2023

1.
Hagedorn, C., Serth, S., Meinel, C.: The Mysterious Adventures of Detective Duke: How Storified Programming MOOCs Support Learners in Achieving Their Learning Goals Frontiers in Education 7, 1016401 (2023)
[ Abstract ] [ BibTeX ] [ URL ] [ DOI ] [ Download ]
 
About 15 years ago, the first Massive Open Online Courses (MOOCs) appeared and revolutionized online education with more interactive and engaging course designs. Yet, keeping learners motivated and ensuring high satisfaction is one of the challenges today's course designers face. Therefore, many MOOC providers employed gamification elements that only boost extrinsic motivation briefly and are limited to platform support. In this article, we introduce and evaluate a gameful learning design we used in several iterations on computer science education courses. For each of the courses on the fundamentals of the Java programming language, we developed a self-contained, continuous story that accompanies learners through their learning journey and helps visualize key concepts. Furthermore, we share our approach to creating the surrounding story in our MOOCs and provide a guideline for educators to develop their own stories. Our data and the long-term evaluation spanning over four Java courses between 2017 and 2021 indicates the openness of learners toward storified programming courses in general and highlights those elements that had the highest impact. While only a few learners did not like the story at all, most learners consumed the additional story elements we provided. However, learners' interest in influencing the story through majority voting was negligible and did not show a considerable positive impact, so we continued with a fixed story instead. We did not find evidence that learners just participated in the narrative because they worked on all materials. Instead, for 10textendash 16% of learners, the story was their main course motivation. We also investigated differences in the presentation format and concluded that several longer audio-book style videos were most preferred by learners in comparison to animated videos or different textual formats. Surprisingly, the availability of a coherent story embedding examples and providing a context for the practical programming exercises also led to a slightly higher ranking in the perceived quality of the learning material (by 4\%). With our research in the context of storified MOOCs, we advance gameful learning designs, foster learner engagement and satisfaction in online courses, and help educators ease knowledge transfer for their learners.
@article{hagedornMysteriousAdventuresDetective2023, abstract = {About 15 years ago, the first Massive Open Online Courses (MOOCs) appeared and revolutionized online education with more interactive and engaging course designs. Yet, keeping learners motivated and ensuring high satisfaction is one of the challenges today's course designers face. Therefore, many MOOC providers employed gamification elements that only boost extrinsic motivation briefly and are limited to platform support. In this article, we introduce and evaluate a gameful learning design we used in several iterations on computer science education courses. For each of the courses on the fundamentals of the Java programming language, we developed a self-contained, continuous story that accompanies learners through their learning journey and helps visualize key concepts. Furthermore, we share our approach to creating the surrounding story in our MOOCs and provide a guideline for educators to develop their own stories. Our data and the long-term evaluation spanning over four Java courses between 2017 and 2021 indicates the openness of learners toward storified programming courses in general and highlights those elements that had the highest impact. While only a few learners did not like the story at all, most learners consumed the additional story elements we provided. However, learners' interest in influencing the story through majority voting was negligible and did not show a considerable positive impact, so we continued with a fixed story instead. We did not find evidence that learners just participated in the narrative because they worked on all materials. Instead, for 10\textendash 16\% of learners, the story was their main course motivation. We also investigated differences in the presentation format and concluded that several longer audio-book style videos were most preferred by learners in comparison to animated videos or different textual formats. Surprisingly, the availability of a coherent story embedding examples and providing a context for the practical programming exercises also led to a slightly higher ranking in the perceived quality of the learning material (by 4\%). With our research in the context of storified MOOCs, we advance gameful learning designs, foster learner engagement and satisfaction in online courses, and help educators ease knowledge transfer for their learners.}, author = {Hagedorn, Christiane and Serth, Sebastian and Meinel, Christoph}, booktitle = {A Paradigm Shift in Designing Education Technology for Online Learning: Opportunities and Challenges}, editor = {Gamage, Dilrukshi}, journal = {Frontiers in Education}, keywords = {sys:relevantfor:its its myown noconference webuniversity}, month = {jan}, pages = 1016401, publisher = {Frontiers}, title = {The Mysterious Adventures of {{Detective Duke}}: {{How}} Storified Programming {{MOOCs}} Support Learners in Achieving Their Learning Goals}, volume = 7, year = 2023 }

2022

1.
Serth, S., Staubitz, T., van Elten, M., Meinel, C.: Measuring the Effects of Course Modularizations in Online Courses for Life-Long Learners Frontiers in Education 7, 1008545 (2022)
[ Abstract ] [ BibTeX ] [ URL ] [ DOI ] [ Download ]
 
Many participants in Massive Open Online Courses are full-time employees seeking greater flexibility in their time commitment and the available learning paths. We recently addressed these requirements by splitting up our 6-week courses into three 2-week modules followed by a separate exam. Modularizing courses offers many advantages: Shorter modules are more sustainable and can be combined, reused, and incorporated into learning paths more easily. Time flexibility for learners is also improved as exams can now be offered multiple times per year, while the learning content is available independently. In this article, we answer the question of which impact this modularization has on key learning metrics, such as course completion rates, learning success, and no-show rates. Furthermore, we investigate the influence of longer breaks between modules on these metrics. According to our analysis, course modules facilitate more selective learning behaviors that encourage learners to focus on topics they are the most interested in. At the same time, participation in overarching exams across all modules seems to be less appealing compared to an integrated exam of a 6-week course. While breaks between the modules increase the distinctive appearance of individual modules, a break before the final exam further reduces initial interest in the exams. We further reveal that participation in self-paced courses as a preparation for the final exam is unlikely to attract new learners to the course offerings, even though learners' performance is comparable to instructor-paced courses. The results of our long-term study on course modularization provide a solid foundation for future research and enable educators to make informed decisions about the design of their courses.
@article{serthMeasuringEffectsCourse2022, abstract = {Many participants in Massive Open Online Courses are full-time employees seeking greater flexibility in their time commitment and the available learning paths. We recently addressed these requirements by splitting up our 6-week courses into three 2-week modules followed by a separate exam. Modularizing courses offers many advantages: Shorter modules are more sustainable and can be combined, reused, and incorporated into learning paths more easily. Time flexibility for learners is also improved as exams can now be offered multiple times per year, while the learning content is available independently. In this article, we answer the question of which impact this modularization has on key learning metrics, such as course completion rates, learning success, and no-show rates. Furthermore, we investigate the influence of longer breaks between modules on these metrics. According to our analysis, course modules facilitate more selective learning behaviors that encourage learners to focus on topics they are the most interested in. At the same time, participation in overarching exams across all modules seems to be less appealing compared to an integrated exam of a 6-week course. While breaks between the modules increase the distinctive appearance of individual modules, a break before the final exam further reduces initial interest in the exams. We further reveal that participation in self-paced courses as a preparation for the final exam is unlikely to attract new learners to the course offerings, even though learners' performance is comparable to instructor-paced courses. The results of our long-term study on course modularization provide a solid foundation for future research and enable educators to make informed decisions about the design of their courses.}, author = {Serth, Sebastian and Staubitz, Thomas and {van Elten}, Martin and Meinel, Christoph}, booktitle = {A Paradigm Shift in Designing Education Technology for Online Learning: Opportunities and Challenges}, editor = {Gamage, Dilrukshi}, journal = {Frontiers in Education}, keywords = {sys:relevantfor:its its myown noconference webuniversity}, month = {oct}, pages = 1008545, publisher = {Frontiers}, title = {Measuring the Effects of Course Modularizations in Online Courses for Life-Long Learners}, volume = 7, year = 2022 }

2.
Koehler, D., Serth, S., Steinbeck, H., Meinel, C.: Integrating Podcasts into MOOCs: Comparing Effects of Audio- and Video-Based Education for Secondary Content In: Hilliger, I., Muñoz-Merino, P.J., Laet, T.D., Ortega-Arranz, A., and Farrell, T. (eds.) Educating for a New Future: Making Sense of Technology-Enhanced Learning Adoption (EC-TEL 2022). pp. 131–144. Springer, Toulouse, France (2022)
[ Abstract ] [ BibTeX ] [ URL ] [ DOI ] [ Download ]
 
Multimedia learning methods can enrich any online learning scenario. However, traditional Massive Open Online Courses (MOOCs) often put the learner into classroom-like situations without considerably varying presentation formats. By conducting a study and analysis of multimedia elements such as interviews and podcasts, we lay a foundation for future research in the field of multimedia learning. This research studies video-based and audio-based education methods for secondary learning content. We explore both the conscious and subconscious effects of the different formats. In our quantitative assessment of more than 900 learners, we did not observe any significant differences in quiz performance between learners of the two groups. Although our recurring learners are used to video-based learning methods, the audio-based teaching methods were accepted and rated “easy to follow” by more than 80% of our learners. However, we observe that the learners enjoy traditional podcasts with a single presenter the least. Our work adds to the field of multimedia online teaching and shows that enriching courses with audio-based education methods proves beneficial for asynchronous learning offers.
@inproceedings{koehlerIntegratingPodcastsMOOCs2022, abstract = {Multimedia learning methods can enrich any online learning scenario. However, traditional Massive Open Online Courses (MOOCs) often put the learner into classroom-like situations without considerably varying presentation formats. By conducting a study and analysis of multimedia elements such as interviews and podcasts, we lay a foundation for future research in the field of multimedia learning. This research studies video-based and audio-based education methods for secondary learning content. We explore both the conscious and subconscious effects of the different formats. In our quantitative assessment of more than 900 learners, we did not observe any significant differences in quiz performance between learners of the two groups. Although our recurring learners are used to video-based learning methods, the audio-based teaching methods were accepted and rated “easy to follow” by more than 80\% of our learners. However, we observe that the learners enjoy traditional podcasts with a single presenter the least. Our work adds to the field of multimedia online teaching and shows that enriching courses with audio-based education methods proves beneficial for asynchronous learning offers.}, address = {Toulouse, France}, author = {Koehler, Daniel and Serth, Sebastian and Steinbeck, Hendrik and Meinel, Christoph}, booktitle = {Educating for a {{New Future}}: {{Making Sense}} of {{Technology-Enhanced Learning Adoption}} ({{EC-TEL}} 2022)}, editor = {Hilliger, Isabel and Muñoz-Merino, Pedro J. and Laet, Tinne De and Ortega-Arranz, Alejandro and Farrell, Tracie}, keywords = {sys:relevantfor:its its myown webuniversity}, month = {09}, pages = {131–144}, publisher = {{Springer}}, title = {Integrating {{Podcasts}} into {{MOOCs}}: {{Comparing Effects}} of {{Audio-}} and {{Video-Based Education}} for {{Secondary Content}}}, volume = 13450, year = 2022 }

3.
Hagedorn, C., Serth, S., Meinel, C.: Breaking the Ice? How to Foster the Sense of Community in MOOCs In: 2022 International Conference on Advanced Learning Technologies (ICALT). pp. 22–26. IEEE, Bucharest, Romania (2022)
[ Abstract ] [ BibTeX ] [ URL ] [ DOI ] [ Download ]
 
Massive Open Online Courses (MOOCs) are usually attended by several thousand learners who barely get to know each other during the course period. Being unaware of fellow learners often results in a low sense of community. In addition, many MOOC learners are afraid of using the course forum, which often is the only participation opportunity in social course activities apart from forming smaller learning groups. Thus, learners can easily be frustrated with the course content when feeling alone. To improve social presence and the sense of community, course instructors can use ice-breaking games. First, this paper evaluates which kind of ice-breaking games can be used in MOOCs. Afterward, we present the results from a first experiment where we use self-reflection sociograms as an icebreaking activity. Most learners perceived the implemented "Self-Reflection Questionnaires" (SRQ) ice-breaker as a positive course feature (68.35%). SRQs increased the sense of community, and learners were satisfied (91.06%) with their perceived community sense level. The SRQs were also helpful for the teaching teams. Our results indicate that further investigation of SRQs is beneficial to explore the provided value for course instructors and their influence on individual MOOC learners and community-building.
@inproceedings{hagedornBreakingIceHow2022, abstract = {Massive Open Online Courses (MOOCs) are usually attended by several thousand learners who barely get to know each other during the course period. Being unaware of fellow learners often results in a low sense of community. In addition, many MOOC learners are afraid of using the course forum, which often is the only participation opportunity in social course activities apart from forming smaller learning groups. Thus, learners can easily be frustrated with the course content when feeling alone. To improve social presence and the sense of community, course instructors can use ice-breaking games. First, this paper evaluates which kind of ice-breaking games can be used in MOOCs. Afterward, we present the results from a first experiment where we use self-reflection sociograms as an icebreaking activity. Most learners perceived the implemented "Self-Reflection Questionnaires" (SRQ) ice-breaker as a positive course feature (68.35%). SRQs increased the sense of community, and learners were satisfied (91.06%) with their perceived community sense level. The SRQs were also helpful for the teaching teams. Our results indicate that further investigation of SRQs is beneficial to explore the provided value for course instructors and their influence on individual MOOC learners and community-building.}, address = {{Bucharest, Romania}}, author = {Hagedorn, Christiane and Serth, Sebastian and Meinel, Christoph}, booktitle = {2022 {{International Conference}} on {{Advanced Learning Technologies}} ({{ICALT}})}, keywords = {sys:relevantfor:its its myown webuniversity}, month = {jul}, pages = {22–26}, publisher = {{IEEE}}, title = {Breaking the {{Ice}}? {{How}} to {{Foster}} the {{Sense}} of {{Community}} in {{MOOCs}}}, year = 2022 }

4.
Staubitz, T., Bothe, M., Elhayany, M., Hagedorn, C., Serth, S., Zobel, T., Meinel, C.: Analysis of the Applicability of General Scaling Laws on Course Size, Completion Rates, and Forum Activity in MOOCs In: Proceedings of the Ninth ACM Conference on Learning @ Scale. pp. 294–298. ACM, New York, USA (2022)
[ Abstract ] [ BibTeX ] [ URL ] [ DOI ] [ Download ]
 
In 2017, Geoffrey West published his book "Scale" in which he examined universal laws of scale in different contexts. Inspired by his keynote in 2021's Learning@Scale conference, we investigated the applicability of these laws in the context of Massive Open Online Courses and learners' behavior. We tested these laws on different learning platforms from academic, enterprise and social, and research contexts. In this paper, we examine course characteristics, such as course size, the completion rate, and the forum activity. We observed that the number of issued certificates scales almost identically on all examined platforms, while forum participation scales slightly different on each of the platforms. In the future, we will perform a deeper analysis on the forum behavior that exceeds a mere quantitative analysis.
@inproceedings{staubitzAnalysisApplicabilityGeneral2022, abstract = {In 2017, Geoffrey West published his book "Scale" in which he examined universal laws of scale in different contexts. Inspired by his keynote in 2021's Learning@Scale conference, we investigated the applicability of these laws in the context of Massive Open Online Courses and learners' behavior. We tested these laws on different learning platforms from academic, enterprise and social, and research contexts. In this paper, we examine course characteristics, such as course size, the completion rate, and the forum activity. We observed that the number of issued certificates scales almost identically on all examined platforms, while forum participation scales slightly different on each of the platforms. In the future, we will perform a deeper analysis on the forum behavior that exceeds a mere quantitative analysis.}, address = {{New York, USA}}, author = {Staubitz, Thomas and Bothe, Max and Elhayany, Mohamed and Hagedorn, Christiane and Serth, Sebastian and Zobel, Theresa and Meinel, Christoph}, booktitle = {Proceedings of the {{Ninth ACM Conference}} on {{Learning}} @ {{Scale}}}, keywords = {sys:relevantfor:its its myown webuniversity}, month = {jun}, pages = {294–298}, publisher = {{ACM}}, title = {Analysis of the {{Applicability}} of {{General Scaling Laws}} on {{Course Size}}, {{Completion Rates}}, and {{Forum Activity}} in {{MOOCs}}}, year = 2022 }

2021

1.
Koehler, D., Serth, S., Meinel, C.: Consuming Security: Evaluating Podcasts to Promote Online Learning Integrated with Everyday Life In: 2021 World Engineering Education Forum/Global Engineering Deans Council (WEEF/GEDC). pp. 476–481. IEEE, Madrid, Spain (2021)
[ Abstract ] [ BibTeX ] [ URL ] [ DOI ] [ Download ]
 
Traditional (online) teaching approaches put the student into a video-based, classroom-like situation. When asked to reproduce the content, the student can consciously remember what he learned and answer accordingly. Contrasting, knowledge of IT-security aspects requires sensitization for the topic throughout the daily life of a learner. We learned from interactions with former learners that they sometimes found themselves in situations where they - despite knowing better - still behaved in an undesired way. We thereby conclude that the classroom-based presentation of knowledge in Massive Open Online Courses (MOOCs) is not sufficient for the field of IT-Security Education. Therefore, this work presents an approach to a study to assess and analyze different audio-based methods of conveying knowledge, which can integrate into a learner's everyday life. In the spirit of Open Research, we therefore publish our research questions and chosen methods in order to discuss these within the community. Following, we will study the perception of the proposed education methods by learners and suggest possible improvements for subsequent research.
@inproceedings{koehlerConsumingSecurityEvaluating2021, abstract = {Traditional (online) teaching approaches put the student into a video-based, classroom-like situation. When asked to reproduce the content, the student can consciously remember what he learned and answer accordingly. Contrasting, knowledge of IT-security aspects requires sensitization for the topic throughout the daily life of a learner. We learned from interactions with former learners that they sometimes found themselves in situations where they - despite knowing better - still behaved in an undesired way. We thereby conclude that the classroom-based presentation of knowledge in Massive Open Online Courses (MOOCs) is not sufficient for the field of IT-Security Education. Therefore, this work presents an approach to a study to assess and analyze different audio-based methods of conveying knowledge, which can integrate into a learner's everyday life. In the spirit of Open Research, we therefore publish our research questions and chosen methods in order to discuss these within the community. Following, we will study the perception of the proposed education methods by learners and suggest possible improvements for subsequent research.}, address = {{Madrid, Spain}}, author = {Koehler, Daniel and Serth, Sebastian and Meinel, Christoph}, booktitle = {2021 {{World Engineering Education Forum}}/{{Global Engineering Deans Council}} ({{WEEF}}/{{GEDC}})}, keywords = {sys:relevantfor:its its myown webuniversity}, month = {nov}, pages = {476–481}, publisher = {{IEEE}}, title = {Consuming {{Security}}: {{Evaluating Podcasts}} to {{Promote Online Learning Integrated}} with {{Everyday Life}}}, year = 2021 }

2.
Serth, S., Köhler, D., Marschke, L., Auringer, F., Hanff, K., Hellenberg, J.-E., Kantusch, T., Paß, M., Meinel, C.: Improving the Scalability and Security of Execution Environments for Auto-Graders in the Context of MOOCs In: Greubel, A., Strickroth, S., and Striewe, M. (eds.) Proceedings of the Fifth Workshop "Automatische Bewertung von Programmieraufgaben" (ABP 2021). pp. 3–10. Gesellschaft für Informatik e.V. (GI), Virtual Event, Germany (2021)
[ Abstract ] [ BibTeX ] [ URL ] [ DOI ] [ Download ]
 
Learning a programming language requires learners to write code themselves, execute their programs interactively, and receive feedback about the correctness of their code. Many approaches with so-called auto-graders exist to grade students' submissions and provide feedback for them automatically. University classes with hundreds of students or Massive Open Online Courses (MOOCs) with thousands of learners often use these systems. Assessing the submissions usually includes executing the students' source code and thus implies requirements on the scalability and security of the systems. In this paper, we evaluate different execution environments and orchestration solutions for auto-graders. We compare the most promising open-source tools regarding their usability in a scalable environment required for MOOCs. According to our evaluation, Nomad, in conjunction with Docker, fulfills most requirements. We derive implications for the productive use of Nomad for an auto-grader in MOOCs.
@inproceedings{serthImprovingScalabilitySecurity2021, abstract = {Learning a programming language requires learners to write code themselves, execute their programs interactively, and receive feedback about the correctness of their code. Many approaches with so-called auto-graders exist to grade students' submissions and provide feedback for them automatically. University classes with hundreds of students or Massive Open Online Courses (MOOCs) with thousands of learners often use these systems. Assessing the submissions usually includes executing the students' source code and thus implies requirements on the scalability and security of the systems. In this paper, we evaluate different execution environments and orchestration solutions for auto-graders. We compare the most promising open-source tools regarding their usability in a scalable environment required for MOOCs. According to our evaluation, Nomad, in conjunction with Docker, fulfills most requirements. We derive implications for the productive use of Nomad for an auto-grader in MOOCs.}, address = {{Virtual Event, Germany}}, author = {Serth, Sebastian and K{ö}hler, Daniel and Marschke, Leonard and Auringer, Felix and Hanff, Konrad and Hellenberg, Jan-Eric and Kantusch, Tobias and Paß, Maximilian and Meinel, Christoph}, booktitle = {Proceedings of the {{Fifth Workshop}} "{{Automatische Bewertung}} von {{Programmieraufgaben}}" ({{ABP}} 2021)}, editor = {Greubel, Andr{é} and Strickroth, Sven and Striewe, Michael}, keywords = {sys:relevantfor:its its myown webuniversity}, month = {oct}, pages = {3–10}, publisher = {{Gesellschaft für Informatik e.V. (GI)}}, title = {Improving the {{Scalability}} and {{Security}} of {{Execution Environments}} for {{Auto}}-{{Graders}} in the {{Context}} of {{MOOCs}}}, volume = 5, year = 2021 }

3.
Serth, S., Teusner, R., Meinel, C.: Impact of Contextual Tips for Auto-Gradable Programming Exercises in MOOCs In: Proceedings of the Eighth ACM Conference on Learning @ Scale. pp. 307–310. ACM, Virtual Event, Germany (2021)
[ Abstract ] [ BibTeX ] [ URL ] [ DOI ] [ Download ]
 
Learners in Massive Open Online Courses offering practical programming exercises face additional challenges next to the actual course content. Beginners have to find approaches to deal with misconceptions and often struggle with the correct syntax while solving the exercises. The paper at hand presents insights from offering contextual tips in a web-based development environment used for practical programming exercises. We measured the effects of our approach in a Python course with 6,000 active students in a hidden A/B test and additionally used qualitative surveys. While a majority of learners valued the assistance, we were unable to show a direct impact on completion rates or average scores. We however noticed that users requesting tips took significantly longer and made more use of other assistance features of the platform than users in our control group. Insights from our study can be used to target beginners with more specific hints and provide additional, context-specific clues as part of the learning material.
@inproceedings{serthImpactContextualTips2021, abstract = {Learners in Massive Open Online Courses offering practical programming exercises face additional challenges next to the actual course content. Beginners have to find approaches to deal with misconceptions and often struggle with the correct syntax while solving the exercises. The paper at hand presents insights from offering contextual tips in a web-based development environment used for practical programming exercises. We measured the effects of our approach in a Python course with 6,000 active students in a hidden A/B test and additionally used qualitative surveys. While a majority of learners valued the assistance, we were unable to show a direct impact on completion rates or average scores. We however noticed that users requesting tips took significantly longer and made more use of other assistance features of the platform than users in our control group. Insights from our study can be used to target beginners with more specific hints and provide additional, context-specific clues as part of the learning material.}, address = {{Virtual Event, Germany}}, author = {Serth, Sebastian and Teusner, Ralf and Meinel, Christoph}, booktitle = {Proceedings of the {{Eighth ACM Conference}} on {{Learning}} @ {{Scale}}}, keywords = {sys:relevantfor:its its myown webuniversity}, month = {jun}, pages = {307–310}, publisher = {{ACM}}, title = {Impact of {{Contextual Tips}} for {{Auto}}-{{Gradable Programming Exercises}} in {{MOOCs}}}, year = 2021 }

4.
Bethge, J., Serth, S., Staubitz, T., Wuttke, T., Nordemann, O., Das, P.-P., Meinel, C.: TransPipe - A Pipeline for Automated Transcription and Translation of Videos In: Proceedings of the 7th European MOOC Stakeholder Summit (EMOOCs 2021). pp. 79–94. Universitätsverlag Potsdam, Potsdam, Germany (2021)
[ Abstract ] [ BibTeX ] [ URL ] [ DOI ] [ Download ]
 
Online learning environments, such as Massive Open Online Courses (MOOCs), often rely on videos as a major component to convey knowledge. However, these videos exclude potential participants who do not understand the lecturer's language, regardless of whether that is due to language unfamiliarity or aural handicaps. Subtitles and/or interactive transcripts solve this issue, ease navigation based on the content, and enable indexing and retrieval by search engines. Although there are several automated speech-to-text converters and translation tools, their quality varies and the process of integrating them can be quite tedious. Thus, in practice, many videos on MOOC platforms only receive subtitles after the course is already finished (if at all) due to a lack of resources. This work describes an approach to tackle this issue by providing a dedicated tool, which is closing this gap between MOOC platforms and transcription and translation tools and offering a simple workflow that can easily be handled by users with a less technical background. The proposed method is designed and evaluated by qualitative interviews with three major MOOC providers.
@inproceedings{bethgeTransPipePipelineAutomated2021, abstract = {Online learning environments, such as Massive Open Online Courses (MOOCs), often rely on videos as a major component to convey knowledge. However, these videos exclude potential participants who do not understand the lecturer's language, regardless of whether that is due to language unfamiliarity or aural handicaps. Subtitles and/or interactive transcripts solve this issue, ease navigation based on the content, and enable indexing and retrieval by search engines. Although there are several automated speech-to-text converters and translation tools, their quality varies and the process of integrating them can be quite tedious. Thus, in practice, many videos on MOOC platforms only receive subtitles after the course is already finished (if at all) due to a lack of resources. This work describes an approach to tackle this issue by providing a dedicated tool, which is closing this gap between MOOC platforms and transcription and translation tools and offering a simple workflow that can easily be handled by users with a less technical background. The proposed method is designed and evaluated by qualitative interviews with three major MOOC providers.}, address = {{Potsdam, Germany}}, author = {Bethge, Joseph and Serth, Sebastian and Staubitz, Thomas and Wuttke, Tobias and Nordemann, Oliver and Das, Partha-Pratim and Meinel, Christoph}, booktitle = {Proceedings of the 7th {{European MOOC Stakeholder Summit}} ({{EMOOCs}} 2021)}, keywords = {sys:relevantfor:its its myown webuniversity}, month = {jun}, pages = {79–94}, publisher = {{Universitätsverlag Potsdam}}, title = {{{TransPipe}} - {{A Pipeline}} for {{Automated Transcription}} and {{Translation}} of {{Videos}}}, year = 2021 }

5.
Serth, S., Staubitz, T., Teusner, R., Meinel, C.: CodeOcean and CodeHarbor: Auto-Grader and Code Repository In: Shaffer, C., Brusilovsky, P., Koedinger, K., and Edwards, S. (eds.) SPLICE 2021 Workshop CS Education Infrastructure for All III: From Ideas to Practice. p. 5. 52nd ACM Technical Symposium on Computer Science Education, Virtual Event (2021)
[ Abstract ] [ BibTeX ] [ URL ] [ Download ]
 
The Hasso Plattner Institute (HPI) successfully operates a MOOC (Massive Open Online Course) platform since 2012. Since 2013, global enterprises, international organizations, governments, and research projects funded by the German ministry of education are partnering with us to operate their own instances of the platform. The focus of our platform instance is on IT topics, which includes programming courses in different programming languages. An important element of these courses are graded hands-on programming assignments. MOOCs, even more than traditional classroom situations, depend on automated solutions to assess programming exercises. Manual evaluation is not an option due to the massive amount of users that participate in these courses. The paper at hand presents two of the tools developed in this context at the HPI: CodeOceantextemdash an auto-grader for a variety of programming languages, and CodeHarbor, a tool to share auto-gradable programming exercises between various online platforms.
@inproceedings{serthCodeOceanCodeHarborAutoGrader2021, abstract = {The Hasso Plattner Institute (HPI) successfully operates a MOOC (Massive Open Online Course) platform since 2012. Since 2013, global enterprises, international organizations, governments, and research projects funded by the German ministry of education are partnering with us to operate their own instances of the platform. The focus of our platform instance is on IT topics, which includes programming courses in different programming languages. An important element of these courses are graded hands-on programming assignments. MOOCs, even more than traditional classroom situations, depend on automated solutions to assess programming exercises. Manual evaluation is not an option due to the massive amount of users that participate in these courses. The paper at hand presents two of the tools developed in this context at the HPI: CodeOcean\textemdash an auto-grader for a variety of programming languages, and CodeHarbor, a tool to share auto-gradable programming exercises between various online platforms.}, address = {Virtual Event}, author = {Serth, Sebastian and Staubitz, Thomas and Teusner, Ralf and Meinel, Christoph}, booktitle = {SPLICE 2021 Workshop CS Education Infrastructure for All III: From Ideas to Practice}, editor = {Shaffer, Cliff and Brusilovsky, Peter and Koedinger, Ken and Edwards, Steve}, keywords = {sys:relevantfor:its its myown webuniversity}, month = {mar}, organization = {SPLICE}, pages = 5, publisher = {52nd ACM Technical Symposium on Computer Science Education}, title = {CodeOcean and CodeHarbor: Auto-Grader and Code Repository}, year = 2021 }

2020

1.
Serth, S., Teusner, R., Meinel, C.: Digitale Arbeitsblätter mit interaktiven Programmieraufgaben im Informatik-Unterricht In: Zender, R., Ifenthaler, D., Leonhardt, T., and Schumacher, C. (eds.) Lecture Notes in Informatics (LNI) - Proceedings: DELFI 2020 – Die 18. Fachtagung Bildungstechnologien der Gesellschaft für Informatik e.V. pp. 235–246. Gesellschaft für Informatik e.V. (GI), Bonn, Germany (2020)
[ Abstract ] [ BibTeX ] [ URL ] [ Download ]
 
Moderner Informatikunterricht umfasst das Erlernen von Grundlagen des Programmierens. Dabei verwenden Lehrer häufig bereits vorhandene Videos, Quizfragen und praktische Programmieraufgaben aus Massive Open Online Courses (MOOCs), obwohl derzeit die Möglichkeiten zur Anpassung der Inhalte und dem Hinzufügen eigener Materialien für Lehrer begrenzt sind. Unsere Software ermöglicht es Lehrern, ihre eigenen interaktiven Arbeitsblätter mit angepassten und eigenen Übungen zu erstellen. Im Rahmen einer praktischen Evaluierung wurde das Konzept von Schülern und Lehrern gleichermaßen gut angenommen: Lehrer hatten mehr Zeit für die Beantwortung individueller Fragen und Schüler konnten in ihrem eigenen Tempo mithilfe automatisierter Rückmeldungen lernen. Für die Vorbereitung zukünftiger Unterrichtsstunden schätzten Lehrer die Möglichkeit, häufige Fehler auszuwerten, um so zuvor unerkannte Probleme besprechen zu können. Interaktive Arbeitsblätter fördern individualisierte Lernprozesse, unterstützen Lehrer in der Unterrichtsgestaltung und sind somit ein wichtiger Bestandteil digitaler Bildung an Schulen.
@inproceedings{serthDigitaleArbeitsblaetterMit2020, abstract = {Moderner Informatikunterricht umfasst das Erlernen von Grundlagen des Programmierens. Dabei verwenden Lehrer häufig bereits vorhandene Videos, Quizfragen und praktische Programmieraufgaben aus Massive Open Online Courses (MOOCs), obwohl derzeit die Möglichkeiten zur Anpassung der Inhalte und dem Hinzufügen eigener Materialien für Lehrer begrenzt sind. Unsere Software ermöglicht es Lehrern, ihre eigenen interaktiven Arbeitsblätter mit angepassten und eigenen Übungen zu erstellen. Im Rahmen einer praktischen Evaluierung wurde das Konzept von Schülern und Lehrern gleichermaßen gut angenommen: Lehrer hatten mehr Zeit für die Beantwortung individueller Fragen und Schüler konnten in ihrem eigenen Tempo mithilfe automatisierter Rückmeldungen lernen. Für die Vorbereitung zukünftiger Unterrichtsstunden schätzten Lehrer die Möglichkeit, häufige Fehler auszuwerten, um so zuvor unerkannte Probleme besprechen zu können. Interaktive Arbeitsblätter fördern individualisierte Lernprozesse, unterstützen Lehrer in der Unterrichtsgestaltung und sind somit ein wichtiger Bestandteil digitaler Bildung an Schulen.}, address = {Bonn, Germany}, author = {Serth, Sebastian and Teusner, Ralf and Meinel, Christoph}, booktitle = {Lecture Notes in Informatics (LNI) - Proceedings: DELFI 2020 – Die 18. Fachtagung Bildungstechnologien der Gesellschaft für Informatik e.V.}, editor = {Zender, Raphael and Ifenthaler, Dirk and Leonhardt, Thiemo and Schumacher, Clara}, keywords = {sys:relevantfor:its its myown webuniversity}, month = {09}, organization = {Gesellschaft für Informatik e.V. (GI)}, pages = {235-246}, publisher = {Gesellschaft für Informatik e.V. (GI)}, series = {Lecture Notes in Informatics}, title = {Digitale Arbeitsblätter mit interaktiven Programmieraufgaben im Informatik-Unterricht}, volume = {P-308}, year = 2020 }

2019

1.
Serth, S., Teusner, R., Renz, J., Uflacker, M.: Evaluating Digital Worksheets with Interactive Programming Exercises for K-12 Education In: Proceedings of the 2019 IEEE Frontiers in Education Conference (FIE). IEEE (2019)
[ Abstract ] [ BibTeX ] [ URL ] [ DOI ] [ Download ]
 
This Research Full Paper presents insights from digital worksheets with embedded interactive programming exercises tailored for high-school students new to programming. Computer Science teachers often incorporate existing videos, quizzes, and practical programming exercises from Massive Open Online Courses (MOOCs). However, teachers' options to adapt the content to their specific needs are currently limited. Based on a qualitative survey with thirteen teachers, we developed a software prototype which allows teachers to create their own interactive worksheets consisting of texts, videos, quizzes, and practical programming exercises. Additionally, teachers can embed and further customize existing exercises from MOOCs. Further, we enable teachers to gain deeper insights by providing results from automated submission analysis, thus uncovering knowledge gaps and fostering content-driven in-class discussions. Our evaluation shows that the concept was well received by students and teachers alike: Teachers noticed the possibility of a shift in their role from a lecturing instructor to an individual tutor, as students are enabled to learn at their own pace and receive specific, direct feedback based on automated unit tests. Interactive worksheets, as an integrated part of digital education, thus foster informed teacher interventions as part of an individualized student learning process.
@inproceedings{serthEvaluatingDigitalWorksheets2019, abstract = {This Research Full Paper presents insights from digital worksheets with embedded interactive programming exercises tailored for high-school students new to programming. Computer Science teachers often incorporate existing videos, quizzes, and practical programming exercises from Massive Open Online Courses (MOOCs). However, teachers' options to adapt the content to their specific needs are currently limited. Based on a qualitative survey with thirteen teachers, we developed a software prototype which allows teachers to create their own interactive worksheets consisting of texts, videos, quizzes, and practical programming exercises. Additionally, teachers can embed and further customize existing exercises from MOOCs. Further, we enable teachers to gain deeper insights by providing results from automated submission analysis, thus uncovering knowledge gaps and fostering content-driven in-class discussions. Our evaluation shows that the concept was well received by students and teachers alike: Teachers noticed the possibility of a shift in their role from a lecturing instructor to an individual tutor, as students are enabled to learn at their own pace and receive specific, direct feedback based on automated unit tests. Interactive worksheets, as an integrated part of digital education, thus foster informed teacher interventions as part of an individualized student learning process.}, author = {Serth, Sebastian and Teusner, Ralf and Renz, Jan and Uflacker, Matthias}, booktitle = {Proceedings of the 2019 IEEE Frontiers in Education Conference (FIE)}, keywords = {epic its myown webUniversity}, month = 10, organization = {IEEE Education Society}, publisher = {IEEE}, series = {FIE 2019}, title = {Evaluating Digital Worksheets with Interactive Programming Exercises for K-12 Education}, year = 2019 }

2.
Serth, S.: Integrating Professional Tools in Programming Education with MOOCs In: Proceedings of the 2019 IEEE Frontiers in Education Conference (FIE). IEEE (2019)
[ Abstract ] [ BibTeX ] [ URL ] [ DOI ] [ Download ]
 
An increasing number of high school teachers use existing Massive Open Online Courses (MOOCs) concerning programming education. Most MOOCs focus on teaching the basics of a programming language and common concepts or patterns. MOOC platforms usually provide their own code execution environments and thus have full control over the features and appearance available to learners. However, only a subset of tools available to professional software engineers is used in introductory programming MOOCs. While the reduction of features is helpful to ease navigation for novices, we assume that learners benefit from more advanced features at a later stage in the learning process. To help students minimize bugs and conceptual mistakes, we intend to evaluate how pair programming could be enabled for remote peers in MOOCs with a synchronized editor and an additional communication channel. Further, we plan to use static program analysis to get more insights about the code written by learners and to provide early feedback about the coding style. One of our contributions will be to identify possibilities to integrate professional tools and methods in MOOCs supported by an evaluation from learners.
@inproceedings{serthIntegratingProfessionalTools2019, abstract = {An increasing number of high school teachers use existing Massive Open Online Courses (MOOCs) concerning programming education. Most MOOCs focus on teaching the basics of a programming language and common concepts or patterns. MOOC platforms usually provide their own code execution environments and thus have full control over the features and appearance available to learners. However, only a subset of tools available to professional software engineers is used in introductory programming MOOCs. While the reduction of features is helpful to ease navigation for novices, we assume that learners benefit from more advanced features at a later stage in the learning process. To help students minimize bugs and conceptual mistakes, we intend to evaluate how pair programming could be enabled for remote peers in MOOCs with a synchronized editor and an additional communication channel. Further, we plan to use static program analysis to get more insights about the code written by learners and to provide early feedback about the coding style. One of our contributions will be to identify possibilities to integrate professional tools and methods in MOOCs supported by an evaluation from learners.}, author = {Serth, Sebastian}, booktitle = {Proceedings of the 2019 IEEE Frontiers in Education Conference (FIE)}, keywords = {its myown webuniversity}, month = 10, organization = {IEEE Education Society}, publisher = {IEEE}, title = {Integrating Professional Tools in Programming Education with MOOCs}, year = 2019 }

3.
Serth, S.: Individual Worksheets with Interactive Programming Exercises within the HPI Schul-Cloud In: Master’s Thesis. Hasso Plattner Institute, University of Potsdam (2019)
Best Master Theses in Technology-enhanced Learning 2019 (awarded by the educational technology special interest group of the German informatics society)
[ Abstract ] [ BibTeX ] [ Download ]
 
Modern computer science education in high-schools requires students to learn the basics of programming. In terms of content, teachers often incorporate existing videos, quizzes, and practical programming exercises from Massive Open Online Courses (MOOCs). However, teachers' options to adapt the content to their specific needs or to add their own material are currently limited. Based on a qualitative survey with thirteen teachers, we developed tools to extend these options. Our software prototype allows teachers to create their own interactive worksheets consisting of texts, videos, quizzes, and practical programming exercises. Additionally, teachers can embed and further customize existing exercises from MOOCs. Further, we enable teachers to gain deeper insights into the learning progress of their students by providing results from automated submission analysis. These data allow uncovering potential knowledge gaps and foster content-driven in-class discussions. In this thesis, we present findings from an evaluation with different school classes using our software. The concept was well received by students and teachers alike: Teachers noticed the possibility of a shift in their role from a lecturing instructor to an individual tutor, as students are enabled to learn at their own pace and receive specific, direct feedback based on automated unit tests. For the preparation of upcoming lessons, teachers valued the ability to analyze common mistakes of their students to uncover and discuss previously hidden problems. Interactive worksheets, as an integrated part of digital education, thus foster informed teacher interventions as part of an individualized student learning process.
@inproceedings{serthIndividualWorksheetsInteractive2019, abstract = {Modern computer science education in high-schools requires students to learn the basics of programming. In terms of content, teachers often incorporate existing videos, quizzes, and practical programming exercises from Massive Open Online Courses (MOOCs). However, teachers' options to adapt the content to their specific needs or to add their own material are currently limited. Based on a qualitative survey with thirteen teachers, we developed tools to extend these options. Our software prototype allows teachers to create their own interactive worksheets consisting of texts, videos, quizzes, and practical programming exercises. Additionally, teachers can embed and further customize existing exercises from MOOCs. Further, we enable teachers to gain deeper insights into the learning progress of their students by providing results from automated submission analysis. These data allow uncovering potential knowledge gaps and foster content-driven in-class discussions. In this thesis, we present findings from an evaluation with different school classes using our software. The concept was well received by students and teachers alike: Teachers noticed the possibility of a shift in their role from a lecturing instructor to an individual tutor, as students are enabled to learn at their own pace and receive specific, direct feedback based on automated unit tests. For the preparation of upcoming lessons, teachers valued the ability to analyze common mistakes of their students to uncover and discuss previously hidden problems. Interactive worksheets, as an integrated part of digital education, thus foster informed teacher interventions as part of an individualized student learning process.}, author = {Serth, Sebastian}, booktitle = {Master's Thesis}, institution = {Hasso Plattner Institute, University of Potsdam}, keywords = {sys:relevantfor:its epic its myown webuniversity}, month = {05}, note = {Best Master Theses in Technology-enhanced Learning 2019 (awarded by the educational technology special interest group of the German informatics society)}, publisher = {Hasso Plattner Institute, University of Potsdam}, school = {Hasso Plattner Institute, University of Potsdam}, title = {Individual Worksheets with Interactive Programming Exercises within the HPI Schul-Cloud}, year = 2019 }

2018

1.
Cabral, F., Shah, S., Zhou, Z., Serth, S., Krogmann, S., Lötzsch, W.: VAMO – What Story Do You Want to Tell? Stanford University (2018)
[ Abstract ] [ BibTeX ] [ URL ] [ Download ]
 
As technology improves it becomes more and more present in our everyday lives. Artificial Intel- ligence (AI) is a field of research that has existed for the past sixty years but only recently has it become ubiquitous. In the current context we live in, AI is present in smartphones and many ap- plications we use daily from search engines to image processing to recommendation engines. AI is finishing our sentences and learning our taste. Our team, comprised of three graduate students from Stanford University and three from Hasso Plattner Institute (HPI), Potsdam, has been approached by FutureWei Technologies to enhance human communication with Artificial Intelligence.
@techreport{noauthororeditor, abstract = {As technology improves it becomes more and more present in our everyday lives. Artificial Intel- ligence (AI) is a field of research that has existed for the past sixty years but only recently has it become ubiquitous. In the current context we live in, AI is present in smartphones and many ap- plications we use daily from search engines to image processing to recommendation engines. AI is finishing our sentences and learning our taste. Our team, comprised of three graduate students from Stanford University and three from Hasso Plattner Institute (HPI), Potsdam, has been approached by FutureWei Technologies to enhance human communication with Artificial Intelligence.}, author = {Cabral, Felipe and Shah, Simran and Zhou, Zhiheng and Serth, Sebastian and Krogmann, Simon and Lötzsch, Winfried}, booktitle = {Stanford ME310 Project Based Engineering Design Reports}, institution = {Stanford University & Hasso Plattner Institute}, keywords = {epic myown}, month = {06}, publisher = {Stanford University}, series = {Stanford ME310 Project Based Engineering Design Reports}, title = {VAMO – What Story Do You Want to Tell?}, type = {Publication}, year = 2018 }

2017

1.
Serth, S., Podlesny, N., Bornstein, M., Lindemann, J., Latt, J., Selke, J., Schlosser, R., Boissier, M., Uflacker, M.: An Interactive Platform to Simulate Dynamic Pricing Competition on Online Marketplaces In: 21st IEEE International Enterprise Distributed Object Computing Conference, EDOC 2017, Quebec City, QC, Canada, October 10-13, 2017. pp. 61–66. IEEE (2017)
[ Abstract ] [ BibTeX ] [ URL ] [ DOI ] [ Download ]
 
E-commerce marketplaces are highly dynamic with constant competition. While this competition is challenging for many merchants, it also provides plenty of opportunities, e.g., by allowing them to automatically adjust prices in order to react to changing market situations. For practitioners however, testing automated pricing strategies is time-consuming and potentially hazardously when done in production. Researchers, on the other side, struggle to study how pricing strategies interact under heavy competition. As a consequence, we built an open continuous time framework to simulate dynamic pricing competition called Price Wars. The microservice-based architecture provides a scalable platform for large competitions with dozens of merchants and a large random stream of consumers. Our platform stores each event in a distributed log. This allows to provide different performance measures enabling users to compare profit and revenue of various repricing strategies in real-time. For researchers, price trajectories are shown which ease evaluating mutual price reactions of competing strategies. Furthermore, merchants can access historical marketplace data and apply machine learning. By providing a set of customizable, artificial merchants, users can easily simulate both simple rule-based strategies as well as sophisticated data-driven strategies using demand learning to optimize their pricing strategies.
@inproceedings{serthInteractivePlatformSimulate2017, abstract = {E-commerce marketplaces are highly dynamic with constant competition. While this competition is challenging for many merchants, it also provides plenty of opportunities, e.g., by allowing them to automatically adjust prices in order to react to changing market situations. For practitioners however, testing automated pricing strategies is time-consuming and potentially hazardously when done in production. Researchers, on the other side, struggle to study how pricing strategies interact under heavy competition. As a consequence, we built an open continuous time framework to simulate dynamic pricing competition called Price Wars. The microservice-based architecture provides a scalable platform for large competitions with dozens of merchants and a large random stream of consumers. Our platform stores each event in a distributed log. This allows to provide different performance measures enabling users to compare profit and revenue of various repricing strategies in real-time. For researchers, price trajectories are shown which ease evaluating mutual price reactions of competing strategies. Furthermore, merchants can access historical marketplace data and apply machine learning. By providing a set of customizable, artificial merchants, users can easily simulate both simple rule-based strategies as well as sophisticated data-driven strategies using demand learning to optimize their pricing strategies.}, author = {Serth, Sebastian and Podlesny, Nikolai and Bornstein, Marvin and Lindemann, Jan and Latt, Johanna and Selke, Jan and Schlosser, Rainer and Boissier, Martin and Uflacker, Matthias}, booktitle = {21st IEEE International Enterprise Distributed Object Computing Conference, EDOC 2017, Quebec City, QC, Canada, October 10-13, 2017}, keywords = {epic its myown}, month = 10, organization = {IEEE Computer Society}, pages = {61-66}, publisher = {IEEE}, title = {An Interactive Platform to Simulate Dynamic Pricing Competition on Online Marketplaces}, year = 2017 }

2.
Boissier, M., Schlosser, R., Podlesny, N., Serth, S., Bornstein, M., Latt, J., Lindemann, J., Selke, J., Uflacker, M.: Data-Driven Repricing Strategies in Competitive Markets: An Interactive Simulation Platform In: Proceedings of the Eleventh ACM Conference on Recommender Systems (RecSys ’17). pp. 355–357. ACM, New York, NY, USA (2017)
[ Abstract ] [ BibTeX ] [ URL ] [ DOI ] [ Download ]
 
Modern e-commerce platforms pose both opportunities as well as hurdles for merchants. While merchants can observe markets at any point in time and automatically reprice their products, they also have to compete simultaneously with dozens of competitors. Currently, retailers lack the possibility to test, develop, and evaluate their algorithms appropriately before releasing them into the real world. At the same time, it is challenging for researchers to investigate how pricing strategies interact with each other under heavy competition. To study dynamic pricing competition on online marketplaces, we built an open simulation platform. To be both flexible and scalable, the platform has a microservice-based architecture and handles large numbers of competing merchants and arriving consumers. It allows merchants to deploy the full width of pricing strategies, from simple rule-based strategies to more sophisticated data-driven strategies using machine learning. Our platform enables analyses of how a strategy’s performance is affected by customer behavior, price adjustment frequencies, the competitors’ strategies, and the exit/entry of competitors. Moreover, our platform allows to study the long-term behavior of self-adapting strategies.
@inproceedings{boissierDataDrivenRepricingStrategies2017a, abstract = {Modern e-commerce platforms pose both opportunities as well as hurdles for merchants. While merchants can observe markets at any point in time and automatically reprice their products, they also have to compete simultaneously with dozens of competitors. Currently, retailers lack the possibility to test, develop, and evaluate their algorithms appropriately before releasing them into the real world. At the same time, it is challenging for researchers to investigate how pricing strategies interact with each other under heavy competition. To study dynamic pricing competition on online marketplaces, we built an open simulation platform. To be both flexible and scalable, the platform has a microservice-based architecture and handles large numbers of competing merchants and arriving consumers. It allows merchants to deploy the full width of pricing strategies, from simple rule-based strategies to more sophisticated data-driven strategies using machine learning. Our platform enables analyses of how a strategy’s performance is affected by customer behavior, price adjustment frequencies, the competitors’ strategies, and the exit/entry of competitors. Moreover, our platform allows to study the long-term behavior of self-adapting strategies.}, address = {New York, NY, USA}, author = {Boissier, Martin and Schlosser, Rainer and Podlesny, Nikolai and Serth, Sebastian and Bornstein, Marvin and Latt, Johanna and Lindemann, Jan and Selke, Jan and Uflacker, Matthias}, booktitle = {Proceedings of the Eleventh ACM Conference on Recommender Systems (RecSys '17)}, keywords = {epic its myown}, month = {08}, organization = {ACM Press}, pages = {355-357}, publisher = {ACM}, series = {RecSys '17}, title = {Data-Driven Repricing Strategies in Competitive Markets: An Interactive Simulation Platform}, year = 2017 }

3.
Serth, S., Haarmann, S., Faber, L.: Serving Live Multimedia for the Linked Open Data Cloud In: Eibl, M. and Gaedke, M. (eds.) GI-Edition-Lecture Notes in Informatics 275: Informatik 2017, 47. Jahrestagung der Gesellschaft für Informatik e.V. (GI). pp. 2487–2498. Gesellschaft für Informatik e.V. (GI), Bonn, Germany (2017)
[ Abstract ] [ BibTeX ] [ URL ] [ DOI ] [ Download ]
 
DBpedia is a community-driven project to extract semantic data fromWikipedia articles. It publishes the results as RDF data in the Linked Open Data Cloud.With DBpedia Live, the community enabled live updates of linked data using the OAI-PMH protocol to receive and process changes on Wikipedia. The MediaWiki foundation discontinued their support for OAI-PMH in March 2016 causing DBpedia Live to no longer receive live updates. In this work, we use RCStream, the new MediaWiki protocol to notify other systems of changes, to re-enable live updates in DBpedia Live. Currently, users need to consume two DBpedia resources to access general information and multimedia files about one entity. On the one hand DBpedia holds the structured information. On the other DBpedia Commons holds most multimedia information. We improve the integration of multimedia data into DBpedia by introducing a new extractor to the DBpedia Extraction Framework that extracts most multimedia data from a Wikipedia page. Additionally, we present two further extractors that link pages in DBpedia with pages in DBpedia Commons and vice versa. All our changes are available in the DBpedia Extraction Framework and in use, e.g. for DBpedia Live.
@inproceedings{serthServingLiveMultimedia2017, abstract = {DBpedia is a community-driven project to extract semantic data fromWikipedia articles. It publishes the results as RDF data in the Linked Open Data Cloud.With DBpedia Live, the community enabled live updates of linked data using the OAI-PMH protocol to receive and process changes on Wikipedia. The MediaWiki foundation discontinued their support for OAI-PMH in March 2016 causing DBpedia Live to no longer receive live updates. In this work, we use RCStream, the new MediaWiki protocol to notify other systems of changes, to re-enable live updates in DBpedia Live. Currently, users need to consume two DBpedia resources to access general information and multimedia files about one entity. On the one hand DBpedia holds the structured information. On the other DBpedia Commons holds most multimedia information. We improve the integration of multimedia data into DBpedia by introducing a new extractor to the DBpedia Extraction Framework that extracts most multimedia data from a Wikipedia page. Additionally, we present two further extractors that link pages in DBpedia with pages in DBpedia Commons and vice versa. All our changes are available in the DBpedia Extraction Framework and in use, e.g. for DBpedia Live.}, address = {Bonn, Germany}, author = {Serth, Sebastian and Haarmann, Stephan and Faber, Lukas}, booktitle = {GI-Edition-Lecture Notes in Informatics 275: Informatik 2017, 47. Jahrestagung der Gesellschaft für Informatik e.V. (GI)}, editor = {Eibl, Maximilian and Gaedke, Martin}, keywords = {FutureInternet its myown}, month = {07}, organization = {Gesellschaft für Informatik e.V. (GI)}, pages = {2487-2498}, publisher = {Gesellschaft für Informatik e.V. (GI)}, series = {Lecture Notes in Informatics}, title = {Serving Live Multimedia for the Linked Open Data Cloud}, volume = {P-275}, year = 2017 }

4.
Seitz, K., Serth, S., Krentz, K.-F., Meinel, C.: Demo: Enabling En-Route Filtering for End-to-End Encrypted CoAP Messages In: Proceedings of the 15th ACM Conference on Embedded Networked Sensor Systems (SenSys 2017). ACM Press, New York, NY, USA (2017)
[ Abstract ] [ BibTeX ] [ URL ] [ DOI ] [ Download ]
 
IoT devices usually are battery-powered and directly connected to the Internet. This makes them vulnerable to so-called path-based denial-of-service (PDoS) attacks. For example, in a PDoS attack an adversary sends multiple Constrained Application Protocol (CoAP) messages towards an IoT device, thereby causing each IoT device along the path to expend energy for forwarding this message. Current end-to-end security solutions, such as DTLS or IPsec, fail to prevent such attacks since they only filter out inauthentic CoAP messages at their destination. This demonstration shows an approach to allow en-route filtering where a trusted gateway has all necessary information to check the integrity, decrypt and, if necessary, drop a message before forwarding it to the constrained mote. Our approach preserves precious resources of IoT devices in the face of path-based denial-of-service attacks by remote attackers.
@inproceedings{seitzEnablingEnRouteFiltering2017, abstract = {IoT devices usually are battery-powered and directly connected to the Internet. This makes them vulnerable to so-called path-based denial-of-service (PDoS) attacks. For example, in a PDoS attack an adversary sends multiple Constrained Application Protocol (CoAP) messages towards an IoT device, thereby causing each IoT device along the path to expend energy for forwarding this message. Current end-to-end security solutions, such as DTLS or IPsec, fail to prevent such attacks since they only filter out inauthentic CoAP messages at their destination. This demonstration shows an approach to allow en-route filtering where a trusted gateway has all necessary information to check the integrity, decrypt and, if necessary, drop a message before forwarding it to the constrained mote. Our approach preserves precious resources of IoT devices in the face of path-based denial-of-service attacks by remote attackers.}, address = {New York, NY, USA}, author = {Seitz, Klara and Serth, Sebastian and Krentz, Konrad-Felix and Meinel, Christoph}, booktitle = {Proceedings of the 15th ACM Conference on Embedded Networked Sensor Systems (SenSys 2017)}, keywords = {IoT its myown}, month = {02}, organization = {ACM Press}, publisher = {ACM Press}, series = {SenSys '17}, title = {Demo: Enabling En-Route Filtering for End-to-End Encrypted CoAP Messages}, year = 2017 }