Scientific works

List of works by Lesandro Ponciano.

First author works Co-authored works Notes Datasets Thesis Reports

First author publications

List of works lead by Lesandro Ponciano (sole or first author).

How citizens engage with the social media presence of climate authorities: the case of five Brazilian cities (npj Climate Action, 2023, DOI:10.1038/s44168-023-00080-3)
The study seeks evidence from practice on how climate authorities have dealt with the challenge of communicating with citizens through social media. It focuses on two research questions: (1) What publication patterns emerge when local-government authorities communicate to the citizens through social media publications? (2) How do citizens respond to authorities’ publications? The questions are framed in the Social Media Presence and Human Engagement conceptual frameworks. The study is based on data from 5 authorities, 10k posts and 5k replies from 2k citizens over a year. It characterises how climate authorities and citizens interact in social media for climate preparedness and resilience and discusses the suitability of social media for climate communication. | (Author PDF)
Characterising Volunteers’ Task Execution Patterns Across Projects on Multi-Project Citizen Science Platforms (Brazilian Symposium on Human Factors in Computing Systems, 2019, DOI: 10.1145/3357155.3358441)
The research focuses on human engagement in citizen science platforms over multiple projects (cross-project engagement). It builds on results on human engagement on stand-alone projects to define an approach to measuring and analysing citizen engagement platforms that host multiple projects. The study shows to what extent people engage in multiple projects and the implications for citizens, platforms, and projects. | (pre-print)
HCI Support Card Creating and Using a Support Card for Education in Human-Computer Interaction (Workshop on HCI Education, 2019, DOI: 10.5753/ihc.2019.8409)
A reference card to be used in HCI classes.
Agreement-based credibility assessment and task replication in human computation systems (Future Generation Computer Systems, 2018, DOI:10.1016/j.future.2018.05.028)
The paper proposes four metrics for measuring human credibility while executing tasks in a distributed system. The metrics are used in an optimization algorithm that decides when enough replication (or redundant execution) to find the consensual answer to a human computation task. The Pareto front is used to find the best configuration scenarios. The baseline is majority voting. The upper bound is an oracle that knows the correct answer.
Debate Estruturado: Uma Estratégia Pedagógica para Ensino e Aprendizagem de Valores Humanos em Interação Humano-Computador (Workshop on HCI Education, 2018, DOI: 10.5753/ihc.2018.4209)
Structured debate for HCI classes.
Designing for Pragmatists and Fundamentalists Privacy Concerns and Attitudes on the Internet of Things (Brazilian Symposium on Human Factors in Computing Systems, 2017, DOI: 10.1145/3160504.3160545)
It investigates people’s perceptions and concerns about privacy in the context of the Internet of Things. Based on a theoretical conception of human privacy perception, the study designed a set of aspects to be investigated in the internet of things. The empirical research is conducted in Brazil, where the study shows distinct people profiles (unconcerned, fundamentalist, and pragmatics) and features of the internet of things that causes more concern or significantly affects people’s perception of privacy. | (Pre-print)
Volunteers Engagement in Human Computation for Astronomy Projects (Computing in Science and Engineering, 2014, DOI: 10.1109/MCSE.2014.4)
The study characterizes human engagement in two projects (Galaxy Zoo and The Milky Way Project) over years of the project duration. It shows inequality in people’s participation and engagement, measured by days of participation, number of contributions and devoted time. People’s behaviour is modelled in Zipf and Log-normal distributions.
Finding Volunteers Engagement Profiles in Human Computation for Citizen Science Projects (Human Computation, 2014, DOI: 10.15346/hc.v1i2.12)
The research defines metrics to measure the short-term and long-term engagement and employs a clustering approach (K-means, Silhouette and within-cluster sum of squares) to find people engagement profiles in two projects (Galaxy Zoo and The Milky Way Project). It uncovers and describes 5 engagement profiles and discusses their implications for citizen science and human computation.
Considering human aspects on strategies for designing and managing distributed human computation (Journal of Internet Services and Applications, 2014, DOI:10.1186/s13174-014-0010-4)
It is a literature review on human factors in human computation. It articulates many areas of knowledge, including psychology, sociology and computer science, to understand how to design tasks and applications performed by humans as part of a distributed system. Many findings from the scientific literature are structured as guidelines or implications for the design of the system.
Adaptive Task Replication Strategy for Human Computation (Brazilian Symposium on Computer Networks and Distributed Systems, 2014)
The study presents an approach to replicate tasks in human computation systems focused on minimising the number of replicas and reduce the waste of human effort on excessive replication of easy tasks.
BitTorrent traffic from a caching perspective (Journal of the Brazilian Computer Society, 2013, DOI:10.1007/s13173-013-0112-z )
The paper is an in-depth analysis of caching BitTorrent traffic. It reports many experiments with caching, such as cache sizes, cache replacement policies (e.g. LRU, LFU, Size), and the number of different people under the Internet Service Provider (ISP) in which the cache is set up. Theoretical analyses of cacheability (byte hit rate as a function of cache size), temporal locality (LRUSM) and reference locality (object popularity) are also carried out.
Assessing Green Strategies in Peer-to-Peer Opportunistic Grids (Journal of grid computing, 2013, DOI:10.1007/s10723-012-9218-3)
The paper discusses the effectiveness of many energy-saving (green) strategies by considering peer-to-peer distributed computing systems. For example, besides ACPI-compliant sleeping states, it discusses timeout policies and peer-oriented strategies. The strategies’ effects on energy saving, task makespan, and disk lifetime are discussed.
Energy Efficient Computing through Productivity-Aware Frequency Scaling (International Conference on Cloud and Green Computing, 2012, DOI: 10.1109/CGC.2012.59)
The research proposes a productivity-aware frequency scaling (PAFS) to empower users to dynamically control power consumption based on the application’s productivity needs. It performs CPU Dynamic Frequency Scale (DFS) decoupled from the system and application by changing processor frequency based on a productivity metric. It is compared to OnDemand and Powersave algorithms from Linux and allows for energy saving without compromising performance.
On the impact of energy-saving strategies in opportunistic grids (IEEE/ACM International Conference on Grid Computing, 2010, DOI: 10.1109/GRID.2010.5698003)
The main topic addressed in the paper is design decisions in distributed computing that can allow for saving energy. It addresses three fundamental points: 1) What is the best ACPI-compliant sleeping strategy to use when a machine is idle, and no new task is coming to the system? 2) When a new task arrives, how to choose which machine should be woken up if several options are available? 3) How to decide which tasks to schedule for the available machines (since they have different power consumption when executing the task)? It proposes many strategies that the system can use in these situations to save energy.
Análise de Estratégias de Computação Verde em Grades Computacionais Oportunistas (Brazilian Symposium on Computer Networks and Distributed Systems, 2010)
The research reported in the paper is an investigation of the design space of green strategies on opportunistic grids. It shows opportunities to save energy and improve grid energy efficiency during periods of low resource contention.| pdf
Técnica de Caracterização de Cargas de Trabalho de Supercomputadores para Predição do Comportamento de Tarefas Paralelas. (Revista Eletrônica de Iniciação Científica, 2009) | PDF.
Análise de algoritmos de classificação e agrupamento na modelagem e predição de comportamentos em cargas de trabalho de máquinas paralelas (Iniciação Científica: destaques 2008. 17ed.Belo Horizonte: Editora PUC Minas, 2009)| PDF
Avanço e exclusão: duas faces da era digital - um análise sociotécnica das TICs. (Iniciação Científica: destaques 2006. 14ed. Belo Horizonte: Editora PUC Minas, 2007). | PDF

Co-authored works

Modeling and Evaluating Personas with Software Explainability Requirements (Iberoamerican Workshop Human-Computer Interaction, 2021)
The paper employs qualitative and qualitative studies to investigate how to design user representations to guide software designers that must be self-explainable. An approach for building personas based on aggregated empathy maps is proposed and employed in a case study. Both designers and users evaluate the resulting personas.
Experiences and insights from using Github Classroom to support Project-Based Courses (International Workshop on Software Engineering Education for the Next Generation (SEENG), 2021).
Exploring User Profiles Based on their Explainability Requirements (Brazilian Symposium on Human Factors in Computing, 2020)
The paper employs questionaries to investigate users’ perceptions about software explainability and uses the k-means algorithm to cluster the answers and identify users’ profiles according to their perceptions. The results show the diversity of users’ perceptions and requirements regarding software explainability.
Defamiliarization, Representation Granularity, and User Experience (IEEE Pacific Visualization Symposium, 2019)
The paper reports a qualitative study on people’s perceptions of visualizations. The visualization explores elements of the level of familiarity with the people and the granularity of displayed information.
Estratégias de obtenção de um item máximo em Computação por Humanos (Brazilian Symposium on Computer Networks and Distributed Systems, 2013)
The paper discusses approaches to find the max item (1-top, the best, the biggest, the most representative, the most beautiful, etc) in human computation.
Análise da Popularidade, Visibilidade e Atividade de Diferentes Tipos de Robôs na Rede Social Twitter (Simpósio Brasileiro de Sistemas Colaborativos, 2017)
It investigates how people interact with bots on Twitter. The bots are good ones, clearly defined as bots in their profiles and usually with good purposes such as weather condition alert.
Citizen Science Terminology Matters Exploring Key Terms (Citizen science: Theory and practice, 2017)
The study report results from a collaboration among 22 scientists in a multi-national effort to investigate the taxonomy of people’s participation in citizen science worldwide. It discusses the terms used to describe citizen science and citizen scientists in many countries giving context and recognition to different definitions. It became an important paper in the citizen science domain.
O papel do hábito de estudo no desempenho do aluno de programação (Workshop de Educação em Computação, 2013).
Assessing the Impact of the Social Network on Marking Photos as Favorites in Flickr ( Brazilian Symposium on Multimedia and the Web, 2012)
Thes study investigates how the favourite marks on photos posted for the users come from different levels of the social network (from 0 to 4), being the level 0 the followers.

Notes

2023 - Long-term social presence and citizen engagement in multi-level and network governance of climate actions. Short research description in The Journal of Brief Ideas.
2020 - Citizen science from the Iberoamerican perspective: an overview, and insights by the RICAP network. Conference of the European Citizen Science Association
2017 - Short and Long-Term Engagement Among Volunteers in Human Computation Projects. Citizen Science Conference 2017 (CitSci2017). Symposium on Advancing our Global Understanding of Citizen Science Engagement Through Cross Programmatic Research
2013 - Task redundancy strategy based on volunteers’ credibility for volunteer thinking projects. Proceedings of the AAAI Conference on Human Computation and Crowdsourcing
2008 - Descoberta e Predição de Comportamento de Tarefas Paralelas através da Caracterização de Padrões em Cargas de Trabalho. WorkShop de Sistemas Computacionais de Alto Desempenho- Concurso de Trabalhos de Iniciação Científica (WSCAD-CTIC)
2008 - Análise de Algoritmos de Classificação e Agrupamento na Descoberta e Modelagem de Comportamento de Tarefas Paralelas. 16º Seminário de Iniciação Científica da PUC Minas. Belo Horizonte: PUC Minas Pôster do 16º SIC
2007 - Técnica de Caracterização de Carga de Trabalho de Máquinas Paralelas para Extração de Informações Utilizadas por um Escalonador Reconfigurável de Tarefas. Workshop em Sistemas Computacionais de Alto Desempenho (WSCAD) - Concurso de Trabalhos de Iniciação Científica em Arquitetura de Computadores e Computação de Alto Desempenho
Proposta, Implementação e Avaliação de Técnica de Caracterização de Carga de Trabalho (Workload) de Máquinas Paralelas para Extração de Informações Utilizadas por um Escalonador Reconfigurável de Tarefas (RGSA). 15° Seminário de Iniciação Científica da PUC Minas. Belo Horizonte: PUC Minas Pôster do 15º SIC
Avanço e Exclusão: Duas faces da era digital - Uma análise sociotécnica das TICs.14° Seminário de Inciciação Científica. Belo Horizonte: PUC MinasPôster do 14º

Thesis and Dissertation

PhD Thesis - Computação por Humanos na Perspectiva do Engajamento e Credibilidade de Seres Humanos e da Replicação de Tarefas - Alternative keywords: vieses cognitivos, ciência cidadã, erro humano, engajamento cognitivo, projeto de sistemas, fatores humanos, racionalidade limitada e interação humano-computador.
M.Sc Dissertation - Avaliação do Impacto de Estratégias de Economia de Energia em Grades Computacionais Entre-Pares- Alternative keywords: computação distribuída, sustentabilidade ambiental, computação verdade, e-ciência.

Datasets

Reports

2024 - Construindo Capacidade: Dados, Informações e Conhecimentos na Construção e Partilha do Saber. Descrição da apresentação na Master Class de ciência cidadã da Comissão Econômica para a América Latina e o Caribe (CEPAL) das Organizações das Nações Unidas (ONU) e Association of European Research Libraries (LIBER). DOI: 10.5281/zenodo.14571797
2024 - Reflections on community communications for climate adaptation and preparedness through information and communication technologies. The report is a description of a talk in the Pernambuco Seminar on Visualization and Sustainability (PSVS). DOI: 10.5281/zenodo.14571996
2023 - Reflexões sobre o Emprego de Inteligência Artificial em Ciência Participativa e Cidadã. Esse é um texto convidado para a plataforma de Ciência Cidadã Civis/IBICT.
2022 - On Humans, Uncertainty and System Engineering. The report is a description of a talk in the Software Engineering Chair in TU Dresden.
2022 - A participação popular nas Ciências Exatas e Informática e seus efeitos no conhecimento científico e tecnológico. It is a book chapter discussing the importance of public participation in scientific research to fight negationism and conspiracy theories about science. Alternative keywords: Ciência Cidadã, Design Participativo, Ciência Comunitária, Pesquisa Participante, Pesquisa Participativa.
2018 - Perspectivas em Computação Social. It is an opinion story written to the Computer Brasil magazine stating the perspective on social computing. Alternative keywords: computer and society, participation, engagement.
2013 - On the Dynamics of Micro-and Macro-task Human Computation Markets. The report is part of the PhD research. Alternative keywords: micro task-markets, Daily Cycles, Weekly Cycles, Skills distribution in the Crowd of Workers, Skills distribution in the workload, Activity level of requesters.
2012 - Análise do Impacto da Rede Social na Marcação de Fotos como Favoritas no Flickr. The report is part of the FRH Analytics project. Alternative keywords: map-reduce, user generated content systems (UGCs), Distância entre usuários.