After obtaining his Ph.D. degree in 1998, and with over six years of experience as an Instructor and Assistant Professor in Argentina, Gabriel A. Wainer joined Carleton University in July of 2000 as Assistant Professor. He got Tenured in July 2004, and promoted to the rank of Associate Professor in July 2005 and Full Professor in July 2012.

Prof. Wainer started his research career in the field of Real-Time (RT) Operating Systems (OS) and RT scheduling in 1993 at the University of Buenos Aires, Argentina. With limited resources and self-supervised, his research focused on scheduling algorithms and services implemented in the first open-source version of an RTOS (called RT-Minix). These results were published in 16 research papers and a book. Shortly after, these ideas were followed by other researchers, leading to the development of the initial versions of RT-Linux (the first RTOS kernels used and cited our work, which was unique in 1993 when Linux and open-source software were still in their infancy). RT Linux kernels evolved, and work derived from his original research were included in Wind River Systems RTOS. His approach continues to be used and cited, and there have been Real-Time Minix projects based on the concepts Prof. Wainer invented in the '90s until 2020 (e.g. [Mancina, A., Tanenbaum, A.S. et al (2009). Real-Time Systems, 43, 177-210] [L. Kumar K.J, (2019). doi.org:10.47164/ijngc.v10i3.163]).

Since 1996, he contributed to the field of Modeling and Simulation (M&S), introducing Cell-DEVS, a formalism that reduces the complexity of the development of models of physical systems while increasing the speed of their simulations. Prof. Wainer also defined new high-level languages and their mapping into DEVS (a formal Discrete-Event Specification formalism) and Cell-DEVS. This includes the ATLAS traffic language, Petri Nets (timed, colored), Layered Queuing Networks, Timed Automata, Finite State Machines, Bond Graphs; and even a generic environment based on Modelica. This approach allows defining formal models that are discrete-event, spatial, continuous or hybrid, and can be easily combined and reused. Cell-DEVS has been included in different tools. We defined and implemented our own open-source tool, CD++/Cadmium. Cell-DEVS was extended by his students to define other spatial including Centroidal Particle Dynamics and the Tethered Particle System, which allow to define complex particle-based spatial models. CD++/Cadmium has been used to develop models in different domains: epidemiology, ecosystems, 5G wireless networks, resiliency, social interaction, pedestrian flow, architectural design, etc. The software has been used in universities for teaching and research, and in research projects with industry and government agencies (NRC, NRCan, Autodesk, Ericsson, Bentall Kennedy, and others).

Prof. Wainer and his team defined varied algorithms to run these DEVS and Cell-DEVS models in multiprocessor and distributed architectures using varied middleware). The simulation engines now provide the means to run distributed simulations using Web-Services, Cloud and Fog middleware as well as parallel algorithms with high performance. Users can develop and test models in local workstations, submit them to a remote parallel simulator, receive, visualize, and analyze the results locally (using advanced visualization tools). Using distributed coordination algorithms, a model can be split and be simulated remotely in distributed fashion. We defined and built RISE, the first distributed simulation middleware built on RESTful Web Services.

He introduced the DEVStone synthetic benchmark and related tools, which became a de-facto standard to evaluate DEVS simulators and compare their performance from 2005 to this day. DEVStone provides a non-arbitrary method to evaluate the performance of discrete-event simulators by providing model sets with different characteristics, enabling the analysis of specific issues of simulation engines. DEVStone provides a synthetic mechanism for specifying objective ratings for DEVS-based simulators. DEVStone has been implemented in different DEVS tools by software designers to compare the quality of their simulation engines.

Prof. Wainer defined new methods based on modeling and simulation techniques to build RT model prototypes embedded in different platforms. The team defined and implemented a runtime executive integrating models with hardware surrogates (using Intel, ARM, Raspberry Pi and FPGA platforms). We also developed different versions running in multicore hardware, including prototype versions on Intel boards [J30]. We used these prototypes to define a bare hardware version of RT-DEVS models, which allows complete control of the models’ execution without interference of OS or middleware.

The quality of his contributions has also been acknowledged through his participation in a large number of program committees (over 120) and as an invited speaker in more than 80 tutorials, keynotes and invited seminars.

As a consequence of his research activity, he has received numerous awards, including:
- Outstanding Professional Achievement Award by the Society for Modeling and Simulation International (SCS). 2020.
- IEEE Outstanding Engineering Award (Ottawa Section). “For innovative and outstanding contributions to the field of discrete-event modeling and simulation”. 2019.
- ACM Recognition of Service Award. In Appreciation for Contributions to ACM. 2018.
- Nepean’s Canada 150th Anniversary Medal. The medal was given in the 150 anniversary of Canadian Confederation to recognize people who have made a difference in the community or excelled in their professional life in the riding of Nepean, ON, Canada. 2017.
- Fellow, the Society for Modeling and Simulation International (SCS). 2016
- Carleton University Research Achievement Award. 2014.
- Carleton University 2012-3 Faculty Graduate Mentoring Award.
- Distinguished Professional Achievement Award by the Society for Modeling and Simulation International (SCS) “for his numerous citations in the field of discrete-event simulation”. 2013.
- Outstanding Professional Award by the Society for Modeling and Simulation International (only 10 awards given since 1992). 2011.
- The First Bernard P. Zeigler Modeling and Simulation Award, 2010.
- Summersim Leadership Award. 2007.
- Carleton University Research Achievement Award. 2005.
- Numerous Best Paper Awards

He discovered a strong vocation for teaching in the early years of his career. In 1989, being a Teaching Assistant at the Universidad de Buenos Aires (UBA) in Argentina, he started lecturing part-time in different institutions, where he had the chance to organize four different courses. Being a Head Teaching Assistant at the UBA, he organized an Operating Systems Laboratory course devoted to teach design and implementation of Operating Systems. The results of this course (including modifications and improvements to the kernel of an open-source operating system) were unique in Latin America (and one of the few worldwide, winning an international award in 1992). Later, as Instructor at the UBA, he organized new courses on Real-Time Systems, Discrete-Event Simulation and Real-Time Systems Implementation (students in these courses won awards in different contests). As Assistant Professor at the UBA, he completely reorganized the Computer Organization course with excellent results (student projects in this course were published in international conferences and in the ACM Journal of Educational Resources in Computing).

At Carleton, he taught very challenging undergraduate courses with a very large enrollment (since his hiring in July 2000, a total of 1834 students in his courses). He usually obtains high teaching evaluations (an average of 4.21 for his Undergraduate courses, and an average of 4.66/5 for his Graduate courses). He has a particular teaching philosophy, which focuses on extensive class discussion, thinking, analysis and interaction, which provides a better mechanism for understanding and concept retention.

He also had the opportunity to develop a completely new graduate course, which had not been offered before his appointment (SYSC-5104, Methodologies for Discrete-Event Modeling and Simulation). He was able to introduce his own fully developed material, and the students use in-house developed tools to study advanced Modeling and Simulation problems. The best projects in the course are usually improved after the end of the course, and many of them have been accepted for publication in international conferences. Eleven papers have been already published. Two of them obtained awards.

Other teaching activities include a large number of undergraduate student supervision. He has supervised 81 Engineering students, and a large number of co-op students, NSERC undergraduate Scholars, and visiting research scholars (a total of 124 students).

He has always encouraged his students to go beyond standard expectations, and he tries to persuade them to showcase their work. For instance, twelve of his undergraduate projects (4th year, coop) resulted in papers accepted for publication. Many of them participated in conferences presenting the results of their course work. A team participated in the IEEE Computer Society International Design Competition, and new teams will participate in Microsoft's ImagineCup 2012. He is pleased in spending the extra time these activities require, as he believes in trying to leave a positive mark on his students, while providing them with all of the possible support for their future careers.

Over his years spent at Carleton University, he has been called on to participate in many activities and have been assigned various administrative duties. He has participated in numerous committees, including Tenure and Promotion, Scientific Advisory (V-Sim), University Supervisory Approvals Committee, Carleton University IEEE Computer Society Student Branch counselor, and the SCS Student Chapter coordinator. He was also the Department representative on the board of the School of Computer Science, and a member of the Departmental reviewing committee for Endowment, NSERC and OGS Scholarships.

In addition to the above mentioned duties, he has contributed in many other ways. For example, he has been part of the evaluation committees for numerous Engineering projects, Theses, and Ph.D. Comprehensive Examinations. He initiated the Embedded Systems Group and organized around 50 seminars since 2000.

Externally, he is servicing the academic community in different international initiatives. He was the VP Publications of SCS. He is the Editor in Chief of the Transactions of the SCS, and a member of the Editorial Board of various journals. He has been a the organizer of numerous international conferences and workshops. He was also a co-founder of the Symposium of Theory of Modeling and Simulation (TMS/DEVS), SimAUD (Simulation in Architecture and Urban Design), and SimuTools.