Volumetric real-time particle-based representation of large unstructured tetrahedral polygon meshes

In this paper we propose a particle-based volume rendering approach for unstructured, three-dimensional, tetrahedral polygon meshes. We stochastically generate millions of particles per second and project them on the screen in real-time. In contrast to previous rendering techniques of tetrahedral volume meshes, our method does not need a prior depth sorting of geometry. Instead, the rendered image is generated by choosing particles closest to the camera. Furthermore, we use spatial superimposing. Each pixel is constructed from multiple subpixels. This approach not only increases projection accuracy, but allows also a combination of subpixels into one superpixel that creates the well-known translucency effect of volume rendering. We show that our method is fast enough for the visualization of unstructured three-dimensional grids with hard real-time constraints and that it scales well for a high number of particles

Effects of improved street lighting on crime

Improved street lighting serves many functions and is used in both public and private settings. The prevention of personal and property crime is one of its objectives in public space, which is the main focus of this review. There are two main theories of why improved street lighting may cause a reduction in crime. The first suggests that improved lighting leads to increased surveillance of potential offenders (both by improving visibility and by increasing the number of people on the street) and hence to increased deterrence of potential offenders. The second suggests that improved lighting signals community investment in the area and that the area is improving, leading to increased community pride, community cohesiveness, and informal social control. The first theory predicts decreases in crime especially during the hours of darkness, while the second theory predicts decreases in crime during both daytime and nighttime. Results of this review indicate that improved street lighting significantly reduces crime. This lends support for the continued use of improved street lighting to prevent crime in public space. The review also found that nighttime crimes did not decrease more than daytime crimes. This suggests that a theory of street lighting focusing on its role in increasing community pride and informal social control may be more plausible than a theory focusing on increased surveillance and increased deterrence. Future research should be designed to test the main theories of the effects of improved street lighting more explicitly, and future lighting schemes should employ high quality evaluation designs with long-term followups

Efficient use of robots in the undergraduate curriculum

In this paper we describe how a single Khepera II robot was used for an assignment in a senior level course on graphical user interface implementation. The assignment required each student to implement a graphical user interface for remotely controlling a Khepera II robot. From the author’s point of view, the focus of the project was how to efficiently and effectively allow the 35 students enrolled in the course to have access to the robot for the purposes of testing and debugging. Furthermore, two of the students were enrolled through the distance education program and were remotely located. The intent was to see if an assignment making use of the robot would stimulate student interest, and whether it could be done with a minimal investment in hardware, lab, and instructor resources. The students were surveyed at the conclusion of the assignment in order to assess the effectiveness of the assignment. The results of this survey are presented, along with plans for future work

Crime stoppers Victoria: an evaluation

Crime stoppers programs generally involve collaboration between police and the media to encourage the public to report information to a toll-free line that may lead to the prevention of a crime or the apprehension of offenders, offering anonymity and the possibility of a reward. Dennis Challinger evaluates the Victorian program in terms of public and media impact, cost, police support, value of information and arrest rates. The study found that the program is useful, valuable and importan

Organic semiconductors, diamond and fingerprint recovery : measuring the energy levels of materials

Optimisation of the energy levels of materials is crucial for the creation of efficient multi-layer electronic devices. This thesis describes measurements of the energy levels of a variety of different types of materials: from cheap, solution processable, organic semiconductors with potential applications from solar cells to OLED displays, to diamond which is expensive but has excellent thermal properties that could make it ideal for high power RF applications. Additionally, common metal surfaces such as brass and iron are studied for small changes in their energy levels at microscopic scales to reveal invisible fingerprints in an energy level map with potential uses within forensic science and policing. These measurements are performed using Kelvin probe and ambient pressure photoemission spectroscopy non-destructive analysis tools. A simple ambient pressure photoemission technique is used to study the ionisation energy of different conjugated polymers. These results were in good agreement with literature results and DFT calculations showing that this method offers a useful alternative to vacuum photoemission analysis or cyclic voltammetry. For the first time, a variety of diamond samples were analysed using combined Kelvin probe and photoemission techniques under ambient conditions. Additionally, hydrogen terminated diamond was investigated under different pressures to study the effect of the presence of a surface water layer on the electron energy level behaviour. A detailed study of fingerprint recovery using the scanning Kelvin probe (SKP) technique across a variety of metal surfaces and donors was conducted. The longevity of the signal was studied with clear identifiable fingermarks revealed from SKP scans after more than three years ageing. As a non-destructive method, SKP analysis of metal surfaces could provide an important first-stage analysis tool for fingerprint recovery or identification of possible touch DNA areas during the investigation of serious and major crime."This work was supported by a Royal Commission for the Exhibition of 1851, ERA Foundation Industrial Fellowship (2016-2019)." -- Fundin