The paper describes a technique to generate high‐quality light field representations from volumetric data. We show how light field galleries can be created to give unexperienced audiences access to ...interactive high‐quality volume renditions. The proposed light field representation is lightweight with respect to storage and bandwidth capacity and is thus ideal as exchange format for visualization results, especially for web galleries.
The approach expands an existing sphere‐hemisphere parameterization for the light field with per‐pixel depth. High‐quality paraboloid maps from volumetric data are generated using GPU‐based ray‐casting or slicing approaches. Different layers, such as isosurfaces, but not restricted to, can be generated independently and composited in real time. This allows the user to interactively explore the model and to change visibility parameters at run‐time.
Image‐based rendering techniques are a powerful alternative to traditional polygon‐based computer graphics. This paper presents a novel light field rendering technique which performs per‐pixel depth ...correction of rays for high‐quality reconstruction. Our technique stores combined RGB and depth values in a parabolic 2D texture for every light field sample acquired at discrete positions on a uniform spherical setup. Image synthesis is implemented on the GPU as a fragment program which extracts the correct image information from adjacent cameras for each fragment by applying per‐pixel depth correction of rays.
We show that the presented image‐based rendering technique provides a significant improvement compared to previous approaches. We explain two different rendering implementations which make use of a uniform parametrisation to minimise disparity problems and ensure full six degrees of freedom for virtual view synthesis. While one rendering algorithm implements an iterative refinement approach for rendering light fields with per pixel depth correction, the other approach employs a raycaster, which provides superior rendering quality at moderate frame rates.
GPU based per‐fragment depth correction of rays, used in both implementations, helps reducing ghosting artifacts to a non‐noticeable amount and provides a rendering technique that performs without exhaustive pre‐processing for 3D object reconstruction and without real‐time ray‐object intersection calculations at rendering time.
In this study, a transcendental phenomenological approach was used to explore faculty members’ experiences with and perceptions of developmental education. This study was conducted at a small, ...open-access university in the Midwest and included the experiences and perspectives of faculty who teach developmental education courses, as well as those who teach non-developmental education courses at this university. Five non-developmental education faculty and four developmental education faculty were interviewed. The interviews were transcribed and a phenomenological reduction approach was used to analyze the data. Results from the analysis process were used to write a textural description of the non-developmental education and developmental education faculty’s experiences with developmental education. Faculty perceptions and experiences were compared to see if both faculty groups had a shared experience with developmental education.
This poster presents preliminary results of our approach to interactively acquire, process and render corresponding depth and light field information. Our system is based on a handheld image based ...range sensor in combination with a commodity digital RGB camera facilitating the synchronous acquisition of registered image data. We demonstrate our intermediate system including the ability to simultaneously acquire and process range and greyscale image data and interactively transforming and rendering the data to geometry.
This research was designed to examine two questions related to the definition of sex-role identity as it is currently represented by the Personal Attributes Questionnaire (PAQ), which was developed ...by Spence, Helmreich, and Stapp in 1974. First, have cultural definitions of masculinity and femininity, as both cultural stereotypes and sex-role related personality characteristics, changed since the development of the PAQ twenty-four years ago? Secondly, do college students and middle-aged, college educated adults of today differ on how they define the stereotypical male and female and on their self-ratings of sex-role sensitive personality traits? These questions were addressed by replicating and expanding the 1973 research procedures with 665 college students, who were similar to the subjects used in 1973, and 92 alumni, who were college students in 1973. Three series of analyses were utilized. First, the initial item scoring and analyses replicating Spence, et. al. (1974) were completed. This provided a categorical classification for each item for each sample group (students 1997 and alumni 1997) by condition (typical, ideal, self), and separately by subject gender group. Secondly, a categorical data modeling procedure was employed to examine the proportion of agreement between the items' categorical classifications by year and subject gender, separately for each of three sample group comparisons (students 1973–students 1997, students 1973–alumni 1997, and students 1997–alumni 1997). Thirdly, a series of multivariate analyses were conducted, comparing the nude and female subjects' mean self-ratings of the 55 items that make up the extended form of the PAQ and comparing the mean self-ratings of the remaining 82 (non-PAQ) items from the original item pool. The findings called into question the construct validity of both the short- and extended-forms of the PAQ, and suggested that new or revised instrumentation be developed. Also, the differences between the 1973 and 1997 students' self-ratings of sex role indicated that instrumentality has increased in female students, and that there has been some decrease in expressiveness in females. Whereas, male students' instrumentality and expressiveness remained consistent between the 1973 and 1997 samples. This research provided an empirical basis as to how societal change might be occurring related to sex-role theory. Lastly, the comparisons of college students to middle-aged alumni indicated that alumni's definitions of sex-role stereotypes and self-ratings of sex-role personality measures differed from the students' ratings. Although this research was not designed to measure developmental differences, this finding suggesting a difference between age groups, was consistent with a developmental perspective.
Currently, the emergence of a novel human coronavirus, SARS-CoV-2, has become a global health concern causing severe respiratory tract infections in humans. Human-to-human transmissions have been ...described with incubation times between 2-10 days, facilitating its spread via droplets, contaminated hands or surfaces. We therefore reviewed the literature on all available information about the persistence of human and veterinary coronaviruses on inanimate surfaces as well as inactivation strategies with biocidal agents used for chemical disinfection, e.g. in healthcare facilities. The analysis of 22 studies reveals that human coronaviruses such as Severe Acute Respiratory Syndrome (SARS) coronavirus, Middle East Respiratory Syndrome (MERS) coronavirus or endemic human coronaviruses (HCoV) can persist on inanimate surfaces like metal, glass or plastic for up to 9 days, but can be efficiently inactivated by surface disinfection procedures with 62–71% ethanol, 0.5% hydrogen peroxide or 0.1% sodium hypochlorite within 1 minute. Other biocidal agents such as 0.05–0.2% benzalkonium chloride or 0.02% chlorhexidine digluconate are less effective. As no specific therapies are available for SARS-CoV-2, early containment and prevention of further spread will be crucial to stop the ongoing outbreak and to control this novel infectious thread.
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