The preliminary results
presented for the fault mapping procedure also yield good results, but needs
further testing.
[07_MSc_vinhosa]
Bernardo Arraes VINHOSA. Uma abordagem para a evolução transparente em
repositórios de medição de software: o sistema Clairvoyant. [Title in English:
An approach for transparent evolution in software measurement repositories: the
Clairvoyant system ] M.Sc. Diss. Port. Presentation:
23/03/07 109 p. Advisor: Arndt von Staa.
Abstract: Abstract: The Clairvoyant system is a software measurement repository
prototype which stands out for allowing transparent evolution in its measurement
model. This means that changes can be made to its measurement model without
revealing the underlying storage structure which makes possible this evolution.
This is an important concern due to the fact that the information needs to which
the measurements respond constantly evolve. The Clairvoyant system was designed
based on a measurement meta-model and a measurement query model to make it
possible to transparently evolve its measurement model. This work explains these
models and studies their influence on the repository's operational
macro-processes (measurement model maintenance, measurement data importing,
measurement data querying and measurement data exporting).
[07_PhD_laufer]
Carlos Cesar LAUFER. Contract oriented web services model (COWS) - um modelo
baseado em contratos para suporte a processos de negócios na web. [Title in English:
Contract Oriented Web Services Model (COWS) – a semantic contract support for
e-business processes] Ph.D. Thesis. Port. Presentation: 02/04/07 154 p.
Advisor: Daniel Schwabe.
Abstract: Business processes are established via relationships between partners
with a common goal. These relationships are specified in contracts, which could
be explicit or implicit, oral or written, and so on. When a person searches for
a business partner, she is looking for a partner that can fulfill a relationship
specified in a contract. To support such processes in the Internet (and in the
Web) it is necessary to characterize all of its aspects, such as agents,
contracts, roles, relationships, interactions between partners, policies, etc.
This dissertation presents the Contract Oriented Web Services Model (COWS) - a
model for an appropriate environment for E-Business dialogues, implemented using
Web Services. COWS is based on well-defined contracts agreed upon by all
concerned parties and incorporates various levels of applicable policies. These
policies can be related to payment methods, quality of services (QoS), privacy
policies, rights, products return, trust, etc. Contracts may refer to other
contracts and are valid whitin forae, which have default global policies. A
prototype web environment supporting COWS has been implemented to test the
concepts that extend the discovery process. All COWS models have been specified
an ontologies, using Flora-2.
[07_MSc_batista]
Carlos Freud Alves BATISTA. Métricas de segurança de software.
[Title in English:
Software security metrics] M.Sc. Diss. Port. Presentation: 16/04/07 102 p. Advisor:
Arndt von Staa.
Abstract: Today's growing dependency on information technology (IT) makes
software security a key element of IT services. In recent years public and
private institutions raised the investment on information security, however
the number of attacks is growing faster than our power to face them, putting at
risk intellectual property, customer's confidence and businesses that rely on IT
services. Experts say that most information security incidents occur due
to the vulnerabilities that exist in software systems in first place. Security
metrics are essential to assess software dependability with respect to security,
and also to understand and manage impacts of security initiatives in
organizations. However, security metrics are shrouded in mystery and very hard
to implement. This work intends to show that there are no adequate metrics
capable of indicating the security level that a software will achieve. Hence, we
need other practices to assess the security of software while developing it and
before deploying it.
[07_MSc_sousa]
Daniel Xavier de SOUSA. Estratégias de balanceamento de carga para avaliação
paralela do BLAST com bases de dados replicadas e fragmentos primários. [Title in English:
Workload balancing strategies for parallel BLAST evaluation on replicated
databases and primary fragments] M.Sc. Diss.
Port. Presentation: 27/07/07 84 p. Advisor:
Sérgio Lifschitz.
Abstract: A fundamental task in the area of computational biology is the searh
for relevant information within the large amount of available data. Among others,
it is important to run tools such as BLAST - Basic Local Alignment Search Tool -
efficiently, which enables the comparison of biological sequences and discovery
of homologies and other related information. However, the execution cost of
BLAST is highly dependent on the database size, which has considerably increased.
The evaluation of BLAST in distributed and parallel environments like PC
clusters has been largely investigated in order to obtain better performances.
This work reports a replicated allocation of the (sequences) database where each
copy is also physically fragmented, with some fragments assigned as primary.
This away we show that it is possible to execute BLAST with some nice
characteristics of both replicated and fragmented conventional strategies, like
flexibility and I/O parallelism. We propose two dynamic workload balancing
strategies associated with this data allocation. We have adopted a non-intrusive
approach, i.e., the BLAST code remains unchanged. These methods are implemented
and practical results show that we achieve not only a balanced workload but also
very good performances.
[07_MSc_santos]
Daniele Reis Gonzaga SANTOS. Suporte ao registro e uso de decisões de projeto de
aplicações para a Web. [Title in English:
Support for recording and using design rationale for Web application design]
M.Sc. Diss. Port. Presentation: 13/04/07 115 p. Advisor: Daniel Schwabe.
Abstract: Every designer follows some line of reasoning, and makes
several decisions when designing an artifact, which is the final result of this
decision process. This design reasoning and decision structure, commonly called
Design Rationale, is rarely captured and recorded. The reasons for this seem to
be due to the lack of appropriate tools, which should capture the Design
Rationale in an unobtrusive way, allowing the designer to focus on the design
itself. Such tools should also allow reusing previous design solutions, helping
the designer/developer to improve the quality of the solution. The goal of
this dissertation is to provide means to capture, record and use Design
rationale within a prototyping environment for hypermedia applications. As
result, we present the HyperDE+DR environment, which combines the HyperDE
environment with the Kuaba approach for recording Design Rationale. The HyperDE+DR
environment automatically generates and records design decisions made by the
designer during the development process. Questions and ideas are automatically
generated and tentatively answered, to be reviewed later by the designer
by following the OOHDM and SHDM design methods that underlie the original
HyperDE environment. In addition, HyperDE+DR supports Design Rationale use, by
allowing integration of previous design rationales into a design being
developed. This allows improving the completeness and consistency of the
resulting design, also lowering development costs.
[07_MSc_carvalho]
Darlinton Barbosa Feres CARVALHO. Um framework para construção de vocabulário e
sua aplicação ao problema de seqüenciamento de carros. [Title in English:
A framework for vocabulary building and its application to the car sequencing
problem] M.Sc. Diss. Port. Presentation: 19/03/07 100 p. Advisors:
Carlos José Pereira de Lucena e Celso da Cruz Carneiro Ribeiro.
Abstract: Vocabulary building is a heuristic for solving combinatorial
optimzation prolems, based on the identification of solution fragments which are
common to good solutions and on their combination to intensify the search on
promising regions of the solution space. This technique can be vastly applied on
problem solving. The technology of framework is an efficient strategy to
facilitate the implementation and comparison of same domain algorithms. The
objective of this work is to develop a framework for the implementation of
heuristics based on vocabulary building. Its development was based on a wide
bibliographic revision about the technique and good software engineering
practices, like oriented objects frameworks and design patters. We generated
applications of the framework to solve the car sequencing problem, which is a
combinatorial problem proposed by real requirements of the industry.
[07_PhD_vasconcelos]
Davi Romero de VASCONCELOS. Lógica modal de primeira-ordem para raciocinar sobre
jogos. [Title in English:
First-order modal logic for reasoning about games] Ph.D. Thesis. Port. Presentation:
12/04/07 241 p. Advisor: Edward Hermann Haeusler.
Abstract: Games are abstract models of decision-making in
which decision-makers (players) interact in a shared environment to accomplish
their goals. Several models have been proposed to analyze a wide variety of
applications in many disciplines such as mathematics, computer science and even
political and social sciences among others. In this work, we focus on Game
Theory and Game Logics. We present a first-order modal logic based on CTL,
namely Game Analysis Logic (GAL), to model and reason about games. The standard
models of Game Theory (strategic games, extensive games and coalition games) as
well as their solution concepts (Nash equilibrium, subgame perfect equilibrium
and core), respectively, are express as models of GAL and formulas of GAL.
Moreover, we study the
alternatives of De Re and De Dicto quantification in the context of extensive
games. We also show that two of the most representative game logics, namely
Alternating-time Temporal Logic (ATL) and Coalitional Game Logic (CGL), are
fragments of GAL. We also characterize a class of multi-agent systems, which is
based on the architecture Belief-Desire-Intention (BDI), for which there is a
somehow equivalent class of games and vice-versa. As a consequence, criteria of
rationality for agents can be directly applied to players vice-versa. Game
analysis formal tools can be applied to MAS as well. From a practical point of
view, we provide and develop a model-checker for GAL.
In addition, we perform case studies using our prototype.
[07_MSc_nakamura]
Fábio Issao NAKAMURA. Animação interativa de fluido baseada em partículas pelo
método SPH. [Title in English: Fluid animation based on particles systems] M.Sc. Diss. Port. Presentation:
30/03/07 64 p. Advisor: Waldemar Celes Filho.
Abstract: This work investigates the use of particle-based system for fluid
animation. Based on proposals presented by Muller et al., the goal of this
dissertation is to investigate and fully understand the use of a Langrangian
method known as Smoothed Particle Hydrodynamics (SPH) for fluid simulations. A
library has been implemented in order to validate the method for fluid animation
at interactive rate. To demonstrate the method effectiveness and efficiency, the
resulting library allows the instantiation of different configurations,
including the treatment of fluid-obstacle collisions, interaction between two
distinct fluids, and fluid-user interaction.
[07_MSc_augusto]
Fernanda Duran de Moura AUGUSTO. Um mecanismo de governança para sistemas
multi-agentes abertos baseado em testemunhos. [Title in English: A governance
mechanism for open multi-agent systems based on testimonies] M.Sc. Diss. Port. Presentation:
04/04/07 96 p. Advisors: Carlos José Pereira de Lucena e Viviane Torres
da Silva.
Abstract: Governance copes with the heterogeneity, autonomy and diversity of
interests among different agents in a multi-agent system (MAS) by establishing a
set norms. Most of the governance enforcement mechanisms usually check norm
violations from the point of view of interaction protocols. However, in MAS,
with the presence of heterogeneous and independently designed agents, there will
be private messages, that will only be perceived by their senders and receivers,
and execution of actions that will only be observed by the agents that execute
them or by agents that suffers from their consequences. This work presents a
governance mechanism for MAS based on testimonies. Agents can witness facts that
are related to norm violations witch they are aware of. The proposed mechanism
is composed by three sub-systems: reputation, judgment and sanction. This work
focuses only in the judgment sub-system, witch is responsible for receiving
testimonies and proving a decision, pointing out if an agent has really violated
a norm. The judgment sub-system architecture and a generic judgment process will
be presented. Finally, the use of this mechanism will be exemplified by a case
study.
[07_MSc_mano]
Fernando Rimola da Cruz MANO.
Classificação e segmentação de áudio a partir de
fatores de escala MPEG. [Title in English: Using
scale factors for segmentation and classification of MPEG audio] M.Sc. Diss.
Port. Presentation: 03/09/07 62 p. Advisor: Bruno Feijó.
Abstract: With the growth of production and storing of digital media, audio
segmentation and classification are becoming increasingly important. This work
is based on characteristics of the MPEG standard, considered to be the standard
for digital media storage and retrieval, to propose efficient algorithms to
perform these tasks. While there are many studies based on video analysis, the
audio information is still not widely used in an efficient way. The suggested
algorithms for both tasks are based only on the scale factors present on layer 2
MPEG audio. That allows them to read the smallest amount of information possible,
significantly diminishing the amount of data manipulated during the analysis and
making their performance excellent in terms of processing time. The algorithm
proposed for audio classification divides audio in four possible types: silent,
speech, music and applause. The segmentation algorithm finds significant changes
on the audio signal that represent clues of audio segments and scene changes.
Tests were made with a wide range of types of video, and both algorithms show
good results.
[07_MSc_saramago]
Filipe Ancelmo SARAMAGO. Representações para modelagem computacional da
discussão estruturada em rede: um estudo de caso com a ferramenta de fórum do
ambiente Aulanet. [Title in English: Computational support for net structured
discussion: a case study with the AulaNet environment forum tool] M.Sc. Diss. Port. Presentation:
29/03/07 76 p. Advisor: Hugo Fuks.
Abstract: This works presents an investigation regarding the computational
support for net structured forum discussions. In forums, the discussion is
usually structured on a tree format through hierarchically connected messages.
The use of a more complex structure than a tree indicates some difficulties for
the participants. It is more difficult to read, due to the lack of a linear
structure and to write, due to the possibility of more flexible associations
among messages. The hypothesis being investigated is that, given a specific
computational support, the participants of a forum will have an adequate
participation in the net structured discussion; an adequate participation
happens when a participant can understand the associations among messages (reading
process) or when a new message is posted with associations in the discussion (writing
process). The proposed solution was the usage of a multiple reference mechanism
and the visualization and the way to build the forum net structure; these tools
were implemented on the Conference Service of AulaNet environment. To
investigate the proposed solution some forum sessions with Computer Science
graduate and pos-graduate students were conducted. In these sessions, the forum
discussion structure, its visualization and the way the discussion was built
were varied with the aim at analyzing the influence of the student participation.
From the case study conducted it was concluded that, despite the identified
difficulties, the participants managed to follow the discussion and posted
messages with associations, which indicates the viability of net structured
forums. Other conclusion was that the training with graphical tools to generate
the net structured discussion is useful to eliminate some of the difficulties
that is present on the more complex structured discussion.
[07_MSc_anjos]
Flavia Medeiros dos ANJOS. Reorganização e compressão de dados sísmicos [Title in English:
Re-organization and compression of seismic data] M.Sc.
Diss. Port. Presentation: 09/08/07 78 p. Advisor: Eduardo Sany Laber.
Abstract: Seismic data, used mainly in the petroleum industry, commonly present
sizes of tens of gigabyte, and, in some cases, hundreds. This work presents
propositions for manipulating these data in order to help overcoming the
problems that application for seismic processing and interpretation face while
dealing with file of such magnitude. The propositions are based on
re-organization and compression. The knowledge of the format in which the data
will be used allows us to restructure storage reducing disc-memory transference
time up to 90%. Compression is used to save storage space. For data of such
nature, best results in terms of compression rates come from techniques
associated to information loss, being clustering one of them. In this work we
present an algorithm for minimizing
the cost of clutering a set of data for a pre-determined number of clusters.
Seismic data have space coherence that can be used to improve their compression.
Combining clustering with the use of space coherence we were able to compress
sets of data with rates from 7% to 25% depending on the error associated. A new
file format is proposed using re-organization and compression together.
[07_MSc_oliveira]
Glória Maria de Paula OLIVEIRA.
Aplicação da análise de sistemas à definição de
processos de desenvolvimento de software [Title in English: Using software
engineering concepts to define software development processes]
M.Sc. Diss. Port. Presentation: 24/08/07 92 p. Advisor:
Arndt von Staa.
Abstract: Software quality depends heavily
on the quality of the process used to develop it. In order to assist the
definition of an adequate process, there are several process models, maturity
models and quality standards. However, creating or improving a software
development process may be tough due to the large amount of available
information and decisions that have to be made. Another central problem is the
risk of defining an ineffective process, that is, one that increases the
bureaucracy but doesn’t improve the quality of the systems developed with its
support. This dissertation presents an approach for defining software
development processes based on the concepts of system analysis, based on the
analogy between software and process elaboration. One of the most important
attributes of this approach is the focus on Risk Management, considering the
identified risks in the process definition as well the possible risks during
software process execution.
[07_MSc_hazan]
Guilherme Campos HAZAN. Uma especificação de máquina de registradores para Java.
M.Sc. Diss. Port. Presentation: 09/04/07 72 p. Advisor: Roberto Ierusalimschy
Abstract: The Java language was created with a focus on portability. The code
generated by the compiler is interpreted by a virtual machine, and not directly
by the target processor, like programs written in C. This intermediate code,
also known as bytecode, is the key to Java's portability. The Java Bytecodes use
a stack to manipulate the instruction operands. The use of stack has their
pros and cons. Among the advantages, we can cite the simplicity of
implementation of the compiler and virtual machine. On the other hand, there is
a speed reduction in the program's execution, due to the need to move the
operands to and from the stack, and retrive results from it, increasing the
number of instructions that are processed. Much study has been done
indicating that register-based virtual machines can be faster than the ones
based on stacks. Based on this, we decided to create a new bytecode
specification, proper for a virtual machine based on registers. By doing so,
we hope to obtain an increase in an application's performance.
[07_MSc_santos]
Guilherme Nascimento Pate SANTOS. Introduzindo variabilidade no desenvolvimento
de sistemas multi-agentes. [Title in English: Introducing a variability into
development of multi-agent systems] M.Sc. Diss. Port. Presentation: 22/03/07 110 p. Advisors:
Carlos José Pereira de Lucena and Ricardo Choren Noya.
Abstract: The current agents' modeling languages aim at representing the system
and theirs agents in a clear way by diagrams, which permit shows theirs goals,
plans and actions. Even with all provided by the language, some systems can't be
represented a correct from yet, because the current agents' modeling languages
represent only a whole system and not a product line. In this way the method
proposed tries to determine a mapping of the flexibility points into software
agents. The flexibility points into agents are defined to theirs plans and
actions. Such points can be flexible if show a variability characteristic. The
variability is presented by two points of view: the variability of plans and
variability of action, where the variability of plans can enable many distinct
plan for an agent, in other words, accept distinct applications for each one of
their plans; and the variability of actions that enable the actions are executed
in distinct form that result in distinct applications. With that, we can see an
abstract actions and abstract plans will be inherited by the concrete actions
and concrete plans, and that in the future will define new applications. For
this the method uses the diagrams, tags and documentation. The documentation is
used like a guide in a plan instance and action instance. After, these agents
can generate the instance of new applications by yours owner plans and actions
that's determine the software product line and consequently it is possible to
use the framework idea. With this approach it is possible to intoduce into agent
world all the advantage of frameworks and product lines, techniques that are
traditionally used in object orientation. Moreover, the approach can be used
concomitantly with current' modeling languages. The benefits of the approach
will be shown in more details through a case study.
[07_MSc_wagner]
Gustavo Nunes WAGNER. Visualização interativa de
modelos massivos de engenharia na indústria de petróleo com o algoritmo de
Voxels distante. [Title in English: Interactive visualization of massive
engineering models in the Oil & Gas industry using the FarVoxels algorithm] M.Sc. Diss. Port. Presentation:
09/04/07 88 p. Advisors: Marcelo Gattass and Alberto Barbosa Raposo.
Abstract: Current projects of Offshore Structures require virtual
prototyping of huge CAD models. These models usually have hundreds of millions
of triangles and for this reason they cannot be sent directly to current
graphical boards that can render interactively only a few millions of triangles.
There are many different approaches to deal with this problem including a new
impostor strategy based on Voxel visualization. This strategy is promising
because it deals well with level of detail, occlusion and out of core model
storage. This dissertation presents a variant of the Far Voxels algorithm. This
variant is implemented and tested against typical CAD models. Finally, from
these tests, the dissertation present some conclusions and suggestions for
future work.
[07_PhD_carvalho]
Gustavo Robichez de CARVALHO. G-Frameworks: uma abordagem para a reutilização de
leis de interação em sistemas multiagentes abertos. Ph.D. Thesis. Port.
Presentation: 14/05/07 186 p. Advisor: Carlos José Pereira de Lucena.
Abstract: One of the challenges of software development is to produce
applications that are designed to evolve, reducing maintenance efforts. Many
techniques developed to govern the interaction laws in open multi-agent systems
were proposed, but the flexibility and reuse concerns of interaction laws were
not systemically fulfilled by them. The technology of g-frameworks intends to
guide the design and the implementation of interaction laws in open multi-agent
systems, aiming to facilitate the production of interaction law governance
mechanisms. The flexibility in g-frameworks is achieved by specific increments
that the instances under development require, to complete and adapt the original
functionalities of the g-framework. The reuse in g-frameworks is related to a
common design and codification of that interaction laws that are shared by
instances developed with the g-framework. The benefits of this approache might
positively impact the development of software considering the costs and the
necesary time to construct the family of governance mechanisms of multi-agent
systems. In this thesis, some techniques to promote reuse of interaction laws
were propose to fulfill this goal. One method to orient the development of
g-frameworks is proposed. Experiments were developed and they are described in
this thesis.
[07_PhD_rubinsztejn]
Hana Karina Salles RUBINSZTEJN. Suporte à adaptação de conteúdo sensível a
contexto para dispositivos móveis em sistemas publish/subscribe.
[Title in English: Context aware content adaptation for
mobile clients in publish/subscribe systems] Ph.D. Thesis. Port.
Presentation: 14/09/07 180 p. Advisor: Markus Endler.
Abstract: Services for information dissemination ("push" services) are being
widely used, in particular for applications involving mobile users. These
services generally serve devices with different resources and with distinc
execution contexts (wireless connectivity, energy source, etc.) making it
necesary to adapt disseminated content individual and dynamically for each
client. Since many content adaptations involve costly operations and demand
high processing power, these should not be executed at the mobile clients. On
the other hand, it is neither efficient nor scalable to execute the adaptations
for each mobile client at the server. Thus, in such services, it is common to
use proxies dedicated to content adaptations (based on the context) of clients.
Asynchronous communication, such as publish/subscribe, is considered the most
appropriate form of communication for this type of service. On the other hand,
systems for context-aware content adaptation do not support this type of
communication. In this thesis we present an architecture for publish/subscribe
systems with context-aware content adaptation, that uses an algorithm that
optimizes the content adaptation for large sets of clients..
[07_MSc_prange]
Henrique Feliciano PRANGE. Uma avaliação empírica de um ambiente favorável para
o desenvolvimento dirigido por testes. [Title in English: An empirical
evaluation of an environment designed for test driven development] M.Sc. Diss. Port. Presentation:
21/03/07 117 p. Advisor: Arndt von Staa.
Abstract: Test Driven Development (TDD) is one of the eXtreme Programming's (XP)
easiest practices to understand but at the same time difficult to implement. It
is necessary to use complementary practices, appropriate tools, and follow
carefully some rules for achieving good results. A real experiment creating an
adequate environment for TDD was conducted in a small company. This study will
show the results obtained. What are the advantages and disadvantages of each one
of the practices? How to establish these practices in small company daily
operations? What type of environments has to be built? Which tools? How much
time and investment for implementing this kind of enhancement would be required?
This work will present answers to these questions.
[07_MSc_cunha]
Herbet de Souza CUNHA. Uso de estratégias orientadas a metas para modelagem de
requisitos de segurança. [Title in English: The use of goal-oriented strategies
to security requirements modeling] M.Sc. Diss. Port. Presentation: 16/03/07 148 p. Advisor:
Julio Cesar Sampaio do Prado Leite.
Abstract: Adding security requirements to software architectures after they are
built is a hard work. Security concepts have to cross the whole software
development cycle, from requirement engineering to deployment, passing by
design, coding and test. This work presents an approach to security requirements
modeling, mainly the information confidentiality and consistency, based on goal
oriented strategies, bringing the security issues to the beginning of the
software development cycle. It also present the results of this approach in a
case study.
[07_MSc_venetillo]
Jerônimo Silvério VENETILLO. Simulação de partículas baseada em GPU com
tratamento de colisão. [Title in English: GPU-based particle simulation with
collision handling] M.Sc. Diss. Port. Presentation: 26/03/07 47 p. Advisor:
Waldemar Celes Filho.
Abstract: This work presents a new proposal for the implementation of a
GPU-based particle system. The simulation runs entirely on the graphic processor,
thus eliminating data transfer between the CPU and the GPU. The proposed system
is able to simulate particles with different diameters in confined environments,
including support for inter-particle collisions, constraints, and
particle-obstacle collisions. Inter-particle collision detection is accomplished
by subdividing the space into a regular grid of cells. On modern graphics cards,
the system is able to simulate up to one million particles at interactive rate.
It is also proposed a flexible approach for modeling the obstacles that define
the environment, allowing the creation of different scenes without relying on
shader re-coding. The system is divided in different shaders responsible for
each stage of the smulation. One fragment program is responsible to advance the
particles in time. After that a vertex program builds the space subdivision
structure. The following stages (collision detection and response, and
constraint solving) are performed only by fragment programs using the relaxation
method.
[07_MSc_guedes]
José de Souza Pinto GUEDES. Um framework para o cálculo de reputações de
agentes de software baseado em testemunhos. [Title in English: A framework for
the evaluation of software agents reputation based on testimonies] M.Sc. Diss. Port. Presentation:
28/03/07 117 p. Advisors: Carlos José Pereira de Lucena and Viviane
Torres da Silva.
Abstract: Abstract: Reputation mechanisms are being used to
increase the reliability and performance of virtual societies. Different
decentralized reputaion models have been proposed based on interactions among
agents. Each system evaluates and stores the reputations of the agents
with whom they have interacted and can also testify to other agents about such
reputations. The main disadvantages of such approaches when applied to open
large-scale multi-agent systems are the difficulty of establishing strong links
between the agents, the sometimes infeasible witness search process, the fact of
the reputation is being influenced by the point of view of another agent and the
fact the agents cannot be willing to testify and collaborate with possible
competitive agents. In this work we propose a hybrid reputation system with
centralized and decentralized characteristics to overcome such problems. The
reputations are provide by the system agents themselves but also by centralized
subsystems that can be easily reached by any agent and can supply reliable
reputations of any agent based on testimonies about undesired agent's behavior,
characterized by the violation of system norms. Such centralized subsystems are
instances of the proposed framework.
[07_PhD_imperial]
Juliana Carpes IMPERIAL. Confiança em agentes inteligentes [Title in English:
Trust in intelligent agents] Ph.D. Thesis. Port.
Presentation: 10/08/07 136 p. Advisor: Edward Hermann Haeusler
Abstract: Trust is a fundamental concern in large-escale open distributed sytems.
It lies at the core of all interactios between the entities that have to operate
in such uncertain and constantly changing environmonts. Given the complexity of
the interactions, these components, and the ensuing system, are increasingly
being conceptualised, desined, and built using agent-based techiques. Therefore,
the presence of trust is imperative in a multi-agent system (MAS). Consequently,
this work studies how to have a explicit trust model in intelligent agent, which
has beliefs, desires and intentions (BDI agent). Thas is, the agent now has a
fourth component called Trust. This way, a logic to include the concept of trust
in an open BDI MAS is interesting, so that the different aspects of a trust
model can be expressed formally and accuratelly. This is achieved by using an
indexed multi-modal logic, where the possible worlds which model a multi-agent
system represent which agents are in the system in a given moment. Moreover, for
each one of the three original components of a BDI agent, where the components
represent beliefs, desires and intentions, there is a representation of possible
worlds, because these are treated as modalities. However, trust is modelled as
predicate, not as a modality.
[07_MSc_salgado]
Luciana Cardoso de Castro SALGADO. CommEST - uma ferramenta de apoio ao método
de avaliação de comunicabilidade [Title in English: CommEST - a communicability
evaluation support tool] M.Sc. Diss. Port. Presentation: 28/03/07 221 p. Advisor:
Clarisse Sieckenius de Souza.
Abstract: Abstract: With increasing competition among software producers and
free distribution of software over the Internet, there is a growing concern with
developing high-quality software, which can actually improve people's lives and
allow for pleasant and productive use experience. To this end, one of the
industry's needs is the availability of methods and techniques for evaluating
use experience. Some computer tools have been developed to support the
application of existing evaluation methods. Among them, some are commercial,
others have been developed in universities, in non-governmental organizations,
and some have even been developed by government agencies. The focus of this work
is on the communicability evaluation method, an epistemic tool proposed by
Semiotic Engineering, a semiotic theory of human-computer interaction. The
method consists of a systematic procedure for evaluating the user' experience as
they interact with systems, emphasizing the communicative aspects of the process.
Although it is taught in a considerable number of graduate and undergraduate
schools of Informatics in Brazil, the method is not sufficiently utilized to
either generate new knowledge for human-computer interaction research, or
consolidate itself as a tool for extensive professional practice. This is the
consequence of difficulties in learning and teaching the method. Therefore, this
work presents a computer tool to support the application of the communicability
evaluation method, specifically designed to facilitate the teaching and learning
of the method.
[07_PhD_lima]
Luciana dos Santos LIMA. Um protocolo para descoberta e seleção de recursos em
grades móveis ad hoc. [Title in English: A protocol for resource
discovery and selection in mobile ad hoc grids] Ph.D. Thesis. Port. Presentation:
15/06/07 213 p. Advisors: Markus Endler, Luiz Fernando Gomes Soares,
Antônio Tadeu de Azevedo Gomes, Artur Ziviani.
Abstract: In the last few years, the use of mobile devices in computational
grids has seen a growing interest. Nevertheless, a more challenging issue, the
dynamic establishment of mobile grids on wireless ad hoc netwoks, has been so
far only partially addressed. The first contribution of this thesis is the
proposal of a software architecture for mobile grids that can be used for both
infrastructured and ad hoc wireless networks. In the execution of conventional
applications in grids, the responsibility to provide the service is shared among
the most resourceful mobile devices. In mobile grids, it is fundamental that
resource discovery and selection of resources are jointly handled. This calls
for a mechanism that promotes the automatic selection of the best resource
provides amongst the discovered nodes, taking into account the requirements of
the application. Discovery and selection, however, have been traditionally
handled separately and in most approaches the selection of resources and
services requires explicit intervention by the user of the mobile grid. As a
second contribution of this thesis, we propose a protocol that integrates the
phases of resource discovery and automatic selection in mobile grids, allowing
that computational resource provisioning is scheduled among the most resourceful
nodes. Due to the dynamics of the resources needed in a mobile grid (for example,
free CPU time and available memory), the protocol is based solely on
demand-driven broadcasts. However, mainly in multihop ad hoc wireless networks,
this strategy can inccur in overhead at the involved devices, due to the
diffusion of requests and replies. A third contribution of this thesis is the
development of a mechanism that allows to reduce this overhead by means of the
suppression of redundant replies in the network. The mechanism has been
implemented in the context of the proposal protocol, but can be applied as well
to other query-based discovery protocols based on broadcasts. The experimental
results obtained from executions in a testbed and through simulations show that
the proposed protocol provides efficient load balancing between devices with an
increasing number of requests. Moreover, it can be observed that the mechanism
for suppression of replies scales well with respect to an increasing number of
devices when compared to other discovery protocols in wireless ad hoc networks
that are purely based on requests via broadcast.
[07_PhD_paula]
Maíra Greco de PAULA. ComunIHC-ES: ferramenta de apoio à comunicação entre
profissionais de IHC e engenheiros de software [Title in English: ComunIHC-ES:
an HCI tool to support the communication between HCI professionals and software
engineers] Ph.D. Thesis. Port. Presentation:
15/06/07 170 p. Advisor; Simone Diniz Junqueira Barbosa
Abstract: Developing interactive systems involves professionals from many areas
of expertise, includes HCI (Human-Computer Interaction) and Software Engineering
(SE), each one with specific focus and goals. HCI focuses, generally, on
understanding the user' characteristics, needs and objectives, their work
environment and the task they need or want to perform using the system. Based on
this understanding, HCI designs interface and interaction, constantly evaluating
the produced artifacts. SE, on the other hand, aims primarily at specifying,
implementing and testing the
interactive system's functionalities and architecture. These two areas have a
common objective: to create an interactive system that meets the needs of its
users. To attain this goal, this work supposes that, throughout the development
process, communication is needed between the professionals from these areas, in
order to create a shared understanding about the problem and about what should
be built, so that, consequently, the developed application layer will
becompatible with the interaction layer, promoting the consistency of what will
be presented to the end user. Thus, to support both the communication and the
negotiation about interaction design between HCI and SE professionals, this
research proposes a communication tool based on semiotic engineering, called
ComunIHC-ES. This tool contains information about the problem domain, its users,
the task involved and the usage context; a language to represent the interaction;
and elements that help to explain the HCI design to software engineers.
ComunIHC-SE was used in a case study involving professionals from both areas and,
after analyzing ist results, indications were obtained of its usefulness in
supporting both the HCI-SE communication and the software engineering' work.
[07_MSc_malcher]
Marcelo Andrade da Gama MALCHER. Um middleware e
aplicativo para apresentação colaborativa sensível a contexto em dispositivos
móveis [Title in English: A middleware and an application for context-aware,
collaborative presentation sharing on handhelds] M.Sc. Diss. Port.
Presentation: 24/08/07 109 p. Advisor: Markus Endler.
Abstract: The ongoing improvement of portable devices and the increasing
ubiquity of wireless networks enable the development of services and
applications for any-place-any-time collaboration among mobile users in many
different
environments, such as at home, in public areas, in universities, in companies,
among others. It is expected that the use of portable, wireless-enabled devices
in classrooms improves the interaction and engagement in the learning process.
This work describes a distributed application named iPH (Interactive Presenter
for Handhelds) that supports the sharing and co-edition of presentations among
an instructor and students of a classroom, as well as the middleware components
used for the development of iPH. This system can be executed on a wide range of
devices,
such as tablets, notebooks and handhelds (palmtops or smartphones), and uses the
device's context information to adapt itself to improve, for example, the
interaction with the user.
[07_MSc_fernandez]
Marcelo Gonella FERNANDEZ. Tratamento e compressão baseada em wavelets para
dados adquiridos por sensores. [Title in English:
Treatment and wavelet-based compression for sensor data]
M.Sc. Diss. Port. Presentation: 13/09/07 87 p. Advisor: Marco Antonio Casanova.
Abstract: This dissertation introduces a strategy to develop a compression
method for sensor data inspired on the JPG2000 techniques. The strategy adopted
processes data streams much in the same way as signal processing. Due to the
unstable nature of sensor data, noise is added to the original signal. This
noise is detected and treated while the signal is cleaned and smoothed, making
it easier to analyze the data stream. Less relevant signal components are
removed or approximated allowing the signal to be compressed with few
information loss.
[07_PhD_sayao]
Miriam SAYÃO. Verificação e validação em requisitos: processamento da linguagem
natural e agentes. [Title in English: Requirements verification and validation:
natural language processing and software agents] Ph.D. Thesis. Port. Presentation:
18/04/07 205 p. Advisor: Julio Cesar Sampaio do Prado Leite.
Abstract: In software development process, initial activities can involve
requirements elicitacion, modeling and analysis (verification and validation).
The use of natural language in the register of the requirements facilitates
the communication among stakeholders, besides offering possibilities to
customers and users to validate requirements without extra knowledge. On the
other hand, in the current global economy, software development for teams
geographically distributed is becoming a rule. In this scenario, requirements
verification and validation for medium or high complexity software can involve
the treatment of hundreds or even thousand requirements. With this complexity
order it is important to provide computational support for the software engineer
execute quality activities. In this work we propose a strategy which combines
natural language processing (NLP) techniques and software agents to support
analysis activities. We have generated textual or graphical visions from groups
of related requirements; visions help completeness analysis, identification of
duplicities and dependences among requirements. We use content analysis
techniques to support the identification of omissions in nonfuctional
requirements. Also, we propose a strategy to construct the lexicon, using NLP
techniques. We use software agents to implement web services that incorporate
the related strategies, and also agents to act as personal assistants for
stakeholders of the software project.
[07_MSc_shaham]
Noam SHAHAM. Métodos para aceleração do ”non-local means” algoritmo de redução
de ruído. [Title in English: Methods for the acceleration of non-local means
noise reduction algorithm] M.Sc. Diss. Port. Presentation: 28/02/07 89 p. Advisor:
Eduardo Sany Laber.
Abstract: Non Local Means is an innovative noise reduction algorithm for images.It performs remarkably better than older generation algorithms but has a performance penalty that prevents it from being used in maintream consumer application. The objective of this work is to find ways of reducing the time-complexity of the algorithm and enabling its use in main stream image processing applications such as home photography or photo printing centers.
[07_PhD_lucena_rodrigues]
Paula Salgado LUCENA RODRIGUES. Um sistema de geração de expressões faciais
dinâmicas em animações faciais 3D com processamento de fala. [Title in English:
A System for generating dynamic facial expressions in 3D facial animation with
speech processing] Ph.D. Thesis. Port. Presentation:
20/12/07 161 p. Advisor: Bruno Feijó and Luiz Carlos Pacheco R. Velho.
Abstract: This thesis presents a system for generating dynamic facial
expressions synchronized with speech, rendered using a tridimensional realistic
face. Dynamic facial expressions are those temporal-based facial expressions
semantically related with emotions, speech and affective inputs that can modify
a facial animation
behavior. The thesis defines an emotion model for speech virtual actors, named
VeeM (Virtual emotion-to-expression Model), which is based on a revision of the
emotional wheel of Plutchik model. The VeeM introduces the emotional hypercube
concept in the R4 canonical space to combine pure emotions and create new
derived emotions. In order to validate VeeM, it has been developed an authoring
and player facial animation tool, named DynaFeX (Dynamic Facial eXpression),
where a speech processing is realized to allow the phenome and viseme
synchronization. The tool
allows either the definition and refinement of emotions for each frame, or group
of frames, as the facial animation adition using a high-level approach based on
animation scripts. The tool player controls the animation presentation
synchronizing the speech and emotional features with the virtual character
performance. DynaFeX is built over a tridimansional polygonal mesh, compliant
with MPEG-4 facial animation standard, what favors tool interoperability with
other facial animation systems.
[07_MSc_espinha]
Rafael de Souza Lima ESPINHA. Uma abordagem para a avaliação de processos
de desenvolvimento de software baseada em risco e conformidade.
[Title in English: An approach for the evaluation of software development
processes based on risk and compliance] M.Sc. Diss. Port. Presentation:
27/03/07 132 p. Advisors: Arndt von Staa and Carlos José Pereira de
Lucena.
Abstract: Nowadays, one of the main requirements of a software development
project is the delivery of a quality product that conforms to the expected
schedule and budget and satisfies customer needs. Using the hypothesis that the
quality of the developed is closely related to the processes used in its
development, many organizations invest in process improvement programs, where
the processes are continuously assessed and improved. In this work we propose an
approach for process assessment based on risk and process compliance analysis.
This approach is composed of a two-step appraisal method and a supporting tool.
In the first step of the method, a quick analysis is executed to identify the
most problematic areas. In the second one, a more elaborated analysis is
performed only in the critical areas, reducing the costs and increasing the
effectiveness of the appraisal. The tool uses a mechanism of surveys and
checklists to verify the risk and the compliance of the process of the
organization. A knowledge base is organized in accordance to a reference quality
norm or maturity model. At ther end of an assessment, reports, tables and charts
support the decision-taking, and they can be used to guide an improvement
program. The approach has been used in three case studies.
[07_MSc_rodrigues]
Rafael Ferreira RODRIGUES. Ambiente declarativo para sistemas que implementem o
GEM. [Title in English: Declarative environment for GEM Globally Executable MHP)-based
systems] M.Sc. Diss. Port. Presentation: 28/08/07 101 p. Advisor: Luiz
Fernando Gomes Soares
Abstract: The several procedural environment proposals for terrestrial Digital
TV Systems led to the middleware framework recommendation known as Globally
Executable MHP (GEM). This standard aims at the harmonization of such
environments allowing the global execution of procedural applications but
neglecting the declarative ones. In this context, this work describes the
integration of the Ginga declarative environment using the API supplied by GEM
and allowing the global execution of declarative contents produced for the
Brazilian System of Digital TV (Sistema Brasileiro de TV Digital).
[07_MSc_pinto]
Rafael Martinelli PINTO. Modelos e algoritmos para análise de congestionamento e
determinação de paradas na logística ferroviária. [Title in English: Models and
algorithms for congestion analysis and stop determination in railroad logistics] M.Sc. Diss. Port. Presentation:
11/04/07 70 p. Advisors: Marcus Vinicius Soledade Poggi de Aragão.
Abstract: Planning in Railway Logistic is an activity with growing importance.
This is due to the high costs of investment to increase the railway capacity.
Nevertheless, planning in this context is a cumbersome task, since a precise
representation is necessary to consider most relevant points in this activity.
Mathematical programming is becoming one of the best ways derive precise
representations and to solve them. This is due to the recent advances on
algorithms and computers used in the resolution of mathematical programming
problems. This dissertation presents models and algorithms for tactical and
strategical railway planning what is done studying a demand planning problem (PPA).
First, this problem is considered assuming that all the railway structure is
defined: the network, the locomotives and wagons available, the yards for
loading and unloading with their respective rates, and the forecast of demands.
Next, the question of deciding the yards to stop is considered. Finally, in a
third step, the effect of congestion in parts of the network is introduced to
the models. This allows analyzing the variation in the travel times and its
consequence in the logistic structure capacity. Models are presented for all
cases of the PPA. Exact and heuristic algorithms, as well as pre-processing
techniques, are described for the problem resolution. In all cases, the
resulting approach allowed to solve the problems optimally or quasi-optimally in
a reasonable computing time. Computational results are presented on a wide set
of real world instances.
[07_MSc_sousa]
Regiane Lima de SOUSA.
Desenvolvimento de aplicações sensíveis ao contexto
usando sistemas multi-agentes. [Title in English:
Context-aware application development using multi-agent systems] M.Sc. Diss. Port. Presentation: 20/09/07 64
p. Advisor: Carlos José Pereira de Lucena.
Abstract: The development of context-aware applications (CAAs) is not a trivial
task due to their intrinsic features, such as openness, asynchrony
communication, and the lack of modular abstractions and mechanisms for the
propagation of context information. On the other hand, a software development
paradigm is actually considered a basic tool for the construction of any
software system. In particular, the Software Engineering for Multi-Agent Systems
(SEMAS) is often introduced as a promising paradigm for the development of
distributed, open, and extensible applications. Software agents are elements
whose execution leads to the reach of the system’s goals, through their
interaction, adaptation, and autonomy properties. From the agent properties, it
becomes possible to provide solutions for the development of CAAs in order to
facilitate the satisfaction of the common requirements mentioned above. This
work has two main purposes: (1) the development of case studies involving the
use of SEMAS for three CAA-specific applications; (2) propose a framework to
support the reuse of context-awareness features in the CAAs. The evaluation of
the case studies and of the framework is used for the demonstration of SEMAS
usability in the CAA-specific domain. Some evidences about the generality of the
results are also provided, beyond the quantitative measurements based on common
quality attributes, such as the modularity.
[07_MSc_novais]
Renato Lima NOVAIS. Coordenação de workflows em ambientes com suporte a
dispositivos móveis. [Title in English: Workflow coordination in environments
with support for mobile devices] M.Sc. Diss. Port. Presentation: 16/03/07 117 p. Advisor:
Marco Antonio Casanova
Abstract: Workflow technology is heavily used to support many process within
organizations. One frequently finds processes that need to be executed in places
that are difficult to access or where desktop computers and reliable
Internet are not available, which compilates the automated execution of these
activities. However, the advance of mobile technologies made it possible to
successfully automate such types of activities directly in the field. The
purpose of this work is to investigate questions related to workflow management
systems in environments with support for disconnected operation using mobile
devices.
[07_MSc_gralhoz]
Ricardo Augusto Rodrigues GRALHOZ. LawML: uma
linguagem para a modelagem de leis de interação em sistemas multi-agentes
abertos LawML [Title in English: A language for modeling interaction laws
in open multi-agent systems] M.Sc. Diss. Port.
Presentation: 31/07/07 200 p. Advisors: Carlos José Pereira de Lucena e
Ivan Mathias Filho.
Abstract: The paradigm of agents appeared while aiming to satisfy the need for
new abstractions for the development of complex and distributed systems. To
manage with the unpredictable behavior of open multi-agent systems, governance
mechanisms are used in the regulation of interactions between agents. This is
due to the concurrent and asynchronous characteristics of these systems, which
are formed by several agents who can act autonomically and can interact with
each other to reach individual goals. In the majority of approaches, the
governance rules are specified with declarative languages or new graphical
representations, which can make this task costly and can make the use of these
governance mechanisms difficult. This essay presents the LawML, a modeling
language based on UML for the specification of rules for interactions between
agents, which is aimed to facilitate the modeling task and, therefore, to
facilitate the use of a specific governance mechanism based on interaction laws.
A set of transformation rules is presented in addition to the language to allow
the graphical interaction law models to be tranformed into the declarative
language of the governance mechanism, the XMLaw
format code. To allow the model-driven development of interaction laws, it is
presented the LawGenerator, a tool for the automatic transformation of the law
model, based on these transformation rules. Finally, this approach is applied to
a case study based on a real distributed system, the Brazilian Central Bank
SELIC system, with the characteristics of an open multi-agent system.
[07_PhD_paes]
Rodrigo de Barros PAES. Governança de sistemas multi-agentes abertos com
fidedignidade. Ph.D. Thesis. Port. Presentation: 02/10/07 196 p. Advisor: Carlos
José Pereira de Lucena.
Abstract: Open multi-agent systems are frequently characterized by having little
or no control over the behavior of the agents. The internal implementation and
architecture of agents usually are inaccessible, and different teams may have
developed them but with no coordination between them. Furthermore, agents may
enter or leave the system at their will. A governance approach defines the
interaction rules that must be obeyed by the agents. These rules allow for a
greater contol and predictability of the observable system behavior. In this
thesis, we propose a governance approach to deal not only with the monitoring
and control of agents' behavior but also to deal with dependability concerns.
The original definition of dependability is the ability to deliver service that
can justifiably be trusted. A governance approach that also with dependability
has as main benefit the reuse of the monitoring and enforcement present in the
governance infrastructure for dependability. We present a case study in the
context of an air traffic control system to illustrate our approach.
[07_MSc_santos]
Rodrigo Borges da Silva SANTOS. Sistema de controle de versões para edição
cooperativa de vídeo MPEG-2. [Title in English: Version control system for
cooperative MPEG-2 video editing] M.Sc. Diss. Port. Presentation: 15/03/07 110 p. Advisor:
Luiz Fernando Gomes Soares and Marco Antonio Casanova.
Abstract: Technological advances in areas such as capture, storage and
compression of digital video are stimulating the development of new services and
systems for manipulation and management of huge amount of video data. An example
of this, are the systems of management, editing and sharing of versions used by
producers of audiovisual content. However, such functional requirements are not
found in one system. This work describes a system that makes possible the
cooperative edition of audiovisual data in MPEG-2 format, allowing the version
control, visualization and manipulation of its content by segments. This
collaborative system still has advantages as the division of tasks between
editors, the fusion of different versions and the extraction of information of
authorship from each version.
[07_MSc_guimaraes]
Rodrigo Laiola GUIMARÃES. Composer: um ambiente de autoria de documentos NCL
para TV digital interativa. [Title in English: Composer: an authoring tool of
NCL documents for interactive digital TV] M.Sc. Diss. Port. Presentation: 13/06/07
106 p. Advisor:
Luiz Fernando Gomes Soares.
Abstract: With the advent of adoption of an interactive digital TV standard by
the Brazilian government, the interest for the analysis of possible alternatives
in several areas that compose a digital TV system has increased. In the case of
Brazil, NCL is the declarative language adopted for modeling interactive
applications in the Brazilian Terrestrial Digital TV System (ISDTV-T-
International System for Digital TV). In that context, this work presents
Composer, an authoring tool to create NCL documents for interactive digital TV.
In the same way that in the HyperProp editor, in which it is based, in Composer
the abstractions are defined using views that allow to simulate a
specific type of edition (structural, temporal, layout and textual). Those
visions work in a synchronized way, in order to ofter an integrated authoring
tool. Besides having the user and the functional interface remodeled, mainly its
temporal view, problems of representation and edition of media objects,
relationship problems, amongst then the interactive relationships, and live
edition are treated. In summary, the proposed system tries to make easier the
creation of documents for digital TV abstracting from the author all, or at
least some complexity of programming in NCL using this authoring tool.
[07_MSc_velloso]
Susana Rosich Soares VELLOSO. SQLLOMining: obtenção de objetos de aprendizagem
utilizando técnicas de aprendizado de máquina [Title in English: SQLLOMining:
Finding Learning Objects using machine learning methods]
M.Sc. Diss. Port. Presentation: 27/07/07. 118 p. Advisor:
Rubens Nascimento Melo
Abstract: Learning Objects (LOs) are pieces of instructional material like
traditional texts that can be reused in the composition of more complex objects
like classes or courses. There are some difficulties in the process of LO
reutilization. One of them in to find pieces of documents that can be used like
LOs. In this work we present a process that, in search for LOs, starts by
extracting, transforming and loading a text database and then continue
clustering these texts, using a machine learning methods that combines EM (Expectation-Maximization)
and a Bayesian classifier. We implemented that process in a system called "SQLLOMining"
that uses the SQL language and text mining methods in the search for LOs.
[07_MSc_escovedo]
Tatiana ESCOVEDO. IssueNet: um framework para avaliação colaborativa de tarefas
[Title in English: IssueNet: A framework for collaborative task assessment]
M.Sc. Diss. Port. Presentation: 26/07/07 120 p. Advisor: Carlos
José Pereira de Lucena.
Abstract: Currently, the business market is characterized by globalization,
strong competition, fast changes, increasing flow and obsolescence of
information and demanding quality standards and productivity. To follow these
transformations, the school also needs to evolve from the classical model to
Collaborative Learning, in order to form individuals capable to communicating,
working in group for the resolution of complex and interdisciplinary problems,
coordinating the individual work and that of the group, and taking the best
decisions. This research specifically investigates the collaborative evaluation
in learning and working groups, and proposes IssueNet, a collaboration Framework
for the management and collaborative evaluation of tasks. To validate the
contributions brought about
by the Framework, and to investigate what other influences it may have on
learning or working groups, two case-studies using two distinc IssueNet
instances have been carried through. After the analysis of the case-studies and
of the based on the comments of the participants, we have concluded that the
Framework satisfies our expectations by making it possible the collaborative
evaluation in learning or working groups.
[07_PhD_kulesza]
Uirá KULESZA. Uma abordagem orientada a aspectos para o desenvolvimento de
frameworks. [Title in English: An aspect-oriented approach to framework
development] Ph.D. Thesis. Port. Presentation: 25/04/07 205 p. Advisor: Carlos
José Pereira de Lucena.
Abstract: This work proposes a systematic approach to framework development wich
relies on the use of aspect-oriented (AO) techniques. The main goal of the
approach is to improve the extensibility and configurability of object-
oriented (OO) frameworks. It is composed of: (i) a set of guidelines to design
and implement frameworks using aspect-oriented programming; and (ii) a
generative model which allows the automatic instantiation of the framework
and its respective OO and AO variabilities. Our guidelines propose the
definition of extension join points (EJPs) in the framework code, which can be
used to extend the framework basic functionality by means of extension aspects.
The extension aspects are responsible for implementing optional, alternative and
integration crosscutting features required by the framework users. Since such
aspects can be automatically unplugged from the framework code, our approach
makes it easier to customize the framework to specific needs. Three cases
studies are presented to illustrate the applicability of our approach to the
development of frameworks from different domains. The approach is also evaluated
through both a qualitative and a quantitative study. Finally, several lessons
learned and discussions resulting from the use of the approach are described.
[07_PhD_costa]
Vaston Goncalves da COSTA. Compactação de provas lógicas. [Title in English:
Logic proof compactation] Ph.D. Thesis. Port. Presentation: 09/04/07 66 p. Advisor:
Edward Hermann Haeusler.
Abstract: It is well-known that the size of propositional classical proofs can
be huge. Proof theoretical studies discovered exponential gaps between normal or
cut-free proofs and their respective non-normal proofs. The task of automatic
theorem proving is, on the other hand, usually based on the construction of
normal, cut-free or only-atomic-cuts proofs, since this procedure produces less
alternative choices. There are familiar tautologies such that the cut-free proof
is huge while the non-cut-free is small. The aim of this work is to reduce the
weight of proposicional deductions. In this sense we present two methods. The
first, namely vertical method, uses the extension axioms. We present a method
that generates a such extension axiom. The second, namely horizontal method,
adds suitable (propositional) unifi fications modulo variable substitutions.We
also present a method that generates a such unifi fication during the proving
process. The proofs produced correspond in a certain way to non normal proofs (non
cut-free proofs).
[07_MSc_amorim]
Vinci Pegoretti AMORIM. Uma arquitetura flexivel para servicos de replicação de
bases distribuídas heterogêneas. M.Sc. Diss. Port. Presentation: 19/03/07 60 p.
Advisor: Marco Antonio Casanova.
Abstract: The replication services available acquire high maturity and
performance levels. However, they do not work with heterogeneous data bases.
This dissertation first describes a software architecture that focus on how to
provide replication services for heterogeneous bases. To obtain high scalability
and to maintain simplicity, the architecture follows a multi-agent structure and
adopts a domain-driven design approach. Then, the dissertation
describes a reference implementation and discusses the technical decisions
adopted, focusing on version control problems, consistency verification and
specific business-oriented rules. The dissertation also describes utilities that
facilitate the configuration and maintenance of the replication system.
[07_MSc_barroso]
Vitor Barata Ribeiro Blanco BARROSO. Geração de sombras em tempo real para
modelos CAD. M.Sc. Diss. Port. Presentation: 02/04/07 86 p. Advisor: Waldemar
Celes Filho
Abstract: Shadow mapping is a widely used rendering technique for shadow
generation on arbitrary surfaces. However, because of the limited resolution
available for sampling the scene, the algorithm presents two difficult
problems to be solved: the incorrect self-shadowing of objects and the jagged
appearance of shadow borders, also known as aliasing. Generating shadows for CAD
(Computer-Aied Design) models presents additional challenges, due to the
existence of many thin complex-silhouette objects and the high depth complexity.
In this work, we present a detailed analysis of self-shadowing and aliasing by
reviewing and building on works from different authors. We
also propose some improvements to existing algorithms: sample alignment without
vertex shaders, a generalized parameter for the LiSPSM (Light-Space Perspective
Shadow Map) algorithm, and an adaptive z-partitioning scheme.
Finally, we investigate the effectiveness of different algorithms when applied
to CAD models, considering ease of implementation, visual quality and
computational efficiency.
[07_MSc_aureliano]
Viviane Cristina Oliveira AURELIANO. eXtreme
communication-centered design: um processo ágil para o projeto da interação
humano-computador. [Title in English: eXtreme Communication-Centered Design: an
agile process for human-computer interaction design] M.Sc. Diss. Port. Presentation:
15/06/07 162 p. Advisor: Simone Diniz Junqueira Barbosa.
Abstract: Interactive software development can follow different kinds of
processes, from specification-driven approaches (traditional methods) to
prototype-driven approaches (agile methods). Due to the emphasis in
documentation since its initial phases, traditional methods allow for more
reflection on the software before its implementation and contribute to better
maintainability. On the other hand, agile methods have reduced documentation,
concentrating mainly on the implementation of the system, in order to increase
the productivity in the software development process. As software becomes more
interactive and accessible to a wider range of users, human-computer interaction
(HCI) concerns have been gaining emphasis in the software development process.
However, schedule and budget restrictions limit the application of known and
accepted HCI techniques. As a consequence, and similar to what happened with
software development processes, there has been a tendency to adopt simplified
usability practices, such as checklists and guidelines. In order to deal with
such concerns at design time, and in a way that is not so simplified, this work
unites some advantages of different kinds of software development processes to
define an HCI design process. This process brings together the support for
reflection given by the Semiotic Engineering (SemEng) theory and the agility of
interface prototype techniques, incorporating the values and practices from
agile methods, more specifically of the eXtreme Programming (XP) development
process.