About

Dr. Bradley M. Hemminger is an Associate Professor at the UNC School of Information and Library Science (SILS) with a joint appointment in the Center for Ethical, Legal, and Social Implications of Biotechnology. His research interests include digital scholarship, information seeking, information visualization, user interface design, augmented and virtual reality, digital libraries, and biomedical health informatics. He has published over 85 papers, served on several international standards committees, and consulted for various companies in visualization and user interfaces. Dr. Hemminger currently teaches courses such as scholarly communications, databases, biomedical health informatics, information visualization, and data science. He is the director of the Informatics and Visualization Lab at UNC, part of the Interactive Information Systems Lab, and also directs the Center for Research and Development of Digital Libraries. His current research focuses on developing new paradigms for scholarship, publishing, and information seeking and use by academics in the digital age.

Research topics

• Computer Science
• Sociology
• Computer Security
• Medicine
• Internet privacy

Selected publications

• Measuring Toxicity Toward Women in Game-Based Communities

  UNC Libraries · 2025-03-29

  articleOpen access1st authorCorresponding

  Prior research into gaming toxicity in game-specific Reddit communities nearly always considers toxicity in aggregate, and so provides very few clues for a valid coding scheme for isolating toxic language and triggers that specifically target women gamers. Existing research offers a starting place for devising valid methods for measuring and detecting toxic language and toxic triggers within specified data sets, but that research is less useful is its applicability to game-related forms of toxicity targeting women gamers. Where this research had originally hoped to develop an automated method for scoring, limitations with automated detection of toxicity discussed within the paper prompted a shift to what the authors identify as a key intermediate step—better accuracy in toxicity detection by automated means—that will contribute to future achievements in reducing toxicity toward women and other targeted groups in gaming communities. This paper is intended to aid projects that aim to incrementally improve our understanding of toxicity toward women in games and game communities and how to effectively measure it. The conclusion of this research ultimately hopes to contribute to providing information to inform policies that create a safer and more respectful gaming environment for all gamers.

  PublisherDOI

• Measuring Toxicity Toward Women in Game-Based Communities

  Journal of Electronic Gaming and Esports · 2023 · 6 citations

  Senior authorCorresponding
  • Computer Science
  • Computer Science
  • Computer Security

  Prior research into gaming toxicity in game-specific Reddit communities nearly always considers toxicity in aggregate, and so provides very few clues for a valid coding scheme for isolating toxic language and triggers that specifically target women gamers. Existing research offers a starting place for devising valid methods for measuring and detecting toxic language and toxic triggers within specified data sets, but that research is less useful is its applicability to game-related forms of toxicity targeting women gamers. Where this research had originally hoped to develop an automated method for scoring, limitations with automated detection of toxicity discussed within the paper prompted a shift to what the authors identify as a key intermediate step—better accuracy in toxicity detection by automated means—that will contribute to future achievements in reducing toxicity toward women and other targeted groups in gaming communities. This paper is intended to aid projects that aim to incrementally improve our understanding of toxicity toward women in games and game communities and how to effectively measure it. The conclusion of this research ultimately hopes to contribute to providing information to inform policies that create a safer and more respectful gaming environment for all gamers.

  PublisherOA PDFDOI

• A curricula-based comparison of biomedical and health informatics programs in the USA

  UNC Libraries · 2020-11-05 · 5 citations

  articleOpen accessSenior author

  The field of Biomedical and Health Informatics (BMHI) continues to define itself, and there are many educational programs offering ‘informatics’ degrees with varied foci. The goal of this study was to develop a scheme for systematic comparison of programs across the entire BMHI spectrum and to identify commonalities among informatics curricula.

  PublisherDOI

• Contrast Limited Adaptive Histogram Equalization image processing to improve the detection of simulated spiculations in dense mammograms

  UNC Libraries · 2020-11-04

  articleOpen access

  The purpose of this project was to determine whether Contrast Limited Adaptive Histogram Equalization (CLAHE) improves detection of simulated spiculations in dense mammograms. Lines simulating the appearance of spiculations, a common marker of malignancy when visualized with masses, were embedded in dense mammograms digitized at 50 micron pixels, 12 bits deep. Film images with no CLAHE applied were compared to film images with nine different combinations of clip levels and region sizes applied. A simulated spiculation was embedded in a background of dense breast tissue, with the orientation of the spiculation varied. The key variables involved in each trial included the orientation of the spiculation, contrast level of the spiculation and the CLAHE settings applied to the image. Combining the 10 CLAHE conditions, 4 contrast levels and 4 orientations gave 160 combinations. The trials were constructed by pairing 160 combinations of key variables with 40 backgrounds. Twenty student observers were asked to detect the orientation of the spiculation in the image. There was a statistically significant improvement in detection performance for spiculations with CLAHE over unenhanced images when the region size was set at 32 with a clip level of 2, and when the region size was set at 32 with a clip level of 4. The selected CLAHE settings should be tested in the clinic with digital mammograms to determine whether detection of spiculations associated with masses detected at mammography can be improved.

  PublisherDOI

• Does intensity windowing improve the detection of simulated calcifications in dense mammograms?

  UNC Libraries · 2020-11-04

  articleOpen access

  This study attempts to determine whether intensity windowing (IW) improves detection of simulated calcifications in dense mammograms. Clusters of five simulated calcifications were embedded in dense mammograms digitized at 50-microns pixels, 12 bits deep. Film images with no windowing applied were compared with film images with nine different window widths and levels applied. A simulated cluster was embedded in a realistic background of dense breast tissue, with the position of the cluster varied. The key variables involved in each trial included the position of the cluster, contrast level of the cluster, and the IW settings applied to the image. Combining the ten IW conditions, four contrast levels and four quadrant positions gave 160 combinations. The trials were constructed by pairing 160 combinations of key variables with 160 backgrounds. The entire experiment consisted of 800 trials. Twenty student observers were asked to detect the quadrant of the image in which the mass was located. There was a statistically significant improvement in detection performance for clusters of calcifications when the window width was set at 1024 with a level of 3328, and when the window width was set at 1024 with a level of 3456. The selected IW settings should be tested in the clinic with digital mammograms to determine whether calcification detection performance can be improved.

  PublisherDOI

• Decoupling the scholarly journal

  UNC Libraries · 2020-11-02

  articleOpen access1st authorCorresponding

  Although many observers have advocated the reform of the scholarly publishing system, improvements to functions like peer review have been adopted sluggishly. We argue that this is due to the tight coupling of the journal system: the system's essential functions of archiving, registration, dissemination, and certification are bundled together and siloed into tens of thousands of individual journals. This tight coupling makes it difficult to change any one aspect of the system, choking out innovation. We suggest that the solution is the “decoupled journal (DcJ).” In this system, the functions are unbundled and performed as services, able to compete for patronage and evolve in response to the market. For instance, a scholar might deposit an article in her institutional repository, have it copyedited and typeset by one company, indexed for search by several others, self-marketed over her own social networks, and peer reviewed by one or more stamping agencies that connect her paper to external reviewers. The DcJ brings publishing out of its current seventeenth-century paradigm, and creates a Web-like environment of loosely joined pieces—a marketplace of tools that, like the Web, evolves quickly in response to new technologies and users' needs. Importantly, this system is able to evolve from the current one, requiring only the continued development of bolt-on services external to the journal, particularly for peer review.

  PublisherDOI

• Soft Copy Display Requirements for Digital Mammography

  UNC Libraries · 2020-11-04

  articleOpen access1st authorCorresponding

  One of the advantages of digital mammography is to display mammograms on softcopy (electronic displays). Softcopy display of mammography is challenging because of the spatial and contrast resolution demands present in mammograms. We have designed and developed a softcopy mammography display application, Mammoview, which is capable of allowing radiologists to read mammograms as quickly and as accurately as they can on film alternators. We review the studies using Mammoview to elucidate the requirements of a successful softcopy display station. The design and development of the Mammoview softcopy display station are described in this article, and results of several studies using Mammoview are reported, including subjective feedback from Radiological Society of North America (RSNA) conference demonstrations, and clinical studies measuring performance in terms of speed and accuracy. Additional analysis of user interactions and user feedback is used to study the successes and shortcomings of mammography display stations like Mammoview. Overall, radiologist readings using Mammoview have been shown to be as fast and as accurate as readings using mammography film alternators. However, certain parts of the softcopy interface were more successful than their film counterparts, whereas others were less successful. Data analysis of the recorded human-computer interactions for the softcopy component of the clinical trial indicate statistically significant correlations between the difference in review time of softcopy versus alternator readings and three factors: the number of interactions, the reader, and the size of the image being reviewed. The first factor (number of interactions) suggests that simpler interfaces require less time to use; the second factor, the reader, supports previous findings that radiologists vary in how fast they read screening mammography studies; the third, size of image, suggests that the speed of softcopy review is increased relative to film readings when images are significantly larger than the display size. Feedback from radiologists using the system in clinical trials and at demonstration exhibits at RSNA indicated good acceptance of the interface and easy adaptation. Radiologists indicated that they felt comfortable using the interface, and that they would use such a softcopy interface in clinical practice. Finally, preliminary work suggests that the addition of a simple interaction to incorporate computer-aided detection (CAD) results would improve reading accuracy without significantly increasing reader times.

  PublisherDOI

• Assessment of Real-Time 3D Visualization for Cardiothoracic Diagnostic Evaluation and Surgery Planning

  UNC Libraries · 2020-11-04 · 1 citations

  articleOpen access

  RATIONALE AND OBJECTIVES: Three-dimensional (3D) real-time volume rendering has demonstrated improvements in clinical care for several areas of radiological imaging. We test whether advanced real-time rendering techniques combined with an effective user interface will allow radiologists and surgeons to improve their performance for cardiothoracic surgery planning and diagnostic evaluation. MATERIAL AND METHODS: An interactive combination 3D and 2D visualization system developed at the University of North Carolina at Chapel Hill was compared against standard tiled 2D slice presentation on a viewbox. The system was evaluated for 23 complex cardiothoracic computed tomographic (CT) cases including heart-lung and lung transplantation, tumor resection, airway stent placement, repair of congenital heart defects, aortic aneurysm repair, and resection of pulmonary arteriovenous malformation. Radiologists and surgeons recorded their impressions with and without the use of the interactive visualization system. RESULTS: The cardiothoracic surgeons reported positive benefits to using the 3D visualizations. The addition of the 3D visualization changed the surgical plan (65% of cases), increased the surgeon's confidence (on average 40% per case), and correlated well with the anatomy found at surgery (95% of cases). The radiologists reported fewer and less major changes than the surgeons in their understanding of the case due to the 3D visualization. They found new findings or additional information about existing findings in 66% of the cases; however, they changed their radiology report in only 14% of the cases. CONCLUSION: With the appropriate choice of 3D real-time volume rendering and a well-designed user interface, both surgeons and radiologists benefit from viewing an interactive 3D visualization in addition to 2D images for surgery planning and diagnostic evaluation of complex cardiothoracic cases. This study finds that 3D visualization is especially helpful to the surgeon in understanding the case, and in communicating and planning the surgery. These results suggest that including real-time 3D visualization would be of clinical benefit for complex cardiothoracic CT cases.

  PublisherDOI

• The effect of intensity windowing on the detection of simulated masses embedded in dense portions of digitized mammograms in a laboratory setting

  UNC Libraries · 2020-11-04

  articleOpen access

  The purpose of this study was to determine whether intensity windowing (IW) improves detection of simulated masses in dense mammograms. Simulated masses were embedded in dense mammograms digitized at 50 microns/pixel, 12 bits deep. Images were printed with no windowing applied and with nine window width and level combinations applied. A simulated mass was embedded in a realistic background of dense breast tissue, with the position of the mass (against the background) varied. The key variables involved in each trial included the position of the mass, the contrast levels and the IW setting applied to the image. Combining the 10 image processing conditions, 4 contrast levels, and 4 quadrant positions gave 160 combinations. The trials were constructed by pairing 160 combinations of key variables with 160 backgrounds. The entire experiment consisted of 800 trials. Twenty observers were asked to detect the quadrant of the image into which the mass was located. There was a statistically significant improvement in detection performance for masses when the window width was set at 1024 with a level of 3328. IW should be tested in the clinic to determine whether mass detection performance in real mammograms is improved.

  PublisherDOI

• Comparison of Navigation Techniques for Large Digital Images

  UNC Libraries · 2020-11-04

  articleOpen access

  Medical images are examined on computer screens in a variety of contexts. Frequently, these images are larger than computer screens, and computer applications support different paradigms for user navigation of large images. The paper reports on a systematic investigation of what interaction techniques are the most effective for navigating images larger than the screen size for the purpose of detecting small image features. An experiment compares five different types of geometrically zoomable interaction techniques, each at two speeds (fast and slow update rates) for the task of finding a known feature in the image. There were statistically significant performance differences between several groupings of the techniques. The fast versions of the ArrowKey, Pointer, and ScrollBar performed the best. In general, techniques that enable both intuitive and systematic searching performed the best at the fast speed, while techniques that minimize the number of interactions with the image were more effective at the slow speed. Additionally, based on a postexperiment questionnaire and qualitative comparison, users expressed a clear preference for the Pointer technique, which allowed them to more freely and naturally interact with the image.

  PublisherDOI

Frequent coauthors

• Keith E. Muller

  University of Florida Health

  27 shared

• Etta D. Pisano

  University of Pennsylvania

  26 shared

• Richard Johnston

  Swansea University

  20 shared

• Stephen M. Pizer

  19 shared

• David V. Beard

  Sheffield Hallam University

  19 shared

• M. Patricia Braeuning

  Christ Hospital

  14 shared

• Shenmeng Xu

  Vanderbilt University

  9 shared

• Martin J. Yaffe

  Ontario Institute for Cancer Research

  7 shared

Labs

• Equity in Making (EITM) LabPI

Awards & honors

• American Society for Information Science and Technology (ASI…
• American College of Radiology (ACR) Distinguished Committee…
• Certificate of Merit for scientific poster in Radiology Soci…
• Honorable Mention: Best Scientific Exhibit, RSNA 2000 confer…
• Invited to present to Swedish Institute for Standards on int…