The exploration and production of oil and gas lead to many logistics challenges. In the case of t... more The exploration and production of oil and gas lead to many logistics challenges. In the case of the Brazilian offshore production, the operation size and the fact that the exploration occurs up to 300 km apart from the coast make these challenges even greater. There are many thousands of different types of materials, hundreds of suppliers, as well as hundreds of different destinations served by distinct routes. In short, this is a complex system, in which it is necessary to deal with an intrinsically combinatorial problem of sharing resources, such as warehouses, ports and means of transportation. Logistics processes need to deliver the materials in time, making sure that the production is not affected. In addition, operational costs and immobilized capital must be minimized. It is crucial to evaluate distribution probabilities for lead-times, identify bottlenecks and predict the effect of adopting specific policies for supply, picking and transportation. In order to address these issues, it is necessary to answer complex what-if queries that take into account the temporal relations, either specified or dictated by the process dynamics, between the events. Since all operations are logged, a substantial amount of historical data is generated. However, these data do not necessarily cover all situations, simply because certain feasible and relevant combinations of events may not have occurred during the period that data is logged. This motivates the use of simulations that generate huge amounts of data augmenting the (logged) historical data, and making big data analytics necessary. In this paper, we briefly describe the process of model building based on historical data as well as the construction of a simulation engine that permits efficient large scale simulations. The simulation results, together with the logged historical data are subjected to big data analytics in order to create global prediction models. The proposed methodology aims to answer complex what-if queries about the logistics processes with a high degree of efficiency and prediction accuracy. The software tool, based on this methodology, is designed so that a decision maker can interactively detect critical situations and study the global effect of changes in policies. Some examples of queries that can be supported by this research are: (i) estimation of distribution probabilities for lead-times under varied circumstances; and (ii) probability of critical materials shortage during periods of high demand.
In this paper we discuss the scenario of Petroleum Engineering projects of Petrobras, a large Bra... more In this paper we discuss the scenario of Petroleum Engineering projects of Petrobras, a large Brazilian governmental oil & gas company. Based on this scenario, we define a set of requirements and system architecture to guide the construction of a Collaborative Engineering Environment for assisting the control and execution of large and complex in dustrial projects in oil industry, specifically tailored for Petroleum Engineering. The environment is composed by the integration of three different technologies of group work: Workflow Management System, Multimedia Collaborative System and Collaborative Virtual Environments.
O conteúdo dos artigos e seus dados em sua forma, correção e confiabilidade são de responsabilida... more O conteúdo dos artigos e seus dados em sua forma, correção e confiabilidade são de responsabilidade exclusiva dos autores. Permitido o download da obra e o compartilhamento desde que sejam atribuídos créditos aos autores, mas sem a possibilidade de alterá-la de nenhuma forma ou utilizá-la para fins comerciais.
We address extractive summarization of technical documents in the oil and gas industry, a major a... more We address extractive summarization of technical documents in the oil and gas industry, a major and urgent task due to the large volume of critical reports in that industry. We examine five distinct state-of-the-art extractive algorithms; to assess performance, a new open dataset was created using the open access Journal of Petroleum Exploration and Production Technology (JPEPT). Abstracts for papers in this journal were used as ground truths for summarization. Algorithms were refined to work with these documents in the best possible way. Our most effective algorithm achieved a state-of-the-art ROUGE-2 score of 0.123, taking 83 minutes to summarize the entire JPEPT dataset.
In this monograph we discuss the scenario of Petroleum Engineering projects at Petrobras, a large... more In this monograph we discuss the scenario of Petroleum Engineering projects at Petrobras, a large Brazilian governmental oil & gas company. Based on this scenario, we propose a Service-Oriented Architecture (SOA) for a Collaborative Problem Solving Environment (CPSE), that we call Collaborative Engineering Environment (CEE), responsible for controlling and executing specialized engineering projects in the oil&gas industry. The environment is composed by the integration of three different technologies for distributed group work: Scientific Workflow Management System (ScWfMS), Multimedia Collaborative System (MMCS) and Collaborative Virtual Environments (CVE).
The offshore industry is responsible for most of the oil and gas production in Brazil. When the l... more The offshore industry is responsible for most of the oil and gas production in Brazil. When the level of complexity in this industry is high, it has been a precursor to new technologies in recent years. The main objective of the present work is the development of a system for the detection and classification of failures in oil production wells operated with elevation by gas lift. Stacked autoencoders are used and pattern recognition techniques for fault classification, verifying performance metrics and applying cross-validation to check the generalization of the models for the available observations. After the development of the classifiers, high recall values were obtained (much higher than 0.98), which shows the great applicability of the proposed system in detecting failures in offshore production wells. Resumo: A indústria offshoreé responsável pela maior parte da produção de petróleo e gás no Brasil. Devido ao elevado nível de complexidade nessa indústria, ela vem sendo a precursora de novas tecnologias ao longo dosúltimos anos. O presente trabalho tem como objetivo o desenvolvimento de um sistema para detecção de falhas em poços de produção de petróleo operados com elevação por gas lift. São utilizados autoencoders empilhados para redução de dimensionalidade e diferentes técnicas de reconhecimento de padrões, verificando métricas de desempenho dos modelos em observações reais de operação disponíveis. Após o desenvolvimento dos classificadores, obteve-se valores de recall elevado (boa parte superior a 0,98), o que mostra a grande aplicabilidade do sistema proposto em detectar falhas em poços de produção offshore.
There has been an increasing interest in using VR and serious games that mock real scenarios and ... more There has been an increasing interest in using VR and serious games that mock real scenarios and allow professionals to perform operations that previously would only be possible in a real environment. In this kind of VR-enhanced training application, it is possible to identify aspects that are crucial to the quality of the system, which were taken into account in the framework we propose in this paper: SimVR-Trei. The most noticeable, to the enduser, are the user interface (UI) and the 3D navigation/interaction systems, which are key to establishing a valuable experience. Two other crucial aspects in such kind of application are the rules system, paired with the environment simulation, which are responsible for creating a veritable world and enhancing the sense of presence. The rules system is the aspect that relates to the training procedures, in other words, it defines the game logic. The environment simulation creates the behavior of the world in response to the users' actions, which, in some cases, may be provided by an external simulator. Finally, the immersion support system deals with the VR-related issues, such as support for multiple display setups. The challenges imposed by these aspects have been faced during the development of two industrial training applications, leading to the creation of SimVR-Trei framework, which seeks to facilitate the development and the reuse of solutions for common issues in different applications.
Proceedings of the 9th International Conference on Computer Vision Theory and Applications, 2014
Nowadays, underwater maintenance tasks, mostly in the case of oil and gas industries, have been a... more Nowadays, underwater maintenance tasks, mostly in the case of oil and gas industries, have been assisted by computer vision algorithms. An important part of these procedures is the rectification of stereo images, which is the first step in the stereo 3D reconstruction pipeline. Some aspects of the underwater environment make the rectification process difficult: it presents a very noisy scenario; and the equipment is almost textureless. As a result of this demanding scenario, this article proposes a novel technique for a more accurate rectification of a set of images than the state-of-the-art methods. Tests were carried out proving the efficiency of the proposed technique.
Journal of Petroleum Science and Engineering, 2020
This papers deals with the automatic detection and classification of faulty events during the pra... more This papers deals with the automatic detection and classification of faulty events during the practical operation of oil and gas wells and lines. The events considered here are part of the publicly available 3W database developed by Petrobras, the Brazilian oil holding. Seven fault classes are considered, with distinct dynamics and patterns, as well as several instances of normal operation. A random forest classifier is employed with different statistical measures to identify each fault type. Three experiments are devised in order to evaluate the system performance in distinct classification scenarios. An accuracy rate of 94% indicates a successful performance for the proposed system in detecting real events. Also, the system's time of detection was on average 12% of the transient period that precedes the fault steady-state.
Anais do Encontro Nacional de Inteligência Artificial e Computacional (ENIAC), 2020
Classifying sentences in industrial, technical or scientific reports can enhance text mining and ... more Classifying sentences in industrial, technical or scientific reports can enhance text mining and information retrieval tasks with useful machinereadable metadata. This paper describes a search engine that employs sentence classification so as to search for abstracts from scholarly papers in Petroleum Engineering. The sentences were classified into four classes, based on the popular IMRAD categories. We produced a dataset containing more than 2,200 manually labeled sentences from 278 scholarly articles in the field of Petroleum Engineering in order to be used as training and testing data. The classifier with best results was logistic regression, with an accuracy of 86.4%. The information retrieval system built on top of the classification system yielded a mAP of 0.80.
2016 XVIII Symposium on Virtual and Augmented Reality (SVR), 2016
Offshore Engineering visualization applications are, in most cases, very complex and should displ... more Offshore Engineering visualization applications are, in most cases, very complex and should display a lot of data coming from very computational intensive numerical simulations. To help analyze and better visualize the results, 3D visualization can be used in conjunction with a VR environment. The main idea for this work began as we realized two different demands that engineering applications had when running on VR setups: firstly, a demand for visualization support in the form of better navigation and better data analysis capabilities. Secondly, a demand for collaboration, due to the difficulties of coordinating a team with one member using VR. To meet these demands, we developed a Service Oriented Architecture (SOA) capable of adding external communications to any application. Using the added communications, we built an external collaboration layer. We study the architecture of our solution and how it could be implemented for any application. Furthermore, we study the impact of our solution when running an Offshore Engineering application on VR setups with the support of mobile devices. Such devices can be used to help navigate the virtual world or be used as a second screen, helping visualize and manipulate large sets of data in the form of tables or graphs. As our test application, we used Environ, which is a VR application for visualization of 3D models and simulations
2016 XVIII Symposium on Virtual and Augmented Reality (SVR), 2016
Training people for working in an oil platform involves teaching operators to locate hundreds of ... more Training people for working in an oil platform involves teaching operators to locate hundreds of devices in a hazardous environment and to correctly operate them. One small mistake can seriously hurt or kill somebody and compromise the integrity of the plant. On the other hand, access to real platforms is restricted and trainees need to relay on photos and diagrams in order to learn, which does not provide a realistic environment to completely allow them to understand their job. Realistic simulated training using Virtual Reality in areas such as aviation has shown that workers can better understand the physical environment and tasks they have to accomplish, assuring a better understanding of the target system. This paper presents techniques used for a simulation system for an oil platform operation. Several interaction techniques were adapted and implemented to achieve a realistic operation scenario.
Procedings of the British Machine Vision Conference 2015, 2015
This paper presents a segmentation technique for flexible pipes in deep underwater environments u... more This paper presents a segmentation technique for flexible pipes in deep underwater environments using low-light monochrome cameras. The technique relies on an alternating pattern of black and white regions marked over the pipe and is divided into three stages: a pre-processing stage for image noise-reduction; a multi-level topological binarization for collecting pipe region candidates; and a backtracking search constrained by inherent pipe characteristics for segmenting its regions. The proposed technique has been tested using video sequences from a real offshore operation and succeeded in segmenting 95.29% of the frames, while local adaptive thresholding methods achieved, at best, a rate of 68.49%.
Big data analytics, applied in the industry to leverage data collection, processing and analysis,... more Big data analytics, applied in the industry to leverage data collection, processing and analysis, can allow a better understanding of production system's abnormal behavior. This knowledge is essential for the adoption of a proactive maintenance approach instead of conventional time-based strategies, leading to a paradigm shift towards Condition-Based Maintenance (CBM) since decision is now based on the usage of a huge, diverse, and dynamic amounts of data as a means to optimize operational costs. This paper reports an investigation of the emerging aspects in the design and implementation of big data analytics solutions for offshore installations in order to allow predictive maintenance practices. Condition-based maintenance focuses on performing interventions based on the actual and future states (health) of a system by monitoring the underlying deterioration processes. One of the building blocks of a CBM design and implementation is the prognostic approach/system, which aims to...
Figure 1: Our approach enables creating multimedia annotations and provides a tree-based structur... more Figure 1: Our approach enables creating multimedia annotations and provides a tree-based structure to support traceability in decision making. (a) An annotation in the VE, created by user "Obama". It also shows how to create a new annotation. (b) Annotation as it is playing. It relies on camera movements (synchronized with audio) to show an anomaly in the model. (c) The discussion structure. Balloons indicate annotations' type and colors denote arguments' type (Pro, Con, +Info). The user is adding a (fourth) positive argument (Pro) with an audio annotation, as it can be seen by active buttons. Abstract Globalization has transformed engineering design into a worldwide endeavor pursued by geographically distributed specialist teams. Widespread adoption of VR for design and the need to act and place marks directly on the objects of discussion in design reviewing tasks led to research on annotations in virtual collaborative environments. However, conventional approache...
The exploration and production of oil and gas lead to many logistics challenges. In the case of t... more The exploration and production of oil and gas lead to many logistics challenges. In the case of the Brazilian offshore production, the operation size and the fact that the exploration occurs up to 300 km apart from the coast make these challenges even greater. There are many thousands of different types of materials, hundreds of suppliers, as well as hundreds of different destinations served by distinct routes. In short, this is a complex system, in which it is necessary to deal with an intrinsically combinatorial problem of sharing resources, such as warehouses, ports and means of transportation. Logistics processes need to deliver the materials in time, making sure that the production is not affected. In addition, operational costs and immobilized capital must be minimized. It is crucial to evaluate distribution probabilities for lead-times, identify bottlenecks and predict the effect of adopting specific policies for supply, picking and transportation. In order to address these issues, it is necessary to answer complex what-if queries that take into account the temporal relations, either specified or dictated by the process dynamics, between the events. Since all operations are logged, a substantial amount of historical data is generated. However, these data do not necessarily cover all situations, simply because certain feasible and relevant combinations of events may not have occurred during the period that data is logged. This motivates the use of simulations that generate huge amounts of data augmenting the (logged) historical data, and making big data analytics necessary. In this paper, we briefly describe the process of model building based on historical data as well as the construction of a simulation engine that permits efficient large scale simulations. The simulation results, together with the logged historical data are subjected to big data analytics in order to create global prediction models. The proposed methodology aims to answer complex what-if queries about the logistics processes with a high degree of efficiency and prediction accuracy. The software tool, based on this methodology, is designed so that a decision maker can interactively detect critical situations and study the global effect of changes in policies. Some examples of queries that can be supported by this research are: (i) estimation of distribution probabilities for lead-times under varied circumstances; and (ii) probability of critical materials shortage during periods of high demand.
In this paper we discuss the scenario of Petroleum Engineering projects of Petrobras, a large Bra... more In this paper we discuss the scenario of Petroleum Engineering projects of Petrobras, a large Brazilian governmental oil & gas company. Based on this scenario, we define a set of requirements and system architecture to guide the construction of a Collaborative Engineering Environment for assisting the control and execution of large and complex in dustrial projects in oil industry, specifically tailored for Petroleum Engineering. The environment is composed by the integration of three different technologies of group work: Workflow Management System, Multimedia Collaborative System and Collaborative Virtual Environments.
O conteúdo dos artigos e seus dados em sua forma, correção e confiabilidade são de responsabilida... more O conteúdo dos artigos e seus dados em sua forma, correção e confiabilidade são de responsabilidade exclusiva dos autores. Permitido o download da obra e o compartilhamento desde que sejam atribuídos créditos aos autores, mas sem a possibilidade de alterá-la de nenhuma forma ou utilizá-la para fins comerciais.
We address extractive summarization of technical documents in the oil and gas industry, a major a... more We address extractive summarization of technical documents in the oil and gas industry, a major and urgent task due to the large volume of critical reports in that industry. We examine five distinct state-of-the-art extractive algorithms; to assess performance, a new open dataset was created using the open access Journal of Petroleum Exploration and Production Technology (JPEPT). Abstracts for papers in this journal were used as ground truths for summarization. Algorithms were refined to work with these documents in the best possible way. Our most effective algorithm achieved a state-of-the-art ROUGE-2 score of 0.123, taking 83 minutes to summarize the entire JPEPT dataset.
In this monograph we discuss the scenario of Petroleum Engineering projects at Petrobras, a large... more In this monograph we discuss the scenario of Petroleum Engineering projects at Petrobras, a large Brazilian governmental oil & gas company. Based on this scenario, we propose a Service-Oriented Architecture (SOA) for a Collaborative Problem Solving Environment (CPSE), that we call Collaborative Engineering Environment (CEE), responsible for controlling and executing specialized engineering projects in the oil&gas industry. The environment is composed by the integration of three different technologies for distributed group work: Scientific Workflow Management System (ScWfMS), Multimedia Collaborative System (MMCS) and Collaborative Virtual Environments (CVE).
The offshore industry is responsible for most of the oil and gas production in Brazil. When the l... more The offshore industry is responsible for most of the oil and gas production in Brazil. When the level of complexity in this industry is high, it has been a precursor to new technologies in recent years. The main objective of the present work is the development of a system for the detection and classification of failures in oil production wells operated with elevation by gas lift. Stacked autoencoders are used and pattern recognition techniques for fault classification, verifying performance metrics and applying cross-validation to check the generalization of the models for the available observations. After the development of the classifiers, high recall values were obtained (much higher than 0.98), which shows the great applicability of the proposed system in detecting failures in offshore production wells. Resumo: A indústria offshoreé responsável pela maior parte da produção de petróleo e gás no Brasil. Devido ao elevado nível de complexidade nessa indústria, ela vem sendo a precursora de novas tecnologias ao longo dosúltimos anos. O presente trabalho tem como objetivo o desenvolvimento de um sistema para detecção de falhas em poços de produção de petróleo operados com elevação por gas lift. São utilizados autoencoders empilhados para redução de dimensionalidade e diferentes técnicas de reconhecimento de padrões, verificando métricas de desempenho dos modelos em observações reais de operação disponíveis. Após o desenvolvimento dos classificadores, obteve-se valores de recall elevado (boa parte superior a 0,98), o que mostra a grande aplicabilidade do sistema proposto em detectar falhas em poços de produção offshore.
There has been an increasing interest in using VR and serious games that mock real scenarios and ... more There has been an increasing interest in using VR and serious games that mock real scenarios and allow professionals to perform operations that previously would only be possible in a real environment. In this kind of VR-enhanced training application, it is possible to identify aspects that are crucial to the quality of the system, which were taken into account in the framework we propose in this paper: SimVR-Trei. The most noticeable, to the enduser, are the user interface (UI) and the 3D navigation/interaction systems, which are key to establishing a valuable experience. Two other crucial aspects in such kind of application are the rules system, paired with the environment simulation, which are responsible for creating a veritable world and enhancing the sense of presence. The rules system is the aspect that relates to the training procedures, in other words, it defines the game logic. The environment simulation creates the behavior of the world in response to the users' actions, which, in some cases, may be provided by an external simulator. Finally, the immersion support system deals with the VR-related issues, such as support for multiple display setups. The challenges imposed by these aspects have been faced during the development of two industrial training applications, leading to the creation of SimVR-Trei framework, which seeks to facilitate the development and the reuse of solutions for common issues in different applications.
Proceedings of the 9th International Conference on Computer Vision Theory and Applications, 2014
Nowadays, underwater maintenance tasks, mostly in the case of oil and gas industries, have been a... more Nowadays, underwater maintenance tasks, mostly in the case of oil and gas industries, have been assisted by computer vision algorithms. An important part of these procedures is the rectification of stereo images, which is the first step in the stereo 3D reconstruction pipeline. Some aspects of the underwater environment make the rectification process difficult: it presents a very noisy scenario; and the equipment is almost textureless. As a result of this demanding scenario, this article proposes a novel technique for a more accurate rectification of a set of images than the state-of-the-art methods. Tests were carried out proving the efficiency of the proposed technique.
Journal of Petroleum Science and Engineering, 2020
This papers deals with the automatic detection and classification of faulty events during the pra... more This papers deals with the automatic detection and classification of faulty events during the practical operation of oil and gas wells and lines. The events considered here are part of the publicly available 3W database developed by Petrobras, the Brazilian oil holding. Seven fault classes are considered, with distinct dynamics and patterns, as well as several instances of normal operation. A random forest classifier is employed with different statistical measures to identify each fault type. Three experiments are devised in order to evaluate the system performance in distinct classification scenarios. An accuracy rate of 94% indicates a successful performance for the proposed system in detecting real events. Also, the system's time of detection was on average 12% of the transient period that precedes the fault steady-state.
Anais do Encontro Nacional de Inteligência Artificial e Computacional (ENIAC), 2020
Classifying sentences in industrial, technical or scientific reports can enhance text mining and ... more Classifying sentences in industrial, technical or scientific reports can enhance text mining and information retrieval tasks with useful machinereadable metadata. This paper describes a search engine that employs sentence classification so as to search for abstracts from scholarly papers in Petroleum Engineering. The sentences were classified into four classes, based on the popular IMRAD categories. We produced a dataset containing more than 2,200 manually labeled sentences from 278 scholarly articles in the field of Petroleum Engineering in order to be used as training and testing data. The classifier with best results was logistic regression, with an accuracy of 86.4%. The information retrieval system built on top of the classification system yielded a mAP of 0.80.
2016 XVIII Symposium on Virtual and Augmented Reality (SVR), 2016
Offshore Engineering visualization applications are, in most cases, very complex and should displ... more Offshore Engineering visualization applications are, in most cases, very complex and should display a lot of data coming from very computational intensive numerical simulations. To help analyze and better visualize the results, 3D visualization can be used in conjunction with a VR environment. The main idea for this work began as we realized two different demands that engineering applications had when running on VR setups: firstly, a demand for visualization support in the form of better navigation and better data analysis capabilities. Secondly, a demand for collaboration, due to the difficulties of coordinating a team with one member using VR. To meet these demands, we developed a Service Oriented Architecture (SOA) capable of adding external communications to any application. Using the added communications, we built an external collaboration layer. We study the architecture of our solution and how it could be implemented for any application. Furthermore, we study the impact of our solution when running an Offshore Engineering application on VR setups with the support of mobile devices. Such devices can be used to help navigate the virtual world or be used as a second screen, helping visualize and manipulate large sets of data in the form of tables or graphs. As our test application, we used Environ, which is a VR application for visualization of 3D models and simulations
2016 XVIII Symposium on Virtual and Augmented Reality (SVR), 2016
Training people for working in an oil platform involves teaching operators to locate hundreds of ... more Training people for working in an oil platform involves teaching operators to locate hundreds of devices in a hazardous environment and to correctly operate them. One small mistake can seriously hurt or kill somebody and compromise the integrity of the plant. On the other hand, access to real platforms is restricted and trainees need to relay on photos and diagrams in order to learn, which does not provide a realistic environment to completely allow them to understand their job. Realistic simulated training using Virtual Reality in areas such as aviation has shown that workers can better understand the physical environment and tasks they have to accomplish, assuring a better understanding of the target system. This paper presents techniques used for a simulation system for an oil platform operation. Several interaction techniques were adapted and implemented to achieve a realistic operation scenario.
Procedings of the British Machine Vision Conference 2015, 2015
This paper presents a segmentation technique for flexible pipes in deep underwater environments u... more This paper presents a segmentation technique for flexible pipes in deep underwater environments using low-light monochrome cameras. The technique relies on an alternating pattern of black and white regions marked over the pipe and is divided into three stages: a pre-processing stage for image noise-reduction; a multi-level topological binarization for collecting pipe region candidates; and a backtracking search constrained by inherent pipe characteristics for segmenting its regions. The proposed technique has been tested using video sequences from a real offshore operation and succeeded in segmenting 95.29% of the frames, while local adaptive thresholding methods achieved, at best, a rate of 68.49%.
Big data analytics, applied in the industry to leverage data collection, processing and analysis,... more Big data analytics, applied in the industry to leverage data collection, processing and analysis, can allow a better understanding of production system's abnormal behavior. This knowledge is essential for the adoption of a proactive maintenance approach instead of conventional time-based strategies, leading to a paradigm shift towards Condition-Based Maintenance (CBM) since decision is now based on the usage of a huge, diverse, and dynamic amounts of data as a means to optimize operational costs. This paper reports an investigation of the emerging aspects in the design and implementation of big data analytics solutions for offshore installations in order to allow predictive maintenance practices. Condition-based maintenance focuses on performing interventions based on the actual and future states (health) of a system by monitoring the underlying deterioration processes. One of the building blocks of a CBM design and implementation is the prognostic approach/system, which aims to...
Figure 1: Our approach enables creating multimedia annotations and provides a tree-based structur... more Figure 1: Our approach enables creating multimedia annotations and provides a tree-based structure to support traceability in decision making. (a) An annotation in the VE, created by user "Obama". It also shows how to create a new annotation. (b) Annotation as it is playing. It relies on camera movements (synchronized with audio) to show an anomaly in the model. (c) The discussion structure. Balloons indicate annotations' type and colors denote arguments' type (Pro, Con, +Info). The user is adding a (fourth) positive argument (Pro) with an audio annotation, as it can be seen by active buttons. Abstract Globalization has transformed engineering design into a worldwide endeavor pursued by geographically distributed specialist teams. Widespread adoption of VR for design and the need to act and place marks directly on the objects of discussion in design reviewing tasks led to research on annotations in virtual collaborative environments. However, conventional approache...
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